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-rw-r--r--src/DwarfInstructions.hpp760
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diff --git a/src/DwarfInstructions.hpp b/src/DwarfInstructions.hpp
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+++ b/src/DwarfInstructions.hpp
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+//===-------------------------- DwarfInstructions.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.
+//
+//
+// Processor specific interpretation of dwarf unwind info.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef __DWARF_INSTRUCTIONS_HPP__
+#define __DWARF_INSTRUCTIONS_HPP__
+
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "dwarf2.h"
+#include "AddressSpace.hpp"
+#include "Registers.hpp"
+#include "DwarfParser.hpp"
+#include "config.h"
+
+
+namespace libunwind {
+
+
+/// DwarfInstructions maps abtract dwarf unwind instructions to a particular
+/// architecture
+template <typename A, typename R>
+class DwarfInstructions {
+public:
+ typedef typename A::pint_t pint_t;
+ typedef typename A::sint_t sint_t;
+
+ static int stepWithDwarf(A &addressSpace, pint_t pc, pint_t fdeStart,
+ R &registers);
+
+private:
+
+ enum {
+ DW_X86_64_RET_ADDR = 16
+ };
+
+ enum {
+ DW_X86_RET_ADDR = 8
+ };
+
+ typedef typename CFI_Parser<A>::RegisterLocation RegisterLocation;
+ typedef typename CFI_Parser<A>::PrologInfo PrologInfo;
+ typedef typename CFI_Parser<A>::FDE_Info FDE_Info;
+ typedef typename CFI_Parser<A>::CIE_Info CIE_Info;
+
+ static pint_t evaluateExpression(pint_t expression, A &addressSpace,
+ const R &registers,
+ pint_t initialStackValue);
+ static pint_t getSavedRegister(A &addressSpace, const R &registers,
+ pint_t cfa, const RegisterLocation &savedReg);
+ static double getSavedFloatRegister(A &addressSpace, const R &registers,
+ pint_t cfa, const RegisterLocation &savedReg);
+ static v128 getSavedVectorRegister(A &addressSpace, const R &registers,
+ pint_t cfa, const RegisterLocation &savedReg);
+
+ static pint_t getCFA(A &addressSpace, const PrologInfo &prolog,
+ const R &registers) {
+ if (prolog.cfaRegister != 0)
+ return (pint_t)((sint_t)registers.getRegister((int)prolog.cfaRegister) +
+ prolog.cfaRegisterOffset);
+ if (prolog.cfaExpression != 0)
+ return evaluateExpression((pint_t)prolog.cfaExpression, addressSpace,
+ registers, 0);
+ assert(0 && "getCFA(): unknown location");
+ __builtin_unreachable();
+ }
+};
+
+
+template <typename A, typename R>
+typename A::pint_t DwarfInstructions<A, R>::getSavedRegister(
+ A &addressSpace, const R &registers, pint_t cfa,
+ const RegisterLocation &savedReg) {
+ switch (savedReg.location) {
+ case CFI_Parser<A>::kRegisterInCFA:
+ return addressSpace.getP(cfa + (pint_t)savedReg.value);
+
+ case CFI_Parser<A>::kRegisterAtExpression:
+ return addressSpace.getP(
+ evaluateExpression((pint_t)savedReg.value, addressSpace,
+ registers, cfa));
+
+ case CFI_Parser<A>::kRegisterIsExpression:
+ return evaluateExpression((pint_t)savedReg.value, addressSpace,
+ registers, cfa);
+
+ case CFI_Parser<A>::kRegisterInRegister:
+ return registers.getRegister((int)savedReg.value);
+
+ case CFI_Parser<A>::kRegisterUnused:
+ case CFI_Parser<A>::kRegisterOffsetFromCFA:
+ // FIX ME
+ break;
+ }
+ _LIBUNWIND_ABORT("unsupported restore location for register");
+}
+
+template <typename A, typename R>
+double DwarfInstructions<A, R>::getSavedFloatRegister(
