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-rw-r--r--src/DwarfParser.hpp722
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diff --git a/src/DwarfParser.hpp b/src/DwarfParser.hpp
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+//===--------------------------- DwarfParser.hpp --------------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//
+// Parses DWARF CFIs (FDEs and CIEs).
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef __DWARF_PARSER_HPP__
+#define __DWARF_PARSER_HPP__
+
+#include <inttypes.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "libunwind.h"
+#include "dwarf2.h"
+
+#include "AddressSpace.hpp"
+
+namespace libunwind {
+
+/// CFI_Parser does basic parsing of a CFI (Call Frame Information) records.
+/// See Dwarf Spec for details:
+/// http://refspecs.linuxbase.org/LSB_3.1.0/LSB-Core-generic/LSB-Core-generic/ehframechpt.html
+///
+template <typename A>
+class CFI_Parser {
+public:
+ typedef typename A::pint_t pint_t;
+
+ /// Information encoded in a CIE (Common Information Entry)
+ struct CIE_Info {
+ pint_t cieStart;
+ pint_t cieLength;
+ pint_t cieInstructions;
+ uint8_t pointerEncoding;
+ uint8_t lsdaEncoding;
+ uint8_t personalityEncoding;
+ uint8_t personalityOffsetInCIE;
+ pint_t personality;
+ uint32_t codeAlignFactor;
+ int dataAlignFactor;
+ bool isSignalFrame;
+ bool fdesHaveAugmentationData;
+ uint8_t returnAddressRegister;
+ };
+
+ /// Information about an FDE (Frame Description Entry)
+ struct FDE_Info {
+ pint_t fdeStart;
+ pint_t fdeLength;
+ pint_t fdeInstructions;
+ pint_t pcStart;
+ pint_t pcEnd;
+ pint_t lsda;
+ };
+
+ enum {
+ kMaxRegisterNumber = 120
+ };
+ enum RegisterSavedWhere {
+ kRegisterUnused,
+ kRegisterInCFA,
+ kRegisterOffsetFromCFA,
+ kRegisterInRegister,
+ kRegisterAtExpression,
+ kRegisterIsExpression
+ };
+ struct RegisterLocation {
+ RegisterSavedWhere location;
+ int64_t value;
+ };
+ /// Information about a frame layout and registers saved determined
+ /// by "running" the dwarf FDE "instructions"
+ struct PrologInfo {
+ uint32_t cfaRegister;
+ int32_t cfaRegisterOffset; // CFA = (cfaRegister)+cfaRegisterOffset
+ int64_t cfaExpression; // CFA = expression
+ uint32_t spExtraArgSize;
+ uint32_t codeOffsetAtStackDecrement;
+ bool registersInOtherRegisters;
+ bool sameValueUsed;
+ RegisterLocation savedRegisters[kMaxRegisterNumber];
+ };
+
+ struct PrologInfoStackEntry {
+ PrologInfoStackEntry(PrologInfoStackEntry *n, const PrologInfo &i)
+ : next(n), info(i) {}
+ PrologInfoStackEntry *next;
+ PrologInfo info;
+ };
+
+ static bool findFDE(A &addressSpace, pint_t pc, pint_t ehSectionStart,
+ uint32_t sectionLength, pint_t fdeHint, FDE_Info *fdeInfo,
+ CIE_Info *cieInfo);
+ static const char *decodeFDE(A &addressSpace, pint_t fdeStart,
+ FDE_Info *fdeInfo, CIE_Info *cieInfo);
+ static bool parseFDEInstructions(A &addressSpace, const FDE_Info &fdeInfo,
