[llvm] [CodeView] Move Triple::ArchType → CPUType mapping from LLDB

[mgorny]

Summary

Since neither the CodeView::CPUType nor Triple::ArchType constants are
specific to LLDB, it makes no sense to maintain their mapping there.
Instead, introduce a small inline function to provide the mapping
in CodeView, and provide a convenience overload of getRegisterNames().

[compnerd]

llvm/include/llvm/DebugInfo/CodeView/CodeView.h

145

I that aarch64_be and aarch64_32 should be included in this.

147

This is still wrong. x86 and armv7 are totally legitimate values. Furthermore, x86 is still far more prevalent on Windows.

[mgorny]

llvm/include/llvm/DebugInfo/CodeView/CodeView.h

147

Could you be more specific, please? Are you asking me to cover more input values?

Which option do you suggest mapping x86 into? Pentium3?

[mtrent]

I am not familiar with lldb or with the DebugView library, so I am pulling in Fred Riss for this review. Thanks!

lldb/source/Plugins/SymbolFile/NativePDB/PdbFPOProgramToDWARFExpression.cpp

 #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);
+      llvm::codeview::getRegisterNames(arch_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;

llvm/include/llvm/DebugInfo/CodeView/CodeView.h

 //===----------------------------------------------------------------------===//
 
 #ifndef LLVM_DEBUGINFO_CODEVIEW_CODEVIEW_H
 #define LLVM_DEBUGINFO_CODEVIEW_CODEVIEW_H
 
 #include <cinttypes>
 #include <type_traits>
 
+#include "llvm/ADT/Triple.h"
 #include "llvm/Support/Endian.h"
 
 namespace llvm {
 namespace codeview {
 
 /// Distinguishes individual records in .debug$T or .debug$P section or PDB type
 /// stream. The documentation and headers talk about this as the "leaf" type.
 enum class TypeRecordKind : uint16_t {
enum class CPUType : uint16_t {
   TriCore = 0xc0,
   X64 = 0xd0,
   EBC = 0xe0,
   Thumb = 0xf0,
   ARMNT = 0xf4,
   D3D11_Shader = 0x100,
 };
 
+/// Convert llvm::Triple::ArchType value into llvm::codeview::CPUType.
+inline CPUType getCPUTypeForArchType(const Triple::ArchType &ArchType) {
+  switch (ArchType) {
+  case Triple::ArchType::aarch64:
+    return CPUType::ARM64;
+  default:
+    return CPUType::X64;
+  }
+}
+
 /// These values correspond to the CV_CFL_LANG enumeration, and are documented
 /// here: https://msdn.microsoft.com/en-us/library/bw3aekw6.aspx
 enum SourceLanguage : uint8_t {
   C = 0x00,
   Cpp = 0x01,
   Fortran = 0x02,
   Masm = 0x03,
   Pascal = 0x04,

llvm/include/llvm/DebugInfo/CodeView/EnumTables.h

 //===- EnumTables.h - Enum to string conversion tables ----------*- 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
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef LLVM_DEBUGINFO_CODEVIEW_ENUMTABLES_H
 #define LLVM_DEBUGINFO_CODEVIEW_ENUMTABLES_H
 
 #include "llvm/ADT/ArrayRef.h"
+#include "llvm/ADT/Triple.h"
 #include "llvm/BinaryFormat/COFF.h"
 #include "llvm/DebugInfo/CodeView/CodeView.h"
 #include "llvm/Support/ScopedPrinter.h"
 #include <cstdint>
 
 namespace llvm {
 namespace codeview {
 

 ArrayRef<EnumEntry<uint32_t>> getFrameProcSymFlagNames();
 ArrayRef<EnumEntry<uint16_t>> getExportSymFlagNames();
 ArrayRef<EnumEntry<uint32_t>> getModuleSubstreamKindNames();
 ArrayRef<EnumEntry<uint8_t>> getThunkOrdinalNames();
 ArrayRef<EnumEntry<uint16_t>> getTrampolineNames();
 ArrayRef<EnumEntry<COFF::SectionCharacteristics>>
 getImageSectionCharacteristicNames();
 
+inline ArrayRef<EnumEntry<uint16_t>>
+getRegisterNames(Triple::ArchType ArchType) {
+  return getRegisterNames(getCPUTypeForArchType(ArchType));
+}
+
 } // end namespace codeview
 } // end namespace llvm
 
 #endif // LLVM_DEBUGINFO_CODEVIEW_ENUMTABLES_H