28e2256a1f
This patch introduces support for the DWARF operation `DW_OP_GNU_implicit_pointer `(value 0xf3) within LLVM's DWARF parsing and expression evaluation infrastructure. This GNU extension is used to describe the location of a variable that is itself a pointer, where the value of this pointer is stored at an address derived from another DWARF location expression plus a constant offset. Motivation: Compilers like GCC use `DW_OP_GNU_implicit_pointer `to represent the location of certain variables.Without support for this opcode, debuggers like LLDB (and other tools relying on LLVM's DWARF libraries) cannot correctly resolve the location of such variables, leading to an inability to inspect their values or an incorrect debugging experience.
564 lines
20 KiB
C++
564 lines
20 KiB
C++
//===-- DWARFExpression.cpp -----------------------------------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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#include "llvm/DebugInfo/DWARF/DWARFExpression.h"
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#include "llvm/ADT/SmallString.h"
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#include "llvm/DebugInfo/DWARF/DWARFUnit.h"
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#include "llvm/Support/Format.h"
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#include <cassert>
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#include <cstdint>
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#include <vector>
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using namespace llvm;
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using namespace dwarf;
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namespace llvm {
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typedef DWARFExpression::Operation Op;
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typedef Op::Description Desc;
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static std::vector<Desc> getOpDescriptions() {
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std::vector<Desc> Descriptions;
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Descriptions.resize(0xff);
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Descriptions[DW_OP_addr] = Desc(Op::Dwarf2, Op::SizeAddr);
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Descriptions[DW_OP_deref] = Desc(Op::Dwarf2);
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Descriptions[DW_OP_const1u] = Desc(Op::Dwarf2, Op::Size1);
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Descriptions[DW_OP_const1s] = Desc(Op::Dwarf2, Op::SignedSize1);
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Descriptions[DW_OP_const2u] = Desc(Op::Dwarf2, Op::Size2);
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Descriptions[DW_OP_const2s] = Desc(Op::Dwarf2, Op::SignedSize2);
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Descriptions[DW_OP_const4u] = Desc(Op::Dwarf2, Op::Size4);
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Descriptions[DW_OP_const4s] = Desc(Op::Dwarf2, Op::SignedSize4);
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Descriptions[DW_OP_const8u] = Desc(Op::Dwarf2, Op::Size8);
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Descriptions[DW_OP_const8s] = Desc(Op::Dwarf2, Op::SignedSize8);
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Descriptions[DW_OP_constu] = Desc(Op::Dwarf2, Op::SizeLEB);
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Descriptions[DW_OP_consts] = Desc(Op::Dwarf2, Op::SignedSizeLEB);
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Descriptions[DW_OP_dup] = Desc(Op::Dwarf2);
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Descriptions[DW_OP_drop] = Desc(Op::Dwarf2);
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Descriptions[DW_OP_over] = Desc(Op::Dwarf2);
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Descriptions[DW_OP_pick] = Desc(Op::Dwarf2, Op::Size1);
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Descriptions[DW_OP_swap] = Desc(Op::Dwarf2);
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Descriptions[DW_OP_rot] = Desc(Op::Dwarf2);
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Descriptions[DW_OP_xderef] = Desc(Op::Dwarf2);
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Descriptions[DW_OP_abs] = Desc(Op::Dwarf2);
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Descriptions[DW_OP_and] = Desc(Op::Dwarf2);
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Descriptions[DW_OP_div] = Desc(Op::Dwarf2);
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Descriptions[DW_OP_minus] = Desc(Op::Dwarf2);
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Descriptions[DW_OP_mod] = Desc(Op::Dwarf2);
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Descriptions[DW_OP_mul] = Desc(Op::Dwarf2);
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Descriptions[DW_OP_neg] = Desc(Op::Dwarf2);
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Descriptions[DW_OP_not] = Desc(Op::Dwarf2);
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Descriptions[DW_OP_or] = Desc(Op::Dwarf2);
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Descriptions[DW_OP_plus] = Desc(Op::Dwarf2);
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Descriptions[DW_OP_plus_uconst] = Desc(Op::Dwarf2, Op::SizeLEB);
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Descriptions[DW_OP_shl] = Desc(Op::Dwarf2);
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Descriptions[DW_OP_shr] = Desc(Op::Dwarf2);
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Descriptions[DW_OP_shra] = Desc(Op::Dwarf2);
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Descriptions[DW_OP_xor] = Desc(Op::Dwarf2);
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Descriptions[DW_OP_bra] = Desc(Op::Dwarf2, Op::SignedSize2);
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Descriptions[DW_OP_eq] = Desc(Op::Dwarf2);
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Descriptions[DW_OP_ge] = Desc(Op::Dwarf2);
