1 //===-- DWARFExpression.cpp -------------------------------------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "lldb/Expression/DWARFExpression.h"
11 
12 // C Includes
13 #include <inttypes.h>
14 
15 // C++ Includes
16 #include <vector>
17 
18 #include "lldb/Core/DataEncoder.h"
19 #include "lldb/Core/dwarf.h"
20 #include "lldb/Core/Log.h"
21 #include "lldb/Core/RegisterValue.h"
22 #include "lldb/Core/StreamString.h"
23 #include "lldb/Core/Scalar.h"
24 #include "lldb/Core/Value.h"
25 #include "lldb/Core/VMRange.h"
26 
27 #include "lldb/Expression/ClangExpressionDeclMap.h"
28 #include "lldb/Expression/ClangExpressionVariable.h"
29 
30 #include "lldb/Host/Endian.h"
31 #include "lldb/Host/Host.h"
32 
33 #include "lldb/lldb-private-log.h"
34 
35 #include "lldb/Target/ABI.h"
36 #include "lldb/Target/ExecutionContext.h"
37 #include "lldb/Target/Process.h"
38 #include "lldb/Target/RegisterContext.h"
39 #include "lldb/Target/StackFrame.h"
40 #include "lldb/Target/StackID.h"
41 #include "lldb/Target/Thread.h"
42 
43 using namespace lldb;
44 using namespace lldb_private;
45 
46 // TODO- why is this also defined (in a better way) in DWARFDefines.cpp?
47 const char *
48 DW_OP_value_to_name (uint32_t val)
49 {
50   static char invalid[100];
51   switch (val) {
52     case 0x03: return "DW_OP_addr";
53     case 0x06: return "DW_OP_deref";
54     case 0x08: return "DW_OP_const1u";
55     case 0x09: return "DW_OP_const1s";
56     case 0x0a: return "DW_OP_const2u";
57     case 0x0b: return "DW_OP_const2s";
58     case 0x0c: return "DW_OP_const4u";
59     case 0x0d: return "DW_OP_const4s";
60     case 0x0e: return "DW_OP_const8u";
61     case 0x0f: return "DW_OP_const8s";
62     case 0x10: return "DW_OP_constu";
63     case 0x11: return "DW_OP_consts";
64     case 0x12: return "DW_OP_dup";
65     case 0x13: return "DW_OP_drop";
66     case 0x14: return "DW_OP_over";
67     case 0x15: return "DW_OP_pick";
68     case 0x16: return "DW_OP_swap";
69     case 0x17: return "DW_OP_rot";
70     case 0x18: return "DW_OP_xderef";
71     case 0x19: return "DW_OP_abs";
72     case 0x1a: return "DW_OP_and";
73     case 0x1b: return "DW_OP_div";
74     case 0x1c: return "DW_OP_minus";
75     case 0x1d: return "DW_OP_mod";
76     case 0x1e: return "DW_OP_mul";
77     case 0x1f: return "DW_OP_neg";
78     case 0x20: return "DW_OP_not";
79     case 0x21: return "DW_OP_or";
80     case 0x22: return "DW_OP_plus";
81     case 0x23: return "DW_OP_plus_uconst";
82     case 0x24: return "DW_OP_shl";
83     case 0x25: return "DW_OP_shr";
84     case 0x26: return "DW_OP_shra";
85     case 0x27: return "DW_OP_xor";
86     case 0x2f: return "DW_OP_skip";
87     case 0x28: return "DW_OP_bra";
88     case 0x29: return "DW_OP_eq";
89     case 0x2a: return "DW_OP_ge";
90     case 0x2b: return "DW_OP_gt";
91     case 0x2c: return "DW_OP_le";
92     case 0x2d: return "DW_OP_lt";
93     case 0x2e: return "DW_OP_ne";
94     case 0x30: return "DW_OP_lit0";
95     case 0x31: return "DW_OP_lit1";
96     case 0x32: return "DW_OP_lit2";
97     case 0x33: return "DW_OP_lit3";
98     case 0x34: return "DW_OP_lit4";
99     case 0x35: return "DW_OP_lit5";
100     case 0x36: return "DW_OP_lit6";
101     case 0x37: return "DW_OP_lit7";
102     case 0x38: return "DW_OP_lit8";
103     case 0x39: return "DW_OP_lit9";
104     case 0x3a: return "DW_OP_lit10";
105     case 0x3b: return "DW_OP_lit11";
106     case 0x3c: return "DW_OP_lit12";
107     case 0x3d: return "DW_OP_lit13";
108     case 0x3e: return "DW_OP_lit14";
109     case 0x3f: return "DW_OP_lit15";
110     case 0x40: return "DW_OP_lit16";
111     case 0x41: return "DW_OP_lit17";
112     case 0x42: return "DW_OP_lit18";
113     case 0x43: return "DW_OP_lit19";
114     case 0x44: return "DW_OP_lit20";
115     case 0x45: return "DW_OP_lit21";
116     case 0x46: return "DW_OP_lit22";
117     case 0x47: return "DW_OP_lit23";
118     case 0x48: return "DW_OP_lit24";
119     case 0x49: return "DW_OP_lit25";
120     case 0x4a: return "DW_OP_lit26";
121     case 0x4b: return "DW_OP_lit27";
122     case 0x4c: return "DW_OP_lit28";
123     case 0x4d: return "DW_OP_lit29";
124     case 0x4e: return "DW_OP_lit30";
125     case 0x4f: return "DW_OP_lit31";
126     case 0x50: return "DW_OP_reg0";
127     case 0x51: return "DW_OP_reg1";
128     case 0x52: return "DW_OP_reg2";
129     case 0x53: return "DW_OP_reg3";
130     case 0x54: return "DW_OP_reg4";
131     case 0x55: return "DW_OP_reg5";
132     case 0x56: return "DW_OP_reg6";
133     case 0x57: return "DW_OP_reg7";
134     case 0x58: return "DW_OP_reg8";
135     case 0x59: return "DW_OP_reg9";
136     case 0x5a: return "DW_OP_reg10";
137     case 0x5b: return "DW_OP_reg11";
138     case 0x5c: return "DW_OP_reg12";
139     case 0x5d: return "DW_OP_reg13";
140     case 0x5e: return "DW_OP_reg14";
141     case 0x5f: return "DW_OP_reg15";
142     case 0x60: return "DW_OP_reg16";
143     case 0x61: return "DW_OP_reg17";
144     case 0x62: return "DW_OP_reg18";
145     case 0x63: return "DW_OP_reg19";
146     case 0x64: return "DW_OP_reg20";
147     case 0x65: return "DW_OP_reg21";
148     case 0x66: return "DW_OP_reg22";
149     case 0x67: return "DW_OP_reg23";
150     case 0x68: return "DW_OP_reg24";
151     case 0x69: return "DW_OP_reg25";
152     case 0x6a: return "DW_OP_reg26";
153     case 0x6b: return "DW_OP_reg27";
154     case 0x6c: return "DW_OP_reg28";
155     case 0x6d: return "DW_OP_reg29";
156     case 0x6e: return "DW_OP_reg30";
157     case 0x6f: return "DW_OP_reg31";
158     case 0x70: return "DW_OP_breg0";
159     case 0x71: return "DW_OP_breg1";
160     case 0x72: return "DW_OP_breg2";
161     case 0x73: return "DW_OP_breg3";
162     case 0x74: return "DW_OP_breg4";
163     case 0x75: return "DW_OP_breg5";
164     case 0x76: return "DW_OP_breg6";
165     case 0x77: return "DW_OP_breg7";
166     case 0x78: return "DW_OP_breg8";
167     case 0x79: return "DW_OP_breg9";
168     case 0x7a: return "DW_OP_breg10";
169     case 0x7b: return "DW_OP_breg11";
170     case 0x7c: return "DW_OP_breg12";
171     case 0x7d: return "DW_OP_breg13";
172     case 0x7e: return "DW_OP_breg14";
173     case 0x7f: return "DW_OP_breg15";
174     case 0x80: return "DW_OP_breg16";
175     case 0x81: return "DW_OP_breg17";
176     case 0x82: return "DW_OP_breg18";
177     case 0x83: return "DW_OP_breg19";
178     case 0x84: return "DW_OP_breg20";
179     case 0x85: return "DW_OP_breg21";
180     case 0x86: return "DW_OP_breg22";
181     case 0x87: return "DW_OP_breg23";
182     case 0x88: return "DW_OP_breg24";
183     case 0x89: return "DW_OP_breg25";
184     case 0x8a: return "DW_OP_breg26";
185     case 0x8b: return "DW_OP_breg27";
186     case 0x8c: return "DW_OP_breg28";
187     case 0x8d: return "DW_OP_breg29";
188     case 0x8e: return "DW_OP_breg30";
189     case 0x8f: return "DW_OP_breg31";
190     case 0x90: return "DW_OP_regx";
191     case 0x91: return "DW_OP_fbreg";
192     case 0x92: return "DW_OP_bregx";
193     case 0x93: return "DW_OP_piece";
194     case 0x94: return "DW_OP_deref_size";
195     case 0x95: return "DW_OP_xderef_size";
196     case 0x96: return "DW_OP_nop";
197     case 0x97: return "DW_OP_push_object_address";
198     case 0x98: return "DW_OP_call2";
199     case 0x99: return "DW_OP_call4";
200     case 0x9a: return "DW_OP_call_ref";
201 //    case DW_OP_APPLE_array_ref: return "DW_OP_APPLE_array_ref";
202 //    case DW_OP_APPLE_extern: return "DW_OP_APPLE_extern";
203     case DW_OP_APPLE_uninit: return "DW_OP_APPLE_uninit";
204 //    case DW_OP_APPLE_assign: return "DW_OP_APPLE_assign";
205 //    case DW_OP_APPLE_address_of: return "DW_OP_APPLE_address_of";
206 //    case DW_OP_APPLE_value_of: return "DW_OP_APPLE_value_of";
207 //    case DW_OP_APPLE_deref_type: return "DW_OP_APPLE_deref_type";
208 //    case DW_OP_APPLE_expr_local: return "DW_OP_APPLE_expr_local";
209 //    case DW_OP_APPLE_constf: return "DW_OP_APPLE_constf";
210 //    case DW_OP_APPLE_scalar_cast: return "DW_OP_APPLE_scalar_cast";
211 //    case DW_OP_APPLE_clang_cast: return "DW_OP_APPLE_clang_cast";
212 //    case DW_OP_APPLE_clear: return "DW_OP_APPLE_clear";
213 //    case DW_OP_APPLE_error: return "DW_OP_APPLE_error";
214     default:
215        snprintf (invalid, sizeof(invalid), "Unknown DW_OP constant: 0x%x", val);
216        return invalid;
217   }
218 }
219 
220 
221 //----------------------------------------------------------------------
222 // DWARFExpression constructor
223 //----------------------------------------------------------------------
224 DWARFExpression::DWARFExpression() :
225     m_module_wp(),
226     m_data(),
227     m_reg_kind (eRegisterKindDWARF),
228     m_loclist_slide (LLDB_INVALID_ADDRESS)
229 {
230 }
231 
232 DWARFExpression::DWARFExpression(const DWARFExpression& rhs) :
233     m_module_wp(rhs.m_module_wp),
234     m_data(rhs.m_data),
235     m_reg_kind (rhs.m_reg_kind),
236     m_loclist_slide(rhs.m_loclist_slide)
237 {
238 }
239 
240 
241 DWARFExpression::DWARFExpression(lldb::ModuleSP module_sp, const DataExtractor& data, lldb::offset_t data_offset, lldb::offset_t data_length) :
242     m_module_wp(),
243     m_data(data, data_offset, data_length),
244     m_reg_kind (eRegisterKindDWARF),
245     m_loclist_slide(LLDB_INVALID_ADDRESS)
246 {
247     if (module_sp)
248         m_module_wp = module_sp;
249 }
250 
251 //----------------------------------------------------------------------
252 // Destructor
253 //----------------------------------------------------------------------
254 DWARFExpression::~DWARFExpression()
255 {
256 }
257 
258 
259 bool
260 DWARFExpression::IsValid() const
261 {
262     return m_data.GetByteSize() > 0;
263 }
264 
265 void
266 DWARFExpression::SetOpcodeData (const DataExtractor& data)
267 {
268     m_data = data;
269 }
270 
271 void
272 DWARFExpression::CopyOpcodeData (lldb::ModuleSP module_sp, const DataExtractor& data, lldb::offset_t data_offset, lldb::offset_t data_length)
273 {
274     const uint8_t *bytes = data.PeekData(data_offset, data_length);
275     if (bytes)
276     {
277         m_module_wp = module_sp;
278         m_data.SetData(DataBufferSP(new DataBufferHeap(bytes, data_length)));
279         m_data.SetByteOrder(data.GetByteOrder());
280         m_data.SetAddressByteSize(data.GetAddressByteSize());
281     }
282 }
283 
284 void
285 DWARFExpression::SetOpcodeData (lldb::ModuleSP module_sp, const DataExtractor& data, lldb::offset_t data_offset, lldb::offset_t data_length)
286 {
287     m_module_wp = module_sp;
288     m_data.SetData(data, data_offset, data_length);
289 }
290 
291 void
292 DWARFExpression::DumpLocation (Stream *s, lldb::offset_t offset, lldb::offset_t length, lldb::DescriptionLevel level, ABI *abi) const
293 {
294     if (!m_data.ValidOffsetForDataOfSize(offset, length))
295         return;
296     const lldb::offset_t start_offset = offset;
297     const lldb::offset_t end_offset = offset + length;
298     while (m_data.ValidOffset(offset) && offset < end_offset)
299     {
300         const lldb::offset_t op_offset = offset;
301         const uint8_t op = m_data.GetU8(&offset);
302 
303         switch (level)
304         {
305         default:
306             break;
307 
308         case lldb::eDescriptionLevelBrief:
309             if (offset > start_offset)
310                 s->PutChar(' ');
311             break;
312 
313         case lldb::eDescriptionLevelFull:
314         case lldb::eDescriptionLevelVerbose:
315             if (offset > start_offset)
316                 s->EOL();
317             s->Indent();
318             if (level == lldb::eDescriptionLevelFull)
319                 break;
320             // Fall through for verbose and print offset and DW_OP prefix..