+ A &addressSpace, const R &registers, pint_t cfa,
+ const RegisterLocation &savedReg) {
+ switch (savedReg.location) {
+ case CFI_Parser<A>::kRegisterInCFA:
+ return addressSpace.getDouble(cfa + (pint_t)savedReg.value);
+
+ case CFI_Parser<A>::kRegisterAtExpression:
+ return addressSpace.getDouble(
+ evaluateExpression((pint_t)savedReg.value, addressSpace,
+ registers, cfa));
+
+ case CFI_Parser<A>::kRegisterIsExpression:
+ case CFI_Parser<A>::kRegisterUnused:
+ case CFI_Parser<A>::kRegisterOffsetFromCFA:
+ case CFI_Parser<A>::kRegisterInRegister:
+ // FIX ME
+ break;
+ }
+ _LIBUNWIND_ABORT("unsupported restore location for float register");
+}
+
+template <typename A, typename R>
+v128 DwarfInstructions<A, R>::getSavedVectorRegister(
+ A &addressSpace, const R &registers, pint_t cfa,
+ const RegisterLocation &savedReg) {
+ switch (savedReg.location) {
+ case CFI_Parser<A>::kRegisterInCFA:
+ return addressSpace.getVector(cfa + (pint_t)savedReg.value);
+
+ case CFI_Parser<A>::kRegisterAtExpression:
+ return addressSpace.getVector(
+ evaluateExpression((pint_t)savedReg.value, addressSpace,
+ registers, cfa));
+
+ case CFI_Parser<A>::kRegisterIsExpression:
+ case CFI_Parser<A>::kRegisterUnused:
+ case CFI_Parser<A>::kRegisterOffsetFromCFA:
+ case CFI_Parser<A>::kRegisterInRegister:
+ // FIX ME
+ break;
+ }
+ _LIBUNWIND_ABORT("unsupported restore location for vector register");
+}
+
+template <typename A, typename R>
+int DwarfInstructions<A, R>::stepWithDwarf(A &addressSpace, pint_t pc,
+ pint_t fdeStart, R &registers) {
+ FDE_Info fdeInfo;
+ CIE_Info cieInfo;
+ if (CFI_Parser<A>::decodeFDE(addressSpace, fdeStart, &fdeInfo,
+ &cieInfo) == NULL) {
+ PrologInfo prolog;
+ if (CFI_Parser<A>::parseFDEInstructions(addressSpace, fdeInfo, cieInfo, pc,
+ &prolog)) {
+ // get pointer to cfa (architecture specific)
+ pint_t cfa = getCFA(addressSpace, prolog, registers);
+
+ // restore registers that dwarf says were saved
+ R newRegisters = registers;
+ pint_t returnAddress = 0;
+ const int lastReg = R::lastDwarfRegNum();
+ assert((int)CFI_Parser<A>::kMaxRegisterNumber > lastReg &&
+ "register range too large");
+ assert(lastReg >= (int)cieInfo.returnAddressRegister &&
+ "register range does not contain return address register");
+ for (int i = 0; i <= lastReg; ++i) {
+ if (prolog.savedRegisters[i].location !=
+ CFI_Parser<A>::kRegisterUnused) {
+ if (registers.validFloatRegister(i))
+ newRegisters.setFloatRegister(
+ i, getSavedFloatRegister(addressSpace, registers, cfa,
+ prolog.savedRegisters[i]));
+ else if (registers.validVectorRegister(i))
+ newRegisters.setVectorRegister(
+ i, getSavedVectorRegister(addressSpace, registers, cfa,
+ prolog.savedRegisters[i]));
+ else if (i == (int)cieInfo.returnAddressRegister)
+ returnAddress = getSavedRegister(addressSpace, registers, cfa,
+ prolog.savedRegisters[i]);
+ else if (registers.validRegister(i))
+ newRegisters.setRegister(
+ i, getSavedRegister(addressSpace, registers, cfa,
+ prolog.savedRegisters[i]));
+ else
+ return UNW_EBADREG;
+ }
+ }
+
+ // By definition, the CFA is the stack pointer at the call site, so
+ // restoring SP means setting it to CFA.
+ newRegisters.setSP(cfa);
+
+ // Return address is address after call site instruction, so setting IP to
+ // that does simualates a return.
+ newRegisters.setIP(returnAddress);
+
+ // Simulate the step by replacing the register set with the new ones.
