Mercurial > hg > CbC > CbC_gcc
diff gcc/function.c @ 0:a06113de4d67
first commit
author | kent <kent@cr.ie.u-ryukyu.ac.jp> |
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date | Fri, 17 Jul 2009 14:47:48 +0900 |
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children | caeb520cebed 58ad6c70ea60 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/gcc/function.c Fri Jul 17 14:47:48 2009 +0900 @@ -0,0 +1,5645 @@ +/* Expands front end tree to back end RTL for GCC. + Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997, + 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 + Free Software Foundation, Inc. + +This file is part of GCC. + +GCC is free software; you can redistribute it and/or modify it under +the terms of the GNU General Public License as published by the Free +Software Foundation; either version 3, or (at your option) any later +version. + +GCC is distributed in the hope that it will be useful, but WITHOUT ANY +WARRANTY; without even the implied warranty of MERCHANTABILITY or +FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License +for more details. + +You should have received a copy of the GNU General Public License +along with GCC; see the file COPYING3. If not see +<http://www.gnu.org/licenses/>. */ + +/* This file handles the generation of rtl code from tree structure + at the level of the function as a whole. + It creates the rtl expressions for parameters and auto variables + and has full responsibility for allocating stack slots. + + `expand_function_start' is called at the beginning of a function, + before the function body is parsed, and `expand_function_end' is + called after parsing the body. + + Call `assign_stack_local' to allocate a stack slot for a local variable. + This is usually done during the RTL generation for the function body, + but it can also be done in the reload pass when a pseudo-register does + not get a hard register. */ + +#include "config.h" +#include "system.h" +#include "coretypes.h" +#include "tm.h" +#include "rtl.h" +#include "tree.h" +#include "flags.h" +#include "except.h" +#include "function.h" +#include "expr.h" +#include "optabs.h" +#include "libfuncs.h" +#include "regs.h" +#include "hard-reg-set.h" +#include "insn-config.h" +#include "recog.h" +#include "output.h" +#include "basic-block.h" +#include "toplev.h" +#include "hashtab.h" +#include "ggc.h" +#include "tm_p.h" +#include "integrate.h" +#include "langhooks.h" +#include "target.h" +#include "cfglayout.h" +#include "gimple.h" +#include "tree-pass.h" +#include "predict.h" +#include "df.h" +#include "timevar.h" +#include "vecprim.h" + +/* So we can assign to cfun in this file. */ +#undef cfun + +#ifndef STACK_ALIGNMENT_NEEDED +#define STACK_ALIGNMENT_NEEDED 1 +#endif + +#define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT) + +/* Some systems use __main in a way incompatible with its use in gcc, in these + cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to + give the same symbol without quotes for an alternative entry point. You + must define both, or neither. */ +#ifndef NAME__MAIN +#define NAME__MAIN "__main" +#endif + +/* Round a value to the lowest integer less than it that is a multiple of + the required alignment. Avoid using division in case the value is + negative. Assume the alignment is a power of two. */ +#define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1)) + +/* Similar, but round to the next highest integer that meets the + alignment. */ +#define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1)) + +/* Nonzero if function being compiled doesn't contain any calls + (ignoring the prologue and epilogue). This is set prior to + local register allocation and is valid for the remaining + compiler passes. */ +int current_function_is_leaf; + +/* Nonzero if function being compiled doesn't modify the stack pointer + (ignoring the prologue and epilogue). This is only valid after + pass_stack_ptr_mod has run. */ +int current_function_sp_is_unchanging; + +/* Nonzero if the function being compiled is a leaf function which only + uses leaf registers. This is valid after reload (specifically after + sched2) and is useful only if the port defines LEAF_REGISTERS. */ +int current_function_uses_only_leaf_regs; + +/* Nonzero once virtual register instantiation has been done. + assign_stack_local uses frame_pointer_rtx when this is nonzero. + calls.c:emit_library_call_value_1 uses it to set up + post-instantiation libcalls. */ +int virtuals_instantiated; + +/* Assign unique numbers to labels generated for profiling, debugging, etc. */ +static GTY(()) int funcdef_no; + +/* These variables hold pointers to functions to create and destroy + target specific, per-function data structures. */ +struct machine_function * (*init_machine_status) (void); + +/* The currently compiled function. */ +struct function *cfun = 0; + +/* These arrays record the INSN_UIDs of the prologue and epilogue insns. */ +static VEC(int,heap) *prologue; +static VEC(int,heap) *epilogue; + +/* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue + in this function. */ +static VEC(int,heap) *sibcall_epilogue; + +/* Forward declarations. */ + +static struct temp_slot *find_temp_slot_from_address (rtx); +static void pad_to_arg_alignment (struct args_size *, int, struct args_size *); +static void pad_below (struct args_size *, enum machine_mode, tree); +static void reorder_blocks_1 (rtx, tree, VEC(tree,heap) **); +static int all_blocks (tree, tree *); +static tree *get_block_vector (tree, int *); +extern tree debug_find_var_in_block_tree (tree, tree); +/* We always define `record_insns' even if it's not used so that we + can always export `prologue_epilogue_contains'. */ +static void record_insns (rtx, VEC(int,heap) **) ATTRIBUTE_UNUSED; +static int contains (const_rtx, VEC(int,heap) **); +#ifdef HAVE_return +static void emit_return_into_block (basic_block); +#endif +static void prepare_function_start (void); +static void do_clobber_return_reg (rtx, void *); +static void do_use_return_reg (rtx, void *); +static void set_insn_locators (rtx, int) ATTRIBUTE_UNUSED; + +/* Stack of nested functions. */ +/* Keep track of the cfun stack. */ + +typedef struct function *function_p; + +DEF_VEC_P(function_p); +DEF_VEC_ALLOC_P(function_p,heap); +static VEC(function_p,heap) *function_context_stack; + +/* Save the current context for compilation of a nested function. + This is called from language-specific code. */ + +void +push_function_context (void) +{ + if (cfun == 0) + allocate_struct_function (NULL, false); + + VEC_safe_push (function_p, heap, function_context_stack, cfun); + set_cfun (NULL); +} + +/* Restore the last saved context, at the end of a nested function. + This function is called from language-specific code. */ + +void +pop_function_context (void) +{ + struct function *p = VEC_pop (function_p, function_context_stack); + set_cfun (p); + current_function_decl = p->decl; + + /* Reset variables that have known state during rtx generation. */ + virtuals_instantiated = 0; + generating_concat_p = 1; +} + +/* Clear out all parts of the state in F that can safely be discarded + after the function has been parsed, but not compiled, to let + garbage collection reclaim the memory. */ + +void +free_after_parsing (struct function *f) +{ + f->language = 0; +} + +/* Clear out all parts of the state in F that can safely be discarded + after the function has been compiled, to let garbage collection + reclaim the memory. */ + +void +free_after_compilation (struct function *f) +{ + VEC_free (int, heap, prologue); + VEC_free (int, heap, epilogue); + VEC_free (int, heap, sibcall_epilogue); + if (crtl->emit.regno_pointer_align) + free (crtl->emit.regno_pointer_align); + + memset (crtl, 0, sizeof (struct rtl_data)); + f->eh = NULL; + f->machine = NULL; + f->cfg = NULL; + + regno_reg_rtx = NULL; + insn_locators_free (); +} + +/* Return size needed for stack frame based on slots so far allocated. + This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY; + the caller may have to do that. */ + +HOST_WIDE_INT +get_frame_size (void) +{ + if (FRAME_GROWS_DOWNWARD) + return -frame_offset; + else + return frame_offset; +} + +/* Issue an error message and return TRUE if frame OFFSET overflows in + the signed target pointer arithmetics for function FUNC. Otherwise + return FALSE. */ + +bool +frame_offset_overflow (HOST_WIDE_INT offset, tree func) +{ + unsigned HOST_WIDE_INT size = FRAME_GROWS_DOWNWARD ? -offset : offset; + + if (size > ((unsigned HOST_WIDE_INT) 1 << (GET_MODE_BITSIZE (Pmode) - 1)) + /* Leave room for the fixed part of the frame. */ + - 64 * UNITS_PER_WORD) + { + error ("%Jtotal size of local objects too large", func); + return TRUE; + } + + return FALSE; +} + +/* Return stack slot alignment in bits for TYPE and MODE. */ + +static unsigned int +get_stack_local_alignment (tree type, enum machine_mode mode) +{ + unsigned int alignment; + + if (mode == BLKmode) + alignment = BIGGEST_ALIGNMENT; + else + alignment = GET_MODE_ALIGNMENT (mode); + + /* Allow the frond-end to (possibly) increase the alignment of this + stack slot. */ + if (! type) + type = lang_hooks.types.type_for_mode (mode, 0); + + return STACK_SLOT_ALIGNMENT (type, mode, alignment); +} + +/* Allocate a stack slot of SIZE bytes and return a MEM rtx for it + with machine mode MODE. + + ALIGN controls the amount of alignment for the address of the slot: + 0 means according to MODE, + -1 means use BIGGEST_ALIGNMENT and round size to multiple of that, + -2 means use BITS_PER_UNIT, + positive specifies alignment boundary in bits. + + If REDUCE_ALIGNMENT_OK is true, it is OK to reduce alignment. + + We do not round to stack_boundary here. */ + +rtx +assign_stack_local_1 (enum machine_mode mode, HOST_WIDE_INT size, + int align, + bool reduce_alignment_ok ATTRIBUTE_UNUSED) +{ + rtx x, addr; + int bigend_correction = 0; + unsigned int alignment, alignment_in_bits; + int frame_off, frame_alignment, frame_phase; + + if (align == 0) + { + alignment = get_stack_local_alignment (NULL, mode); + alignment /= BITS_PER_UNIT; + } + else if (align == -1) + { + alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT; + size = CEIL_ROUND (size, alignment); + } + else if (align == -2) + alignment = 1; /* BITS_PER_UNIT / BITS_PER_UNIT */ + else + alignment = align / BITS_PER_UNIT; + + alignment_in_bits = alignment * BITS_PER_UNIT; + + if (FRAME_GROWS_DOWNWARD) + frame_offset -= size; + + /* Ignore alignment if it exceeds MAX_SUPPORTED_STACK_ALIGNMENT. */ + if (alignment_in_bits > MAX_SUPPORTED_STACK_ALIGNMENT) + { + alignment_in_bits = MAX_SUPPORTED_STACK_ALIGNMENT; + alignment = alignment_in_bits / BITS_PER_UNIT; + } + + if (SUPPORTS_STACK_ALIGNMENT) + { + if (crtl->stack_alignment_estimated < alignment_in_bits) + { + if (!crtl->stack_realign_processed) + crtl->stack_alignment_estimated = alignment_in_bits; + else + { + /* If stack is realigned and stack alignment value + hasn't been finalized, it is OK not to increase + stack_alignment_estimated. The bigger alignment + requirement is recorded in stack_alignment_needed + below. */ + gcc_assert (!crtl->stack_realign_finalized); + if (!crtl->stack_realign_needed) + { + /* It is OK to reduce the alignment as long as the + requested size is 0 or the estimated stack + alignment >= mode alignment. */ + gcc_assert (reduce_alignment_ok + || size == 0 + || (crtl->stack_alignment_estimated + >= GET_MODE_ALIGNMENT (mode))); + alignment_in_bits = crtl->stack_alignment_estimated; + alignment = alignment_in_bits / BITS_PER_UNIT; + } + } + } + } + + if (crtl->stack_alignment_needed < alignment_in_bits) + crtl->stack_alignment_needed = alignment_in_bits; + if (crtl->max_used_stack_slot_alignment < crtl->stack_alignment_needed) + crtl->max_used_stack_slot_alignment = crtl->stack_alignment_needed; + + /* Calculate how many bytes the start of local variables is off from + stack alignment. */ + frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT; + frame_off = STARTING_FRAME_OFFSET % frame_alignment; + frame_phase = frame_off ? frame_alignment - frame_off : 0; + + /* Round the frame offset to the specified alignment. The default is + to always honor requests to align the stack but a port may choose to + do its own stack alignment by defining STACK_ALIGNMENT_NEEDED. */ + if (STACK_ALIGNMENT_NEEDED + || mode != BLKmode + || size != 0) + { + /* We must be careful here, since FRAME_OFFSET might be negative and + division with a negative dividend isn't as well defined as we might + like. So we instead assume that ALIGNMENT is a power of two and + use logical operations which are unambiguous. */ + if (FRAME_GROWS_DOWNWARD) + frame_offset + = (FLOOR_ROUND (frame_offset - frame_phase, + (unsigned HOST_WIDE_INT) alignment) + + frame_phase); + else + frame_offset + = (CEIL_ROUND (frame_offset - frame_phase, + (unsigned HOST_WIDE_INT) alignment) + + frame_phase); + } + + /* On a big-endian machine, if we are allocating more space than we will use, + use the least significant bytes of those that are allocated. */ + if (BYTES_BIG_ENDIAN && mode != BLKmode && GET_MODE_SIZE (mode) < size) + bigend_correction = size - GET_MODE_SIZE (mode); + + /* If we have already instantiated virtual registers, return the actual + address relative to the frame pointer. */ + if (virtuals_instantiated) + addr = plus_constant (frame_pointer_rtx, + trunc_int_for_mode + (frame_offset + bigend_correction + + STARTING_FRAME_OFFSET, Pmode)); + else + addr = plus_constant (virtual_stack_vars_rtx, + trunc_int_for_mode + (frame_offset + bigend_correction, + Pmode)); + + if (!FRAME_GROWS_DOWNWARD) + frame_offset += size; + + x = gen_rtx_MEM (mode, addr); + set_mem_align (x, alignment_in_bits); + MEM_NOTRAP_P (x) = 1; + + stack_slot_list + = gen_rtx_EXPR_LIST (VOIDmode, x, stack_slot_list); + + if (frame_offset_overflow (frame_offset, current_function_decl)) + frame_offset = 0; + + return x; +} + +/* Wrap up assign_stack_local_1 with last parameter as false. */ + +rtx +assign_stack_local (enum machine_mode mode, HOST_WIDE_INT size, int align) +{ + return assign_stack_local_1 (mode, size, align, false); +} + + +/* In order to evaluate some expressions, such as function calls returning + structures in memory, we need to temporarily allocate stack locations. + We record each allocated temporary in the following structure. + + Associated with each temporary slot is a nesting level. When we pop up + one level, all temporaries associated with the previous level are freed. + Normally, all temporaries are freed after the execution of the statement + in which they were created. However, if we are inside a ({...}) grouping, + the result may be in a temporary and hence must be preserved. If the + result could be in a temporary, we preserve it if we can determine which + one it is in. If we cannot determine which temporary may contain the + result, all temporaries are preserved. A temporary is preserved by + pretending it was allocated at the previous nesting level. + + Automatic variables are also assigned temporary slots, at the nesting + level where they are defined. They are marked a "kept" so that + free_temp_slots will not free them. */ + +struct temp_slot GTY(()) +{ + /* Points to next temporary slot. */ + struct temp_slot *next; + /* Points to previous temporary slot. */ + struct temp_slot *prev; + /* The rtx to used to reference the slot. */ + rtx slot; + /* The size, in units, of the slot. */ + HOST_WIDE_INT size; + /* The type of the object in the slot, or zero if it doesn't correspond + to a type. We use this to determine whether a slot can be reused. + It can be reused if objects of the type of the new slot will always + conflict with objects of the type of the old slot. */ + tree type; + /* The alignment (in bits) of the slot. */ + unsigned int align; + /* Nonzero if this temporary is currently in use. */ + char in_use; + /* Nonzero if this temporary has its address taken. */ + char addr_taken; + /* Nesting level at which this slot is being used. */ + int level; + /* Nonzero if this should survive a call to free_temp_slots. */ + int keep; + /* The offset of the slot from the frame_pointer, including extra space + for alignment. This info is for combine_temp_slots. */ + HOST_WIDE_INT base_offset; + /* The size of the slot, including extra space for alignment. This + info is for combine_temp_slots. */ + HOST_WIDE_INT full_size; +}; + +/* A table of addresses that represent a stack slot. The table is a mapping + from address RTXen to a temp slot. */ +static GTY((param_is(struct temp_slot_address_entry))) htab_t temp_slot_address_table; + +/* Entry for the above hash table. */ +struct temp_slot_address_entry GTY(()) +{ + hashval_t hash; + rtx address; + struct temp_slot *temp_slot; +}; + +/* Removes temporary slot TEMP from LIST. */ + +static void +cut_slot_from_list (struct temp_slot *temp, struct temp_slot **list) +{ + if (temp->next) + temp->next->prev = temp->prev; + if (temp->prev) + temp->prev->next = temp->next; + else + *list = temp->next; + + temp->prev = temp->next = NULL; +} + +/* Inserts temporary slot TEMP to LIST. */ + +static void +insert_slot_to_list (struct temp_slot *temp, struct temp_slot **list) +{ + temp->next = *list; + if (*list) + (*list)->prev = temp; + temp->prev = NULL; + *list = temp; +} + +/* Returns the list of used temp slots at LEVEL. */ + +static struct temp_slot ** +temp_slots_at_level (int level) +{ + if (level >= (int) VEC_length (temp_slot_p, used_temp_slots)) + VEC_safe_grow_cleared (temp_slot_p, gc, used_temp_slots, level + 1); + + return &(VEC_address (temp_slot_p, used_temp_slots)[level]); +} + +/* Returns the maximal temporary slot level. */ + +static int +max_slot_level (void) +{ + if (!used_temp_slots) + return -1; + + return VEC_length (temp_slot_p, used_temp_slots) - 1; +} + +/* Moves temporary slot TEMP to LEVEL. */ + +static void +move_slot_to_level (struct temp_slot *temp, int level) +{ + cut_slot_from_list (temp, temp_slots_at_level (temp->level)); + insert_slot_to_list (temp, temp_slots_at_level (level)); + temp->level = level; +} + +/* Make temporary slot TEMP available. */ + +static void +make_slot_available (struct temp_slot *temp) +{ + cut_slot_from_list (temp, temp_slots_at_level (temp->level)); + insert_slot_to_list (temp, &avail_temp_slots); + temp->in_use = 0; + temp->level = -1; +} + +/* Compute the hash value for an address -> temp slot mapping. + The value is cached on the mapping entry. */ +static hashval_t +temp_slot_address_compute_hash (struct temp_slot_address_entry *t) +{ + int do_not_record = 0; + return hash_rtx (t->address, GET_MODE (t->address), + &do_not_record, NULL, false); +} + +/* Return the hash value for an address -> temp slot mapping. */ +static hashval_t +temp_slot_address_hash (const void *p) +{ + const struct temp_slot_address_entry *t; + t = (const struct temp_slot_address_entry *) p; + return t->hash; +} + +/* Compare two address -> temp slot mapping entries. */ +static int +temp_slot_address_eq (const void *p1, const void *p2) +{ + const struct temp_slot_address_entry *t1, *t2; + t1 = (const struct temp_slot_address_entry *) p1; + t2 = (const struct temp_slot_address_entry *) p2; + return exp_equiv_p (t1->address, t2->address, 0, true); +} + +/* Add ADDRESS as an alias of TEMP_SLOT to the addess -> temp slot mapping. */ +static void +insert_temp_slot_address (rtx address, struct temp_slot *temp_slot) +{ + void **slot; + struct temp_slot_address_entry *t = GGC_NEW (struct temp_slot_address_entry); + t->address = address; + t->temp_slot = temp_slot; + t->hash = temp_slot_address_compute_hash (t); + slot = htab_find_slot_with_hash (temp_slot_address_table, t, t->hash, INSERT); + *slot = t; +} + +/* Remove an address -> temp slot mapping entry if the temp slot is + not in use anymore. Callback for remove_unused_temp_slot_addresses. */ +static int +remove_unused_temp_slot_addresses_1 (void **slot, void *data ATTRIBUTE_UNUSED) +{ + const struct temp_slot_address_entry *t; + t = (const struct temp_slot_address_entry *) *slot; + if (! t->temp_slot->in_use) + *slot = NULL; + return 1; +} + +/* Remove all mappings of addresses to unused temp slots. */ +static void +remove_unused_temp_slot_addresses (void) +{ + htab_traverse (temp_slot_address_table, + remove_unused_temp_slot_addresses_1, + NULL); +} + +/* Find the temp slot corresponding to the object at address X. */ + +static struct temp_slot * +find_temp_slot_from_address (rtx x) +{ + struct temp_slot *p; + struct temp_slot_address_entry tmp, *t; + + /* First try the easy way: + See if X exists in the address -> temp