+ const CIE_Info &cieInfo, pint_t upToPC,
+ PrologInfo *results);
+
+ static const char *parseCIE(A &addressSpace, pint_t cie, CIE_Info *cieInfo);
+
+private:
+ static bool parseInstructions(A &addressSpace, pint_t instructions,
+ pint_t instructionsEnd, const CIE_Info &cieInfo,
+ pint_t pcoffset,
+ PrologInfoStackEntry *&rememberStack,
+ PrologInfo *results);
+};
+
+/// Parse a FDE into a CIE_Info and an FDE_Info
+template <typename A>
+const char *CFI_Parser<A>::decodeFDE(A &addressSpace, pint_t fdeStart,
+ FDE_Info *fdeInfo, CIE_Info *cieInfo) {
+ pint_t p = fdeStart;
+ pint_t cfiLength = (pint_t)addressSpace.get32(p);
+ p += 4;
+ if (cfiLength == 0xffffffff) {
+ // 0xffffffff means length is really next 8 bytes
+ cfiLength = (pint_t)addressSpace.get64(p);
+ p += 8;
+ }
+ if (cfiLength == 0)
+ return "FDE has zero length"; // end marker
+ uint32_t ciePointer = addressSpace.get32(p);
+ if (ciePointer == 0)
+ return "FDE is really a CIE"; // this is a CIE not an FDE
+ pint_t nextCFI = p + cfiLength;
+ pint_t cieStart = p - ciePointer;
+ const char *err = parseCIE(addressSpace, cieStart, cieInfo);
+ if (err != NULL)
+ return err;
+ p += 4;
+ // parse pc begin and range
+ pint_t pcStart =
+ addressSpace.getEncodedP(p, nextCFI, cieInfo->pointerEncoding);
+ pint_t pcRange =
+ addressSpace.getEncodedP(p, nextCFI, cieInfo->pointerEncoding & 0x0F);
+ // parse rest of info
+ fdeInfo->lsda = 0;
+ // check for augmentation length
+ if (cieInfo->fdesHaveAugmentationData) {
+ pint_t augLen = (pint_t)addressSpace.getULEB128(p, nextCFI);
+ pint_t endOfAug = p + augLen;
+ if (cieInfo->lsdaEncoding != DW_EH_PE_omit) {
+ // peek at value (without indirection). Zero means no lsda
+ pint_t lsdaStart = p;
+ if (addressSpace.getEncodedP(p, nextCFI, cieInfo->lsdaEncoding & 0x0F) !=
+ 0) {
+ // reset pointer and re-parse lsda address
+ p = lsdaStart;
+ fdeInfo->lsda =
+ addressSpace.getEncodedP(p, nextCFI, cieInfo->lsdaEncoding);
+ }
+ }
+ p = endOfAug;
+ }
+ fdeInfo->fdeStart = fdeStart;
+ fdeInfo->fdeLength = nextCFI - fdeStart;
+ fdeInfo->fdeInstructions = p;
+ fdeInfo->pcStart = pcStart;
+ fdeInfo->pcEnd = pcStart + pcRange;
+ return NULL; // success
+}
+
+/// Scan an eh_frame section to find an FDE for a pc
+template <typename A>
+bool CFI_Parser<A>::findFDE(A &addressSpace, pint_t pc, pint_t ehSectionStart,
+ uint32_t sectionLength, pint_t fdeHint,
+ FDE_Info *fdeInfo, CIE_Info *cieInfo) {
+ //fprintf(stderr, "findFDE(0x%llX)\n", (long long)pc);
+ pint_t p = (fdeHint != 0) ? fdeHint : ehSectionStart;
+ const pint_t ehSectionEnd = p + sectionLength;
+ while (p < ehSectionEnd) {
+ pint_t currentCFI = p;
+ //fprintf(stderr, "findFDE() CFI at 0x%llX\n", (long long)p);
+ pint_t cfiLength = addressSpace.get32(p);
+ p += 4;
+ if (cfiLength == 0xffffffff) {
+ // 0xffffffff means length is really next 8 bytes
+ cfiLength = (pint_t)addressSpace.get64(p);
+ p += 8;