+ registers = newRegisters;
+
+ return UNW_STEP_SUCCESS;
+ }
+ }
+ return UNW_EBADFRAME;
+}
+
+template <typename A, typename R>
+typename A::pint_t
+DwarfInstructions<A, R>::evaluateExpression(pint_t expression, A &addressSpace,
+ const R &registers,
+ pint_t initialStackValue) {
+ const bool log = false;
+ pint_t p = expression;
+ pint_t expressionEnd = expression + 20; // temp, until len read
+ pint_t length = (pint_t)addressSpace.getULEB128(p, expressionEnd);
+ expressionEnd = p + length;
+ if (log)
+ fprintf(stderr, "evaluateExpression(): length=%" PRIu64 "\n",
+ (uint64_t)length);
+ pint_t stack[100];
+ pint_t *sp = stack;
+ *(++sp) = initialStackValue;
+
+ while (p < expressionEnd) {
+ if (log) {
+ for (pint_t *t = sp; t > stack; --t) {
+ fprintf(stderr, "sp[] = 0x%" PRIx64 "\n", (uint64_t)(*t));
+ }
+ }
+ uint8_t opcode = addressSpace.get8(p++);
+ sint_t svalue, svalue2;
+ pint_t value;
+ uint32_t reg;
+ switch (opcode) {
+ case DW_OP_addr:
+ // push immediate address sized value
+ value = addressSpace.getP(p);
+ p += sizeof(pint_t);
+ *(++sp) = value;
+ if (log)
+ fprintf(stderr, "push 0x%" PRIx64 "\n", (uint64_t)value);
+ break;
+
+ case DW_OP_deref:
+ // pop stack, dereference, push result
+ value = *sp--;
+ *(++sp) = addressSpace.getP(value);
+ if (log)
+ fprintf(stderr, "dereference 0x%" PRIx64 "\n", (uint64_t)value);
+ break;
+
+ case DW_OP_const1u:
+ // push immediate 1 byte value
+ value = addressSpace.get8(p);
+ p += 1;
+ *(++sp) = value;
+ if (log)
+ fprintf(stderr, "push 0x%" PRIx64 "\n", (uint64_t)value);
+ break;
+
+ case DW_OP_const1s:
+ // push immediate 1 byte signed value
+ svalue = (int8_t) addressSpace.get8(p);
+ p += 1;
+ *(++sp) = (pint_t)svalue;
+ if (log)
+ fprintf(stderr, "push 0x%" PRIx64 "\n", (uint64_t)svalue);
+ break;
+
+ case DW_OP_const2u:
+ // push immediate 2 byte value
+ value = addressSpace.get16(p);
+ p += 2;
+ *(++sp) = value;
+ if (log)
+ fprintf(stderr, "push 0x%" PRIx64 "\n", (uint64_t)value);
+ break;
+
+ case DW_OP_const2s:
+ // push immediate 2 byte signed value
+ svalue = (int16_t) addressSpace.get16(p);
+ p += 2;
+ *(++sp) = (pint_t)svalue;
+ if (log)
+ fprintf(stderr, "push 0x%" PRIx64 "\n", (uint64_t)svalue);
+ break;
+
+ case DW_OP_const4u:
+ // push immediate 4 byte value
+ value = addressSpace.get32(p);
+ p += 4;
+ *(++sp) = value;
+ if (log)
+ fprintf(stderr, "push 0x%" PRIx64 "\n", (uint64_t)value);
+ break;
+
+ case DW_OP_const4s:
+ // push immediate 4 byte signed value
+ svalue = (int32_t)addressSpace.get32(p);
+ p += 4;
+ *(++sp) = (pint_t)svalue;
+ if (log)
+ fprintf(stderr, "push 0x%" PRIx64 "\n", (uint64_t)svalue);
+ break;
+
+ case DW_OP_const8u:
+ // push immediate 8 byte value
+ value = (pint_t)addressSpace.get64(p);
+ p += 8;
+ *(++sp) = value;
+ if (log)
+ fprintf(stderr, "push 0x%" PRIx64 "\n", (uint64_t)value);
+ break;
+
+ case DW_OP_const8s:
+ // push immediate 8 byte signed value
+ value = (pint_t)addressSpace.get64(p);
