llvm/lib/CodeGen/AsmPrinter/WinException.h

   1 //===-- WinException.h - Windows Exception Handling ----------*- C++ -*--===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This file contains support for writing windows exception info into asm files.
  10 //
  11 //===----------------------------------------------------------------------===//
  12
  13 #ifndef LLVM_LIB_CODEGEN_ASMPRINTER_WIN64EXCEPTION_H
  14 #define LLVM_LIB_CODEGEN_ASMPRINTER_WIN64EXCEPTION_H
  15
  16 #include "EHStreamer.h"
  17 #include <vector>
  18
  19 namespace llvm {
  20 class GlobalValue;
  21 class MachineFunction;
  22 class MCExpr;
  23 class MCSection;
  24 struct WinEHFuncInfo;
  25
  26 class LLVM_LIBRARY_VISIBILITY WinException : public EHStreamer {
  27   /// Per-function flag to indicate if personality info should be emitted.
  28   bool shouldEmitPersonality = false;
  29
  30   /// Per-function flag to indicate if the LSDA should be emitted.
  31   bool shouldEmitLSDA = false;
  32
  33   /// Per-function flag to indicate if frame moves info should be emitted.
  34   bool shouldEmitMoves = false;
  35
  36   /// True if this is a 64-bit target and we should use image relative offsets.
  37   bool useImageRel32 = false;
  38
  39   /// True if we are generating exception handling on Windows for ARM64.
  40   bool isAArch64 = false;
  41
  42   /// True if we are generating exception handling on Windows for ARM (Thumb).
  43   bool isThumb = false;
  44
  45   /// Pointer to the current funclet entry BB.
  46   const MachineBasicBlock *CurrentFuncletEntry = nullptr;
  47
  48   /// The section of the last funclet start.
  49   MCSection *CurrentFuncletTextSection = nullptr;
  50
  51   /// The list of symbols to add to the ehcont section
  52   std::vector<const MCSymbol *> EHContTargets;
  53
  54   void emitCSpecificHandlerTable(const MachineFunction *MF);
  55
  56   void emitSEHActionsForRange(const WinEHFuncInfo &FuncInfo,
  57                               const MCSymbol *BeginLabel,
  58                               const MCSymbol *EndLabel, int State);
  59
  60   /// Emit the EH table data for 32-bit and 64-bit functions using
  61   /// the __CxxFrameHandler3 personality.
  62   void emitCXXFrameHandler3Table(const MachineFunction *MF);
  63
  64   /// Emit the EH table data for _except_handler3 and _except_handler4
  65   /// personality functions. These are only used on 32-bit and do not use CFI
  66   /// tables.
  67   void emitExceptHandlerTable(const MachineFunction *MF);
  68
  69   void emitCLRExceptionTable(const MachineFunction *MF);
  70
  71   void computeIP2StateTable(
  72       const MachineFunction *MF, const WinEHFuncInfo &FuncInfo,
  73       SmallVectorImpl<std::pair<const MCExpr *, int>> &IPToStateTable);
  74
  75   /// Emits the label used with llvm.eh.recoverfp, which is used by
  76   /// outlined funclets.
  77   void emitEHRegistrationOffsetLabel(const WinEHFuncInfo &FuncInfo,
  78                                      StringRef FLinkageName);
  79
  80   const MCExpr *create32bitRef(const MCSymbol *Value);
  81   const MCExpr *create32bitRef(const GlobalValue *GV);
  82   const MCExpr *getLabel(const MCSymbol *Label);
  83   const MCExpr *getLabelPlusOne(const MCSymbol *Label);
  84   const MCExpr *getOffset(const MCSymbol *OffsetOf, const MCSymbol *OffsetFrom);
  85   const MCExpr *getOffsetPlusOne(const MCSymbol *OffsetOf,
  86                                  const MCSymbol *OffsetFrom);
  87
  88   /// Gets the offset that we should use in a table for a stack object with the
  89   /// given index. For targets using CFI (Win64, etc), this is relative to the
  90   /// established SP at the end of the prologue. For targets without CFI (Win32
  91   /// only), it is relative to the frame pointer.
  92   int getFrameIndexOffset(int FrameIndex, const WinEHFuncInfo &FuncInfo);
  93
  94   void endFuncletImpl();
  95 public:
  96   //===--------------------------------------------------------------------===//
  97   // Main entry points.
  98   //
  99   WinException(AsmPrinter *A);
 100   ~WinException() override;
 101
 102   /// Emit all exception information that should come after the content.
 103   void endModule() override;
 104
 105   /// Gather pre-function exception information.  Assumes being emitted
 106   /// immediately after the function entry point.
 107   void beginFunction(const MachineFunction *MF) override;
 108
 109   void markFunctionEnd() override;
 110
 111   /// Gather and emit post-function exception information.
 112   void endFunction(const MachineFunction *) override;
 113
 114   /// Emit target-specific EH funclet machinery.
 115   void beginFunclet(const MachineBasicBlock &MBB, MCSymbol *Sym) override;
 116   void endFunclet() override;
 117 };
 118 }
 119
 120 #endif
 121