slot mapping. */ + tmp.address = x; + tmp.temp_slot = NULL; + tmp.hash = temp_slot_address_compute_hash (&tmp); + t = (struct temp_slot_address_entry *) + htab_find_with_hash (temp_slot_address_table, &tmp, tmp.hash); + if (t) + return t->temp_slot; + + /* If we have a sum involving a register, see if it points to a temp + slot. */ + if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 0)) + && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0) + return p; + else if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 1)) + && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0) + return p; + + /* Last resort: Address is a virtual stack var address. */ + if (GET_CODE (x) == PLUS + && XEXP (x, 0) == virtual_stack_vars_rtx + && GET_CODE (XEXP (x, 1)) == CONST_INT) + { + int i; + for (i = max_slot_level (); i >= 0; i--) + for (p = *temp_slots_at_level (i); p; p = p->next) + { + if (INTVAL (XEXP (x, 1)) >= p->base_offset + && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size) + return p; + } + } + + return NULL; +} + +/* Allocate a temporary stack slot and record it for possible later + reuse. + + MODE is the machine mode to be given to the returned rtx. + + SIZE is the size in units of the space required. We do no rounding here + since assign_stack_local will do any required rounding. + + KEEP is 1 if this slot is to be retained after a call to + free_temp_slots. Automatic variables for a block are allocated + with this flag. KEEP values of 2 or 3 were needed respectively + for variables whose lifetime is controlled by CLEANUP_POINT_EXPRs + or for SAVE_EXPRs, but they are now unused. + + TYPE is the type that will be used for the stack slot. */ + +rtx +assign_stack_temp_for_type (enum machine_mode mode, HOST_WIDE_INT size, + int keep, tree type) +{ + unsigned int align; + struct temp_slot *p, *best_p = 0, *selected = NULL, **pp; + rtx slot; + + /* If SIZE is -1 it means that somebody tried to allocate a temporary + of a variable size. */ + gcc_assert (size != -1); + + /* These are now unused. */ + gcc_assert (keep <= 1); + + align = get_stack_local_alignment (type, mode); + + /* Try to find an available, already-allocated temporary of the proper + mode which meets the size and alignment requirements. Choose the + smallest one with the closest alignment. + + If assign_stack_temp is called outside of the tree->rtl expansion, + we cannot reuse the stack slots (that may still refer to + VIRTUAL_STACK_VARS_REGNUM). */ + if (!virtuals_instantiated) + { + for (p = avail_temp_slots; p; p = p->next) + { + if (p->align >= align && p->size >= size + && GET_MODE (p->slot) == mode + && objects_must_conflict_p (p->type, type) + && (best_p == 0 || best_p->size > p->size + || (best_p->size == p->size && best_p->align > p->align))) + { + if (p->align == align && p->size == size) + { + selected = p; + cut_slot_from_list (selected, &avail_temp_slots); + best_p = 0; + break; + } + best_p = p; + } + } + } + + /* Make our best, if any, the one to use. */ + if (best_p) + { + selected = best_p; + cut_slot_from_list (selected, &avail_temp_slots); + + /* If there are enough aligned bytes left over, make them into a new + temp_slot so that the extra bytes don't get wasted. Do this only + for BLKmode slots, so that we can be sure of the alignment. */ + if (GET_MODE (best_p->slot) == BLKmode) + { + int alignment = best_p->align / BITS_PER_UNIT; + HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment); + + if (best_p->size - rounded_size >= alignment) + { + p = GGC_NEW (struct temp_slot); + p->in_use = p->addr_taken = 0; + p->size = best_p->size - rounded_size; + p->base_offset = best_p->base_offset + rounded_size; + p->full_size = best_p->full_size - rounded_size; + p->slot = adjust_address_nv (best_p->slot, BLKmode, rounded_size); + p->align = best_p->align; + p->type = best_p->type; + insert_slot_to_list (p, &avail_temp_slots); + + stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot, + stack_slot_list); + + best_p->size = rounded_size; + best_p->full_size = rounded_size; + } + } + } + + /* If we still didn't find one, make a new temporary. */ + if (selected == 0) + { + HOST_WIDE_INT frame_offset_old = frame_offset; + + p = GGC_NEW (struct temp_slot); + + /* We are passing an explicit alignment request to assign_stack_local. + One side effect of that is assign_stack_local will not round SIZE + to ensure the frame offset remains suitably aligned. + + So for requests which depended on the rounding of SIZE, we go ahead + and round it now. We also make sure ALIGNMENT is at least + BIGGEST_ALIGNMENT. */ + gcc_assert (mode != BLKmode || align == BIGGEST_ALIGNMENT); + p->slot = assign_stack_local (mode, + (mode == BLKmode + ? CEIL_ROUND (size, (int) align / BITS_PER_UNIT) + : size), + align); + + p->align = align; + + /* The following slot size computation is necessary because we don't + know the actual size of the temporary slot until assign_stack_local + has performed all the frame alignment and size rounding for the + requested temporary. Note that extra space added for alignment + can be either above or below this stack slot depending on which + way the frame grows. We include the extra space if and only if it + is above this slot. */ + if (FRAME_GROWS_DOWNWARD) + p->size = frame_offset_old - frame_offset; + else + p->size = size; + + /* Now define the fields used by combine_temp_slots. */ + if (FRAME_GROWS_DOWNWARD) + { + p->base_offset = frame_offset; + p->full_size = frame_offset_old - frame_offset; + } + else + { + p->base_offset = frame_offset_old; + p->full_size = frame_offset - frame_offset_old; + } + + selected = p; + } + + p = selected; + p->in_use = 1; + p->addr_taken = 0; + p->type = type; + p->level = temp_slot_level; + p->keep = keep; + + pp = temp_slots_at_level (p->level); + insert_slot_to_list (p, pp); + insert_temp_slot_address (XEXP (p->slot, 0), p); + + /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */ + slot = gen_rtx_MEM (mode, XEXP (p->slot, 0)); + stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, slot, stack_slot_list); + + /* If we know the alias set for the memory that will be used, use + it. If there's no TYPE, then we don't know anything about the + alias set for the memory. */ + set_mem_alias_set (slot, type ? get_alias_set (type) : 0); + set_mem_align (slot, align); + + /* If a type is specified, set the relevant flags. */ + if (type != 0) + { + MEM_VOLATILE_P (slot) = TYPE_VOLATILE (type); + MEM_SET_IN_STRUCT_P (slot, (AGGREGATE_TYPE_P (type) + || TREE_CODE (type) == COMPLEX_TYPE)); + } + MEM_NOTRAP_P (slot) = 1; + + return slot; +} + +/* Allocate a temporary stack slot and record it for possible later + reuse. First three arguments are same as in preceding function. */ + +rtx +assign_stack_temp (enum machine_mode mode, HOST_WIDE_INT size, int keep) +{ + return assign_stack_temp_for_type (mode, size, keep, NULL_TREE); +} + +/* Assign a temporary. + If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl + and so that should be used in error messages. In either case, we + allocate of the given type. + KEEP is as for assign_stack_temp. + MEMORY_REQUIRED is 1 if the result must be addressable stack memory; + it is 0 if a register is OK. + DONT_PROMOTE is 1 if we should not promote values in register + to wider modes. */ + +rtx +assign_temp (tree type_or_decl, int keep, int memory_required, + int dont_promote ATTRIBUTE_UNUSED) +{ + tree type, decl; + enum machine_mode mode; +#ifdef PROMOTE_MODE + int unsignedp; +#endif + + if (DECL_P (type_or_decl)) + decl = type_or_decl, type = TREE_TYPE (decl); + else + decl = NULL, type = type_or_decl; + + mode = TYPE_MODE (type); +#ifdef PROMOTE_MODE + unsignedp = TYPE_UNSIGNED (type); +#endif + + if (mode == BLKmode || memory_required) + { + HOST_WIDE_INT size = int_size_in_bytes (type); + rtx tmp; + + /* Zero sized arrays are GNU C extension. Set size to 1 to avoid + problems with allocating the stack space. */ + if (size == 0) + size = 1; + + /* Unfortunately, we don't yet know how to allocate variable-sized + temporaries. However, sometimes we can find a fixed upper limit on + the size, so try that instead. */ + else if (size == -1) + size = max_int_size_in_bytes (type); + + /* The size of the temporary may be too large to fit into an integer. */ + /* ??? Not sure this should happen except for user silliness, so limit + this to things that aren't compiler-generated temporaries. The + rest of the time we'll die in assign_stack_temp_for_type. */ + if (decl && size == -1 + && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST) + { + error ("size of variable %q+D is too large", decl); + size = 1; + } + + tmp = assign_stack_temp_for_type (mode, size, keep, type); + return tmp; + } + +#ifdef PROMOTE_MODE + if (! dont_promote) + mode = promote_mode (type, mode, &unsignedp, 0); +#endif + + return gen_reg_rtx (mode); +} + +/* Combine temporary stack slots which are adjacent on the stack. + + This allows for better use of already allocated stack space. This is only + done for BLKmode slots because we can be sure that we won't have alignment + problems in this case. */ + +static void +combine_temp_slots (void) +{ + struct temp_slot *p, *q, *next, *next_q; + int num_slots; + + /* We can't combine slots, because the information about which slot + is in which alias set will be lost. */ + if (flag_strict_aliasing) + return; + + /* If there are a lot of temp slots, don't do anything unless + high levels of optimization. */ + if (! flag_expensive_optimizations) + for (p = avail_temp_slots, num_slots = 0; p; p = p->next, num_slots++) + if (num_slots > 100 || (num_slots > 10 && optimize == 0)) + return; + + for (p = avail_temp_slots; p; p = next) + { + int delete_p = 0; + + next = p->next; + + if (GET_MODE (p->slot) != BLKmode) + continue; + + for (q = p->next; q; q = next_q) + { + int delete_q = 0; + + next_q = q->next; + + if (GET_MODE (q->slot) != BLKmode) + continue; + + if (p->base_offset + p->full_size == q->base_offset) + { + /* Q comes after P; combine Q into P. */ + p->size += q->size; + p->full_size += q->full_size; + delete_q = 1; + } + else if (q->base_offset + q->full_size == p->base_offset) + { + /* P comes after Q; combine P into Q. */ + q->size += p->size; + q->full_size += p->full_size; + delete_p = 1; + break; + } + if (delete_q) + cut_slot_from_list (q, &avail_temp_slots); + } + + /* Either delete P or advance past it. */ + if (delete_p) + cut_slot_from_list (p, &avail_temp_slots); + } +} + +/* Indicate that NEW_RTX is an alternate way of referring to the temp + slot that previously was known by OLD_RTX. */ + +void +update_temp_slot_address (rtx old_rtx, rtx new_rtx) +{ + struct temp_slot *p; + + if (rtx_equal_p (old_rtx, new_rtx)) + return; + + p = find_temp_slot_from_address (old_rtx); + + /* If we didn't find one, see if both OLD_RTX is a PLUS. If so, and + NEW_RTX is a register, see if one operand of the PLUS is a + temporary location. If so, NEW_RTX points into it. Otherwise, + if both OLD_RTX and NEW_RTX are a PLUS and if there is a register + in common between them. If so, try a recursive call on those + values. */ + if (p == 0) + { + if (GET_CODE (old_rtx) != PLUS) + return; + + if (REG_P (new_rtx)) + { + update_temp_slot_address (XEXP (old_rtx, 0), new_rtx); + update_temp_slot_address (XEXP (old_rtx, 1), new_rtx); + return; + } + else if (GET_CODE (new_rtx) != PLUS) + return; + + if (rtx_equal_p (XEXP (old_rtx, 0), XEXP (new_rtx, 0))) + update_temp_slot_address (XEXP (old_rtx, 1), XEXP (new_rtx, 1)); + else if (rtx_equal_p (XEXP (old_rtx, 1), XEXP (new_rtx, 0))) + update_temp_slot_address (XEXP (old_rtx, 0), XEXP (new_rtx, 1)); + else if (rtx_equal_p (XEXP (old_rtx, 0), XEXP (new_rtx, 1))) + update_temp_slot_address (XEXP (old_rtx, 1), XEXP (new_rtx, 0)); + else if (rtx_equal_p (XEXP (old_rtx, 1), XEXP (new_rtx, 1))) + update_temp_slot_address (XEXP (old_rtx, 0), XEXP (new_rtx, 0)); + + return; + } + + /* Otherwise add an alias for the temp's address. */ + insert_temp_slot_address (new_rtx, p); +} + +/* If X could be a reference to a temporary slot, mark the fact that its + address was taken. */ + +void +mark_temp_addr_taken (rtx x) +{ + struct temp_slot *p; + + if (x == 0) + return; + + /* If X is not in memory or is at a constant address, it cannot be in + a temporary slot. */ + if (!MEM_P (x) || CONSTANT_P (XEXP (x, 0))) + return; + + p = find_temp_slot_from_address (XEXP (x, 0)); + if (p != 0) + p->addr_taken = 1; +} + +/* If X could be a reference to a temporary slot, mark that slot as + belonging to the to one level higher than the current level. If X + matched one of our slots, just mark that one. Otherwise, we can't + easily predict which it is, so upgrade all of them. Kept slots + need not be touched. + + This is called when an ({...}) construct occurs and a statement + returns a value in memory. */ + +void +preserve_temp_slots (rtx x) +{ + struct temp_slot *p = 0, *next; + + /* If there is no result, we still might have some objects whose address + were taken, so we need to make sure they stay around. */ + if (x == 0) + { + for (p = *temp_slots_at_level (temp_slot_level); p; p = next) + { + next = p->next; + + if (p->addr_taken) + move_slot_to_level (p, temp_slot_level - 1); + } + + return; + } + + /* If X is a register that is being used as a pointer, see if we have + a temporary slot we know it points to. To be consistent with + the code below, we really should preserve all non-kept slots + if we can't find a match, but that seems to be much too costly. */ + if (REG_P (x) && REG_POINTER (x)) + p = find_temp_slot_from_address (x); + + /* If X is not in memory or is at a constant address, it cannot be in + a temporary slot, but it can contain something whose address was + taken. */ + if (p == 0 && (!MEM_P (x) || CONSTANT_P (XEXP (x, 0)))) + { + for (p = *temp_slots_at_level (temp_slot_level); p; p = next) + { + next = p->next; + + if (p->addr_taken) + move_slot_to_level (p, temp_slot_level - 1); + } + + return; + } + + /* First see if we can find a match. */ + if (p == 0) + p = find_temp_slot_from_address (XEXP (x, 0)); + + if (p != 0) + { + /* Move everything at our level whose address was taken to our new + level in case we used its address. */ + struct temp_slot *q; + + if (p->level == temp_slot_level) + { + for (q = *temp_slots_at_level (temp_slot_level); q; q = next) + { + next = q->next; + + if (p != q && q->addr_taken) + move_slot_to_level (q, temp_slot_level - 1); + } + + move_slot_to_level (p, temp_slot_level - 1); + p->addr_taken = 0; + } + return; + } + + /* Otherwise, preserve all non-kept slots at this level. */ + for (p = *temp_slots_at_level (temp_slot_level); p; p = next) + { + next = p->next; + + if (!p->keep) + move_slot_to_level (p, temp_slot_level - 1); + } +} + +/* Free all temporaries used so far. This is normally called at the + end of generating code for a statement. */ + +void +free_temp_slots (void) +{ + struct temp_slot *p, *next; + + for (p = *temp_slots_at_level (temp_slot_level); p; p = next) + { + next = p->next; + + if (!p->keep) + make_slot_available (p); + } + + remove_unused_temp_slot_addresses (); + combine_temp_slots (); +} + +/* Push deeper into the nesting level for stack temporaries. */ + +void +push_temp_slots (void) +{ + temp_slot_level++; +} + +/* Pop a temporary nesting level. All slots in use in the current level + are freed. */ + +void +pop_temp_slots (void) +{ + struct temp_slot *p, *next; + + for (p = *temp_slots_at_level (temp_slot_level); p; p = next) + { + next = p->next; + make_slot_available (p); + } + + remove_unused_temp_slot_addresses (); + combine_temp_slots (); + + temp_slot_level--; +} + +/* Initialize temporary slots. */ + +void +init_temp_slots (void) +{ + /* We have not allocated any temporaries yet. */ + avail_temp_slots = 0; + used_temp_slots = 0; + temp_slot_level = 0; + + /* Set up the table to map addresses to temp slots. */ + if (! temp_slot_address_table) + temp_slot_address_table = htab_create_ggc (32, + temp_slot_address_hash, + temp_slot_address_eq, + NULL); + else + htab_empty (temp_slot_address_table); +} + +/* These routines are responsible for converting virtual register references + to the actual hard register references once RTL generation is complete. + + The following four variables are used for communication between the + routines. They contain the offsets of the virtual registers from their + respective hard registers. */ + +static int in_arg_offset; +static int var_offset; +static int dynamic_offset; +static int out_arg_offset; +static int cfa_offset; + +/* In most machines, the stack pointer register is equivalent to the bottom + of the stack. */ + +#ifndef STACK_POINTER_OFFSET +#define STACK_POINTER_OFFSET 0 +#endif + +/* If not defined, pick an appropriate default for the offset of dynamically + allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS, + REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */ + +#ifndef STACK_DYNAMIC_OFFSET + +/* The bottom of the stack points to the actual arguments. If + REG_PARM_STACK_SPACE is defined, this includes the space for the register + parameters. However, if OUTGOING_REG_PARM_STACK space is not defined, + stack space for register parameters is not pushed by the caller, but + rather part of the fixed stack areas and hence not included in + `crtl->outgoing_args_size'. Nevertheless, we must allow + for it when allocating stack dynamic objects. */ + +#if defined(REG_PARM_STACK_SPACE) +#define STACK_DYNAMIC_OFFSET(FNDECL) \ +((ACCUMULATE_OUTGOING_ARGS \ + ? (crtl->outgoing_args_size \ + + (OUTGOING_REG_PARM_STACK_SPACE ((!(FNDECL) ? NULL_TREE : TREE_TYPE (FNDECL))) ? 