CbC/CbC_llvm: lib/CodeGen/ShrinkWrap.cpp annotate

annotate lib/CodeGen/ShrinkWrap.cpp @ 121:803732b1fca8

LLVM 5.0

author	kono
date	Fri, 27 Oct 2017 17:07:41 +0900
parents	1172e4bd9c6f
children	3a76565eade5

rev	line source
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	1 //===- ShrinkWrap.cpp - Compute safe point for prolog/epilog insertion ----===//
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	2 //
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	3 // The LLVM Compiler Infrastructure
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	4 //
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	5 // This file is distributed under the University of Illinois Open Source
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	6 // License. See LICENSE.TXT for details.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	7 //
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	8 //===----------------------------------------------------------------------===//
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	9 //
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	10 // This pass looks for safe point where the prologue and epilogue can be
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	11 // inserted.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	12 // The safe point for the prologue (resp. epilogue) is called Save
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	13 // (resp. Restore).
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	14 // A point is safe for prologue (resp. epilogue) if and only if
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	15 // it 1) dominates (resp. post-dominates) all the frame related operations and
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	16 // between 2) two executions of the Save (resp. Restore) point there is an
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	17 // execution of the Restore (resp. Save) point.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	18 //
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	19 // For instance, the following points are safe:
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	20 // for (int i = 0; i < 10; ++i) {
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	21 // Save
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	22 // ...
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	23 // Restore
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	24 // }
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	25 // Indeed, the execution looks like Save -> Restore -> Save -> Restore ...
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	26 // And the following points are not:
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	27 // for (int i = 0; i < 10; ++i) {
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	28 // Save
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	29 // ...
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	30 // }
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	31 // for (int i = 0; i < 10; ++i) {
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	32 // ...
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	33 // Restore
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	34 // }
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	35 // Indeed, the execution looks like Save -> Save -> ... -> Restore -> Restore.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	36 //
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	37 // This pass also ensures that the safe points are 3) cheaper than the regular
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	38 // entry and exits blocks.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	39 //
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	40 // Property #1 is ensured via the use of MachineDominatorTree and
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	41 // MachinePostDominatorTree.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	42 // Property #2 is ensured via property #1 and MachineLoopInfo, i.e., both
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	43 // points must be in the same loop.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	44 // Property #3 is ensured via the MachineBlockFrequencyInfo.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	45 //
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	46 // If this pass found points matching all these properties, then
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	47 // MachineFrameInfo is updated with this information.
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	48 //
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	49 //===----------------------------------------------------------------------===//
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	50
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	51 #include "llvm/ADT/BitVector.h"
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	52 #include "llvm/ADT/PostOrderIterator.h"
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	53 #include "llvm/ADT/SetVector.h"
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	54 #include "llvm/ADT/SmallVector.h"
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	55 #include "llvm/ADT/Statistic.h"
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	56 #include "llvm/CodeGen/MachineBasicBlock.h"
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	57 #include "llvm/CodeGen/MachineBlockFrequencyInfo.h"
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	58 #include "llvm/CodeGen/MachineDominators.h"
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	59 #include "llvm/CodeGen/MachineFunction.h"
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	60 #include "llvm/CodeGen/MachineFunctionPass.h"
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	61 #include "llvm/CodeGen/MachineFrameInfo.h"
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	62 #include "llvm/CodeGen/MachineInstr.h"
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	63 #include "llvm/CodeGen/MachineLoopInfo.h"
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	64 #include "llvm/CodeGen/MachineOperand.h"
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	65 #include "llvm/CodeGen/MachinePostDominators.h"
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	66 #include "llvm/CodeGen/RegisterClassInfo.h"
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	67 #include "llvm/CodeGen/RegisterScavenging.h"
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	68 #include "llvm/IR/Attributes.h"
803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	69 #include "llvm/IR/Function.h"
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	70 #include "llvm/MC/MCAsmInfo.h"
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	71 #include "llvm/Pass.h"
803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	72 #include "llvm/Support/CommandLine.h"
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	73 #include "llvm/Support/Debug.h"
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	74 #include "llvm/Support/ErrorHandling.h"
803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	75 #include "llvm/Support/raw_ostream.h"
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	76 #include "llvm/Target/TargetFrameLowering.h"
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	77 #include "llvm/Target/TargetInstrInfo.h"
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	78 #include "llvm/Target/TargetMachine.h"
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	79 #include "llvm/Target/TargetRegisterInfo.h"
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	80 #include "llvm/Target/TargetSubtargetInfo.h"
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	81 #include <cassert>
803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	82 #include <cstdint>
803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	83 #include <memory>
803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	84
803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	85 using namespace llvm;
