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DwarfParser.hpp revision 1.5.4.2
      1  1.5.4.2  yamt //===--------------------------- DwarfParser.hpp --------------------------===//
      2  1.5.4.2  yamt //
      3  1.5.4.2  yamt //                     The LLVM Compiler Infrastructure
      4  1.5.4.2  yamt //
      5  1.5.4.2  yamt // This file is dual licensed under the MIT and the University of Illinois Open
      6  1.5.4.2  yamt // Source Licenses. See LICENSE.TXT for details.
      7  1.5.4.2  yamt //
      8  1.5.4.2  yamt //
      9  1.5.4.2  yamt //  Parses DWARF CFIs (FDEs and CIEs).
     10  1.5.4.2  yamt //
     11  1.5.4.2  yamt //===----------------------------------------------------------------------===//
     12  1.5.4.2  yamt 
     13  1.5.4.2  yamt #ifndef __DWARF_PARSER_HPP__
     14  1.5.4.2  yamt #define __DWARF_PARSER_HPP__
     15  1.5.4.2  yamt 
     16  1.5.4.2  yamt #include <cstdint>
     17  1.5.4.2  yamt #include <cstdlib>
     18  1.5.4.2  yamt 
     19  1.5.4.2  yamt #include "dwarf2.h"
     20  1.5.4.2  yamt #include "AddressSpace.hpp"
     21  1.5.4.2  yamt 
     22  1.5.4.2  yamt namespace _Unwind {
     23  1.5.4.2  yamt 
     24  1.5.4.2  yamt /// CFI_Parser does basic parsing of a CFI (Call Frame Information) records.
     25  1.5.4.2  yamt /// See Dwarf Spec for details:
     26  1.5.4.2  yamt ///    http://refspecs.linuxbase.org/LSB_3.1.0/LSB-Core-generic/LSB-Core-generic/ehframechpt.html
     27  1.5.4.2  yamt ///
     28  1.5.4.2  yamt template <typename A, typename R> class CFI_Parser {
     29  1.5.4.2  yamt public:
     30  1.5.4.2  yamt   typedef typename A::pint_t pint_t;
     31  1.5.4.2  yamt 
     32  1.5.4.2  yamt   /// Information encoded in a CIE (Common Information Entry)
     33  1.5.4.2  yamt   struct CIE_Info {
     34  1.5.4.2  yamt     pint_t cieStart;
     35  1.5.4.2  yamt     pint_t cieLength;
     36  1.5.4.2  yamt     pint_t cieInstructions;
     37  1.5.4.2  yamt     pint_t personality;
     38  1.5.4.2  yamt     uint32_t codeAlignFactor;
     39  1.5.4.2  yamt     int dataAlignFactor;
     40  1.5.4.2  yamt     uint8_t pointerEncoding;
     41  1.5.4.2  yamt     uint8_t lsdaEncoding;
     42  1.5.4.2  yamt     uint8_t personalityEncoding;
     43  1.5.4.2  yamt     uint8_t personalityOffsetInCIE;
     44  1.5.4.2  yamt     bool isSignalFrame;
     45  1.5.4.2  yamt     bool fdesHaveAugmentationData;
     46  1.5.4.2  yamt     uint8_t returnAddressRegister;
     47  1.5.4.2  yamt   };
     48  1.5.4.2  yamt 
     49  1.5.4.2  yamt   /// Information about an FDE (Frame Description Entry)
     50  1.5.4.2  yamt   struct FDE_Info {
     51  1.5.4.2  yamt     pint_t fdeStart;
     52  1.5.4.2  yamt     pint_t fdeLength;
     53  1.5.4.2  yamt     pint_t fdeInstructions;
     54  1.5.4.2  yamt     pint_t pcStart;
     55  1.5.4.2  yamt     pint_t pcEnd;
     56  1.5.4.2  yamt     pint_t lsda;
     57  1.5.4.2  yamt   };
     58  1.5.4.2  yamt 
     59  1.5.4.2  yamt   /// Information about a frame layout and registers saved determined
     60  1.5.4.2  yamt   /// by "running" the DWARF FDE "instructions"
     61  1.5.4.2  yamt   enum {
     62  1.5.4.2  yamt     kMaxRegisterNumber = R::LAST_REGISTER + 1
     63  1.5.4.2  yamt   };
     64  1.5.4.2  yamt   enum RegisterSavedWhere {
     65  1.5.4.2  yamt     kRegisterUnused,
     66  1.5.4.2  yamt     kRegisterInCFA,
     67  1.5.4.2  yamt     kRegisterOffsetFromCFA,
     68  1.5.4.2  yamt     kRegisterInRegister,
     69  1.5.4.2  yamt     kRegisterAtExpression,
     70  1.5.4.2  yamt     kRegisterIsExpression,
     71  1.5.4.2  yamt   };
     72  1.5.4.2  yamt   struct RegisterLocation {
     73  1.5.4.2  yamt     RegisterSavedWhere location;
     74  1.5.4.2  yamt     int64_t value;
     75  1.5.4.2  yamt   };
     76  1.5.4.2  yamt   struct PrologInfo {
     77  1.5.4.2  yamt     uint32_t cfaRegister;
     78  1.5.4.2  yamt     int32_t cfaRegisterOffset; // CFA = (cfaRegister)+cfaRegisterOffset
     79  1.5.4.2  yamt     int64_t cfaExpression;     // CFA = expression