321             s->Printf("0x%8.8" PRIx64 ": %s", op_offset, op >= DW_OP_APPLE_uninit ? "DW_OP_APPLE_" : "DW_OP_");
322             break;
323         }
324 
325         switch (op)
326         {
327         case DW_OP_addr:    *s << "DW_OP_addr(" << m_data.GetAddress(&offset) << ") "; break;         // 0x03 1 address
328         case DW_OP_deref:   *s << "DW_OP_deref"; break;                                               // 0x06
329         case DW_OP_const1u: s->Printf("DW_OP_const1u(0x%2.2x) ", m_data.GetU8(&offset)); break;       // 0x08 1 1-byte constant
330         case DW_OP_const1s: s->Printf("DW_OP_const1s(0x%2.2x) ", m_data.GetU8(&offset)); break;       // 0x09 1 1-byte constant
331         case DW_OP_const2u: s->Printf("DW_OP_const2u(0x%4.4x) ", m_data.GetU16(&offset)); break;      // 0x0a 1 2-byte constant
332         case DW_OP_const2s: s->Printf("DW_OP_const2s(0x%4.4x) ", m_data.GetU16(&offset)); break;      // 0x0b 1 2-byte constant
333         case DW_OP_const4u: s->Printf("DW_OP_const4u(0x%8.8x) ", m_data.GetU32(&offset)); break;      // 0x0c 1 4-byte constant
334         case DW_OP_const4s: s->Printf("DW_OP_const4s(0x%8.8x) ", m_data.GetU32(&offset)); break;      // 0x0d 1 4-byte constant
335         case DW_OP_const8u: s->Printf("DW_OP_const8u(0x%16.16" PRIx64 ") ", m_data.GetU64(&offset)); break;  // 0x0e 1 8-byte constant
336         case DW_OP_const8s: s->Printf("DW_OP_const8s(0x%16.16" PRIx64 ") ", m_data.GetU64(&offset)); break;  // 0x0f 1 8-byte constant
337         case DW_OP_constu:  s->Printf("DW_OP_constu(0x%" PRIx64 ") ", m_data.GetULEB128(&offset)); break;    // 0x10 1 ULEB128 constant
338         case DW_OP_consts:  s->Printf("DW_OP_consts(0x%" PRId64 ") ", m_data.GetSLEB128(&offset)); break;    // 0x11 1 SLEB128 constant
339         case DW_OP_dup:     s->PutCString("DW_OP_dup"); break;                                        // 0x12
340         case DW_OP_drop:    s->PutCString("DW_OP_drop"); break;                                       // 0x13
341         case DW_OP_over:    s->PutCString("DW_OP_over"); break;                                       // 0x14
342         case DW_OP_pick:    s->Printf("DW_OP_pick(0x%2.2x) ", m_data.GetU8(&offset)); break;          // 0x15 1 1-byte stack index
343         case DW_OP_swap:    s->PutCString("DW_OP_swap"); break;                                       // 0x16
344         case DW_OP_rot:     s->PutCString("DW_OP_rot"); break;                                        // 0x17
345         case DW_OP_xderef:  s->PutCString("DW_OP_xderef"); break;                                     // 0x18
346         case DW_OP_abs:     s->PutCString("DW_OP_abs"); break;                                        // 0x19
347         case DW_OP_and:     s->PutCString("DW_OP_and"); break;                                        // 0x1a
348         case DW_OP_div:     s->PutCString("DW_OP_div"); break;                                        // 0x1b
349         case DW_OP_minus:   s->PutCString("DW_OP_minus"); break;                                      // 0x1c
350         case DW_OP_mod:     s->PutCString("DW_OP_mod"); break;                                        // 0x1d
351         case DW_OP_mul:     s->PutCString("DW_OP_mul"); break;                                        // 0x1e
352         case DW_OP_neg:     s->PutCString("DW_OP_neg"); break;                                        // 0x1f
353         case DW_OP_not:     s->PutCString("DW_OP_not"); break;                                        // 0x20
354         case DW_OP_or:      s->PutCString("DW_OP_or"); break;                                         // 0x21
355         case DW_OP_plus:    s->PutCString("DW_OP_plus"); break;                                       // 0x22
356         case DW_OP_plus_uconst:                                                                 // 0x23 1 ULEB128 addend
357             s->Printf("DW_OP_plus_uconst(0x%" PRIx64 ") ", m_data.GetULEB128(&offset));
358             break;
359 
360         case DW_OP_shl:     s->PutCString("DW_OP_shl"); break;                                        // 0x24
361         case DW_OP_shr:     s->PutCString("DW_OP_shr"); break;                                        // 0x25
362         case DW_OP_shra:    s->PutCString("DW_OP_shra"); break;                                       // 0x26
363         case DW_OP_xor:     s->PutCString("DW_OP_xor"); break;                                        // 0x27
364         case DW_OP_skip:    s->Printf("DW_OP_skip(0x%4.4x)", m_data.GetU16(&offset)); break;          // 0x2f 1 signed 2-byte constant
365         case DW_OP_bra:     s->Printf("DW_OP_bra(0x%4.4x)", m_data.GetU16(&offset)); break;           // 0x28 1 signed 2-byte constant
366         case DW_OP_eq:      s->PutCString("DW_OP_eq"); break;                                         // 0x29
367         case DW_OP_ge:      s->PutCString("DW_OP_ge"); break;                                         // 0x2a
368         case DW_OP_gt:      s->PutCString("DW_OP_gt"); break;                                         // 0x2b
369         case DW_OP_le:      s->PutCString("DW_OP_le"); break;                                         // 0x2c
370         case DW_OP_lt:      s->PutCString("DW_OP_lt"); break;                                         // 0x2d
371         case DW_OP_ne:      s->PutCString("DW_OP_ne"); break;                                         // 0x2e
372 
373         case DW_OP_lit0:    // 0x30
374         case DW_OP_lit1:    // 0x31
375         case DW_OP_lit2:    // 0x32
376         case DW_OP_lit3:    // 0x33
377         case DW_OP_lit4:    // 0x34
378         case DW_OP_lit5:    // 0x35
379         case DW_OP_lit6:    // 0x36
380         case DW_OP_lit7:    // 0x37
381         case DW_OP_lit8:    // 0x38
382         case DW_OP_lit9:    // 0x39
383         case DW_OP_lit10:   // 0x3A
384         case DW_OP_lit11:   // 0x3B
385         case DW_OP_lit12:   // 0x3C
386         case DW_OP_lit13:   // 0x3D
387         case DW_OP_lit14:   // 0x3E
388         case DW_OP_lit15:   // 0x3F
389         case DW_OP_lit16:   // 0x40
390         case DW_OP_lit17:   // 0x41
391         case DW_OP_lit18:   // 0x42
392         case DW_OP_lit19:   // 0x43
393         case DW_OP_lit20:   // 0x44
394         case DW_OP_lit21:   // 0x45
395         case DW_OP_lit22:   // 0x46
396         case DW_OP_lit23:   // 0x47
397         case DW_OP_lit24:   // 0x48
398         case DW_OP_lit25:   // 0x49
399         case DW_OP_lit26:   // 0x4A
400         case DW_OP_lit27:   // 0x4B
401         case DW_OP_lit28:   // 0x4C
402         case DW_OP_lit29:   // 0x4D
403         case DW_OP_lit30:   // 0x4E
404         case DW_OP_lit31:   s->Printf("DW_OP_lit%i", op - DW_OP_lit0); break; // 0x4f
405 
406         case DW_OP_reg0:    // 0x50
407         case DW_OP_reg1:    // 0x51
408         case DW_OP_reg2:    // 0x52
409         case DW_OP_reg3:    // 0x53
410         case DW_OP_reg4:    // 0x54
411         case DW_OP_reg5:    // 0x55
412         case DW_OP_reg6:    // 0x56
413         case DW_OP_reg7:    // 0x57
414         case DW_OP_reg8:    // 0x58
415         case DW_OP_reg9:    // 0x59
416         case DW_OP_reg10:   // 0x5A
417         case DW_OP_reg11:   // 0x5B
418         case DW_OP_reg12:   // 0x5C
419         case DW_OP_reg13:   // 0x5D
420         case DW_OP_reg14:   // 0x5E
421         case DW_OP_reg15:   // 0x5F
422         case DW_OP_reg16:   // 0x60
423         case DW_OP_reg17:   // 0x61
424         case DW_OP_reg18:   // 0x62
425         case DW_OP_reg19:   // 0x63
426         case DW_OP_reg20:   // 0x64
427         case DW_OP_reg21:   // 0x65
428         case DW_OP_reg22:   // 0x66
429         case DW_OP_reg23:   // 0x67
430         case DW_OP_reg24:   // 0x68
431         case DW_OP_reg25:   // 0x69
432         case DW_OP_reg26:   // 0x6A
433         case DW_OP_reg27:   // 0x6B
434         case DW_OP_reg28:   // 0x6C
435         case DW_OP_reg29:   // 0x6D
436         case DW_OP_reg30:   // 0x6E
437         case DW_OP_reg31:   // 0x6F
438             {
439                 uint32_t reg_num = op - DW_OP_reg0;
440                 if (abi)
441                 {
442                     RegisterInfo reg_info;
443                     if (abi->GetRegisterInfoByKind(m_reg_kind, reg_num, reg_info))
444                     {
445                         if (reg_info.name)
446                         {
447                             s->PutCString (reg_info.name);
448                             break;
449                         }
450                         else if (reg_info.alt_name)
451                         {
452                             s->PutCString (reg_info.alt_name);
453                             break;
454                         }
455                     }
456                 }
457                 s->Printf("DW_OP_reg%u", reg_num); break;
458             }
459             break;
460 
461         case DW_OP_breg0:
462         case DW_OP_breg1:
463         case DW_OP_breg2:
464         case DW_OP_breg3:
465         case DW_OP_breg4:
466         case DW_OP_breg5:
467         case DW_OP_breg6:
468         case DW_OP_breg7:
469         case DW_OP_breg8:
470         case DW_OP_breg9:
471         case DW_OP_breg10:
472         case DW_OP_breg11:
473         case DW_OP_breg12:
474         case DW_OP_breg13:
475         case DW_OP_breg14:
476         case DW_OP_breg15:
477         case DW_OP_breg16:
478         case DW_OP_breg17:
479         case DW_OP_breg18:
480         case DW_OP_breg19:
481         case DW_OP_breg20:
482         case DW_OP_breg21:
483         case DW_OP_breg22:
484         case DW_OP_breg23:
485         case DW_OP_breg24:
486         case DW_OP_breg25:
487         case DW_OP_breg26:
488         case DW_OP_breg27:
489         case DW_OP_breg28:
490         case DW_OP_breg29:
491         case DW_OP_breg30:
492         case DW_OP_breg31:
493             {
494                 uint32_t reg_num = op - DW_OP_breg0;
495                 int64_t reg_offset = m_data.GetSLEB128(&offset);
496                 if (abi)
497                 {
498                     RegisterInfo reg_info;
499                     if (abi->GetRegisterInfoByKind(m_reg_kind, reg_num, reg_info))
500                     {
501                         if (reg_info.name)
502                         {
503                             s->Printf("[%s%+" PRIi64 "]", reg_info.name, reg_offset);
504                             break;
505                         }
506                         else if (reg_info.alt_name)
507                         {
508                             s->Printf("[%s%+" PRIi64 "]", reg_info.alt_name, reg_offset);
509                             break;
510                         }
511                     }
512                 }
513                 s->Printf("DW_OP_breg%i(0x%" PRIx64 ")", reg_num, reg_offset);
514             }
515             break;
516 
517         case DW_OP_regx:                                                    // 0x90 1 ULEB128 register
518             {
519                 uint32_t reg_num = m_data.GetULEB128(&offset);
520                 if (abi)
521                 {
522                     RegisterInfo reg_info;
523                     if (abi->GetRegisterInfoByKind(m_reg_kind, reg_num, reg_info))
524                     {
525                         if (reg_info.name)
526                         {
527                             s->PutCString (reg_info.name);
528                             break;
529                         }
530                         else if (reg_info.alt_name)
531                         {
532                             s->PutCString (reg_info.alt_name);
533                             break;
534                         }
535                     }
536                 }
537                 s->Printf("DW_OP_regx(%" PRIu32 ")", reg_num); break;
538             }
539             break;
540         case DW_OP_fbreg:                                                   // 0x91 1 SLEB128 offset
541             s->Printf("DW_OP_fbreg(%" PRIi64 ")",m_data.GetSLEB128(&offset));
542             break;
543         case DW_OP_bregx:                                                   // 0x92 2 ULEB128 register followed by SLEB128 offset
544             {
545                 uint32_t reg_num = m_data.GetULEB128(&offset);
546                 int64_t reg_offset = m_data.GetSLEB128(&offset);
547                 if (abi)
548                 {
549                     RegisterInfo reg_info;
550                     if (abi->GetRegisterInfoByKind(m_reg_kind, reg_num, reg_info))
551                     {
552                         if (reg_info.name)
553                         {
554                             s->Printf("[%s%+" PRIi64 "]", reg_info.name, reg_offset);
555                             break;
556                         }
557                         else if (reg_info.alt_name)
558                         {
559                             s->Printf("[%s%+" PRIi64 "]", reg_info.alt_name, reg_offset);
560                             break;
561                         }
562                     }
563                 }
564                 s->Printf("DW_OP_bregx(reg=%" PRIu32 ",offset=%" PRIi64 ")", reg_num, reg_offset);
565             }
566             break;
567         case DW_OP_piece:                                                   // 0x93 1 ULEB128 size of piece addressed
568             s->Printf("DW_OP_piece(0x%" PRIx64 ")", m_data.GetULEB128(&offset));
569             break;
570         case DW_OP_deref_size:                                              // 0x94 1 1-byte size of data retrieved
571             s->Printf("DW_OP_deref_size(0x%2.2x)", m_data.GetU8(&offset));
572             break;
573         case DW_OP_xderef_size:                                             // 0x95 1 1-byte size of data retrieved
574             s->Printf("DW_OP_xderef_size(0x%2.2x)", m_data.GetU8(&offset));
575             break;
576         case DW_OP_nop: s->PutCString("DW_OP_nop"); break;                                    // 0x96
577         case DW_OP_push_object_address: s->PutCString("DW_OP_push_object_address"); break;    // 0x97 DWARF3
578         case DW_OP_call2:                                                   // 0x98 DWARF3 1 2-byte offset of DIE
579             s->Printf("DW_OP_call2(0x%4.4x)", m_data.GetU16(&offset));
580             break;
581         case DW_OP_call4:                                                   // 0x99 DWARF3 1 4-byte offset of DIE
582             s->Printf("DW_OP_call4(0x%8.8x)", m_data.GetU32(&offset));
583             break;
584         case DW_OP_call_ref:                                                // 0x9a DWARF3 1 4- or 8-byte offset of DIE
585             s->Printf("DW_OP_call_ref(0x%8.8" PRIx64 ")", m_data.GetAddress(&offset));
586             break;
587 //      case DW_OP_form_tls_address: s << "form_tls_address"; break;        // 0x9b DWARF3
588 //      case DW_OP_call_frame_cfa: s << "call_frame_cfa"; break;            // 0x9c DWARF3
589 //      case DW_OP_bit_piece:                                               // 0x9d DWARF3 2
590 //          s->Printf("DW_OP_bit_piece(0x%x, 0x%x)", m_data.GetULEB128(&offset), m_data.GetULEB128(&offset));
591 //          break;
592 //      case DW_OP_lo_user:     s->PutCString("DW_OP_lo_user"); break;                        // 0xe0
593 //      case DW_OP_hi_user:     s->PutCString("DW_OP_hi_user"); break;                        // 0xff
594 //        case DW_OP_APPLE_extern:
595 //            s->Printf("DW_OP_APPLE_extern(%" PRIu64 ")", m_data.GetULEB128(&offset));
596 //            break;
597 //        case DW_OP_APPLE_array_ref:
598 //            s->PutCString("DW_OP_APPLE_array_ref");
599 //            break;
600         case DW_OP_GNU_push_tls_address:
601             s->PutCString("DW_OP_GNU_push_tls_address");  // 0xe0
602             break;
603         case DW_OP_APPLE_uninit:
604             s->PutCString("DW_OP_APPLE_uninit");  // 0xF0
