src/gallium/auxiliary/gallivm/lp_bld_debug.cpp

   1 /**************************************************************************
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   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
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   9  * without limitation the rights to use, copy, modify, merge, publish,
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  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
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  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 <stddef.h>
  29
  30 #include <llvm-c/Core.h>
  31 #include <llvm/Target/TargetMachine.h>
  32 #include <llvm/Target/TargetInstrInfo.h>
  33 #include <llvm/Support/raw_ostream.h>
  34 #include <llvm/Support/Format.h>
  35 #include <llvm/Support/MemoryObject.h>
  36
  37 #if HAVE_LLVM >= 0x0300
  38 #include <llvm/Support/TargetRegistry.h>
  39 #else /* HAVE_LLVM < 0x0300 */
  40 #include <llvm/Target/TargetRegistry.h>
  41 #endif /* HAVE_LLVM < 0x0300 */
  42
  43 #if HAVE_LLVM >= 0x0209
  44 #include <llvm/Support/Host.h>
  45 #else /* HAVE_LLVM < 0x0209 */
  46 #include <llvm/System/Host.h>
  47 #endif /* HAVE_LLVM < 0x0209 */
  48
  49 #if HAVE_LLVM >= 0x0207
  50 #include <llvm/MC/MCDisassembler.h>
  51 #include <llvm/MC/MCAsmInfo.h>
  52 #include <llvm/MC/MCInst.h>
  53 #include <llvm/MC/MCInstPrinter.h>
  54 #endif /* HAVE_LLVM >= 0x0207 */
  55 #if HAVE_LLVM >= 0x0301
  56 #include <llvm/MC/MCRegisterInfo.h>
  57 #endif /* HAVE_LLVM >= 0x0301 */
  58
  59 #if HAVE_LLVM >= 0x0303
  60 #include <llvm/ADT/OwningPtr.h>
  61 #endif
  62
  63 #include "util/u_math.h"
  64 #include "util/u_debug.h"
  65
  66 #include "lp_bld_debug.h"
  67
  68 #ifdef __linux__
  69 #include <sys/stat.h>
  70 #include <fcntl.h>
  71 #endif
  72
  73
  74
  75 /**
  76  * Check alignment.
  77  *
  78  * It is important that this check is not implemented as a macro or inlined
  79  * function, as the compiler assumptions in respect to alignment of global
  80  * and stack variables would often make the check a no op, defeating the
  81  * whole purpose of the exercise.
  82  */
  83 extern "C" boolean
  84 lp_check_alignment(const void *ptr, unsigned alignment)
  85 {
  86    assert(util_is_power_of_two(alignment));
  87    return ((uintptr_t)ptr & (alignment - 1)) == 0;
  88 }
  89
  90
  91 class raw_debug_ostream :
  92    public llvm::raw_ostream
  93 {
  94 private:
  95    uint64_t pos;
  96
  97 public:
  98    raw_debug_ostream() : pos(0) { }
  99
 100    void write_impl(const char *Ptr, size_t Size);
 101
 102 #if HAVE_LLVM >= 0x207
 103    uint64_t current_pos() const { return pos; }
 104    size_t preferred_buffer_size() const { return 512; }
 105 #else
 106    uint64_t current_pos() { return pos; }
 107    size_t preferred_buffer_size() { return 512; }
 108 #endif
 109 };
 110
 111
 112 void
 113 raw_debug_ostream::write_impl(const char *Ptr, size_t Size)
 114 {
 115    if (Size > 0) {
 116       char *lastPtr = (char *)&Ptr[Size];
 117       char last = *lastPtr;
 118       *lastPtr = 0;
 119       _debug_printf("%*s", Size, Ptr);
 120       *lastPtr = last;
 121       pos += Size;
 122    }
 123 }
 124
 125
 126 /**
 127  * Same as LLVMDumpValue, but through our debugging channels.
 128  */
 129 extern "C" void
 130 lp_debug_dump_value(LLVMValueRef value)
 131 {
 132 #if (defined(PIPE_OS_WINDOWS) && !defined(PIPE_CC_MSVC)) || defined(PIPE_OS_EMBDDED)
 133    raw_debug_ostream os;
 134    llvm::unwrap(value)->print(os);
 135    os.flush();
 136 #else
 137    LLVMDumpValue(value);
 138 #endif
 139 }
 140
 141
 142 #if HAVE_LLVM >= 0x0207
 143 /*
 144  * MemoryObject wrapper around a buffer of memory, to be used by MC
 145  * disassembler.
