lp_bld_debug.cpp revision 834f515988ca894b3828a4929d36cafd349eade8 
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 <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/MemoryObject.h>
35
36#if HAVE_LLVM >= 0x0300
37#include <llvm/Support/TargetRegistry.h>
38#include <llvm/Support/TargetSelect.h>
39#else /* HAVE_LLVM < 0x0300 */
40#include <llvm/Target/TargetRegistry.h>
41#include <llvm/Target/TargetSelect.h>
42#endif /* HAVE_LLVM < 0x0300 */
43
44#if HAVE_LLVM >= 0x0209
45#include <llvm/Support/Host.h>
46#else /* HAVE_LLVM < 0x0209 */
47#include <llvm/System/Host.h>
48#endif /* HAVE_LLVM < 0x0209 */
49
50#if HAVE_LLVM >= 0x0207
51#include <llvm/MC/MCDisassembler.h>
52#include <llvm/MC/MCAsmInfo.h>
53#include <llvm/MC/MCInst.h>
54#include <llvm/MC/MCInstPrinter.h>
55#endif /* HAVE_LLVM >= 0x0207 */
56
57#include "util/u_math.h"
58#include "util/u_debug.h"
59
60#include "lp_bld_debug.h"
61
62
63
64/**
65 * Check alignment.
66 *
67 * It is important that this check is not implemented as a macro or inlined
68 * function, as the compiler assumptions in respect to alignment of global
69 * and stack variables would often make the check a no op, defeating the
70 * whole purpose of the exercise.
71 */
72extern "C" boolean
73lp_check_alignment(const void *ptr, unsigned alignment)
74{
75   assert(util_is_power_of_two(alignment));
76   return ((uintptr_t)ptr & (alignment - 1)) == 0;
77}
78
79
80class raw_debug_ostream :
81   public llvm::raw_ostream
82{
83   uint64_t pos;
84
85   void write_impl(const char *Ptr, size_t Size);
86   uint64_t current_pos() { return pos; }
87   uint64_t current_pos() const { return pos; }
88
89#if HAVE_LLVM >= 0x207
90   uint64_t preferred_buffer_size() { return 512; }
91#else
92   size_t preferred_buffer_size() { return 512; }
93#endif
94};
95
96
97void
98raw_debug_ostream::write_impl(const char *Ptr, size_t Size)
99{
100   if (Size > 0) {
101      char *lastPtr = (char *)&Ptr[Size];
102      char last = *lastPtr;
103      *lastPtr = 0;
104      _debug_printf("%*s", Size, Ptr);
105      *lastPtr = last;
106      pos += Size;
107   }
108}
109
110
111/**
112 * Same as LLVMDumpValue, but through our debugging channels.
113 */
114extern "C" void
115lp_debug_dump_value(LLVMValueRef value)
116{
117#if (defined(PIPE_OS_WINDOWS) && !defined(PIPE_CC_MSVC)) || defined(PIPE_OS_EMBDDED)
118   raw_debug_ostream os;
119   llvm::unwrap(value)->print(os);
120   os.flush();
121#else
122   LLVMDumpValue(value);
123#endif
124}
125
126
127#if HAVE_LLVM >= 0x0207
128/*
129 * MemoryObject wrapper around a buffer of memory, to be used by MC
130 * disassembler.
131 */
132class BufferMemoryObject:
133   public llvm::MemoryObject
134{
135private:
136   const uint8_t *Bytes;
137   uint64_t Length;
138public:
139   BufferMemoryObject(const uint8_t *bytes, uint64_t length) :
140      Bytes(bytes), Length(length)
141   {
142   }
143
144   uint64_t getBase() const
145   {
146      return 0;
147   }
148
149   uint64_t getExtent() const
150   {
151      return Length;
152   }
153
154   int readByte(uint64_t addr, uint8_t *byte) const
155   {
156      if (addr > getExtent())
157         return -1;
158      *byte = Bytes[addr];
159      return 0;
160   }
161};
162#endif /* HAVE_LLVM >= 0x0207 */
163
164
165/*
166 * Disassemble a function, using the LLVM MC disassembler.