+ p += 8;
+ *(++sp) = value;
+ if (log)
+ fprintf(stderr, "push 0x%" PRIx64 "\n", (uint64_t)value);
+ break;
+
+ case DW_OP_constu:
+ // push immediate ULEB128 value
+ value = (pint_t)addressSpace.getULEB128(p, expressionEnd);
+ *(++sp) = value;
+ if (log)
+ fprintf(stderr, "push 0x%" PRIx64 "\n", (uint64_t)value);
+ break;
+
+ case DW_OP_consts:
+ // push immediate SLEB128 value
+ svalue = (sint_t)addressSpace.getSLEB128(p, expressionEnd);
+ *(++sp) = (pint_t)svalue;
+ if (log)
+ fprintf(stderr, "push 0x%" PRIx64 "\n", (uint64_t)svalue);
+ break;
+
+ case DW_OP_dup:
+ // push top of stack
+ value = *sp;
+ *(++sp) = value;
+ if (log)
+ fprintf(stderr, "duplicate top of stack\n");
+ break;
+
+ case DW_OP_drop:
+ // pop
+ --sp;
+ if (log)
+ fprintf(stderr, "pop top of stack\n");
+ break;
+
+ case DW_OP_over:
+ // dup second
+ value = sp[-1];
+ *(++sp) = value;
+ if (log)
+ fprintf(stderr, "duplicate second in stack\n");
+ break;
+
+ case DW_OP_pick:
+ // pick from
+ reg = addressSpace.get8(p);
+ p += 1;
+ value = sp[-reg];
+ *(++sp) = value;
+ if (log)
+ fprintf(stderr, "duplicate %d in stack\n", reg);
+ break;
+
+ case DW_OP_swap:
+ // swap top two
+ value = sp[0];
+ sp[0] = sp[-1];
+ sp[-1] = value;
+ if (log)
+ fprintf(stderr, "swap top of stack\n");
+ break;
+
+ case DW_OP_rot:
+ // rotate top three
+ value = sp[0];
+ sp[0] = sp[-1];
+ sp[-1] = sp[-2];
+ sp[-2] = value;
+ if (log)
+ fprintf(stderr, "rotate top three of stack\n");
+ break;
+
+ case DW_OP_xderef:
+ // pop stack, dereference, push result
+ value = *sp--;
+ *sp = *((pint_t*)value);
+ if (log)
+ fprintf(stderr, "x-dereference 0x%" PRIx64 "\n", (uint64_t)value);
+ break;
+
+ case DW_OP_abs:
+ svalue = (sint_t)*sp;
+ if (svalue < 0)
+ *sp = (pint_t)(-svalue);
+ if (log)
+ fprintf(stderr, "abs\n");
+ break;
+
+ case DW_OP_and:
+ value = *sp--;
+ *sp &= value;
+ if (log)
+ fprintf(stderr, "and\n");
+ break;
+
+ case DW_OP_div:
+ svalue = (sint_t)(*sp--);
+ svalue2 = (sint_t)*sp;
+ *sp = (pint_t)(svalue2 / svalue);
+ if (log)
+ fprintf(stderr, "div\n");
+ break;
+
+ case DW_OP_minus:
+ value = *sp--;
+ *sp = *sp - value;
+ if (log)
+ fprintf(stderr, "minus\n");
+ break;
+
+ case DW_OP_mod:
+ svalue = (sint_t)(*sp--);
+ svalue2 = (sint_t)*sp;
+ *sp = (pint_t)(svalue2 % svalue);
+ if (log)
+ fprintf(stderr, "module\n");
+ break;
+
+ case DW_OP_mul:
+ svalue = (sint_t)(*sp--);
+ svalue2 = (sint_t)*sp;
+ *sp = (pint_t)(svalue2 * svalue);
+ if (log)
+ fprintf(stderr, "mul\n");
+ break;
+
+ case DW_OP_neg:
+ *sp = 0 - *sp;
+ if (log)
+ fprintf(stderr, "neg\n");
+ break;
+
+ case DW_OP_not:
+ svalue = (sint_t)(*sp);
+ *sp = (pint_t)(~svalue);
+ if (log)
+ fprintf(stderr, "not\n");
+ break;
+
+ case DW_OP_or:
+ value = *sp--;
+ *sp |= value;
+ if (log)
+ fprintf(stderr, "or\n");
+ break;
+
+ case DW_OP_plus:
+ value = *sp--;
+ *sp += value;
+ if (log)
+ fprintf(stderr, "plus\n");
+ break;
+
+ case DW_OP_plus_uconst:
