llvm-6502/lib/MC/MCDisassembler/Disassembler.cpp
Bill Wendling 99cb622041 Use pointers to the MCAsmInfo and MCRegInfo.
Someone may want to do something crazy, like replace these objects if they
change or something.

No functionality change intended.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@184175 91177308-0d34-0410-b5e6-96231b3b80d8
2013-06-18 07:20:20 +00:00

237 lines
8.4 KiB
C++

//===-- lib/MC/Disassembler.cpp - Disassembler Public C Interface ---------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "Disassembler.h"
#include "llvm-c/Disassembler.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCDisassembler.h"
#include "llvm/MC/MCInst.h"
#include "llvm/MC/MCInstPrinter.h"
#include "llvm/MC/MCInstrInfo.h"
#include "llvm/MC/MCRegisterInfo.h"
#include "llvm/MC/MCRelocationInfo.h"
#include "llvm/MC/MCSubtargetInfo.h"
#include "llvm/MC/MCSymbolizer.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/MemoryObject.h"
#include "llvm/Support/TargetRegistry.h"
namespace llvm {
class Target;
} // namespace llvm
using namespace llvm;
// LLVMCreateDisasm() creates a disassembler for the TripleName. Symbolic
// disassembly is supported by passing a block of information in the DisInfo
// parameter and specifying the TagType and callback functions as described in
// the header llvm-c/Disassembler.h . The pointer to the block and the
// functions can all be passed as NULL. If successful, this returns a
// disassembler context. If not, it returns NULL.
//
LLVMDisasmContextRef LLVMCreateDisasmCPU(const char *Triple, const char *CPU,
void *DisInfo, int TagType,
LLVMOpInfoCallback GetOpInfo,
LLVMSymbolLookupCallback SymbolLookUp){
// Get the target.
std::string Error;
const Target *TheTarget = TargetRegistry::lookupTarget(Triple, Error);
if (!TheTarget)
return 0;
const MCRegisterInfo *MRI = TheTarget->createMCRegInfo(Triple);
if (!MRI)
return 0;
// Get the assembler info needed to setup the MCContext.
const MCAsmInfo *MAI = TheTarget->createMCAsmInfo(*MRI, Triple);
if (!MAI)
return 0;
const MCInstrInfo *MII = TheTarget->createMCInstrInfo();
if (!MII)
return 0;
// Package up features to be passed to target/subtarget
std::string FeaturesStr;
const MCSubtargetInfo *STI = TheTarget->createMCSubtargetInfo(Triple, CPU,
FeaturesStr);
if (!STI)
return 0;
// Set up the MCContext for creating symbols and MCExpr's.
MCContext *Ctx = new MCContext(MAI, MRI, 0);
if (!Ctx)
return 0;
// Set up disassembler.
MCDisassembler *DisAsm = TheTarget->createMCDisassembler(*STI);
if (!DisAsm)
return 0;
OwningPtr<MCRelocationInfo> RelInfo(
TheTarget->createMCRelocationInfo(Triple, *Ctx));
if (!RelInfo)
return 0;
OwningPtr<MCSymbolizer> Symbolizer(
TheTarget->createMCSymbolizer(Triple, GetOpInfo, SymbolLookUp, DisInfo,
Ctx, RelInfo.take()));
DisAsm->setSymbolizer(Symbolizer);
DisAsm->setupForSymbolicDisassembly(GetOpInfo, SymbolLookUp, DisInfo,
Ctx, RelInfo);
// Set up the instruction printer.
int AsmPrinterVariant = MAI->getAssemblerDialect();
MCInstPrinter *IP = TheTarget->createMCInstPrinter(AsmPrinterVariant,
*MAI, *MII, *MRI, *STI);
if (!IP)
return 0;
LLVMDisasmContext *DC = new LLVMDisasmContext(Triple, DisInfo, TagType,
GetOpInfo, SymbolLookUp,
TheTarget, MAI, MRI,
STI, MII, Ctx, DisAsm, IP);
if (!DC)
return 0;
return DC;
}
LLVMDisasmContextRef LLVMCreateDisasm(const char *Triple, void *DisInfo,
int TagType, LLVMOpInfoCallback GetOpInfo,
LLVMSymbolLookupCallback SymbolLookUp) {
return LLVMCreateDisasmCPU(Triple, "", DisInfo, TagType, GetOpInfo,
SymbolLookUp);
}
//
// LLVMDisasmDispose() disposes of the disassembler specified by the context.
//
void LLVMDisasmDispose(LLVMDisasmContextRef DCR){
LLVMDisasmContext *DC = (LLVMDisasmContext *)DCR;
delete DC;
}
namespace {
//
// The memory object created by LLVMDisasmInstruction().
//