+ }
+ if (cfiLength == 0)
+ return false; // end marker
+ uint32_t id = addressSpace.get32(p);
+ if (id == 0) {
+ // skip over CIEs
+ p += cfiLength;
+ } else {
+ // process FDE to see if it covers pc
+ pint_t nextCFI = p + cfiLength;
+ uint32_t ciePointer = addressSpace.get32(p);
+ pint_t cieStart = p - ciePointer;
+ // validate pointer to CIE is within section
+ if ((ehSectionStart <= cieStart) && (cieStart < ehSectionEnd)) {
+ if (parseCIE(addressSpace, cieStart, cieInfo) == NULL) {
+ p += 4;
+ // parse pc begin and range
+ pint_t pcStart =
+ addressSpace.getEncodedP(p, nextCFI, cieInfo->pointerEncoding);
+ pint_t pcRange = addressSpace.getEncodedP(
+ p, nextCFI, cieInfo->pointerEncoding & 0x0F);
+ // test if pc is within the function this FDE covers
+ if ((pcStart < pc) && (pc <= pcStart + pcRange)) {
+ // parse rest of info
+ fdeInfo->lsda = 0;
+ // check for augmentation length
+ if (cieInfo->fdesHaveAugmentationData) {
+ pint_t augLen = (pint_t)addressSpace.getULEB128(p, nextCFI);
+ pint_t endOfAug = p + augLen;
+ if (cieInfo->lsdaEncoding != DW_EH_PE_omit) {
+ // peek at value (without indirection). Zero means no lsda
+ pint_t lsdaStart = p;
+ if (addressSpace.getEncodedP(
+ p, nextCFI, cieInfo->lsdaEncoding & 0x0F) != 0) {
+ // reset pointer and re-parse lsda address
+ p = lsdaStart;
+ fdeInfo->lsda = addressSpace
+ .getEncodedP(p, nextCFI, cieInfo->lsdaEncoding);
+ }
+ }
+ p = endOfAug;
+ }
+ fdeInfo->fdeStart = currentCFI;
+ fdeInfo->fdeLength = nextCFI - currentCFI;
+ fdeInfo->fdeInstructions = p;
+ fdeInfo->pcStart = pcStart;
+ fdeInfo->pcEnd = pcStart + pcRange;
+ return true;
+ } else {
+ // pc is not in begin/range, skip this FDE
+ }
+ } else {
+ // malformed CIE, now augmentation describing pc range encoding
+ }
+ } else {
+ // malformed FDE. CIE is bad
+ }
+ p = nextCFI;
+ }
+ }
+ return false;
+}
+
+/// Extract info from a CIE
+template <typename A>
+const char *CFI_Parser<A>::parseCIE(A &addressSpace, pint_t cie,
+ CIE_Info *cieInfo) {
+ cieInfo->pointerEncoding = 0;
+ cieInfo->lsdaEncoding = DW_EH_PE_omit;
+ cieInfo->personalityEncoding = 0;
+ cieInfo->personalityOffsetInCIE = 0;
+ cieInfo->personality = 0;
+ cieInfo->codeAlignFactor = 0;
+ cieInfo->dataAlignFactor = 0;
+ cieInfo->isSignalFrame = false;
+ cieInfo->fdesHaveAugmentationData = false;
+ cieInfo->cieStart = cie;
+ pint_t p = cie;
+ pint_t cieLength = (pint_t)addressSpace.get32(p);
+ p += 4;
+ pint_t cieContentEnd = p + cieLength;
+ if (cieLength == 0xffffffff) {
+ // 0xffffffff means length is really next 8 bytes
+ cieLength = (pint_t)addressSpace.get64(p);
+ p += 8;
+ cieContentEnd = p + cieLength;
+ }
+ if (cieLength == 0)
+ return NULL;
+ // CIE ID is always 0
+ if (addressSpace.get32(p) != 0)
+ return "CIE ID is not zero";
+ p += 4;
+ // Version is always 1 or 3
+ uint8_t version = addressSpace.get8(p);
+ if ((version != 1) && (version != 3))
