1 files changed, 300 insertions, 0 deletions
diff --git a/contrib/llvm-project/lldb/source/Plugins/SymbolFile/NativePDB/DWARFLocationExpression.cpp b/contrib/llvm-project/lldb/source/Plugins/SymbolFile/NativePDB/DWARFLocationExpression.cpp
new file mode 100644
index 000000000000..75adf7302f00
--- /dev/null
+++ b/contrib/llvm-project/lldb/source/Plugins/SymbolFile/NativePDB/DWARFLocationExpression.cpp
@@ -0,0 +1,300 @@
+//===-- DWARFLocationExpression.cpp ---------------------------------------===//
+//
+// 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 "DWARFLocationExpression.h"
+
+#include "lldb/Core/Module.h"
+#include "lldb/Core/Section.h"
+#include "lldb/Expression/DWARFExpression.h"
+#include "lldb/Utility/ArchSpec.h"
+#include "lldb/Utility/DataBufferHeap.h"
+#include "lldb/Utility/StreamBuffer.h"
+
+#include "llvm/BinaryFormat/Dwarf.h"
+#include "llvm/DebugInfo/CodeView/TypeDeserializer.h"
+#include "llvm/DebugInfo/CodeView/TypeIndex.h"
+#include "llvm/DebugInfo/PDB/Native/TpiStream.h"
+#include "llvm/Support/Endian.h"
+
+#include "PdbUtil.h"
+#include "CodeViewRegisterMapping.h"
+#include "PdbFPOProgramToDWARFExpression.h"
+#include <optional>
+
+using namespace lldb;
+using namespace lldb_private;
+using namespace lldb_private::npdb;
+using namespace llvm::codeview;
+using namespace llvm::pdb;
+
+uint32_t GetGenericRegisterNumber(llvm::codeview::RegisterId register_id) {
+  if (register_id == llvm::codeview::RegisterId::VFRAME)
+    return LLDB_REGNUM_GENERIC_FP;
+
+  return LLDB_INVALID_REGNUM;
+}
+
+static uint32_t GetRegisterNumber(llvm::Triple::ArchType arch_type,
+                                  llvm::codeview::RegisterId register_id,
+                                  RegisterKind &register_kind) {
+  register_kind = eRegisterKindLLDB;
+  uint32_t reg_num = GetLLDBRegisterNumber(arch_type, register_id);
+  if (reg_num != LLDB_INVALID_REGNUM)
+    return reg_num;
+
+  register_kind = eRegisterKindGeneric;
+  return GetGenericRegisterNumber(register_id);
+}
+
+static bool IsSimpleTypeSignedInteger(SimpleTypeKind kind) {
+  switch (kind) {
+  case SimpleTypeKind::Int128:
+  case SimpleTypeKind::Int64:
+  case SimpleTypeKind::Int64Quad:
+  case SimpleTypeKind::Int32:
+  case SimpleTypeKind::Int32Long:
+  case SimpleTypeKind::Int16:
+  case SimpleTypeKind::Int16Short:
+  case SimpleTypeKind::Float128:
+  case SimpleTypeKind::Float80:
+  case SimpleTypeKind::Float64:
+  case SimpleTypeKind::Float32:
+  case SimpleTypeKind::Float16:
+  case SimpleTypeKind::NarrowCharacter:
+  case SimpleTypeKind::SignedCharacter:
+  case SimpleTypeKind::SByte:
+    return true;
+  default:
+    return false;
+  }
+}
+
+static std::pair<size_t, bool> GetIntegralTypeInfo(TypeIndex ti,
+                                                   TpiStream &tpi) {
+  if (ti.isSimple()) {
+    SimpleTypeKind stk = ti.getSimpleKind();
+    return {GetTypeSizeForSimpleKind(stk), IsSimpleTypeSignedInteger(stk)};
+  }
+
+  CVType cvt = tpi.getType(ti);
+  switch (cvt.kind()) {
+  case LF_MODIFIER: {
+    ModifierRecord mfr;
+    llvm::cantFail(TypeDeserializer::deserializeAs<ModifierRecord>(cvt, mfr));
+    return GetIntegralTypeInfo(mfr.ModifiedType, tpi);
+  }
+  case LF_POINTER: {
+    PointerRecord pr;
+    llvm::cantFail(TypeDeserializer::deserializeAs<PointerRecord>(cvt, pr));
+    return GetIntegralTypeInfo(pr.ReferentType, tpi);
+  }
+  case LF_ENUM: {
+    EnumRecord er;
+    llvm::cantFail(TypeDeserializer::deserializeAs<EnumRecord>(cvt, er));
+    return GetIntegralTypeInfo(er.UnderlyingType, tpi);
+  }
+  default:
+    assert(false && "Type is not integral!");
+    return {0, false};
+  }
+}
+
+template <typename StreamWriter>