     80  1.5.4.2  yamt     uint32_t spExtraArgSize;
     81  1.5.4.2  yamt     uint32_t codeOffsetAtStackDecrement;
     82  1.5.4.2  yamt     RegisterLocation savedRegisters[kMaxRegisterNumber];
     83  1.5.4.2  yamt   };
     84  1.5.4.2  yamt 
     85  1.5.4.2  yamt   struct PrologInfoStackEntry {
     86  1.5.4.2  yamt     PrologInfoStackEntry(PrologInfoStackEntry *n, const PrologInfo &i)
     87  1.5.4.2  yamt         : next(n), info(i) {}
     88  1.5.4.2  yamt     PrologInfoStackEntry *next;
     89  1.5.4.2  yamt     PrologInfo info;
     90  1.5.4.2  yamt   };
     91  1.5.4.2  yamt 
     92  1.5.4.2  yamt   static void findPCRange(A &, pint_t, pint_t &, pint_t &);
     93  1.5.4.2  yamt 
     94  1.5.4.2  yamt   static bool decodeFDE(A &, pint_t, FDE_Info *, CIE_Info *,
     95  1.5.4.2  yamt                         unw_proc_info_t *ctx);
     96  1.5.4.2  yamt   static bool parseFDEInstructions(A &, const FDE_Info &, const CIE_Info &,
     97  1.5.4.2  yamt                                    pint_t, PrologInfo *, unw_proc_info_t *ctx);
     98  1.5.4.2  yamt 
     99  1.5.4.2  yamt   static bool parseCIE(A &, pint_t, CIE_Info *);
    100  1.5.4.2  yamt 
    101  1.5.4.2  yamt private:
    102  1.5.4.2  yamt   static bool parseInstructions(A &, pint_t, pint_t, const CIE_Info &, pint_t,
    103  1.5.4.2  yamt                                 PrologInfoStackEntry *&, PrologInfo *,
    104  1.5.4.2  yamt                                 unw_proc_info_t *ctx);
    105  1.5.4.2  yamt };
    106  1.5.4.2  yamt 
    107  1.5.4.2  yamt ///
    108  1.5.4.2  yamt /// Parse a FDE and return the last PC it covers.
    109  1.5.4.2  yamt ///
    110  1.5.4.2  yamt template <typename A, typename R>
    111  1.5.4.2  yamt void CFI_Parser<A, R>::findPCRange(A &addressSpace, pint_t fde, pint_t &pcStart,
    112  1.5.4.2  yamt                                    pint_t &pcEnd) {
    113  1.5.4.2  yamt   pcStart = 0;
    114  1.5.4.2  yamt   pcEnd = 0;
    115  1.5.4.2  yamt   pint_t p = fde;
    116  1.5.4.2  yamt   uint64_t cfiLength = addressSpace.get32(p);
    117  1.5.4.2  yamt   p += 4;
    118  1.5.4.2  yamt   if (cfiLength == 0xffffffff) {
    119  1.5.4.2  yamt     // 0xffffffff means length is really the next 8 Bytes.
    120  1.5.4.2  yamt     cfiLength = addressSpace.get64(p);
    121  1.5.4.2  yamt     p += 8;
    122  1.5.4.2  yamt   }
    123  1.5.4.2  yamt   if (cfiLength == 0)
    124  1.5.4.2  yamt     return;
    125  1.5.4.2  yamt   uint32_t ciePointer = addressSpace.get32(p);
    126  1.5.4.2  yamt   if (ciePointer == 0)
    127  1.5.4.2  yamt     return;
    128  1.5.4.2  yamt   pint_t nextCFI = p + cfiLength;
    129  1.5.4.2  yamt   pint_t cieStart = p - ciePointer;
    130  1.5.4.2  yamt   typename CFI_Parser<A, R>::CIE_Info cieInfo;
    131  1.5.4.2  yamt   if (!parseCIE(addressSpace, cieStart, &cieInfo))
    132  1.5.4.2  yamt     return;
    133  1.5.4.2  yamt   p += 4;
    134  1.5.4.2  yamt   // Parse pc begin and range.
    135  1.5.4.2  yamt   pcStart = addressSpace.getEncodedP(p, nextCFI, cieInfo.pointerEncoding, NULL);
    136  1.5.4.2  yamt   pcEnd = pcStart + addressSpace.getEncodedP(
    137  1.5.4.2  yamt                         p, nextCFI, cieInfo.pointerEncoding & 0x0F, NULL);
    138  1.5.4.2  yamt }
    139  1.5.4.2  yamt 
    140  1.5.4.2  yamt ///
    141  1.5.4.2  yamt /// Parse a FDE into a CIE_Info and an FDE_Info
    142  1.5.4.2  yamt ///
    143  1.5.4.2  yamt template <typename A, typename R>
    144  1.5.4.2  yamt bool CFI_Parser<A, R>::decodeFDE(A &addressSpace, pint_t fdeStart,
    145  1.5.4.2  yamt                                  FDE_Info *fdeInfo, CIE_Info *cieInfo,
    146  1.5.4.2  yamt                                  unw_proc_info_t *ctx) {
    147  1.5.4.2  yamt   pint_t p = fdeStart;
    148  1.5.4.2  yamt   uint64_t cfiLength = addressSpace.get32(p);
    149  1.5.4.2  yamt   p += 4;
    150  1.5.4.2  yamt   if (cfiLength == 0xffffffff) {
    151  1.5.4.2  yamt     // 0xffffffff means length is really the next 8 Bytes.