+ return "CIE version is not 1 or 3";
+ ++p;
+ // save start of augmentation string and find end
+ pint_t strStart = p;
+ while (addressSpace.get8(p) != 0)
+ ++p;
+ ++p;
+ // parse code aligment factor
+ cieInfo->codeAlignFactor = (uint32_t)addressSpace.getULEB128(p, cieContentEnd);
+ // parse data alignment factor
+ cieInfo->dataAlignFactor = (int)addressSpace.getSLEB128(p, cieContentEnd);
+ // parse return address register
+ uint64_t raReg = addressSpace.getULEB128(p, cieContentEnd);
+ assert(raReg < 255 && "return address register too large");
+ cieInfo->returnAddressRegister = (uint8_t)raReg;
+ // parse augmentation data based on augmentation string
+ const char *result = NULL;
+ if (addressSpace.get8(strStart) == 'z') {
+ // parse augmentation data length
+ addressSpace.getULEB128(p, cieContentEnd);
+ for (pint_t s = strStart; addressSpace.get8(s) != '\0'; ++s) {
+ switch (addressSpace.get8(s)) {
+ case 'z':
+ cieInfo->fdesHaveAugmentationData = true;
+ break;
+ case 'P':
+ cieInfo->personalityEncoding = addressSpace.get8(p);
+ ++p;
+ cieInfo->personalityOffsetInCIE = (uint8_t)(p - cie);
+ cieInfo->personality = addressSpace
+ .getEncodedP(p, cieContentEnd, cieInfo->personalityEncoding);
+ break;
+ case 'L':
+ cieInfo->lsdaEncoding = addressSpace.get8(p);
+ ++p;
+ break;
+ case 'R':
+ cieInfo->pointerEncoding = addressSpace.get8(p);
+ ++p;
+ break;
+ case 'S':
+ cieInfo->isSignalFrame = true;
+ break;
+ default:
+ // ignore unknown letters
+ break;
+ }
+ }
+ }
+ cieInfo->cieLength = cieContentEnd - cieInfo->cieStart;
+ cieInfo->cieInstructions = p;
+ return result;
+}
+
+
+/// "run" the dwarf instructions and create the abstact PrologInfo for an FDE
+template <typename A>
+bool CFI_Parser<A>::parseFDEInstructions(A &addressSpace,
+ const FDE_Info &fdeInfo,
+ const CIE_Info &cieInfo, pint_t upToPC,
+ PrologInfo *results) {
+ // clear results
+ memset(results, '\0', sizeof(PrologInfo));
+ PrologInfoStackEntry *rememberStack = NULL;
+
+ // parse CIE then FDE instructions
+ return parseInstructions(addressSpace, cieInfo.cieInstructions,
+ cieInfo.cieStart + cieInfo.cieLength, cieInfo,
+ (pint_t)(-1), rememberStack, results) &&
+ parseInstructions(addressSpace, fdeInfo.fdeInstructions,
+ fdeInfo.fdeStart + fdeInfo.fdeLength, cieInfo,
+ upToPC - fdeInfo.pcStart, rememberStack, results);
+}
+
+/// "run" the dwarf instructions
+template <typename A>
+bool CFI_Parser<A>::parseInstructions(A &addressSpace, pint_t instructions,
+ pint_t instructionsEnd,
+ const CIE_Info &cieInfo, pint_t pcoffset,
+ PrologInfoStackEntry *&rememberStack,
+ PrologInfo *results) {
+ const bool logDwarf = false;
+ pint_t p = instructions;
+ pint_t codeOffset = 0;
+ PrologInfo initialState = *results;
+ if (logDwarf)
+ fprintf(stderr, "parseInstructions(instructions=0x%0" PRIx64 ")\n",
+ (uint64_t)instructionsEnd);
+
+ // see Dwarf Spec, section 6.4.2 for details on unwind opcodes