+static DWARFExpression MakeLocationExpressionInternal(lldb::ModuleSP module,
+                                                      StreamWriter &&writer) {
+  const ArchSpec &architecture = module->GetArchitecture();
+  ByteOrder byte_order = architecture.GetByteOrder();
+  uint32_t address_size = architecture.GetAddressByteSize();
+  uint32_t byte_size = architecture.GetDataByteSize();
+  if (byte_order == eByteOrderInvalid || address_size == 0)
+    return DWARFExpression();
+
+  RegisterKind register_kind = eRegisterKindDWARF;
+  StreamBuffer<32> stream(Stream::eBinary, address_size, byte_order);
+
+  if (!writer(stream, register_kind))
+    return DWARFExpression();
+
+  DataBufferSP buffer =
+      std::make_shared<DataBufferHeap>(stream.GetData(), stream.GetSize());
+  DataExtractor extractor(buffer, byte_order, address_size, byte_size);
+  DWARFExpression result(extractor);
+  result.SetRegisterKind(register_kind);
+
+  return result;
+}
+
+static bool MakeRegisterBasedLocationExpressionInternal(
+    Stream &stream, llvm::codeview::RegisterId reg, RegisterKind &register_kind,
+    std::optional<int32_t> relative_offset, lldb::ModuleSP module) {
+  uint32_t reg_num = GetRegisterNumber(module->GetArchitecture().GetMachine(),
+                                       reg, register_kind);
+  if (reg_num == LLDB_INVALID_REGNUM)
+    return false;
+
+  if (reg_num > 31) {
+    llvm::dwarf::LocationAtom base =
+        relative_offset ? llvm::dwarf::DW_OP_bregx : llvm::dwarf::DW_OP_regx;
+    stream.PutHex8(base);
+    stream.PutULEB128(reg_num);
+  } else {
+    llvm::dwarf::LocationAtom base =
+        relative_offset ? llvm::dwarf::DW_OP_breg0 : llvm::dwarf::DW_OP_reg0;
+    stream.PutHex8(base + reg_num);
+  }
+
+  if (relative_offset)
+    stream.PutSLEB128(*relative_offset);
+
+  return true;
+}
+
+static DWARFExpression MakeRegisterBasedLocationExpressionInternal(
+    llvm::codeview::RegisterId reg, std::optional<int32_t> relative_offset,
+    lldb::ModuleSP module) {
+  return MakeLocationExpressionInternal(
+      module, [&](Stream &stream, RegisterKind &register_kind) -> bool {
+        return MakeRegisterBasedLocationExpressionInternal(
+            stream, reg, register_kind, relative_offset, module);
+      });
+}
+
+DWARFExpression lldb_private::npdb::MakeEnregisteredLocationExpression(
+    llvm::codeview::RegisterId reg, lldb::ModuleSP module) {
+  return MakeRegisterBasedLocationExpressionInternal(reg, std::nullopt, module);
+}
+
+DWARFExpression lldb_private::npdb::MakeRegRelLocationExpression(
+    llvm::codeview::RegisterId reg, int32_t offset, lldb::ModuleSP module) {
+  return MakeRegisterBasedLocationExpressionInternal(reg, offset, module);
+}
+
+static bool EmitVFrameEvaluationDWARFExpression(
+    llvm::StringRef program, llvm::Triple::ArchType arch_type, Stream &stream) {
+  // VFrame value always stored in $TO pseudo-register
+  return TranslateFPOProgramToDWARFExpression(program, "$T0", arch_type,
+                                              stream);
+}
+
+DWARFExpression lldb_private::npdb::MakeVFrameRelLocationExpression(
+    llvm::StringRef fpo_program, int32_t offset, lldb::ModuleSP module) {
+  return MakeLocationExpressionInternal(
+      module, [&](Stream &stream, RegisterKind &register_kind) -> bool {
+        const ArchSpec &architecture = module->GetArchitecture();
+
+        if (!EmitVFrameEvaluationDWARFExpression(fpo_program, architecture.GetMachine(),
+                                                 stream))
+          return false;
+
+        stream.PutHex8(llvm::dwarf::DW_OP_consts);
+        stream.PutSLEB128(offset);
+        stream.PutHex8(llvm::dwarf::DW_OP_plus);
+
+        register_kind = eRegisterKindLLDB;
+
+        return true;
+      });
