llvm-project/lldb/source/Plugins/SymbolFile/NativePDB/PdbFPOProgramToDWARFExpress...

138 lines
4.4 KiB
C++

//===-- PdbFPOProgramToDWARFExpression.cpp ----------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "PdbFPOProgramToDWARFExpression.h"
#include "CodeViewRegisterMapping.h"
#include "lldb/Core/StreamBuffer.h"
#include "lldb/Symbol/PostfixExpression.h"
#include "lldb/Utility/LLDBAssert.h"
#include "lldb/Utility/Stream.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/DebugInfo/CodeView/CodeView.h"
#include "llvm/DebugInfo/CodeView/EnumTables.h"
using namespace lldb;
using namespace lldb_private;
using namespace lldb_private::postfix;
static uint32_t ResolveLLDBRegisterNum(llvm::StringRef reg_name, llvm::Triple::ArchType arch_type) {
// lookup register name to get lldb register number
llvm::codeview::CPUType cpu_type;
switch (arch_type) {
case llvm::Triple::ArchType::aarch64:
cpu_type = llvm::codeview::CPUType::ARM64;
break;
default:
cpu_type = llvm::codeview::CPUType::X64;
break;
}
llvm::ArrayRef<llvm::EnumEntry<uint16_t>> register_names =
llvm::codeview::getRegisterNames(cpu_type);
auto it = llvm::find_if(
register_names,
[&reg_name](const llvm::EnumEntry<uint16_t> &register_entry) {
return reg_name.compare_lower(register_entry.Name) == 0;
});
if (it == register_names.end())
return LLDB_INVALID_REGNUM;
auto reg_id = static_cast<llvm::codeview::RegisterId>(it->Value);
return npdb::GetLLDBRegisterNumber(arch_type, reg_id);
}
static bool ParseFPOSingleAssignmentProgram(llvm::StringRef program,
llvm::BumpPtrAllocator &alloc,
llvm::StringRef &register_name,
Node *&ast) {
// lvalue of assignment is always first token
// rvalue program goes next
std::tie(register_name, program) = getToken(program);
if (register_name.empty())
return false;
ast = Parse(program, alloc);
return ast != nullptr;
}
static Node *ParseFPOProgram(llvm::StringRef program,
llvm::StringRef register_name,
llvm::Triple::ArchType arch_type,
llvm::BumpPtrAllocator &alloc) {
llvm::DenseMap<llvm::StringRef, Node *> dependent_programs;
size_t cur = 0;
while (true) {
size_t assign_index = program.find('=', cur);
if (assign_index == llvm::StringRef::npos) {
llvm::StringRef tail = program.slice(cur, llvm::StringRef::npos);
if (!tail.trim().empty()) {
// missing assign operator
return nullptr;
}
break;
}
llvm::StringRef assignment_program = program.slice(cur, assign_index);
llvm::StringRef lvalue_name;
Node *rvalue_ast = nullptr;
if (!ParseFPOSingleAssignmentProgram(assignment_program, alloc, lvalue_name,
rvalue_ast)) {
return nullptr;
}
lldbassert(rvalue_ast);
// Emplace valid dependent subtrees to make target assignment independent
// from predecessors. Resolve all other SymbolNodes as registers.
bool success =
ResolveSymbols(rvalue_ast, [&](SymbolNode &symbol) -> Node * {
if (Node *node = dependent_programs.lookup(symbol.GetName()))
return node;
uint32_t reg_num =
ResolveLLDBRegisterNum(symbol.GetName().drop_front(1), arch_type);
if (reg_num == LLDB_INVALID_REGNUM)
return nullptr;
return MakeNode<RegisterNode>(alloc, reg_num);
});
if (!success)
return nullptr;
if (lvalue_name == register_name) {
// found target assignment program - no need to parse further
return rvalue_ast;
}
dependent_programs[lvalue_name] = rvalue_ast;
cur = assign_index + 1;
}
return nullptr;
}
bool lldb_private::npdb::TranslateFPOProgramToDWARFExpression(
llvm::StringRef program, llvm::StringRef register_name,
llvm::Triple::ArchType arch_type, Stream &stream) {
llvm::BumpPtrAllocator node_alloc;
Node *target_program =
ParseFPOProgram(program, register_name, arch_type, node_alloc);
if (target_program == nullptr) {
return false;
}
ToDWARF(*target_program, stream);
return true;
}