+ while ((p < instructionsEnd) && (codeOffset < pcoffset)) {
+ uint64_t reg;
+ uint64_t reg2;
+ int64_t offset;
+ uint64_t length;
+ uint8_t opcode = addressSpace.get8(p);
+ uint8_t operand;
+ PrologInfoStackEntry *entry;
+ ++p;
+ switch (opcode) {
+ case DW_CFA_nop:
+ if (logDwarf)
+ fprintf(stderr, "DW_CFA_nop\n");
+ break;
+ case DW_CFA_set_loc:
+ codeOffset =
+ addressSpace.getEncodedP(p, instructionsEnd, cieInfo.pointerEncoding);
+ if (logDwarf)
+ fprintf(stderr, "DW_CFA_set_loc\n");
+ break;
+ case DW_CFA_advance_loc1:
+ codeOffset += (addressSpace.get8(p) * cieInfo.codeAlignFactor);
+ p += 1;
+ if (logDwarf)
+ fprintf(stderr, "DW_CFA_advance_loc1: new offset=%" PRIu64 "\n",
+ (uint64_t)codeOffset);
+ break;
+ case DW_CFA_advance_loc2:
+ codeOffset += (addressSpace.get16(p) * cieInfo.codeAlignFactor);
+ p += 2;
+ if (logDwarf)
+ fprintf(stderr, "DW_CFA_advance_loc2: new offset=%" PRIu64 "\n",
+ (uint64_t)codeOffset);
+ break;
+ case DW_CFA_advance_loc4:
+ codeOffset += (addressSpace.get32(p) * cieInfo.codeAlignFactor);
+ p += 4;
+ if (logDwarf)
+ fprintf(stderr, "DW_CFA_advance_loc4: new offset=%" PRIu64 "\n",
+ (uint64_t)codeOffset);
+ break;
+ case DW_CFA_offset_extended:
+ reg = addressSpace.getULEB128(p, instructionsEnd);
+ offset = (int64_t)addressSpace.getULEB128(p, instructionsEnd)
+ * cieInfo.dataAlignFactor;
+ if (reg > kMaxRegisterNumber) {
+ fprintf(stderr,
+ "malformed DW_CFA_offset_extended dwarf unwind, reg too big\n");
+ return false;
+ }
+ results->savedRegisters[reg].location = kRegisterInCFA;
+ results->savedRegisters[reg].value = offset;
+ if (logDwarf)
+ fprintf(stderr,
+ "DW_CFA_offset_extended(reg=%" PRIu64 ", offset=%" PRId64 ")\n",
+ reg, offset);
+ break;
+ case DW_CFA_restore_extended:
+ reg = addressSpace.getULEB128(p, instructionsEnd);
+ ;
+ if (reg > kMaxRegisterNumber) {
+ fprintf(
+ stderr,
+ "malformed DW_CFA_restore_extended dwarf unwind, reg too big\n");
+ return false;
+ }
+ results->savedRegisters[reg] = initialState.savedRegisters[reg];
+ if (logDwarf)
+ fprintf(stderr, "DW_CFA_restore_extended(reg=%" PRIu64 ")\n", reg);
+ break;
+ case DW_CFA_undefined:
+ reg = addressSpace.getULEB128(p, instructionsEnd);
+ if (reg > kMaxRegisterNumber) {
+ fprintf(stderr,
+ "malformed DW_CFA_undefined dwarf unwind, reg too big\n");
+ return false;
+ }
+ results->savedRegisters[reg].location = kRegisterUnused;
+ if (logDwarf)
+ fprintf(stderr, "DW_CFA_undefined(reg=%" PRIu64 ")\n", reg);
+ break;
+ case DW_CFA_same_value:
+ reg = addressSpace.getULEB128(p, instructionsEnd);
+ if (reg > kMaxRegisterNumber) {
+ fprintf(stderr,
+ "malformed DW_CFA_same_value dwarf unwind, reg too big\n");
+ return false;
+ }
+ // <rdar://problem/8456377> DW_CFA_same_value unsupported
+ // "same value" means register was stored in frame, but its current
+ // value has not changed, so no need to restore from frame.
