mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2025-11-04 05:17:07 +00:00
cd52a7a381
Apparently, the style needs to be agreed upon first. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240390 91177308-0d34-0410-b5e6-96231b3b80d8
253 lines
8.5 KiB
C++
253 lines
8.5 KiB
C++
//===- lib/MC/MCWin64EH.cpp - MCWin64EH implementation --------------------===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "llvm/MC/MCWin64EH.h"
|
|
#include "llvm/ADT/Twine.h"
|
|
#include "llvm/MC/MCContext.h"
|
|
#include "llvm/MC/MCExpr.h"
|
|
#include "llvm/MC/MCObjectFileInfo.h"
|
|
#include "llvm/MC/MCSectionCOFF.h"
|
|
#include "llvm/MC/MCStreamer.h"
|
|
#include "llvm/MC/MCSymbol.h"
|
|
#include "llvm/Support/Win64EH.h"
|
|
|
|
namespace llvm {
|
|
|
|
// NOTE: All relocations generated here are 4-byte image-relative.
|
|
|
|
static uint8_t CountOfUnwindCodes(std::vector<WinEH::Instruction> &Insns) {
|
|
uint8_t Count = 0;
|
|
for (const auto &I : Insns) {
|
|
switch (static_cast<Win64EH::UnwindOpcodes>(I.Operation)) {
|
|
case Win64EH::UOP_PushNonVol:
|
|
case Win64EH::UOP_AllocSmall:
|
|
case Win64EH::UOP_SetFPReg:
|
|
case Win64EH::UOP_PushMachFrame:
|
|
Count += 1;
|
|
break;
|
|
case Win64EH::UOP_SaveNonVol:
|
|
case Win64EH::UOP_SaveXMM128:
|
|
Count += 2;
|
|
break;
|
|
case Win64EH::UOP_SaveNonVolBig:
|
|
case Win64EH::UOP_SaveXMM128Big:
|
|
Count += 3;
|
|
break;
|
|
case Win64EH::UOP_AllocLarge:
|
|
Count += (I.Offset > 512 * 1024 - 8) ? 3 : 2;
|
|
break;
|
|
}
|
|
}
|
|
return Count;
|
|
}
|
|
|
|
static void EmitAbsDifference(MCStreamer &Streamer, const MCSymbol *LHS,
|
|
const MCSymbol *RHS) {
|
|
MCContext &Context = Streamer.getContext();
|
|
const MCExpr *Diff =
|
|
MCBinaryExpr::createSub(MCSymbolRefExpr::create(LHS, Context),
|
|
MCSymbolRefExpr::create(RHS, Context), Context);
|
|
Streamer.EmitValue(Diff, 1);
|
|
}
|
|
|
|
static void EmitUnwindCode(MCStreamer &streamer, const MCSymbol *begin,
|
|
WinEH::Instruction &inst) {
|
|
uint8_t b2;
|
|
uint16_t w;
|
|
b2 = (inst.Operation & 0x0F);
|
|
switch (static_cast<Win64EH::UnwindOpcodes>(inst.Operation)) {
|
|
case Win64EH::UOP_PushNonVol:
|
|
EmitAbsDifference(streamer, inst.Label, begin);
|
|
b2 |= (inst.Register & 0x0F) << 4;
|
|
streamer.EmitIntValue(b2, 1);
|
|
break;
|
|
case Win64EH::UOP_AllocLarge:
|
|
EmitAbsDifference(streamer, inst.Label, begin);
|
|
if (inst.Offset > 512 * 1024 - 8) {
|
|
b2 |= 0x10;
|
|
streamer.EmitIntValue(b2, 1);
|
|
w = inst.Offset & 0xFFF8;
|
|
streamer.EmitIntValue(w, 2);
|
|
w = inst.Offset >> 16;
|
|
} else {
|
|
streamer.EmitIntValue(b2, 1);
|
|
w = inst.Offset >> 3;
|
|
}
|
|
streamer.EmitIntValue(w, 2);
|
|
break;
|
|
case Win64EH::UOP_AllocSmall:
|
|