0 \ + : REG_PARM_STACK_SPACE (FNDECL))) \ + : 0) + (STACK_POINTER_OFFSET)) +#else +#define STACK_DYNAMIC_OFFSET(FNDECL) \ +((ACCUMULATE_OUTGOING_ARGS ? crtl->outgoing_args_size : 0) \ + + (STACK_POINTER_OFFSET)) +#endif +#endif + + +/* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX + is a virtual register, return the equivalent hard register and set the + offset indirectly through the pointer. Otherwise, return 0. */ + +static rtx +instantiate_new_reg (rtx x, HOST_WIDE_INT *poffset) +{ + rtx new_rtx; + HOST_WIDE_INT offset; + + if (x == virtual_incoming_args_rtx) + { + if (stack_realign_drap) + { + /* Replace virtual_incoming_args_rtx with internal arg + pointer if DRAP is used to realign stack. */ + new_rtx = crtl->args.internal_arg_pointer; + offset = 0; + } + else + new_rtx = arg_pointer_rtx, offset = in_arg_offset; + } + else if (x == virtual_stack_vars_rtx) + new_rtx = frame_pointer_rtx, offset = var_offset; + else if (x == virtual_stack_dynamic_rtx) + new_rtx = stack_pointer_rtx, offset = dynamic_offset; + else if (x == virtual_outgoing_args_rtx) + new_rtx = stack_pointer_rtx, offset = out_arg_offset; + else if (x == virtual_cfa_rtx) + { +#ifdef FRAME_POINTER_CFA_OFFSET + new_rtx = frame_pointer_rtx; +#else + new_rtx = arg_pointer_rtx; +#endif + offset = cfa_offset; + } + else + return NULL_RTX; + + *poffset = offset; + return new_rtx; +} + +/* A subroutine of instantiate_virtual_regs, called via for_each_rtx. + Instantiate any virtual registers present inside of *LOC. The expression + is simplified, as much as possible, but is not to be considered "valid" + in any sense implied by the target. If any change is made, set CHANGED + to true. */ + +static int +instantiate_virtual_regs_in_rtx (rtx *loc, void *data) +{ + HOST_WIDE_INT offset; + bool *changed = (bool *) data; + rtx x, new_rtx; + + x = *loc; + if (x == 0) + return 0; + + switch (GET_CODE (x)) + { + case REG: + new_rtx = instantiate_new_reg (x, &offset); + if (new_rtx) + { + *loc = plus_constant (new_rtx, offset); + if (changed) + *changed = true; + } + return -1; + + case PLUS: + new_rtx = instantiate_new_reg (XEXP (x, 0), &offset); + if (new_rtx) + { + new_rtx = plus_constant (new_rtx, offset); + *loc = simplify_gen_binary (PLUS, GET_MODE (x), new_rtx, XEXP (x, 1)); + if (changed) + *changed = true; + return -1; + } + + /* FIXME -- from old code */ + /* If we have (plus (subreg (virtual-reg)) (const_int)), we know + we can commute the PLUS and SUBREG because pointers into the + frame are well-behaved. */ + break; + + default: + break; + } + + return 0; +} + +/* A subroutine of instantiate_virtual_regs_in_insn. Return true if X + matches the predicate for insn CODE operand OPERAND. */ + +static int +safe_insn_predicate (int code, int operand, rtx x) +{ + const struct insn_operand_data *op_data; + + if (code < 0) + return true; + + op_data = &insn_data[code].operand[operand]; + if (op_data->predicate == NULL) + return true; + + return op_data->predicate (x, op_data->mode); +} + +/* A subroutine of instantiate_virtual_regs. Instantiate any virtual + registers present inside of insn. The result will be a valid insn. */ + +static void +instantiate_virtual_regs_in_insn (rtx insn) +{ + HOST_WIDE_INT offset; + int insn_code, i; + bool any_change = false; + rtx set, new_rtx, x, seq; + + /* There are some special cases to be handled first. */ + set = single_set (insn); + if (set) + { + /* We're allowed to assign to a virtual register. This is interpreted + to mean that the underlying register gets assigned the inverse + transformation. This is used, for example, in the handling of + non-local gotos. */ + new_rtx = instantiate_new_reg (SET_DEST (set), &offset); + if (new_rtx) + { + start_sequence (); + + for_each_rtx (&SET_SRC (set), instantiate_virtual_regs_in_rtx, NULL); + x = simplify_gen_binary (PLUS, GET_MODE (new_rtx), SET_SRC (set), + GEN_INT (-offset)); + x = force_operand (x, new_rtx); + if (x != new_rtx) + emit_move_insn (new_rtx, x); + + seq = get_insns (); + end_sequence (); + + emit_insn_before (seq, insn); + delete_insn (insn); + return; + } + + /* Handle a straight copy from a virtual register by generating a + new add insn. The difference between this and falling through + to the generic case is avoiding a new pseudo and eliminating a + move insn in the initial rtl stream. */ + new_rtx = instantiate_new_reg (SET_SRC (set), &offset); + if (new_rtx && offset != 0 + && REG_P (SET_DEST (set)) + && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER) + { + start_sequence (); + + x = expand_simple_binop (GET_MODE (SET_DEST (set)), PLUS, + new_rtx, GEN_INT (offset), SET_DEST (set), + 1, OPTAB_LIB_WIDEN); + if (x != SET_DEST (set)) + emit_move_insn (SET_DEST (set), x); + + seq = get_insns (); + end_sequence (); + + emit_insn_before (seq, insn); + delete_insn (insn); + return; + } + + extract_insn (insn); + insn_code = INSN_CODE (insn); + + /* Handle a plus involving a virtual register by determining if the + operands remain valid if they're modified in place. */ + if (GET_CODE (SET_SRC (set)) == PLUS + && recog_data.n_operands >= 3 + && recog_data.operand_loc[1] == &XEXP (SET_SRC (set), 0) + && recog_data.operand_loc[2] == &XEXP (SET_SRC (set), 1) + && GET_CODE (recog_data.operand[2]) == CONST_INT + && (new_rtx = instantiate_new_reg (recog_data.operand[1], &offset))) + { + offset += INTVAL (recog_data.operand[2]); + + /* If the sum is zero, then replace with a plain move. */ + if (offset == 0 + && REG_P (SET_DEST (set)) + && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER) + { + start_sequence (); + emit_move_insn (SET_DEST (set), new_rtx); + seq = get_insns (); + end_sequence (); + + emit_insn_before (seq, insn); + delete_insn (insn); + return; + } + + x = gen_int_mode (offset, recog_data.operand_mode[2]); + + /* Using validate_change and apply_change_group here leaves + recog_data in an invalid state. Since we know exactly what + we want to check, do those two by hand. */ + if (safe_insn_predicate (insn_code, 1, new_rtx) + && safe_insn_predicate (insn_code, 2, x)) + { + *recog_data.operand_loc[1] = recog_data.operand[1] = new_rtx; + *recog_data.operand_loc[2] = recog_data.operand[2] = x; + any_change = true; + + /* Fall through into the regular operand fixup loop in + order to take care of operands other than 1 and 2. */ + } + } + } + else + { + extract_insn (insn); + insn_code = INSN_CODE (insn); + } + + /* In the general case, we expect virtual registers to appear only in + operands, and then only as either bare registers or inside memories. */ + for (i = 0; i < recog_data.n_operands; ++i) + { + x = recog_data.operand[i]; + switch (GET_CODE (x)) + { + case MEM: + { + rtx addr = XEXP (x, 0); + bool changed = false; + + for_each_rtx (&addr, instantiate_virtual_regs_in_rtx, &changed); + if (!changed) + continue; + + start_sequence (); + x = replace_equiv_address (x, addr); + /* It may happen that the address with the virtual reg + was valid (e.g. based on the virtual stack reg, which might + be acceptable to the predicates with all offsets), whereas + the address now isn't anymore, for instance when the address + is still offsetted, but the base reg isn't virtual-stack-reg + anymore. Below we would do a force_reg on the whole operand, + but this insn might actually only accept memory. Hence, + before doing that last resort, try to reload the address into + a register, so this operand stays a MEM. */ + if (!safe_insn_predicate (insn_code, i, x)) + { + addr = force_reg (GET_MODE (addr), addr); + x = replace_equiv_address (x, addr); + } + seq = get_insns (); + end_sequence (); + if (seq) + emit_insn_before (seq, insn); + } + break; + + case REG: + new_rtx = instantiate_new_reg (x, &offset); + if (new_rtx == NULL) + continue; + if (offset == 0) + x = new_rtx; + else + { + start_sequence (); + + /* Careful, special mode predicates may have stuff in + insn_data[insn_code].operand[i].mode that isn't useful + to us for computing a new value. */ + /* ??? Recognize address_operand and/or "p" constraints + to see if (plus new offset) is a valid before we put + this through expand_simple_binop. */ + x = expand_simple_binop (GET_MODE (x), PLUS, new_rtx, + GEN_INT (offset), NULL_RTX, + 1, OPTAB_LIB_WIDEN); + seq = get_insns (); + end_sequence (); + emit_insn_before (seq, insn); + } + break; + + case SUBREG: + new_rtx = instantiate_new_reg (SUBREG_REG (x), &offset); + if (new_rtx == NULL) + continue; + if (offset != 0) + { + start_sequence (); + new_rtx = expand_simple_binop (GET_MODE (new_rtx), PLUS, new_rtx, + GEN_INT (offset), NULL_RTX, + 1, OPTAB_LIB_WIDEN); + seq = get_insns (); + end_sequence (); + emit_insn_before (seq, insn); + } + x = simplify_gen_subreg (recog_data.operand_mode[i], new_rtx, + GET_MODE (new_rtx), SUBREG_BYTE (x)); + gcc_assert (x); + break; + + default: + continue; + } + + /* At this point, X contains the new value for the operand. + Validate the new value vs the insn predicate. Note that + asm insns will have insn_code -1 here. */ + if (!safe_insn_predicate (insn_code, i, x)) + { + start_sequence (); + x = force_reg (insn_data[insn_code].operand[i].mode, x); + seq = get_insns (); + end_sequence (); + if (seq) + emit_insn_before (seq, insn); + } + + *recog_data.operand_loc[i] = recog_data.operand[i] = x; + any_change = true; + } + + if (any_change) + { + /* Propagate operand changes into the duplicates. */ + for (i = 0; i < recog_data.n_dups; ++i) + *recog_data.dup_loc[i] + = copy_rtx (recog_data.operand[(unsigned)recog_data.dup_num[i]]); + + /* Force re-recognition of the instruction for validation. */ + INSN_CODE (insn) = -1; + } + + if (asm_noperands (PATTERN (insn)) >= 0) + { + if (!check_asm_operands (PATTERN (insn))) + { + error_for_asm (insn, "impossible constraint in %<asm%>"); + delete_insn (insn); + } + } + else + { + if (recog_memoized (insn) < 0) + fatal_insn_not_found (insn); + } +} + +/* Subroutine of instantiate_decls. Given RTL representing a decl, + do any instantiation required. */ + +void +instantiate_decl_rtl (rtx x) +{ + rtx addr; + + if (x == 0) + return; + + /* If this is a CONCAT, recurse for the pieces. */ + if (GET_CODE (x) == CONCAT) + { + instantiate_decl_rtl (XEXP (x, 0)); + instantiate_decl_rtl (XEXP (x, 1)); + return; + } + + /* If this is not a MEM, no need to do anything. Similarly if the + address is a constant or a register that is not a virtual register. */ + if (!MEM_P (x)) + return; + + addr = XEXP (x, 0); + if (CONSTANT_P (addr) + || (REG_P (addr) + && (REGNO (addr) < FIRST_VIRTUAL_REGISTER + || REGNO (addr) > LAST_VIRTUAL_REGISTER))) + return; + + for_each_rtx (&XEXP (x, 0), instantiate_virtual_regs_in_rtx, NULL); +} + +/* Helper for instantiate_decls called via walk_tree: Process all decls + in the given DECL_VALUE_EXPR. */ + +static tree +instantiate_expr (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED) +{ + tree t = *tp; + if (! EXPR_P (t)) + { + *walk_subtrees = 0; + if (DECL_P (t) && DECL_RTL_SET_P (t)) + instantiate_decl_rtl (DECL_RTL (t)); + } + return NULL; +} + +/* Subroutine of instantiate_decls: Process all decls in the given + BLOCK node and all its subblocks. */ + +static void +instantiate_decls_1 (tree let) +{ + tree t; + + for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t)) + { + if (DECL_RTL_SET_P (t)) + instantiate_decl_rtl (DECL_RTL (t)); + if (TREE_CODE (t) == VAR_DECL && DECL_HAS_VALUE_EXPR_P (t)) + { + tree v = DECL_VALUE_EXPR (t); + walk_tree (&v, instantiate_expr, NULL, NULL); + } + } + + /* Process all subblocks. */ + for (t = BLOCK_SUBBLOCKS (let); t; t = BLOCK_CHAIN (t)) + instantiate_decls_1 (t); +} + +/* Scan all decls in FNDECL (both variables and parameters) and instantiate + all virtual registers in their DECL_RTL's. */ + +static void +instantiate_decls (tree fndecl) +{ + tree decl, t, next; + + /* Process all parameters of the function. */ + for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl)) + { + instantiate_decl_rtl (DECL_RTL (decl)); + instantiate_decl_rtl (DECL_INCOMING_RTL (decl)); + if (DECL_HAS_VALUE_EXPR_P (decl)) + { + tree v = DECL_VALUE_EXPR (decl); + walk_tree (&v, instantiate_expr, NULL, NULL); + } + } + + /* Now process all variables defined in the function or its subblocks. */ + instantiate_decls_1 (DECL_INITIAL (fndecl)); + + t = cfun->local_decls; + cfun->local_decls = NULL_TREE; + for (; t; t = next) + { + next = TREE_CHAIN (t); + decl = TREE_VALUE (t); + if (DECL_RTL_SET_P (decl)) + instantiate_decl_rtl (DECL_RTL (decl)); + ggc_free (t); + } +} + +/* Pass through the INSNS of function FNDECL and convert virtual register + references to hard register references. */ + +static unsigned int +instantiate_virtual_regs (void) +{ + rtx insn; + + /* Compute the offsets to use for this function. */ + in_arg_offset = FIRST_PARM_OFFSET (current_function_decl); + var_offset = STARTING_FRAME_OFFSET; + dynamic_offset = STACK_DYNAMIC_OFFSET (current_function_decl); + out_arg_offset = STACK_POINTER_OFFSET; +#ifdef FRAME_POINTER_CFA_OFFSET + cfa_offset = FRAME_POINTER_CFA_OFFSET (current_function_decl); +#else + cfa_offset = ARG_POINTER_CFA_OFFSET (current_function_decl); +#endif + + /* Initialize recognition, indicating that volatile is OK. */ + init_recog (); + + /* Scan through all the insns, instantiating every virtual register still + present. */ + for (insn = get_insns (); insn; insn = NEXT_INSN (insn)) + if (INSN_P (insn)) + { + /* These patterns in the instruction stream can never be recognized. + Fortunately, they shouldn't contain virtual registers either. */ + if (GET_CODE (PATTERN (insn)) == USE + || GET_CODE (PATTERN (insn)) == CLOBBER + || GET_CODE (PATTERN (insn)) == ADDR_VEC + || GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC + || GET_CODE (PATTERN (insn)) == ASM_INPUT) + continue; + + instantiate_virtual_regs_in_insn (insn); + + if (INSN_DELETED_P (insn)) + continue; + + for_each_rtx (®_NOTES (insn), instantiate_virtual_regs_in_rtx, NULL); + + /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */ + if (GET_CODE (insn) == CALL_INSN) + for_each_rtx (&CALL_INSN_FUNCTION_USAGE (insn), + instantiate_virtual_regs_in_rtx, NULL); + } + + /* Instantiate the virtual registers in the DECLs for debugging purposes. */ + instantiate_decls (current_function_decl); + + targetm.instantiate_decls (); + + /* Indicate that, from now on, assign_stack_local should use + frame_pointer_rtx. */ + virtuals_instantiated = 1; + return 0; +} + +struct rtl_opt_pass pass_instantiate_virtual_regs = +{ + { + RTL_PASS, + "vregs", /* name */ + NULL, /* gate */ + instantiate_virtual_regs, /* execute */ + NULL, /* sub */ + NULL, /* next */ + 0, /* static_pass_number */ + 0, /* tv_id */ + 0, /* properties_required */ + 0, /* properties_provided */ + 0, /* properties_destroyed */ + 0, /* todo_flags_start */ + TODO_dump_func /* todo_flags_finish */ + } +}; + + +/* Return 1 if EXP is an aggregate type (or a value with aggregate type). + This means a type for which function calls must pass an address to the + function or get an address back from the function. + EXP may be a type node or an expression (whose type is tested). */ + +int +aggregate_value_p (const_tree exp, const_tree fntype) +{ + int i, regno, nregs; + rtx reg; + + const_tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp); + + /* DECL node associated with FNTYPE when relevant, which we might need to + check for by-invisible-reference returns, typically for CALL_EXPR input + EXPressions. */ + const_tree fndecl = NULL_TREE; + + if (fntype) + switch (TREE_CODE (fntype)) + { + case CALL_EXPR: + fndecl = get_callee_fndecl (fntype); + fntype = (fndecl + ? TREE_TYPE (fndecl) + : TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (fntype)))); + break; + case FUNCTION_DECL: + fndecl = fntype; + fntype = TREE_TYPE (fndecl); + break; + case FUNCTION_TYPE: + case METHOD_TYPE: + break; + case IDENTIFIER_NODE: + fntype = 0; + break; + default: + /* We don't expect other rtl types here. */ + gcc_unreachable (); + } + + if (TREE_CODE (type) == VOID_TYPE) + return 0; + + /* If the front end has decided that this needs to be passed by + reference, do so. */ + if ((TREE_CODE (exp) == PARM_DECL || TREE_CODE (exp) == RESULT_DECL) + && DECL_BY_REFERENCE (exp)) + return 1; + + /* If the EXPression is a CALL_EXPR, honor DECL_BY_REFERENCE set on the + called function RESULT_DECL, meaning the function returns in memory by + invisible reference. This check lets front-ends not set TREE_ADDRESSABLE + on the function type, which used to be the way to request such a return + mechanism but might now be causing troubles at gimplification time if + temporaries with the function type need to be created. */ + if (TREE_CODE (exp) == CALL_EXPR && fndecl && DECL_RESULT (fndecl) + && DECL_BY_REFERENCE (DECL_RESULT (fndecl))) + return 1; + + if (targetm.calls.return_in_memory (type, fntype)) + return 1; + /* Types that are TREE_ADDRESSABLE must be constructed in memory, + and thus can't be returned in registers. */ + if (TREE_ADDRESSABLE (type)) + return 1; + if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type)) + return 1; + /* Make sure we have suitable call-clobbered regs to return + the value in; if not, we must return it in memory. */ + reg = hard_function_value (type, 0, fntype, 0); + + /* If we have something other than a REG (e.g. a PARALLEL), then assume + it is OK. */ + if (!REG_P (reg)) + return 0; + + regno = REGNO (reg); + nregs = hard_regno_nregs[regno][TYPE_MODE (type)]; + for (i = 0; i < nregs; i++) + if (! call_used_regs[regno + i]) + return 1; + return 0; +} + +/* Return true if we should assign DECL a pseudo register; false if it + should live on the local stack. */ + +bool +use_register_for_decl (const_tree decl) +{ + if (!targetm.calls.allocate_stack_slots_for_args()) + return true; + + /* Honor volatile. */ + if (TREE_SIDE_EFFECTS (decl)) + return false; + + /* Honor addressability. */ + if (TREE_ADDRESSABLE (decl)) + return false; + + /* Only register-like things go in registers. */ + if (DECL_MODE (decl) == BLKmode) + return false; + + /* If -ffloat-store specified, don't put explicit float variables + into registers. */ + /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa + propagates values across these stores, and it probably shouldn't. */ + if (flag_float_store && FLOAT_TYPE_P (TREE_TYPE (decl))) + return false; + + /* If we're not interested in tracking debugging information for + this decl, then we can certainly put it in a register. */ + if (DECL_IGNORED_P (decl)) + return true; + + if (optimize) + return true; + + if (!DECL_REGISTER (decl)) + return false; + + switch (TREE_CODE (TREE_TYPE (decl))) + { + case RECORD_TYPE: + case UNION_TYPE: + case QUAL_UNION_TYPE: + /* When not optimizing, disregard register keyword for variables with + types containing methods, otherwise the methods won't be callable + from the debugger. */ + if (TYPE_METHODS (TREE_TYPE (decl))) + return false; + break; + default: + break; + } + + return true; +} + +/* Return true if TYPE should be passed by invisible reference. */ + +bool +pass_by_reference (CUMULATIVE_ARGS *ca, enum machine_mode mode, + tree type, bool named_arg) +{ + if (type) + { + /* If this type contains non-trivial constructors, then it is + forbidden for the middle-end to create any new copies. */ + if (TREE_ADDRESSABLE (type)) + return true; + + /* GCC post 3.4 passes *all* variable sized types by reference. */ + if (!TYPE_SIZE (type) || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST) + return true; + } + + return targetm.calls.pass_by_reference (ca, mode, type, named_arg); +} + +/* Return true if TYPE, which is passed by reference, should be callee + copied instead of caller copied. */ + +bool +reference_callee_copied (CUMULATIVE_ARGS *ca, enum machine_mode mode, + tree type, bool named_arg) +{ + if (type && TREE_ADDRESSABLE (type)) + return false; + return targetm.calls.callee_copies (ca, mode, type, named_arg); +} + +/* Structures to communicate between the subroutines of assign_parms. + The first holds data persistent across all parameters, the second + is cleared out for each parameter. */ + +struct assign_parm_data_all +{ + CUMULATIVE_ARGS args_so_far; + struct args_size stack_args_size; + tree function_result_decl; + tree orig_fnargs; + rtx first_conversion_insn; + rtx last_conversion_insn; + HOST_WIDE_INT pretend_args_size; + HOST_WIDE_INT extra_pretend_bytes; + int reg_parm_stack_space; +}; + +struct assign_parm_data_one +{ + tree nominal_type; + tree passed_type; + rtx entry_parm; + rtx stack_parm; + enum machine_mode nominal_mode; + enum machine_mode passed_mode; + enum machine_mode promoted_mode; + struct locate_and_pad_arg_data locate; + int partial; + BOOL_BITFIELD named_arg : 1; + BOOL_BITFIELD passed_pointer : 1; + BOOL_BITFIELD on_stack : 1; + BOOL_BITFIELD loaded_in_reg : 1; +}; + +/* A subroutine of assign_parms. Initialize ALL. */ + +static void +assign_parms_initialize_all (struct assign_parm_data_all *all) +{ + tree fntype; + + memset (all, 0, sizeof (*all)); + + fntype = TREE_TYPE (current_function_decl); + +#ifdef INIT_CUMULATIVE_INCOMING_ARGS + INIT_CUMULATIVE_INCOMING_ARGS (all->args_so_far, fntype, NULL_RTX); +#else + INIT_CUMULATIVE_ARGS (all->args_so_far, fntype, NULL_RTX, + current_function_decl, -1); +#endif + +#ifdef REG_PARM_STACK_SPACE + all->reg_parm_stack_space = REG_PARM_STACK_SPACE (current_function_decl); +#endif +} + +/* If ARGS contains entries with complex types, split the entry into two + entries of the component type. Return a new list of substitutions are + needed, else the old list. */ + +static tree +split_complex_args (tree args) +{ + tree p; + + /* Before allocating memory, check for the common case of no complex. */ + for (p = args; p; p = TREE_CHAIN (p)) + { + tree type = TREE_TYPE (p); + if (TREE_CODE (type) == COMPLEX_TYPE + && targetm.calls.split_complex_arg (type)) + goto found; + } + return args; + + found: + args = copy_list (args); + + for (p = args; p; p = TREE_CHAIN (p)) + { + tree type = TREE_TYPE (p); + if (TREE_CODE (type) == COMPLEX_TYPE + && targetm.calls.split_complex_arg (type)) + { + tree decl; + tree subtype = TREE_TYPE (type); + bool addressable = TREE_ADDRESSABLE (p); + + /* Rewrite the PARM_DECL's type with its component. */ + TREE_TYPE (p) = subtype; + DECL_ARG_TYPE (p) = TREE_TYPE (DECL_ARG_TYPE (p)); + DECL_MODE (p) = VOIDmode; + DECL_SIZE (p) = NULL; + DECL_SIZE_UNIT (p) = NULL; + /* If this arg must go in memory, put it in a pseudo here. + We can't allow it to go in memory as per normal parms, + because the usual place might not have the imag part + adjacent to the real part. */ + DECL_ARTIFICIAL (p) = addressable; + DECL_IGNORED_P (p) = addressable; + TREE_ADDRESSABLE (p) = 0; + layout_decl (p, 0); + + /* Build a second synthetic decl. */ + decl = build_decl (PARM_DECL, NULL_TREE, subtype); + DECL_ARG_TYPE (decl) = DECL_ARG_TYPE (p); + DECL_ARTIFICIAL (decl) = addressable; + DECL_IGNORED_P (decl) = addressable; + layout_decl (decl, 0); + + /* Splice it in; skip the new decl. */ + TREE_CHAIN (decl) = TREE_CHAIN (p); + TREE_CHAIN (p) = decl; + p = decl; + } + } + + return args; +} + +/* A subroutine of assign_parms. Adjust the parameter list to incorporate + the hidden struct return argument, and (abi willing) complex args. + Return the new parameter list. */ + +static tree +assign_parms_augmented_arg_list (struct assign_parm_data_all *all) +{ + tree fndecl = current_function_decl; + tree fntype = TREE_TYPE (fndecl); + tree fnargs = DECL_ARGUMENTS (fndecl); + + /* If struct value