    152  1.5.4.2  yamt     cfiLength = addressSpace.get64(p);
    153  1.5.4.2  yamt     p += 8;
    154  1.5.4.2  yamt   }
    155  1.5.4.2  yamt   if (cfiLength == 0)
    156  1.5.4.2  yamt     return false;
    157  1.5.4.2  yamt   uint32_t ciePointer = addressSpace.get32(p);
    158  1.5.4.2  yamt   if (ciePointer == 0)
    159  1.5.4.2  yamt     return false;
    160  1.5.4.2  yamt   pint_t nextCFI = p + cfiLength;
    161  1.5.4.2  yamt   pint_t cieStart = p - ciePointer;
    162  1.5.4.2  yamt   if (!parseCIE(addressSpace, cieStart, cieInfo))
    163  1.5.4.2  yamt     return false;
    164  1.5.4.2  yamt   p += 4;
    165  1.5.4.2  yamt   // Parse pc begin and range.
    166  1.5.4.2  yamt   pint_t pcStart =
    167  1.5.4.2  yamt       addressSpace.getEncodedP(p, nextCFI, cieInfo->pointerEncoding, ctx);
    168  1.5.4.2  yamt   pint_t pcRange = addressSpace.getEncodedP(
    169  1.5.4.2  yamt       p, nextCFI, cieInfo->pointerEncoding & 0x0F, ctx);
    170  1.5.4.2  yamt   // Parse rest of info.
    171  1.5.4.2  yamt   fdeInfo->lsda = 0;
    172  1.5.4.2  yamt   // Check for augmentation length
    173  1.5.4.2  yamt   if (cieInfo->fdesHaveAugmentationData) {
    174  1.5.4.2  yamt     uintptr_t augLen = addressSpace.getULEB128(p, nextCFI);
    175  1.5.4.2  yamt     pint_t endOfAug = p + augLen;
    176  1.5.4.2  yamt     if (cieInfo->lsdaEncoding != DW_EH_PE_omit) {
    177  1.5.4.2  yamt       // Peek at value (without indirection).  Zero means no LSDA.
    178  1.5.4.2  yamt       pint_t lsdaStart = p;
    179  1.5.4.2  yamt       if (addressSpace.getEncodedP(p, nextCFI, cieInfo->lsdaEncoding & 0x0F,
    180  1.5.4.2  yamt                                    ctx) != 0) {
    181  1.5.4.2  yamt         // Reset pointer and re-parse LSDA address.
    182  1.5.4.2  yamt         p = lsdaStart;
    183  1.5.4.2  yamt         fdeInfo->lsda =
    184  1.5.4.2  yamt             addressSpace.getEncodedP(p, nextCFI, cieInfo->lsdaEncoding, ctx);
    185  1.5.4.2  yamt       }
    186  1.5.4.2  yamt     }
    187  1.5.4.2  yamt     p = endOfAug;
    188  1.5.4.2  yamt   }
    189  1.5.4.2  yamt   fdeInfo->fdeStart = fdeStart;
    190  1.5.4.2  yamt   fdeInfo->fdeLength = nextCFI - fdeStart;
    191  1.5.4.2  yamt   fdeInfo->fdeInstructions = p;
    192  1.5.4.2  yamt   fdeInfo->pcStart = pcStart;
    193  1.5.4.2  yamt   fdeInfo->pcEnd = pcStart + pcRange;
    194  1.5.4.2  yamt   return true;
    195  1.5.4.2  yamt }
    196  1.5.4.2  yamt 
    197  1.5.4.2  yamt /// Extract info from a CIE
    198  1.5.4.2  yamt template <typename A, typename R>
    199  1.5.4.2  yamt bool CFI_Parser<A, R>::parseCIE(A &addressSpace, pint_t cie,
    200  1.5.4.2  yamt                                 CIE_Info *cieInfo) {
    201  1.5.4.2  yamt   cieInfo->pointerEncoding = 0;
    202  1.5.4.2  yamt   cieInfo->lsdaEncoding = DW_EH_PE_omit;
    203  1.5.4.2  yamt   cieInfo->personalityEncoding = 0;
    204  1.5.4.2  yamt   cieInfo->personalityOffsetInCIE = 0;
    205  1.5.4.2  yamt   cieInfo->personality = 0;
    206  1.5.4.2  yamt   cieInfo->codeAlignFactor = 0;
    207  1.5.4.2  yamt   cieInfo->dataAlignFactor = 0;
    208  1.5.4.2  yamt   cieInfo->isSignalFrame = false;
    209  1.5.4.2  yamt   cieInfo->fdesHaveAugmentationData = false;
    210  1.5.4.2  yamt   cieInfo->cieStart = cie;
    211  1.5.4.2  yamt   pint_t p = cie;
    212  1.5.4.2  yamt   uint64_t cieLength = addressSpace.get32(p);
    213  1.5.4.2  yamt   p += 4;
    214  1.5.4.2  yamt   pint_t cieContentEnd = p + cieLength;
    215  1.5.4.2  yamt   if (cieLength == 0xffffffff) {
    216  1.5.4.2  yamt     // 0xffffffff means length is really the next 8 Bytes.