+ // We model this as if the register was never saved.
+ results->savedRegisters[reg].location = kRegisterUnused;
+ // set flag to disable conversion to compact unwind
+ results->sameValueUsed = true;
+ if (logDwarf)
+ fprintf(stderr, "DW_CFA_same_value(reg=%" PRIu64 ")\n", reg);
+ break;
+ case DW_CFA_register:
+ reg = addressSpace.getULEB128(p, instructionsEnd);
+ reg2 = addressSpace.getULEB128(p, instructionsEnd);
+ if (reg > kMaxRegisterNumber) {
+ fprintf(stderr,
+ "malformed DW_CFA_register dwarf unwind, reg too big\n");
+ return false;
+ }
+ if (reg2 > kMaxRegisterNumber) {
+ fprintf(stderr,
+ "malformed DW_CFA_register dwarf unwind, reg2 too big\n");
+ return false;
+ }
+ results->savedRegisters[reg].location = kRegisterInRegister;
+ results->savedRegisters[reg].value = (int64_t)reg2;
+ // set flag to disable conversion to compact unwind
+ results->registersInOtherRegisters = true;
+ if (logDwarf)
+ fprintf(stderr, "DW_CFA_register(reg=%" PRIu64 ", reg2=%" PRIu64 ")\n",
+ reg, reg2);
+ break;
+ case DW_CFA_remember_state:
+ // avoid operator new, because that would be an upward dependency
+ entry = (PrologInfoStackEntry *)malloc(sizeof(PrologInfoStackEntry));
+ if (entry != NULL) {
+ entry->next = rememberStack;
+ entry->info = *results;
+ rememberStack = entry;
+ } else {
+ return false;
+ }
+ if (logDwarf)
+ fprintf(stderr, "DW_CFA_remember_state\n");
+ break;
+ case DW_CFA_restore_state:
+ if (rememberStack != NULL) {
+ PrologInfoStackEntry *top = rememberStack;
+ *results = top->info;
+ rememberStack = top->next;
+ free((char *)top);
+ } else {
+ return false;
+ }
+ if (logDwarf)
+ fprintf(stderr, "DW_CFA_restore_state\n");
+ break;
+ case DW_CFA_def_cfa:
+ reg = addressSpace.getULEB128(p, instructionsEnd);
+ offset = (int64_t)addressSpace.getULEB128(p, instructionsEnd);
+ if (reg > kMaxRegisterNumber) {
+ fprintf(stderr, "malformed DW_CFA_def_cfa dwarf unwind, reg too big\n");
+ return false;
+ }
+ results->cfaRegister = (uint32_t)reg;
+ results->cfaRegisterOffset = (int32_t)offset;
+ if (logDwarf)
+ fprintf(stderr, "DW_CFA_def_cfa(reg=%" PRIu64 ", offset=%" PRIu64 ")\n",
+ reg, offset);
+ break;
+ case DW_CFA_def_cfa_register:
+ reg = addressSpace.getULEB128(p, instructionsEnd);
+ if (reg > kMaxRegisterNumber) {
+ fprintf(
+ stderr,
+ "malformed DW_CFA_def_cfa_register dwarf unwind, reg too big\n");
+ return false;
+ }
+ results->cfaRegister = (uint32_t)reg;
+ if (logDwarf)
+ fprintf(stderr, "DW_CFA_def_cfa_register(%" PRIu64 ")\n", reg);
+ break;
+ case DW_CFA_def_cfa_offset:
+ results->cfaRegisterOffset = (int32_t)
+ addressSpace.getULEB128(p, instructionsEnd);
+ results->codeOffsetAtStackDecrement = (uint32_t)codeOffset;
+ if (logDwarf)
+ fprintf(stderr, "DW_CFA_def_cfa_offset(%d)\n",
+ results->cfaRegisterOffset);
+ break;
