forked from OSchip/llvm-project
132 lines
4.6 KiB
C++
132 lines
4.6 KiB
C++
//===-- X86AsmPrinter.h - X86 implementation of AsmPrinter ------*- C++ -*-===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#ifndef LLVM_LIB_TARGET_X86_X86ASMPRINTER_H
|
|
#define LLVM_LIB_TARGET_X86_X86ASMPRINTER_H
|
|
|
|
#include "X86Subtarget.h"
|
|
#include "llvm/CodeGen/AsmPrinter.h"
|
|
#include "llvm/CodeGen/FaultMaps.h"
|
|
#include "llvm/CodeGen/StackMaps.h"
|
|
#include "llvm/Target/TargetMachine.h"
|
|
|
|
// Implemented in X86MCInstLower.cpp
|
|
namespace {
|
|
class X86MCInstLower;
|
|
}
|
|
|
|
namespace llvm {
|
|
class MCStreamer;
|
|
class MCSymbol;
|
|
|
|
class LLVM_LIBRARY_VISIBILITY X86AsmPrinter : public AsmPrinter {
|
|
const X86Subtarget *Subtarget;
|
|
StackMaps SM;
|
|
FaultMaps FM;
|
|
std::unique_ptr<MCCodeEmitter> CodeEmitter;
|
|
|
|
// This utility class tracks the length of a stackmap instruction's 'shadow'.
|
|
// It is used by the X86AsmPrinter to ensure that the stackmap shadow
|
|
// invariants (i.e. no other stackmaps, patchpoints, or control flow within
|
|
// the shadow) are met, while outputting a minimal number of NOPs for padding.
|
|
//
|
|
// To minimise the number of NOPs used, the shadow tracker counts the number
|
|
// of instruction bytes output since the last stackmap. Only if there are too
|
|
// few instruction bytes to cover the shadow are NOPs used for padding.
|
|
class StackMapShadowTracker {
|
|
public:
|
|
void startFunction(MachineFunction &MF) {
|
|
this->MF = &MF;
|
|
}
|
|
void count(MCInst &Inst, const MCSubtargetInfo &STI,
|
|
MCCodeEmitter *CodeEmitter);
|
|
|
|
// Called to signal the start of a shadow of RequiredSize bytes.
|
|
void reset(unsigned RequiredSize) {
|
|
RequiredShadowSize = RequiredSize;
|
|
CurrentShadowSize = 0;
|
|
InShadow = true;
|
|
}
|
|
|
|
// Called before every stackmap/patchpoint, and at the end of basic blocks,
|
|
// to emit any necessary padding-NOPs.
|
|
void emitShadowPadding(MCStreamer &OutStreamer, const MCSubtargetInfo &STI);
|
|
private:
|
|
const MachineFunction *MF;
|
|
bool InShadow = false;
|
|
|
|
// RequiredShadowSize holds the length of the shadow specified in the most
|
|
// recently encountered STACKMAP instruction.
|
|
// CurrentShadowSize counts the number of bytes encoded since the most
|
|
// recently encountered STACKMAP, stopping when that number is greater than
|
|
// or equal to RequiredShadowSize.
|
|
unsigned RequiredShadowSize = 0, CurrentShadowSize = 0;
|
|
};
|
|
|
|
StackMapShadowTracker SMShadowTracker;
|
|
|
|
// All instructions emitted by the X86AsmPrinter should use this helper
|
|
// method.
|
|
//
|
|
// This helper function invokes the SMShadowTracker on each instruction before
|
|
// outputting it to the OutStream. This allows the shadow tracker to minimise
|
|
// the number of NOPs used for stackmap padding.
|
|
void EmitAndCountInstruction(MCInst &Inst);
|
|
void LowerSTACKMAP(const MachineInstr &MI);
|
|
void LowerPATCHPOINT(const MachineInstr &MI, X86MCInstLower &MCIL);
|
|
void LowerSTATEPOINT(const MachineInstr &MI, X86MCInstLower &MCIL);
|
|
void LowerFAULTING_LOAD_OP(const MachineInstr &MI, X86MCInstLower &MCIL);
|
|
void LowerPATCHABLE_OP(const MachineInstr &MI, X86MCInstLower &MCIL);
|
|
|
|
void LowerTlsAddr(X86MCInstLower &MCInstLowering, const MachineInstr &MI);
|
|
|
|
public:
|
|
explicit X86AsmPrinter(TargetMachine &TM,
|
|
std::unique_ptr<MCStreamer> Streamer)
|
|
: AsmPrinter(TM, std::move(Streamer)), SM(*this), FM(*this) {}
|
|
|
|
const char *getPassName() const override {
|
|
return "X86 Assembly / Object Emitter";
|
|
}
|
|
|
|
const X86Subtarget &getSubtarget() const { return *Subtarget; }
|
|
|
|
void EmitStartOfAsmFile(Module &M) override;
|
|
|
|
void EmitEndOfAsmFile(Module &M) override;
|
|
|
|
void EmitInstruction(const MachineInstr *MI) override;
|
|
|
|
void EmitBasicBlockEnd(const MachineBasicBlock &MBB) override {
|
|
SMShadowTracker.emitShadowPadding(*OutStreamer, getSubtargetInfo());
|
|
}
|
|
|
|
bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
|
|
unsigned AsmVariant, const char *ExtraCode,
|
|
raw_ostream &OS) override;
|
|
bool PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
|
|
unsigned AsmVariant, const char *ExtraCode,
|
|
raw_ostream &OS) override;
|
|
|
|
/// \brief Return the symbol for the specified constant pool entry.
|
|
MCSymbol *GetCPISymbol(unsigned CPID) const override;
|
|
|
|
bool doInitialization(Module &M) override {
|
|
SMShadowTracker.reset(0);
|
|
SM.reset();
|
|
return AsmPrinter::doInitialization(M);
|
|
}
|
|
|
|
bool runOnMachineFunction(MachineFunction &F) override;
|
|
};
|
|
|
|
} // end namespace llvm
|
|
|
|
#endif
|