class DisasmMemoryObject : public MemoryObject {
uint8_t *Bytes;
uint64_t Size;
uint64_t BasePC;
public:
DisasmMemoryObject(uint8_t *bytes, uint64_t size, uint64_t basePC) :
Bytes(bytes), Size(size), BasePC(basePC) {}
uint64_t getBase() const { return BasePC; }
uint64_t getExtent() const { return Size; }
int readByte(uint64_t Addr, uint8_t *Byte) const {
if (Addr - BasePC >= Size)
return -1;
*Byte = Bytes[Addr - BasePC];
return 0;
}
};
} // end anonymous namespace
//
// LLVMDisasmInstruction() disassembles a single instruction using the
// disassembler context specified in the parameter DC. The bytes of the
// instruction are specified in the parameter Bytes, and contains at least
// BytesSize number of bytes. The instruction is at the address specified by
// the PC parameter. If a valid instruction can be disassembled its string is
// returned indirectly in OutString which whos size is specified in the
// parameter OutStringSize. This function returns the number of bytes in the
// instruction or zero if there was no valid instruction. If this function
// returns zero the caller will have to pick how many bytes they want to step
// over by printing a .byte, .long etc. to continue.
//
size_t LLVMDisasmInstruction(LLVMDisasmContextRef DCR, uint8_t *Bytes,
uint64_t BytesSize, uint64_t PC, char *OutString,
size_t OutStringSize){
LLVMDisasmContext *DC = (LLVMDisasmContext *)DCR;
// Wrap the pointer to the Bytes, BytesSize and PC in a MemoryObject.
DisasmMemoryObject MemoryObject(Bytes, BytesSize, PC);
uint64_t Size;
MCInst Inst;
const MCDisassembler *DisAsm = DC->getDisAsm();
MCInstPrinter *IP = DC->getIP();
MCDisassembler::DecodeStatus S;
S = DisAsm->getInstruction(Inst, Size, MemoryObject, PC,
/*REMOVE*/ nulls(), DC->CommentStream);
switch (S) {
case MCDisassembler::Fail:
case MCDisassembler::SoftFail:
// FIXME: Do something different for soft failure modes?
return 0;
case MCDisassembler::Success: {
DC->CommentStream.flush();
StringRef Comments = DC->CommentsToEmit.str();
SmallVector<char, 64> InsnStr;
raw_svector_ostream OS(InsnStr);
IP->printInst(&Inst, OS, Comments);
OS.flush();
// Tell the comment stream that the vector changed underneath it.
DC->CommentsToEmit.clear();
DC->CommentStream.resync();
assert(OutStringSize != 0 && "Output buffer cannot be zero size");
size_t OutputSize = std::min(OutStringSize-1, InsnStr.size());
std::memcpy(OutString, InsnStr.data(), OutputSize);
OutString[OutputSize] = '\0'; // Terminate string.
return Size;
}
}
llvm_unreachable("Invalid DecodeStatus!");
}
//
// LLVMSetDisasmOptions() sets the disassembler's options. It returns 1 if it
// can set all the Options and 0 otherwise.
//
int LLVMSetDisasmOptions(LLVMDisasmContextRef DCR, uint64_t Options){
if (Options & LLVMDisassembler_Option_UseMarkup){
LLVMDisasmContext *DC = (LLVMDisasmContext *)DCR;
MCInstPrinter *IP = DC->getIP();
IP->setUseMarkup(1);
Options &= ~LLVMDisassembler_Option_UseMarkup;
}
if (Options & LLVMDisassembler_Option_PrintImmHex){
LLVMDisasmContext *DC = (LLVMDisasmContext *)DCR;
MCInstPrinter *IP = DC->getIP();
IP->setPrintImmHex(1);
Options &= ~LLVMDisassembler_Option_PrintImmHex;
}
if (Options & LLVMDisassembler_Option_AsmPrinterVariant){
LLVMDisasmContext *DC = (LLVMDisasmContext *)DCR;
// Try to set up the new instruction printer.
const MCAsmInfo *MAI = DC->getAsmInfo();
const MCInstrInfo *MII = DC->getInstrInfo();
const MCRegisterInfo *MRI = DC->getRegisterInfo();
const MCSubtargetInfo *STI = DC->getSubtargetInfo();
int AsmPrinterVariant = MAI->getAssemblerDialect();
AsmPrinterVariant = AsmPrinterVariant == 0 ? 1 : 0;
MCInstPrinter *IP = DC->getTarget()->createMCInstPrinter(
AsmPrinterVariant, *MAI, *MII, *MRI, *STI);
if (IP) {
DC->setIP(IP);
Options &= ~LLVMDisassembler_Option_AsmPrinterVariant;
}
}
return (Options == 0);
}