address is treated as the first argument, make it so. */ + if (aggregate_value_p (DECL_RESULT (fndecl), fndecl) + && ! cfun->returns_pcc_struct + && targetm.calls.struct_value_rtx (TREE_TYPE (fndecl), 1) == 0) + { + tree type = build_pointer_type (TREE_TYPE (fntype)); + tree decl; + + decl = build_decl (PARM_DECL, NULL_TREE, type); + DECL_ARG_TYPE (decl) = type; + DECL_ARTIFICIAL (decl) = 1; + DECL_IGNORED_P (decl) = 1; + + TREE_CHAIN (decl) = fnargs; + fnargs = decl; + all->function_result_decl = decl; + } + + all->orig_fnargs = fnargs; + + /* If the target wants to split complex arguments into scalars, do so. */ + if (targetm.calls.split_complex_arg) + fnargs = split_complex_args (fnargs); + + return fnargs; +} + +/* A subroutine of assign_parms. Examine PARM and pull out type and mode + data for the parameter. Incorporate ABI specifics such as pass-by- + reference and type promotion. */ + +static void +assign_parm_find_data_types (struct assign_parm_data_all *all, tree parm, + struct assign_parm_data_one *data) +{ + tree nominal_type, passed_type; + enum machine_mode nominal_mode, passed_mode, promoted_mode; + + memset (data, 0, sizeof (*data)); + + /* NAMED_ARG is a misnomer. We really mean 'non-variadic'. */ + if (!cfun->stdarg) + data->named_arg = 1; /* No variadic parms. */ + else if (TREE_CHAIN (parm)) + data->named_arg = 1; /* Not the last non-variadic parm. */ + else if (targetm.calls.strict_argument_naming (&all->args_so_far)) + data->named_arg = 1; /* Only variadic ones are unnamed. */ + else + data->named_arg = 0; /* Treat as variadic. */ + + nominal_type = TREE_TYPE (parm); + passed_type = DECL_ARG_TYPE (parm); + + /* Look out for errors propagating this far. Also, if the parameter's + type is void then its value doesn't matter. */ + if (TREE_TYPE (parm) == error_mark_node + /* This can happen after weird syntax errors + or if an enum type is defined among the parms. */ + || TREE_CODE (parm) != PARM_DECL + || passed_type == NULL + || VOID_TYPE_P (nominal_type)) + { + nominal_type = passed_type = void_type_node; + nominal_mode = passed_mode = promoted_mode = VOIDmode; + goto egress; + } + + /* Find mode of arg as it is passed, and mode of arg as it should be + during execution of this function. */ + passed_mode = TYPE_MODE (passed_type); + nominal_mode = TYPE_MODE (nominal_type); + + /* If the parm is to be passed as a transparent union, use the type of + the first field for the tests below. We have already verified that + the modes are the same. */ + if (TREE_CODE (passed_type) == UNION_TYPE + && TYPE_TRANSPARENT_UNION (passed_type)) + passed_type = TREE_TYPE (TYPE_FIELDS (passed_type)); + + /* See if this arg was passed by invisible reference. */ + if (pass_by_reference (&all->args_so_far, passed_mode, + passed_type, data->named_arg)) + { + passed_type = nominal_type = build_pointer_type (passed_type); + data->passed_pointer = true; + passed_mode = nominal_mode = Pmode; + } + + /* Find mode as it is passed by the ABI. */ + promoted_mode = passed_mode; + if (targetm.calls.promote_function_args (TREE_TYPE (current_function_decl))) + { + int unsignedp = TYPE_UNSIGNED (passed_type); + promoted_mode = promote_mode (passed_type, promoted_mode, + &unsignedp, 1); + } + + egress: + data->nominal_type = nominal_type; + data->passed_type = passed_type; + data->nominal_mode = nominal_mode; + data->passed_mode = passed_mode; + data->promoted_mode = promoted_mode; +} + +/* A subroutine of assign_parms. Invoke setup_incoming_varargs. */ + +static void +assign_parms_setup_varargs (struct assign_parm_data_all *all, + struct assign_parm_data_one *data, bool no_rtl) +{ + int varargs_pretend_bytes = 0; + + targetm.calls.setup_incoming_varargs (&all->args_so_far, + data->promoted_mode, + data->passed_type, + &varargs_pretend_bytes, no_rtl); + + /* If the back-end has requested extra stack space, record how much is + needed. Do not change pretend_args_size otherwise since it may be + nonzero from an earlier partial argument. */ + if (varargs_pretend_bytes > 0) + all->pretend_args_size = varargs_pretend_bytes; +} + +/* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to + the incoming location of the current parameter. */ + +static void +assign_parm_find_entry_rtl (struct assign_parm_data_all *all, + struct assign_parm_data_one *data) +{ + HOST_WIDE_INT pretend_bytes = 0; + rtx entry_parm; + bool in_regs; + + if (data->promoted_mode == VOIDmode) + { + data->entry_parm = data->stack_parm = const0_rtx; + return; + } + +#ifdef FUNCTION_INCOMING_ARG + entry_parm = FUNCTION_INCOMING_ARG (all->args_so_far, data->promoted_mode, + data->passed_type, data->named_arg); +#else + entry_parm = FUNCTION_ARG (all->args_so_far, data->promoted_mode, + data->passed_type, data->named_arg); +#endif + + if (entry_parm == 0) + data->promoted_mode = data->passed_mode; + + /* Determine parm's home in the stack, in case it arrives in the stack + or we should pretend it did. Compute the stack position and rtx where + the argument arrives and its size. + + There is one complexity here: If this was a parameter that would + have been passed in registers, but wasn't only because it is + __builtin_va_alist, we want locate_and_pad_parm to treat it as if + it came in a register so that REG_PARM_STACK_SPACE isn't skipped. + In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0 + as it was the previous time. */ + in_regs = entry_parm != 0; +#ifdef STACK_PARMS_IN_REG_PARM_AREA + in_regs = true; +#endif + if (!in_regs && !data->named_arg) + { + if (targetm.calls.pretend_outgoing_varargs_named (&all->args_so_far)) + { + rtx tem; +#ifdef FUNCTION_INCOMING_ARG + tem = FUNCTION_INCOMING_ARG (all->args_so_far, data->promoted_mode, + data->passed_type, true); +#else + tem = FUNCTION_ARG (all->args_so_far, data->promoted_mode, + data->passed_type, true); +#endif + in_regs = tem != NULL; + } + } + + /* If this parameter was passed both in registers and in the stack, use + the copy on the stack. */ + if (targetm.calls.must_pass_in_stack (data->promoted_mode, + data->passed_type)) + entry_parm = 0; + + if (entry_parm) + { + int partial; + + partial = targetm.calls.arg_partial_bytes (&all->args_so_far, + data->promoted_mode, + data->passed_type, + data->named_arg); + data->partial = partial; + + /* The caller might already have allocated stack space for the + register parameters. */ + if (partial != 0 && all->reg_parm_stack_space == 0) + { + /* Part of this argument is passed in registers and part + is passed on the stack. Ask the prologue code to extend + the stack part so that we can recreate the full value. + + PRETEND_BYTES is the size of the registers we need to store. + CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra + stack space that the prologue should allocate. + + Internally, gcc assumes that the argument pointer is aligned + to STACK_BOUNDARY bits. This is used both for alignment + optimizations (see init_emit) and to locate arguments that are + aligned to more than PARM_BOUNDARY bits. We must preserve this + invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to + a stack boundary. */ + + /* We assume at most one partial arg, and it must be the first + argument on the stack. */ + gcc_assert (!all->extra_pretend_bytes && !all->pretend_args_size); + + pretend_bytes = partial; + all->pretend_args_size = CEIL_ROUND (pretend_bytes, STACK_BYTES); + + /* We want to align relative to the actual stack pointer, so + don't include this in the stack size until later. */ + all->extra_pretend_bytes = all->pretend_args_size; + } + } + + locate_and_pad_parm (data->promoted_mode, data->passed_type, in_regs, + entry_parm ? data->partial : 0, current_function_decl, + &all->stack_args_size, &data->locate); + + /* Update parm_stack_boundary if this parameter is passed in the + stack. */ + if (!in_regs && crtl->parm_stack_boundary < data->locate.boundary) + crtl->parm_stack_boundary = data->locate.boundary; + + /* Adjust offsets to include the pretend args. */ + pretend_bytes = all->extra_pretend_bytes - pretend_bytes; + data->locate.slot_offset.constant += pretend_bytes; + data->locate.offset.constant += pretend_bytes; + + data->entry_parm = entry_parm; +} + +/* A subroutine of assign_parms. If there is actually space on the stack + for this parm, count it in stack_args_size and return true. */ + +static bool +assign_parm_is_stack_parm (struct assign_parm_data_all *all, + struct assign_parm_data_one *data) +{ + /* Trivially true if we've no incoming register. */ + if (data->entry_parm == NULL) + ; + /* Also true if we're partially in registers and partially not, + since we've arranged to drop the entire argument on the stack. */ + else if (data->partial != 0) + ; + /* Also true if the target says that it's passed in both registers + and on the stack. */ + else if (GET_CODE (data->entry_parm) == PARALLEL + && XEXP (XVECEXP (data->entry_parm, 0, 0), 0) == NULL_RTX) + ; + /* Also true if the target says that there's stack allocated for + all register parameters. */ + else if (all->reg_parm_stack_space > 0) + ; + /* Otherwise, no, this parameter has no ABI defined stack slot. */ + else + return false; + + all->stack_args_size.constant += data->locate.size.constant; + if (data->locate.size.var) + ADD_PARM_SIZE (all->stack_args_size, data->locate.size.var); + + return true; +} + +/* A subroutine of assign_parms. Given that this parameter is allocated + stack space by the ABI, find it. */ + +static void +assign_parm_find_stack_rtl (tree parm, struct assign_parm_data_one *data) +{ + rtx offset_rtx, stack_parm; + unsigned int align, boundary; + + /* If we're passing this arg using a reg, make its stack home the + aligned stack slot. */ + if (data->entry_parm) + offset_rtx = ARGS_SIZE_RTX (data->locate.slot_offset); + else + offset_rtx = ARGS_SIZE_RTX (data->locate.offset); + + stack_parm = crtl->args.internal_arg_pointer; + if (offset_rtx != const0_rtx) + stack_parm = gen_rtx_PLUS (Pmode, stack_parm, offset_rtx); + stack_parm = gen_rtx_MEM (data->promoted_mode, stack_parm); + + set_mem_attributes (stack_parm, parm, 1); + /* set_mem_attributes could set MEM_SIZE to the passed mode's size, + while promoted mode's size is needed. */ + if (data->promoted_mode != BLKmode + && data->promoted_mode != DECL_MODE (parm)) + { + set_mem_size (stack_parm, GEN_INT (GET_MODE_SIZE (data->promoted_mode))); + if (MEM_EXPR (stack_parm) && MEM_OFFSET (stack_parm)) + { + int offset = subreg_lowpart_offset (DECL_MODE (parm), + data->promoted_mode); + if (offset) + set_mem_offset (stack_parm, + plus_constant (MEM_OFFSET (stack_parm), -offset)); + } + } + + boundary = data->locate.boundary; + align = BITS_PER_UNIT; + + /* If we're padding upward, we know that the alignment of the slot + is FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're + intentionally forcing upward padding. Otherwise we have to come + up with a guess at the alignment based on OFFSET_RTX. */ + if (data->locate.where_pad != downward || data->entry_parm) + align = boundary; + else if (GET_CODE (offset_rtx) == CONST_INT) + { + align = INTVAL (offset_rtx) * BITS_PER_UNIT | boundary; + align = align & -align; + } + set_mem_align (stack_parm, align); + + if (data->entry_parm) + set_reg_attrs_for_parm (data->entry_parm, stack_parm); + + data->stack_parm = stack_parm; +} + +/* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's + always valid and contiguous. */ + +static void +assign_parm_adjust_entry_rtl (struct assign_parm_data_one *data) +{ + rtx entry_parm = data->entry_parm; + rtx stack_parm = data->stack_parm; + + /* If this parm was passed part in regs and part in memory, pretend it + arrived entirely in memory by pushing the register-part onto the stack. + In the special case of a DImode or DFmode that is split, we could put + it together in a pseudoreg directly, but for now that's not worth + bothering with. */ + if (data->partial != 0) + { + /* Handle calls that pass values in multiple non-contiguous + locations. The Irix 6 ABI has examples of this. */ + if (GET_CODE (entry_parm) == PARALLEL) + emit_group_store (validize_mem (stack_parm), entry_parm, + data->passed_type, + int_size_in_bytes (data->passed_type)); + else + { + gcc_assert (data->partial % UNITS_PER_WORD == 0); + move_block_from_reg (REGNO (entry_parm), validize_mem (stack_parm), + data->partial / UNITS_PER_WORD); + } + + entry_parm = stack_parm; + } + + /* If we didn't decide this parm came in a register, by default it came + on the stack. */ + else if (entry_parm == NULL) + entry_parm = stack_parm; + + /* When an argument is passed in multiple locations, we can't make use + of this information, but we can save some copying if the whole argument + is passed in a single register. */ + else if (GET_CODE (entry_parm) == PARALLEL + && data->nominal_mode != BLKmode + && data->passed_mode != BLKmode) + { + size_t i, len = XVECLEN (entry_parm, 0); + + for (i = 0; i < len; i++) + if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX + && REG_P (XEXP (XVECEXP (entry_parm, 0, i), 0)) + && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0)) + == data->passed_mode) + && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0) + { + entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0); + break; + } + } + + data->entry_parm = entry_parm; +} + +/* A subroutine of assign_parms. Reconstitute any values which were + passed in multiple registers and would fit in a single register. */ + +static void +assign_parm_remove_parallels (struct assign_parm_data_one *data) +{ + rtx entry_parm = data->entry_parm; + + /* Convert the PARALLEL to a REG of the same mode as the parallel. + This can be done with register operations rather than on the + stack, even if we will store the reconstituted parameter on the + stack later. */ + if (GET_CODE (entry_parm) == PARALLEL && GET_MODE (entry_parm) != BLKmode) + { + rtx parmreg = gen_reg_rtx (GET_MODE (entry_parm)); + emit_group_store (parmreg, entry_parm, data->passed_type, + GET_MODE_SIZE (GET_MODE (entry_parm))); + entry_parm = parmreg; + } + + data->entry_parm = entry_parm; +} + +/* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's + always valid and properly aligned. */ + +static void +assign_parm_adjust_stack_rtl (struct assign_parm_data_one *data) +{ + rtx stack_parm = data->stack_parm; + + /* If we can't trust the parm stack slot to be aligned enough for its + ultimate type, don't use that slot after entry. We'll make another + stack slot, if we need one. */ + if (stack_parm + && ((STRICT_ALIGNMENT + && GET_MODE_ALIGNMENT (data->nominal_mode) > MEM_ALIGN (stack_parm)) + || (data->nominal_type + && TYPE_ALIGN (data->nominal_type) > MEM_ALIGN (stack_parm) + && MEM_ALIGN (stack_parm) < PREFERRED_STACK_BOUNDARY))) + stack_parm = NULL; + + /* If parm was passed in memory, and we need to convert it on entry, + don't store it back in that same slot. */ + else if (data->entry_parm == stack_parm + && data->nominal_mode != BLKmode + && data->nominal_mode != data->passed_mode) + stack_parm = NULL; + + /* If stack protection is in effect for this function, don't leave any + pointers in their passed stack slots. */ + else if (crtl->stack_protect_guard + && (flag_stack_protect == 2 + || data->passed_pointer + || POINTER_TYPE_P (data->nominal_type))) + stack_parm = NULL; + + data->stack_parm = stack_parm; +} + +/* A subroutine of assign_parms. Return true if the current parameter + should be stored as a BLKmode in the current frame. */ + +static bool +assign_parm_setup_block_p (struct assign_parm_data_one *data) +{ + if (data->nominal_mode == BLKmode) + return true; + if (GET_MODE (data->entry_parm) == BLKmode) + return true; + +#ifdef BLOCK_REG_PADDING + /* Only assign_parm_setup_block knows how to deal with register arguments + that are padded at the least significant end. */ + if (REG_P (data->entry_parm) + && GET_MODE_SIZE (data->promoted_mode) < UNITS_PER_WORD + && (BLOCK_REG_PADDING (data->passed_mode, data->passed_type, 1) + == (BYTES_BIG_ENDIAN ? upward : downward))) + return true; +#endif + + return false; +} + +/* A subroutine of assign_parms. Arrange for the parameter to be + present and valid in DATA->STACK_RTL. */ + +static void +assign_parm_setup_block (struct assign_parm_data_all *all, + tree parm, struct assign_parm_data_one *data) +{ + rtx entry_parm = data->entry_parm; + rtx stack_parm = data->stack_parm; + HOST_WIDE_INT size; + HOST_WIDE_INT size_stored; + + if (GET_CODE (entry_parm) == PARALLEL) + entry_parm = emit_group_move_into_temps (entry_parm); + + size = int_size_in_bytes (data->passed_type); + size_stored = CEIL_ROUND (size, UNITS_PER_WORD); + if (stack_parm == 0) + { + DECL_ALIGN (parm) = MAX (DECL_ALIGN (parm), BITS_PER_WORD); + stack_parm = assign_stack_local (BLKmode, size_stored, + DECL_ALIGN (parm)); + if (GET_MODE_SIZE (GET_MODE (entry_parm)) == size) + PUT_MODE (stack_parm, GET_MODE (entry_parm)); + set_mem_attributes (stack_parm, parm, 1); + } + + /* If a BLKmode arrives in registers, copy it to a stack slot. Handle + calls that pass values in multiple non-contiguous locations. */ + if (REG_P (entry_parm) || GET_CODE (entry_parm) == PARALLEL) + { + rtx mem; + + /* Note that we will be storing an integral number of words. + So we have to be careful to ensure that we allocate an + integral number of words. We do this above when we call + assign_stack_local if space was not allocated in the argument + list. If it was, this will not work if PARM_BOUNDARY is not + a multiple of BITS_PER_WORD. It isn't clear how to fix this + if it becomes a problem. Exception is when BLKmode arrives + with arguments not conforming to word_mode. */ + + if (data->stack_parm == 0) + ; + else if (GET_CODE (entry_parm) == PARALLEL) + ; + else + gcc_assert (!size || !