 146  */
 147 class BufferMemoryObject:
 148    public llvm::MemoryObject
 149 {
 150 private:
 151    const uint8_t *Bytes;
 152    uint64_t Length;
 153 public:
 154    BufferMemoryObject(const uint8_t *bytes, uint64_t length) :
 155       Bytes(bytes), Length(length)
 156    {
 157    }
 158
 159    uint64_t getBase() const
 160    {
 161       return 0;
 162    }
 163
 164    uint64_t getExtent() const
 165    {
 166       return Length;
 167    }
 168
 169    int readByte(uint64_t addr, uint8_t *byte) const
 170    {
 171       if (addr > getExtent())
 172          return -1;
 173       *byte = Bytes[addr];
 174       return 0;
 175    }
 176 };
 177 #endif /* HAVE_LLVM >= 0x0207 */
 178
 179
 180 /*
 181  * Disassemble a function, using the LLVM MC disassembler.
 182  *
 183  * See also:
 184  * - http://blog.llvm.org/2010/01/x86-disassembler.html
 185  * - http://blog.llvm.org/2010/04/intro-to-llvm-mc-project.html
 186  */
 187 static size_t
 188 disassemble(const void* func, llvm::raw_ostream & Out)
 189 {
 190 #if HAVE_LLVM >= 0x0207
 191    using namespace llvm;
 192
 193    const uint8_t *bytes = (const uint8_t *)func;
 194
 195    /*
 196     * Limit disassembly to this extent
 197     */
 198    const uint64_t extent = 96 * 1024;
 199
 200    uint64_t max_pc = 0;
 201
 202    /*
 203     * Initialize all used objects.
 204     */
 205
 206 #if HAVE_LLVM >= 0x0301
 207    std::string Triple = sys::getDefaultTargetTriple();
 208 #else
 209    std::string Triple = sys::getHostTriple();
 210 #endif
 211
 212    std::string Error;
 213    const Target *T = TargetRegistry::lookupTarget(Triple, Error);
 214
 215 #if HAVE_LLVM >= 0x0304
 216    OwningPtr<const MCAsmInfo> AsmInfo(T->createMCAsmInfo(*T->createMCRegInfo(Triple), Triple));
 217 #elif HAVE_LLVM >= 0x0300
 218    OwningPtr<const MCAsmInfo> AsmInfo(T->createMCAsmInfo(Triple));
 219 #else
 220    OwningPtr<const MCAsmInfo> AsmInfo(T->createAsmInfo(Triple));
 221 #endif
 222
 223    if (!AsmInfo) {
 224       Out << "error: no assembly info for target " << Triple << "\n";
 225       return 0;
 226    }
 227
 228 #if HAVE_LLVM >= 0x0300
 229    const MCSubtargetInfo *STI = T->createMCSubtargetInfo(Triple, sys::getHostCPUName(), "");
 230    OwningPtr<const MCDisassembler> DisAsm(T->createMCDisassembler(*STI));
 231 #else
 232    OwningPtr<const MCDisassembler> DisAsm(T->createMCDisassembler());
 233 #endif
 234    if (!DisAsm) {
 235       Out << "error: no disassembler for target " << Triple << "\n";
 236       return 0;
 237    }
 238
 239 #if HAVE_LLVM >= 0x0300
 240    unsigned int AsmPrinterVariant = AsmInfo->getAssemblerDialect();
 241 #else
 242    int AsmPrinterVariant = AsmInfo->getAssemblerDialect();
 243 #endif
 244
 245 #if HAVE_LLVM >= 0x0301
 246    OwningPtr<const MCRegisterInfo> MRI(T->createMCRegInfo(Triple));
 247    if (!MRI) {
 248       Out << "error: no register info for target " << Triple.c_str() << "\n";
 249       return 0;
 250    }
 251
 252    OwningPtr<const MCInstrInfo> MII(T->createMCInstrInfo());
 253    if (!MII) {
 254       Out << "error: no instruction info for target " << Triple.c_str() << "\n";
 255       return 0;
 256    }
 257 #endif
 258
 259 #if HAVE_LLVM >= 0x0301
 260    OwningPtr<MCInstPrinter> Printer(
 261          T->createMCInstPrinter(AsmPrinterVariant, *AsmInfo, *MII, *MRI, *STI));
 262 #elif HAVE_LLVM == 0x0300
 263    OwningPtr<MCInstPrinter> Printer(