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	86
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	87 #define DEBUG_TYPE "shrink-wrap"
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	88
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	89 STATISTIC(NumFunc, "Number of functions");
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	90 STATISTIC(NumCandidates, "Number of shrink-wrapping candidates");
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	91 STATISTIC(NumCandidatesDropped,
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	92 "Number of shrink-wrapping candidates dropped because of frequency");
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	93
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	94 static cl::opt<cl::boolOrDefault>
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	95 EnableShrinkWrapOpt("enable-shrink-wrap", cl::Hidden,
803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	96 cl::desc("enable the shrink-wrapping pass"));
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	97
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	98 namespace {
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	99
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	100 /// \brief Class to determine where the safe point to insert the
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	101 /// prologue and epilogue are.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	102 /// Unlike the paper from Fred C. Chow, PLDI'88, that introduces the
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	103 /// shrink-wrapping term for prologue/epilogue placement, this pass
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	104 /// does not rely on expensive data-flow analysis. Instead we use the
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	105 /// dominance properties and loop information to decide which point
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	106 /// are safe for such insertion.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	107 class ShrinkWrap : public MachineFunctionPass {
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	108 /// Hold callee-saved information.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	109 RegisterClassInfo RCI;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	110 MachineDominatorTree *MDT;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	111 MachinePostDominatorTree *MPDT;
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	112
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	113 /// Current safe point found for the prologue.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	114 /// The prologue will be inserted before the first instruction
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	115 /// in this basic block.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	116 MachineBasicBlock *Save;
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	117
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	118 /// Current safe point found for the epilogue.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	119 /// The epilogue will be inserted before the first terminator instruction
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	120 /// in this basic block.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	121 MachineBasicBlock *Restore;
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	122
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	123 /// Hold the information of the basic block frequency.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	124 /// Use to check the profitability of the new points.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	125 MachineBlockFrequencyInfo *MBFI;
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	126
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	127 /// Hold the loop information. Used to determine if Save and Restore
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	128 /// are in the same loop.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	129 MachineLoopInfo *MLI;
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	130
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	131 /// Frequency of the Entry block.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	132 uint64_t EntryFreq;
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	133
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	134 /// Current opcode for frame setup.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	135 unsigned FrameSetupOpcode;
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	136
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	137 /// Current opcode for frame destroy.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	138 unsigned FrameDestroyOpcode;
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	139
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	140 /// Entry block.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	141 const MachineBasicBlock *Entry;
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	142
803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	143 using SetOfRegs = SmallSetVector<unsigned, 16>;
803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	144
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	145 /// Registers that need to be saved for the current function.
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	146 mutable SetOfRegs CurrentCSRs;
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	147
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	148 /// Current MachineFunction.
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	149 MachineFunction *MachineFunc;
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	150
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	151 /// \brief Check if \p MI uses or defines a callee-saved register or
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	152 /// a frame index. If this is the case, this means \p MI must happen
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	153 /// after Save and before Restore.
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	154 bool useOrDefCSROrFI(const MachineInstr &MI, RegScavenger *RS) const;
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	155
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	156 const SetOfRegs &getCurrentCSRs(RegScavenger *RS) const {
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	157 if (CurrentCSRs.empty()) {
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	158 BitVector SavedRegs;
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	159 const TargetFrameLowering *TFI =
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	160 MachineFunc->getSubtarget().getFrameLowering();
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	161
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	162 TFI->determineCalleeSaves(*MachineFunc, SavedRegs, RS);
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	163
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	164 for (int Reg = SavedRegs.find_first(); Reg != -1;
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	165 Reg = SavedRegs.find_next(Reg))
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	166 CurrentCSRs.insert((unsigned)Reg);
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	167 }
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	168 return CurrentCSRs;
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	169 }
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	170
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	171 /// \brief Update the Save and Restore points such that \p MBB is in
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	172 /// the region that is dominated by Save and post-dominated by Restore
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	173 /// and Save and Restore still match the safe point definition.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	174 /// Such point may not exist and Save and/or Restore may be null after
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	175 /// this call.
