lp_bld_debug.cpp revision 1795372feec77e62cbe150f5853e063b9e53acd2
1/************************************************************************** 2 * 3 * Copyright 2009-2011 VMware, Inc. 4 * All Rights Reserved. 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a 7 * copy of this software and associated documentation files (the 8 * "Software"), to deal in the Software without restriction, including 9 * without limitation the rights to use, copy, modify, merge, publish, 10 * distribute, sub license, and/or sell copies of the Software, and to 11 * permit persons to whom the Software is furnished to do so, subject to 12 * the following conditions: 13 * 14 * The above copyright notice and this permission notice (including the 15 * next paragraph) shall be included in all copies or substantial portions 16 * of the Software. 17 * 18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. 21 * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR 22 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, 23 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE 24 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 25 * 26 **************************************************************************/ 27 28#include <llvm-c/Core.h> 29#include <llvm/Target/TargetMachine.h> 30#include <llvm/Target/TargetInstrInfo.h> 31#include <llvm/Support/raw_ostream.h> 32#include <llvm/Support/MemoryObject.h> 33 34#if HAVE_LLVM >= 0x0300 35#include <llvm/Support/TargetRegistry.h> 36#include <llvm/Support/TargetSelect.h> 37#else /* HAVE_LLVM < 0x0300 */ 38#include <llvm/Target/TargetRegistry.h> 39#include <llvm/Target/TargetSelect.h> 40#endif /* HAVE_LLVM < 0x0300 */ 41 42#if HAVE_LLVM >= 0x0209 43#include <llvm/Support/Host.h> 44#else /* HAVE_LLVM < 0x0209 */ 45#include <llvm/System/Host.h> 46#endif /* HAVE_LLVM < 0x0209 */ 47 48#if HAVE_LLVM >= 0x0207 49#include <llvm/MC/MCDisassembler.h> 50#include <llvm/MC/MCAsmInfo.h> 51#include <llvm/MC/MCInst.h> 52#include <llvm/MC/MCInstPrinter.h> 53#endif /* HAVE_LLVM >= 0x0207 */ 54 55#include "util/u_math.h" 56#include "util/u_debug.h" 57 58#include "lp_bld_debug.h" 59 60 61 62/** 63 * Check alignment. 64 * 65 * It is important that this check is not implemented as a macro or inlined 66 * function, as the compiler assumptions in respect to alignment of global 67 * and stack variables would often make the check a no op, defeating the 68 * whole purpose of the exercise. 69 */ 70extern "C" boolean 71lp_check_alignment(const void *ptr, unsigned alignment) 72{ 73 assert(util_is_power_of_two(alignment)); 74 return ((uintptr_t)ptr & (alignment - 1)) == 0; 75} 76 77 78class raw_debug_ostream : 79 public llvm::raw_ostream 80{ 81 uint64_t pos; 82 83 void write_impl(const char *Ptr, size_t Size); 84 uint64_t current_pos() { return pos; } 85 uint64_t current_pos() const { return pos; } 86 87#if HAVE_LLVM >= 0x207 88 uint64_t preferred_buffer_size() { return 512; } 89#else 90 size_t preferred_buffer_size() { return 512; } 91#endif 92}; 93 94 95void 96raw_debug_ostream::write_impl(const char *Ptr, size_t Size) 97{ 98 if (Size > 0) { 99 char *lastPtr = (char *)&Ptr[Size]; 100 char last = *lastPtr; 101 *lastPtr = 0; 102 _debug_printf("%*s", Size, Ptr); 103 *lastPtr = last; 104 pos += Size; 105 } 106} 107 108 109/** 110 * Same as LLVMDumpValue, but through our debugging channels. 