+}
+
+DWARFExpression lldb_private::npdb::MakeGlobalLocationExpression(
+    uint16_t section, uint32_t offset, ModuleSP module) {
+  assert(section > 0);
+  assert(module);
+
+  return MakeLocationExpressionInternal(
+      module, [&](Stream &stream, RegisterKind &register_kind) -> bool {
+        stream.PutHex8(llvm::dwarf::DW_OP_addr);
+
+        SectionList *section_list = module->GetSectionList();
+        assert(section_list);
+
+        auto section_ptr = section_list->FindSectionByID(section);
+        if (!section_ptr)
+          return false;
+
+        stream.PutMaxHex64(section_ptr->GetFileAddress() + offset,
+                           stream.GetAddressByteSize(), stream.GetByteOrder());
+
+        return true;
+      });
+}
+
+DWARFExpression lldb_private::npdb::MakeConstantLocationExpression(
+    TypeIndex underlying_ti, TpiStream &tpi, const llvm::APSInt &constant,
+    ModuleSP module) {
+  const ArchSpec &architecture = module->GetArchitecture();
+  uint32_t address_size = architecture.GetAddressByteSize();
+
+  size_t size = 0;
+  bool is_signed = false;
+  std::tie(size, is_signed) = GetIntegralTypeInfo(underlying_ti, tpi);
+
+  union {
+    llvm::support::little64_t I;
+    llvm::support::ulittle64_t U;
+  } Value;
+
+  std::shared_ptr<DataBufferHeap> buffer = std::make_shared<DataBufferHeap>();
+  buffer->SetByteSize(size);
+
+  llvm::ArrayRef<uint8_t> bytes;
+  if (is_signed) {
+    Value.I = constant.getSExtValue();
+  } else {
+    Value.U = constant.getZExtValue();
+  }
+
+  bytes = llvm::ArrayRef(reinterpret_cast<const uint8_t *>(&Value), 8)
+              .take_front(size);
+  buffer->CopyData(bytes.data(), size);
+  DataExtractor extractor(buffer, lldb::eByteOrderLittle, address_size);
+  DWARFExpression result(extractor);
+  return result;
+}
+
+DWARFExpression
+lldb_private::npdb::MakeEnregisteredLocationExpressionForComposite(
+    const std::map<uint64_t, MemberValLocation> &offset_to_location,
+    std::map<uint64_t, size_t> &offset_to_size, size_t total_size,
+    lldb::ModuleSP module) {
+  return MakeLocationExpressionInternal(
+      module, [&](Stream &stream, RegisterKind &register_kind) -> bool {
+        size_t cur_offset = 0;
+        bool is_simple_type = offset_to_size.empty();
+        // Iterate through offset_to_location because offset_to_size might be
+        // empty if the variable is a simple type.
+        for (const auto &offset_loc : offset_to_location) {
+          if (cur_offset < offset_loc.first) {
+            stream.PutHex8(llvm::dwarf::DW_OP_piece);
+            stream.PutULEB128(offset_loc.first - cur_offset);
+            cur_offset = offset_loc.first;
+          }
+          MemberValLocation loc = offset_loc.second;
+          std::optional<int32_t> offset =
+              loc.is_at_reg ? std::nullopt
+                            : std::optional<int32_t>(loc.reg_offset);
+          if (!MakeRegisterBasedLocationExpressionInternal(
+                  stream, (RegisterId)loc.reg_id, register_kind, offset,
+                  module))
+            return false;
+          if (!is_simple_type) {
+            stream.PutHex8(llvm::dwarf::DW_OP_piece);
+            stream.PutULEB128(offset_to_size[offset_loc.first]);
+            cur_offset = offset_loc.first + offset_to_size[offset_loc.first];
+          }
+        }
+        // For simple type, it specifies the byte size of the value described by
+        // the previous dwarf expr. For udt, it's the remaining byte size at end
+        // of a struct.
+        if (total_size > cur_offset) {
+          stream.PutHex8(llvm::dwarf::DW_OP_piece);
+          stream.PutULEB128(total_size - cur_offset);
+        }
+        return true;
+      });
+}