+ case DW_CFA_def_cfa_expression:
+ results->cfaRegister = 0;
+ results->cfaExpression = (int64_t)p;
+ length = addressSpace.getULEB128(p, instructionsEnd);
+ p += length;
+ if (logDwarf)
+ fprintf(stderr, "DW_CFA_def_cfa_expression(expression=0x%" PRIx64
+ ", length=%" PRIu64 ")\n",
+ results->cfaExpression, length);
+ break;
+ case DW_CFA_expression:
+ reg = addressSpace.getULEB128(p, instructionsEnd);
+ if (reg > kMaxRegisterNumber) {
+ fprintf(stderr,
+ "malformed DW_CFA_expression dwarf unwind, reg too big\n");
+ return false;
+ }
+ results->savedRegisters[reg].location = kRegisterAtExpression;
+ results->savedRegisters[reg].value = (int64_t)p;
+ length = addressSpace.getULEB128(p, instructionsEnd);
+ p += length;
+ if (logDwarf)
+ fprintf(stderr, "DW_CFA_expression(reg=%" PRIu64
+ ", expression=0x%" PRIx64 ", length=%" PRIu64 ")\n",
+ reg, results->savedRegisters[reg].value, length);
+ break;
+ case DW_CFA_offset_extended_sf:
+ reg = addressSpace.getULEB128(p, instructionsEnd);
+ if (reg > kMaxRegisterNumber) {
+ fprintf(
+ stderr,
+ "malformed DW_CFA_offset_extended_sf dwarf unwind, reg too big\n");
+ return false;
+ }
+ offset =
+ addressSpace.getSLEB128(p, instructionsEnd) * cieInfo.dataAlignFactor;
+ results->savedRegisters[reg].location = kRegisterInCFA;
+ results->savedRegisters[reg].value = offset;
+ if (logDwarf)
+ fprintf(stderr, "DW_CFA_offset_extended_sf(reg=%" PRIu64
+ ", offset=%" PRId64 ")\n",
+ reg, offset);
+ break;
+ case DW_CFA_def_cfa_sf:
+ reg = addressSpace.getULEB128(p, instructionsEnd);
+ offset =
+ addressSpace.getSLEB128(p, instructionsEnd) * cieInfo.dataAlignFactor;
+ if (reg > kMaxRegisterNumber) {
+ fprintf(stderr,
+ "malformed DW_CFA_def_cfa_sf dwarf unwind, reg too big\n");
+ return false;
+ }
+ results->cfaRegister = (uint32_t)reg;
+ results->cfaRegisterOffset = (int32_t)offset;
+ if (logDwarf)
+ fprintf(stderr,
+ "DW_CFA_def_cfa_sf(reg=%" PRIu64 ", offset=%" PRId64 ")\n", reg,
+ offset);
+ break;
+ case DW_CFA_def_cfa_offset_sf:
+ results->cfaRegisterOffset = (int32_t)
+ (addressSpace.getSLEB128(p, instructionsEnd) * cieInfo.dataAlignFactor);
+ results->codeOffsetAtStackDecrement = (uint32_t)codeOffset;
+ if (logDwarf)
+ fprintf(stderr, "DW_CFA_def_cfa_offset_sf(%d)\n",
+ results->cfaRegisterOffset);
+ break;
+ case DW_CFA_val_offset:
+ reg = addressSpace.getULEB128(p, instructionsEnd);
+ offset = (int64_t)addressSpace.getULEB128(p, instructionsEnd)
+ * cieInfo.dataAlignFactor;
+ results->savedRegisters[reg].location = kRegisterOffsetFromCFA;
+ results->savedRegisters[reg].value = offset;
+ if (logDwarf)
+ fprintf(stderr,
+ "DW_CFA_val_offset(reg=%" PRIu64 ", offset=%" PRId64 "\n", reg,
+ offset);
+ break;
+ case DW_CFA_val_offset_sf:
+ reg = addressSpace.getULEB128(p, instructionsEnd);
+ if (reg > kMaxRegisterNumber) {