111 */ 112extern "C" void 113lp_debug_dump_value(LLVMValueRef value) 114{ 115#if (defined(PIPE_OS_WINDOWS) && !defined(PIPE_CC_MSVC)) || defined(PIPE_OS_EMBDDED) 116 raw_debug_ostream os; 117 llvm::unwrap(value)->print(os); 118 os.flush(); 119#else 120 LLVMDumpValue(value); 121#endif 122} 123 124 125#if HAVE_LLVM >= 0x0207 126/* 127 * MemoryObject wrapper around a buffer of memory, to be used by MC 128 * disassembler. 129 */ 130class BufferMemoryObject: 131 public llvm::MemoryObject 132{ 133private: 134 const uint8_t *Bytes; 135 uint64_t Length; 136public: 137 BufferMemoryObject(const uint8_t *bytes, uint64_t length) : 138 Bytes(bytes), Length(length) 139 { 140 } 141 142 uint64_t getBase() const 143 { 144 return 0; 145 } 146 147 uint64_t getExtent() const 148 { 149 return Length; 150 } 151 152 int readByte(uint64_t addr, uint8_t *byte) const 153 { 154 if (addr > getExtent()) 155 return -1; 156 *byte = Bytes[addr]; 157 return 0; 158 } 159}; 160#endif /* HAVE_LLVM >= 0x0207 */ 161 162 163/* 164 * Disassemble a function, using the LLVM MC disassembler. 165 * 166 * See also: 167 * - http://blog.llvm.org/2010/01/x86-disassembler.html 168 * - http://blog.llvm.org/2010/04/intro-to-llvm-mc-project.html 169 */ 170extern "C" void 171lp_disassemble(const void* func) 172{ 173#if HAVE_LLVM >= 0x0207 174 using namespace llvm; 175 176 const uint8_t *bytes = (const uint8_t *)func; 177 178 /* 179 * Limit disassembly to this extent 180 */ 181 const uint64_t extent = 0x10000; 182 183 uint64_t max_pc = 0; 184 185 /* 186 * Initialize all used objects. 187 */ 188 189 std::string Triple = sys::getHostTriple(); 190 191 std::string Error; 192 const Target *T = TargetRegistry::lookupTarget(Triple, Error); 193 194#if HAVE_LLVM >= 0x0208 195 InitializeNativeTargetAsmPrinter(); 196#else 197 InitializeAllAsmPrinters(); 198#endif 199 200 InitializeAllDisassemblers(); 201 202#if HAVE_LLVM >= 0x0300 203 OwningPtr<const MCAsmInfo> AsmInfo(T->createMCAsmInfo(Triple)); 204#else 205 OwningPtr<const MCAsmInfo> AsmInfo(T->createAsmInfo(Triple)); 206#endif 207 208 if (!AsmInfo) { 209 debug_printf("error: no assembly info for target %s\n", Triple.c_str()); 210 return; 211 } 212 213#if HAVE_LLVM >= 0x0300 214 const MCSubtargetInfo *STI = T->createMCSubtargetInfo(Triple, sys::getHostCPUName(), ""); 215 OwningPtr<const MCDisassembler> DisAsm(T->createMCDisassembler(*STI)); 216#else 217 OwningPtr<const MCDisassembler> DisAsm(T->createMCDisassembler()); 218#endif 219 if (!DisAsm) { 220 debug_printf("error: no disassembler for target %s\n", Triple.c_str()); 221 return; 222 } 223 224 raw_debug_ostream Out; 225 226#if HAVE_LLVM >= 0x0300 227 unsigned int AsmPrinterVariant = AsmInfo->getAssemblerDialect(); 228#else 229 int AsmPrinterVariant = AsmInfo->getAssemblerDialect(); 230#endif 231 232#if HAVE_LLVM >= 0x0300 233 OwningPtr<MCInstPrinter> Printer( 234 T->createMCInstPrinter(AsmPrinterVariant, *AsmInfo, *STI)); 235#elif HAVE_LLVM >= 0x0208 236 OwningPtr<MCInstPrinter> Printer( 237 T->createMCInstPrinter(AsmPrinterVariant, *AsmInfo)); 238#else 239 OwningPtr<MCInstPrinter> Printer( 