//===-- llvm/Support/Win64EH.h ---Win64 EH Constants-------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file contains constants and structures used for implementing
// exception handling on Win64 platforms. For more information, see
// http://msdn.microsoft.com/en-us/library/1eyas8tf.aspx
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_SUPPORT_WIN64EH_H
#define LLVM_SUPPORT_WIN64EH_H
#include "llvm/Support/DataTypes.h"
#include "llvm/Support/Endian.h"
namespace llvm {
namespace Win64EH {
/// UnwindOpcodes - Enumeration whose values specify a single operation in
/// the prolog of a function.
enum UnwindOpcodes {
// The following set of unwind opcodes is for x86_64. They are documented at
// https://docs.microsoft.com/en-us/cpp/build/exception-handling-x64.
// Some generic values from this set are used for other architectures too.
UOP_PushNonVol = 0,
UOP_AllocLarge,
UOP_AllocSmall,
UOP_SetFPReg,
UOP_SaveNonVol,
UOP_SaveNonVolBig,
UOP_Epilog,
UOP_SpareCode,
UOP_SaveXMM128,
UOP_SaveXMM128Big,
UOP_PushMachFrame,
// The following set of unwind opcodes is for ARM64. They are documented at
// https://docs.microsoft.com/en-us/cpp/build/arm64-exception-handling
UOP_AllocMedium,
UOP_SaveR19R20X,
UOP_SaveFPLRX,
UOP_SaveFPLR,
UOP_SaveReg,
UOP_SaveRegX,
UOP_SaveRegP,
UOP_SaveRegPX,
UOP_SaveLRPair,
UOP_SaveFReg,
UOP_SaveFRegX,
UOP_SaveFRegP,
UOP_SaveFRegPX,
UOP_SetFP,
UOP_AddFP,
UOP_Nop,
UOP_End,
UOP_SaveNext,
UOP_TrapFrame,
UOP_Context,
UOP_ClearUnwoundToCall,
UOP_PACSignLR,
UOP_SaveAnyRegI,
UOP_SaveAnyRegIP,
UOP_SaveAnyRegD,
UOP_SaveAnyRegDP,
UOP_SaveAnyRegQ,
UOP_SaveAnyRegQP,
UOP_SaveAnyRegIX,
UOP_SaveAnyRegIPX,
UOP_SaveAnyRegDX,
UOP_SaveAnyRegDPX,
UOP_SaveAnyRegQX,
UOP_SaveAnyRegQPX,
// The following set of unwind opcodes is for ARM. They are documented at
// https://docs.microsoft.com/en-us/cpp/build/arm-exception-handling
// Stack allocations use UOP_AllocSmall, UOP_AllocLarge from above, plus
// the following. AllocSmall, AllocLarge and AllocHuge represent a 16 bit
// instruction, while the WideAlloc* opcodes represent a 32 bit instruction.
// Small can represent a stack offset of 0x7f*4 (252) bytes, Medium can
// represent up to 0x3ff*4 (4092) bytes, Large up to 0xffff*4 (262140) bytes,
// and Huge up to 0xffffff*4 (67108860) bytes.
UOP_AllocHuge,
UOP_WideAllocMedium,
UOP_WideAllocLarge,
UOP_WideAllocHuge,
UOP_WideSaveRegMask,
UOP_SaveSP,
UOP_SaveRegsR4R7LR,
UOP_WideSaveRegsR4R11LR,
UOP_SaveFRegD8D15,
UOP_SaveRegMask,
UOP_SaveLR,
UOP_SaveFRegD0D15,
UOP_SaveFRegD16D31,
// Using UOP_Nop from above
UOP_WideNop,
// Using UOP_End from above
UOP_EndNop,
UOP_WideEndNop,
// A custom unspecified opcode, consisting of one or more bytes. This
// allows producing opcodes in the implementation defined/reserved range.
UOP_Custom,
};
/// UnwindCode - This union describes a single operation in a function prolog,
/// or part thereof.
union UnwindCode {
struct {
uint8_t CodeOffset;
uint8_t UnwindOpAndOpInfo;
} u;
support::ulittle16_t FrameOffset;
uint8_t getUnwindOp() const {
return u.UnwindOpAndOpInfo & 0x0F;
}
uint8_t getOpInfo() const {
return (u.UnwindOpAndOpInfo >> 4) & 0x0F;
}
};
enum {
/// UNW_ExceptionHandler - Specifies that this function has an exception
/// handler.
UNW_ExceptionHandler = 0x01,
/// UNW_TerminateHandler - Specifies that this function has a termination
/// handler.
UNW_TerminateHandler = 0x02,
/// UNW_ChainInfo - Specifies that this UnwindInfo structure is chained to
/// another one.
UNW_ChainInfo = 0x04
};
/// RuntimeFunction - An entry in the table of functions with unwind info.
struct RuntimeFunction {
support::ulittle32_t StartAddress;
support::ulittle32_t EndAddress;
support::ulittle32_t UnwindInfoOffset;
};
/// UnwindInfo - An entry in the exception table.
struct UnwindInfo {
uint8_t VersionAndFlags;
uint8_t PrologSize;
uint8_t NumCodes;
uint8_t FrameRegisterAndOffset;
UnwindCode UnwindCodes[1];
uint8_t getVersion() const {
return VersionAndFlags & 0x07;
}
uint8_t getFlags() const {
return (VersionAndFlags >> 3) & 0x1f;
}
uint8_t getFrameRegister() const {
return FrameRegisterAndOffset & 0x0f;
}
uint8_t getFrameOffset() const {
return (FrameRegisterAndOffset >> 4) & 0x0f;
}
// The data after unwindCodes depends on flags.
// If UNW_ExceptionHandler or UNW_TerminateHandler is set then follows
// the address of the language-specific exception handler.
// If UNW_ChainInfo is set then follows a RuntimeFunction which defines
// the chained unwind info.
// For more information please see MSDN at:
// http://msdn.microsoft.com/en-us/library/ddssxxy8.aspx
/// Return pointer to language specific data part of UnwindInfo.
void *getLanguageSpecificData() {
return reinterpret_cast<void *>(&UnwindCodes[(NumCodes+1) & ~1]);
}
/// Return pointer to language specific data part of UnwindInfo.
const void *getLanguageSpecificData() const {
return reinterpret_cast<const void *>(&UnwindCodes[(NumCodes + 1) & ~1]);
}
/// Return image-relative offset of language-specific exception handler.
uint32_t getLanguageSpecificHandlerOffset() const {
return *reinterpret_cast<const support::ulittle32_t *>(
getLanguageSpecificData());
}
/// Set image-relative offset of language-specific exception handler.
void setLanguageSpecificHandlerOffset(uint32_t offset) {
*reinterpret_cast<support::ulittle32_t *>(getLanguageSpecificData()) =
offset;
}
/// Return pointer to exception-specific data.
void *getExceptionData() {
return reinterpret_cast<void *>(reinterpret_cast<uint32_t *>(
getLanguageSpecificData())+1);
}
/// Return pointer to chained unwind info.
RuntimeFunction *getChainedFunctionEntry() {
return reinterpret_cast<RuntimeFunction *>(getLanguageSpecificData());
}
/// Return pointer to chained unwind info.
const RuntimeFunction *getChainedFunctionEntry() const {
return reinterpret_cast<const RuntimeFunction *>(getLanguageSpecificData());
}
};
} // End of namespace Win64EH
} // End of namespace llvm
#endif