    217  1.5.4.2  yamt     cieLength = addressSpace.get64(p);
    218  1.5.4.2  yamt     p += 8;
    219  1.5.4.2  yamt     cieContentEnd = p + cieLength;
    220  1.5.4.2  yamt   }
    221  1.5.4.2  yamt   if (cieLength == 0)
    222  1.5.4.2  yamt     return true;
    223  1.5.4.2  yamt   // CIE ID is always 0
    224  1.5.4.2  yamt   if (addressSpace.get32(p) != 0)
    225  1.5.4.2  yamt     return false;
    226  1.5.4.2  yamt   p += 4;
    227  1.5.4.2  yamt   // Version is always 1 or 3
    228  1.5.4.2  yamt   uint8_t version = addressSpace.get8(p);
    229  1.5.4.2  yamt   if (version != 1 && version != 3)
    230  1.5.4.2  yamt     return false;
    231  1.5.4.2  yamt   ++p;
    232  1.5.4.2  yamt   // Save start of augmentation string and find end.
    233  1.5.4.2  yamt   pint_t strStart = p;
    234  1.5.4.2  yamt   while (addressSpace.get8(p) != 0)
    235  1.5.4.2  yamt     ++p;
    236  1.5.4.2  yamt   ++p;
    237  1.5.4.2  yamt   // Parse code aligment factor
    238  1.5.4.2  yamt   cieInfo->codeAlignFactor = addressSpace.getULEB128(p, cieContentEnd);
    239  1.5.4.2  yamt   // Parse data alignment factor
    240  1.5.4.2  yamt   cieInfo->dataAlignFactor = addressSpace.getSLEB128(p, cieContentEnd);
    241  1.5.4.2  yamt   // Parse return address register
    242  1.5.4.2  yamt   cieInfo->returnAddressRegister = (uint8_t)addressSpace.getULEB128(p, cieContentEnd);
    243  1.5.4.2  yamt   // Parse augmentation data based on augmentation string.
    244  1.5.4.2  yamt   if (addressSpace.get8(strStart) == 'z') {
    245  1.5.4.2  yamt     // parse augmentation data length
    246  1.5.4.2  yamt     addressSpace.getULEB128(p, cieContentEnd);
    247  1.5.4.2  yamt     for (pint_t s = strStart; addressSpace.get8(s) != '\0'; ++s) {
    248  1.5.4.2  yamt       switch (addressSpace.get8(s)) {
    249  1.5.4.2  yamt       case 'z':
    250  1.5.4.2  yamt         cieInfo->fdesHaveAugmentationData = true;
    251  1.5.4.2  yamt         break;
    252  1.5.4.2  yamt       case 'P':
    253  1.5.4.2  yamt         cieInfo->personalityEncoding = addressSpace.get8(p);
    254  1.5.4.2  yamt         ++p;
    255  1.5.4.2  yamt         cieInfo->personalityOffsetInCIE = p - cie;
    256  1.5.4.2  yamt         cieInfo->personality = addressSpace.getEncodedP(
    257  1.5.4.2  yamt             p, cieContentEnd, cieInfo->personalityEncoding, NULL);
    258  1.5.4.2  yamt         break;
    259  1.5.4.2  yamt       case 'L':
    260  1.5.4.2  yamt         cieInfo->lsdaEncoding = addressSpace.get8(p);
    261  1.5.4.2  yamt         ++p;
    262  1.5.4.2  yamt         break;
    263  1.5.4.2  yamt       case 'R':
    264  1.5.4.2  yamt         cieInfo->pointerEncoding = addressSpace.get8(p);
    265  1.5.4.2  yamt         ++p;
    266  1.5.4.2  yamt         break;
    267  1.5.4.2  yamt       case 'S':
    268  1.5.4.2  yamt         cieInfo->isSignalFrame = true;
    269  1.5.4.2  yamt         break;
    270  1.5.4.2  yamt       default:
    271  1.5.4.2  yamt         // ignore unknown letters
    272  1.5.4.2  yamt         break;
    273  1.5.4.2  yamt       }
    274  1.5.4.2  yamt     }
    275  1.5.4.2  yamt   }
    276  1.5.4.2  yamt   cieInfo->cieLength = cieContentEnd - cieInfo->cieStart;
    277  1.5.4.2  yamt   cieInfo->cieInstructions = p;
    278  1.5.4.2  yamt   return true;
    279  1.5.4.2  yamt }
    280  1.5.4.2  yamt 
    281  1.5.4.2  yamt /// "Run" the dwarf instructions and create the abstact PrologInfo for an FDE.