b2 |= (((inst.Offset - 8) >> 3) & 0x0F) << 4;
|
|
EmitAbsDifference(streamer, inst.Label, begin);
|
|
streamer.EmitIntValue(b2, 1);
|
|
break;
|
|
case Win64EH::UOP_SetFPReg:
|
|
EmitAbsDifference(streamer, inst.Label, begin);
|
|
streamer.EmitIntValue(b2, 1);
|
|
break;
|
|
case Win64EH::UOP_SaveNonVol:
|
|
case Win64EH::UOP_SaveXMM128:
|
|
b2 |= (inst.Register & 0x0F) << 4;
|
|
EmitAbsDifference(streamer, inst.Label, begin);
|
|
streamer.EmitIntValue(b2, 1);
|
|
w = inst.Offset >> 3;
|
|
if (inst.Operation == Win64EH::UOP_SaveXMM128)
|
|
w >>= 1;
|
|
streamer.EmitIntValue(w, 2);
|
|
break;
|
|
case Win64EH::UOP_SaveNonVolBig:
|
|
case Win64EH::UOP_SaveXMM128Big:
|
|
b2 |= (inst.Register & 0x0F) << 4;
|
|
EmitAbsDifference(streamer, inst.Label, begin);
|
|
streamer.EmitIntValue(b2, 1);
|
|
if (inst.Operation == Win64EH::UOP_SaveXMM128Big)
|
|
w = inst.Offset & 0xFFF0;
|
|
else
|
|
w = inst.Offset & 0xFFF8;
|
|
streamer.EmitIntValue(w, 2);
|
|
w = inst.Offset >> 16;
|
|
streamer.EmitIntValue(w, 2);
|
|
break;
|
|
case Win64EH::UOP_PushMachFrame:
|
|
if (inst.Offset == 1)
|
|
b2 |= 0x10;
|
|
EmitAbsDifference(streamer, inst.Label, begin);
|
|
streamer.EmitIntValue(b2, 1);
|
|
break;
|
|
}
|
|
}
|
|
|
|
static void EmitSymbolRefWithOfs(MCStreamer &streamer,
|
|
const MCSymbol *Base,
|
|
const MCSymbol *Other) {
|
|
MCContext &Context = streamer.getContext();
|
|
const MCSymbolRefExpr *BaseRef = MCSymbolRefExpr::create(Base, Context);
|
|
const MCSymbolRefExpr *OtherRef = MCSymbolRefExpr::create(Other, Context);
|
|
const MCExpr *Ofs = MCBinaryExpr::createSub(OtherRef, BaseRef, Context);
|
|
const MCSymbolRefExpr *BaseRefRel = MCSymbolRefExpr::create(Base,
|
|
MCSymbolRefExpr::VK_COFF_IMGREL32,
|
|
Context);
|
|
streamer.EmitValue(MCBinaryExpr::createAdd(BaseRefRel, Ofs, Context), 4);
|
|
}
|
|
|
|
static void EmitRuntimeFunction(MCStreamer &streamer,
|
|
const WinEH::FrameInfo *info) {
|
|
MCContext &context = streamer.getContext();
|
|
|
|
streamer.EmitValueToAlignment(4);
|
|
EmitSymbolRefWithOfs(streamer, info->Function, info->Begin);
|
|
EmitSymbolRefWithOfs(streamer, info->Function, info->End);
|
|
streamer.EmitValue(MCSymbolRefExpr::create(info->Symbol,
|
|
MCSymbolRefExpr::VK_COFF_IMGREL32,
|
|
context), 4);
|
|
}
|
|
|
|
static void EmitUnwindInfo(MCStreamer &streamer, WinEH::FrameInfo *info) {
|
|
// If this UNWIND_INFO already has a symbol, it's already been emitted.
|
|
if (info->Symbol)
|
|
return;
|
|
|
|
MCContext &context = streamer.getContext();
|
|
MCSymbol *Label = context.createTempSymbol();
|
|
|
|
streamer.EmitValueToAlignment(4);
|
|
streamer.EmitLabel(Label);
|
|
info->Symbol = Label;
|
|
|
|
// Upper 3 bits are the version number (currently 1).