605             break;
606 //        case DW_OP_APPLE_assign:        // 0xF1 - pops value off and assigns it to second item on stack (2nd item must have assignable context)
607 //            s->PutCString("DW_OP_APPLE_assign");
608 //            break;
609 //        case DW_OP_APPLE_address_of:    // 0xF2 - gets the address of the top stack item (top item must be a variable, or have value_type that is an address already)
610 //            s->PutCString("DW_OP_APPLE_address_of");
611 //            break;
612 //        case DW_OP_APPLE_value_of:      // 0xF3 - pops the value off the stack and pushes the value of that object (top item must be a variable, or expression local)
613 //            s->PutCString("DW_OP_APPLE_value_of");
614 //            break;
615 //        case DW_OP_APPLE_deref_type:    // 0xF4 - gets the address of the top stack item (top item must be a variable, or a clang type)
616 //            s->PutCString("DW_OP_APPLE_deref_type");
617 //            break;
618 //        case DW_OP_APPLE_expr_local:    // 0xF5 - ULEB128 expression local index
619 //            s->Printf("DW_OP_APPLE_expr_local(%" PRIu64 ")", m_data.GetULEB128(&offset));
620 //            break;
621 //        case DW_OP_APPLE_constf:        // 0xF6 - 1 byte float size, followed by constant float data
622 //            {
623 //                uint8_t float_length = m_data.GetU8(&offset);
624 //                s->Printf("DW_OP_APPLE_constf(<%u> ", float_length);
625 //                m_data.Dump(s, offset, eFormatHex, float_length, 1, UINT32_MAX, DW_INVALID_ADDRESS, 0, 0);
626 //                s->PutChar(')');
627 //                // Consume the float data
628 //                m_data.GetData(&offset, float_length);
629 //            }
630 //            break;
631 //        case DW_OP_APPLE_scalar_cast:
632 //            s->Printf("DW_OP_APPLE_scalar_cast(%s)", Scalar::GetValueTypeAsCString ((Scalar::Type)m_data.GetU8(&offset)));
633 //            break;
634 //        case DW_OP_APPLE_clang_cast:
635 //            {
636 //                clang::Type *clang_type = (clang::Type *)m_data.GetMaxU64(&offset, sizeof(void*));
637 //                s->Printf("DW_OP_APPLE_clang_cast(%p)", clang_type);
638 //            }
639 //            break;
640 //        case DW_OP_APPLE_clear:
641 //            s->PutCString("DW_OP_APPLE_clear");
642 //            break;
643 //        case DW_OP_APPLE_error:         // 0xFF - Stops expression evaluation and returns an error (no args)
644 //            s->PutCString("DW_OP_APPLE_error");
645 //            break;
646         }
647     }
648 }
649 
650 void
651 DWARFExpression::SetLocationListSlide (addr_t slide)
652 {
653     m_loclist_slide = slide;
654 }
655 
656 int
657 DWARFExpression::GetRegisterKind ()
658 {
659     return m_reg_kind;
660 }
661 
662 void
663 DWARFExpression::SetRegisterKind (RegisterKind reg_kind)
664 {
665     m_reg_kind = reg_kind;
666 }
667 
668 bool
669 DWARFExpression::IsLocationList() const
670 {
671     return m_loclist_slide != LLDB_INVALID_ADDRESS;
672 }
673 
674 void
675 DWARFExpression::GetDescription (Stream *s, lldb::DescriptionLevel level, addr_t location_list_base_addr, ABI *abi) const
676 {
677     if (IsLocationList())
678     {
679         // We have a location list
680         lldb::offset_t offset = 0;
681         uint32_t count = 0;
682         addr_t curr_base_addr = location_list_base_addr;
683         while (m_data.ValidOffset(offset))
684         {
685             lldb::addr_t begin_addr_offset = m_data.GetAddress(&offset);
686             lldb::addr_t end_addr_offset = m_data.GetAddress(&offset);
687             if (begin_addr_offset < end_addr_offset)
688             {
689                 if (count > 0)
690                     s->PutCString(", ");
691                 VMRange addr_range(curr_base_addr + begin_addr_offset, curr_base_addr + end_addr_offset);
692                 addr_range.Dump(s, 0, 8);
693                 s->PutChar('{');
694                 lldb::offset_t location_length = m_data.GetU16(&offset);
695                 DumpLocation (s, offset, location_length, level, abi);
696                 s->PutChar('}');
697                 offset += location_length;
698             }
699             else if (begin_addr_offset == 0 && end_addr_offset == 0)
700             {
701                 // The end of the location list is marked by both the start and end offset being zero
702                 break;
703             }
704             else
705             {
706                 if ((m_data.GetAddressByteSize() == 4 && (begin_addr_offset == UINT32_MAX)) ||
707                     (m_data.GetAddressByteSize() == 8 && (begin_addr_offset == UINT64_MAX)))
708                 {
709                     curr_base_addr = end_addr_offset + location_list_base_addr;
710                     // We have a new base address
711                     if (count > 0)
712                         s->PutCString(", ");
713                     *s << "base_addr = " << end_addr_offset;
714                 }
715             }
716 
717             count++;
718         }
719     }
720     else
721     {
722         // We have a normal location that contains DW_OP location opcodes
723         DumpLocation (s, 0, m_data.GetByteSize(), level, abi);
724     }
725 }
726 
727 static bool
728 ReadRegisterValueAsScalar
729 (
730     RegisterContext *reg_ctx,
731     lldb::RegisterKind reg_kind,
732     uint32_t reg_num,
733     Error *error_ptr,
734     Value &value
735 )
736 {
737     if (reg_ctx == NULL)
738     {
739         if (error_ptr)
740             error_ptr->SetErrorStringWithFormat("No register context in frame.\n");
741     }
742     else
743     {
744         uint32_t native_reg = reg_ctx->ConvertRegisterKindToRegisterNumber(reg_kind, reg_num);
745         if (native_reg == LLDB_INVALID_REGNUM)
746         {
747             if (error_ptr)
748                 error_ptr->SetErrorStringWithFormat("Unable to convert register kind=%u reg_num=%u to a native register number.\n", reg_kind, reg_num);
749         }
750         else
751         {
752             const RegisterInfo *reg_info = reg_ctx->GetRegisterInfoAtIndex(native_reg);
753             RegisterValue reg_value;
754             if (reg_ctx->ReadRegister (reg_info, reg_value))
755             {
756                 if (reg_value.GetScalarValue(value.GetScalar()))
757                 {
758                     value.SetValueType (Value::eValueTypeScalar);
759                     value.SetContext (Value::eContextTypeRegisterInfo,
760                                       const_cast<RegisterInfo *>(reg_info));
761                     if (error_ptr)
762                         error_ptr->Clear();
763                     return true;
764                 }
765                 else
766                 {
767                     // If we get this error, then we need to implement a value
768                     // buffer in the dwarf expression evaluation function...
769                     if (error_ptr)
770                         error_ptr->SetErrorStringWithFormat ("register %s can't be converted to a scalar value",
771                                                              reg_info->name);
772                 }
773             }
774             else
775             {
776                 if (error_ptr)
777                     error_ptr->SetErrorStringWithFormat("register %s is not available", reg_info->name);
778             }
779         }
780     }
781     return false;
782 }
783 
784 //bool
785 //DWARFExpression::LocationListContainsLoadAddress (Process* process, const Address &addr) const
786 //{
787 //    return LocationListContainsLoadAddress(process, addr.GetLoadAddress(process));
788 //}
789 //
790 //bool
791 //DWARFExpression::LocationListContainsLoadAddress (Process* process, addr_t load_addr) const
792 //{
793 //    if (load_addr == LLDB_INVALID_ADDRESS)
794 //        return false;
795 //
796 //    if (IsLocationList())
797 //    {
798 //        lldb::offset_t offset = 0;
799 //
800 //        addr_t loc_list_base_addr = m_loclist_slide.GetLoadAddress(process);
801 //
802 //        if (loc_list_base_addr == LLDB_INVALID_ADDRESS)
803 //            return false;
804 //
805 //        while (m_data.ValidOffset(offset))
806 //        {
807 //            // We need to figure out what the value is for the location.
808 //            addr_t lo_pc = m_data.GetAddress(&offset);
809 //            addr_t hi_pc = m_data.GetAddress(&offset);
810 //            if (lo_pc == 0 && hi_pc == 0)
811 //                break;
812 //            else
813 //            {
814 //                lo_pc += loc_list_base_addr;
815 //                hi_pc += loc_list_base_addr;
816 //
817 //                if (lo_pc <= load_addr && load_addr < hi_pc)
818 //                    return true;
819 //
820 //                offset += m_data.GetU16(&offset);
821 //            }
822 //        }
823 //    }
824 //    return false;
825 //}
826 
827 static offset_t
828 GetOpcodeDataSize (const DataExtractor &data, const lldb::offset_t data_offset, const uint8_t op)
829 {
830     lldb::offset_t offset = data_offset;
831     switch (op)
832     {
833         case DW_OP_addr:
834         case DW_OP_call_ref:    // 0x9a 1 address sized offset of DIE (DWARF3)
835             return data.GetAddressByteSize();
836 
837         // Opcodes with no arguments
838         case DW_OP_deref:   // 0x06
839         case DW_OP_dup:     // 0x12
840         case DW_OP_drop:    // 0x13
841         case DW_OP_over:    // 0x14
842         case DW_OP_swap:    // 0x16
843         case DW_OP_rot:     // 0x17
844         case DW_OP_xderef:  // 0x18
845         case DW_OP_abs:     // 0x19
846         case DW_OP_and:     // 0x1a
847         case DW_OP_div:     // 0x1b
848         case DW_OP_minus:   // 0x1c
849         case DW_OP_mod:     // 0x1d
850         case DW_OP_mul:     // 0x1e
851         case DW_OP_neg:     // 0x1f
852         case DW_OP_not:     // 0x20
853         case DW_OP_or:      // 0x21
854         case DW_OP_plus:    // 0x22
855         case DW_OP_shl:     // 0x24
856         case DW_OP_shr:     // 0x25
857         case DW_OP_shra:    // 0x26
858         case DW_OP_xor:     // 0x27
859         case DW_OP_eq:      // 0x29
860         case DW_OP_ge:      // 0x2a
861         case DW_OP_gt:      // 0x2b
862         case DW_OP_le:      // 0x2c
863         case DW_OP_lt:      // 0x2d
864         case DW_OP_ne:      // 0x2e
865         case DW_OP_lit0:    // 0x30
866         case DW_OP_lit1:    // 0x31
867         case DW_OP_lit2:    // 0x32
868         case DW_OP_lit3:    // 0x33
869         case DW_OP_lit4:    // 0x34
870         case DW_OP_lit5:    // 0x35
871         case DW_OP_lit6:    // 0x36
872         case DW_OP_lit7:    // 0x37
873         case DW_OP_lit8:    // 0x38
874         case DW_OP_lit9:    // 0x39
875         case DW_OP_lit10:   // 0x3A
876         case DW_OP_lit11:   // 0x3B
877         case DW_OP_lit12:   // 0x3C
878         case DW_OP_lit13:   // 0x3D
879         case DW_OP_lit14:   // 0x3E
880         case DW_OP_lit15:   // 0x3F
881         case DW_OP_lit16:   // 0x40
882         case DW_OP_lit17:   // 0x41
883         case DW_OP_lit18:   // 0x42
884         case DW_OP_lit19:   // 0x43
885         case DW_OP_lit20:   // 0x44
886         case DW_OP_lit21:   // 0x45
887         case DW_OP_lit22:   // 0x46
888         case DW_OP_lit23:   // 0x47
889         case DW_OP_lit24:   // 0x48
890         case DW_OP_lit25:   // 0x49
891         case DW_OP_lit26:   // 0x4A
892         case DW_OP_lit27:   // 0x4B
893         case DW_OP_lit28:   // 0x4C
894         case DW_OP_lit29:   // 0x4D
895         case DW_OP_lit30:   // 0x4E
896         case DW_OP_lit31:   // 0x4f
897         case DW_OP_reg0:    // 0x50
898         case DW_OP_reg1:    // 0x51
899         case DW_OP_reg2:    // 0x52
900         case DW_OP_reg3:    // 0x53
901         case DW_OP_reg4:    // 0x54
902         case DW_OP_reg5:    // 0x55
903         case DW_OP_reg6:    // 0x56
904         case DW_OP_reg7:    // 0x57
905         case DW_OP_reg8:    // 0x58
906         case DW_OP_reg9:    // 0x59
907         case DW_OP_reg10:   // 0x5A
908         case DW_OP_reg11:   // 0x5B
909         case DW_OP_reg12:   // 0x5C
910         case DW_OP_reg13:   // 0x5D
911         case DW_OP_reg14:   // 0x5E
912         case DW_OP_reg15:   // 0x5F
913         case DW_OP_reg16:   // 0x60
914         case DW_OP_reg17:   // 0x61
915         case DW_OP_reg18:   // 0x62
916         case DW_OP_reg19:   // 0x63
917         case DW_OP_reg20:   // 0x64
918         case DW_OP_reg21:   // 0x65
919         case DW_OP_reg22:   // 0x66
920         case DW_OP_reg23:   // 0x67
921         case DW_OP_reg24:   // 0x68
922         case DW_OP_reg25:   // 0x69
923         case DW_OP_reg26:   // 0x6A
924         case DW_OP_reg27:   // 0x6B
925         case DW_OP_reg28:   // 0x6C
926         case DW_OP_reg29:   // 0x6D
927         case DW_OP_reg30:   // 0x6E
928         case DW_OP_reg31:   // 0x6F
929         case DW_OP_nop:     // 0x96
930         case DW_OP_push_object_address: // 0x97 DWARF3
931         case DW_OP_form_tls_address:    // 0x9b DWARF3
932         case DW_OP_call_frame_cfa:      // 0x9c DWARF3
933         case DW_OP_stack_value: // 0x9f DWARF4
934         case DW_OP_GNU_push_tls_address: // 0xe0 GNU extension
935             return 0;
936 
937         // Opcodes with a single 1 byte arguments
938         case DW_OP_const1u:     // 0x08 1 1-byte constant
939         case DW_OP_const1s:     // 0x09 1 1-byte constant
940         case DW_OP_pick:        // 0x15 1 1-byte stack index
941         case DW_OP_deref_size:  // 0x94 1 1-byte size of data retrieved
942         case DW_OP_xderef_size: // 0x95 1 1-byte size of data retrieved
943             return 1;
944 
945         // Opcodes with a single 2 byte arguments
946         case DW_OP_const2u:     // 0x0a 1 2-byte constant
947         case DW_OP_const2s:     // 0x0b 1 2-byte constant
948         case DW_OP_skip:        // 0x2f 1 signed 2-byte constant
949         case DW_OP_bra:         // 0x28 1 signed 2-byte constant
950         case DW_OP_call2:       // 0x98 1 2-byte offset of DIE (DWARF3)
951             return 2;
952 
953         // Opcodes with a single 4 byte arguments
954         case DW_OP_const4u:     // 0x0c 1 4-byte constant
955         case DW_OP_const4s:     // 0x0d 1 4-byte constant
956         case DW_OP_call4:       // 0x99 1 4-byte offset of DIE (DWARF3)
957             return 4;
958 
959         // Opcodes with a single 8 byte arguments
960         case DW_OP_const8u:     // 0x0e 1 8-byte constant
961         case DW_OP_const8s:     // 0x0f 1 8-byte constant
962              return 8;
963 
964         // All opcodes that have a single ULEB (signed or unsigned) argument
965         case DW_OP_constu:      // 0x10 1 ULEB128 constant
966         case DW_OP_consts:      // 0x11 1 SLEB128 constant
967         case DW_OP_plus_uconst: // 0x23 1 ULEB128 addend
968         case DW_OP_breg0:       // 0x70 1 ULEB128 register
969         case DW_OP_breg1:       // 0x71 1 ULEB128 register
970         case DW_OP_breg2:       // 0x72 1 ULEB128 register
971         case DW_OP_breg3:       // 0x73 1 ULEB128 register
972         case DW_OP_breg4:       // 0x74 1 ULEB128 register
973         case DW_OP_breg5:       // 0x75 1 ULEB128 register
974         case DW_OP_breg6:       // 0x76 1 ULEB128 register
975         case DW_OP_breg7:       // 0x77 1 ULEB128 register
976         case DW_OP_breg8:       // 0x78 1 ULEB128 register
977         case DW_OP_breg9:       // 0x79 1 ULEB128 register
978         case DW_OP_breg10:      // 0x7a 1 ULEB128 register
979         case DW_OP_breg11:      // 0x7b 1 ULEB128 register
980         case DW_OP_breg12:      // 0x7c 1 ULEB128 register
981         case DW_OP_breg13:      // 0x7d 1 ULEB128 register
982         case DW_OP_breg14:      // 0x7e 1 ULEB128 register
983         case DW_OP_breg15:      // 0x7f 1 ULEB128 register