    282  1.5.4.2  yamt template <typename A, typename R>
    283  1.5.4.2  yamt bool CFI_Parser<A, R>::parseFDEInstructions(A &addressSpace,
    284  1.5.4.2  yamt                                             const FDE_Info &fdeInfo,
    285  1.5.4.2  yamt                                             const CIE_Info &cieInfo,
    286  1.5.4.2  yamt                                             pint_t upToPC, PrologInfo *results,
    287  1.5.4.2  yamt                                             unw_proc_info_t *ctx) {
    288  1.5.4.2  yamt   // Clear results.
    289  1.5.4.2  yamt   memset(results, 0, sizeof(*results));
    290  1.5.4.2  yamt   PrologInfoStackEntry *rememberStack = NULL;
    291  1.5.4.2  yamt 
    292  1.5.4.2  yamt   // First parse the CIE then FDE instructions.
    293  1.5.4.2  yamt   if (!parseInstructions(addressSpace, cieInfo.cieInstructions,
    294  1.5.4.2  yamt                          cieInfo.cieStart + cieInfo.cieLength, cieInfo,
    295  1.5.4.2  yamt                          (pint_t)(-1), rememberStack, results, ctx))
    296  1.5.4.2  yamt     return false;
    297  1.5.4.2  yamt   return parseInstructions(addressSpace, fdeInfo.fdeInstructions,
    298  1.5.4.2  yamt                            fdeInfo.fdeStart + fdeInfo.fdeLength, cieInfo,
    299  1.5.4.2  yamt                            upToPC - fdeInfo.pcStart, rememberStack, results,
    300  1.5.4.2  yamt                            ctx);
    301  1.5.4.2  yamt }
    302  1.5.4.2  yamt 
    303  1.5.4.2  yamt /// "Run" the DWARF instructions.
    304  1.5.4.2  yamt template <typename A, typename R>
    305  1.5.4.2  yamt bool
    306  1.5.4.2  yamt CFI_Parser<A, R>::parseInstructions(A &addressSpace, pint_t instructions,
    307  1.5.4.2  yamt                                     pint_t instructionsEnd,
    308  1.5.4.2  yamt                                     const CIE_Info &cieInfo, pint_t pcoffset,
    309  1.5.4.2  yamt                                     PrologInfoStackEntry *&rememberStack,
    310  1.5.4.2  yamt                                     PrologInfo *results, unw_proc_info_t *ctx) {
    311  1.5.4.2  yamt   pint_t p = instructions;
    312  1.5.4.2  yamt   uint32_t codeOffset = 0;
    313  1.5.4.2  yamt   PrologInfo initialState = *results;
    314  1.5.4.2  yamt 
    315  1.5.4.2  yamt   // See Dwarf Spec, section 6.4.2 for details on unwind opcodes.
    316  1.5.4.2  yamt   while (p < instructionsEnd && codeOffset < pcoffset) {
    317  1.5.4.2  yamt     uint64_t reg;
    318  1.5.4.2  yamt     uint64_t reg2;
    319  1.5.4.2  yamt     int64_t offset;
    320  1.5.4.2  yamt     uint64_t length;
    321  1.5.4.2  yamt     uint8_t opcode = addressSpace.get8(p);
    322  1.5.4.2  yamt     uint8_t operand;
    323  1.5.4.2  yamt     PrologInfoStackEntry *entry;
    324  1.5.4.2  yamt     ++p;
    325  1.5.4.2  yamt     switch (opcode) {
    326  1.5.4.2  yamt     case DW_CFA_nop:
    327  1.5.4.2  yamt       break;
    328  1.5.4.2  yamt     case DW_CFA_set_loc:
    329  1.5.4.2  yamt       codeOffset = addressSpace.getEncodedP(p, instructionsEnd,
    330  1.5.4.2  yamt                                             cieInfo.pointerEncoding, ctx);
    331  1.5.4.2  yamt       break;
    332  1.5.4.2  yamt     case DW_CFA_advance_loc1:
    333  1.5.4.2  yamt       codeOffset += (addressSpace.get8(p) * cieInfo.codeAlignFactor);
    334  1.5.4.2  yamt       p += 1;
    335  1.5.4.2  yamt       break;
    336  1.5.4.2  yamt     case DW_CFA_advance_loc2:
    337  1.5.4.2  yamt       codeOffset += (addressSpace.get16(p) * cieInfo.codeAlignFactor);
    338  1.5.4.2  yamt       p += 2;
    339  1.5.4.2  yamt       break;
    340  1.5.4.2  yamt     case DW_CFA_advance_loc4:
    341  1.5.4.2  yamt       codeOffset += (addressSpace.get32(p) * cieInfo.codeAlignFactor);
    342  1.5.4.2  yamt       p += 4;
    343  1.5.4.2  yamt       break;
    344  1.5.4.2  yamt     case DW_CFA_offset_extended:
    345  1.5.4.2  yamt       reg = R::dwarf2regno(addressSpace.getULEB128(p, instructionsEnd));
