/**************************************************************************
*
* Copyright 2009-2011 VMware, Inc.
* All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sub license, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice (including the
* next paragraph) shall be included in all copies or substantial portions
* of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
* IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
* ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
**************************************************************************/
#include <stddef.h>
#include <fstream>
#include <sstream>
#include <iomanip>
#include <llvm-c/Core.h>
#include <llvm-c/Disassembler.h>
#include <llvm/Support/raw_ostream.h>
#include <llvm/Support/Format.h>
#include <llvm/Support/Host.h>
#include <llvm/IR/Module.h>
#include "util/u_math.h"
#include "util/u_debug.h"
#include "lp_bld_debug.h"
#ifdef __linux__
#include <sys/stat.h>
#include <fcntl.h>
#endif
/**
* Check alignment.
*
* It is important that this check is not implemented as a macro or inlined
* function, as the compiler assumptions in respect to alignment of global
* and stack variables would often make the check a no op, defeating the
* whole purpose of the exercise.
*/
extern "C" boolean
lp_check_alignment(const void *ptr, unsigned alignment)
{
assert(util_is_power_of_two(alignment));
return ((uintptr_t)ptr & (alignment - 1)) == 0;
}
/**
* Same as LLVMDumpValue, but through our debugging channels.
*/
extern "C" void
lp_debug_dump_value(LLVMValueRef value)
{
#if HAVE_LLVM >= 0x0304
char *str = LLVMPrintValueToString(value);
if (str) {
os_log_message(str);
LLVMDisposeMessage(str);
}
#elif defined(PIPE_OS_WINDOWS) || defined(PIPE_OS_EMBEDDED)
std::string str;
llvm::raw_string_ostream os(str);
llvm::unwrap(value)->print(os);
os_log_message(str.c_str());
#else
LLVMDumpValue(value);
#endif
}
/*
* 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, std::ostream &buffer)
{
const uint8_t *bytes = (const uint8_t *)func;
/*
* Limit disassembly to this extent
*/
const uint64_t extent = 96 * 1024;
/*
* Initialize all used objects.
*/
const char *triple = LLVM_HOST_TRIPLE;
LLVMDisasmContextRef D = LLVMCreateDisasm(triple, NULL, 0, NULL, NULL);
char outline[1024];
if (!D) {
buffer << "error: could not 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.
*/
buffer << std::setw(6) << (unsigned long)pc << ":\t";
Size = LLVMDisasmInstruction(D, (uint8_t *)bytes + pc, extent - pc, 0, outline,
sizeof outline);
if (!Size) {
buffer << "invalid\n";
pc += 1;
break;
}
/*
* Output the bytes in hexidecimal format.
*/
if (0) {
unsigned i;
for (i = 0; i < Size; ++i) {
buffer << std::hex << std::setfill('0') << std::setw(2)
<< static_cast<int> (bytes[pc + i]);
}
for (; i < 16; ++i) {
buffer << std::dec << " ";
}
}
/*
* Print the instruction.
*/
buffer << std::setw(Size) << outline << '\n';
/*
* Stop disassembling on return statements, if there is no record of a
* jump to a successive address.
*
* XXX: This currently assumes x86
*/
#if defined(PIPE_ARCH_X86) || defined(PIPE_ARCH_X86_64)
if (Size == 1 && bytes[pc] == 0xc3) {
break;
}
#endif
/*
* Advance.
*/
pc += Size;
if (pc >= extent) {
buffer << "disassembly larger than " << extent << " bytes, aborting\n";
break;
}
}
buffer << '\n';
LLVMDisasmDispose(D);
/*
* Print GDB command, useful to verify output.
*/
if (0) {
buffer << "disassemble " << static_cast<const void*>(bytes) << ' '
<< static_cast<const void*>(bytes + pc) << '\n';
}
return pc;
}
extern "C" void
lp_disassemble(LLVMValueRef func, const void *code)
{
std::ostringstream buffer;
std::string s;
buffer << LLVMGetValueName(func) << ":\n";
disassemble(code, buffer);
s = buffer.str();
os_log_message(s.c_str());
os_log_message("\n");
}
/*
* Linux perf profiler integration.
*
* See also:
* - http://penberg.blogspot.co.uk/2009/06/jato-has-profiler.html
* - https://github.com/penberg/jato/commit/73ad86847329d99d51b386f5aba692580d1f8fdc
* - http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=commitdiff;h=80d496be89ed7dede5abee5c057634e80a31c82d
*/
extern "C" void
lp_profile(LLVMValueRef func, const void *code)
{
#if defined(__linux__) && defined(PROFILE)
static std::ofstream perf_asm_file;
static boolean first_time = TRUE;
static FILE *perf_map_file = NULL;
if (first_time) {
/*
* We rely on the disassembler for determining a function's size, but
* the disassembly is a leaky and slow operation, so avoid running
* this except when running inside linux perf, which can be inferred
* by the PERF_BUILDID_DIR environment variable.
*/
if (getenv("PERF_BUILDID_DIR")) {
pid_t pid = getpid();
char filename[256];
util_snprintf(filename, sizeof filename, "/tmp/perf-%llu.map", (unsigned long long)pid);
perf_map_file = fopen(filename, "wt");
util_snprintf(filename, sizeof filename, "/tmp/perf-%llu.map.asm", (unsigned long long)pid);
perf_asm_file.open(filename);
}
first_time = FALSE;
}
if (perf_map_file) {
const char *symbol = LLVMGetValueName(func);
unsigned long addr = (uintptr_t)code;
perf_asm_file << symbol << ":\n";
unsigned long size = disassemble(code, perf_asm_file);
perf_asm_file.flush();
fprintf(perf_map_file, "%lx %lx %s\n", addr, size, symbol);
fflush(perf_map_file);
}
#else
(void)func;
(void)code;
#endif
}