 264          T->createMCInstPrinter(AsmPrinterVariant, *AsmInfo, *STI));
 265 #elif HAVE_LLVM >= 0x0208
 266    OwningPtr<MCInstPrinter> Printer(
 267          T->createMCInstPrinter(AsmPrinterVariant, *AsmInfo));
 268 #else
 269    OwningPtr<MCInstPrinter> Printer(
 270          T->createMCInstPrinter(AsmPrinterVariant, *AsmInfo, Out));
 271 #endif
 272    if (!Printer) {
 273       Out << "error: no instruction printer for target " << Triple.c_str() << "\n";
 274       return 0;
 275    }
 276
 277 #if HAVE_LLVM >= 0x0301
 278    TargetOptions options;
 279 #if defined(DEBUG)
 280    options.JITEmitDebugInfo = true;
 281 #endif
 282 #if defined(PIPE_ARCH_X86)
 283    options.StackAlignmentOverride = 4;
 284 #endif
 285 #if defined(DEBUG) || defined(PROFILE)
 286    options.NoFramePointerElim = true;
 287 #endif
 288    TargetMachine *TM = T->createTargetMachine(Triple, sys::getHostCPUName(), "", options);
 289 #elif HAVE_LLVM == 0x0300
 290    TargetMachine *TM = T->createTargetMachine(Triple, sys::getHostCPUName(), "");
 291 #else
 292    TargetMachine *TM = T->createTargetMachine(Triple, "");
 293 #endif
 294
 295    const TargetInstrInfo *TII = TM->getInstrInfo();
 296
 297    /*
 298     * Wrap the data in a MemoryObject
 299     */
 300    BufferMemoryObject memoryObject((const uint8_t *)bytes, extent);
 301
 302    uint64_t pc;
 303    pc = 0;
 304    while (true) {
 305       MCInst Inst;
 306       uint64_t Size;
 307
 308       /*
 309        * Print address.  We use addresses relative to the start of the function,
 310        * so that between runs.
 311        */
 312
 313       Out << llvm::format("%6lu:\t", (unsigned long)pc);
 314
 315       if (!DisAsm->getInstruction(Inst, Size, memoryObject,
 316                                  pc,
 317 #if HAVE_LLVM >= 0x0300
 318                                   nulls(), nulls())) {
 319 #else
 320                                   nulls())) {
 321 #endif
 322          Out << "invalid";
 323          pc += 1;
 324       }
 325
 326       /*
 327        * Output the bytes in hexidecimal format.
 328        */
 329
 330       if (0) {
 331          unsigned i;
 332          for (i = 0; i < Size; ++i) {
 333             Out << llvm::format("%02x ", ((const uint8_t*)bytes)[pc + i]);
 334          }
 335          for (; i < 16; ++i) {
 336             Out << "   ";
 337          }
 338       }
 339
 340       /*
 341        * Print the instruction.
 342        */
 343 #if HAVE_LLVM >= 0x0300
 344          Printer->printInst(&Inst, Out, "");
 345 #elif HAVE_LLVM >= 0x208
 346          Printer->printInst(&Inst, Out);
 347 #else
 348          Printer->printInst(&Inst);
 349 #endif
 350
 351       /*
 352        * Advance.
 353        */
 354
 355       pc += Size;
 356
 357 #if HAVE_LLVM >= 0x0300
 358       const MCInstrDesc &TID = TII->get(Inst.getOpcode());
 359 #else
 360       const TargetInstrDesc &TID = TII->get(Inst.getOpcode());
 361 #endif
 362
 363       /*
 364        * Keep track of forward jumps to a nearby address.
 365        */
 366
 367       if (TID.isBranch()) {
 368          for (unsigned i = 0; i < Inst.getNumOperands(); ++i) {
 369             const MCOperand &operand = Inst.getOperand(i);
 370             if (operand.isImm()) {
 371                uint64_t jump;
 372
 373                /*
 374                 * FIXME: Handle both relative and absolute addresses correctly.
