1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
|
//===-- 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/MCSubtargetInfo.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);
assert(TheTarget && "Unable to create target!");
// Get the assembler info needed to setup the MCContext.
const MCAsmInfo *MAI = TheTarget->createMCAsmInfo(Triple);
if (!MAI)
return 0;
const MCInstrInfo *MII = TheTarget->createMCInstrInfo();
if (!MII)
return 0;
const MCRegisterInfo *MRI = TheTarget->createMCRegInfo(Triple);
if (!MRI)
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;
DisAsm->setupForSymbolicDisassembly(GetOpInfo, SymbolLookUp, DisInfo, Ctx);
// 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);
}
|