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	176 void updateSaveRestorePoints(MachineBasicBlock &MBB, RegScavenger *RS);
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	177
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	178 /// \brief Initialize the pass for \p MF.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	179 void init(MachineFunction &MF) {
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	180 RCI.runOnMachineFunction(MF);
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	181 MDT = &getAnalysis<MachineDominatorTree>();
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	182 MPDT = &getAnalysis<MachinePostDominatorTree>();
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	183 Save = nullptr;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	184 Restore = nullptr;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	185 MBFI = &getAnalysis<MachineBlockFrequencyInfo>();
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	186 MLI = &getAnalysis<MachineLoopInfo>();
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	187 EntryFreq = MBFI->getEntryFreq();
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	188 const TargetInstrInfo &TII = *MF.getSubtarget().getInstrInfo();
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	189 FrameSetupOpcode = TII.getCallFrameSetupOpcode();
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	190 FrameDestroyOpcode = TII.getCallFrameDestroyOpcode();
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	191 Entry = &MF.front();
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	192 CurrentCSRs.clear();
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	193 MachineFunc = &MF;
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	194
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	195 ++NumFunc;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	196 }
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	197
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	198 /// Check whether or not Save and Restore points are still interesting for
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	199 /// shrink-wrapping.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	200 bool ArePointsInteresting() const { return Save != Entry && Save && Restore; }
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	201
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	202 /// \brief Check if shrink wrapping is enabled for this target and function.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	203 static bool isShrinkWrapEnabled(const MachineFunction &MF);
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	204
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	205 public:
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	206 static char ID;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	207
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	208 ShrinkWrap() : MachineFunctionPass(ID) {
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	209 initializeShrinkWrapPass(*PassRegistry::getPassRegistry());
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	210 }
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	211
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	212 void getAnalysisUsage(AnalysisUsage &AU) const override {
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	213 AU.setPreservesAll();
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	214 AU.addRequired<MachineBlockFrequencyInfo>();
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	215 AU.addRequired<MachineDominatorTree>();
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	216 AU.addRequired<MachinePostDominatorTree>();
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	217 AU.addRequired<MachineLoopInfo>();
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	218 MachineFunctionPass::getAnalysisUsage(AU);
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	219 }
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	220
120 1172e4bd9c6f update 4.0.0 mir3636 parents: 100 diff changeset	221 StringRef getPassName() const override { return "Shrink Wrapping analysis"; }
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	222
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	223 /// \brief Perform the shrink-wrapping analysis and update
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	224 /// the MachineFrameInfo attached to \p MF with the results.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	225 bool runOnMachineFunction(MachineFunction &MF) override;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	226 };
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	227
803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	228 } // end anonymous namespace
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	229
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	230 char ShrinkWrap::ID = 0;
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	231
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	232 char &llvm::ShrinkWrapID = ShrinkWrap::ID;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	233
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	234 INITIALIZE_PASS_BEGIN(ShrinkWrap, DEBUG_TYPE, "Shrink Wrap Pass", false, false)
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	235 INITIALIZE_PASS_DEPENDENCY(MachineBlockFrequencyInfo)
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	236 INITIALIZE_PASS_DEPENDENCY(MachineDominatorTree)
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	237 INITIALIZE_PASS_DEPENDENCY(MachinePostDominatorTree)
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	238 INITIALIZE_PASS_DEPENDENCY(MachineLoopInfo)
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	239 INITIALIZE_PASS_END(ShrinkWrap, DEBUG_TYPE, "Shrink Wrap Pass", false, false)
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	240
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	241 bool ShrinkWrap::useOrDefCSROrFI(const MachineInstr &MI,
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	242 RegScavenger *RS) const {
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	243 if (MI.getOpcode() == FrameSetupOpcode \|\|
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	244 MI.getOpcode() == FrameDestroyOpcode) {
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	245 DEBUG(dbgs() << "Frame instruction: " << MI << '\n');
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	246 return true;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	247 }
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	248 for (const MachineOperand &MO : MI.operands()) {
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	249 bool UseOrDefCSR = false;
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	250 if (MO.isReg()) {
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	251 unsigned PhysReg = MO.getReg();
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	252 if (!PhysReg)
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	253 continue;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	254 assert(TargetRegisterInfo::isPhysicalRegister(PhysReg) &&
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	255 "Unallocated register?!");
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	256 UseOrDefCSR = RCI.getLastCalleeSavedAlias(PhysReg);
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	257 } else if (MO.isRegMask()) {
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	258 // Check if this regmask clobbers any of the CSRs.