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Descriptions[DW_OP_gt] = Desc(Op::Dwarf2);
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Descriptions[DW_OP_le] = Desc(Op::Dwarf2);
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Descriptions[DW_OP_lt] = Desc(Op::Dwarf2);
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Descriptions[DW_OP_ne] = Desc(Op::Dwarf2);
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Descriptions[DW_OP_skip] = Desc(Op::Dwarf2, Op::SignedSize2);
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for (uint16_t LA = DW_OP_lit0; LA <= DW_OP_lit31; ++LA)
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Descriptions[LA] = Desc(Op::Dwarf2);
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for (uint16_t LA = DW_OP_reg0; LA <= DW_OP_reg31; ++LA)
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Descriptions[LA] = Desc(Op::Dwarf2);
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for (uint16_t LA = DW_OP_breg0; LA <= DW_OP_breg31; ++LA)
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Descriptions[LA] = Desc(Op::Dwarf2, Op::SignedSizeLEB);
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Descriptions[DW_OP_regx] = Desc(Op::Dwarf2, Op::SizeLEB);
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Descriptions[DW_OP_fbreg] = Desc(Op::Dwarf2, Op::SignedSizeLEB);
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Descriptions[DW_OP_bregx] = Desc(Op::Dwarf2, Op::SizeLEB, Op::SignedSizeLEB);
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Descriptions[DW_OP_piece] = Desc(Op::Dwarf2, Op::SizeLEB);
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Descriptions[DW_OP_deref_size] = Desc(Op::Dwarf2, Op::Size1);
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Descriptions[DW_OP_xderef_size] = Desc(Op::Dwarf2, Op::Size1);
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Descriptions[DW_OP_nop] = Desc(Op::Dwarf2);
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Descriptions[DW_OP_push_object_address] = Desc(Op::Dwarf3);
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Descriptions[DW_OP_call2] = Desc(Op::Dwarf3, Op::Size2);
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Descriptions[DW_OP_call4] = Desc(Op::Dwarf3, Op::Size4);
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Descriptions[DW_OP_call_ref] = Desc(Op::Dwarf3, Op::SizeRefAddr);
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Descriptions[DW_OP_form_tls_address] = Desc(Op::Dwarf3);
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Descriptions[DW_OP_call_frame_cfa] = Desc(Op::Dwarf3);
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Descriptions[DW_OP_bit_piece] = Desc(Op::Dwarf3, Op::SizeLEB, Op::SizeLEB);
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Descriptions[DW_OP_implicit_value] =
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Desc(Op::Dwarf4, Op::SizeLEB, Op::SizeBlock);
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Descriptions[DW_OP_stack_value] = Desc(Op::Dwarf4);
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Descriptions[DW_OP_implicit_pointer] =
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Desc(Op::Dwarf5, Op::SizeRefAddr, Op::SignedSizeLEB);
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Descriptions[DW_OP_addrx] = Desc(Op::Dwarf5, Op::SizeLEB);
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Descriptions[DW_OP_constx] = Desc(Op::Dwarf5, Op::SizeLEB);
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Descriptions[DW_OP_entry_value] = Desc(Op::Dwarf5, Op::SizeLEB);
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Descriptions[DW_OP_convert] = Desc(Op::Dwarf5, Op::BaseTypeRef);
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Descriptions[DW_OP_regval_type] =
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Desc(Op::Dwarf5, Op::SizeLEB, Op::BaseTypeRef);
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Descriptions[DW_OP_WASM_location] =
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Desc(Op::Dwarf4, Op::SizeLEB, Op::WasmLocationArg);
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Descriptions[DW_OP_GNU_push_tls_address] = Desc(Op::Dwarf3);
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Descriptions[DW_OP_GNU_addr_index] = Desc(Op::Dwarf4, Op::SizeLEB);
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Descriptions[DW_OP_GNU_const_index] = Desc(Op::Dwarf4, Op::SizeLEB);
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Descriptions[DW_OP_GNU_entry_value] = Desc(Op::Dwarf4, Op::SizeLEB);
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Descriptions[DW_OP_GNU_implicit_pointer] =
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Desc(Op::Dwarf4, Op::SizeRefAddr, Op::SignedSizeLEB);
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// This Description acts as a marker that getSubOpDesc must be called
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// to fetch the final Description for the operation. Each such final
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// Description must share the same first SizeSubOpLEB operand.
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Descriptions[DW_OP_LLVM_user] = Desc(Op::Dwarf5, Op::SizeSubOpLEB);
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return Descriptions;
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}
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static Desc getDescImpl(ArrayRef<Desc> Descriptions, unsigned Opcode) {
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// Handle possible corrupted or unsupported operation.
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if (Opcode >= Descriptions.size())
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return {};
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return Descriptions[Opcode];
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}
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static Desc getOpDesc(unsigned Opcode) {