240 T->createMCInstPrinter(AsmPrinterVariant, *AsmInfo, Out)); 241#endif 242 if (!Printer) { 243 debug_printf("error: no instruction printer for target %s\n", Triple.c_str()); 244 return; 245 } 246 247#if HAVE_LLVM >= 0x0300 248 TargetMachine *TM = T->createTargetMachine(Triple, sys::getHostCPUName(), ""); 249#else 250 TargetMachine *TM = T->createTargetMachine(Triple, ""); 251#endif 252 253 const TargetInstrInfo *TII = TM->getInstrInfo(); 254 255 /* 256 * Wrap the data in a MemoryObject 257 */ 258 BufferMemoryObject memoryObject((const uint8_t *)bytes, extent); 259 260 uint64_t pc; 261 pc = 0; 262 while (true) { 263 MCInst Inst; 264 uint64_t Size; 265 266 /* 267 * Print address. We use addresses relative to the start of the function, 268 * so that between runs. 269 */ 270 271 debug_printf("%6lu:\t", (unsigned long)pc); 272 273 if (!DisAsm->getInstruction(Inst, Size, memoryObject, 274 pc, 275 nulls())) { 276 debug_printf("invalid\n"); 277 pc += 1; 278 } 279 280 /* 281 * Output the bytes in hexidecimal format. 282 */ 283 284 if (0) { 285 unsigned i; 286 for (i = 0; i < Size; ++i) { 287 debug_printf("%02x ", ((const uint8_t*)bytes)[pc + i]); 288 } 289 for (; i < 16; ++i) { 290 debug_printf(" "); 291 } 292 } 293 294 /* 295 * Print the instruction. 296 */ 297 298#if HAVE_LLVM >= 0x208 299 Printer->printInst(&Inst, Out); 300#else 301 Printer->printInst(&Inst); 302#endif 303 Out.flush(); 304 305 /* 306 * Advance. 307 */ 308 309 pc += Size; 310 311#if HAVE_LLVM >= 0x0300 312 const MCInstrDesc &TID = TII->get(Inst.getOpcode()); 313#else 314 const TargetInstrDesc &TID = TII->get(Inst.getOpcode()); 315#endif 316 317 /* 318 * Keep track of forward jumps to a nearby address. 319 */ 320 321 if (TID.isBranch()) { 322 for (unsigned i = 0; i < Inst.getNumOperands(); ++i) { 323 const MCOperand &operand = Inst.getOperand(i); 324 if (operand.isImm()) { 325 uint64_t jump; 326 327 /* 328 * FIXME: Handle both relative and absolute addresses correctly. 329 * EDInstInfo actually has this info, but operandTypes and 330 * operandFlags enums are not exposed in the public interface. 331 */ 332 333 if (1) { 334 /* 335 * PC relative addr. 336 */ 337 338 jump = pc + operand.getImm(); 339 } else { 340 /* 341 * Absolute addr. 342 */ 343 344 jump = (uint64_t)operand.getImm(); 345 } 346 347 /* 348 * Output the address relative to the function start, given 349 * that MC will print the addresses relative the current pc. 350 */ 351 debug_printf("\t\t; %lu", (unsigned long)jump); 352 353 /* 354 * Ignore far jumps given it could be actually a tail return to 355 * a random address. 356 */ 357 358 if (jump > max_pc && 359 jump < extent) { 360 max_pc = jump; 361 } 362 } 363 } 364 } 365 366 debug_printf("\n"); 367 368 /* 369 * Stop disassembling on return statements, if there is no record of a 370 * jump to a successive address. 371 */ 372 373 if (TID.isReturn()) { 374 if (pc > max_pc) { 375 break; 376 } 377 } 378 } 379 380 /* 381 * Print GDB command, useful to verify output. 382 */ 383 384 if (0) { 385 debug_printf("disassemble %p %p\n", bytes, bytes + pc); 386 } 387 388 debug_printf("\n"); 389#else /* HAVE_LLVM < 0x0207 */ 390 (void)func; 391#endif /* HAVE_LLVM < 0x0207 */ 392} 393 394