    346  1.5.4.2  yamt       offset =
    347  1.5.4.2  yamt           addressSpace.getULEB128(p, instructionsEnd) * cieInfo.dataAlignFactor;
    348  1.5.4.2  yamt       if (reg > kMaxRegisterNumber)
    349  1.5.4.2  yamt         return false;
    350  1.5.4.2  yamt       results->savedRegisters[reg].location = kRegisterInCFA;
    351  1.5.4.2  yamt       results->savedRegisters[reg].value = offset;
    352  1.5.4.2  yamt       break;
    353  1.5.4.2  yamt     case DW_CFA_restore_extended:
    354  1.5.4.2  yamt       reg = R::dwarf2regno(addressSpace.getULEB128(p, instructionsEnd));
    355  1.5.4.2  yamt       if (reg > kMaxRegisterNumber)
    356  1.5.4.2  yamt         return false;
    357  1.5.4.2  yamt       results->savedRegisters[reg] = initialState.savedRegisters[reg];
    358  1.5.4.2  yamt       break;
    359  1.5.4.2  yamt     case DW_CFA_undefined:
    360  1.5.4.2  yamt       reg = R::dwarf2regno(addressSpace.getULEB128(p, instructionsEnd));
    361  1.5.4.2  yamt       if (reg > kMaxRegisterNumber)
    362  1.5.4.2  yamt         return false;
    363  1.5.4.2  yamt       results->savedRegisters[reg].location = kRegisterUnused;
    364  1.5.4.2  yamt       break;
    365  1.5.4.2  yamt     case DW_CFA_same_value:
    366  1.5.4.2  yamt       reg = R::dwarf2regno(addressSpace.getULEB128(p, instructionsEnd));
    367  1.5.4.2  yamt       if (reg > kMaxRegisterNumber)
    368  1.5.4.2  yamt         return false;
    369  1.5.4.2  yamt       // "same value" means register was stored in frame, but its current
    370  1.5.4.2  yamt       // value has not changed, so no need to restore from frame.
    371  1.5.4.2  yamt       // We model this as if the register was never saved.
    372  1.5.4.2  yamt       results->savedRegisters[reg].location = kRegisterUnused;
    373  1.5.4.2  yamt       break;
    374  1.5.4.2  yamt     case DW_CFA_register:
    375  1.5.4.2  yamt       reg = R::dwarf2regno(addressSpace.getULEB128(p, instructionsEnd));
    376  1.5.4.2  yamt       reg2 = R::dwarf2regno(addressSpace.getULEB128(p, instructionsEnd));
    377  1.5.4.2  yamt       if (reg > kMaxRegisterNumber)
    378  1.5.4.2  yamt         return false;
    379  1.5.4.2  yamt       if (reg2 > kMaxRegisterNumber)
    380  1.5.4.2  yamt         return false;
    381  1.5.4.2  yamt       results->savedRegisters[reg].location = kRegisterInRegister;
    382  1.5.4.2  yamt       results->savedRegisters[reg].value = reg2;
    383  1.5.4.2  yamt       break;
    384  1.5.4.2  yamt     case DW_CFA_remember_state:
    385  1.5.4.2  yamt       // avoid operator new, because that would be an upward dependency
    386  1.5.4.2  yamt       entry = (PrologInfoStackEntry *)malloc(sizeof(PrologInfoStackEntry));
    387  1.5.4.2  yamt       if (entry == NULL)
    388  1.5.4.2  yamt         return false;
    389  1.5.4.2  yamt 
    390  1.5.4.2  yamt       entry->next = rememberStack;
    391  1.5.4.2  yamt       entry->info = *results;
    392  1.5.4.2  yamt       rememberStack = entry;
    393  1.5.4.2  yamt       break;
    394  1.5.4.2  yamt     case DW_CFA_restore_state:
    395  1.5.4.2  yamt       if (rememberStack == NULL)
    396  1.5.4.2  yamt         return false;
    397  1.5.4.2  yamt       {
    398  1.5.4.2  yamt         PrologInfoStackEntry *top = rememberStack;
    399  1.5.4.2  yamt         *results = top->info;
    400  1.5.4.2  yamt         rememberStack = top->next;
    401  1.5.4.2  yamt         free((char *)top);
    402  1.5.4.2  yamt       }
    403  1.5.4.2  yamt       break;
    404  1.5.4.2  yamt     case DW_CFA_def_cfa:
    405  1.5.4.2  yamt       reg = R::dwarf2regno(addressSpace.getULEB128(p, instructionsEnd));
    406  1.5.4.2  yamt       offset = addressSpace.getULEB128(p, instructionsEnd);
    407  1.5.4.2  yamt       if (reg > kMaxRegisterNumber)
    408  1.5.4.2  yamt         return false;
    409  1.5.4.2  yamt       results->cfaRegister = reg;
    410  1.5.4.2  yamt       results->cfaRegisterOffset = offset;
    411  1.5.4.2  yamt       break;