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static std::vector<Desc> Descriptions = getOpDescriptions();
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return getDescImpl(Descriptions, Opcode);
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}
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static std::vector<Desc> getSubOpDescriptions() {
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static constexpr unsigned LlvmUserDescriptionsSize = 1
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#define HANDLE_DW_OP_LLVM_USEROP(ID, NAME) +1
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#include "llvm/BinaryFormat/Dwarf.def"
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;
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std::vector<Desc> Descriptions;
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Descriptions.resize(LlvmUserDescriptionsSize);
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Descriptions[DW_OP_LLVM_nop] = Desc(Op::Dwarf5, Op::SizeSubOpLEB);
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return Descriptions;
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}
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static Desc getSubOpDesc(unsigned Opcode, unsigned SubOpcode) {
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assert(Opcode == DW_OP_LLVM_user);
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static std::vector<Desc> Descriptions = getSubOpDescriptions();
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return getDescImpl(Descriptions, SubOpcode);
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}
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bool DWARFExpression::Operation::extract(DataExtractor Data,
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uint8_t AddressSize, uint64_t Offset,
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std::optional<DwarfFormat> Format) {
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EndOffset = Offset;
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Opcode = Data.getU8(&Offset);
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Desc = getOpDesc(Opcode);
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if (Desc.Version == Operation::DwarfNA)
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return false;
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Operands.resize(Desc.Op.size());
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OperandEndOffsets.resize(Desc.Op.size());
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for (unsigned Operand = 0; Operand < Desc.Op.size(); ++Operand) {
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unsigned Size = Desc.Op[Operand];
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unsigned Signed = Size & Operation::SignBit;
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switch (Size & ~Operation::SignBit) {
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case Operation::SizeSubOpLEB:
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assert(Operand == 0 && "SubOp operand must be the first operand");
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Operands[Operand] = Data.getULEB128(&Offset);
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Desc = getSubOpDesc(Opcode, Operands[Operand]);
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if (Desc.Version == Operation::DwarfNA)
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return false;
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assert(Desc.Op[Operand] == Operation::SizeSubOpLEB &&
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"SizeSubOpLEB Description must begin with SizeSubOpLEB operand");
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break;
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case Operation::Size1:
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Operands[Operand] = Data.getU8(&Offset);
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if (Signed)
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Operands[Operand] = (int8_t)Operands[Operand];
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break;
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case Operation::Size2:
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Operands[Operand] = Data.getU16(&Offset);
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if (Signed)
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Operands[Operand] = (int16_t)Operands[Operand];
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break;
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case Operation::Size4:
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Operands[Operand] = Data.getU32(&Offset);
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if (Signed)
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Operands[Operand] = (int32_t)Operands[Operand];
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break;
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case Operation::Size8:
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Operands[Operand] = Data.getU64(&Offset);
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break;
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case Operation::SizeAddr:
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Operands[Operand] = Data.getUnsigned(&Offset, AddressSize);
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break;
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case Operation::SizeRefAddr:
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if (!Format)
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return false;
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Operands[Operand] =
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Data.getUnsigned(&Offset, dwarf::getDwarfOffsetByteSize(*Format));
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break;