984         case DW_OP_breg16:      // 0x80 1 ULEB128 register
985         case DW_OP_breg17:      // 0x81 1 ULEB128 register
986         case DW_OP_breg18:      // 0x82 1 ULEB128 register
987         case DW_OP_breg19:      // 0x83 1 ULEB128 register
988         case DW_OP_breg20:      // 0x84 1 ULEB128 register
989         case DW_OP_breg21:      // 0x85 1 ULEB128 register
990         case DW_OP_breg22:      // 0x86 1 ULEB128 register
991         case DW_OP_breg23:      // 0x87 1 ULEB128 register
992         case DW_OP_breg24:      // 0x88 1 ULEB128 register
993         case DW_OP_breg25:      // 0x89 1 ULEB128 register
994         case DW_OP_breg26:      // 0x8a 1 ULEB128 register
995         case DW_OP_breg27:      // 0x8b 1 ULEB128 register
996         case DW_OP_breg28:      // 0x8c 1 ULEB128 register
997         case DW_OP_breg29:      // 0x8d 1 ULEB128 register
998         case DW_OP_breg30:      // 0x8e 1 ULEB128 register
999         case DW_OP_breg31:      // 0x8f 1 ULEB128 register
1000         case DW_OP_regx:        // 0x90 1 ULEB128 register
1001         case DW_OP_fbreg:       // 0x91 1 SLEB128 offset
1002         case DW_OP_piece:       // 0x93 1 ULEB128 size of piece addressed
1003             data.Skip_LEB128(&offset);
1004             return offset - data_offset;
1005 
1006             // All opcodes that have a 2 ULEB (signed or unsigned) arguments
1007         case DW_OP_bregx:       // 0x92 2 ULEB128 register followed by SLEB128 offset
1008         case DW_OP_bit_piece:   // 0x9d ULEB128 bit size, ULEB128 bit offset (DWARF3);
1009             data.Skip_LEB128(&offset);
1010             data.Skip_LEB128(&offset);
1011             return offset - data_offset;
1012 
1013         case DW_OP_implicit_value: // 0x9e ULEB128 size followed by block of that size (DWARF4)
1014             {
1015                 uint64_t block_len = data.Skip_LEB128(&offset);
1016                 offset += block_len;
1017                 return offset - data_offset;
1018             }
1019 
1020         default:
1021             break;
1022     }
1023     return LLDB_INVALID_OFFSET;
1024 }
1025 
1026 lldb::addr_t
1027 DWARFExpression::GetLocation_DW_OP_addr (uint32_t op_addr_idx, bool &error) const
1028 {
1029     error = false;
1030     if (IsLocationList())
1031         return LLDB_INVALID_ADDRESS;
1032     lldb::offset_t offset = 0;
1033     uint32_t curr_op_addr_idx = 0;
1034     while (m_data.ValidOffset(offset))
1035     {
1036         const uint8_t op = m_data.GetU8(&offset);
1037 
1038         if (op == DW_OP_addr)
1039         {
1040             const lldb::addr_t op_file_addr = m_data.GetAddress(&offset);
1041             if (curr_op_addr_idx == op_addr_idx)
1042                 return op_file_addr;
1043             else
1044                 ++curr_op_addr_idx;
1045         }
1046         else
1047         {
1048             const offset_t op_arg_size = GetOpcodeDataSize (m_data, offset, op);
1049             if (op_arg_size == LLDB_INVALID_OFFSET)
1050             {
1051                 error = true;
1052                 break;
1053             }
1054             offset += op_arg_size;
1055         }
1056     }
1057     return LLDB_INVALID_ADDRESS;
1058 }
1059 
1060 bool
1061 DWARFExpression::Update_DW_OP_addr (lldb::addr_t file_addr)
1062 {
1063     if (IsLocationList())
1064         return false;
1065     lldb::offset_t offset = 0;
1066     while (m_data.ValidOffset(offset))
1067     {
1068         const uint8_t op = m_data.GetU8(&offset);
1069 
1070         if (op == DW_OP_addr)
1071         {
1072             const uint32_t addr_byte_size = m_data.GetAddressByteSize();
1073             // We have to make a copy of the data as we don't know if this
1074             // data is from a read only memory mapped buffer, so we duplicate
1075             // all of the data first, then modify it, and if all goes well,
1076             // we then replace the data for this expression
1077 
1078             // So first we copy the data into a heap buffer
1079             std::unique_ptr<DataBufferHeap> head_data_ap (new DataBufferHeap (m_data.GetDataStart(),
1080                                                                              m_data.GetByteSize()));
1081 
1082             // Make en encoder so we can write the address into the buffer using
1083             // the correct byte order (endianness)
1084             DataEncoder encoder (head_data_ap->GetBytes(),
1085                                  head_data_ap->GetByteSize(),
1086                                  m_data.GetByteOrder(),
1087                                  addr_byte_size);
1088 
1089             // Replace the address in the new buffer
1090             if (encoder.PutMaxU64 (offset, addr_byte_size, file_addr) == UINT32_MAX)
1091                 return false;
1092 
1093             // All went well, so now we can reset the data using a shared
1094             // pointer to the heap data so "m_data" will now correctly
1095             // manage the heap data.
1096             m_data.SetData (DataBufferSP (head_data_ap.release()));
1097             return true;
1098         }
1099         else
1100         {
1101             const offset_t op_arg_size = GetOpcodeDataSize (m_data, offset, op);
1102             if (op_arg_size == LLDB_INVALID_OFFSET)
1103                 break;
1104             offset += op_arg_size;
1105         }
1106     }
1107     return false;
1108 }
1109 
1110 bool
1111 DWARFExpression::LocationListContainsAddress (lldb::addr_t loclist_base_addr, lldb::addr_t addr) const
1112 {
1113     if (addr == LLDB_INVALID_ADDRESS)
1114         return false;
1115 
1116     if (IsLocationList())
1117     {
1118         lldb::offset_t offset = 0;
1119 
1120         if (loclist_base_addr == LLDB_INVALID_ADDRESS)
1121             return false;
1122 
1123         while (m_data.ValidOffset(offset))
1124         {
1125             // We need to figure out what the value is for the location.
1126             addr_t lo_pc = m_data.GetAddress(&offset);
1127             addr_t hi_pc = m_data.GetAddress(&offset);
1128             if (lo_pc == 0 && hi_pc == 0)
1129                 break;
1130             else
1131             {
1132                 lo_pc += loclist_base_addr - m_loclist_slide;
1133                 hi_pc += loclist_base_addr - m_loclist_slide;
1134 
1135                 if (lo_pc <= addr && addr < hi_pc)
1136                     return true;
1137 
1138                 offset += m_data.GetU16(&offset);
1139             }
1140         }
1141     }
1142     return false;
1143 }
1144 
1145 bool
1146 DWARFExpression::GetLocation (addr_t base_addr, addr_t pc, lldb::offset_t &offset, lldb::offset_t &length)
1147 {
1148     offset = 0;
1149     if (!IsLocationList())
1150     {
1151         length = m_data.GetByteSize();
1152         return true;
1153     }
1154 
1155     if (base_addr != LLDB_INVALID_ADDRESS && pc != LLDB_INVALID_ADDRESS)
1156     {
1157         addr_t curr_base_addr = base_addr;
1158 
1159         while (m_data.ValidOffset(offset))
1160         {
1161             // We need to figure out what the value is for the location.
1162             addr_t lo_pc = m_data.GetAddress(&offset);
1163             addr_t hi_pc = m_data.GetAddress(&offset);
1164             if (lo_pc == 0 && hi_pc == 0)
1165             {
1166                 break;
1167             }
1168             else
1169             {
1170                 lo_pc += curr_base_addr - m_loclist_slide;
1171                 hi_pc += curr_base_addr - m_loclist_slide;
1172 
1173                 length = m_data.GetU16(&offset);
1174 
1175                 if (length > 0 && lo_pc <= pc && pc < hi_pc)
1176                     return true;
1177 
1178                 offset += length;
1179             }
1180         }
1181     }
1182     offset = LLDB_INVALID_OFFSET;
1183     length = 0;
1184     return false;
1185 }
1186 
1187 bool
1188 DWARFExpression::DumpLocationForAddress (Stream *s,
1189                                          lldb::DescriptionLevel level,
1190                                          addr_t base_addr,
1191                                          addr_t address,
1192                                          ABI *abi)
1193 {
1194     lldb::offset_t offset = 0;
1195     lldb::offset_t length = 0;
1196 
1197     if (GetLocation (base_addr, address, offset, length))
1198     {
1199         if (length > 0)
1200         {
1201             DumpLocation(s, offset, length, level, abi);
1202             return true;
1203         }
1204     }
1205     return false;
1206 }
1207 
1208 bool
1209 DWARFExpression::Evaluate
1210 (
1211     ExecutionContextScope *exe_scope,
1212     ClangExpressionVariableList *expr_locals,
1213     ClangExpressionDeclMap *decl_map,
1214     lldb::addr_t loclist_base_load_addr,
1215     const Value* initial_value_ptr,
1216     Value& result,
1217     Error *error_ptr
1218 ) const
1219 {
1220     ExecutionContext exe_ctx (exe_scope);
1221     return Evaluate(&exe_ctx, expr_locals, decl_map, NULL, loclist_base_load_addr, initial_value_ptr, result, error_ptr);
1222 }
1223 
1224 bool
1225 DWARFExpression::Evaluate
1226 (
1227     ExecutionContext *exe_ctx,
1228     ClangExpressionVariableList *expr_locals,
1229     ClangExpressionDeclMap *decl_map,
1230     RegisterContext *reg_ctx,
1231     lldb::addr_t loclist_base_load_addr,
1232     const Value* initial_value_ptr,
1233     Value& result,
1234     Error *error_ptr
1235 ) const
1236 {
1237     ModuleSP module_sp = m_module_wp.lock();
1238 
1239     if (IsLocationList())
1240     {
1241         lldb::offset_t offset = 0;
1242         addr_t pc;
1243         StackFrame *frame = NULL;
1244         if (reg_ctx)
1245             pc = reg_ctx->GetPC();
1246         else
1247         {
1248             frame = exe_ctx->GetFramePtr();
1249             if (!frame)
1250                 return false;
1251             RegisterContextSP reg_ctx_sp = frame->GetRegisterContext();
1252             if (!reg_ctx_sp)
1253                 return false;
1254             pc = reg_ctx_sp->GetPC();
1255         }
1256 
1257         if (loclist_base_load_addr != LLDB_INVALID_ADDRESS)
1258         {
1259             if (pc == LLDB_INVALID_ADDRESS)
1260             {
1261                 if (error_ptr)
1262                     error_ptr->SetErrorString("Invalid PC in frame.");
1263                 return false;
1264             }
1265 
1266             addr_t curr_loclist_base_load_addr = loclist_base_load_addr;
1267 
1268             while (m_data.ValidOffset(offset))
1269             {
1270                 // We need to figure out what the value is for the location.
1271                 addr_t lo_pc = m_data.GetAddress(&offset);
1272                 addr_t hi_pc = m_data.GetAddress(&offset);
1273                 if (lo_pc == 0 && hi_pc == 0)
1274                 {
1275                     break;
1276                 }
1277                 else
1278                 {
1279                     lo_pc += curr_loclist_base_load_addr - m_loclist_slide;
1280                     hi_pc += curr_loclist_base_load_addr - m_loclist_slide;
1281 
1282                     uint16_t length = m_data.GetU16(&offset);
1283 
1284                     if (length > 0 && lo_pc <= pc && pc < hi_pc)
1285                     {
1286                         return DWARFExpression::Evaluate (exe_ctx, expr_locals, decl_map, reg_ctx, module_sp, m_data, offset, length, m_reg_kind, initial_value_ptr, result, error_ptr);
1287                     }
1288                     offset += length;
1289                 }
1290             }
1291         }
1292         if (error_ptr)
1293             error_ptr->SetErrorString ("variable not available");
1294         return false;
1295     }
1296 
1297     // Not a location list, just a single expression.
1298     return DWARFExpression::Evaluate (exe_ctx, expr_locals, decl_map, reg_ctx, module_sp, m_data, 0, m_data.GetByteSize(), m_reg_kind, initial_value_ptr, result, error_ptr);
1299 }
1300 
1301 
1302 
1303 bool
1304 DWARFExpression::Evaluate
1305 (
1306     ExecutionContext *exe_ctx,
1307     ClangExpressionVariableList *expr_locals,
1308     ClangExpressionDeclMap *decl_map,
1309     RegisterContext *reg_ctx,
1310     lldb::ModuleSP opcode_ctx,
1311     const DataExtractor& opcodes,
1312     const lldb::offset_t opcodes_offset,
1313     const lldb::offset_t opcodes_length,
1314     const lldb::RegisterKind reg_kind,
1315     const Value* initial_value_ptr,
1316     Value& result,
1317     Error *error_ptr
1318 )
1319 {
1320 
1321     if (opcodes_length == 0)
1322     {
1323         if (error_ptr)
1324             error_ptr->SetErrorString ("no location, value may have been optimized out");
1325         return false;
1326     }
1327     std::vector<Value> stack;
1328 
1329     Process *process = NULL;
1330     StackFrame *frame = NULL;
1331 
1332     if (exe_ctx)
1333     {
1334         process = exe_ctx->GetProcessPtr();
1335         frame = exe_ctx->GetFramePtr();
1336     }
1337     if (reg_ctx == NULL && frame)
1338         reg_ctx = frame->GetRegisterContext().get();
1339 
1340     if (initial_value_ptr)
1341         stack.push_back(*initial_value_ptr);
1342 
1343     lldb::offset_t offset = opcodes_offset;
1344     const lldb::offset_t end_offset = opcodes_offset + opcodes_length;
1345     Value tmp;
1346     uint32_t reg_num;
1347 
1348     /// Insertion point for evaluating multi-piece expression.
1349     uint64_t op_piece_offset = 0;
1350     Value pieces; // Used for DW_OP_piece
1351 
1352     // Make sure all of the data is available in opcodes.
1353     if (!opcodes.ValidOffsetForDataOfSize(opcodes_offset, opcodes_length))
1354     {
1355         if (error_ptr)
1356             error_ptr->SetErrorString ("invalid offset and/or length for opcodes buffer.");
1357         return false;
1358     }
1359     Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
1360 
1361 
1362     while (opcodes.ValidOffset(offset) && offset < end_offset)
1363     {
1364         const lldb::offset_t op_offset = offset;
1365         const uint8_t op = opcodes.GetU8(&offset);
1366 
1367         if (log && log->GetVerbose())
1368         {
1369             size_t count = stack.size();
1370             log->Printf("Stack before operation has %" PRIu64 " values:", (uint64_t)count);
1371             for (size_t i=0; i<count; ++i)
1372             {
1373                 StreamString new_value;
1374                 new_value.Printf("[%" PRIu64 "]", (uint64_t)i);
1375                 stack[i].Dump(&new_value);
1376                 log->Printf("  %s", new_value.GetData());
1377             }
1378             log->Printf("0x%8.8" PRIx64 ": %s", op_offset, DW_OP_value_to_name(op));
1379         }
1380         switch (op)
1381         {
1382         //----------------------------------------------------------------------
1383         // The DW_OP_addr operation has a single operand that encodes a machine
1384         // address and whose size is the size of an address on the target machine.
1385         //----------------------------------------------------------------------
1386         case DW_OP_addr:
1387             stack.push_back(Scalar(opcodes.GetAddress(&offset)));
1388             stack.back().SetValueType (Value::eValueTypeFileAddress);
1389             break;
1390 
1391         //----------------------------------------------------------------------
1392         // The DW_OP_addr_sect_offset4 is used for any location expressions in
1393         // shared libraries that have a location like:
1394         //  DW_OP_addr(0x1000)
1395         // If this address resides in a shared library, then this virtual
1396         // address won't make sense when it is evaluated in the context of a
1397         // running process where shared libraries have been slid. To account for
1398         // this, this new address type where we can store the section pointer
1399         // and a 4 byte offset.
