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#else /* HAVE_LLVM < 0x0300 */
39#include <llvm/Target/TargetRegistry.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#if HAVE_LLVM >= 0x0301
55#include <llvm/MC/MCRegisterInfo.h>
56#endif /* HAVE_LLVM >= 0x0301 */
57
58#include "util/u_math.h"
59#include "util/u_debug.h"
60
61#include "lp_bld_debug.h"
62
63
64
65/**
66 * Check alignment.
67 *
68 * It is important that this check is not implemented as a macro or inlined
69 * function, as the compiler assumptions in respect to alignment of global
70 * and stack variables would often make the check a no op, defeating the
71 * whole purpose of the exercise.
72 */
73extern "C" boolean
74lp_check_alignment(const void *ptr, unsigned alignment)
75{
76   assert(util_is_power_of_two(alignment));
77   return ((uintptr_t)ptr & (alignment - 1)) == 0;
78}
79
80
81class raw_debug_ostream :
82   public llvm::raw_ostream
83{
84private:
85   uint64_t pos;
86
87public:
88   raw_debug_ostream() : pos(0) { }
89
90   void write_impl(const char *Ptr, size_t Size);
91
92#if HAVE_LLVM >= 0x207
93   uint64_t current_pos() const { return pos; }
94   size_t preferred_buffer_size() const { return 512; }
95#else
96   uint64_t current_pos() { return pos; }
97   size_t preferred_buffer_size() { return 512; }
98#endif
99};
100
101
102void
103raw_debug_ostream::write_impl(const char *Ptr, size_t Size)
104{
105   if (Size > 0) {
106      char *lastPtr = (char *)&Ptr[Size];
107      char last = *lastPtr;
108      *lastPtr = 0;
109      _debug_printf("%*s", Size, Ptr);
110      *lastPtr = last;
111      pos += Size;
112   }
113}
114
115
116/**
117 * Same as LLVMDumpValue, but through our debugging channels.
118 */
119extern "C" void
120lp_debug_dump_value(LLVMValueRef value)
121{
122#if (defined(PIPE_OS_WINDOWS) && !defined(PIPE_CC_MSVC)) || defined(PIPE_OS_EMBDDED)
123   raw_debug_ostream os;
124   llvm::unwrap(value)->print(os);
125   os.flush();
126#else
127   LLVMDumpValue(value);
128#endif
129}
130
131
132#if HAVE_LLVM >= 0x0207
133/*
134 * MemoryObject wrapper around a buffer of memory, to be used by MC
135 * disassembler.
136 */
137class BufferMemoryObject:
138   public llvm::MemoryObject
139{
140private:
141   const uint8_t *Bytes;
142   uint64_t Length;
143public:
144   BufferMemoryObject(const uint8_t *bytes, uint64_t length) :
145      Bytes(bytes), Length(length)
146   {
147   }
148
149   uint64_t getBase() const
150   {
151      return 0;
152   }
153
154   uint64_t getExtent() const
155   {
156      return Length;
157   }
158
159   int readByte(uint64_t addr, uint8_t *byte) const
160   {
161      if (addr > getExtent())
162         return -1;
163      *byte = Bytes[addr];
164      return 0;
165   }
166};
167#endif /* HAVE_LLVM >= 0x0207 */
168
169
170/*
171 * Disassemble a function, using the LLVM MC disassembler.
172 *
173 * See also:
174 * - http://blog.llvm.org/2010/01/x86-disassembler.html
175 * - http://blog.llvm.org/2010/04/intro-to-llvm-mc-project.html
176 */
177extern "C" void
178lp_disassemble(const void* func)
179{
180#if HAVE_LLVM >= 0x0207
181   using namespace llvm;
182
183   const uint8_t *bytes = (const uint8_t *)func;
184
185   /*
186    * Limit disassembly to this extent
187    */
188   const uint64_t extent = 96 * 1024;
189
190   uint64_t max_pc = 0;
191
192   /*
193    * Initialize all used objects.
194    */
195
196#if HAVE_LLVM >= 0x0301
197   std::string Triple = sys::getDefaultTargetTriple();
198#else
199   std::string Triple = sys::getHostTriple();
200#endif
201
202   std::string Error;
203   const Target *T = TargetRegistry::lookupTarget(Triple, Error);
204
205#if HAVE_LLVM >= 0x0300
206   OwningPtr<const MCAsmInfo> AsmInfo(T->createMCAsmInfo(Triple));
207#else
208   OwningPtr<const MCAsmInfo> AsmInfo(T->createAsmInfo(Triple));
209#endif
210
211   if (!AsmInfo) {
212      debug_printf("error: no assembly info for target %s\n", Triple.c_str());
213      return;
214   }
215
216#if HAVE_LLVM >= 0x0300
217   const MCSubtargetInfo *STI = T->createMCSubtargetInfo(Triple, sys::getHostCPUName(), "");
218   OwningPtr<const MCDisassembler> DisAsm(T->createMCDisassembler(*STI));
219#else
220   OwningPtr<const MCDisassembler> DisAsm(T->createMCDisassembler());
221#endif
222   if (!DisAsm) {
223      debug_printf("error: no disassembler for target %s\n", Triple.c_str());
224      return;
225   }
226
227   raw_debug_ostream Out;
228
229#if HAVE_LLVM >= 0x0300
230   unsigned int AsmPrinterVariant = AsmInfo->getAssemblerDialect();
231#else
232   int AsmPrinterVariant = AsmInfo->getAssemblerDialect();
233#endif
234
235#if HAVE_LLVM >= 0x0301
236   OwningPtr<const MCRegisterInfo> MRI(T->createMCRegInfo(Triple));
237   if (!MRI) {
238      debug_printf("error: no register info for target %s\n", Triple.c_str());
239      return;
240   }
241
242   OwningPtr<const MCInstrInfo> MII(T->createMCInstrInfo());
243   if (!MII) {
244      debug_printf("error: no instruction info for target %s\n", Triple.c_str());
245      return;
246   }
247#endif
248
249#if HAVE_LLVM >= 0x0301
250   OwningPtr<MCInstPrinter> Printer(