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case Operation::SizeLEB:
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if (Signed)
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Operands[Operand] = Data.getSLEB128(&Offset);
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else
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Operands[Operand] = Data.getULEB128(&Offset);
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break;
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case Operation::BaseTypeRef:
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Operands[Operand] = Data.getULEB128(&Offset);
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break;
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case Operation::WasmLocationArg:
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assert(Operand == 1);
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switch (Operands[0]) {
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case 0:
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case 1:
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case 2:
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case 4:
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Operands[Operand] = Data.getULEB128(&Offset);
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break;
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case 3: // global as uint32
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Operands[Operand] = Data.getU32(&Offset);
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break;
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default:
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return false; // Unknown Wasm location
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}
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break;
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case Operation::SizeBlock:
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// We need a size, so this cannot be the first operand
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if (Operand == 0)
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return false;
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// Store the offset of the block as the value.
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Operands[Operand] = Offset;
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Offset += Operands[Operand - 1];
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break;
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default:
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llvm_unreachable("Unknown DWARFExpression Op size");
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}
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OperandEndOffsets[Operand] = Offset;
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}
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EndOffset = Offset;
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return true;
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}
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static void prettyPrintBaseTypeRef(DWARFUnit *U, raw_ostream &OS,
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DIDumpOptions DumpOpts,
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ArrayRef<uint64_t> Operands,
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unsigned Operand) {
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assert(Operand < Operands.size() && "operand out of bounds");
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if (!U) {
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OS << format(" <base_type ref: 0x%" PRIx64 ">", Operands[Operand]);
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return;
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}
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auto Die = U->getDIEForOffset(U->getOffset() + Operands[Operand]);
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if (Die && Die.getTag() == dwarf::DW_TAG_base_type) {
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OS << " (";
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if (DumpOpts.Verbose)
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OS << format("0x%08" PRIx64 " -> ", Operands[Operand]);
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OS << format("0x%08" PRIx64 ")", U->getOffset() + Operands[Operand]);
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if (auto Name = dwarf::toString(Die.find(dwarf::DW_AT_name)))
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OS << " \"" << *Name << "\"";
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} else {
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OS << format(" <invalid base_type ref: 0x%" PRIx64 ">", Operands[Operand]);
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}
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}
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bool DWARFExpression::prettyPrintRegisterOp(DWARFUnit *U, raw_ostream &OS,
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DIDumpOptions DumpOpts,
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uint8_t Opcode,
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ArrayRef<uint64_t> Operands) {
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if (!DumpOpts.GetNameForDWARFReg)
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return false;
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uint64_t DwarfRegNum;
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unsigned OpNum = 0;
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if (Opcode == DW_OP_bregx || Opcode == DW_OP_regx ||
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Opcode == DW_OP_regval_type)
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DwarfRegNum = Operands[OpNum++];
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else if (Opcode >= DW_OP_breg0 && Opcode < DW_OP_bregx)