+ // pop stack, add uelb128 constant, push result
+ *sp += addressSpace.getULEB128(p, expressionEnd);
+ if (log)
+ fprintf(stderr, "add constant\n");
+ break;
+
+ case DW_OP_shl:
+ value = *sp--;
+ *sp = *sp << value;
+ if (log)
+ fprintf(stderr, "shift left\n");
+ break;
+
+ case DW_OP_shr:
+ value = *sp--;
+ *sp = *sp >> value;
+ if (log)
+ fprintf(stderr, "shift left\n");
+ break;
+
+ case DW_OP_shra:
+ value = *sp--;
+ svalue = (sint_t)*sp;
+ *sp = (pint_t)(svalue >> value);
+ if (log)
+ fprintf(stderr, "shift left arithmetric\n");
+ break;
+
+ case DW_OP_xor:
+ value = *sp--;
+ *sp ^= value;
+ if (log)
+ fprintf(stderr, "xor\n");
+ break;
+
+ case DW_OP_skip:
+ svalue = (int16_t) addressSpace.get16(p);
+ p += 2;
+ p = (pint_t)((sint_t)p + svalue);
+ if (log)
+ fprintf(stderr, "skip %" PRIu64 "\n", (uint64_t)svalue);
+ break;
+
+ case DW_OP_bra:
+ svalue = (int16_t) addressSpace.get16(p);
+ p += 2;
+ if (*sp--)
+ p = (pint_t)((sint_t)p + svalue);
+ if (log)
+ fprintf(stderr, "bra %" PRIu64 "\n", (uint64_t)svalue);
+ break;
+
+ case DW_OP_eq:
+ value = *sp--;
+ *sp = (*sp == value);
+ if (log)
+ fprintf(stderr, "eq\n");
+ break;
+
+ case DW_OP_ge:
+ value = *sp--;
+ *sp = (*sp >= value);
+ if (log)
+ fprintf(stderr, "ge\n");
+ break;
+
+ case DW_OP_gt:
+ value = *sp--;
+ *sp = (*sp > value);
+ if (log)
+ fprintf(stderr, "gt\n");
+ break;
+
+ case DW_OP_le:
+ value = *sp--;
+ *sp = (*sp <= value);
+ if (log)
+ fprintf(stderr, "le\n");
+ break;
+
+ case DW_OP_lt:
+ value = *sp--;
+ *sp = (*sp < value);
+ if (log)
+ fprintf(stderr, "lt\n");
+ break;
+
+ case DW_OP_ne:
+ value = *sp--;
+ *sp = (*sp != value);
+ if (log)
+ fprintf(stderr, "ne\n");
+ break;
+
+ case DW_OP_lit0:
+ case DW_OP_lit1:
+ case DW_OP_lit2:
+ case DW_OP_lit3:
+ case DW_OP_lit4:
+ case DW_OP_lit5:
+ case DW_OP_lit6:
+ case DW_OP_lit7:
+ case DW_OP_lit8:
+ case DW_OP_lit9:
+ case DW_OP_lit10:
+ case DW_OP_lit11:
+ case DW_OP_lit12:
+ case DW_OP_lit13:
+ case DW_OP_lit14:
+ case DW_OP_lit15:
+ case DW_OP_lit16:
+ case DW_OP_lit17:
+ case DW_OP_lit18:
+ case DW_OP_lit19:
+ case DW_OP_lit20:
+ case DW_OP_lit21:
+ case DW_OP_lit22:
+ case DW_OP_lit23:
+ case DW_OP_lit24:
+ case DW_OP_lit25:
+ case DW_OP_lit26:
+ case DW_OP_lit27:
+ case DW_OP_lit28:
+ case DW_OP_lit29:
+ case DW_OP_lit30:
+ case DW_OP_lit31:
+ value = static_cast<pint_t>(opcode - DW_OP_lit0);
+ *(++sp) = value;
+ if (log)
+ fprintf(stderr, "push literal 0x%" PRIx64 "\n", (uint64_t)value);
+ break;
+
+ case DW_OP_reg0:
+ case DW_OP_reg1:
+ case DW_OP_reg2:
+ case DW_OP_reg3:
+ case DW_OP_reg4:
+ case DW_OP_reg5:
+ case DW_OP_reg6:
+ case DW_OP_reg7:
+ case DW_OP_reg8:
+ case DW_OP_reg9:
+ case DW_OP_reg10:
+ case DW_OP_reg11:
+ case DW_OP_reg12:
+ case DW_OP_reg13:
+ case DW_OP_reg14:
+ case DW_OP_reg15:
+ case DW_OP_reg16:
+ case DW_OP_reg17:
+ case DW_OP_reg18:
+ case DW_OP_reg19:
+ case DW_OP_reg20:
+ case DW_OP_reg21:
+ case DW_OP_reg22:
+ case DW_OP_reg23:
+ case DW_OP_reg24:
