disassembler.cc revision f87a203d89e1bbb6708282e0b64dbd13d59b723d 
1// Copyright 2006-2008 the V8 project authors. All rights reserved.
2// Redistribution and use in source and binary forms, with or without
3// modification, are permitted provided that the following conditions are
4// met:
5//
6//     * Redistributions of source code must retain the above copyright
7//       notice, this list of conditions and the following disclaimer.
8//     * Redistributions in binary form must reproduce the above
9//       copyright notice, this list of conditions and the following
10//       disclaimer in the documentation and/or other materials provided
11//       with the distribution.
12//     * Neither the name of Google Inc. nor the names of its
13//       contributors may be used to endorse or promote products derived
14//       from this software without specific prior written permission.
15//
16// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27
28#include "v8.h"
29
30#include "code-stubs.h"
31#include "codegen-inl.h"
32#include "debug.h"
33#include "disasm.h"
34#include "disassembler.h"
35#include "macro-assembler.h"
36#include "serialize.h"
37#include "string-stream.h"
38
39namespace v8 {
40namespace internal {
41
42#ifdef ENABLE_DISASSEMBLER
43
44void Disassembler::Dump(FILE* f, byte* begin, byte* end) {
45  for (byte* pc = begin; pc < end; pc++) {
46    if (f == NULL) {
47      PrintF("%" V8PRIxPTR "  %4" V8PRIdPTR "  %02x\n",
48             reinterpret_cast<intptr_t>(pc),
49             pc - begin,
50             *pc);
51    } else {
52      fprintf(f, "%" V8PRIxPTR "  %4" V8PRIdPTR "  %02x\n",
53              reinterpret_cast<uintptr_t>(pc), pc - begin, *pc);
54    }
55  }
56}
57
58
59class V8NameConverter: public disasm::NameConverter {
60 public:
61  explicit V8NameConverter(Code* code) : code_(code) {}
62  virtual const char* NameOfAddress(byte* pc) const;
63  virtual const char* NameInCode(byte* addr) const;
64  Code* code() const { return code_; }
65 private:
66  Code* code_;
67};
68
69
70const char* V8NameConverter::NameOfAddress(byte* pc) const {
71  static v8::internal::EmbeddedVector<char, 128> buffer;
72
73  const char* name = Builtins::Lookup(pc);
74  if (name != NULL) {
75    OS::SNPrintF(buffer, "%s  (%p)", name, pc);
76    return buffer.start();
77  }
78
79  if (code_ != NULL) {
80    int offs = static_cast<int>(pc - code_->instruction_start());
81    // print as code offset, if it seems reasonable
82    if (0 <= offs && offs < code_->instruction_size()) {
83      OS::SNPrintF(buffer, "%d  (%p)", offs, pc);
84      return buffer.start();
85    }
86  }
87
88  return disasm::NameConverter::NameOfAddress(pc);
89}
90
91
92const char* V8NameConverter::NameInCode(byte* addr) const {
93  // The V8NameConverter is used for well known code, so we can "safely"
94  // dereference pointers in generated code.
95  return (code_ != NULL) ? reinterpret_cast<const char*>(addr) : "";
96}
97
98
99static void DumpBuffer(FILE* f, char* buff) {
100  if (f == NULL) {
101    PrintF("%s", buff);
102  } else {
103    fprintf(f, "%s", buff);
104  }
105}
106
107static const int kOutBufferSize = 2048 + String::kMaxShortPrintLength;
108static const int kRelocInfoPosition = 57;
109
110static int DecodeIt(FILE* f,
111                    const V8NameConverter& converter,
112                    byte* begin,
113                    byte* end) {
114  NoHandleAllocation ha;
115  AssertNoAllocation no_alloc;
116  ExternalReferenceEncoder ref_encoder;
117
118  v8::internal::EmbeddedVector<char, 128> decode_buffer;
119  v8::internal::EmbeddedVector<char, kOutBufferSize> out_buffer;
120  byte* pc = begin;
121  disasm::Disassembler d(converter);
122  RelocIterator* it = NULL;
123  if (converter.code() != NULL) {
124    it = new RelocIterator(converter.code());
125  } else {
126    // No relocation information when printing code stubs.