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DwarfRegNum = Opcode - DW_OP_breg0;
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else
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DwarfRegNum = Opcode - DW_OP_reg0;
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auto RegName = DumpOpts.GetNameForDWARFReg(DwarfRegNum, DumpOpts.IsEH);
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if (!RegName.empty()) {
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if ((Opcode >= DW_OP_breg0 && Opcode <= DW_OP_breg31) ||
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Opcode == DW_OP_bregx)
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OS << ' ' << RegName << format("%+" PRId64, Operands[OpNum]);
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else
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OS << ' ' << RegName.data();
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if (Opcode == DW_OP_regval_type)
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prettyPrintBaseTypeRef(U, OS, DumpOpts, Operands, 1);
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return true;
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}
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return false;
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}
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std::optional<unsigned> DWARFExpression::Operation::getSubCode() const {
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if (!Desc.Op.size() || Desc.Op[0] != Operation::SizeSubOpLEB)
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return std::nullopt;
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return Operands[0];
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}
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bool DWARFExpression::Operation::print(raw_ostream &OS, DIDumpOptions DumpOpts,
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const DWARFExpression *Expr,
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DWARFUnit *U) const {
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if (Error) {
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OS << "<decoding error>";
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return false;
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}
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StringRef Name = OperationEncodingString(Opcode);
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assert(!Name.empty() && "DW_OP has no name!");
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OS << Name;
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if ((Opcode >= DW_OP_breg0 && Opcode <= DW_OP_breg31) ||
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(Opcode >= DW_OP_reg0 && Opcode <= DW_OP_reg31) ||
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Opcode == DW_OP_bregx || Opcode == DW_OP_regx ||
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Opcode == DW_OP_regval_type)
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if (prettyPrintRegisterOp(U, OS, DumpOpts, Opcode, Operands))
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return true;
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for (unsigned Operand = 0; Operand < Desc.Op.size(); ++Operand) {
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unsigned Size = Desc.Op[Operand];
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unsigned Signed = Size & Operation::SignBit;
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if (Size == Operation::SizeSubOpLEB) {
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StringRef SubName = SubOperationEncodingString(Opcode, Operands[Operand]);
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assert(!SubName.empty() && "DW_OP SubOp has no name!");
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OS << " " << SubName;
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} else if (Size == Operation::BaseTypeRef && U) {
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// For DW_OP_convert the operand may be 0 to indicate that conversion to
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// the generic type should be done. The same holds for DW_OP_reinterpret,
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// which is currently not supported.
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if (Opcode == DW_OP_convert && Operands[Operand] == 0)
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OS << " 0x0";
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else
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prettyPrintBaseTypeRef(U, OS, DumpOpts, Operands, Operand);
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} else if (Size == Operation::WasmLocationArg) {
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assert(Operand == 1);
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switch (Operands[0]) {
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case 0:
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case 1:
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case 2:
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case 3: // global as uint32
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case 4:
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OS << format(" 0x%" PRIx64, Operands[Operand]);
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break;
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default: assert(false);
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}
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} else if (Size == Operation::SizeBlock) {
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uint64_t Offset = Operands[Operand];
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for (unsigned i = 0; i < Operands[Operand - 1]; ++i)
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OS << format(" 0x%02x", Expr->Data.getU8(&Offset));
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} else {
