diff lib/CodeGen/AsmPrinter/DwarfException.h @ 0:95c75e76d11b LLVM3.4

LLVM 3.4
author Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
date Thu, 12 Dec 2013 13:56:28 +0900
parents
children e4204d083e25
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lib/CodeGen/AsmPrinter/DwarfException.h	Thu Dec 12 13:56:28 2013 +0900
@@ -0,0 +1,236 @@
+//===-- DwarfException.h - Dwarf Exception Framework -----------*- C++ -*--===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains support for writing dwarf exception info into asm files.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CODEGEN_ASMPRINTER_DWARFEXCEPTION_H
+#define LLVM_CODEGEN_ASMPRINTER_DWARFEXCEPTION_H
+
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/CodeGen/AsmPrinter.h"
+#include <vector>
+
+namespace llvm {
+
+template <typename T> class SmallVectorImpl;
+struct LandingPadInfo;
+class MachineModuleInfo;
+class MachineInstr;
+class MachineFunction;
+class MCAsmInfo;
+class MCExpr;
+class MCSymbol;
+class Function;
+class ARMTargetStreamer;
+class AsmPrinter;
+
+//===----------------------------------------------------------------------===//
+/// DwarfException - Emits Dwarf exception handling directives.
+///
+class DwarfException {
+protected:
+  /// Asm - Target of Dwarf emission.
+  AsmPrinter *Asm;
+
+  /// MMI - Collected machine module information.
+  MachineModuleInfo *MMI;
+
+  /// SharedTypeIds - How many leading type ids two landing pads have in common.
+  static unsigned SharedTypeIds(const LandingPadInfo *L,
+                                const LandingPadInfo *R);
+
+  /// PadLT - Order landing pads lexicographically by type id.
+  static bool PadLT(const LandingPadInfo *L, const LandingPadInfo *R);
+
+  /// PadRange - Structure holding a try-range and the associated landing pad.
+  struct PadRange {
+    // The index of the landing pad.
+    unsigned PadIndex;
+    // The index of the begin and end labels in the landing pad's label lists.
+    unsigned RangeIndex;
+  };
+
+  typedef DenseMap<MCSymbol *, PadRange> RangeMapType;
+
+  /// ActionEntry - Structure describing an entry in the actions table.
+  struct ActionEntry {
+    int ValueForTypeID; // The value to write - may not be equal to the type id.
+    int NextAction;
+    unsigned Previous;
+  };
+
+  /// CallSiteEntry - Structure describing an entry in the call-site table.
+  struct CallSiteEntry {
+    // The 'try-range' is BeginLabel .. EndLabel.
+    MCSymbol *BeginLabel; // zero indicates the start of the function.
+    MCSymbol *EndLabel;   // zero indicates the end of the function.
+
+    // The landing pad starts at PadLabel.
+    MCSymbol *PadLabel;   // zero indicates that there is no landing pad.
+    unsigned Action;
+  };
+
+  /// ComputeActionsTable - Compute the actions table and gather the first
+  /// action index for each landing pad site.
+  unsigned ComputeActionsTable(const SmallVectorImpl<const LandingPadInfo*>&LPs,
+                               SmallVectorImpl<ActionEntry> &Actions,
+                               SmallVectorImpl<unsigned> &FirstActions);
+
+  /// CallToNoUnwindFunction - Return `true' if this is a call to a function
+  /// marked `nounwind'. Return `false' otherwise.
+  bool CallToNoUnwindFunction(const MachineInstr *MI);
+
+  /// ComputeCallSiteTable - Compute the call-site table.  The entry for an
+  /// invoke has a try-range containing the call, a non-zero landing pad and an
+  /// appropriate action.  The entry for an ordinary call has a try-range
+  /// containing the call and zero for the landing pad and the action.  Calls
+  /// marked 'nounwind' have no entry and must not be contained in the try-range
+  /// of any entry - they form gaps in the table.  Entries must be ordered by
+  /// try-range address.
+  void ComputeCallSiteTable(SmallVectorImpl<CallSiteEntry> &CallSites,
+                            const RangeMapType &PadMap,
+                            const SmallVectorImpl<const LandingPadInfo *> &LPs,
+                            const SmallVectorImpl<unsigned> &FirstActions);
+
+  /// EmitExceptionTable - Emit landing pads and actions.
+  ///
+  /// The general organization of the table is complex, but the basic concepts
+  /// are easy.  First there is a header which describes the location and
+  /// organization of the three components that follow.