127  }
128  int constants = -1;  // no constants being decoded at the start
129
130  while (pc < end) {
131    // First decode instruction so that we know its length.
132    byte* prev_pc = pc;
133    if (constants > 0) {
134      OS::SNPrintF(decode_buffer,
135                   "%08x       constant",
136                   *reinterpret_cast<int32_t*>(pc));
137      constants--;
138      pc += 4;
139    } else {
140      int num_const = d.ConstantPoolSizeAt(pc);
141      if (num_const >= 0) {
142        OS::SNPrintF(decode_buffer,
143                     "%08x       constant pool begin",
144                     *reinterpret_cast<int32_t*>(pc));
145        constants = num_const;
146        pc += 4;
147      } else if (it != NULL && !it->done() && it->rinfo()->pc() == pc &&
148          it->rinfo()->rmode() == RelocInfo::INTERNAL_REFERENCE) {
149        // raw pointer embedded in code stream, e.g., jump table
150        byte* ptr = *reinterpret_cast<byte**>(pc);
151        OS::SNPrintF(decode_buffer,
152                     "%08" V8PRIxPTR "      jump table entry %4" V8PRIdPTR,
153                     ptr,
154                     ptr - begin);
155        pc += 4;
156      } else {
157        decode_buffer[0] = '\0';
158        pc += d.InstructionDecode(decode_buffer, pc);
159      }
160    }
161
162    // Collect RelocInfo for this instruction (prev_pc .. pc-1)
163    List<const char*> comments(4);
164    List<byte*> pcs(1);
165    List<RelocInfo::Mode> rmodes(1);
166    List<intptr_t> datas(1);
167    if (it != NULL) {
168      while (!it->done() && it->rinfo()->pc() < pc) {
169        if (RelocInfo::IsComment(it->rinfo()->rmode())) {
170          // For comments just collect the text.
171          comments.Add(reinterpret_cast<const char*>(it->rinfo()->data()));
172        } else {
173          // For other reloc info collect all data.
174          pcs.Add(it->rinfo()->pc());
175          rmodes.Add(it->rinfo()->rmode());
176          datas.Add(it->rinfo()->data());
177        }
178        it->next();
179      }
180    }
181
182    StringBuilder out(out_buffer.start(), out_buffer.length());
183
184    // Comments.
185    for (int i = 0; i < comments.length(); i++) {
186      out.AddFormatted("                  %s\n", comments[i]);
187    }
188
189    // Write out comments, resets outp so that we can format the next line.
190    DumpBuffer(f, out.Finalize());
191    out.Reset();
192
193    // Instruction address and instruction offset.
194    out.AddFormatted("%p  %4d  ", prev_pc, prev_pc - begin);
195
196    // Instruction.
197    out.AddFormatted("%s", decode_buffer.start());
198
199    // Print all the reloc info for this instruction which are not comments.
200    for (int i = 0; i < pcs.length(); i++) {
201      // Put together the reloc info
202      RelocInfo relocinfo(pcs[i], rmodes[i], datas[i]);
203
204      // Indent the printing of the reloc info.
205      if (i == 0) {
206        // The first reloc info is printed after the disassembled instruction.
207        out.AddPadding(' ', kRelocInfoPosition - out.position());
208      } else {
209        // Additional reloc infos are printed on separate lines.