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if (Signed)
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OS << format(" %+" PRId64, (int64_t)Operands[Operand]);
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else if (Opcode != DW_OP_entry_value &&
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Opcode != DW_OP_GNU_entry_value)
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OS << format(" 0x%" PRIx64, Operands[Operand]);
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}
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}
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return true;
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}
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void DWARFExpression::print(raw_ostream &OS, DIDumpOptions DumpOpts,
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DWARFUnit *U, bool IsEH) const {
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uint32_t EntryValExprSize = 0;
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uint64_t EntryValStartOffset = 0;
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if (Data.getData().empty())
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OS << "<empty>";
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for (auto &Op : *this) {
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DumpOpts.IsEH = IsEH;
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if (!Op.print(OS, DumpOpts, this, U)) {
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uint64_t FailOffset = Op.getEndOffset();
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while (FailOffset < Data.getData().size())
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OS << format(" %02x", Data.getU8(&FailOffset));
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return;
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}
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if (Op.getCode() == DW_OP_entry_value ||
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Op.getCode() == DW_OP_GNU_entry_value) {
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OS << "(";
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EntryValExprSize = Op.getRawOperand(0);
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EntryValStartOffset = Op.getEndOffset();
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continue;
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}
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if (EntryValExprSize) {
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EntryValExprSize -= Op.getEndOffset() - EntryValStartOffset;
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if (EntryValExprSize == 0)
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OS << ")";
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}
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if (Op.getEndOffset() < Data.getData().size())
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OS << ", ";
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}
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}
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bool DWARFExpression::Operation::verify(const Operation &Op, DWARFUnit *U) {
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for (unsigned Operand = 0; Operand < Op.Desc.Op.size(); ++Operand) {
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unsigned Size = Op.Desc.Op[Operand];
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if (Size == Operation::BaseTypeRef) {
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// For DW_OP_convert the operand may be 0 to indicate that conversion to
|
|
// the generic type should be done, so don't look up a base type in that
|
|
// case. The same holds for DW_OP_reinterpret, which is currently not
|
|
// supported.
|
|
if (Op.Opcode == DW_OP_convert && Op.Operands[Operand] == 0)
|
|
continue;
|
|
auto Die = U->getDIEForOffset(U->getOffset() + Op.Operands[Operand]);
|
|
if (!Die || Die.getTag() != dwarf::DW_TAG_base_type)
|
|
return false;
|
|
}
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
bool DWARFExpression::verify(DWARFUnit *U) {
|
|
for (auto &Op : *this)
|
|
if (!Operation::verify(Op, U))
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
/// A user-facing string representation of a DWARF expression. This might be an
|
|
/// Address expression, in which case it will be implicitly dereferenced, or a
|
|
/// Value expression.
|
|
struct PrintedExpr {
|
|
enum ExprKind {
|
|
Address,
|
|
Value,
|
|
};
|
|
ExprKind Kind;
|
|
SmallString<16> String;
|
|
|
|
PrintedExpr(ExprKind K = Address) : Kind(K) {}
|
|
};
|
|
|
|
static bool printCompactDWARFExpr(
|
|
raw_ostream &OS, DWARFExpression::iterator I,
|
|
const DWARFExpression::iterator E,
|
|
std::function<StringRef(uint64_t RegNum, bool IsEH)> GetNameForDWARFReg =
|
|
nullptr) {
|
|
SmallVector<PrintedExpr, 4> Stack;
|
|
|
|
while (I != E) {
|
|
const DWARFExpression::Operation &Op = *I;
|
|
uint8_t Opcode = Op.getCode();
|
|
switch (Opcode) {
|
|
case dwarf::DW_OP_regx: {
|
|
// DW_OP_regx: A register, with the register num given as an operand.
|
|
// Printed as the plain register name.
|
|
uint64_t DwarfRegNum = Op.getRawOperand(0);
|
|
auto RegName = GetNameForDWARFReg(DwarfRegNum, false);
|
|
if (RegName.empty())
|
|
return false;
|
|
raw_svector_ostream S(Stack.emplace_back(PrintedExpr::Value).String);
|
|
S << RegName;
|
|
break;
|
|
}
|
|
case dwarf::DW_OP_bregx: {
|
|
int DwarfRegNum = Op.getRawOperand(0);
|
|
int64_t Offset = Op.getRawOperand(1);
|
|
auto RegName = GetNameForDWARFReg(DwarfRegNum, false);
|
|
if (RegName.empty())
|
|
return false;
|
|
raw_svector_ostream S(Stack.emplace_back().String);
|
|
S << RegName;
|
|
if (Offset)
|
|
S << format("%+" PRId64, Offset);
|
|
break;
|
|
}
|
|
case dwarf::DW_OP_entry_value:
|
|
case dwarf::DW_OP_GNU_entry_value: {
|
|
// DW_OP_entry_value contains a sub-expression which must be rendered
|
|
// separately.