+ case DW_OP_reg25:
+ case DW_OP_reg26:
+ case DW_OP_reg27:
+ case DW_OP_reg28:
+ case DW_OP_reg29:
+ case DW_OP_reg30:
+ case DW_OP_reg31:
+ reg = static_cast<uint32_t>(opcode - DW_OP_reg0);
+ *(++sp) = registers.getRegister((int)reg);
+ if (log)
+ fprintf(stderr, "push reg %d\n", reg);
+ break;
+
+ case DW_OP_regx:
+ reg = static_cast<uint32_t>(addressSpace.getULEB128(p, expressionEnd));
+ *(++sp) = registers.getRegister((int)reg);
+ if (log)
+ fprintf(stderr, "push reg %d + 0x%" PRIx64 "\n", reg, (uint64_t)svalue);
+ break;
+
+ case DW_OP_breg0:
+ case DW_OP_breg1:
+ case DW_OP_breg2:
+ case DW_OP_breg3:
+ case DW_OP_breg4:
+ case DW_OP_breg5:
+ case DW_OP_breg6:
+ case DW_OP_breg7:
+ case DW_OP_breg8:
+ case DW_OP_breg9:
+ case DW_OP_breg10:
+ case DW_OP_breg11:
+ case DW_OP_breg12:
+ case DW_OP_breg13:
+ case DW_OP_breg14:
+ case DW_OP_breg15:
+ case DW_OP_breg16:
+ case DW_OP_breg17:
+ case DW_OP_breg18:
+ case DW_OP_breg19:
+ case DW_OP_breg20:
+ case DW_OP_breg21:
+ case DW_OP_breg22:
+ case DW_OP_breg23:
+ case DW_OP_breg24:
+ case DW_OP_breg25:
+ case DW_OP_breg26:
+ case DW_OP_breg27:
+ case DW_OP_breg28:
+ case DW_OP_breg29:
+ case DW_OP_breg30:
+ case DW_OP_breg31:
+ reg = static_cast<uint32_t>(opcode - DW_OP_breg0);
+ svalue = (sint_t)addressSpace.getSLEB128(p, expressionEnd);
+ svalue += static_cast<sint_t>(registers.getRegister((int)reg));
+ *(++sp) = (pint_t)(svalue);
+ if (log)
+ fprintf(stderr, "push reg %d + 0x%" PRIx64 "\n", reg, (uint64_t)svalue);
+ break;
+
+ case DW_OP_bregx:
+ reg = static_cast<uint32_t>(addressSpace.getULEB128(p, expressionEnd));
+ svalue = (sint_t)addressSpace.getSLEB128(p, expressionEnd);
+ svalue += static_cast<sint_t>(registers.getRegister((int)reg));
+ *(++sp) = (pint_t)(svalue);
+ if (log)
+ fprintf(stderr, "push reg %d + 0x%" PRIx64 "\n", reg, (uint64_t)svalue);
+ break;
+
+ case DW_OP_fbreg:
+ _LIBUNWIND_ABORT("DW_OP_fbreg not implemented");
+ break;
+
+ case DW_OP_piece:
+ _LIBUNWIND_ABORT("DW_OP_piece not implemented");
+ break;
+
+ case DW_OP_deref_size:
+ // pop stack, dereference, push result
+ value = *sp--;
+ switch (addressSpace.get8(p++)) {
+ case 1:
+ value = addressSpace.get8(value);
+ break;
+ case 2:
+ value = addressSpace.get16(value);
+ break;
+ case 4:
+ value = addressSpace.get32(value);
+ break;
+ case 8:
+ value = (pint_t)addressSpace.get64(value);
+ break;
+ default:
+ _LIBUNWIND_ABORT("DW_OP_deref_size with bad size");
+ }
+ *(++sp) = value;
+ if (log)
+ fprintf(stderr, "sized dereference 0x%" PRIx64 "\n", (uint64_t)value);
+ break;
+
+ case DW_OP_xderef_size:
+ case DW_OP_nop:
+ case DW_OP_push_object_addres:
+ case DW_OP_call2:
+ case DW_OP_call4:
+ case DW_OP_call_ref:
+ default:
+ _LIBUNWIND_ABORT("dwarf opcode not implemented");
+ }
+
+ }
+ if (log)
+ fprintf(stderr, "expression evaluates to 0x%" PRIx64 "\n", (uint64_t)*sp);
+ return *sp;
+}
+
+
+
+} // namespace libunwind
+
+#endif // __DWARF_INSTRUCTIONS_HPP__