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