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	259 for (unsigned Reg : getCurrentCSRs(RS)) {
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	260 if (MO.clobbersPhysReg(Reg)) {
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	261 UseOrDefCSR = true;
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	262 break;
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	263 }
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	264 }
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	265 }
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	266 if (UseOrDefCSR \|\| MO.isFI()) {
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	267 DEBUG(dbgs() << "Use or define CSR(" << UseOrDefCSR << ") or FI("
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	268 << MO.isFI() << "): " << MI << '\n');
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	269 return true;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	270 }
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	271 }
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	272 return false;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	273 }
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	274
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	275 /// \brief Helper function to find the immediate (post) dominator.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	276 template <typename ListOfBBs, typename DominanceAnalysis>
120 1172e4bd9c6f update 4.0.0 mir3636 parents: 100 diff changeset	277 static MachineBasicBlock *FindIDom(MachineBasicBlock &Block, ListOfBBs BBs,
1172e4bd9c6f update 4.0.0 mir3636 parents: 100 diff changeset	278 DominanceAnalysis &Dom) {
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	279 MachineBasicBlock *IDom = &Block;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	280 for (MachineBasicBlock *BB : BBs) {
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	281 IDom = Dom.findNearestCommonDominator(IDom, BB);
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	282 if (!IDom)
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	283 break;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	284 }
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	285 if (IDom == &Block)
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	286 return nullptr;
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	287 return IDom;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	288 }
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	289
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	290 void ShrinkWrap::updateSaveRestorePoints(MachineBasicBlock &MBB,
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	291 RegScavenger *RS) {
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	292 // Get rid of the easy cases first.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	293 if (!Save)
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	294 Save = &MBB;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	295 else
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	296 Save = MDT->findNearestCommonDominator(Save, &MBB);
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	297
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	298 if (!Save) {
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	299 DEBUG(dbgs() << "Found a block that is not reachable from Entry\n");
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	300 return;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	301 }
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	302
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	303 if (!Restore)
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	304 Restore = &MBB;
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	305 else if (MPDT->getNode(&MBB)) // If the block is not in the post dom tree, it
803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	306 // means the block never returns. If that's the
803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	307 // case, we don't want to call
803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	308 // `findNearestCommonDominator`, which will
803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	309 // return `Restore`.
803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	310 Restore = MPDT->findNearestCommonDominator(Restore, &MBB);
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	311 else
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	312 Restore = nullptr; // Abort, we can't find a restore point in this case.
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	313
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	314 // Make sure we would be able to insert the restore code before the
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	315 // terminator.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	316 if (Restore == &MBB) {
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	317 for (const MachineInstr &Terminator : MBB.terminators()) {
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	318 if (!useOrDefCSROrFI(Terminator, RS))
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	319 continue;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	320 // One of the terminator needs to happen before the restore point.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	321 if (MBB.succ_empty()) {
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	322 Restore = nullptr; // Abort, we can't find a restore point in this case.
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	323 break;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	324 }
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	325 // Look for a restore point that post-dominates all the successors.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	326 // The immediate post-dominator is what we are looking for.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	327 Restore = FindIDom<>(Restore, Restore->successors(), MPDT);
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	328 break;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	329 }
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	330 }
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	331
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	332 if (!Restore) {
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	333 DEBUG(dbgs() << "Restore point needs to be spanned on several blocks\n");
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	334 return;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	335 }
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	336
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	337 // Make sure Save and Restore are suitable for shrink-wrapping:
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	338 // 1. all path from Save needs to lead to Restore before exiting.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	339 // 2. all path to Restore needs to go through Save from Entry.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	340 // We achieve that by making sure that:
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	341 // A. Save dominates Restore.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	342 // B. Restore post-dominates Save.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	343 // C. Save and Restore are in the same loop.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	344 bool SaveDominatesRestore = false;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	345 bool RestorePostDominatesSave = false;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	346 while (Save && Restore &&
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	347 (!(SaveDominatesRestore = MDT->dominates(Save, Restore)) \|\|
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	348 !(RestorePostDominatesSave = MPDT->dominates(Restore, Save)) \|\|
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	349 // Post-dominance is not enough in loops to ensure that all uses/defs
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	350 // are after the prologue and before the epilogue at runtime.