167 *
168 * See also:
169 * - http://blog.llvm.org/2010/01/x86-disassembler.html
170 * - http://blog.llvm.org/2010/04/intro-to-llvm-mc-project.html
171 */
172extern "C" void
173lp_disassemble(const void* func)
174{
175#if HAVE_LLVM >= 0x0207
176   using namespace llvm;
177
178   const uint8_t *bytes = (const uint8_t *)func;
179
180   /*
181    * Limit disassembly to this extent
182    */
183   const uint64_t extent = 0x10000;
184
185   uint64_t max_pc = 0;
186
187   /*
188    * Initialize all used objects.
189    */
190
191#if HAVE_LLVM >= 0x0301
192   std::string Triple = sys::getDefaultTargetTriple();
193#else
194   std::string Triple = sys::getHostTriple();
195#endif
196
197   std::string Error;
198   const Target *T = TargetRegistry::lookupTarget(Triple, Error);
199
200#if HAVE_LLVM >= 0x0208
201   InitializeNativeTargetAsmPrinter();
202#elif defined(PIPE_ARCH_X86) || defined(PIPE_ARCH_X86_64)
203   LLVMInitializeX86AsmPrinter();
204#elif defined(PIPE_ARCH_ARM)
205   LLVMInitializeARMAsmPrinter();
206#elif defined(PIPE_ARCH_PPC)
207   LLVMInitializePowerPCAsmPrinter();
208#endif
209
210#if defined(PIPE_ARCH_X86) || defined(PIPE_ARCH_X86_64)
211   LLVMInitializeX86Disassembler();
212#elif defined(PIPE_ARCH_ARM)
213   LLVMInitializeARMDisassembler();
214#endif
215
216#if HAVE_LLVM >= 0x0300
217   OwningPtr<const MCAsmInfo> AsmInfo(T->createMCAsmInfo(Triple));
218#else
219   OwningPtr<const MCAsmInfo> AsmInfo(T->createAsmInfo(Triple));
220#endif
221
222   if (!AsmInfo) {
223      debug_printf("error: no assembly info for target %s\n", Triple.c_str());
224      return;
225   }
226
227#if HAVE_LLVM >= 0x0300
228   const MCSubtargetInfo *STI = T->createMCSubtargetInfo(Triple, sys::getHostCPUName(), "");
229   OwningPtr<const MCDisassembler> DisAsm(T->createMCDisassembler(*STI));
230#else
231   OwningPtr<const MCDisassembler> DisAsm(T->createMCDisassembler());
232#endif
233   if (!DisAsm) {
234      debug_printf("error: no disassembler for target %s\n", Triple.c_str());
235      return;
236   }
237
238   raw_debug_ostream Out;
239
240#if HAVE_LLVM >= 0x0300
241   unsigned int AsmPrinterVariant = AsmInfo->getAssemblerDialect();
242#else
243   int AsmPrinterVariant = AsmInfo->getAssemblerDialect();
244#endif
245
246#if HAVE_LLVM >= 0x0300
247   OwningPtr<MCInstPrinter> Printer(
248         T->createMCInstPrinter(AsmPrinterVariant, *AsmInfo, *STI));
249#elif HAVE_LLVM >= 0x0208
250   OwningPtr<MCInstPrinter> Printer(
251         T->createMCInstPrinter(AsmPrinterVariant, *AsmInfo));
252#else
253   OwningPtr<MCInstPrinter> Printer(
254         T->createMCInstPrinter(AsmPrinterVariant, *AsmInfo, Out));
255#endif
256   if (!Printer) {
257      debug_printf("error: no instruction printer for target %s\n", Triple.c_str());
258      return;
259   }
260
261#if HAVE_LLVM >= 0x0301
262   TargetOptions options;
263#if defined(DEBUG)
264   options.JITEmitDebugInfo = true;
265#endif
266#if defined(PIPE_ARCH_X86)
267   options.StackAlignmentOverride = 4;
268#endif
269#if defined(DEBUG) || defined(PROFILE)
270   options.NoFramePointerElim = true;
271#endif
272   TargetMachine *TM = T->createTargetMachine(Triple, sys::getHostCPUName(), "", options);
273#elif HAVE_LLVM == 0x0300
274   TargetMachine *TM = T->createTargetMachine(Triple, sys::getHostCPUName(), "");
275#else
276   TargetMachine *TM = T->createTargetMachine(Triple, "");
277#endif
278
279   const TargetInstrInfo *TII = TM->getInstrInfo();
280
281   /*
282    * Wrap the data in a MemoryObject
283    */
284   BufferMemoryObject memoryObject((const uint8_t *)bytes, extent);
285
286   uint64_t pc;
287   pc = 0;
288   while (true) {
289      MCInst Inst;
290      uint64_t Size;
291
292      /*
293       * Print address.  We use addresses relative to the start of the function,
294       * so that between runs.
