lp_bld_debug.cpp revision 4f513002f65c629576252b34efedf3c8c4531dfd 
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
87#if HAVE_LLVM >= 0x207
88   uint64_t current_pos() const { return pos; }
89   size_t preferred_buffer_size() const { return 512; }
90#else
91   uint64_t current_pos() { return pos; }
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 HAVE_LLVM >= 0x0301
211   InitializeNativeTargetDisassembler();
212#elif defined(PIPE_ARCH_X86) || defined(PIPE_ARCH_X86_64)
213   LLVMInitializeX86Disassembler();
214#elif defined(PIPE_ARCH_ARM)
215   LLVMInitializeARMDisassembler();
216#endif
217
218#if HAVE_LLVM >= 0x0300
219   OwningPtr<const MCAsmInfo> AsmInfo(T->createMCAsmInfo(Triple));
220#else
221   OwningPtr<const MCAsmInfo> AsmInfo(T->createAsmInfo(Triple));
222#endif
223
224   if (!AsmInfo) {
225      debug_printf("error: no assembly info for target %s\n", Triple.c_str());
226      return;
227   }
228
229#if HAVE_LLVM >= 0x0300
230   const MCSubtargetInfo *STI = T->createMCSubtargetInfo(Triple, sys::getHostCPUName(), "");
231   OwningPtr<const MCDisassembler> DisAsm(T->createMCDisassembler(*STI));
232#else
233   OwningPtr<const MCDisassembler> DisAsm(T->createMCDisassembler());
234#endif
235   if (!DisAsm) {
236      debug_printf("error: no disassembler for target %s\n", Triple.c_str());
237      return;
238   }
239
240   raw_debug_ostream Out;
241
242#if HAVE_LLVM >= 0x0300
243   unsigned int AsmPrinterVariant = AsmInfo->getAssemblerDialect();
244#else
245   int AsmPrinterVariant = AsmInfo->getAssemblerDialect();
246#endif
247
248#if HAVE_LLVM >= 0x0301
249   OwningPtr<const MCRegisterInfo> MRI(T->createMCRegInfo(Triple));
250   if (!MRI) {
251      debug_printf("error: no register info for target %s\n", Triple.c_str());
252      return;
253   }
254
255   OwningPtr<const MCInstrInfo> MII(T->createMCInstrInfo());
256   if (!MII) {
257      debug_printf("error: no instruction info for target %s\n", Triple.c_str());
258      return;
259   }
260#endif
261
262#if HAVE_LLVM >= 0x0301
263   OwningPtr<MCInstPrinter> Printer(
264         T->createMCInstPrinter(AsmPrinterVariant, *AsmInfo, *MII, *MRI, *STI));
265#elif HAVE_LLVM == 0x0300
266   OwningPtr<MCInstPrinter> Printer(
267         T->createMCInstPrinter(AsmPrinterVariant, *AsmInfo, *STI));
268#elif HAVE_LLVM >= 0x0208
269   OwningPtr<MCInstPrinter> Printer(
270         T->createMCInstPrinter(AsmPrinterVariant, *AsmInfo));
271#else
272   OwningPtr<MCInstPrinter> Printer(
273         T->createMCInstPrinter(AsmPrinterVariant, *AsmInfo, Out));
274#endif
275   if (!Printer) {
276      debug_printf("error: no instruction printer for target %s\n", Triple.c_str());
277      return;
278   }
279
280#if HAVE_LLVM >= 0x0301
281   TargetOptions options;
282#if defined(DEBUG)
283   options.JITEmitDebugInfo = true;
284#endif
285#if defined(PIPE_ARCH_X86)
286   options.StackAlignmentOverride = 4;
287#endif
288#if defined(DEBUG) || defined(PROFILE)
289   options.NoFramePointerElim = true;
290#endif
291   TargetMachine *TM = T->createTargetMachine(Triple, sys::getHostCPUName(), "", options);
292#elif HAVE_LLVM == 0x0300
293   TargetMachine *TM = T->createTargetMachine(Triple, sys::getHostCPUName(), "");
294#else
295   TargetMachine *TM = T->createTargetMachine(Triple, "");
296#endif
297
298   const TargetInstrInfo *TII = TM->getInstrInfo();
299
300   /*
301    * Wrap the data in a MemoryObject
302    */
303   BufferMemoryObject memoryObject((const uint8_t *)bytes, extent);
304
305   uint64_t pc;
306   pc = 0;
307   while (true) {
308      MCInst Inst;
309      uint64_t Size;
310
311      /*
312       * Print address.  We use addresses relative to the start of the function,
313       * so that between runs.