|
|
uint64_t SubExprLength = Op.getRawOperand(0);
|
|
DWARFExpression::iterator SubExprEnd = I.skipBytes(SubExprLength);
|
|
++I;
|
|
raw_svector_ostream S(Stack.emplace_back().String);
|
|
S << "entry(";
|
|
printCompactDWARFExpr(S, I, SubExprEnd, GetNameForDWARFReg);
|
|
S << ")";
|
|
I = SubExprEnd;
|
|
continue;
|
|
}
|
|
case dwarf::DW_OP_stack_value: {
|
|
// The top stack entry should be treated as the actual value of tne
|
|
// variable, rather than the address of the variable in memory.
|
|
assert(!Stack.empty());
|
|
Stack.back().Kind = PrintedExpr::Value;
|
|
break;
|
|
}
|
|
case dwarf::DW_OP_nop: {
|
|
break;
|
|
}
|
|
case dwarf::DW_OP_LLVM_user: {
|
|
assert(Op.getSubCode() && *Op.getSubCode() == dwarf::DW_OP_LLVM_nop);
|
|
break;
|
|
}
|
|
default:
|
|
if (Opcode >= dwarf::DW_OP_reg0 && Opcode <= dwarf::DW_OP_reg31) {
|
|
// DW_OP_reg<N>: A register, with the register num implied by the
|
|
// opcode. Printed as the plain register name.
|
|
uint64_t DwarfRegNum = Opcode - dwarf::DW_OP_reg0;
|
|
auto RegName = GetNameForDWARFReg(DwarfRegNum, false);
|
|
if (RegName.empty())
|
|
return false;
|
|
raw_svector_ostream S(Stack.emplace_back(PrintedExpr::Value).String);
|
|
S << RegName;
|
|
} else if (Opcode >= dwarf::DW_OP_breg0 &&
|
|
Opcode <= dwarf::DW_OP_breg31) {
|
|
int DwarfRegNum = Opcode - dwarf::DW_OP_breg0;
|
|
int64_t Offset = Op.getRawOperand(0);
|
|
auto RegName = GetNameForDWARFReg(DwarfRegNum, false);
|
|
if (RegName.empty())
|
|
return false;
|
|
raw_svector_ostream S(Stack.emplace_back().String);
|
|
S << RegName;
|
|
if (Offset)
|
|
S << format("%+" PRId64, Offset);
|
|
} else {
|
|
// If we hit an unknown operand, we don't know its effect on the stack,
|
|
// so bail out on the whole expression.
|
|
OS << "<unknown op " << dwarf::OperationEncodingString(Opcode) << " ("
|
|
<< (int)Opcode << ")>";
|
|
return false;
|
|
}
|
|
break;
|
|
}
|
|
++I;
|
|
}
|
|
|
|
if (Stack.size() != 1) {
|
|
OS << "<stack of size " << Stack.size() << ", expected 1>";
|
|
return false;
|
|
}
|
|
|
|
if (Stack.front().Kind == PrintedExpr::Address)
|
|
OS << "[" << Stack.front().String << "]";
|
|
else
|
|
OS << Stack.front().String;
|
|
|
|
return true;
|
|
}
|
|
|
|
bool DWARFExpression::printCompact(
|
|
raw_ostream &OS,
|
|
std::function<StringRef(uint64_t RegNum, bool IsEH)> GetNameForDWARFReg) {
|
|
return printCompactDWARFExpr(OS, begin(), end(), GetNameForDWARFReg);
|
|
}
|
|
|
|
bool DWARFExpression::operator==(const DWARFExpression &RHS) const {
|
|
if (AddressSize != RHS.AddressSize || Format != RHS.Format)
|
|
return false;
|
|
return Data.getData() == RHS.Data.getData();
|
|
}
|
|
|
|
} // namespace llvm
|