(PARM_BOUNDARY % BITS_PER_WORD)); + + mem = validize_mem (stack_parm); + + /* Handle values in multiple non-contiguous locations. */ + if (GET_CODE (entry_parm) == PARALLEL) + { + push_to_sequence2 (all->first_conversion_insn, + all->last_conversion_insn); + emit_group_store (mem, entry_parm, data->passed_type, size); + all->first_conversion_insn = get_insns (); + all->last_conversion_insn = get_last_insn (); + end_sequence (); + } + + else if (size == 0) + ; + + /* If SIZE is that of a mode no bigger than a word, just use + that mode's store operation. */ + else if (size <= UNITS_PER_WORD) + { + enum machine_mode mode + = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0); + + if (mode != BLKmode +#ifdef BLOCK_REG_PADDING + && (size == UNITS_PER_WORD + || (BLOCK_REG_PADDING (mode, data->passed_type, 1) + != (BYTES_BIG_ENDIAN ? upward : downward))) +#endif + ) + { + rtx reg; + + /* We are really truncating a word_mode value containing + SIZE bytes into a value of mode MODE. If such an + operation requires no actual instructions, we can refer + to the value directly in mode MODE, otherwise we must + start with the register in word_mode and explicitly + convert it. */ + if (TRULY_NOOP_TRUNCATION (size * BITS_PER_UNIT, BITS_PER_WORD)) + reg = gen_rtx_REG (mode, REGNO (entry_parm)); + else + { + reg = gen_rtx_REG (word_mode, REGNO (entry_parm)); + reg = convert_to_mode (mode, copy_to_reg (reg), 1); + } + emit_move_insn (change_address (mem, mode, 0), reg); + } + + /* Blocks smaller than a word on a BYTES_BIG_ENDIAN + machine must be aligned to the left before storing + to memory. Note that the previous test doesn't + handle all cases (e.g. SIZE == 3). */ + else if (size != UNITS_PER_WORD +#ifdef BLOCK_REG_PADDING + && (BLOCK_REG_PADDING (mode, data->passed_type, 1) + == downward) +#else + && BYTES_BIG_ENDIAN +#endif + ) + { + rtx tem, x; + int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT; + rtx reg = gen_rtx_REG (word_mode, REGNO (entry_parm)); + + x = expand_shift (LSHIFT_EXPR, word_mode, reg, + build_int_cst (NULL_TREE, by), + NULL_RTX, 1); + tem = change_address (mem, word_mode, 0); + emit_move_insn (tem, x); + } + else + move_block_from_reg (REGNO (entry_parm), mem, + size_stored / UNITS_PER_WORD); + } + else + move_block_from_reg (REGNO (entry_parm), mem, + size_stored / UNITS_PER_WORD); + } + else if (data->stack_parm == 0) + { + push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn); + emit_block_move (stack_parm, data->entry_parm, GEN_INT (size), + BLOCK_OP_NORMAL); + all->first_conversion_insn = get_insns (); + all->last_conversion_insn = get_last_insn (); + end_sequence (); + } + + data->stack_parm = stack_parm; + SET_DECL_RTL (parm, stack_parm); +} + +/* A subroutine of assign_parms. Allocate a pseudo to hold the current + parameter. Get it there. Perform all ABI specified conversions. */ + +static void +assign_parm_setup_reg (struct assign_parm_data_all *all, tree parm, + struct assign_parm_data_one *data) +{ + rtx parmreg; + enum machine_mode promoted_nominal_mode; + int unsignedp = TYPE_UNSIGNED (TREE_TYPE (parm)); + bool did_conversion = false; + + /* Store the parm in a pseudoregister during the function, but we may + need to do it in a wider mode. */ + + /* This is not really promoting for a call. However we need to be + consistent with assign_parm_find_data_types and expand_expr_real_1. */ + promoted_nominal_mode + = promote_mode (data->nominal_type, data->nominal_mode, &unsignedp, 1); + + parmreg = gen_reg_rtx (promoted_nominal_mode); + + if (!DECL_ARTIFICIAL (parm)) + mark_user_reg (parmreg); + + /* If this was an item that we received a pointer to, + set DECL_RTL appropriately. */ + if (data->passed_pointer) + { + rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data->passed_type)), parmreg); + set_mem_attributes (x, parm, 1); + SET_DECL_RTL (parm, x); + } + else + SET_DECL_RTL (parm, parmreg); + + assign_parm_remove_parallels (data); + + /* Copy the value into the register. */ + if (data->nominal_mode != data->passed_mode + || promoted_nominal_mode != data->promoted_mode) + { + int save_tree_used; + + /* ENTRY_PARM has been converted to PROMOTED_MODE, its + mode, by the caller. We now have to convert it to + NOMINAL_MODE, if different. However, PARMREG may be in + a different mode than NOMINAL_MODE if it is being stored + promoted. + + If ENTRY_PARM is a hard register, it might be in a register + not valid for operating in its mode (e.g., an odd-numbered + register for a DFmode). In that case, moves are the only + thing valid, so we can't do a convert from there. This + occurs when the calling sequence allow such misaligned + usages. + + In addition, the conversion may involve a call, which could + clobber parameters which haven't been copied to pseudo + registers yet. Therefore, we must first copy the parm to + a pseudo reg here, and save the conversion until after all + parameters have been moved. */ + + rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm)); + + emit_move_insn (tempreg, validize_mem (data->entry_parm)); + + push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn); + tempreg = convert_to_mode (data->nominal_mode, tempreg, unsignedp); + + if (GET_CODE (tempreg) == SUBREG + && GET_MODE (tempreg) == data->nominal_mode + && REG_P (SUBREG_REG (tempreg)) + && data->nominal_mode == data->passed_mode + && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (data->entry_parm) + && GET_MODE_SIZE (GET_MODE (tempreg)) + < GET_MODE_SIZE (GET_MODE (data->entry_parm))) + { + /* The argument is already sign/zero extended, so note it + into the subreg. */ + SUBREG_PROMOTED_VAR_P (tempreg) = 1; + SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp); + } + + /* TREE_USED gets set erroneously during expand_assignment. */ + save_tree_used = TREE_USED (parm); + expand_assignment (parm, make_tree (data->nominal_type, tempreg), false); + TREE_USED (parm) = save_tree_used; + all->first_conversion_insn = get_insns (); + all->last_conversion_insn = get_last_insn (); + end_sequence (); + + did_conversion = true; + } + else + emit_move_insn (parmreg, validize_mem (data->entry_parm)); + + /* If we were passed a pointer but the actual value can safely live + in a register, put it in one. */ + if (data->passed_pointer + && TYPE_MODE (TREE_TYPE (parm)) != BLKmode + /* If by-reference argument was promoted, demote it. */ + && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm)) + || use_register_for_decl (parm))) + { + /* We can't use nominal_mode, because it will have been set to + Pmode above. We must use the actual mode of the parm. */ + parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm))); + mark_user_reg (parmreg); + + if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm))) + { + rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm))); + int unsigned_p = TYPE_UNSIGNED (TREE_TYPE (parm)); + + push_to_sequence2 (all->first_conversion_insn, + all->last_conversion_insn); + emit_move_insn (tempreg, DECL_RTL (parm)); + tempreg = convert_to_mode (GET_MODE (parmreg), tempreg, unsigned_p); + emit_move_insn (parmreg, tempreg); + all->first_conversion_insn = get_insns (); + all->last_conversion_insn = get_last_insn (); + end_sequence (); + + did_conversion = true; + } + else + emit_move_insn (parmreg, DECL_RTL (parm)); + + SET_DECL_RTL (parm, parmreg); + + /* STACK_PARM is the pointer, not the parm, and PARMREG is + now the parm. */ + data->stack_parm = NULL; + } + + /* Mark the register as eliminable if we did no conversion and it was + copied from memory at a fixed offset, and the arg pointer was not + copied to a pseudo-reg. If the arg pointer is a pseudo reg or the + offset formed an invalid address, such memory-equivalences as we + make here would screw up life analysis for it. */ + if (data->nominal_mode == data->passed_mode + && !did_conversion + && data->stack_parm != 0 + && MEM_P (data->stack_parm) + && data->locate.offset.var == 0 + && reg_mentioned_p (virtual_incoming_args_rtx, + XEXP (data->stack_parm, 0))) + { + rtx linsn = get_last_insn (); + rtx sinsn, set; + + /* Mark complex types separately. */ + if (GET_CODE (parmreg) == CONCAT) + { + enum machine_mode submode + = GET_MODE_INNER (GET_MODE (parmreg)); + int regnor = REGNO (XEXP (parmreg, 0)); + int regnoi = REGNO (XEXP (parmreg, 1)); + rtx stackr = adjust_address_nv (data->stack_parm, submode, 0); + rtx stacki = adjust_address_nv (data->stack_parm, submode, + GET_MODE_SIZE (submode)); + + /* Scan backwards for the set of the real and + imaginary parts. */ + for (sinsn = linsn; sinsn != 0; + sinsn = prev_nonnote_insn (sinsn)) + { + set = single_set (sinsn); + if (set == 0) + continue; + + if (SET_DEST (set) == regno_reg_rtx [regnoi]) + set_unique_reg_note (sinsn, REG_EQUIV, stacki); + else if (SET_DEST (set) == regno_reg_rtx [regnor]) + set_unique_reg_note (sinsn, REG_EQUIV, stackr); + } + } + else if ((set = single_set (linsn)) != 0 + && SET_DEST (set) == parmreg) + set_unique_reg_note (linsn, REG_EQUIV, data->stack_parm); + } + + /* For pointer data type, suggest pointer register. */ + if (POINTER_TYPE_P (TREE_TYPE (parm))) + mark_reg_pointer (parmreg, + TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm)))); +} + +/* A subroutine of assign_parms. Allocate stack space to hold the current + parameter. Get it there. Perform all ABI specified conversions. */ + +static void +assign_parm_setup_stack (struct assign_parm_data_all *all, tree parm, + struct assign_parm_data_one *data) +{ + /* Value must be stored in the stack slot STACK_PARM during function + execution. */ + bool to_conversion = false; + + assign_parm_remove_parallels (data); + + if (data->promoted_mode != data->nominal_mode) + { + /* Conversion is required. */ + rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm)); + + emit_move_insn (tempreg, validize_mem (data->entry_parm)); + + push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn); + to_conversion = true; + + data->entry_parm = convert_to_mode (data->nominal_mode, tempreg, + TYPE_UNSIGNED (TREE_TYPE (parm))); + + if (data->stack_parm) + /* ??? This may need a big-endian conversion on sparc64. */ + data->stack_parm + = adjust_address (data->stack_parm, data->nominal_mode, 0); + } + + if (data->entry_parm != data->stack_parm) + { + rtx src, dest; + + if (data->stack_parm == 0) + { + int align = STACK_SLOT_ALIGNMENT (data->passed_type, + GET_MODE (data->entry_parm), + TYPE_ALIGN (data->passed_type)); + data->stack_parm + = assign_stack_local (GET_MODE (data->entry_parm), + GET_MODE_SIZE (GET_MODE (data->entry_parm)), + align); + set_mem_attributes (data->stack_parm, parm, 1); + } + + dest = validize_mem (data->stack_parm); + src = validize_mem (data->entry_parm); + + if (MEM_P (src)) + { + /* Use a block move to handle potentially misaligned entry_parm. */ + if (!to_conversion) + push_to_sequence2 (all->first_conversion_insn, + all->last_conversion_insn); + to_conversion = true; + + emit_block_move (dest, src, + GEN_INT (int_size_in_bytes (data->passed_type)), + BLOCK_OP_NORMAL); + } + else + emit_move_insn (dest, src); + } + + if (to_conversion) + { + all->first_conversion_insn = get_insns (); + all->last_conversion_insn = get_last_insn (); + end_sequence (); + } + + SET_DECL_RTL (parm, data->stack_parm); +} + +/* A subroutine of assign_parms. If the ABI splits complex arguments, then + undo the frobbing that we did in assign_parms_augmented_arg_list. */ + +static void +assign_parms_unsplit_complex (struct assign_parm_data_all *all, tree fnargs) +{ + tree parm; + tree orig_fnargs = all->orig_fnargs; + + for (parm = orig_fnargs; parm; parm = TREE_CHAIN (parm)) + { + if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE + && targetm.calls.split_complex_arg (TREE_TYPE (parm))) + { + rtx tmp, real, imag; + enum machine_mode inner = GET_MODE_INNER (DECL_MODE (parm)); + + real = DECL_RTL (fnargs); + imag = DECL_RTL (TREE_CHAIN (fnargs)); + if (inner != GET_MODE (real)) + { + real = gen_lowpart_SUBREG (inner, real); + imag = gen_lowpart_SUBREG (inner, imag); + } + + if (TREE_ADDRESSABLE (parm)) + { + rtx rmem, imem; + HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (parm)); + int align = STACK_SLOT_ALIGNMENT (TREE_TYPE (parm), + DECL_MODE (parm), + TYPE_ALIGN (TREE_TYPE (parm))); + + /* split_complex_arg put the real and imag parts in + pseudos. Move them to memory. */ + tmp = assign_stack_local (DECL_MODE (parm), size, align); + set_mem_attributes (tmp, parm, 1); + rmem = adjust_address_nv (tmp, inner, 0); + imem = adjust_address_nv (tmp, inner, GET_MODE_SIZE (inner)); + push_to_sequence2 (all->first_conversion_insn, + all->last_conversion_insn); + emit_move_insn (rmem, real); + emit_move_insn (imem, imag); + all->first_conversion_insn = get_insns (); + all->last_conversion_insn = get_last_insn (); + end_sequence (); + } + else + tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag); + SET_DECL_RTL (parm, tmp); + + real = DECL_INCOMING_RTL (fnargs); + imag = DECL_INCOMING_RTL (TREE_CHAIN (fnargs)); + if (inner != GET_MODE (real)) + { + real = gen_lowpart_SUBREG (inner, real); + imag = gen_lowpart_SUBREG (inner, imag); + } + tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag); + set_decl_incoming_rtl (parm, tmp, false); + fnargs = TREE_CHAIN (fnargs); + } + else + { + SET_DECL_RTL (parm, DECL_RTL (fnargs)); + set_decl_incoming_rtl (parm, DECL_INCOMING_RTL (fnargs), false); + + /* Set MEM_EXPR to the original decl, i.e. to PARM, + instead of the copy of decl, i.e. FNARGS. */ + if (DECL_INCOMING_RTL (parm) && MEM_P (DECL_INCOMING_RTL (parm))) + set_mem_expr (DECL_INCOMING_RTL (parm), parm); + } + + fnargs = TREE_CHAIN (fnargs); + } +} + +/* Assign RTL expressions to the function's parameters. This may involve + copying them into registers and using those registers as the DECL_RTL. */ + +static void +assign_parms (tree fndecl) +{ + struct assign_parm_data_all all; + tree fnargs, parm; + + crtl->args.internal_arg_pointer + = targetm.calls.internal_arg_pointer (); + + assign_parms_initialize_all (&all); + fnargs = assign_parms_augmented_arg_list (&all); + + for (parm = fnargs; parm; parm = TREE_CHAIN (parm)) + { + struct assign_parm_data_one data; + + /* Extract the type of PARM; adjust it according to ABI. */ + assign_parm_find_data_types (&all, parm, &data); + + /* Early out for errors and void parameters. */ + if (data.passed_mode == VOIDmode) + { + SET_DECL_RTL (parm, const0_rtx); + DECL_INCOMING_RTL (parm) = DECL_RTL (parm); + continue; + } + + /* Estimate stack alignment from parameter alignment. */ + if (SUPPORTS_STACK_ALIGNMENT) + { + unsigned int align = FUNCTION_ARG_BOUNDARY (data.promoted_mode, + data.passed_type); + if (TYPE_ALIGN (data.nominal_type) > align) + align = TYPE_ALIGN (data.passed_type); + if (crtl->stack_alignment_estimated < align) + { + gcc_assert (!crtl->stack_realign_processed); + crtl->stack_alignment_estimated = align; + } + } + + if (cfun->stdarg && !TREE_CHAIN (parm)) + assign_parms_setup_varargs (&all, &data, false); + + /* Find out where the parameter arrives in this function. */ + assign_parm_find_entry_rtl (&all, &data); + + /* Find out where stack space for this parameter might be. */ + if (assign_parm_is_stack_parm (&all, &data)) + { + assign_parm_find_stack_rtl (parm, &data); + assign_parm_adjust_entry_rtl (&data); + } + + /* Record permanently how this parm was passed. */ + set_decl_incoming_rtl (parm, data.entry_parm, data.passed_pointer); + + /* Update info on where next arg arrives in registers. */ + FUNCTION_ARG_ADVANCE (all.args_so_far, data.promoted_mode, + data.passed_type, data.named_arg); + + assign_parm_adjust_stack_rtl (&data); + + if (assign_parm_setup_block_p (&data)) + assign_parm_setup_block (&all, parm, &data); + else if (data.passed_pointer || use_register_for_decl (parm)) + assign_parm_setup_reg (&all, parm, &data); + else + assign_parm_setup_stack (&all, parm, &data); + } + + if (targetm.calls.split_complex_arg && fnargs != all.orig_fnargs) + assign_parms_unsplit_complex (&all, fnargs); + + /* Output all parameter conversion instructions (possibly including calls) + now that all parameters have been copied out of hard registers. */ + emit_insn (all.first_conversion_insn); + + /* Estimate reload stack alignment from scalar return mode. */ + if (SUPPORTS_STACK_ALIGNMENT) + { + if (DECL_RESULT (fndecl)) + { + tree type = TREE_TYPE (DECL_RESULT (fndecl)); + enum machine_mode mode = TYPE_MODE (type); + + if (mode != BLKmode + && mode != VOIDmode + && !AGGREGATE_TYPE_P (type)) + { + unsigned int align = GET_MODE_ALIGNMENT (mode); + if (crtl->stack_alignment_estimated < align) + { + gcc_assert (!crtl->stack_realign_processed); + crtl->stack_alignment_estimated = align; + } + } + } + } + + /* If we are receiving a struct value address as the first argument, set up + the RTL for the function result. As this might require code to convert + the transmitted address to Pmode, we do this here to ensure that possible + preliminary conversions of the address have been emitted already. */ + if (all.function_result_decl) + { + tree result = DECL_RESULT (current_function_decl); + rtx addr = DECL_RTL (all.function_result_decl); + rtx x; + + if (DECL_BY_REFERENCE (result)) + x = addr; + else + { + addr = convert_memory_address (Pmode, addr); + x = gen_rtx_MEM (DECL_MODE (result), addr); + set_mem_attributes (x, result, 1); + } + SET_DECL_RTL (result, x); + } + + /* We have aligned all the args, so add space for the pretend args. */ + crtl->args.pretend_args_size = all.pretend_args_size; + all.stack_args_size.constant += all.extra_pretend_bytes; + crtl->args.size = all.stack_args_size.constant; + + /* Adjust function incoming argument size for alignment and + minimum length. */ + +#ifdef REG_PARM_STACK_SPACE + crtl->args.size = MAX (crtl->args.size, + REG_PARM_STACK_SPACE (fndecl)); +#endif + + crtl->args.size = CEIL_ROUND (crtl->args.size, + PARM_BOUNDARY / BITS_PER_UNIT); + +#ifdef ARGS_GROW_DOWNWARD + crtl->args.arg_offset_rtx + = (all.stack_args_size.var == 0 ? GEN_INT (-all.stack_args_size.constant) + : expand_expr (size_diffop (all.stack_args_size.var, + size_int (-all.stack_args_size.constant)), + NULL_RTX, VOIDmode, 0)); +#else + crtl->args.arg_offset_rtx = ARGS_SIZE_RTX (all.stack_args_size); +#endif + + /* See how many bytes, if any, of its args a function should try to pop + on return. */ + + crtl->args.pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl), + crtl->args.size); + + /* For stdarg.h function, save info about + regs and stack space used by the named args. */ + + crtl->args.info = all.args_so_far; + + /* Set the rtx used for the function return value. Put this in its + own variable so any optimizers that need this information don't have + to include tree.h. Do this here so it gets done when an inlined + function gets output. */ + + crtl->return_rtx + = (DECL_RTL_SET_P (DECL_RESULT (fndecl)) + ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX); + + /* If scalar return value was computed in a pseudo-reg, or was a named + return value that got dumped to the stack, copy that to the hard + return register. */ + if (DECL_RTL_SET_P (DECL_RESULT (fndecl))) + { + tree decl_result = DECL_RESULT (fndecl); + rtx decl_rtl = DECL_RTL (decl_result); + + if (REG_P (decl_rtl) + ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER + : DECL_REGISTER (decl_result)) + { + rtx real_decl_rtl; + + real_decl_rtl = targetm.calls.function_value (TREE_TYPE (decl_result), + fndecl, true); + REG_FUNCTION_VALUE_P (real_decl_rtl) = 1; + /* The delay slot scheduler assumes that crtl->return_rtx + holds the hard register containing the return value, not a + temporary pseudo. */ + crtl->return_rtx = real_decl_rtl; + } + } +} + +/* A subroutine of gimplify_parameters, invoked via walk_tree. + For all seen types, gimplify their sizes. */ + +static tree +gimplify_parm_type (tree *tp, int *walk_subtrees, void *data) +{ + tree t = *tp; + + *walk_subtrees = 0; + if (TYPE_P (t)) + { + if (POINTER_TYPE_P (t)) + *walk_subtrees = 1; + else if (TYPE_SIZE (t) && !TREE_CONSTANT (TYPE_SIZE (t)) + && !TYPE_SIZES_GIMPLIFIED (t)) + { + gimplify_type_sizes (t, (gimple_seq *) data); + *walk_subtrees = 1; + } + } + + return NULL; +} + +/* Gimplify the parameter list for current_function_decl. This involves + evaluating SAVE_EXPRs of variable sized parameters and generating code + to implement callee-copies reference parameters. Returns a sequence of + statements to add to the beginning of the function. */ + +gimple_seq +gimplify_parameters (void) +{ + struct assign_parm_data_all all; + tree fnargs, parm; + gimple_seq stmts = NULL; + + assign_parms_initialize_all (&all); + fnargs = assign_parms_augmented_arg_list (&all); + + for (parm = fnargs; parm; parm = TREE_CHAIN (parm)) + { + struct assign_parm_data_one data; + + /* Extract the type of PARM; adjust it according to ABI. */ + assign_parm_find_data_types (&all, parm, &data); + + /* Early out for errors and void parameters. */ + if (data.passed_mode == VOIDmode || DECL_SIZE (parm) == NULL) + continue; + + /* Update info on where next arg arrives in registers. */ + FUNCTION_ARG_ADVANCE (all.args_so_far, data.promoted_mode, + data.passed_type, data.named_arg); + + /* ??? Once upon a time variable_size stuffed parameter list + SAVE_EXPRs (amongst others) onto a pending sizes list. This + turned out to be less than manageable in the gimple world. + Now we have to hunt them down ourselves. */ + walk_tree_without_duplicates (&data.passed_type, + gimplify_parm_type, &stmts); + + if (TREE_CODE (DECL_SIZE_UNIT (parm)) != INTEGER_CST) + { + gimplify_one_sizepos (&DECL_SIZE (parm), &stmts); + gimplify_one_sizepos (&DECL_SIZE_UNIT (parm), &stmts); + } + + if (data.passed_pointer) + { + tree type = TREE_TYPE (data.passed_type); + if (reference_callee_copied (&all.args_so_far, TYPE_MODE (type), + type, data.named_arg)) + { + tree local, t; + + /* For constant-sized objects, this is trivial; for + variable-sized objects, we have to play games. */ + if (TREE_CODE (DECL_SIZE_UNIT (parm)) == INTEGER_CST + && !