1400         //----------------------------------------------------------------------
1401 //      case DW_OP_addr_sect_offset4:
1402 //          {
1403 //              result_type = eResultTypeFileAddress;
1404 //              lldb::Section *sect = (lldb::Section *)opcodes.GetMaxU64(&offset, sizeof(void *));
1405 //              lldb::addr_t sect_offset = opcodes.GetU32(&offset);
1406 //
1407 //              Address so_addr (sect, sect_offset);
1408 //              lldb::addr_t load_addr = so_addr.GetLoadAddress();
1409 //              if (load_addr != LLDB_INVALID_ADDRESS)
1410 //              {
1411 //                  // We successfully resolve a file address to a load
1412 //                  // address.
1413 //                  stack.push_back(load_addr);
1414 //                  break;
1415 //              }
1416 //              else
1417 //              {
1418 //                  // We were able
1419 //                  if (error_ptr)
1420 //                      error_ptr->SetErrorStringWithFormat ("Section %s in %s is not currently loaded.\n", sect->GetName().AsCString(), sect->GetModule()->GetFileSpec().GetFilename().AsCString());
1421 //                  return false;
1422 //              }
1423 //          }
1424 //          break;
1425 
1426         //----------------------------------------------------------------------
1427         // OPCODE: DW_OP_deref
1428         // OPERANDS: none
1429         // DESCRIPTION: Pops the top stack entry and treats it as an address.
1430         // The value retrieved from that address is pushed. The size of the
1431         // data retrieved from the dereferenced address is the size of an
1432         // address on the target machine.
1433         //----------------------------------------------------------------------
1434         case DW_OP_deref:
1435             {
1436                 if (stack.empty())
1437                 {
1438                     if (error_ptr)
1439                         error_ptr->SetErrorString("Expression stack empty for DW_OP_deref.");
1440                     return false;
1441                 }
1442                 Value::ValueType value_type = stack.back().GetValueType();
1443                 switch (value_type)
1444                 {
1445                 case Value::eValueTypeHostAddress:
1446                     {
1447                         void *src = (void *)stack.back().GetScalar().ULongLong();
1448                         intptr_t ptr;
1449                         ::memcpy (&ptr, src, sizeof(void *));
1450                         stack.back().GetScalar() = ptr;
1451                         stack.back().ClearContext();
1452                     }
1453                     break;
1454                 case Value::eValueTypeLoadAddress:
1455                     if (exe_ctx)
1456                     {
1457                         if (process)
1458                         {
1459                             lldb::addr_t pointer_addr = stack.back().GetScalar().ULongLong(LLDB_INVALID_ADDRESS);
1460                             Error error;
1461                             lldb::addr_t pointer_value = process->ReadPointerFromMemory(pointer_addr, error);
1462                             if (pointer_value != LLDB_INVALID_ADDRESS)
1463                             {
1464                                 stack.back().GetScalar() = pointer_value;
1465                                 stack.back().ClearContext();
1466                             }
1467                             else
1468                             {
1469                                 if (error_ptr)
1470                                     error_ptr->SetErrorStringWithFormat ("Failed to dereference pointer from 0x%" PRIx64 " for DW_OP_deref: %s\n",
1471                                                                          pointer_addr,
1472                                                                          error.AsCString());
1473                                 return false;
1474                             }
1475                         }
1476                         else
1477                         {
1478                             if (error_ptr)
1479                                 error_ptr->SetErrorStringWithFormat ("NULL process for DW_OP_deref.\n");
1480                             return false;
1481                         }
1482                     }
1483                     else
1484                     {
1485                         if (error_ptr)
1486                             error_ptr->SetErrorStringWithFormat ("NULL execution context for DW_OP_deref.\n");
1487                         return false;
1488                     }
1489                     break;
1490 
1491                 default:
1492                     break;
1493                 }
1494 
1495             }
1496             break;
1497 
1498         //----------------------------------------------------------------------
1499         // OPCODE: DW_OP_deref_size
1500         // OPERANDS: 1
1501         //  1 - uint8_t that specifies the size of the data to dereference.
1502         // DESCRIPTION: Behaves like the DW_OP_deref operation: it pops the top
1503         // stack entry and treats it as an address. The value retrieved from that
1504         // address is pushed. In the DW_OP_deref_size operation, however, the
1505         // size in bytes of the data retrieved from the dereferenced address is
1506         // specified by the single operand. This operand is a 1-byte unsigned
1507         // integral constant whose value may not be larger than the size of an
1508         // address on the target machine. The data retrieved is zero extended
1509         // to the size of an address on the target machine before being pushed
1510         // on the expression stack.
1511         //----------------------------------------------------------------------
1512         case DW_OP_deref_size:
1513             {
1514                 if (stack.empty())
1515                 {
1516                     if (error_ptr)
1517                         error_ptr->SetErrorString("Expression stack empty for DW_OP_deref_size.");
1518                     return false;
1519                 }
1520                 uint8_t size = opcodes.GetU8(&offset);
1521                 Value::ValueType value_type = stack.back().GetValueType();
1522                 switch (value_type)
1523                 {
1524                 case Value::eValueTypeHostAddress:
1525                     {
1526                         void *src = (void *)stack.back().GetScalar().ULongLong();
1527                         intptr_t ptr;
1528                         ::memcpy (&ptr, src, sizeof(void *));
1529                         // I can't decide whether the size operand should apply to the bytes in their
1530                         // lldb-host endianness or the target endianness.. I doubt this'll ever come up
1531                         // but I'll opt for assuming big endian regardless.
1532                         switch (size)
1533                         {
1534                             case 1: ptr = ptr & 0xff; break;
1535                             case 2: ptr = ptr & 0xffff; break;
1536                             case 3: ptr = ptr & 0xffffff; break;
1537                             case 4: ptr = ptr & 0xffffffff; break;
1538                             // the casts are added to work around the case where intptr_t is a 32 bit quantity;
1539                             // presumably we won't hit the 5..7 cases if (void*) is 32-bits in this program.
1540                             case 5: ptr = (intptr_t) ptr & 0xffffffffffULL; break;
1541                             case 6: ptr = (intptr_t) ptr & 0xffffffffffffULL; break;
1542                             case 7: ptr = (intptr_t) ptr & 0xffffffffffffffULL; break;
1543                             default: break;
1544                         }
1545                         stack.back().GetScalar() = ptr;
1546                         stack.back().ClearContext();
1547                     }
1548                     break;
1549                 case Value::eValueTypeLoadAddress:
1550                     if (exe_ctx)
1551                     {
1552                         if (process)
1553                         {
1554                             lldb::addr_t pointer_addr = stack.back().GetScalar().ULongLong(LLDB_INVALID_ADDRESS);
1555                             uint8_t addr_bytes[sizeof(lldb::addr_t)];
1556                             Error error;
1557                             if (process->ReadMemory(pointer_addr, &addr_bytes, size, error) == size)
1558                             {
1559                                 DataExtractor addr_data(addr_bytes, sizeof(addr_bytes), process->GetByteOrder(), size);
1560                                 lldb::offset_t addr_data_offset = 0;
1561                                 switch (size)
1562                                 {
1563                                     case 1: stack.back().GetScalar() = addr_data.GetU8(&addr_data_offset); break;
1564                                     case 2: stack.back().GetScalar() = addr_data.GetU16(&addr_data_offset); break;
1565                                     case 4: stack.back().GetScalar() = addr_data.GetU32(&addr_data_offset); break;
1566                                     case 8: stack.back().GetScalar() = addr_data.GetU64(&addr_data_offset); break;
1567                                     default: stack.back().GetScalar() = addr_data.GetPointer(&addr_data_offset);
1568                                 }
1569                                 stack.back().ClearContext();
1570                             }
1571                             else
1572                             {
1573                                 if (error_ptr)
1574                                     error_ptr->SetErrorStringWithFormat ("Failed to dereference pointer from 0x%" PRIx64 " for DW_OP_deref: %s\n",
1575                                                                          pointer_addr,
1576                                                                          error.AsCString());
1577                                 return false;
1578                             }
1579                         }
1580                         else
1581                         {
1582                             if (error_ptr)
1583                                 error_ptr->SetErrorStringWithFormat ("NULL process for DW_OP_deref.\n");
1584                             return false;
1585                         }
1586                     }
1587                     else
1588                     {
1589                         if (error_ptr)
1590                             error_ptr->SetErrorStringWithFormat ("NULL execution context for DW_OP_deref.\n");
1591                         return false;
1592                     }
1593                     break;
1594 
1595                 default:
1596                     break;
1597                 }
1598 
1599             }
1600             break;
1601 
1602         //----------------------------------------------------------------------
1603         // OPCODE: DW_OP_xderef_size
1604         // OPERANDS: 1
1605         //  1 - uint8_t that specifies the size of the data to dereference.
1606         // DESCRIPTION: Behaves like the DW_OP_xderef operation: the entry at
1607         // the top of the stack is treated as an address. The second stack
1608         // entry is treated as an "address space identifier" for those
1609         // architectures that support multiple address spaces. The top two
1610         // stack elements are popped, a data item is retrieved through an
1611         // implementation-defined address calculation and pushed as the new
1612         // stack top. In the DW_OP_xderef_size operation, however, the size in
1613         // bytes of the data retrieved from the dereferenced address is
1614         // specified by the single operand. This operand is a 1-byte unsigned
1615         // integral constant whose value may not be larger than the size of an
1616         // address on the target machine. The data retrieved is zero extended
1617         // to the size of an address on the target machine before being pushed
1618         // on the expression stack.
1619         //----------------------------------------------------------------------
1620         case DW_OP_xderef_size:
1621             if (error_ptr)
1622                 error_ptr->SetErrorString("Unimplemented opcode: DW_OP_xderef_size.");
1623             return false;
1624         //----------------------------------------------------------------------
1625         // OPCODE: DW_OP_xderef
1626         // OPERANDS: none
1627         // DESCRIPTION: Provides an extended dereference mechanism. The entry at
1628         // the top of the stack is treated as an address. The second stack entry
1629         // is treated as an "address space identifier" for those architectures
1630         // that support multiple address spaces. The top two stack elements are
1631         // popped, a data item is retrieved through an implementation-defined
1632         // address calculation and pushed as the new stack top. The size of the
1633         // data retrieved from the dereferenced address is the size of an address
1634         // on the target machine.
1635         //----------------------------------------------------------------------
1636         case DW_OP_xderef:
1637             if (error_ptr)
1638                 error_ptr->SetErrorString("Unimplemented opcode: DW_OP_xderef.");
1639             return false;
1640 
1641         //----------------------------------------------------------------------
1642         // All DW_OP_constXXX opcodes have a single operand as noted below:
1643         //
1644         // Opcode           Operand 1
1645         // ---------------  ----------------------------------------------------
1646         // DW_OP_const1u    1-byte unsigned integer constant
1647         // DW_OP_const1s    1-byte signed integer constant
1648         // DW_OP_const2u    2-byte unsigned integer constant
1649         // DW_OP_const2s    2-byte signed integer constant
1650         // DW_OP_const4u    4-byte unsigned integer constant
1651         // DW_OP_const4s    4-byte signed integer constant
1652         // DW_OP_const8u    8-byte unsigned integer constant
1653         // DW_OP_const8s    8-byte signed integer constant
1654         // DW_OP_constu     unsigned LEB128 integer constant
1655         // DW_OP_consts     signed LEB128 integer constant
1656         //----------------------------------------------------------------------
1657         case DW_OP_const1u             :    stack.push_back(Scalar(( uint8_t)opcodes.GetU8 (&offset))); break;
1658         case DW_OP_const1s             :    stack.push_back(Scalar((  int8_t)opcodes.GetU8 (&offset))); break;
1659         case DW_OP_const2u             :    stack.push_back(Scalar((uint16_t)opcodes.GetU16 (&offset))); break;
1660         case DW_OP_const2s             :    stack.push_back(Scalar(( int16_t)opcodes.GetU16 (&offset))); break;
1661         case DW_OP_const4u             :    stack.push_back(Scalar((uint32_t)opcodes.GetU32 (&offset))); break;
1662         case DW_OP_const4s             :    stack.push_back(Scalar(( int32_t)opcodes.GetU32 (&offset))); break;
1663         case DW_OP_const8u             :    stack.push_back(Scalar((uint64_t)opcodes.GetU64 (&offset))); break;
1664         case DW_OP_const8s             :    stack.push_back(Scalar(( int64_t)opcodes.GetU64 (&offset))); break;
1665         case DW_OP_constu              :    stack.push_back(Scalar(opcodes.GetULEB128 (&offset))); break;
1666         case DW_OP_consts              :    stack.push_back(Scalar(opcodes.GetSLEB128 (&offset))); break;
1667 
1668         //----------------------------------------------------------------------
1669         // OPCODE: DW_OP_dup
1670         // OPERANDS: none
1671         // DESCRIPTION: duplicates the value at the top of the stack
1672         //----------------------------------------------------------------------
1673         case DW_OP_dup:
1674             if (stack.empty())
1675             {
1676                 if (error_ptr)
1677                     error_ptr->SetErrorString("Expression stack empty for DW_OP_dup.");
1678                 return false;
1679             }
1680             else
1681                 stack.push_back(stack.back());
1682             break;
1683 
1684         //----------------------------------------------------------------------
1685         // OPCODE: DW_OP_drop
1686         // OPERANDS: none
1687         // DESCRIPTION: pops the value at the top of the stack
1688         //----------------------------------------------------------------------
1689         case DW_OP_drop:
1690             if (stack.empty())
1691             {
1692                 if (error_ptr)
1693                     error_ptr->SetErrorString("Expression stack empty for DW_OP_drop.");
1694                 return false;
1695             }
1696             else
1697                 stack.pop_back();
1698             break;
1699 
1700         //----------------------------------------------------------------------
1701         // OPCODE: DW_OP_over
1702         // OPERANDS: none
1703         // DESCRIPTION: Duplicates the entry currently second in the stack at
1704         // the top of the stack.
1705         //----------------------------------------------------------------------
1706         case DW_OP_over:
1707             if (stack.size() < 2)
1708             {
1709                 if (error_ptr)
1710                     error_ptr->SetErrorString("Expression stack needs at least 2 items for DW_OP_over.");
1711                 return false;
1712             }
1713             else
1714                 stack.push_back(stack[stack.size() - 2]);
1715             break;
1716 
1717 
1718         //----------------------------------------------------------------------
1719         // OPCODE: DW_OP_pick
1720         // OPERANDS: uint8_t index into the current stack
1721         // DESCRIPTION: The stack entry with the specified index (0 through 255,
1722         // inclusive) is pushed on the stack
1723         //----------------------------------------------------------------------
1724         case DW_OP_pick:
1725             {
1726                 uint8_t pick_idx = opcodes.GetU8(&offset);
1727                 if (pick_idx < stack.size())
1728                     stack.push_back(stack[pick_idx]);
1729                 else
1730                 {
1731                     if (error_ptr)
1732                         error_ptr->SetErrorStringWithFormat("Index %u out of range for DW_OP_pick.\n", pick_idx);
1733                     return false;
1734                 }
1735             }
1736             break;
1737 
1738         //----------------------------------------------------------------------
1739         // OPCODE: DW_OP_swap
1740         // OPERANDS: none
1741         // DESCRIPTION: swaps the top two stack entries. The entry at the top
1742         // of the stack becomes the second stack entry, and the second entry
1743         // becomes the top of the stack
1744         //----------------------------------------------------------------------
1745         case DW_OP_swap:
1746             if (stack.size() < 2)
1747             {
1748                 if (error_ptr)
1749                     error_ptr->SetErrorString("Expression stack needs at least 2 items for DW_OP_swap.");
1750                 return false;
1751             }
1752             else
1753             {
1754                 tmp = stack.back();
1755                 stack.back() = stack[stack.size() - 2];
1756                 stack[stack.size() - 2] = tmp;
1757             }
1758             break;
1759 
1760         //----------------------------------------------------------------------
1761         // OPCODE: DW_OP_rot
1762         // OPERANDS: none
1763         // DESCRIPTION: Rotates the first three stack entries. The entry at
1764         // the top of the stack becomes the third stack entry, the second
1765         // entry becomes the top of the stack, and the third entry becomes
1766         // the second entry.