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	351 // E.g.,
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	352 // while(1) {
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	353 // Save
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	354 // Restore
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	355 // if (...)
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	356 // break;
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	357 // use/def CSRs
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	358 // }
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	359 // All the uses/defs of CSRs are dominated by Save and post-dominated
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	360 // by Restore. However, the CSRs uses are still reachable after
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	361 // Restore and before Save are executed.
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	362 //
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	363 // For now, just push the restore/save points outside of loops.
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	364 // FIXME: Refine the criteria to still find interesting cases
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	365 // for loops.
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	366 MLI->getLoopFor(Save) \|\| MLI->getLoopFor(Restore))) {
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	367 // Fix (A).
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	368 if (!SaveDominatesRestore) {
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	369 Save = MDT->findNearestCommonDominator(Save, Restore);
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	370 continue;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	371 }
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	372 // Fix (B).
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	373 if (!RestorePostDominatesSave)
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	374 Restore = MPDT->findNearestCommonDominator(Restore, Save);
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	375
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	376 // Fix (C).
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	377 if (Save && Restore &&
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	378 (MLI->getLoopFor(Save) \|\| MLI->getLoopFor(Restore))) {
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	379 if (MLI->getLoopDepth(Save) > MLI->getLoopDepth(Restore)) {
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	380 // Push Save outside of this loop if immediate dominator is different
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	381 // from save block. If immediate dominator is not different, bail out.
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	382 Save = FindIDom<>(Save, Save->predecessors(), MDT);
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	383 if (!Save)
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	384 break;
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	385 } else {
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	386 // If the loop does not exit, there is no point in looking
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	387 // for a post-dominator outside the loop.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	388 SmallVector<MachineBasicBlock*, 4> ExitBlocks;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	389 MLI->getLoopFor(Restore)->getExitingBlocks(ExitBlocks);
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	390 // Push Restore outside of this loop.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	391 // Look for the immediate post-dominator of the loop exits.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	392 MachineBasicBlock *IPdom = Restore;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	393 for (MachineBasicBlock *LoopExitBB: ExitBlocks) {
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	394 IPdom = FindIDom<>(IPdom, LoopExitBB->successors(), MPDT);
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	395 if (!IPdom)
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	396 break;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	397 }
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	398 // If the immediate post-dominator is not in a less nested loop,
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	399 // then we are stuck in a program with an infinite loop.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	400 // In that case, we will not find a safe point, hence, bail out.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	401 if (IPdom && MLI->getLoopDepth(IPdom) < MLI->getLoopDepth(Restore))
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	402 Restore = IPdom;
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	403 else {
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	404 Restore = nullptr;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	405 break;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	406 }
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	407 }
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	408 }
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	409 }
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	410 }
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	411
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	412 /// Check whether the edge (\p SrcBB, \p DestBB) is a backedge according to MLI.
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	413 /// I.e., check if it exists a loop that contains SrcBB and where DestBB is the
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	414 /// loop header.
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	415 static bool isProperBackedge(const MachineLoopInfo &MLI,
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	416 const MachineBasicBlock *SrcBB,
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	417 const MachineBasicBlock *DestBB) {
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	418 for (const MachineLoop *Loop = MLI.getLoopFor(SrcBB); Loop;
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	419 Loop = Loop->getParentLoop()) {
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	420 if (Loop->getHeader() == DestBB)
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	421 return true;
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	422 }
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	423 return false;
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	424 }
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	425
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	426 /// Check if the CFG of \p MF is irreducible.