314       */
315
316      debug_printf("%6lu:\t", (unsigned long)pc);
317
318      if (!DisAsm->getInstruction(Inst, Size, memoryObject,
319                                 pc,
320#if HAVE_LLVM >= 0x0300
321				  nulls(), nulls())) {
322#else
323				  nulls())) {
324#endif
325         debug_printf("invalid\n");
326         pc += 1;
327      }
328
329      /*
330       * Output the bytes in hexidecimal format.
331       */
332
333      if (0) {
334         unsigned i;
335         for (i = 0; i < Size; ++i) {
336            debug_printf("%02x ", ((const uint8_t*)bytes)[pc + i]);
337         }
338         for (; i < 16; ++i) {
339            debug_printf("   ");
340         }
341      }
342
343      /*
344       * Print the instruction.
345       */
346
347#if HAVE_LLVM >= 0x0300
348      Printer->printInst(&Inst, Out, "");
349#elif HAVE_LLVM >= 0x208
350      Printer->printInst(&Inst, Out);
351#else
352      Printer->printInst(&Inst);
353#endif
354      Out.flush();
355
356      /*
357       * Advance.
358       */
359
360      pc += Size;
361
362#if HAVE_LLVM >= 0x0300
363      const MCInstrDesc &TID = TII->get(Inst.getOpcode());
364#else
365      const TargetInstrDesc &TID = TII->get(Inst.getOpcode());
366#endif
367
368      /*
369       * Keep track of forward jumps to a nearby address.
370       */
371
372      if (TID.isBranch()) {
373         for (unsigned i = 0; i < Inst.getNumOperands(); ++i) {
374            const MCOperand &operand = Inst.getOperand(i);
375            if (operand.isImm()) {
376               uint64_t jump;
377
378               /*
379                * FIXME: Handle both relative and absolute addresses correctly.
380                * EDInstInfo actually has this info, but operandTypes and
381                * operandFlags enums are not exposed in the public interface.
382                */
383
384               if (1) {
385                  /*
386                   * PC relative addr.
387                   */
388
389                  jump = pc + operand.getImm();
390               } else {
391                  /*
392                   * Absolute addr.
393                   */
394
395                  jump = (uint64_t)operand.getImm();
396               }
397
398               /*
399                * Output the address relative to the function start, given
400                * that MC will print the addresses relative the current pc.
401                */
402               debug_printf("\t\t; %lu", (unsigned long)jump);
403
404               /*
405                * Ignore far jumps given it could be actually a tail return to
406                * a random address.
407                */
408
409               if (jump > max_pc &&
410                   jump < extent) {
411                  max_pc = jump;
412               }
413            }
414         }
415      }
416
417      debug_printf("\n");
418
419      /*
420       * Stop disassembling on return statements, if there is no record of a
421       * jump to a successive address.
422       */
423
424      if (TID.isReturn()) {
425         if (pc > max_pc) {
426            break;
427         }
428      }
429   }
430
431   /*
432    * Print GDB command, useful to verify output.
433    */
434
435   if (0) {
436      debug_printf("disassemble %p %p\n", bytes, bytes + pc);
437   }
438
439   debug_printf("\n");
440#else /* HAVE_LLVM < 0x0207 */
441   (void)func;
442#endif /* HAVE_LLVM < 0x0207 */
443}
444
445