+ fprintf(stderr,
+ "malformed DW_CFA_val_offset_sf dwarf unwind, reg too big\n");
+ return false;
+ }
+ offset =
+ addressSpace.getSLEB128(p, instructionsEnd) * cieInfo.dataAlignFactor;
+ results->savedRegisters[reg].location = kRegisterOffsetFromCFA;
+ results->savedRegisters[reg].value = offset;
+ if (logDwarf)
+ fprintf(stderr,
+ "DW_CFA_val_offset_sf(reg=%" PRIu64 ", offset=%" PRId64 "\n",
+ reg, offset);
+ break;
+ case DW_CFA_val_expression:
+ reg = addressSpace.getULEB128(p, instructionsEnd);
+ if (reg > kMaxRegisterNumber) {
+ fprintf(stderr,
+ "malformed DW_CFA_val_expression dwarf unwind, reg too big\n");
+ return false;
+ }
+ results->savedRegisters[reg].location = kRegisterIsExpression;
+ results->savedRegisters[reg].value = (int64_t)p;
+ length = addressSpace.getULEB128(p, instructionsEnd);
+ p += length;
+ if (logDwarf)
+ fprintf(stderr, "DW_CFA_val_expression(reg=%" PRIu64
+ ", expression=0x%" PRIx64 ", length=%" PRIu64 ")\n",
+ reg, results->savedRegisters[reg].value, length);
+ break;
+ case DW_CFA_GNU_args_size:
+ length = addressSpace.getULEB128(p, instructionsEnd);
+ results->spExtraArgSize = (uint32_t)length;
+ if (logDwarf)
+ fprintf(stderr, "DW_CFA_GNU_args_size(%" PRIu64 ")\n", length);
+ break;
+ case DW_CFA_GNU_negative_offset_extended:
+ reg = addressSpace.getULEB128(p, instructionsEnd);
+ if (reg > kMaxRegisterNumber) {
+ fprintf(stderr, "malformed DW_CFA_GNU_negative_offset_extended dwarf "
+ "unwind, reg too big\n");
+ return false;
+ }
+ offset = (int64_t)addressSpace.getULEB128(p, instructionsEnd)
+ * cieInfo.dataAlignFactor;
+ results->savedRegisters[reg].location = kRegisterInCFA;
+ results->savedRegisters[reg].value = -offset;
+ if (logDwarf)
+ fprintf(stderr, "DW_CFA_GNU_negative_offset_extended(%" PRId64 ")\n",
+ offset);
+ break;
+ default:
+ operand = opcode & 0x3F;
+ switch (opcode & 0xC0) {
+ case DW_CFA_offset:
+ reg = operand;
+ offset = (int64_t)addressSpace.getULEB128(p, instructionsEnd)
+ * cieInfo.dataAlignFactor;
+ results->savedRegisters[reg].location = kRegisterInCFA;
+ results->savedRegisters[reg].value = offset;
+ if (logDwarf)
+ fprintf(stderr, "DW_CFA_offset(reg=%d, offset=%" PRId64 ")\n",
+ operand, offset);
+ break;
+ case DW_CFA_advance_loc:
+ codeOffset += operand * cieInfo.codeAlignFactor;
+ if (logDwarf)
+ fprintf(stderr, "DW_CFA_advance_loc: new offset=%" PRIu64 "\n",
+ (uint64_t)codeOffset);
+ break;
+ case DW_CFA_restore:
+ reg = operand;
+ results->savedRegisters[reg] = initialState.savedRegisters[reg];
+ if (logDwarf)
+ fprintf(stderr, "DW_CFA_restore(reg=%" PRIu64 ")\n", reg);
+ break;
+ default:
+ if (logDwarf)
+ fprintf(stderr, "unknown CFA opcode 0x%02X\n", opcode);
+ return false;
+ }
+ }
+ }
+
+ return true;
+}
+
+} // namespace libunwind
+
+#endif // __DWARF_PARSER_HPP__