295       */
296
297      debug_printf("%6lu:\t", (unsigned long)pc);
298
299      if (!DisAsm->getInstruction(Inst, Size, memoryObject,
300                                 pc,
301#if HAVE_LLVM >= 0x0300
302				  nulls(), nulls())) {
303#else
304				  nulls())) {
305#endif
306         debug_printf("invalid\n");
307         pc += 1;
308      }
309
310      /*
311       * Output the bytes in hexidecimal format.
312       */
313
314      if (0) {
315         unsigned i;
316         for (i = 0; i < Size; ++i) {
317            debug_printf("%02x ", ((const uint8_t*)bytes)[pc + i]);
318         }
319         for (; i < 16; ++i) {
320            debug_printf("   ");
321         }
322      }
323
324      /*
325       * Print the instruction.
326       */
327
328#if HAVE_LLVM >= 0x0300
329      Printer->printInst(&Inst, Out, "");
330#elif HAVE_LLVM >= 0x208
331      Printer->printInst(&Inst, Out);
332#else
333      Printer->printInst(&Inst);
334#endif
335      Out.flush();
336
337      /*
338       * Advance.
339       */
340
341      pc += Size;
342
343#if HAVE_LLVM >= 0x0300
344      const MCInstrDesc &TID = TII->get(Inst.getOpcode());
345#else
346      const TargetInstrDesc &TID = TII->get(Inst.getOpcode());
347#endif
348
349      /*
350       * Keep track of forward jumps to a nearby address.
351       */
352
353      if (TID.isBranch()) {
354         for (unsigned i = 0; i < Inst.getNumOperands(); ++i) {
355            const MCOperand &operand = Inst.getOperand(i);
356            if (operand.isImm()) {
357               uint64_t jump;
358
359               /*
360                * FIXME: Handle both relative and absolute addresses correctly.
361                * EDInstInfo actually has this info, but operandTypes and
362                * operandFlags enums are not exposed in the public interface.
363                */
364
365               if (1) {
366                  /*
367                   * PC relative addr.
368                   */
369
370                  jump = pc + operand.getImm();
371               } else {
372                  /*
373                   * Absolute addr.
374                   */
375
376                  jump = (uint64_t)operand.getImm();
377               }
378
379               /*
380                * Output the address relative to the function start, given
381                * that MC will print the addresses relative the current pc.
382                */
383               debug_printf("\t\t; %lu", (unsigned long)jump);
384
385               /*
386                * Ignore far jumps given it could be actually a tail return to
387                * a random address.
388                */
389
390               if (jump > max_pc &&
391                   jump < extent) {
392                  max_pc = jump;
393               }
394            }
395         }
396      }
397
398      debug_printf("\n");
399
400      /*
401       * Stop disassembling on return statements, if there is no record of a
402       * jump to a successive address.
403       */
404
405      if (TID.isReturn()) {
406         if (pc > max_pc) {
407            break;
408         }
409      }
410   }
411
412   /*
413    * Print GDB command, useful to verify output.
414    */
415
416   if (0) {
417      debug_printf("disassemble %p %p\n", bytes, bytes + pc);
418   }
419
420   debug_printf("\n");
421#else /* HAVE_LLVM < 0x0207 */
422   (void)func;
423#endif /* HAVE_LLVM < 0x0207 */
424}
425
426