contrib/llvm-project/lldb/source/Plugins/SymbolFile/NativePDB/PdbFPOProgramToDWARFExpression.cpp

   1 //===-- PdbFPOProgramToDWARFExpression.cpp ----------------------*- C++ -*-===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include "PdbFPOProgramToDWARFExpression.h"
  10 #include "CodeViewRegisterMapping.h"
  11
  12 #include "lldb/Core/StreamBuffer.h"
  13 #include "lldb/Symbol/PostfixExpression.h"
  14 #include "lldb/Utility/LLDBAssert.h"
  15 #include "lldb/Utility/Stream.h"
  16 #include "llvm/ADT/DenseMap.h"
  17
  18 #include "llvm/ADT/StringExtras.h"
  19 #include "llvm/DebugInfo/CodeView/CodeView.h"
  20 #include "llvm/DebugInfo/CodeView/EnumTables.h"
  21
  22 using namespace lldb;
  23 using namespace lldb_private;
  24 using namespace lldb_private::postfix;
  25
  26 static uint32_t ResolveLLDBRegisterNum(llvm::StringRef reg_name, llvm::Triple::ArchType arch_type) {
  27   // lookup register name to get lldb register number
  28   llvm::codeview::CPUType cpu_type;
  29   switch (arch_type) {
  30     case llvm::Triple::ArchType::aarch64:
  31       cpu_type = llvm::codeview::CPUType::ARM64;
  32       break;
  33
  34     default:
  35       cpu_type = llvm::codeview::CPUType::X64;
  36       break;
  37   }
  38
  39   llvm::ArrayRef<llvm::EnumEntry<uint16_t>> register_names =
  40       llvm::codeview::getRegisterNames(cpu_type);
  41   auto it = llvm::find_if(
  42       register_names,
  43       [&reg_name](const llvm::EnumEntry<uint16_t> &register_entry) {
  44         return reg_name.compare_lower(register_entry.Name) == 0;
  45       });
  46
  47   if (it == register_names.end())
  48     return LLDB_INVALID_REGNUM;
  49
  50   auto reg_id = static_cast<llvm::codeview::RegisterId>(it->Value);
  51   return npdb::GetLLDBRegisterNumber(arch_type, reg_id);
  52 }
  53
  54 static Node *ResolveFPOProgram(llvm::StringRef program,
  55                              llvm::StringRef register_name,
  56                              llvm::Triple::ArchType arch_type,
  57                              llvm::BumpPtrAllocator &alloc) {
  58   std::vector<std::pair<llvm::StringRef, Node *>> parsed =
  59       postfix::ParseFPOProgram(program, alloc);
  60
  61   for (auto it = parsed.begin(), end = parsed.end(); it != end; ++it) {
  62     // Emplace valid dependent subtrees to make target assignment independent
  63     // from predecessors. Resolve all other SymbolNodes as registers.
  64     bool success =
  65         ResolveSymbols(it->second, [&](SymbolNode &symbol) -> Node * {
  66           for (const auto &pair : llvm::make_range(parsed.begin(), it)) {
  67             if (pair.first == symbol.GetName())
  68               return pair.second;
  69           }
  70
  71           uint32_t reg_num =
  72               ResolveLLDBRegisterNum(symbol.GetName().drop_front(1), arch_type);
  73
  74           if (reg_num == LLDB_INVALID_REGNUM)
  75             return nullptr;
  76
  77           return MakeNode<RegisterNode>(alloc, reg_num);
  78         });
  79     if (!success)
  80       return nullptr;
  81
  82     if (it->first == register_name) {
  83       // found target assignment program - no need to parse further
  84       return it->second;
  85     }
  86   }
  87
  88   return nullptr;
  89 }
  90
  91 bool lldb_private::npdb::TranslateFPOProgramToDWARFExpression(
  92     llvm::StringRef program, llvm::StringRef register_name,
  93     llvm::Triple::ArchType arch_type, Stream &stream) {
  94   llvm::BumpPtrAllocator node_alloc;
  95   Node *target_program =
  96       ResolveFPOProgram(program, register_name, arch_type, node_alloc);
  97   if (target_program == nullptr) {
  98     return false;
  99   }
 100
 101   ToDWARF(*target_program, stream);
 102   return true;
 103 }