(flag_stack_check == GENERIC_STACK_CHECK + && compare_tree_int (DECL_SIZE_UNIT (parm), + STACK_CHECK_MAX_VAR_SIZE) > 0)) + { + local = create_tmp_var (type, get_name (parm)); + DECL_IGNORED_P (local) = 0; + /* If PARM was addressable, move that flag over + to the local copy, as its address will be taken, + not the PARMs. */ + if (TREE_ADDRESSABLE (parm)) + { + TREE_ADDRESSABLE (parm) = 0; + TREE_ADDRESSABLE (local) = 1; + } + } + else + { + tree ptr_type, addr; + + ptr_type = build_pointer_type (type); + addr = create_tmp_var (ptr_type, get_name (parm)); + DECL_IGNORED_P (addr) = 0; + local = build_fold_indirect_ref (addr); + + t = built_in_decls[BUILT_IN_ALLOCA]; + t = build_call_expr (t, 1, DECL_SIZE_UNIT (parm)); + t = fold_convert (ptr_type, t); + t = build2 (MODIFY_EXPR, TREE_TYPE (addr), addr, t); + gimplify_and_add (t, &stmts); + } + + gimplify_assign (local, parm, &stmts); + + SET_DECL_VALUE_EXPR (parm, local); + DECL_HAS_VALUE_EXPR_P (parm) = 1; + } + } + } + + return stmts; +} + +/* Compute the size and offset from the start of the stacked arguments for a + parm passed in mode PASSED_MODE and with type TYPE. + + INITIAL_OFFSET_PTR points to the current offset into the stacked + arguments. + + The starting offset and size for this parm are returned in + LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is + nonzero, the offset is that of stack slot, which is returned in + LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of + padding required from the initial offset ptr to the stack slot. + + IN_REGS is nonzero if the argument will be passed in registers. It will + never be set if REG_PARM_STACK_SPACE is not defined. + + FNDECL is the function in which the argument was defined. + + There are two types of rounding that are done. The first, controlled by + FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument + list to be aligned to the specific boundary (in bits). This rounding + affects the initial and starting offsets, but not the argument size. + + The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY, + optionally rounds the size of the parm to PARM_BOUNDARY. The + initial offset is not affected by this rounding, while the size always + is and the starting offset may be. */ + +/* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case; + INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's + callers pass in the total size of args so far as + INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */ + +void +locate_and_pad_parm (enum machine_mode passed_mode, tree type, int in_regs, + int partial, tree fndecl ATTRIBUTE_UNUSED, + struct args_size *initial_offset_ptr, + struct locate_and_pad_arg_data *locate) +{ + tree sizetree; + enum direction where_pad; + unsigned int boundary; + int reg_parm_stack_space = 0; + int part_size_in_regs; + +#ifdef REG_PARM_STACK_SPACE + reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl); + + /* If we have found a stack parm before we reach the end of the + area reserved for registers, skip that area. */ + if (! in_regs) + { + if (reg_parm_stack_space > 0) + { + if (initial_offset_ptr->var) + { + initial_offset_ptr->var + = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr), + ssize_int (reg_parm_stack_space)); + initial_offset_ptr->constant = 0; + } + else if (initial_offset_ptr->constant < reg_parm_stack_space) + initial_offset_ptr->constant = reg_parm_stack_space; + } + } +#endif /* REG_PARM_STACK_SPACE */ + + part_size_in_regs = (reg_parm_stack_space == 0 ? partial : 0); + + sizetree + = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode)); + where_pad = FUNCTION_ARG_PADDING (passed_mode, type); + boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type); + locate->where_pad = where_pad; + + /* Alignment can't exceed MAX_SUPPORTED_STACK_ALIGNMENT. */ + if (boundary > MAX_SUPPORTED_STACK_ALIGNMENT) + boundary = MAX_SUPPORTED_STACK_ALIGNMENT; + + locate->boundary = boundary; + + if (SUPPORTS_STACK_ALIGNMENT) + { + /* stack_alignment_estimated can't change after stack has been + realigned. */ + if (crtl->stack_alignment_estimated < boundary) + { + if (!crtl->stack_realign_processed) + crtl->stack_alignment_estimated = boundary; + else + { + /* If stack is realigned and stack alignment value + hasn't been finalized, it is OK not to increase + stack_alignment_estimated. The bigger alignment + requirement is recorded in stack_alignment_needed + below. */ + gcc_assert (!crtl->stack_realign_finalized + && crtl->stack_realign_needed); + } + } + } + + /* Remember if the outgoing parameter requires extra alignment on the + calling function side. */ + if (crtl->stack_alignment_needed < boundary) + crtl->stack_alignment_needed = boundary; + if (crtl->max_used_stack_slot_alignment < crtl->stack_alignment_needed) + crtl->max_used_stack_slot_alignment = crtl->stack_alignment_needed; + if (crtl->preferred_stack_boundary < boundary) + crtl->preferred_stack_boundary = boundary; + +#ifdef ARGS_GROW_DOWNWARD + locate->slot_offset.constant = -initial_offset_ptr->constant; + if (initial_offset_ptr->var) + locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0), + initial_offset_ptr->var); + + { + tree s2 = sizetree; + if (where_pad != none + && (!host_integerp (sizetree, 1) + || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY)) + s2 = round_up (s2, PARM_BOUNDARY / BITS_PER_UNIT); + SUB_PARM_SIZE (locate->slot_offset, s2); + } + + locate->slot_offset.constant += part_size_in_regs; + + if (!in_regs +#ifdef REG_PARM_STACK_SPACE + || REG_PARM_STACK_SPACE (fndecl) > 0 +#endif + ) + pad_to_arg_alignment (&locate->slot_offset, boundary, + &locate->alignment_pad); + + locate->size.constant = (-initial_offset_ptr->constant + - locate->slot_offset.constant); + if (initial_offset_ptr->var) + locate->size.var = size_binop (MINUS_EXPR, + size_binop (MINUS_EXPR, + ssize_int (0), + initial_offset_ptr->var), + locate->slot_offset.var); + + /* Pad_below needs the pre-rounded size to know how much to pad + below. */ + locate->offset = locate->slot_offset; + if (where_pad == downward) + pad_below (&locate->offset, passed_mode, sizetree); + +#else /* !ARGS_GROW_DOWNWARD */ + if (!in_regs +#ifdef REG_PARM_STACK_SPACE + || REG_PARM_STACK_SPACE (fndecl) > 0 +#endif + ) + pad_to_arg_alignment (initial_offset_ptr, boundary, + &locate->alignment_pad); + locate->slot_offset = *initial_offset_ptr; + +#ifdef PUSH_ROUNDING + if (passed_mode != BLKmode) + sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree))); +#endif + + /* Pad_below needs the pre-rounded size to know how much to pad below + so this must be done before rounding up. */ + locate->offset = locate->slot_offset; + if (where_pad == downward) + pad_below (&locate->offset, passed_mode, sizetree); + + if (where_pad != none + && (!host_integerp (sizetree, 1) + || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY)) + sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT); + + ADD_PARM_SIZE (locate->size, sizetree); + + locate->size.constant -= part_size_in_regs; +#endif /* ARGS_GROW_DOWNWARD */ + +#ifdef FUNCTION_ARG_OFFSET + locate->offset.constant += FUNCTION_ARG_OFFSET (passed_mode, type); +#endif +} + +/* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY. + BOUNDARY is measured in bits, but must be a multiple of a storage unit. */ + +static void +pad_to_arg_alignment (struct args_size *offset_ptr, int boundary, + struct args_size *alignment_pad) +{ + tree save_var = NULL_TREE; + HOST_WIDE_INT save_constant = 0; + int boundary_in_bytes = boundary / BITS_PER_UNIT; + HOST_WIDE_INT sp_offset = STACK_POINTER_OFFSET; + +#ifdef SPARC_STACK_BOUNDARY_HACK + /* ??? The SPARC port may claim a STACK_BOUNDARY higher than + the real alignment of %sp. However, when it does this, the + alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */ + if (SPARC_STACK_BOUNDARY_HACK) + sp_offset = 0; +#endif + + if (boundary > PARM_BOUNDARY) + { + save_var = offset_ptr->var; + save_constant = offset_ptr->constant; + } + + alignment_pad->var = NULL_TREE; + alignment_pad->constant = 0; + + if (boundary > BITS_PER_UNIT) + { + if (offset_ptr->var) + { + tree sp_offset_tree = ssize_int (sp_offset); + tree offset = size_binop (PLUS_EXPR, + ARGS_SIZE_TREE (*offset_ptr), + sp_offset_tree); +#ifdef ARGS_GROW_DOWNWARD + tree rounded = round_down (offset, boundary / BITS_PER_UNIT); +#else + tree rounded = round_up (offset, boundary / BITS_PER_UNIT); +#endif + + offset_ptr->var = size_binop (MINUS_EXPR, rounded, sp_offset_tree); + /* ARGS_SIZE_TREE includes constant term. */ + offset_ptr->constant = 0; + if (boundary > PARM_BOUNDARY) + alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var, + save_var); + } + else + { + offset_ptr->constant = -sp_offset + +#ifdef ARGS_GROW_DOWNWARD + FLOOR_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes); +#else + CEIL_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes); +#endif + if (boundary > PARM_BOUNDARY) + alignment_pad->constant = offset_ptr->constant - save_constant; + } + } +} + +static void +pad_below (struct args_size *offset_ptr, enum machine_mode passed_mode, tree sizetree) +{ + if (passed_mode != BLKmode) + { + if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY) + offset_ptr->constant + += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1) + / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT) + - GET_MODE_SIZE (passed_mode)); + } + else + { + if (TREE_CODE (sizetree) != INTEGER_CST + || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY) + { + /* Round the size up to multiple of PARM_BOUNDARY bits. */ + tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT); + /* Add it in. */ + ADD_PARM_SIZE (*offset_ptr, s2); + SUB_PARM_SIZE (*offset_ptr, sizetree); + } + } +} + + +/* True if register REGNO was alive at a place where `setjmp' was + called and was set more than once or is an argument. Such regs may + be clobbered by `longjmp'. */ + +static bool +regno_clobbered_at_setjmp (bitmap setjmp_crosses, int regno) +{ + /* There appear to be cases where some local vars never reach the + backend but have bogus regnos. */ + if (regno >= max_reg_num ()) + return false; + + return ((REG_N_SETS (regno) > 1 + || REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR), regno)) + && REGNO_REG_SET_P (setjmp_crosses, regno)); +} + +/* Walk the tree of blocks describing the binding levels within a + function and warn about variables the might be killed by setjmp or + vfork. This is done after calling flow_analysis before register + allocation since that will clobber the pseudo-regs to hard + regs. */ + +static void +setjmp_vars_warning (bitmap setjmp_crosses, tree block) +{ + tree decl, sub; + + for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl)) + { + if (TREE_CODE (decl) == VAR_DECL + && DECL_RTL_SET_P (decl) + && REG_P (DECL_RTL (decl)) + && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl)))) + warning (OPT_Wclobbered, "variable %q+D might be clobbered by" + " %<longjmp%> or %<vfork%>", decl); + } + + for (sub = BLOCK_SUBBLOCKS (block); sub; sub = BLOCK_CHAIN (sub)) + setjmp_vars_warning (setjmp_crosses, sub); +} + +/* Do the appropriate part of setjmp_vars_warning + but for arguments instead of local variables. */ + +static void +setjmp_args_warning (bitmap setjmp_crosses) +{ + tree decl; + for (decl = DECL_ARGUMENTS (current_function_decl); + decl; decl = TREE_CHAIN (decl)) + if (DECL_RTL (decl) != 0 + && REG_P (DECL_RTL (decl)) + && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl)))) + warning (OPT_Wclobbered, + "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>", + decl); +} + +/* Generate warning messages for variables live across setjmp. */ + +void +generate_setjmp_warnings (void) +{ + bitmap setjmp_crosses = regstat_get_setjmp_crosses (); + + if (n_basic_blocks == NUM_FIXED_BLOCKS + || bitmap_empty_p (setjmp_crosses)) + return; + + setjmp_vars_warning (setjmp_crosses, DECL_INITIAL (current_function_decl)); + setjmp_args_warning (setjmp_crosses); +} + + +/* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END}, + and create duplicate blocks. */ +/* ??? Need an option to either create block fragments or to create + abstract origin duplicates of a source block. It really depends + on what optimization has been performed. */ + +void +reorder_blocks (void) +{ + tree block = DECL_INITIAL (current_function_decl); + VEC(tree,heap) *block_stack; + + if (block == NULL_TREE) + return; + + block_stack = VEC_alloc (tree, heap, 10); + + /* Reset the TREE_ASM_WRITTEN bit for all blocks. */ + clear_block_marks (block); + + /* Prune the old trees away, so that they don't get in the way. */ + BLOCK_SUBBLOCKS (block) = NULL_TREE; + BLOCK_CHAIN (block) = NULL_TREE; + + /* Recreate the block tree from the note nesting. */ + reorder_blocks_1 (get_insns (), block, &block_stack); + BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block)); + + VEC_free (tree, heap, block_stack); +} + +/* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */ + +void +clear_block_marks (tree block) +{ + while (block) + { + TREE_ASM_WRITTEN (block) = 0; + clear_block_marks (BLOCK_SUBBLOCKS (block)); + block = BLOCK_CHAIN (block); + } +} + +static void +reorder_blocks_1 (rtx insns, tree current_block, VEC(tree,heap) **p_block_stack) +{ + rtx insn; + + for (insn = insns; insn; insn = NEXT_INSN (insn)) + { + if (NOTE_P (insn)) + { + if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_BEG) + { + tree block = NOTE_BLOCK (insn); + tree origin; + + origin = (BLOCK_FRAGMENT_ORIGIN (block) + ? BLOCK_FRAGMENT_ORIGIN (block) + : block); + + /* If we have seen this block before, that means it now + spans multiple address regions. Create a new fragment. */ + if (TREE_ASM_WRITTEN (block)) + { + tree new_block = copy_node (block); + + BLOCK_FRAGMENT_ORIGIN (new_block) = origin; + BLOCK_FRAGMENT_CHAIN (new_block) + = BLOCK_FRAGMENT_CHAIN (origin); + BLOCK_FRAGMENT_CHAIN (origin) = new_block; + + NOTE_BLOCK (insn) = new_block; + block = new_block; + } + + BLOCK_SUBBLOCKS (block) = 0; + TREE_ASM_WRITTEN (block) = 1; + /* When there's only one block for the entire function, + current_block == block and we mustn't do this, it + will cause infinite recursion. */ + if (block != current_block) + { + if (block != origin) + gcc_assert (BLOCK_SUPERCONTEXT (origin) == current_block); + + BLOCK_SUPERCONTEXT (block) = current_block; + BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block); + BLOCK_SUBBLOCKS (current_block) = block; + current_block = origin; + } + VEC_safe_push (tree, heap, *p_block_stack, block); + } + else if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_END) + { + NOTE_BLOCK (insn) = VEC_pop (tree, *p_block_stack); + BLOCK_SUBBLOCKS (current_block) + = blocks_nreverse (BLOCK_SUBBLOCKS (current_block)); + current_block = BLOCK_SUPERCONTEXT (current_block); + } + } + } +} + +/* Reverse the order of elements in the chain T of blocks, + and return the new head of the chain (old last element). */ + +tree +blocks_nreverse (tree t) +{ + tree prev = 0, decl, next; + for (decl = t; decl; decl = next) + { + next = BLOCK_CHAIN (decl); + BLOCK_CHAIN (decl) = prev; + prev = decl; + } + return prev; +} + +/* Count the subblocks of the list starting with BLOCK. If VECTOR is + non-NULL, list them all into VECTOR, in a depth-first preorder + traversal of the block tree. Also clear TREE_ASM_WRITTEN in all + blocks. */ + +static int +all_blocks (tree block, tree *vector) +{ + int n_blocks = 0; + + while (block) + { + TREE_ASM_WRITTEN (block) = 0; + + /* Record this block. */ + if (vector) + vector[n_blocks] = block; + + ++n_blocks; + + /* Record the subblocks, and their subblocks... */ + n_blocks += all_blocks (BLOCK_SUBBLOCKS (block), + vector ? vector + n_blocks : 0); + block = BLOCK_CHAIN (block); + } + + return n_blocks; +} + +/* Return a vector containing all the blocks rooted at BLOCK. The + number of elements in the vector is stored in N_BLOCKS_P. The + vector is dynamically allocated; it is the caller's responsibility + to call `free' on the pointer returned. */ + +static tree * +get_block_vector (tree block, int *n_blocks_p) +{ + tree *block_vector; + + *n_blocks_p = all_blocks (block, NULL); + block_vector = XNEWVEC (tree, *n_blocks_p); + all_blocks (block, block_vector); + + return block_vector; +} + +static GTY(()) int next_block_index = 2; + +/* Set BLOCK_NUMBER for all the blocks in FN. */ + +void +number_blocks (tree fn) +{ + int i; + int n_blocks; + tree *block_vector; + + /* For SDB and XCOFF debugging output, we start numbering the blocks + from 1 within each function, rather than keeping a running + count. */ +#if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO) + if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG) + next_block_index = 1; +#endif + + block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks); + + /* The top-level BLOCK isn't numbered at all. */ + for (i = 1; i < n_blocks; ++i) + /* We number the blocks from two. */ + BLOCK_NUMBER (block_vector[i]) = next_block_index++; + + free (block_vector); + + return; +} + +/* If VAR is present in a subblock of BLOCK, return the subblock. */ + +tree +debug_find_var_in_block_tree (tree var, tree block) +{ + tree t; + + for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t)) + if (t == var) + return block; + + for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t)) + { + tree ret = debug_find_var_in_block_tree (var, t); + if (ret) + return ret; + } + + return NULL_TREE; +} + +/* Keep track of whether we're in a dummy function context. If we are, + we don't want to invoke the set_current_function hook, because we'll + get into trouble if the hook calls target_reinit () recursively or + when the initial initialization is not yet complete. */ + +static bool in_dummy_function; + +/* Invoke the target hook when setting cfun. Update the optimization options + if the function uses different options than the default. */ + +static void +invoke_set_current_function_hook (tree fndecl) +{ + if (!in_dummy_function) + { + tree opts = ((fndecl) + ? DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl) + : optimization_default_node); + + if (!opts) + opts = optimization_default_node; + + /* Change optimization options if needed. */ + if (optimization_current_node != opts) + { + optimization_current_node = opts; + cl_optimization_restore (TREE_OPTIMIZATION (opts)); + } + + targetm.set_current_function (fndecl); + } +} + +/* cfun should never be set directly; use this function. */ + +void +set_cfun (struct function *new_cfun) +{ + if (cfun != new_cfun) + { + cfun = new_cfun; + invoke_set_current_function_hook (new_cfun ? new_cfun->decl : NULL_TREE); + } +} + +/* Initialized with NOGC, making this poisonous to the garbage collector. */ + +static VEC(function_p,heap) *cfun_stack; + +/* Push the current cfun onto the stack, and set cfun to new_cfun. */ + +void +push_cfun (struct function *new_cfun) +{ + VEC_safe_push (function_p, heap, cfun_stack, cfun); + set_cfun (new_cfun); +} + +/* Pop cfun from the stack. */ + +void +pop_cfun (void) +{ + struct function *new_cfun = VEC_pop (function_p, cfun_stack); + set_cfun (new_cfun); +} + +/* Return value of funcdef and increase it. */ +int +get_next_funcdef_no (void) +{ + return funcdef_no++; +} + +/* Allocate a function structure for FNDECL and set its contents + to the defaults. Set cfun to the newly-allocated object. + Some of the helper functions invoked during initialization assume + that cfun has already been set. Therefore, assign the new object + directly into cfun and invoke the back end hook explicitly at the + very end, rather than initializing a temporary and calling set_cfun + on it. + + ABSTRACT_P is true if this is a function that will never be seen by + the middle-end. Such functions are front-end concepts (like C++ + function templates) that do not correspond directly to functions + placed in object files. */ + +void +allocate_struct_function (tree fndecl, bool abstract_p) +{ + tree result; + tree fntype = fndecl ? TREE_TYPE (fndecl) : NULL_TREE; + + cfun = GGC_CNEW (struct function); + + cfun->function_frequency = FUNCTION_FREQUENCY_NORMAL; + + init_eh_for_function (); + + if (init_machine_status) + cfun->machine = (*init_machine_status) (); + +#ifdef OVERRIDE_ABI_FORMAT + OVERRIDE_ABI_FORMAT (fndecl); +#endif + + invoke_set_current_function_hook (fndecl); + + if (fndecl != NULL_TREE) + { + DECL_STRUCT_FUNCTION (fndecl) = cfun; + cfun->decl = fndecl; + current_function_funcdef_no = get_next_funcdef_no (); + + result = DECL_RESULT (fndecl); + if (!abstract_p && aggregate_value_p (result, fndecl)) + { +#ifdef PCC_STATIC_STRUCT_RETURN + cfun->returns_pcc_struct = 1; +#endif + cfun->returns_struct = 1; + } + + cfun->stdarg + = (fntype + && TYPE_ARG_TYPES (fntype) != 0 + && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype))) + != void_type_node)); + + /* Assume all registers in stdarg functions need to be saved. */ + cfun->va_list_gpr_size = VA_LIST_MAX_GPR_SIZE; + cfun->va_list_fpr_size = VA_LIST_MAX_FPR_SIZE; + } +} + +/* This is like allocate_struct_function, but pushes a new cfun for FNDECL + instead of just setting it. */ + +void +push_struct_function (tree fndecl) +{ + VEC_safe_push (function_p, heap, cfun_stack, cfun); + allocate_struct_function (fndecl, false); +} + +/* Reset cfun, and other non-struct-function variables to defaults as + appropriate for emitting rtl at the start of a function. */ + +static void +prepare_function_start (void) +{ + gcc_assert (!crtl->emit.x_last_insn); + init_temp_slots (); + init_emit (); + init_varasm_status (); + init_expr (); + default_rtl_profile (); + + cse_not_expected = ! optimize; + + /* Caller save not needed yet. */ + caller_save_needed = 0; + + /* We haven't done register allocation yet. */ + reg_renumber = 0; + + /* Indicate that we have not instantiated virtual registers yet. */ + virtuals_instantiated = 0; + + /* Indicate that we want CONCATs now. */ + generating_concat_p = 1; + + /* Indicate we have no need of a frame pointer