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	427 static bool isIrreducibleCFG(const MachineFunction &MF,
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	428 const MachineLoopInfo &MLI) {
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	429 const MachineBasicBlock Entry = &MF.begin();
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	430 ReversePostOrderTraversal<const MachineBasicBlock *> RPOT(Entry);
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	431 BitVector VisitedBB(MF.getNumBlockIDs());
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	432 for (const MachineBasicBlock *MBB : RPOT) {
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	433 VisitedBB.set(MBB->getNumber());
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	434 for (const MachineBasicBlock *SuccBB : MBB->successors()) {
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	435 if (!VisitedBB.test(SuccBB->getNumber()))
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	436 continue;
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	437 // We already visited SuccBB, thus MBB->SuccBB must be a backedge.
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	438 // Check that the head matches what we have in the loop information.
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	439 // Otherwise, we have an irreducible graph.
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	440 if (!isProperBackedge(MLI, MBB, SuccBB))
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	441 return true;
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	442 }
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	443 }
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	444 return false;
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	445 }
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	446
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	447 bool ShrinkWrap::runOnMachineFunction(MachineFunction &MF) {
121 803732b1fca8 LLVM 5.0 kono parents: 120 diff changeset	448 if (skipFunction(*MF.getFunction()) \|\| MF.empty() \|\| !isShrinkWrapEnabled(MF))
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	449 return false;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	450
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	451 DEBUG(dbgs() << "**** Analysing " << MF.getName() << '\n');
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	452
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	453 init(MF);
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	454
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	455 if (isIrreducibleCFG(MF, *MLI)) {
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	456 // If MF is irreducible, a block may be in a loop without
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	457 // MachineLoopInfo reporting it. I.e., we may use the
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	458 // post-dominance property in loops, which lead to incorrect
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	459 // results. Moreover, we may miss that the prologue and
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	460 // epilogue are not in the same loop, leading to unbalanced
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	461 // construction/deconstruction of the stack frame.
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	462 DEBUG(dbgs() << "Irreducible CFGs are not supported yet\n");
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	463 return false;
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	464 }
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	465
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	466 const TargetRegisterInfo *TRI = MF.getSubtarget().getRegisterInfo();
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	467 std::unique_ptr<RegScavenger> RS(
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	468 TRI->requiresRegisterScavenging(MF) ? new RegScavenger() : nullptr);
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	469
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	470 for (MachineBasicBlock &MBB : MF) {
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	471 DEBUG(dbgs() << "Look into: " << MBB.getNumber() << ' ' << MBB.getName()
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	472 << '\n');
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	473
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	474 if (MBB.isEHFuncletEntry()) {
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	475 DEBUG(dbgs() << "EH Funclets are not supported yet.\n");
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	476 return false;
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	477 }
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	478
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	479 for (const MachineInstr &MI : MBB) {
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	480 if (!useOrDefCSROrFI(MI, RS.get()))
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	481 continue;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	482 // Save (resp. restore) point must dominate (resp. post dominate)
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	483 // MI. Look for the proper basic block for those.
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	484 updateSaveRestorePoints(MBB, RS.get());
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	485 // If we are at a point where we cannot improve the placement of
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	486 // save/restore instructions, just give up.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	487 if (!ArePointsInteresting()) {
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	488 DEBUG(dbgs() << "No Shrink wrap candidate found\n");
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	489 return false;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	490 }
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	491 // No need to look for other instructions, this basic block
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	492 // will already be part of the handled region.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	493 break;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	494 }
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	495 }
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	496 if (!ArePointsInteresting()) {
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	497 // If the points are not interesting at this point, then they must be null
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	498 // because it means we did not encounter any frame/CSR related code.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	499 // Otherwise, we would have returned from the previous loop.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	500 assert(!Save && !Restore && "We miss a shrink-wrap opportunity?!");
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	501 DEBUG(dbgs() << "Nothing to shrink-wrap\n");
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	502 return false;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	503 }
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	504