1767         //----------------------------------------------------------------------
1768         case DW_OP_rot:
1769             if (stack.size() < 3)
1770             {
1771                 if (error_ptr)
1772                     error_ptr->SetErrorString("Expression stack needs at least 3 items for DW_OP_rot.");
1773                 return false;
1774             }
1775             else
1776             {
1777                 size_t last_idx = stack.size() - 1;
1778                 Value old_top = stack[last_idx];
1779                 stack[last_idx] = stack[last_idx - 1];
1780                 stack[last_idx - 1] = stack[last_idx - 2];
1781                 stack[last_idx - 2] = old_top;
1782             }
1783             break;
1784 
1785         //----------------------------------------------------------------------
1786         // OPCODE: DW_OP_abs
1787         // OPERANDS: none
1788         // DESCRIPTION: pops the top stack entry, interprets it as a signed
1789         // value and pushes its absolute value. If the absolute value can not be
1790         // represented, the result is undefined.
1791         //----------------------------------------------------------------------
1792         case DW_OP_abs:
1793             if (stack.empty())
1794             {
1795                 if (error_ptr)
1796                     error_ptr->SetErrorString("Expression stack needs at least 1 item for DW_OP_abs.");
1797                 return false;
1798             }
1799             else if (stack.back().ResolveValue(exe_ctx).AbsoluteValue() == false)
1800             {
1801                 if (error_ptr)
1802                     error_ptr->SetErrorString("Failed to take the absolute value of the first stack item.");
1803                 return false;
1804             }
1805             break;
1806 
1807         //----------------------------------------------------------------------
1808         // OPCODE: DW_OP_and
1809         // OPERANDS: none
1810         // DESCRIPTION: pops the top two stack values, performs a bitwise and
1811         // operation on the two, and pushes the result.
1812         //----------------------------------------------------------------------
1813         case DW_OP_and:
1814             if (stack.size() < 2)
1815             {
1816                 if (error_ptr)
1817                     error_ptr->SetErrorString("Expression stack needs at least 2 items for DW_OP_and.");
1818                 return false;
1819             }
1820             else
1821             {
1822                 tmp = stack.back();
1823                 stack.pop_back();
1824                 stack.back().ResolveValue(exe_ctx) = stack.back().ResolveValue(exe_ctx) & tmp.ResolveValue(exe_ctx);
1825             }
1826             break;
1827 
1828         //----------------------------------------------------------------------
1829         // OPCODE: DW_OP_div
1830         // OPERANDS: none
1831         // DESCRIPTION: pops the top two stack values, divides the former second
1832         // entry by the former top of the stack using signed division, and
1833         // pushes the result.
1834         //----------------------------------------------------------------------
1835         case DW_OP_div:
1836             if (stack.size() < 2)
1837             {
1838                 if (error_ptr)
1839                     error_ptr->SetErrorString("Expression stack needs at least 2 items for DW_OP_div.");
1840                 return false;
1841             }
1842             else
1843             {
1844                 tmp = stack.back();
1845                 if (tmp.ResolveValue(exe_ctx).IsZero())
1846                 {
1847                     if (error_ptr)
1848                         error_ptr->SetErrorString("Divide by zero.");
1849                     return false;
1850                 }
1851                 else
1852                 {
1853                     stack.pop_back();
1854                     stack.back() = stack.back().ResolveValue(exe_ctx) / tmp.ResolveValue(exe_ctx);
1855                     if (!stack.back().ResolveValue(exe_ctx).IsValid())
1856                     {
1857                         if (error_ptr)
1858                             error_ptr->SetErrorString("Divide failed.");
1859                         return false;
1860                     }
1861                 }
1862             }
1863             break;
1864 
1865         //----------------------------------------------------------------------
1866         // OPCODE: DW_OP_minus
1867         // OPERANDS: none
1868         // DESCRIPTION: pops the top two stack values, subtracts the former top
1869         // of the stack from the former second entry, and pushes the result.
1870         //----------------------------------------------------------------------
1871         case DW_OP_minus:
1872             if (stack.size() < 2)
1873             {
1874                 if (error_ptr)
1875                     error_ptr->SetErrorString("Expression stack needs at least 2 items for DW_OP_minus.");
1876                 return false;
1877             }
1878             else
1879             {
1880                 tmp = stack.back();
1881                 stack.pop_back();
1882                 stack.back().ResolveValue(exe_ctx) = stack.back().ResolveValue(exe_ctx) - tmp.ResolveValue(exe_ctx);
1883             }
1884             break;
1885 
1886         //----------------------------------------------------------------------
1887         // OPCODE: DW_OP_mod
1888         // OPERANDS: none
1889         // DESCRIPTION: pops the top two stack values and pushes the result of
1890         // the calculation: former second stack entry modulo the former top of
1891         // the stack.
1892         //----------------------------------------------------------------------
1893         case DW_OP_mod:
1894             if (stack.size() < 2)
1895             {
1896                 if (error_ptr)
1897                     error_ptr->SetErrorString("Expression stack needs at least 2 items for DW_OP_mod.");
1898                 return false;
1899             }
1900             else
1901             {
1902                 tmp = stack.back();
1903                 stack.pop_back();
1904                 stack.back().ResolveValue(exe_ctx) = stack.back().ResolveValue(exe_ctx) % tmp.ResolveValue(exe_ctx);
1905             }
1906             break;
1907 
1908 
1909         //----------------------------------------------------------------------
1910         // OPCODE: DW_OP_mul
1911         // OPERANDS: none
1912         // DESCRIPTION: pops the top two stack entries, multiplies them
1913         // together, and pushes the result.
1914         //----------------------------------------------------------------------
1915         case DW_OP_mul:
1916             if (stack.size() < 2)
1917             {
1918                 if (error_ptr)
1919                     error_ptr->SetErrorString("Expression stack needs at least 2 items for DW_OP_mul.");
1920                 return false;
1921             }
1922             else
1923             {
1924                 tmp = stack.back();
1925                 stack.pop_back();
1926                 stack.back().ResolveValue(exe_ctx) = stack.back().ResolveValue(exe_ctx) * tmp.ResolveValue(exe_ctx);
1927             }
1928             break;
1929 
1930         //----------------------------------------------------------------------
1931         // OPCODE: DW_OP_neg
1932         // OPERANDS: none
1933         // DESCRIPTION: pops the top stack entry, and pushes its negation.
1934         //----------------------------------------------------------------------
1935         case DW_OP_neg:
1936             if (stack.empty())
1937             {
1938                 if (error_ptr)
1939                     error_ptr->SetErrorString("Expression stack needs at least 1 item for DW_OP_neg.");
1940                 return false;
1941             }
1942             else
1943             {
1944                 if (stack.back().ResolveValue(exe_ctx).UnaryNegate() == false)
1945                 {
1946                     if (error_ptr)
1947                         error_ptr->SetErrorString("Unary negate failed.");
1948                     return false;
1949                 }
1950             }
1951             break;
1952 
1953         //----------------------------------------------------------------------
1954         // OPCODE: DW_OP_not
1955         // OPERANDS: none
1956         // DESCRIPTION: pops the top stack entry, and pushes its bitwise
1957         // complement
1958         //----------------------------------------------------------------------
1959         case DW_OP_not:
1960             if (stack.empty())
1961             {
1962                 if (error_ptr)
1963                     error_ptr->SetErrorString("Expression stack needs at least 1 item for DW_OP_not.");
1964                 return false;
1965             }
1966             else
1967             {
1968                 if (stack.back().ResolveValue(exe_ctx).OnesComplement() == false)
1969                 {
1970                     if (error_ptr)
1971                         error_ptr->SetErrorString("Logical NOT failed.");
1972                     return false;
1973                 }
1974             }
1975             break;
1976 
1977         //----------------------------------------------------------------------
1978         // OPCODE: DW_OP_or
1979         // OPERANDS: none
1980         // DESCRIPTION: pops the top two stack entries, performs a bitwise or
1981         // operation on the two, and pushes the result.
1982         //----------------------------------------------------------------------
1983         case DW_OP_or:
1984             if (stack.size() < 2)
1985             {
1986                 if (error_ptr)
1987                     error_ptr->SetErrorString("Expression stack needs at least 2 items for DW_OP_or.");
1988                 return false;
1989             }
1990             else
1991             {
1992                 tmp = stack.back();
1993                 stack.pop_back();
1994                 stack.back().ResolveValue(exe_ctx) = stack.back().ResolveValue(exe_ctx) | tmp.ResolveValue(exe_ctx);
1995             }
1996             break;
1997 
1998         //----------------------------------------------------------------------
1999         // OPCODE: DW_OP_plus
2000         // OPERANDS: none
2001         // DESCRIPTION: pops the top two stack entries, adds them together, and
2002         // pushes the result.
2003         //----------------------------------------------------------------------
2004         case DW_OP_plus:
2005             if (stack.size() < 2)
2006             {
2007                 if (error_ptr)
2008                     error_ptr->SetErrorString("Expression stack needs at least 2 items for DW_OP_plus.");
2009                 return false;
2010             }
2011             else
2012             {
2013                 tmp = stack.back();
2014                 stack.pop_back();
2015                 stack.back().ResolveValue(exe_ctx) = stack.back().ResolveValue(exe_ctx) + tmp.ResolveValue(exe_ctx);
2016             }
2017             break;
2018 
2019         //----------------------------------------------------------------------
2020         // OPCODE: DW_OP_plus_uconst
2021         // OPERANDS: none
2022         // DESCRIPTION: pops the top stack entry, adds it to the unsigned LEB128
2023         // constant operand and pushes the result.
2024         //----------------------------------------------------------------------
2025         case DW_OP_plus_uconst:
2026             if (stack.empty())
2027             {
2028                 if (error_ptr)
2029                     error_ptr->SetErrorString("Expression stack needs at least 1 item for DW_OP_plus_uconst.");
2030                 return false;
2031             }
2032             else
2033             {
2034                 const uint64_t uconst_value = opcodes.GetULEB128(&offset);
2035                 // Implicit conversion from a UINT to a Scalar...
2036                 stack.back().ResolveValue(exe_ctx) += uconst_value;
2037                 if (!stack.back().ResolveValue(exe_ctx).IsValid())
2038                 {
2039                     if (error_ptr)
2040                         error_ptr->SetErrorString("DW_OP_plus_uconst failed.");
2041                     return false;
2042                 }
2043             }
2044             break;
2045 
2046         //----------------------------------------------------------------------
2047         // OPCODE: DW_OP_shl
2048         // OPERANDS: none
2049         // DESCRIPTION:  pops the top two stack entries, shifts the former
2050         // second entry left by the number of bits specified by the former top
2051         // of the stack, and pushes the result.
2052         //----------------------------------------------------------------------
2053         case DW_OP_shl:
2054             if (stack.size() < 2)
2055             {
2056                 if (error_ptr)
2057                     error_ptr->SetErrorString("Expression stack needs at least 2 items for DW_OP_shl.");
2058                 return false;
2059             }
2060             else
2061             {
2062                 tmp = stack.back();
2063                 stack.pop_back();
2064                 stack.back().ResolveValue(exe_ctx) <<= tmp.ResolveValue(exe_ctx);
2065             }
2066             break;
2067 
2068         //----------------------------------------------------------------------
2069         // OPCODE: DW_OP_shr
2070         // OPERANDS: none
2071         // DESCRIPTION: pops the top two stack entries, shifts the former second
2072         // entry right logically (filling with zero bits) by the number of bits
2073         // specified by the former top of the stack, and pushes the result.
2074         //----------------------------------------------------------------------
2075         case DW_OP_shr:
2076             if (stack.size() < 2)
2077             {
2078                 if (error_ptr)
2079                     error_ptr->SetErrorString("Expression stack needs at least 2 items for DW_OP_shr.");
2080                 return false;
2081             }
2082             else
2083             {
2084                 tmp = stack.back();
2085                 stack.pop_back();
2086                 if (stack.back().ResolveValue(exe_ctx).ShiftRightLogical(tmp.ResolveValue(exe_ctx)) == false)
2087                 {
2088                     if (error_ptr)
2089                         error_ptr->SetErrorString("DW_OP_shr failed.");
2090                     return false;
2091                 }
2092             }
2093             break;
2094 
2095         //----------------------------------------------------------------------
2096         // OPCODE: DW_OP_shra
2097         // OPERANDS: none
2098         // DESCRIPTION: pops the top two stack entries, shifts the former second
2099         // entry right arithmetically (divide the magnitude by 2, keep the same
2100         // sign for the result) by the number of bits specified by the former
2101         // top of the stack, and pushes the result.
2102         //----------------------------------------------------------------------
2103         case DW_OP_shra:
2104             if (stack.size() < 2)
2105             {
2106                 if (error_ptr)
2107                     error_ptr->SetErrorString("Expression stack needs at least 2 items for DW_OP_shra.");
2108                 return false;
2109             }
2110             else
2111             {
2112                 tmp = stack.back();
2113                 stack.pop_back();
2114                 stack.back().ResolveValue(exe_ctx) >>= tmp.ResolveValue(exe_ctx);
2115             }
2116             break;
2117 
2118         //----------------------------------------------------------------------
2119         // OPCODE: DW_OP_xor
2120         // OPERANDS: none
2121         // DESCRIPTION: pops the top two stack entries, performs the bitwise
2122         // exclusive-or operation on the two, and pushes the result.
2123         //----------------------------------------------------------------------
2124         case DW_OP_xor:
2125             if (stack.size() < 2)
2126             {
2127                 if (error_ptr)
2128                     error_ptr->SetErrorString("Expression stack needs at least 2 items for DW_OP_xor.");
2129                 return false;
2130             }
2131             else
2132             {
2133                 tmp = stack.back();
2134                 stack.pop_back();
2135                 stack.back().ResolveValue(exe_ctx) = stack.back().ResolveValue(exe_ctx) ^ tmp.ResolveValue(exe_ctx);
2136             }
2137             break;
2138 
2139 
2140         //----------------------------------------------------------------------
2141         // OPCODE: DW_OP_skip
2142         // OPERANDS: int16_t
2143         // DESCRIPTION:  An unconditional branch. Its single operand is a 2-byte
2144         // signed integer constant. The 2-byte constant is the number of bytes
2145         // of the DWARF expression to skip forward or backward from the current
2146         // operation, beginning after the 2-byte constant.
2147         //----------------------------------------------------------------------
2148         case DW_OP_skip:
2149             {
2150                 int16_t skip_offset = (int16_t)opcodes.GetU16(&offset);
2151                 lldb::offset_t new_offset = offset + skip_offset;
2152                 if (new_offset >= opcodes_offset && new_offset < end_offset)
2153                     offset = new_offset;
2154                 else
2155                 {
2156                     if (error_ptr)
2157                         error_ptr->SetErrorString("Invalid opcode offset in DW_OP_skip.");
2158                     return false;
2159                 }
2160             }
2161             break;
2162 
2163         //----------------------------------------------------------------------
2164         // OPCODE: DW_OP_bra
2165         // OPERANDS: int16_t
2166         // DESCRIPTION: A conditional branch. Its single operand is a 2-byte
2167         // signed integer constant. This operation pops the top of stack. If
2168         // the value popped is not the constant 0, the 2-byte constant operand
2169         // is the number of bytes of the DWARF expression to skip forward or
2170         // backward from the current operation, beginning after the 2-byte
2171         // constant.