210        out.AddFormatted("\n");
211        out.AddPadding(' ', kRelocInfoPosition);
212      }
213
214      RelocInfo::Mode rmode = relocinfo.rmode();
215      if (RelocInfo::IsPosition(rmode)) {
216        if (RelocInfo::IsStatementPosition(rmode)) {
217          out.AddFormatted("    ;; debug: statement %d", relocinfo.data());
218        } else {
219          out.AddFormatted("    ;; debug: position %d", relocinfo.data());
220        }
221      } else if (rmode == RelocInfo::EMBEDDED_OBJECT) {
222        HeapStringAllocator allocator;
223        StringStream accumulator(&allocator);
224        relocinfo.target_object()->ShortPrint(&accumulator);
225        SmartPointer<const char> obj_name = accumulator.ToCString();
226        out.AddFormatted("    ;; object: %s", *obj_name);
227      } else if (rmode == RelocInfo::EXTERNAL_REFERENCE) {
228        const char* reference_name =
229            ref_encoder.NameOfAddress(*relocinfo.target_reference_address());
230        out.AddFormatted("    ;; external reference (%s)", reference_name);
231      } else if (RelocInfo::IsCodeTarget(rmode)) {
232        out.AddFormatted("    ;; code:");
233        if (rmode == RelocInfo::CONSTRUCT_CALL) {
234          out.AddFormatted(" constructor,");
235        }
236        Code* code = Code::GetCodeFromTargetAddress(relocinfo.target_address());
237        Code::Kind kind = code->kind();
238        if (code->is_inline_cache_stub()) {
239          if (rmode == RelocInfo::CODE_TARGET_CONTEXT) {
240            out.AddFormatted(" contextual,");
241          }
242          InlineCacheState ic_state = code->ic_state();
243          out.AddFormatted(" %s, %s", Code::Kind2String(kind),
244              Code::ICState2String(ic_state));
245          if (ic_state == MONOMORPHIC) {
246            PropertyType type = code->type();
247            out.AddFormatted(", %s", Code::PropertyType2String(type));
248          }
249          if (code->ic_in_loop() == IN_LOOP) {
250            out.AddFormatted(", in_loop");
251          }
252          if (kind == Code::CALL_IC || kind == Code::KEYED_CALL_IC) {
253            out.AddFormatted(", argc = %d", code->arguments_count());
254          }
255        } else if (kind == Code::STUB) {
256          // Reverse lookup required as the minor key cannot be retrieved
257          // from the code object.
258          Object* obj = Heap::code_stubs()->SlowReverseLookup(code);
259          if (obj != Heap::undefined_value()) {
260            ASSERT(obj->IsSmi());
261            // Get the STUB key and extract major and minor key.
262            uint32_t key = Smi::cast(obj)->value();
263            uint32_t minor_key = CodeStub::MinorKeyFromKey(key);
264            CodeStub::Major major_key = CodeStub::GetMajorKey(code);
265            ASSERT(major_key == CodeStub::MajorKeyFromKey(key));
266            out.AddFormatted(" %s, %s, ",
267                             Code::Kind2String(kind),
268                             CodeStub::MajorName(major_key, false));
269            switch (major_key) {
270              case CodeStub::CallFunction:
271                out.AddFormatted("argc = %d", minor_key);
272                break;
273            default:
274                out.AddFormatted("minor: %d", minor_key);
275            }
276          }
277        } else {
278          out.AddFormatted(" %s", Code::Kind2String(kind));
279        }
280      } else {
281        out.AddFormatted("    ;; %s", RelocInfo::RelocModeName(rmode));
282      }
283    }
284    out.AddString("\n");
285    DumpBuffer(f, out.Finalize());
286    out.Reset();
287  }
288
289  delete it;
290  return static_cast<int>(pc - begin);
291}
292
293
294int Disassembler::Decode(FILE* f, byte* begin, byte* end) {
295  V8NameConverter defaultConverter(NULL);
296  return DecodeIt(f, defaultConverter, begin, end);
297}
298
299
300// Called by Code::CodePrint.
301void Disassembler::Decode(FILE* f, Code* code) {
302  byte* begin = Code::cast(code)->instruction_start();
303  byte* end = begin + Code::cast(code)->instruction_size();
304  V8NameConverter v8NameConverter(code);
305  DecodeIt(f, v8NameConverter, begin, end);
306}
307
308#else  // ENABLE_DISASSEMBLER
309
310void Disassembler::Dump(FILE* f, byte* begin, byte* end) {}
311int Disassembler::Decode(FILE* f, byte* begin, byte* end) { return 0; }
312void Disassembler::Decode(FILE* f, Code* code) {}
313
314#endif  // ENABLE_DISASSEMBLER
315
316} }  // namespace v8::internal
317