 375                 * EDInstInfo actually has this info, but operandTypes and
 376                 * operandFlags enums are not exposed in the public interface.
 377                 */
 378
 379                if (1) {
 380                   /*
 381                    * PC relative addr.
 382                    */
 383
 384                   jump = pc + operand.getImm();
 385                } else {
 386                   /*
 387                    * Absolute addr.
 388                    */
 389
 390                   jump = (uint64_t)operand.getImm();
 391                }
 392
 393                /*
 394                 * Output the address relative to the function start, given
 395                 * that MC will print the addresses relative the current pc.
 396                 */
 397                Out << "\t\t; " << jump;
 398
 399                /*
 400                 * Ignore far jumps given it could be actually a tail return to
 401                 * a random address.
 402                 */
 403
 404                if (jump > max_pc &&
 405                    jump < extent) {
 406                   max_pc = jump;
 407                }
 408             }
 409          }
 410       }
 411
 412       Out << "\n";
 413
 414       /*
 415        * Stop disassembling on return statements, if there is no record of a
 416        * jump to a successive address.
 417        */
 418
 419       if (TID.isReturn()) {
 420          if (pc > max_pc) {
 421             break;
 422          }
 423       }
 424    }
 425
 426    /*
 427     * Print GDB command, useful to verify output.
 428     */
 429
 430    if (0) {
 431       _debug_printf("disassemble %p %p\n", bytes, bytes + pc);
 432    }
 433
 434    Out << "\n";
 435    Out.flush();
 436
 437    return pc;
 438 #else /* HAVE_LLVM < 0x0207 */
 439    (void)func;
 440    return 0;
 441 #endif /* HAVE_LLVM < 0x0207 */
 442 }
 443
 444
 445 extern "C" void
 446 lp_disassemble(LLVMValueRef func, const void *code) {
 447    raw_debug_ostream Out;
 448    disassemble(code, Out);
 449 }
 450
 451
 452 /*
 453  * Linux perf profiler integration.
 454  *
 455  * See also:
 456  * - http://penberg.blogspot.co.uk/2009/06/jato-has-profiler.html
 457  * - https://github.com/penberg/jato/commit/73ad86847329d99d51b386f5aba692580d1f8fdc
 458  * - http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=commitdiff;h=80d496be89ed7dede5abee5c057634e80a31c82d
 459  */
 460 extern "C" void
 461 lp_profile(LLVMValueRef func, const void *code)
 462 {
 463 #if defined(__linux__) && (defined(DEBUG) || defined(PROFILE))
 464    static boolean first_time = TRUE;
 465    static FILE *perf_map_file = NULL;
 466    static int perf_asm_fd = -1;
 467    if (first_time) {
 468       /*
 469        * We rely on the disassembler for determining a function's size, but
 470        * the disassembly is a leaky and slow operation, so avoid running
 471        * this except when running inside linux perf, which can be inferred
 472        * by the PERF_BUILDID_DIR environment variable.
 473        */
 474       if (getenv("PERF_BUILDID_DIR")) {
 475          pid_t pid = getpid();
 476          char filename[256];
 477          util_snprintf(filename, sizeof filename, "/tmp/perf-%llu.map", (unsigned long long)pid);
 478          perf_map_file = fopen(filename, "wt");
 479          util_snprintf(filename, sizeof filename, "/tmp/perf-%llu.map.asm", (unsigned long long)pid);
 480          mode_t mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH;
 481          perf_asm_fd = open(filename, O_WRONLY | O_CREAT, mode);
 482       }
 483       first_time = FALSE;
 484    }
 485    if (perf_map_file) {
 486       const char *symbol = LLVMGetValueName(func);
 487       unsigned long addr = (uintptr_t)code;
 488       llvm::raw_fd_ostream Out(perf_asm_fd, false);
 489       Out << symbol << ":\n";
 490       unsigned long size = disassemble(code, Out);
 491       fprintf(perf_map_file, "%lx %lx %s\n", addr, size, symbol);
 492       fflush(perf_map_file);
 493    }
 494 #else
 495    (void)func;
 496    (void)code;
 497 #endif
 498 }
 499
 500