|
|
uint8_t flags = 0x01;
|
|
if (info->ChainedParent)
|
|
flags |= Win64EH::UNW_ChainInfo << 3;
|
|
else {
|
|
if (info->HandlesUnwind)
|
|
flags |= Win64EH::UNW_TerminateHandler << 3;
|
|
if (info->HandlesExceptions)
|
|
flags |= Win64EH::UNW_ExceptionHandler << 3;
|
|
}
|
|
streamer.EmitIntValue(flags, 1);
|
|
|
|
if (info->PrologEnd)
|
|
EmitAbsDifference(streamer, info->PrologEnd, info->Begin);
|
|
else
|
|
streamer.EmitIntValue(0, 1);
|
|
|
|
uint8_t numCodes = CountOfUnwindCodes(info->Instructions);
|
|
streamer.EmitIntValue(numCodes, 1);
|
|
|
|
uint8_t frame = 0;
|
|
if (info->LastFrameInst >= 0) {
|
|
WinEH::Instruction &frameInst = info->Instructions[info->LastFrameInst];
|
|
assert(frameInst.Operation == Win64EH::UOP_SetFPReg);
|
|
frame = (frameInst.Register & 0x0F) | (frameInst.Offset & 0xF0);
|
|
}
|
|
streamer.EmitIntValue(frame, 1);
|
|
|
|
// Emit unwind instructions (in reverse order).
|
|
uint8_t numInst = info->Instructions.size();
|
|
for (uint8_t c = 0; c < numInst; ++c) {
|
|
WinEH::Instruction inst = info->Instructions.back();
|
|
info->Instructions.pop_back();
|
|
EmitUnwindCode(streamer, info->Begin, inst);
|
|
}
|
|
|
|
// For alignment purposes, the instruction array will always have an even
|
|
// number of entries, with the final entry potentially unused (in which case
|
|
// the array will be one longer than indicated by the count of unwind codes
|
|
// field).
|
|
if (numCodes & 1) {
|
|
streamer.EmitIntValue(0, 2);
|
|
}
|
|
|
|
if (flags & (Win64EH::UNW_ChainInfo << 3))
|
|
EmitRuntimeFunction(streamer, info->ChainedParent);
|
|
else if (flags &
|
|
((Win64EH::UNW_TerminateHandler|Win64EH::UNW_ExceptionHandler) << 3))
|
|
streamer.EmitValue(MCSymbolRefExpr::create(info->ExceptionHandler,
|
|
MCSymbolRefExpr::VK_COFF_IMGREL32,
|
|
context), 4);
|
|
else if (numCodes == 0) {
|
|
// The minimum size of an UNWIND_INFO struct is 8 bytes. If we're not
|
|
// a chained unwind info, if there is no handler, and if there are fewer
|
|
// than 2 slots used in the unwind code array, we have to pad to 8 bytes.
|
|
streamer.EmitIntValue(0, 4);
|
|
}
|
|
}
|
|
|
|
namespace Win64EH {
|
|
void UnwindEmitter::Emit(MCStreamer &Streamer) const {
|
|
MCContext &Context = Streamer.getContext();
|
|
|
|
// Emit the unwind info structs first.
|
|
for (const auto &CFI : Streamer.getWinFrameInfos()) {
|
|
MCSection *XData = getXDataSection(CFI->Function, Context);
|
|
Streamer.SwitchSection(XData);
|
|
EmitUnwindInfo(Streamer, CFI);
|
|
}
|
|
|
|
// Now emit RUNTIME_FUNCTION entries.
|
|
for (const auto &CFI : Streamer.getWinFrameInfos()) {
|
|
MCSection *PData = getPDataSection(CFI->Function, Context);
|
|
Streamer.SwitchSection(PData);
|
|
EmitRuntimeFunction(Streamer, CFI);
|
|
}
|
|
}
|
|
|
|
void UnwindEmitter::EmitUnwindInfo(MCStreamer &Streamer,
|
|
WinEH::FrameInfo *info) const {
|
|
// Switch sections (the static function above is meant to be called from
|
|
// here and from Emit().
|
|
MCContext &context = Streamer.getContext();
|
|
MCSection *xdataSect = getXDataSection(info->Function, context);
|
|
Streamer.SwitchSection(xdataSect);
|
|
|
|
llvm::EmitUnwindInfo(Streamer, info);
|
|
}
|
|
}
|
|
} // End of namespace llvm
|
|
|