    412  1.5.4.2  yamt     case DW_CFA_def_cfa_register:
    413  1.5.4.2  yamt       reg = R::dwarf2regno(addressSpace.getULEB128(p, instructionsEnd));
    414  1.5.4.2  yamt       if (reg > kMaxRegisterNumber)
    415  1.5.4.2  yamt         return false;
    416  1.5.4.2  yamt       results->cfaRegister = reg;
    417  1.5.4.2  yamt       break;
    418  1.5.4.2  yamt     case DW_CFA_def_cfa_offset:
    419  1.5.4.2  yamt       results->cfaRegisterOffset = addressSpace.getULEB128(p, instructionsEnd);
    420  1.5.4.2  yamt       results->codeOffsetAtStackDecrement = codeOffset;
    421  1.5.4.2  yamt       break;
    422  1.5.4.2  yamt     case DW_CFA_def_cfa_expression:
    423  1.5.4.2  yamt       results->cfaRegister = 0;
    424  1.5.4.2  yamt       results->cfaExpression = p;
    425  1.5.4.2  yamt       length = addressSpace.getULEB128(p, instructionsEnd);
    426  1.5.4.2  yamt       p += length;
    427  1.5.4.2  yamt       break;
    428  1.5.4.2  yamt     case DW_CFA_expression:
    429  1.5.4.2  yamt       reg = R::dwarf2regno(addressSpace.getULEB128(p, instructionsEnd));
    430  1.5.4.2  yamt       if (reg > kMaxRegisterNumber)
    431  1.5.4.2  yamt         return false;
    432  1.5.4.2  yamt       results->savedRegisters[reg].location = kRegisterAtExpression;
    433  1.5.4.2  yamt       results->savedRegisters[reg].value = p;
    434  1.5.4.2  yamt       length = addressSpace.getULEB128(p, instructionsEnd);
    435  1.5.4.2  yamt       p += length;
    436  1.5.4.2  yamt       break;
    437  1.5.4.2  yamt     case DW_CFA_offset_extended_sf:
    438  1.5.4.2  yamt       reg = R::dwarf2regno(addressSpace.getULEB128(p, instructionsEnd));
    439  1.5.4.2  yamt       if (reg > kMaxRegisterNumber)
    440  1.5.4.2  yamt         return false;
    441  1.5.4.2  yamt       offset =
    442  1.5.4.2  yamt           addressSpace.getSLEB128(p, instructionsEnd) * cieInfo.dataAlignFactor;
    443  1.5.4.2  yamt       results->savedRegisters[reg].location = kRegisterInCFA;
    444  1.5.4.2  yamt       results->savedRegisters[reg].value = offset;
    445  1.5.4.2  yamt       break;
    446  1.5.4.2  yamt     case DW_CFA_def_cfa_sf:
    447  1.5.4.2  yamt       reg = R::dwarf2regno(addressSpace.getULEB128(p, instructionsEnd));
    448  1.5.4.2  yamt       offset =
    449  1.5.4.2  yamt           addressSpace.getSLEB128(p, instructionsEnd) * cieInfo.dataAlignFactor;
    450  1.5.4.2  yamt       if (reg > kMaxRegisterNumber)
    451  1.5.4.2  yamt         return false;
    452  1.5.4.2  yamt       results->cfaRegister = reg;
    453  1.5.4.2  yamt       results->cfaRegisterOffset = offset;
    454  1.5.4.2  yamt       break;
    455  1.5.4.2  yamt     case DW_CFA_def_cfa_offset_sf:
    456  1.5.4.2  yamt       results->cfaRegisterOffset =
    457  1.5.4.2  yamt           addressSpace.getSLEB128(p, instructionsEnd) * cieInfo.dataAlignFactor;
    458  1.5.4.2  yamt       results->codeOffsetAtStackDecrement = codeOffset;
    459  1.5.4.2  yamt       break;
    460  1.5.4.2  yamt     case DW_CFA_val_offset:
    461  1.5.4.2  yamt       reg = R::dwarf2regno(addressSpace.getULEB128(p, instructionsEnd));
    462  1.5.4.2  yamt       offset =
    463  1.5.4.2  yamt           addressSpace.getULEB128(p, instructionsEnd) * cieInfo.dataAlignFactor;
    464  1.5.4.2  yamt       if (reg > kMaxRegisterNumber)
    465  1.5.4.2  yamt         return false;
    466  1.5.4.2  yamt       results->savedRegisters[reg].location = kRegisterOffsetFromCFA;
    467  1.5.4.2  yamt       results->savedRegisters[reg].value = offset;
    468  1.5.4.2  yamt       break;
    469  1.5.4.2  yamt     case DW_CFA_val_offset_sf:
    470  1.5.4.2  yamt       reg = R::dwarf2regno(addressSpace.getULEB128(p, instructionsEnd));
    471  1.5.4.2  yamt       if (reg > kMaxRegisterNumber)
    472  1.5.4.2  yamt         return false;
    473  1.5.4.2  yamt       offset =
    474  1.5.4.2  yamt           addressSpace.getSLEB128(p, instructionsEnd) * cieInfo.dataAlignFactor;