yet. */ + frame_pointer_needed = 0; +} + +/* Initialize the rtl expansion mechanism so that we can do simple things + like generate sequences. This is used to provide a context during global + initialization of some passes. You must call expand_dummy_function_end + to exit this context. */ + +void +init_dummy_function_start (void) +{ + gcc_assert (!in_dummy_function); + in_dummy_function = true; + push_struct_function (NULL_TREE); + prepare_function_start (); +} + +/* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node) + and initialize static variables for generating RTL for the statements + of the function. */ + +void +init_function_start (tree subr) +{ + if (subr && DECL_STRUCT_FUNCTION (subr)) + set_cfun (DECL_STRUCT_FUNCTION (subr)); + else + allocate_struct_function (subr, false); + prepare_function_start (); + + /* Warn if this value is an aggregate type, + regardless of which calling convention we are using for it. */ + if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr)))) + warning (OPT_Waggregate_return, "function returns an aggregate"); +} + +/* Make sure all values used by the optimization passes have sane + defaults. */ +unsigned int +init_function_for_compilation (void) +{ + reg_renumber = 0; + + /* No prologue/epilogue insns yet. Make sure that these vectors are + empty. */ + gcc_assert (VEC_length (int, prologue) == 0); + gcc_assert (VEC_length (int, epilogue) == 0); + gcc_assert (VEC_length (int, sibcall_epilogue) == 0); + return 0; +} + +struct rtl_opt_pass pass_init_function = +{ + { + RTL_PASS, + NULL, /* name */ + NULL, /* gate */ + init_function_for_compilation, /* execute */ + NULL, /* sub */ + NULL, /* next */ + 0, /* static_pass_number */ + 0, /* tv_id */ + 0, /* properties_required */ + 0, /* properties_provided */ + 0, /* properties_destroyed */ + 0, /* todo_flags_start */ + 0 /* todo_flags_finish */ + } +}; + + +void +expand_main_function (void) +{ +#if (defined(INVOKE__main) \ + || (!defined(HAS_INIT_SECTION) \ + && !defined(INIT_SECTION_ASM_OP) \ + && !defined(INIT_ARRAY_SECTION_ASM_OP))) + emit_library_call (init_one_libfunc (NAME__MAIN), LCT_NORMAL, VOIDmode, 0); +#endif +} + +/* Expand code to initialize the stack_protect_guard. This is invoked at + the beginning of a function to be protected. */ + +#ifndef HAVE_stack_protect_set +# define HAVE_stack_protect_set 0 +# define gen_stack_protect_set(x,y) (gcc_unreachable (), NULL_RTX) +#endif + +void +stack_protect_prologue (void) +{ + tree guard_decl = targetm.stack_protect_guard (); + rtx x, y; + + /* Avoid expand_expr here, because we don't want guard_decl pulled + into registers unless absolutely necessary. And we know that + crtl->stack_protect_guard is a local stack slot, so this skips + all the fluff. */ + x = validize_mem (DECL_RTL (crtl->stack_protect_guard)); + y = validize_mem (DECL_RTL (guard_decl)); + + /* Allow the target to copy from Y to X without leaking Y into a + register. */ + if (HAVE_stack_protect_set) + { + rtx insn = gen_stack_protect_set (x, y); + if (insn) + { + emit_insn (insn); + return; + } + } + + /* Otherwise do a straight move. */ + emit_move_insn (x, y); +} + +/* Expand code to verify the stack_protect_guard. This is invoked at + the end of a function to be protected. */ + +#ifndef HAVE_stack_protect_test +# define HAVE_stack_protect_test 0 +# define gen_stack_protect_test(x, y, z) (gcc_unreachable (), NULL_RTX) +#endif + +void +stack_protect_epilogue (void) +{ + tree guard_decl = targetm.stack_protect_guard (); + rtx label = gen_label_rtx (); + rtx x, y, tmp; + + /* Avoid expand_expr here, because we don't want guard_decl pulled + into registers unless absolutely necessary. And we know that + crtl->stack_protect_guard is a local stack slot, so this skips + all the fluff. */ + x = validize_mem (DECL_RTL (crtl->stack_protect_guard)); + y = validize_mem (DECL_RTL (guard_decl)); + + /* Allow the target to compare Y with X without leaking either into + a register. */ + switch (HAVE_stack_protect_test != 0) + { + case 1: + tmp = gen_stack_protect_test (x, y, label); + if (tmp) + { + emit_insn (tmp); + break; + } + /* FALLTHRU */ + + default: + emit_cmp_and_jump_insns (x, y, EQ, NULL_RTX, ptr_mode, 1, label); + break; + } + + /* The noreturn predictor has been moved to the tree level. The rtl-level + predictors estimate this branch about 20%, which isn't enough to get + things moved out of line. Since this is the only extant case of adding + a noreturn function at the rtl level, it doesn't seem worth doing ought + except adding the prediction by hand. */ + tmp = get_last_insn (); + if (JUMP_P (tmp)) + predict_insn_def (tmp, PRED_NORETURN, TAKEN); + + expand_expr_stmt (targetm.stack_protect_fail ()); + emit_label (label); +} + +/* Start the RTL for a new function, and set variables used for + emitting RTL. + SUBR is the FUNCTION_DECL node. + PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with + the function's parameters, which must be run at any return statement. */ + +void +expand_function_start (tree subr) +{ + /* Make sure volatile mem refs aren't considered + valid operands of arithmetic insns. */ + init_recog_no_volatile (); + + crtl->profile + = (profile_flag + && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr)); + + crtl->limit_stack + = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr)); + + /* Make the label for return statements to jump to. Do not special + case machines with special return instructions -- they will be + handled later during jump, ifcvt, or epilogue creation. */ + return_label = gen_label_rtx (); + + /* Initialize rtx used to return the value. */ + /* Do this before assign_parms so that we copy the struct value address + before any library calls that assign parms might generate. */ + + /* Decide whether to return the value in memory or in a register. */ + if (aggregate_value_p (DECL_RESULT (subr), subr)) + { + /* Returning something that won't go in a register. */ + rtx value_address = 0; + +#ifdef PCC_STATIC_STRUCT_RETURN + if (cfun->returns_pcc_struct) + { + int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr))); + value_address = assemble_static_space (size); + } + else +#endif + { + rtx sv = targetm.calls.struct_value_rtx (TREE_TYPE (subr), 2); + /* Expect to be passed the address of a place to store the value. + If it is passed as an argument, assign_parms will take care of + it. */ + if (sv) + { + value_address = gen_reg_rtx (Pmode); + emit_move_insn (value_address, sv); + } + } + if (value_address) + { + rtx x = value_address; + if (!DECL_BY_REFERENCE (DECL_RESULT (subr))) + { + x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), x); + set_mem_attributes (x, DECL_RESULT (subr), 1); + } + SET_DECL_RTL (DECL_RESULT (subr), x); + } + } + else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode) + /* If return mode is void, this decl rtl should not be used. */ + SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX); + else + { + /* Compute the return values into a pseudo reg, which we will copy + into the true return register after the cleanups are done. */ + tree return_type = TREE_TYPE (DECL_RESULT (subr)); + if (TYPE_MODE (return_type) != BLKmode + && targetm.calls.return_in_msb (return_type)) + /* expand_function_end will insert the appropriate padding in + this case. Use the return value's natural (unpadded) mode + within the function proper. */ + SET_DECL_RTL (DECL_RESULT (subr), + gen_reg_rtx (TYPE_MODE (return_type))); + else + { + /* In order to figure out what mode to use for the pseudo, we + figure out what the mode of the eventual return register will + actually be, and use that. */ + rtx hard_reg = hard_function_value (return_type, subr, 0, 1); + + /* Structures that are returned in registers are not + aggregate_value_p, so we may see a PARALLEL or a REG. */ + if (REG_P (hard_reg)) + SET_DECL_RTL (DECL_RESULT (subr), + gen_reg_rtx (GET_MODE (hard_reg))); + else + { + gcc_assert (GET_CODE (hard_reg) == PARALLEL); + SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg)); + } + } + + /* Set DECL_REGISTER flag so that expand_function_end will copy the + result to the real return register(s). */ + DECL_REGISTER (DECL_RESULT (subr)) = 1; + } + + /* Initialize rtx for parameters and local variables. + In some cases this requires emitting insns. */ + assign_parms (subr); + + /* If function gets a static chain arg, store it. */ + if (cfun->static_chain_decl) + { + tree parm = cfun->static_chain_decl; + rtx local = gen_reg_rtx (Pmode); + + set_decl_incoming_rtl (parm, static_chain_incoming_rtx, false); + SET_DECL_RTL (parm, local); + mark_reg_pointer (local, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm)))); + + emit_move_insn (local, static_chain_incoming_rtx); + } + + /* If the function receives a non-local goto, then store the + bits we need to restore the frame pointer. */ + if (cfun->nonlocal_goto_save_area) + { + tree t_save; + rtx r_save; + + /* ??? We need to do this save early. Unfortunately here is + before the frame variable gets declared. Help out... */ + tree var = TREE_OPERAND (cfun->nonlocal_goto_save_area, 0); + if (!DECL_RTL_SET_P (var)) + expand_decl (var); + + t_save = build4 (ARRAY_REF, ptr_type_node, + cfun->nonlocal_goto_save_area, + integer_zero_node, NULL_TREE, NULL_TREE); + r_save = expand_expr (t_save, NULL_RTX, VOIDmode, EXPAND_WRITE); + r_save = convert_memory_address (Pmode, r_save); + + emit_move_insn (r_save, targetm.builtin_setjmp_frame_value ()); + update_nonlocal_goto_save_area (); + } + + /* The following was moved from init_function_start. + The move is supposed to make sdb output more accurate. */ + /* Indicate the beginning of the function body, + as opposed to parm setup. */ + emit_note (NOTE_INSN_FUNCTION_BEG); + + gcc_assert (NOTE_P (get_last_insn ())); + + parm_birth_insn = get_last_insn (); + + if (crtl->profile) + { +#ifdef PROFILE_HOOK + PROFILE_HOOK (current_function_funcdef_no); +#endif + } + + /* After the display initializations is where the stack checking + probe should go. */ + if(flag_stack_check) + stack_check_probe_note = emit_note (NOTE_INSN_DELETED); + + /* Make sure there is a line number after the function entry setup code. */ + force_next_line_note (); +} + +/* Undo the effects of init_dummy_function_start. */ +void +expand_dummy_function_end (void) +{ + gcc_assert (in_dummy_function); + + /* End any sequences that failed to be closed due to syntax errors. */ + while (in_sequence_p ()) + end_sequence (); + + /* Outside function body, can't compute type's actual size + until next function's body starts. */ + + free_after_parsing (cfun); + free_after_compilation (cfun); + pop_cfun (); + in_dummy_function = false; +} + +/* Call DOIT for each hard register used as a return value from + the current function. */ + +void +diddle_return_value (void (*doit) (rtx, void *), void *arg) +{ + rtx outgoing = crtl->return_rtx; + + if (! outgoing) + return; + + if (REG_P (outgoing)) + (*doit) (outgoing, arg); + else if (GET_CODE (outgoing) == PARALLEL) + { + int i; + + for (i = 0; i < XVECLEN (outgoing, 0); i++) + { + rtx x = XEXP (XVECEXP (outgoing, 0, i), 0); + + if (REG_P (x) && REGNO (x) < FIRST_PSEUDO_REGISTER) + (*doit) (x, arg); + } + } +} + +static void +do_clobber_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED) +{ + emit_clobber (reg); +} + +void +clobber_return_register (void) +{ + diddle_return_value (do_clobber_return_reg, NULL); + + /* In case we do use pseudo to return value, clobber it too. */ + if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl))) + { + tree decl_result = DECL_RESULT (current_function_decl); + rtx decl_rtl = DECL_RTL (decl_result); + if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER) + { + do_clobber_return_reg (decl_rtl, NULL); + } + } +} + +static void +do_use_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED) +{ + emit_use (reg); +} + +static void +use_return_register (void) +{ + diddle_return_value (do_use_return_reg, NULL); +} + +/* Possibly warn about unused parameters. */ +void +do_warn_unused_parameter (tree fn) +{ + tree decl; + + for (decl = DECL_ARGUMENTS (fn); + decl; decl = TREE_CHAIN (decl)) + if (!TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL + && DECL_NAME (decl) && !DECL_ARTIFICIAL (decl) + && !TREE_NO_WARNING (decl)) + warning (OPT_Wunused_parameter, "unused parameter %q+D", decl); +} + +static GTY(()) rtx initial_trampoline; + +/* Generate RTL for the end of the current function. */ + +void +expand_function_end (void) +{ + rtx clobber_after; + + /* If arg_pointer_save_area was referenced only from a nested + function, we will not have initialized it yet. Do that now. */ + if (arg_pointer_save_area && ! crtl->arg_pointer_save_area_init) + get_arg_pointer_save_area (); + + /* If we are doing generic stack checking and this function makes calls, + do a stack probe at the start of the function to ensure we have enough + space for another stack frame. */ + if (flag_stack_check == GENERIC_STACK_CHECK) + { + rtx insn, seq; + + for (insn = get_insns (); insn; insn = NEXT_INSN (insn)) + if (CALL_P (insn)) + { + start_sequence (); + probe_stack_range (STACK_OLD_CHECK_PROTECT, + GEN_INT (STACK_CHECK_MAX_FRAME_SIZE)); + seq = get_insns (); + end_sequence (); + emit_insn_before (seq, stack_check_probe_note); + break; + } + } + + /* End any sequences that failed to be closed due to syntax errors. */ + while (in_sequence_p ()) + end_sequence (); + + clear_pending_stack_adjust (); + do_pending_stack_adjust (); + + /* Output a linenumber for the end of the function. + SDB depends on this. */ + force_next_line_note (); + set_curr_insn_source_location (input_location); + + /* Before the return label (if any), clobber the return + registers so that they are not propagated live to the rest of + the function. This can only happen with functions that drop + through; if there had been a return statement, there would + have either been a return rtx, or a jump to the return label. + + We delay actual code generation after the current_function_value_rtx + is computed. */ + clobber_after = get_last_insn (); + + /* Output the label for the actual return from the function. */ + emit_label (return_label); + + if (USING_SJLJ_EXCEPTIONS) + { + /* Let except.c know where it should emit the call to unregister + the function context for sjlj exceptions. */ + if (flag_exceptions) + sjlj_emit_function_exit_after (get_last_insn ()); + } + else + { + /* We want to ensure that instructions that may trap are not + moved into the epilogue by scheduling, because we don't + always emit unwind information for the epilogue. */ + if (flag_non_call_exceptions) + emit_insn (gen_blockage ()); + } + + /* If this is an implementation of throw, do what's necessary to + communicate between __builtin_eh_return and the epilogue. */ + expand_eh_return (); + + /* If scalar return value was computed in a pseudo-reg, or was a named + return value that got dumped to the stack, copy that to the hard + return register. */ + if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl))) + { + tree decl_result = DECL_RESULT (current_function_decl); + rtx decl_rtl = DECL_RTL (decl_result); + + if (REG_P (decl_rtl) + ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER + : DECL_REGISTER (decl_result)) + { + rtx real_decl_rtl = crtl->return_rtx; + + /* This should be set in assign_parms. */ + gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl)); + + /* If this is a BLKmode structure being returned in registers, + then use the mode computed in expand_return. Note that if + decl_rtl is memory, then its mode may have been changed, + but that crtl->return_rtx has not. */ + if (GET_MODE (real_decl_rtl) == BLKmode) + PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl)); + + /* If a non-BLKmode return value should be padded at the least + significant end of the register, shift it left by the appropriate + amount. BLKmode results are handled using the group load/store + machinery. */ + if (TYPE_MODE (TREE_TYPE (decl_result)) != BLKmode + && targetm.calls.return_in_msb (TREE_TYPE (decl_result))) + { + emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl), + REGNO (real_decl_rtl)), + decl_rtl); + shift_return_value (GET_MODE (decl_rtl), true, real_decl_rtl); + } + /* If a named return value dumped decl_return to memory, then + we may need to re-do the PROMOTE_MODE signed/unsigned + extension. */ + else if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl)) + { + int unsignedp = TYPE_UNSIGNED (TREE_TYPE (decl_result)); + + if (targetm.calls.promote_function_return (TREE_TYPE (current_function_decl))) + promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl), + &unsignedp, 1); + + convert_move (real_decl_rtl, decl_rtl, unsignedp); + } + else if (GET_CODE (real_decl_rtl) == PARALLEL) + { + /* If expand_function_start has created a PARALLEL for decl_rtl, + move the result to the real return registers. Otherwise, do + a group load from decl_rtl for a named return. */ + if (GET_CODE (decl_rtl) == PARALLEL) + emit_group_move (real_decl_rtl, decl_rtl); + else + emit_group_load (real_decl_rtl, decl_rtl, + TREE_TYPE (decl_result), + int_size_in_bytes (TREE_TYPE (decl_result))); + } + /* In the case of complex integer modes smaller than a word, we'll + need to generate some non-trivial bitfield insertions. Do that + on a pseudo and not the hard register. */ + else if (GET_CODE (decl_rtl) == CONCAT + && GET_MODE_CLASS (GET_MODE (decl_rtl)) == MODE_COMPLEX_INT + && GET_MODE_BITSIZE (GET_MODE (decl_rtl)) <= BITS_PER_WORD) + { + int old_generating_concat_p; + rtx tmp; + + old_generating_concat_p = generating_concat_p; + generating_concat_p = 0; + tmp = gen_reg_rtx (GET_MODE (decl_rtl)); + generating_concat_p = old_generating_concat_p; + + emit_move_insn (tmp, decl_rtl); + emit_move_insn (real_decl_rtl, tmp); + } + else + emit_move_insn (real_decl_rtl, decl_rtl); + } + } + + /* If returning a structure, arrange to return the address of the value + in a place where debuggers expect to find it. + + If returning a structure PCC style, + the caller also depends on this value. + And cfun->returns_pcc_struct is not necessarily set. */ + if (cfun->returns_struct + || cfun->returns_pcc_struct) + { + rtx value_address = DECL_RTL (DECL_RESULT (current_function_decl)); + tree type = TREE_TYPE (DECL_RESULT (current_function_decl)); + rtx outgoing; + + if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl))) + type = TREE_TYPE (type); + else + value_address = XEXP (value_address, 0); + + outgoing = targetm.calls.function_value (build_pointer_type (type), + current_function_decl, true); + + /* Mark this as a function return value so integrate will delete the + assignment and USE below when inlining this function. */ + REG_FUNCTION_VALUE_P (outgoing) = 1; + + /* The address may be ptr_mode and OUTGOING may be Pmode. */ + value_address = convert_memory_address (GET_MODE (outgoing), + value_address); + + emit_move_insn (outgoing, value_address); + + /* Show return register used to hold result (in this case the address + of the result. */ + crtl->return_rtx = outgoing; + } + + /* Emit the actual code to clobber return register. */ + { + rtx seq; + + start_sequence (); + clobber_return_register (); + expand_naked_return (); + seq = get_insns (); + end_sequence (); + + emit_insn_after (seq, clobber_after); + } + + /* Output the label for the naked return from the function. */ + emit_label (naked_return_label); + + /* @@@ This is a kludge. We want to ensure that instructions that + may trap are not moved into the epilogue by scheduling, because + we don't always emit unwind information for the epilogue. */ + if (! USING_SJLJ_EXCEPTIONS && flag_non_call_exceptions) + emit_insn (gen_blockage ()); + + /* If stack protection is enabled for this function, check the guard. */ + if (crtl->stack_protect_guard) + stack_protect_epilogue (); + + /* If we had calls to alloca, and this machine needs + an accurate stack pointer to exit the function, + insert some code to save and restore the stack pointer. */ + if (! EXIT_IGNORE_STACK + && cfun->calls_alloca) + { + rtx tem = 0; + + emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn); + emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX); + } + + /* ??? This should no longer be necessary since stupid is no longer with + us, but there are some parts of the compiler (eg reload_combine, and + sh mach_dep_reorg) that still try and compute their own lifetime info + instead of using the general framework. */ + use_return_register (); +} + +rtx +get_arg_pointer_save_area (void) +{ + rtx ret = arg_pointer_save_area; + + if (! ret) + { + ret = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0); + arg_pointer_save_area = ret; + } + + if (! crtl->arg_pointer_save_area_init) + { + rtx seq; + + /* Save the arg pointer at the beginning of the function. The + generated stack slot may not be a valid memory address, so we + have to check it and fix it if necessary. */ + start_sequence (); + emit_move_insn (validize_mem (ret), + crtl->args.internal_arg_pointer); + seq = get_insns (); + end_sequence (); + + push_topmost_sequence (); + emit_insn_after (seq, entry_of_function ()); + pop_topmost_sequence (); + } + + return ret; +} + +/* Extend a vector that records the INSN_UIDs of INSNS + (a list of one or more insns). */ + +static void +record_insns (rtx insns, VEC(int,heap) **vecp) +{ + rtx tmp; + + for (tmp = insns; tmp != NULL_RTX; tmp = NEXT_INSN (tmp)) + VEC_safe_push (int, heap, *vecp, INSN_UID (tmp)); +} + +/* Set the locator of the insn chain starting at INSN to LOC. */ +static void +set_insn_locators (rtx insn, int loc) +{ + while (insn != NULL_RTX) + { + if (INSN_P (insn)) + INSN_LOCATOR (insn) = loc; + insn = NEXT_INSN (insn); + } +} + +/* Determine how many INSN_UIDs in VEC are part of INSN. Because we can + be running after reorg, SEQUENCE rtl is possible. */ + +static int +contains (const_rtx insn, VEC(int,heap) **vec) +{ + int i, j; + + if (NONJUMP_INSN_P (insn) + && GET_CODE (PATTERN (insn)) == SEQUENCE) + { + int count = 0; + for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--) + for (j = VEC_length (int, *vec) - 1; j >= 0; --j) + if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) + == VEC_index (int, *vec, j)) + count++; + return count; + } + else + { + for (j = VEC_length (int, *vec) - 1; j >= 0; --j) + if (INSN_UID (insn) == VEC_index (int, *vec, j)) + return 1; + } + return 0; +} + +int +prologue_epilogue_contains (const_rtx insn) +{ + if (contains (insn, &prologue)) + return 1; + if (contains (insn, &epilogue)) + return 1; + return 0; +} + +int +sibcall_epilogue_contains (const_rtx insn) +{ + if (sibcall_epilogue) + return contains (insn, &sibcall_epilogue); + return 0; +} + +#ifdef HAVE_return +/* Insert gen_return at the end of block BB. This also means updating + block_for_insn appropriately. */ + +static void +emit_return_into_block (basic_block bb) +{ + emit_jump_insn_after (gen_return (), BB_END (bb)); +} +#endif /* HAVE_return */ + +/* Generate the prologue and epilogue RTL if the machine supports it. Thread + this into place with notes indicating where the prologue ends and where + the epilogue begins. Update the basic block information when possible. */ + +static void +thread_prologue_and_epilogue_insns (void) +{ + int inserted = 0; + edge e; +#if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue) + rtx seq; +#endif +#if defined (HAVE_epilogue) || defined(HAVE_return) + rtx epilogue_end = NULL_RTX; +#endif + edge_iterator ei; + + rtl_profile_for_bb (ENTRY_BLOCK_PTR); +#ifdef HAVE_prologue + if (HAVE_prologue) + { + start_sequence (); + seq = gen_prologue (); + emit_insn (seq); + + /* Insert an explicit USE for the frame pointer + if the profiling is on and the frame pointer is required. */ + if (crtl->profile && frame_pointer_needed) + emit_use (hard_frame_pointer_rtx); + + /* Retain a map of the prologue insns. */ + record_insns (seq, &prologue); + emit_note (NOTE_INSN_PROLOGUE_END); + +#ifndef PROFILE_BEFORE_PROLOGUE + /* Ensure that instructions are not moved into the prologue when + profiling is on. The call to the profiling routine can be + emitted within the live range of a call-clobbered register. */ + if (crtl->profile) + emit_insn (gen_blockage ()); +#endif + + seq = get_insns (); + end_sequence (); + set_insn_locators (seq, prologue_locator); + + /* Can't deal with multiple successors of the entry block + at the moment. Function should always have at least one + entry point. */ + gcc_assert (single_succ_p (ENTRY_BLOCK_PTR)); + + insert_insn_on_edge (seq, single_succ_edge (ENTRY_BLOCK_PTR)); + inserted = 1; + } +#endif + + /* If the exit block has no non-fake predecessors, we don't need + an epilogue. */ + FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds) + if ((e->flags & EDGE_FAKE) == 0) + break; + if (e == NULL) + goto epilogue_done; + + rtl_profile_for_bb (EXIT_BLOCK_PTR); +#ifdef HAVE_return + if (optimize && HAVE_return) + { + /* If we're allowed to generate a simple return instruction, + then by definition we don't need a full epilogue. Examine + the block that falls through to EXIT. If it does not + contain any code, examine its predecessors and try to + emit (conditional) return instructions. */ + + basic_block last; + rtx label; + + FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds) + if (e->flags & EDGE_FALLTHRU) + break; + if (e == NULL) + goto epilogue_done; + last = e->src; + + /* Verify that there are no active instructions in the last block. */ + label = BB_END (last); + while (label && !LABEL_P (label)) + { + if (active_insn_p (label)) + break; + label = PREV_INSN (label); + } + + if (BB_HEAD (last) == label && LABEL_P (label)) + { + edge_iterator ei2; + + for (ei2 = ei_start (last->preds); (e = ei_safe_edge (ei2)); ) + { + basic_block bb = e->src; + rtx jump; + + if (bb == ENTRY_BLOCK_PTR) + { + ei_next (&ei2); + continue; + } + + jump = BB_END (bb); + if (!JUMP_P (jump) || JUMP_LABEL (jump) != label) + { + ei_next (&ei2); + continue; + } + + /* If we have an unconditional jump, we can replace that + with a simple return instruction. */ + if (simplejump_p (jump)) + { + emit_return_into_block (bb); + delete_insn (jump); + } + + /* If we have a conditional jump, we can try to replace + that with a conditional return instruction. */ + else if (condjump_p (jump)) + { + if (! redirect_jump (jump, 0, 0)) + { + ei_next (&ei2); + continue; + } + + /* If this block has only one successor, it both jumps + and falls through to the fallthru block, so we can't + delete the edge. */ + if (single_succ_p (bb)) + { + ei_next (&ei2); + continue; + } + } + else + { + ei_next (&ei2); + continue; + } + + /* Fix up the CFG for the successful change we just made. */ + redirect_edge_succ (e, EXIT_BLOCK_PTR); + } + + /* Emit a return insn for the exit fallthru block. Whether + this is still reachable will be determined later. */ + + emit_barrier_after (BB_END (last)); + emit_return_into_block (last); + epilogue_end = BB_END (last); + single_succ_edge (last)->flags &= ~EDGE_FALLTHRU; + goto epilogue_done; + } + } +#endif + /* Find the edge that falls through to EXIT. Other edges may exist + due to RETURN instructions, but those don't need epilogues. + There really shouldn't be a mixture -- either all should have + been converted or none, however... */ + + FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds) + if (e->flags & EDGE_FALLTHRU) + break; + if (e == NULL) + goto epilogue_done; + +#ifdef HAVE_epilogue + if (HAVE_epilogue) + { + start_sequence (); + epilogue_end = emit_note (NOTE_INSN_EPILOGUE_BEG); + seq = gen_epilogue (); + emit_jump_insn (seq); + + /* Retain a map of the epilogue insns. */ + record_insns (seq, &epilogue); + set_insn_locators (seq, epilogue_locator); + + seq = get_insns (); + end_sequence (); + + insert_insn_on_edge (seq, e); + inserted = 1; + } + else +#endif + { + basic_block cur_bb; + + if (! next_active_insn (BB_END (e->src))) + goto epilogue_done; + /* We have a fall-through edge to the exit block, the source is not + at the end of the function, and there will be an assembler epilogue + at the end of the function. + We can't use force_nonfallthru here, because that would try to + use return. Inserting a jump 'by hand' is extremely messy, so + we take advantage of cfg_layout_finalize using + fixup_fallthru_exit_predecessor. */ + cfg_layout_initialize (0); + FOR_EACH_BB (cur_bb) + if (cur_bb->index >= NUM_FIXED_BLOCKS + && cur_bb->next_bb->index >= NUM_FIXED_BLOCKS) + cur_bb->aux = cur_bb->next_bb; + cfg_layout_finalize (); + } +epilogue_done: + default_rtl_profile (); + + if (inserted) + { + commit_edge_insertions (); + + /* The epilogue insns we inserted may cause the exit edge to no longer + be fallthru. */ + FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds) + { + if (((e->flags & EDGE_FALLTHRU) != 0) + && returnjump_p (BB_END (e->src))) + e->flags &= ~EDGE_FALLTHRU; + } + } + +#ifdef HAVE_sibcall_epilogue + /* Emit sibling epilogues before any sibling call sites. */ + for (ei = ei_start (EXIT_BLOCK_PTR->preds); (e = ei_safe_edge (ei)); ) + { + basic_block bb = e->src; + rtx insn = BB_END (bb); + + if (!CALL_P (insn) + || ! SIBLING_CALL_P (insn)) + { + ei_next (&ei); + continue; + } + + start_sequence (); + emit_insn (gen_sibcall_epilogue ()); + seq = get_insns (); + end_sequence (); + + /* Retain a map of the epilogue insns. Used in life analysis to + avoid getting rid of sibcall epilogue insns. Do this before we + actually emit the sequence. */ + record_insns (seq, &sibcall_epilogue); + set_insn_locators (seq, epilogue_locator); + + emit_insn_before (seq, insn); + ei_next (&ei); + } +#endif + +#ifdef HAVE_epilogue + if (epilogue_end) + { + rtx insn, next; + + /* Similarly, move any line notes that appear after the epilogue. + There is no need, however, to be quite so anal about the existence + of such a note. Also possibly move + NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug + info generation. */ + for (insn = epilogue_end; insn; insn = next) + { + next = NEXT_INSN (insn); + if (NOTE_P (insn) + && (NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG)) + reorder_insns (insn, insn, PREV_INSN (epilogue_end)); + } + } +#endif + + /* Threading the prologue and epilogue changes the artificial refs + in the entry and exit blocks. */ + epilogue_completed = 1; + df_update_entry_exit_and_calls (); +} + +/* Reposition the prologue-end and epilogue-begin notes after instruction + scheduling and delayed branch scheduling. */ + +void +reposition_prologue_and_epilogue_notes (void) +{ +#if defined (HAVE_prologue) || defined (HAVE_epilogue) + rtx insn, last, note; + int len; + + if ((len = VEC_length (int, prologue)) > 0) + { + last = 0, note = 0; + + /* Scan from the beginning until we reach the last prologue insn. + We apparently can't depend on basic_block_{head,end} after + reorg has run. */ + for (insn = get_insns (); insn; insn = NEXT_INSN (insn)) + { + if (NOTE_P (insn)) + { + if (NOTE_KIND (insn) == NOTE_INSN_PROLOGUE_END) + note = insn; + } + else if (contains (insn, &prologue)) + { + last = insn; + if (--len == 0) + break; + } + } + + if (last) + { + /* Find the prologue-end note if we haven't already, and + move it to just after the last prologue insn. */ + if (note == 0) + { + for (note = last; (note = NEXT_INSN (note));) + if (NOTE_P (note) + && NOTE_KIND (note) == NOTE_INSN_PROLOGUE_END) + break; + } + + /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */ + if (LABEL_P (last)) + last = NEXT_INSN (last); + reorder_insns (note, note, last); + } + } + + if ((len = VEC_length (int, epilogue)) > 0) + { + last = 0, note = 0; + + /* Scan from the end until we reach the first epilogue insn. + We apparently can't depend on basic_block_{head,end} after + reorg has run. */ + for (insn = get_last_insn (); insn; insn = PREV_INSN (insn)) + { + if (NOTE_P (insn)) + { + if (NOTE_KIND (insn) == NOTE_INSN_EPILOGUE_BEG) + note = insn; + } + else if (contains (insn, &epilogue)) + { + last = insn; + if (--len == 0) + break; + } + } + + if (last) + { + /* Find the epilogue-begin note if we haven't already, and + move it to just before the first epilogue insn. */ + if (note == 0) + { + for (note = insn; (note = PREV_INSN (note));) + if (NOTE_P (note) + && NOTE_KIND (note) == NOTE_INSN_EPILOGUE_BEG) + break; + } + + if (PREV_INSN (last) != note) + reorder_insns (note, note, PREV_INSN (last)); + } + } +#endif /* HAVE_prologue or HAVE_epilogue */ +} + +/* Returns the name of the current function. */ +const char * +current_function_name (void) +{ + return lang_hooks.decl_printable_name (cfun->decl, 2); +} + +/* Returns the raw (mangled) name of the current function. */ +const char * +current_function_assembler_name (void) +{ + return IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (cfun->decl)); +} + + +static unsigned int +rest_of_handle_check_leaf_regs (void) +{ +#ifdef LEAF_REGISTERS + current_function_uses_only_leaf_regs + = optimize > 0 && only_leaf_regs_used () && leaf_function_p (); +#endif + return 0; +} + +/* Insert a TYPE into the used types hash table of CFUN. */ +static void +used_types_insert_helper (tree type, struct function *func) +{ + if (type != NULL && func != NULL) + { + void **slot; + + if (func->used_types_hash == NULL) + func->used_types_hash = htab_create_ggc (37, htab_hash_pointer, + htab_eq_pointer, NULL); + slot = htab_find_slot (func->used_types_hash, type, INSERT); + if (*slot == NULL) + *slot = type; + } +} + +/* Given a type, insert it into the used hash table in cfun. */ +void +used_types_insert (tree t) +{ + while (POINTER_TYPE_P (t) || TREE_CODE (t) == ARRAY_TYPE) + t = TREE_TYPE (t); + t = TYPE_MAIN_VARIANT (t); + if (debug_info_level > DINFO_LEVEL_NONE) + used_types_insert_helper (t, cfun); +} + +struct rtl_opt_pass pass_leaf_regs = +{ + { + RTL_PASS, + NULL, /* name */ + NULL, /* gate */ + rest_of_handle_check_leaf_regs, /* execute */ + NULL, /* sub */ + NULL, /* next */ + 0, /* static_pass_number */ + 0, /* tv_id */ + 0, /* properties_required */ + 0, /* properties_provided */ + 0, /* properties_destroyed */ + 0, /* todo_flags_start */ + 0 /* todo_flags_finish */ + } +}; + +static unsigned int +rest_of_handle_thread_prologue_and_epilogue (void) +{ + if (optimize) + cleanup_cfg (CLEANUP_EXPENSIVE); + /* On some machines, the prologue and epilogue code, or parts thereof, + can be represented as RTL. Doing so lets us schedule insns between + it and the rest of the code and also allows delayed branch + scheduling to operate in the epilogue. */ + + thread_prologue_and_epilogue_insns (); + return 0; +} + +struct rtl_opt_pass pass_thread_prologue_and_epilogue = +{ + { + RTL_PASS, + "pro_and_epilogue", /* name */ + NULL, /* gate */ + rest_of_handle_thread_prologue_and_epilogue, /* execute */ + NULL, /* sub */ + NULL, /* next */ + 0, /* static_pass_number */ + TV_THREAD_PROLOGUE_AND_EPILOGUE, /* tv_id */ + 0, /* properties_required */ + 0, /* properties_provided */ + 0, /* properties_destroyed */ + TODO_verify_flow, /* todo_flags_start */ + TODO_dump_func | + TODO_df_verify | + TODO_df_finish | TODO_verify_rtl_sharing | + TODO_ggc_collect /* todo_flags_finish */ + } +}; + + +/* This mini-pass fixes fall-out from SSA in asm statements that have + in-out constraints. Say you start with + + orig = inout; + asm ("": "+mr" (inout)); + use (orig); + + which is transformed very early to use explicit output and match operands: + + orig = inout; + asm ("": "=mr" (inout) : "0" (inout)); + use (orig); + + Or, after SSA and copyprop, + + asm ("": "=mr" (inout_2) : "0" (inout_1)); + use (inout_1); + + Clearly inout_2 and inout_1 can't be coalesced easily anymore, as + they represent two separate values, so they will get different pseudo + registers during expansion. Then, since the two operands need to match + per the constraints, but use different pseudo registers, reload can + only register a reload for these operands. But reloads can only be + satisfied by hardregs, not by memory, so we need a register for this + reload, just because we are presented with non-matching operands. + So, even though we allow memory for this operand, no memory can be + used for it, just because the two operands don't match. This can + cause reload failures on register-starved targets. + + So it's a symptom of reload not being able to use memory for reloads + or, alternatively it's also a symptom of both operands not coming into + reload as matching (in which case the pseudo could go to memory just + fine, as the alternative allows it, and no reload would be necessary). + We fix the latter problem here, by transforming + + asm ("": "=mr" (inout_2) : "0" (inout_1)); + + back to + + inout_2 = inout_1; + asm ("": "=mr" (inout_2) : "0" (inout_2)); */ + +static void +match_asm_constraints_1 (rtx insn, rtx *p_sets, int noutputs) +{ + int i; + bool changed = false; + rtx op = SET_SRC (p_sets[0]); + int ninputs = ASM_OPERANDS_INPUT_LENGTH (op); + rtvec inputs = ASM_OPERANDS_INPUT_VEC (op); + bool *output_matched = XALLOCAVEC (bool, noutputs); + + memset (output_matched, 0, noutputs * sizeof (bool)); + for (i = 0; i < ninputs; i++) + { + rtx input, output, insns; + const char *constraint = ASM_OPERANDS_INPUT_CONSTRAINT (op, i); + char *end; + int match, j; + + if (*constraint == '%') + constraint++; + + match = strtoul (constraint, &end, 10); + if (end == constraint) + continue; + + gcc_assert (match < noutputs); + output = SET_DEST (p_sets[match]); + input = RTVEC_ELT (inputs, i); + /* Only do the transformation for pseudos. */ + if (! REG_P (output) + || rtx_equal_p (output, input) + || (GET_MODE (input) != VOIDmode + && GET_MODE (input) != GET_MODE (output))) + continue; + + /* We can't do anything if the output is also used as input, + as we're going to overwrite it. */ + for (j = 0; j < ninputs; j++) + if (reg_overlap_mentioned_p (output, RTVEC_ELT (inputs, j))) + break; + if (j != ninputs) + continue; + + /* Avoid changing the same input several times. For + asm ("" : "=mr" (out1), "=mr" (out2) : "0" (in), "1" (in)); + only change in once (to out1), rather than changing it + first to out1 and afterwards to out2. */ + if (i > 0) + { + for (j = 0; j < noutputs; j++) + if (output_matched[j] && input == SET_DEST (p_sets[j])) + break; + if (j != noutputs) + continue; + } + output_matched[match] = true; + + start_sequence (); + emit_move_insn (output, input); + insns = get_insns (); + end_sequence (); + emit_insn_before (insns, insn); + + /* Now replace all mentions of the input with output. We can't + just replace the occurrence in inputs[i], as the register might + also be used in some other input (or even in an address of an + output), which would mean possibly increasing the number of + inputs by one (namely 'output' in addition), which might pose + a too complicated problem for reload to solve. E.g. this situation: + + asm ("" : "=r" (output), "=m" (input) : "0" (input)) + + Here 'input' is used in two occurrences as input (once for the + input operand, once for the address in the second output operand). + If we would replace only the occurrence of the input operand (to + make the matching) we would be left with this: + + output = input + asm ("" : "=r" (output), "=m" (input) : "0" (output)) + + Now we suddenly have two different input values (containing the same + value, but different pseudos) where we formerly had only one. + With more complicated asms this might lead to reload failures + which wouldn't have happen without this pass. So, iterate over + all operands and replace all occurrences of the register used. */ + for (j = 0; j < noutputs; j++) + if (!rtx_equal_p (SET_DEST (p_sets[j]), input) + && reg_overlap_mentioned_p (input, SET_DEST (p_sets[j]))) + SET_DEST (p_sets[j]) = replace_rtx (SET_DEST (p_sets[j]), + input, output); + for (j = 0; j < ninputs; j++) + if (reg_overlap_mentioned_p (input, RTVEC_ELT (inputs, j))) + RTVEC_ELT (inputs, j) = replace_rtx (RTVEC_ELT (inputs, j), + input, output); + + changed = true; + } + + if (changed) + df_insn_rescan (insn); +} + +static unsigned +rest_of_match_asm_constraints (void) +{ + basic_block bb; + rtx insn, pat, *p_sets; + int noutputs; + + if (!crtl->has_asm_statement) + return 0; + + df_set_flags (DF_DEFER_INSN_RESCAN); + FOR_EACH_BB (bb) + { + FOR_BB_INSNS (bb, insn) + { + if (!INSN_P (insn)) + continue; + + pat = PATTERN (insn); + if (GET_CODE (pat) == PARALLEL) + p_sets = &XVECEXP (pat, 0, 0), noutputs = XVECLEN (pat, 0); + else if (GET_CODE (pat) == SET) + p_sets = &PATTERN (insn), noutputs = 1; + else + continue; + + if (GET_CODE (*p_sets) == SET + && GET_CODE (SET_SRC (*p_sets)) == ASM_OPERANDS) + match_asm_constraints_1 (insn, p_sets, noutputs); + } + } + + return TODO_df_finish; +} + +struct rtl_opt_pass pass_match_asm_constraints = +{ + { + RTL_PASS, + "asmcons", /* name */ + NULL, /* gate */ + rest_of_match_asm_constraints, /* execute */ + NULL, /* sub */ + NULL, /* next */ + 0, /* static_pass_number */ + 0, /* tv_id */ + 0, /* properties_required */ + 0, /* properties_provided */ + 0, /* properties_destroyed */ + 0, /* todo_flags_start */ + TODO_dump_func /* todo_flags_finish */ + } +}; + + +#include "gt-function.h"