2172         //----------------------------------------------------------------------
2173         case DW_OP_bra:
2174             {
2175                 tmp = stack.back();
2176                 stack.pop_back();
2177                 int16_t bra_offset = (int16_t)opcodes.GetU16(&offset);
2178                 Scalar zero(0);
2179                 if (tmp.ResolveValue(exe_ctx) != zero)
2180                 {
2181                     lldb::offset_t new_offset = offset + bra_offset;
2182                     if (new_offset >= opcodes_offset && new_offset < end_offset)
2183                         offset = new_offset;
2184                     else
2185                     {
2186                         if (error_ptr)
2187                             error_ptr->SetErrorString("Invalid opcode offset in DW_OP_bra.");
2188                         return false;
2189                     }
2190                 }
2191             }
2192             break;
2193 
2194         //----------------------------------------------------------------------
2195         // OPCODE: DW_OP_eq
2196         // OPERANDS: none
2197         // DESCRIPTION: pops the top two stack values, compares using the
2198         // equals (==) operator.
2199         // STACK RESULT: push the constant value 1 onto the stack if the result
2200         // of the operation is true or the constant value 0 if the result of the
2201         // operation is false.
2202         //----------------------------------------------------------------------
2203         case DW_OP_eq:
2204             if (stack.size() < 2)
2205             {
2206                 if (error_ptr)
2207                     error_ptr->SetErrorString("Expression stack needs at least 2 items for DW_OP_eq.");
2208                 return false;
2209             }
2210             else
2211             {
2212                 tmp = stack.back();
2213                 stack.pop_back();
2214                 stack.back().ResolveValue(exe_ctx) = stack.back().ResolveValue(exe_ctx) == tmp.ResolveValue(exe_ctx);
2215             }
2216             break;
2217 
2218         //----------------------------------------------------------------------
2219         // OPCODE: DW_OP_ge
2220         // OPERANDS: none
2221         // DESCRIPTION: pops the top two stack values, compares using the
2222         // greater than or equal to (>=) operator.
2223         // STACK RESULT: push the constant value 1 onto the stack if the result
2224         // of the operation is true or the constant value 0 if the result of the
2225         // operation is false.
2226         //----------------------------------------------------------------------
2227         case DW_OP_ge:
2228             if (stack.size() < 2)
2229             {
2230                 if (error_ptr)
2231                     error_ptr->SetErrorString("Expression stack needs at least 2 items for DW_OP_ge.");
2232                 return false;
2233             }
2234             else
2235             {
2236                 tmp = stack.back();
2237                 stack.pop_back();
2238                 stack.back().ResolveValue(exe_ctx) = stack.back().ResolveValue(exe_ctx) >= tmp.ResolveValue(exe_ctx);
2239             }
2240             break;
2241 
2242         //----------------------------------------------------------------------
2243         // OPCODE: DW_OP_gt
2244         // OPERANDS: none
2245         // DESCRIPTION: pops the top two stack values, compares using the
2246         // greater than (>) operator.
2247         // STACK RESULT: push the constant value 1 onto the stack if the result
2248         // of the operation is true or the constant value 0 if the result of the
2249         // operation is false.
2250         //----------------------------------------------------------------------
2251         case DW_OP_gt:
2252             if (stack.size() < 2)
2253             {
2254                 if (error_ptr)
2255                     error_ptr->SetErrorString("Expression stack needs at least 2 items for DW_OP_gt.");
2256                 return false;
2257             }
2258             else
2259             {
2260                 tmp = stack.back();
2261                 stack.pop_back();
2262                 stack.back().ResolveValue(exe_ctx) = stack.back().ResolveValue(exe_ctx) > tmp.ResolveValue(exe_ctx);
2263             }
2264             break;
2265 
2266         //----------------------------------------------------------------------
2267         // OPCODE: DW_OP_le
2268         // OPERANDS: none
2269         // DESCRIPTION: pops the top two stack values, compares using the
2270         // less than or equal to (<=) operator.
2271         // STACK RESULT: push the constant value 1 onto the stack if the result
2272         // of the operation is true or the constant value 0 if the result of the
2273         // operation is false.
2274         //----------------------------------------------------------------------
2275         case DW_OP_le:
2276             if (stack.size() < 2)
2277             {
2278                 if (error_ptr)
2279                     error_ptr->SetErrorString("Expression stack needs at least 2 items for DW_OP_le.");
2280                 return false;
2281             }
2282             else
2283             {
2284                 tmp = stack.back();
2285                 stack.pop_back();
2286                 stack.back().ResolveValue(exe_ctx) = stack.back().ResolveValue(exe_ctx) <= tmp.ResolveValue(exe_ctx);
2287             }
2288             break;
2289 
2290         //----------------------------------------------------------------------
2291         // OPCODE: DW_OP_lt
2292         // OPERANDS: none
2293         // DESCRIPTION: pops the top two stack values, compares using the
2294         // less than (<) operator.
2295         // STACK RESULT: push the constant value 1 onto the stack if the result
2296         // of the operation is true or the constant value 0 if the result of the
2297         // operation is false.
2298         //----------------------------------------------------------------------
2299         case DW_OP_lt:
2300             if (stack.size() < 2)
2301             {
2302                 if (error_ptr)
2303                     error_ptr->SetErrorString("Expression stack needs at least 2 items for DW_OP_lt.");
2304                 return false;
2305             }
2306             else
2307             {
2308                 tmp = stack.back();
2309                 stack.pop_back();
2310                 stack.back().ResolveValue(exe_ctx) = stack.back().ResolveValue(exe_ctx) < tmp.ResolveValue(exe_ctx);
2311             }
2312             break;
2313 
2314         //----------------------------------------------------------------------
2315         // OPCODE: DW_OP_ne
2316         // OPERANDS: none
2317         // DESCRIPTION: pops the top two stack values, compares using the
2318         // not equal (!=) operator.
2319         // STACK RESULT: push the constant value 1 onto the stack if the result
2320         // of the operation is true or the constant value 0 if the result of the
2321         // operation is false.
2322         //----------------------------------------------------------------------
2323         case DW_OP_ne:
2324             if (stack.size() < 2)
2325             {
2326                 if (error_ptr)
2327                     error_ptr->SetErrorString("Expression stack needs at least 2 items for DW_OP_ne.");
2328                 return false;
2329             }
2330             else
2331             {
2332                 tmp = stack.back();
2333                 stack.pop_back();
2334                 stack.back().ResolveValue(exe_ctx) = stack.back().ResolveValue(exe_ctx) != tmp.ResolveValue(exe_ctx);
2335             }
2336             break;
2337 
2338         //----------------------------------------------------------------------
2339         // OPCODE: DW_OP_litn
2340         // OPERANDS: none
2341         // DESCRIPTION: encode the unsigned literal values from 0 through 31.
2342         // STACK RESULT: push the unsigned literal constant value onto the top
2343         // of the stack.
2344         //----------------------------------------------------------------------
2345         case DW_OP_lit0:
2346         case DW_OP_lit1:
2347         case DW_OP_lit2:
2348         case DW_OP_lit3:
2349         case DW_OP_lit4:
2350         case DW_OP_lit5:
2351         case DW_OP_lit6:
2352         case DW_OP_lit7:
2353         case DW_OP_lit8:
2354         case DW_OP_lit9:
2355         case DW_OP_lit10:
2356         case DW_OP_lit11:
2357         case DW_OP_lit12:
2358         case DW_OP_lit13:
2359         case DW_OP_lit14:
2360         case DW_OP_lit15:
2361         case DW_OP_lit16:
2362         case DW_OP_lit17:
2363         case DW_OP_lit18:
2364         case DW_OP_lit19:
2365         case DW_OP_lit20:
2366         case DW_OP_lit21:
2367         case DW_OP_lit22:
2368         case DW_OP_lit23:
2369         case DW_OP_lit24:
2370         case DW_OP_lit25:
2371         case DW_OP_lit26:
2372         case DW_OP_lit27:
2373         case DW_OP_lit28:
2374         case DW_OP_lit29:
2375         case DW_OP_lit30:
2376         case DW_OP_lit31:
2377             stack.push_back(Scalar(op - DW_OP_lit0));
2378             break;
2379 
2380         //----------------------------------------------------------------------
2381         // OPCODE: DW_OP_regN
2382         // OPERANDS: none
2383         // DESCRIPTION: Push the value in register n on the top of the stack.
2384         //----------------------------------------------------------------------
2385         case DW_OP_reg0:
2386         case DW_OP_reg1:
2387         case DW_OP_reg2:
2388         case DW_OP_reg3:
2389         case DW_OP_reg4:
2390         case DW_OP_reg5:
2391         case DW_OP_reg6:
2392         case DW_OP_reg7:
2393         case DW_OP_reg8:
2394         case DW_OP_reg9:
2395         case DW_OP_reg10:
2396         case DW_OP_reg11:
2397         case DW_OP_reg12:
2398         case DW_OP_reg13:
2399         case DW_OP_reg14:
2400         case DW_OP_reg15:
2401         case DW_OP_reg16:
2402         case DW_OP_reg17:
2403         case DW_OP_reg18:
2404         case DW_OP_reg19:
2405         case DW_OP_reg20:
2406         case DW_OP_reg21:
2407         case DW_OP_reg22:
2408         case DW_OP_reg23:
2409         case DW_OP_reg24:
2410         case DW_OP_reg25:
2411         case DW_OP_reg26:
2412         case DW_OP_reg27:
2413         case DW_OP_reg28:
2414         case DW_OP_reg29:
2415         case DW_OP_reg30:
2416         case DW_OP_reg31:
2417             {
2418                 reg_num = op - DW_OP_reg0;
2419 
2420                 if (ReadRegisterValueAsScalar (reg_ctx, reg_kind, reg_num, error_ptr, tmp))
2421                     stack.push_back(tmp);
2422                 else
2423                     return false;
2424             }
2425             break;
2426         //----------------------------------------------------------------------
2427         // OPCODE: DW_OP_regx
2428         // OPERANDS:
2429         //      ULEB128 literal operand that encodes the register.
2430         // DESCRIPTION: Push the value in register on the top of the stack.
2431         //----------------------------------------------------------------------
2432         case DW_OP_regx:
2433             {
2434                 reg_num = opcodes.GetULEB128(&offset);
2435                 if (ReadRegisterValueAsScalar (reg_ctx, reg_kind, reg_num, error_ptr, tmp))
2436                     stack.push_back(tmp);
2437                 else
2438                     return false;
2439             }
2440             break;
2441 
2442         //----------------------------------------------------------------------
2443         // OPCODE: DW_OP_bregN
2444         // OPERANDS:
2445         //      SLEB128 offset from register N
2446         // DESCRIPTION: Value is in memory at the address specified by register
2447         // N plus an offset.
2448         //----------------------------------------------------------------------
2449         case DW_OP_breg0:
2450         case DW_OP_breg1:
2451         case DW_OP_breg2:
2452         case DW_OP_breg3:
2453         case DW_OP_breg4:
2454         case DW_OP_breg5:
2455         case DW_OP_breg6:
2456         case DW_OP_breg7:
2457         case DW_OP_breg8:
2458         case DW_OP_breg9:
2459         case DW_OP_breg10:
2460         case DW_OP_breg11:
2461         case DW_OP_breg12:
2462         case DW_OP_breg13:
2463         case DW_OP_breg14:
2464         case DW_OP_breg15:
2465         case DW_OP_breg16:
2466         case DW_OP_breg17:
2467         case DW_OP_breg18:
2468         case DW_OP_breg19:
2469         case DW_OP_breg20:
2470         case DW_OP_breg21:
2471         case DW_OP_breg22:
2472         case DW_OP_breg23:
2473         case DW_OP_breg24:
2474         case DW_OP_breg25:
2475         case DW_OP_breg26:
2476         case DW_OP_breg27:
2477         case DW_OP_breg28:
2478         case DW_OP_breg29:
2479         case DW_OP_breg30:
2480         case DW_OP_breg31:
2481             {
2482                 reg_num = op - DW_OP_breg0;
2483 
2484                 if (ReadRegisterValueAsScalar (reg_ctx, reg_kind, reg_num, error_ptr, tmp))
2485                 {
2486                     int64_t breg_offset = opcodes.GetSLEB128(&offset);
2487                     tmp.ResolveValue(exe_ctx) += (uint64_t)breg_offset;
2488                     tmp.ClearContext();
2489                     stack.push_back(tmp);
2490                     stack.back().SetValueType (Value::eValueTypeLoadAddress);
2491                 }
2492                 else
2493                     return false;
2494             }
2495             break;
2496         //----------------------------------------------------------------------
2497         // OPCODE: DW_OP_bregx
2498         // OPERANDS: 2
2499         //      ULEB128 literal operand that encodes the register.
2500         //      SLEB128 offset from register N
2501         // DESCRIPTION: Value is in memory at the address specified by register
2502         // N plus an offset.
2503         //----------------------------------------------------------------------
2504         case DW_OP_bregx:
2505             {
2506                 reg_num = opcodes.GetULEB128(&offset);
2507 
2508                 if (ReadRegisterValueAsScalar (reg_ctx, reg_kind, reg_num, error_ptr, tmp))
2509                 {
2510                     int64_t breg_offset = opcodes.GetSLEB128(&offset);
2511                     tmp.ResolveValue(exe_ctx) += (uint64_t)breg_offset;
2512                     tmp.ClearContext();
2513                     stack.push_back(tmp);
2514                     stack.back().SetValueType (Value::eValueTypeLoadAddress);
2515                 }
2516                 else
2517                     return false;
2518             }
2519             break;
2520 
2521         case DW_OP_fbreg:
2522             if (exe_ctx)
2523             {
2524                 if (frame)
2525                 {
2526                     Scalar value;
2527                     if (frame->GetFrameBaseValue(value, error_ptr))
2528                     {
2529                         int64_t fbreg_offset = opcodes.GetSLEB128(&offset);
2530                         value += fbreg_offset;
2531                         stack.push_back(value);
2532                         stack.back().SetValueType (Value::eValueTypeLoadAddress);
2533                     }
2534                     else
2535                         return false;
2536                 }
2537                 else
2538                 {
2539                     if (error_ptr)
2540                         error_ptr->SetErrorString ("Invalid stack frame in context for DW_OP_fbreg opcode.");
2541                     return false;
2542                 }
2543             }
2544             else
2545             {
2546                 if (error_ptr)
2547                     error_ptr->SetErrorStringWithFormat ("NULL execution context for DW_OP_fbreg.\n");
2548                 return false;
2549             }
2550 
2551             break;
2552 
2553         //----------------------------------------------------------------------
2554         // OPCODE: DW_OP_nop
2555         // OPERANDS: none
2556         // DESCRIPTION: A place holder. It has no effect on the location stack
2557         // or any of its values.
2558         //----------------------------------------------------------------------
2559         case DW_OP_nop:
2560             break;
2561 
2562         //----------------------------------------------------------------------
2563         // OPCODE: DW_OP_piece
2564         // OPERANDS: 1
2565         //      ULEB128: byte size of the piece
2566         // DESCRIPTION: The operand describes the size in bytes of the piece of
2567         // the object referenced by the DWARF expression whose result is at the
2568         // top of the stack. If the piece is located in a register, but does not
2569         // occupy the entire register, the placement of the piece within that
2570         // register is defined by the ABI.
2571         //
2572         // Many compilers store a single variable in sets of registers, or store
2573         // a variable partially in memory and partially in registers.
2574         // DW_OP_piece provides a way of describing how large a part of a
2575         // variable a particular DWARF expression refers to.
2576         //----------------------------------------------------------------------
2577         case DW_OP_piece:
2578             {
2579                 const uint64_t piece_byte_size = opcodes.GetULEB128(&offset);
2580 
2581                 if (piece_byte_size > 0)
2582                 {
2583                     Value curr_piece;
2584 
2585                     if (stack.empty())
2586                     {
2587                         // In a multi-piece expression, this means that the current piece is not available.