    475  1.5.4.2  yamt       results->savedRegisters[reg].location = kRegisterOffsetFromCFA;
    476  1.5.4.2  yamt       results->savedRegisters[reg].value = offset;
    477  1.5.4.2  yamt       break;
    478  1.5.4.2  yamt     case DW_CFA_val_expression:
    479  1.5.4.2  yamt       reg = R::dwarf2regno(addressSpace.getULEB128(p, instructionsEnd));
    480  1.5.4.2  yamt       if (reg > kMaxRegisterNumber)
    481  1.5.4.2  yamt         return false;
    482  1.5.4.2  yamt       results->savedRegisters[reg].location = kRegisterIsExpression;
    483  1.5.4.2  yamt       results->savedRegisters[reg].value = p;
    484  1.5.4.2  yamt       length = addressSpace.getULEB128(p, instructionsEnd);
    485  1.5.4.2  yamt       p += length;
    486  1.5.4.2  yamt       break;
    487  1.5.4.2  yamt     case DW_CFA_GNU_window_save:
    488  1.5.4.2  yamt #if defined(__sparc__)
    489  1.5.4.2  yamt       for (reg = 8; reg < 16; ++reg) {
    490  1.5.4.2  yamt         results->savedRegisters[reg].location = kRegisterInRegister;
    491  1.5.4.2  yamt         results->savedRegisters[reg].value = reg + 16;
    492  1.5.4.2  yamt       }
    493  1.5.4.2  yamt       for (reg = 16; reg < 32; ++reg) {
    494  1.5.4.2  yamt         results->savedRegisters[reg].location = kRegisterInCFA;
    495  1.5.4.2  yamt         results->savedRegisters[reg].value = (reg - 16) * sizeof(typename R::reg_t);
    496  1.5.4.2  yamt       }
    497  1.5.4.2  yamt       break;
    498  1.5.4.2  yamt #else
    499  1.5.4.2  yamt       return false;
    500  1.5.4.2  yamt #endif
    501  1.5.4.2  yamt     case DW_CFA_GNU_args_size:
    502  1.5.4.2  yamt       offset = addressSpace.getULEB128(p, instructionsEnd);
    503  1.5.4.2  yamt       results->spExtraArgSize = offset;
    504  1.5.4.2  yamt       break;
    505  1.5.4.2  yamt     case DW_CFA_GNU_negative_offset_extended:
    506  1.5.4.2  yamt       reg = R::dwarf2regno(addressSpace.getULEB128(p, instructionsEnd));
    507  1.5.4.2  yamt       if (reg > kMaxRegisterNumber)
    508  1.5.4.2  yamt         return false;
    509  1.5.4.2  yamt       offset =
    510  1.5.4.2  yamt           addressSpace.getULEB128(p, instructionsEnd) * cieInfo.dataAlignFactor;
    511  1.5.4.2  yamt       results->savedRegisters[reg].location = kRegisterInCFA;
    512  1.5.4.2  yamt       results->savedRegisters[reg].value = -offset;
    513  1.5.4.2  yamt       break;
    514  1.5.4.2  yamt     default:
    515  1.5.4.2  yamt       operand = opcode & 0x3F;
    516  1.5.4.2  yamt       switch (opcode & 0xC0) {
    517  1.5.4.2  yamt       case DW_CFA_offset:
    518  1.5.4.2  yamt         reg = R::dwarf2regno(operand);
    519  1.5.4.2  yamt         if (reg > kMaxRegisterNumber)
    520  1.5.4.2  yamt           return false;
    521  1.5.4.2  yamt         offset = addressSpace.getULEB128(p, instructionsEnd) *
    522  1.5.4.2  yamt                  cieInfo.dataAlignFactor;
    523  1.5.4.2  yamt         results->savedRegisters[reg].location = kRegisterInCFA;
    524  1.5.4.2  yamt         results->savedRegisters[reg].value = offset;
    525  1.5.4.2  yamt         break;
    526  1.5.4.2  yamt       case DW_CFA_advance_loc:
    527  1.5.4.2  yamt         codeOffset += operand * cieInfo.codeAlignFactor;
    528  1.5.4.2  yamt         break;
    529  1.5.4.2  yamt       case DW_CFA_restore:
    530  1.5.4.2  yamt         reg = R::dwarf2regno(operand);
    531  1.5.4.2  yamt         if (reg > kMaxRegisterNumber)
    532  1.5.4.2  yamt           return false;
    533  1.5.4.2  yamt         results->savedRegisters[reg] = initialState.savedRegisters[reg];
    534  1.5.4.2  yamt         break;
    535  1.5.4.2  yamt       default:
    536  1.5.4.2  yamt         return false;
    537  1.5.4.2  yamt       }
    538  1.5.4.2  yamt     }
    539  1.5.4.2  yamt   }
    540  1.5.4.2  yamt 
    541  1.5.4.2  yamt   return true;
    542  1.5.4.2  yamt }
    543  1.5.4.2  yamt 
    544  1.5.4.2  yamt } // namespace _Unwind
    545  1.5.4.2  yamt 
    546  1.5.4.2  yamt #endif // __DWARF_PARSER_HPP__
    547