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	505 DEBUG(dbgs() << "\n Results \nFrequency of the Entry: " << EntryFreq
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	506 << '\n');
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	507
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	508 const TargetFrameLowering *TFI = MF.getSubtarget().getFrameLowering();
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	509 do {
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	510 DEBUG(dbgs() << "Shrink wrap candidates (#, Name, Freq):\nSave: "
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	511 << Save->getNumber() << ' ' << Save->getName() << ' '
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	512 << MBFI->getBlockFreq(Save).getFrequency() << "\nRestore: "
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	513 << Restore->getNumber() << ' ' << Restore->getName() << ' '
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	514 << MBFI->getBlockFreq(Restore).getFrequency() << '\n');
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	515
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	516 bool IsSaveCheap, TargetCanUseSaveAsPrologue = false;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	517 if (((IsSaveCheap = EntryFreq >= MBFI->getBlockFreq(Save).getFrequency()) &&
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	518 EntryFreq >= MBFI->getBlockFreq(Restore).getFrequency()) &&
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	519 ((TargetCanUseSaveAsPrologue = TFI->canUseAsPrologue(*Save)) &&
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	520 TFI->canUseAsEpilogue(*Restore)))
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	521 break;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	522 DEBUG(dbgs() << "New points are too expensive or invalid for the target\n");
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	523 MachineBasicBlock *NewBB;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	524 if (!IsSaveCheap \|\| !TargetCanUseSaveAsPrologue) {
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	525 Save = FindIDom<>(Save, Save->predecessors(), MDT);
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	526 if (!Save)
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	527 break;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	528 NewBB = Save;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	529 } else {
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	530 // Restore is expensive.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	531 Restore = FindIDom<>(Restore, Restore->successors(), MPDT);
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	532 if (!Restore)
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	533 break;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	534 NewBB = Restore;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	535 }
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	536 updateSaveRestorePoints(*NewBB, RS.get());
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	537 } while (Save && Restore);
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	538
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	539 if (!ArePointsInteresting()) {
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	540 ++NumCandidatesDropped;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	541 return false;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	542 }
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	543
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	544 DEBUG(dbgs() << "Final shrink wrap candidates:\nSave: " << Save->getNumber()
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	545 << ' ' << Save->getName() << "\nRestore: "
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	546 << Restore->getNumber() << ' ' << Restore->getName() << '\n');
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	547
120 1172e4bd9c6f update 4.0.0 mir3636 parents: 100 diff changeset	548 MachineFrameInfo &MFI = MF.getFrameInfo();
1172e4bd9c6f update 4.0.0 mir3636 parents: 100 diff changeset	549 MFI.setSavePoint(Save);
1172e4bd9c6f update 4.0.0 mir3636 parents: 100 diff changeset	550 MFI.setRestorePoint(Restore);
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	551 ++NumCandidates;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	552 return false;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	553 }
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	554
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	555 bool ShrinkWrap::isShrinkWrapEnabled(const MachineFunction &MF) {
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	556 const TargetFrameLowering *TFI = MF.getSubtarget().getFrameLowering();
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	557
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	558 switch (EnableShrinkWrapOpt) {
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	559 case cl::BOU_UNSET:
100 7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	560 return TFI->enableShrinkWrapping(MF) &&
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	561 // Windows with CFI has some limitations that make it impossible
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	562 // to use shrink-wrapping.
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	563 !MF.getTarget().getMCAsmInfo()->usesWindowsCFI() &&
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	564 // Sanitizers look at the value of the stack at the location
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	565 // of the crash. Since a crash can happen anywhere, the
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	566 // frame must be lowered before anything else happen for the
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	567 // sanitizers to be able to get a correct stack frame.
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	568 !(MF.getFunction()->hasFnAttribute(Attribute::SanitizeAddress) \|\|
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	569 MF.getFunction()->hasFnAttribute(Attribute::SanitizeThread) \|\|
7d135dc70f03 LLVM 3.9 Miyagi Mitsuki <e135756@ie.u-ryukyu.ac.jp> parents: 95 diff changeset	570 MF.getFunction()->hasFnAttribute(Attribute::SanitizeMemory));
95 afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	571 // If EnableShrinkWrap is set, it takes precedence on whatever the
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	572 // target sets. The rational is that we assume we want to test
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	573 // something related to shrink-wrapping.
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	574 case cl::BOU_TRUE:
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	575 return true;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	576 case cl::BOU_FALSE:
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	577 return false;
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	578 }
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	579 llvm_unreachable("Invalid shrink-wrapping state");
afa8332a0e37 LLVM 3.8 Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> parents: diff changeset	580 }

Mercurial > hg > CbC > CbC_llvm

annotate lib/CodeGen/ShrinkWrap.cpp @ 121:803732b1fca8