static void do_disassemble(const char *triple, const char *features,
unsigned char *buf, int siz) {
LLVMDisasmContextRef D = LLVMCreateDisasmCPUFeatures(triple, "", features,
NULL, 0, NULL, NULL);
char outline[1024];
int pos;
if (!D) {
printf("ERROR: Couldn't create disassembler for triple %s\n", triple);
return;
}
pos = 0;
while (pos < siz) {
size_t l = LLVMDisasmInstruction(D, buf + pos, siz - pos, 0, outline,
sizeof(outline));
if (!l) {
pprint(pos, buf + pos, 1, "\t???");
pos++;
} else {
pprint(pos, buf + pos, l, outline);
pos += l;
}
}
LLVMDisasmDispose(D);
}
/*
* Disassemble a function, using the LLVM MC disassembler.
*
* See also:
* - http://blog.llvm.org/2010/01/x86-disassembler.html
* - http://blog.llvm.org/2010/04/intro-to-llvm-mc-project.html
*/
static size_t
disassemble(const void* func, llvm::raw_ostream & Out)
{
const uint8_t *bytes = (const uint8_t *)func;
/*
* Limit disassembly to this extent
*/
const uint64_t extent = 96 * 1024;
/*
* Initialize all used objects.
*/
std::string Triple = llvm::sys::getProcessTriple();
LLVMDisasmContextRef D = LLVMCreateDisasm(Triple.c_str(), NULL, 0, NULL, NULL);
char outline[1024];
if (!D) {
Out << "error: couldn't create disassembler for triple " << Triple << "\n";
return 0;
}
uint64_t pc;
pc = 0;
while (pc < extent) {
size_t Size;
/*
* Print address. We use addresses relative to the start of the function,
* so that between runs.
*/
Out << llvm::format("%6lu:\t", (unsigned long)pc);
Size = LLVMDisasmInstruction(D, (uint8_t *)bytes + pc, extent - pc, 0, outline,
sizeof outline);
if (!Size) {
Out << "invalid\n";
pc += 1;
break;
}
/*
* Output the bytes in hexidecimal format.
*/
if (0) {
unsigned i;
for (i = 0; i < Size; ++i) {
Out << llvm::format("%02x ", bytes[pc + i]);
}
for (; i < 16; ++i) {
Out << " ";
}
}
/*
* Print the instruction.
*/
Out << outline;
Out << "\n";
/*
* Stop disassembling on return statements, if there is no record of a
* jump to a successive address.
*
* XXX: This currently assumes x86
*/
if (Size == 1 && bytes[pc] == 0xc3) {
break;
}
/*
* Advance.
*/
pc += Size;
if (pc >= extent) {
Out << "disassembly larger than " << extent << "bytes, aborting\n";
break;
}
}
Out << "\n";
Out.flush();
LLVMDisasmDispose(D);
/*
* Print GDB command, useful to verify output.
*/
if (0) {
_debug_printf("disassemble %p %p\n", bytes, bytes + pc);
}
return pc;
}
~HostDisassemblerLLVM()
{
if (m_can_disasm)
LLVMDisasmDispose(m_llvm_context);
}