2588                         // Fill with zeros for now by resizing the data and appending it
2589                         curr_piece.ResizeData(piece_byte_size);
2590                         ::memset (curr_piece.GetBuffer().GetBytes(), 0, piece_byte_size);
2591                         pieces.AppendDataToHostBuffer(curr_piece);
2592                     }
2593                     else
2594                     {
2595                         Error error;
2596                         // Extract the current piece into "curr_piece"
2597                         Value curr_piece_source_value(stack.back());
2598                         stack.pop_back();
2599 
2600                         const Value::ValueType curr_piece_source_value_type = curr_piece_source_value.GetValueType();
2601                         switch (curr_piece_source_value_type)
2602                         {
2603                         case Value::eValueTypeLoadAddress:
2604                             if (process)
2605                             {
2606                                 if (curr_piece.ResizeData(piece_byte_size) == piece_byte_size)
2607                                 {
2608                                     lldb::addr_t load_addr = curr_piece_source_value.GetScalar().ULongLong(LLDB_INVALID_ADDRESS);
2609                                     if (process->ReadMemory(load_addr, curr_piece.GetBuffer().GetBytes(), piece_byte_size, error) != piece_byte_size)
2610                                     {
2611                                         if (error_ptr)
2612                                             error_ptr->SetErrorStringWithFormat ("failed to read memory DW_OP_piece(%" PRIu64 ") from 0x%" PRIx64,
2613                                                                                  piece_byte_size,
2614                                                                                  load_addr);
2615                                         return false;
2616                                     }
2617                                 }
2618                                 else
2619                                 {
2620                                     if (error_ptr)
2621                                         error_ptr->SetErrorStringWithFormat ("failed to resize the piece memory buffer for DW_OP_piece(%" PRIu64 ")", piece_byte_size);
2622                                     return false;
2623                                 }
2624                             }
2625                             break;
2626 
2627                         case Value::eValueTypeFileAddress:
2628                         case Value::eValueTypeHostAddress:
2629                             if (error_ptr)
2630                             {
2631                                 lldb::addr_t addr = curr_piece_source_value.GetScalar().ULongLong(LLDB_INVALID_ADDRESS);
2632                                 error_ptr->SetErrorStringWithFormat ("failed to read memory DW_OP_piece(%" PRIu64 ") from %s address 0x%" PRIx64,
2633                                                                      piece_byte_size,
2634                                                                      curr_piece_source_value.GetValueType() == Value::eValueTypeFileAddress ? "file" : "host",
2635                                                                      addr);
2636                             }
2637                             return false;
2638 
2639                         case Value::eValueTypeScalar:
2640                             {
2641                                 uint32_t bit_size = piece_byte_size * 8;
2642                                 uint32_t bit_offset = 0;
2643                                 if (!curr_piece_source_value.GetScalar().ExtractBitfield (bit_size, bit_offset))
2644                                 {
2645                                     if (error_ptr)
2646                                         error_ptr->SetErrorStringWithFormat("unable to extract %" PRIu64 " bytes from a %" PRIu64 " byte scalar value.", piece_byte_size, (uint64_t)curr_piece_source_value.GetScalar().GetByteSize());
2647                                     return false;
2648                                 }
2649                                 curr_piece = curr_piece_source_value;
2650                             }
2651                             break;
2652 
2653                         case Value::eValueTypeVector:
2654                             {
2655                                 if (curr_piece_source_value.GetVector().length >= piece_byte_size)
2656                                     curr_piece_source_value.GetVector().length = piece_byte_size;
2657                                 else
2658                                 {
2659                                     if (error_ptr)
2660                                         error_ptr->SetErrorStringWithFormat("unable to extract %" PRIu64 " bytes from a %" PRIu64 " byte vector value.", piece_byte_size, (uint64_t)curr_piece_source_value.GetVector().length);
2661                                     return false;
2662                                 }
2663                             }
2664                             break;
2665 
2666                         default:
2667                             if (error_ptr)
2668                                 error_ptr->SetErrorStringWithFormat ("unhandled value typpe for DW_OP_piece(%" PRIu64 ")", piece_byte_size);
2669                             return false;
2670 
2671                         }
2672 
2673                         // Check if this is the first piece?
2674                         if (op_piece_offset == 0)
2675                         {
2676                             // This is the first piece, we should push it back onto the stack so subsequent
2677                             // pieces will be able to access this piece and add to it
2678                             if (pieces.AppendDataToHostBuffer(curr_piece) == 0)
2679                             {
2680                                 if (error_ptr)
2681                                     error_ptr->SetErrorString("failed to append piece data");
2682                                 return false;
2683                             }
2684                         }
2685                         else if (!stack.empty())
2686                         {
2687                             // If this is the second or later piece there should be a value on the stack
2688                             if (pieces.GetBuffer().GetByteSize() != op_piece_offset)
2689                             {
2690                                 if (error_ptr)
2691                                     error_ptr->SetErrorStringWithFormat ("DW_OP_piece for offset %" PRIu64 " but top of stack is of size %" PRIu64,
2692                                                                          op_piece_offset,
2693                                                                          pieces.GetBuffer().GetByteSize());
2694                                 return false;
2695                             }
2696 
2697                             if (pieces.AppendDataToHostBuffer(curr_piece) == 0)
2698                             {
2699                                 if (error_ptr)
2700                                     error_ptr->SetErrorString("failed to append piece data");
2701                                 return false;
2702                             }
2703                         }
2704                         op_piece_offset += piece_byte_size;
2705                     }
2706                 }
2707             }
2708             break;
2709 
2710         case DW_OP_bit_piece:   // 0x9d ULEB128 bit size, ULEB128 bit offset (DWARF3);
2711             if (stack.size() < 1)
2712             {
2713                 if (error_ptr)
2714                     error_ptr->SetErrorString("Expression stack needs at least 1 item for DW_OP_bit_piece.");
2715                 return false;
2716             }
2717             else
2718             {
2719                 const uint64_t piece_bit_size = opcodes.GetULEB128(&offset);
2720                 const uint64_t piece_bit_offset = opcodes.GetULEB128(&offset);
2721                 switch (stack.back().GetValueType())
2722                 {
2723                 case Value::eValueTypeScalar:
2724                     {
2725                         if (!stack.back().GetScalar().ExtractBitfield (piece_bit_size, piece_bit_offset))
2726                         {
2727                             if (error_ptr)
2728                                 error_ptr->SetErrorStringWithFormat("unable to extract %" PRIu64 " bit value with %" PRIu64 " bit offset from a %" PRIu64 " bit scalar value.",
2729                                                                     piece_bit_size,
2730                                                                     piece_bit_offset,
2731                                                                     (uint64_t)(stack.back().GetScalar().GetByteSize()*8));
2732                             return false;
2733                         }
2734                     }
2735                     break;
2736 
2737                 case Value::eValueTypeFileAddress:
2738                 case Value::eValueTypeLoadAddress:
2739                 case Value::eValueTypeHostAddress:
2740                     if (error_ptr)
2741                     {
2742                         error_ptr->SetErrorStringWithFormat ("unable to extract DW_OP_bit_piece(bit_size = %" PRIu64 ", bit_offset = %" PRIu64 ") from an addresss value.",
2743                                                              piece_bit_size,
2744                                                              piece_bit_offset);
2745                     }
2746                     return false;
2747 
2748                 case Value::eValueTypeVector:
2749                     if (error_ptr)
2750                     {
2751                         error_ptr->SetErrorStringWithFormat ("unable to extract DW_OP_bit_piece(bit_size = %" PRIu64 ", bit_offset = %" PRIu64 ") from a vector value.",
2752                                                              piece_bit_size,
2753                                                              piece_bit_offset);
2754                     }
2755                     return false;
2756                 }
2757             }
2758             break;
2759 
2760         //----------------------------------------------------------------------
2761         // OPCODE: DW_OP_push_object_address
2762         // OPERANDS: none
2763         // DESCRIPTION: Pushes the address of the object currently being
2764         // evaluated as part of evaluation of a user presented expression.
2765         // This object may correspond to an independent variable described by
2766         // its own DIE or it may be a component of an array, structure, or class
2767         // whose address has been dynamically determined by an earlier step
2768         // during user expression evaluation.
2769         //----------------------------------------------------------------------
2770         case DW_OP_push_object_address:
2771             if (error_ptr)
2772                 error_ptr->SetErrorString ("Unimplemented opcode DW_OP_push_object_address.");
2773             return false;
2774 
2775         //----------------------------------------------------------------------
2776         // OPCODE: DW_OP_call2
2777         // OPERANDS:
2778         //      uint16_t compile unit relative offset of a DIE
2779         // DESCRIPTION: Performs subroutine calls during evaluation
2780         // of a DWARF expression. The operand is the 2-byte unsigned offset
2781         // of a debugging information entry in the current compilation unit.
2782         //
2783         // Operand interpretation is exactly like that for DW_FORM_ref2.
2784         //
2785         // This operation transfers control of DWARF expression evaluation
2786         // to the DW_AT_location attribute of the referenced DIE. If there is
2787         // no such attribute, then there is no effect. Execution of the DWARF
2788         // expression of a DW_AT_location attribute may add to and/or remove from
2789         // values on the stack. Execution returns to the point following the call
2790         // when the end of the attribute is reached. Values on the stack at the
2791         // time of the call may be used as parameters by the called expression
2792         // and values left on the stack by the called expression may be used as
2793         // return values by prior agreement between the calling and called
2794         // expressions.
2795         //----------------------------------------------------------------------
2796         case DW_OP_call2:
2797             if (error_ptr)
2798                 error_ptr->SetErrorString ("Unimplemented opcode DW_OP_call2.");
2799             return false;
2800         //----------------------------------------------------------------------
2801         // OPCODE: DW_OP_call4
2802         // OPERANDS: 1
2803         //      uint32_t compile unit relative offset of a DIE
2804         // DESCRIPTION: Performs a subroutine call during evaluation of a DWARF
2805         // expression. For DW_OP_call4, the operand is a 4-byte unsigned offset
2806         // of a debugging information entry in  the current compilation unit.
2807         //
2808         // Operand interpretation DW_OP_call4 is exactly like that for
2809         // DW_FORM_ref4.
2810         //
2811         // This operation transfers control of DWARF expression evaluation
2812         // to the DW_AT_location attribute of the referenced DIE. If there is
2813         // no such attribute, then there is no effect. Execution of the DWARF
2814         // expression of a DW_AT_location attribute may add to and/or remove from
2815         // values on the stack. Execution returns to the point following the call
2816         // when the end of the attribute is reached. Values on the stack at the
2817         // time of the call may be used as parameters by the called expression
2818         // and values left on the stack by the called expression may be used as
2819         // return values by prior agreement between the calling and called
2820         // expressions.
2821         //----------------------------------------------------------------------
2822         case DW_OP_call4:
2823             if (error_ptr)
2824                 error_ptr->SetErrorString ("Unimplemented opcode DW_OP_call4.");
2825             return false;
2826 
2827         //----------------------------------------------------------------------
2828         // OPCODE: DW_OP_stack_value
2829         // OPERANDS: None
2830         // DESCRIPTION: Specifies that the object does not exist in memory but
2831         // rather is a constant value.  The value from the top of the stack is
2832         // the value to be used.  This is the actual object value and not the
2833         // location.
2834         //----------------------------------------------------------------------
2835         case DW_OP_stack_value:
2836             stack.back().SetValueType(Value::eValueTypeScalar);
2837             break;
2838 
2839         //----------------------------------------------------------------------
2840         // OPCODE: DW_OP_call_frame_cfa
2841         // OPERANDS: None
2842         // DESCRIPTION: Specifies a DWARF expression that pushes the value of
2843         // the canonical frame address consistent with the call frame information
2844         // located in .debug_frame (or in the FDEs of the eh_frame section).
2845         //----------------------------------------------------------------------
2846         case DW_OP_call_frame_cfa:
2847             if (frame)
2848             {
2849                 // Note that we don't have to parse FDEs because this DWARF expression
2850                 // is commonly evaluated with a valid stack frame.
2851                 StackID id = frame->GetStackID();
2852                 addr_t cfa = id.GetCallFrameAddress();
2853                 if (cfa != LLDB_INVALID_ADDRESS)
2854                 {
2855                     stack.push_back(Scalar(cfa));
2856                     stack.back().SetValueType (Value::eValueTypeHostAddress);
2857                 }
2858                 else
2859                     if (error_ptr)
2860                         error_ptr->SetErrorString ("Stack frame does not include a canonical frame address for DW_OP_call_frame_cfa opcode.");
2861             }
2862             else
2863             {
2864                 if (error_ptr)
2865                     error_ptr->SetErrorString ("Invalid stack frame in context for DW_OP_call_frame_cfa opcode.");
2866                 return false;
2867             }
2868             break;
2869 
2870         //----------------------------------------------------------------------
2871         // OPCODE: DW_OP_GNU_push_tls_address
2872         // OPERANDS: none
2873         // DESCRIPTION: Pops a TLS offset from the stack, converts it to
2874         // an absolute value, and pushes it back on.
2875         //----------------------------------------------------------------------
2876         case DW_OP_GNU_push_tls_address:
2877             {
2878                 if (stack.size() < 1)
2879                 {
2880                     if (error_ptr)
2881                         error_ptr->SetErrorString("DW_OP_GNU_push_tls_address needs an argument.");
2882                     return false;
2883                 }
2884 
2885                 if (!exe_ctx || !opcode_ctx)
2886                 {
2887                     if (error_ptr)
2888                         error_ptr->SetErrorString("No context to evaluate TLS within.");
2889                     return false;
2890                 }
2891 
2892                 Thread *thread = exe_ctx->GetThreadPtr();
2893                 if (!thread)
2894                 {
2895                     if (error_ptr)
2896                         error_ptr->SetErrorString("No thread to evaluate TLS within.");
2897                     return false;
2898                 }
2899 
2900                 // Lookup the TLS block address for this thread and module.
2901                 addr_t tls_addr = thread->GetThreadLocalData (opcode_ctx);
2902 
2903                 if (tls_addr == LLDB_INVALID_ADDRESS)
2904                 {
2905                     if (error_ptr)
2906                         error_ptr->SetErrorString ("No TLS data currently exists for this thread.");
2907                     return false;
2908                 }
2909 
2910                 // Convert the TLS offset into the absolute address.
2911                 Scalar tmp = stack.back().ResolveValue(exe_ctx);
2912                 stack.back() = tmp + tls_addr;
2913                 stack.back().SetValueType (Value::eValueTypeLoadAddress);
2914             }
2915             break;
2916 
2917         default:
2918             if (log)
2919                 log->Printf("Unhandled opcode %s in DWARFExpression.", DW_OP_value_to_name(op));
2920             break;
2921         }
2922     }
2923 
2924     if (stack.empty())
2925     {
2926         // Nothing on the stack, check if we created a piece value from DW_OP_piece or DW_OP_bit_piece opcodes
2927         if (pieces.GetBuffer().GetByteSize())
2928         {
2929             result = pieces;
2930         }
2931         else
2932         {
2933             if (error_ptr)
2934                 error_ptr->SetErrorString ("Stack empty after evaluation.");
2935             return false;
2936         }
2937     }
2938     else
2939     {
2940         if (log && log->GetVerbose())
2941         {
2942             size_t count = stack.size();
2943             log->Printf("Stack after operation has %" PRIu64 " values:", (uint64_t)count);
2944             for (size_t i=0; i<count; ++i)
2945             {
2946                 StreamString new_value;
2947                 new_value.Printf("[%" PRIu64 "]", (uint64_t)i);
2948                 stack[i].Dump(&new_value);
2949                 log->Printf("  %s", new_value.GetData());
2950             }
2951         }
2952         result = stack.back();
2953     }
2954     return true;    // Return true on success
2955 }
2956 
2957