+  ///  1. The landing pad site information describes the range of code covered
+  ///     by the try.  In our case it's an accumulation of the ranges covered
+  ///     by the invokes in the try.  There is also a reference to the landing
+  ///     pad that handles the exception once processed.  Finally an index into
+  ///     the actions table.
+  ///  2. The action table, in our case, is composed of pairs of type ids
+  ///     and next action offset.  Starting with the action index from the
+  ///     landing pad site, each type Id is checked for a match to the current
+  ///     exception.  If it matches then the exception and type id are passed
+  ///     on to the landing pad.  Otherwise the next action is looked up.  This
+  ///     chain is terminated with a next action of zero.  If no type id is
+  ///     found the frame is unwound and handling continues.
+  ///  3. Type id table contains references to all the C++ typeinfo for all
+  ///     catches in the function.  This tables is reversed indexed base 1.
+  void EmitExceptionTable();
+
+  virtual void EmitTypeInfos(unsigned TTypeEncoding);
+
+public:
+  //===--------------------------------------------------------------------===//
+  // Main entry points.
+  //
+  DwarfException(AsmPrinter *A);
+  virtual ~DwarfException();
+
+  /// EndModule - Emit all exception information that should come after the
+  /// content.
+  virtual void EndModule();
+
+  /// BeginFunction - Gather pre-function exception information.  Assumes being
+  /// emitted immediately after the function entry point.
+  virtual void BeginFunction(const MachineFunction *MF);
+
+  /// EndFunction - Gather and emit post-function exception information.
+  virtual void EndFunction();
+};
+
+class DwarfCFIException : public DwarfException {
+  /// shouldEmitPersonality - Per-function flag to indicate if .cfi_personality
+  /// should be emitted.
+  bool shouldEmitPersonality;
+
+  /// shouldEmitLSDA - Per-function flag to indicate if .cfi_lsda
+  /// should be emitted.
+  bool shouldEmitLSDA;
+
+  /// shouldEmitMoves - Per-function flag to indicate if frame moves info
+  /// should be emitted.
+  bool shouldEmitMoves;
+
+  AsmPrinter::CFIMoveType moveTypeModule;
+
+public:
+  //===--------------------------------------------------------------------===//
+  // Main entry points.
+  //
+  DwarfCFIException(AsmPrinter *A);
+  virtual ~DwarfCFIException();
+
+  /// EndModule - Emit all exception information that should come after the
+  /// content.
+  virtual void EndModule();
+
+  /// BeginFunction - Gather pre-function exception information.  Assumes being
+  /// emitted immediately after the function entry point.
+  virtual void BeginFunction(const MachineFunction *MF);
+
+  /// EndFunction - Gather and emit post-function exception information.
+  virtual void EndFunction();
+};
+
+class ARMException : public DwarfException {
+  void EmitTypeInfos(unsigned TTypeEncoding);
+  ARMTargetStreamer &getTargetStreamer();
+
+public:
+  //===--------------------------------------------------------------------===//
+  // Main entry points.
+  //
+  ARMException(AsmPrinter *A);
+  virtual ~ARMException();
+
+  /// EndModule - Emit all exception information that should come after the
+  /// content.
+  virtual void EndModule();
+
+  /// BeginFunction - Gather pre-function exception information.  Assumes being
+  /// emitted immediately after the function entry point.
+  virtual void BeginFunction(const MachineFunction *MF);
+
+  /// EndFunction - Gather and emit post-function exception information.
+  virtual void EndFunction();
+};
+
+class Win64Exception : public DwarfException {
+  /// shouldEmitPersonality - Per-function flag to indicate if personality
+  /// info should be emitted.
+  bool shouldEmitPersonality;
+
+  /// shouldEmitLSDA - Per-function flag to indicate if the LSDA
+  /// should be emitted.
+  bool shouldEmitLSDA;
+
+  /// shouldEmitMoves - Per-function flag to indicate if frame moves info
+  /// should be emitted.
+  bool shouldEmitMoves;
+
+public:
+  //===--------------------------------------------------------------------===//
+  // Main entry points.
+  //
+  Win64Exception(AsmPrinter *A);
+  virtual ~Win64Exception();
+
+  /// EndModule - Emit all exception information that should come after the
+  /// content.
+  virtual void EndModule();
+
+  /// BeginFunction - Gather pre-function exception information.  Assumes being
+  /// emitted immediately after the function entry point.
+  virtual void BeginFunction(const MachineFunction *MF);
+
+  /// EndFunction - Gather and emit post-function exception information.
+  virtual void EndFunction();
+};
+
+} // End of namespace llvm
+
+#endif