251         T->createMCInstPrinter(AsmPrinterVariant, *AsmInfo, *MII, *MRI, *STI));
252#elif HAVE_LLVM == 0x0300
253   OwningPtr<MCInstPrinter> Printer(
254         T->createMCInstPrinter(AsmPrinterVariant, *AsmInfo, *STI));
255#elif HAVE_LLVM >= 0x0208
256   OwningPtr<MCInstPrinter> Printer(
257         T->createMCInstPrinter(AsmPrinterVariant, *AsmInfo));
258#else
259   OwningPtr<MCInstPrinter> Printer(
260         T->createMCInstPrinter(AsmPrinterVariant, *AsmInfo, Out));
261#endif
262   if (!Printer) {
263      debug_printf("error: no instruction printer for target %s\n", Triple.c_str());
264      return;
265   }
266
267#if HAVE_LLVM >= 0x0301
268   TargetOptions options;
269#if defined(DEBUG)
270   options.JITEmitDebugInfo = true;
271#endif
272#if defined(PIPE_ARCH_X86)
273   options.StackAlignmentOverride = 4;
274#endif
275#if defined(DEBUG) || defined(PROFILE)
276   options.NoFramePointerElim = true;
277#endif
278   TargetMachine *TM = T->createTargetMachine(Triple, sys::getHostCPUName(), "", options);
279#elif HAVE_LLVM == 0x0300
280   TargetMachine *TM = T->createTargetMachine(Triple, sys::getHostCPUName(), "");
281#else
282   TargetMachine *TM = T->createTargetMachine(Triple, "");
283#endif
284
285   const TargetInstrInfo *TII = TM->getInstrInfo();
286
287   /*
288    * Wrap the data in a MemoryObject
289    */
290   BufferMemoryObject memoryObject((const uint8_t *)bytes, extent);
291
292   uint64_t pc;
293   pc = 0;
294   while (true) {
295      MCInst Inst;
296      uint64_t Size;
297
298      /*
299       * Print address.  We use addresses relative to the start of the function,
300       * so that between runs.
301       */
302
303      debug_printf("%6lu:\t", (unsigned long)pc);
304
305      if (!DisAsm->getInstruction(Inst, Size, memoryObject,
306                                 pc,
307#if HAVE_LLVM >= 0x0300
308				  nulls(), nulls())) {
309#else
310				  nulls())) {
311#endif
312         debug_printf("invalid\n");
313         pc += 1;
314      }
315
316      /*
317       * Output the bytes in hexidecimal format.
318       */
319
320      if (0) {
321         unsigned i;
322         for (i = 0; i < Size; ++i) {
323            debug_printf("%02x ", ((const uint8_t*)bytes)[pc + i]);
324         }
325         for (; i < 16; ++i) {
326            debug_printf("   ");
327         }
328      }
329
330      /*
331       * Print the instruction.
332       */
333
334#if HAVE_LLVM >= 0x0300
335      Printer->printInst(&Inst, Out, "");
336#elif HAVE_LLVM >= 0x208
337      Printer->printInst(&Inst, Out);
338#else
339      Printer->printInst(&Inst);
340#endif
341      Out.flush();
342
343      /*
344       * Advance.
345       */
346
347      pc += Size;
348
349#if HAVE_LLVM >= 0x0300
350      const MCInstrDesc &TID = TII->get(Inst.getOpcode());
351#else
352      const TargetInstrDesc &TID = TII->get(Inst.getOpcode());
353#endif
354
355      /*
356       * Keep track of forward jumps to a nearby address.
357       */
358
359      if (TID.isBranch()) {
360         for (unsigned i = 0; i < Inst.getNumOperands(); ++i) {
361            const MCOperand &operand = Inst.getOperand(i);
362            if (operand.isImm()) {
363               uint64_t jump;
364
365               /*
366                * FIXME: Handle both relative and absolute addresses correctly.
367                * EDInstInfo actually has this info, but operandTypes and
368                * operandFlags enums are not exposed in the public interface.
369                */
370
371               if (1) {
372                  /*
373                   * PC relative addr.
374                   */
375
376                  jump = pc + operand.getImm();
377               } else {
378                  /*
379                   * Absolute addr.
380                   */
381
382                  jump = (uint64_t)operand.getImm();
383               }
384
385               /*
386                * Output the address relative to the function start, given
387                * that MC will print the addresses relative the current pc.
388                */
389               debug_printf("\t\t; %lu", (unsigned long)jump);
390
391               /*
392                * Ignore far jumps given it could be actually a tail return to
393                * a random address.
394                */
395
396               if (jump > max_pc &&
397                   jump < extent) {
398                  max_pc = jump;
399               }
400            }
401         }
402      }
403
404      debug_printf("\n");
405
406      /*
407       * Stop disassembling on return statements, if there is no record of a
408       * jump to a successive address.
409       */
410
411      if (TID.isReturn()) {
412         if (pc > max_pc) {
413            break;
414         }
415      }
416   }
417
418   /*
419    * Print GDB command, useful to verify output.
420    */
421
422   if (0) {
423      debug_printf("disassemble %p %p\n", bytes, bytes + pc);
424   }
425
426   debug_printf("\n");
427#else /* HAVE_LLVM < 0x0207 */
428   (void)func;
429#endif /* HAVE_LLVM < 0x0207 */
430}
431
432