[COFF] Expose a easier helper function for getting names for relocation types

[mstorsjo]

Summary

The existing method is protected, and requires using DataRefImpl and SmallVector.

This will be used by LLD.

[rnk]

lgtm

lib/Object/COFFObjectFile.cpp

1277–1278

Does Result += getRelocationTypeName(Reloc->Type); work?

[mstorsjo]

lib/Object/COFFObjectFile.cpp

1277–1278

No, it doesn't:

../lib/Object/COFFObjectFile.cpp:1279:10: error: no match for ‘operator+=’ (operand types are ‘llvm::SmallVectorImpl<char>’ and ‘llvm::StringRef’)

[ruiu]

LGTM

lib/Object/COFFObjectFile.cpp

1179

Remove the trailing backslash.

include/llvm/Object/COFF.h

const coff_load_configuration32 *getLoadConfig32() const {
     assert(!is64());
     return reinterpret_cast<const coff_load_configuration32 *>(LoadConfig);
   }
 
   const coff_load_configuration64 *getLoadConfig64() const {
     assert(is64());
     return reinterpret_cast<const coff_load_configuration64 *>(LoadConfig);
   }
+  StringRef getRelocationTypeName(uint16_t Type) const;
 
 protected:
   void moveSymbolNext(DataRefImpl &Symb) const override;
   Expected<StringRef> getSymbolName(DataRefImpl Symb) const override;
   Expected<uint64_t> getSymbolAddress(DataRefImpl Symb) const override;
   uint32_t getSymbolAlignment(DataRefImpl Symb) const override;
   uint64_t getSymbolValueImpl(DataRefImpl Symb) const override;
   uint64_t getCommonSymbolSizeImpl(DataRefImpl Symb) const override;

lib/Object/COFFObjectFile.cpp

 ArrayRef<coff_relocation>
 COFFObjectFile::getRelocations(const coff_section *Sec) const {
   return {getFirstReloc(Sec, Data, base()),
           getNumberOfRelocations(Sec, Data, base())};
 }
 
 #define LLVM_COFF_SWITCH_RELOC_TYPE_NAME(reloc_type)                           \
   case COFF::reloc_type:                                                       \
-    Res = #reloc_type;                                                         \
-    break;
+    return #reloc_type;                                                         \
 
-void COFFObjectFile::getRelocationTypeName(
-    DataRefImpl Rel, SmallVectorImpl<char> &Result) const {
-  const coff_relocation *Reloc = toRel(Rel);
-  StringRef Res;
+StringRef COFFObjectFile::getRelocationTypeName(uint16_t Type) const {
   switch (getMachine()) {
   case COFF::IMAGE_FILE_MACHINE_AMD64:
-    switch (Reloc->Type) {
+    switch (Type) {
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_ABSOLUTE);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_ADDR64);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_ADDR32);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_ADDR32NB);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_REL32);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_REL32_1);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_REL32_2);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_REL32_3);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_REL32_4);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_REL32_5);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_SECTION);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_SECREL);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_SECREL7);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_TOKEN);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_SREL32);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_PAIR);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_SSPAN32);
     default:
-      Res = "Unknown";
+      return "Unknown";
     }
     break;
   case COFF::IMAGE_FILE_MACHINE_ARMNT:
-    switch (Reloc->Type) {
+    switch (Type) {
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_ABSOLUTE);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_ADDR32);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_ADDR32NB);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_BRANCH24);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_BRANCH11);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_TOKEN);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_BLX24);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_BLX11);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_SECTION);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_SECREL);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_MOV32A);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_MOV32T);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_BRANCH20T);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_BRANCH24T);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_BLX23T);
     default:
-      Res = "Unknown";
+      return "Unknown";
     }
     break;
   case COFF::IMAGE_FILE_MACHINE_ARM64:
-    switch (Reloc->Type) {
+    switch (Type) {
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_ABSOLUTE);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_ADDR32);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_ADDR32NB);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_BRANCH26);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_PAGEBASE_REL21);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_REL21);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_PAGEOFFSET_12A);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_PAGEOFFSET_12L);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_SECREL);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_SECREL_LOW12A);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_SECREL_HIGH12A);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_SECREL_LOW12L);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_TOKEN);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_SECTION);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_ADDR64);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_BRANCH19);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM64_BRANCH14);
     default:
-      Res = "Unknown";
+      return "Unknown";
     }
     break;
   case COFF::IMAGE_FILE_MACHINE_I386:
-    switch (Reloc->Type) {
+    switch (Type) {
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_ABSOLUTE);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_DIR16);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_REL16);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_DIR32);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_DIR32NB);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_SEG12);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_SECTION);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_SECREL);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_TOKEN);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_SECREL7);
     LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_REL32);
     default:
-      Res = "Unknown";
+      return "Unknown";
     }
     break;
   default:
-    Res = "Unknown";
+    return "Unknown";
   }
-  Result.append(Res.begin(), Res.end());
 }
 
 #undef LLVM_COFF_SWITCH_RELOC_TYPE_NAME
 
+void COFFObjectFile::getRelocationTypeName(
+    DataRefImpl Rel, SmallVectorImpl<char> &Result) const {
+  const coff_relocation *Reloc = toRel(Rel);
+  StringRef Res = getRelocationTypeName(Reloc->Type);
+  Result.append(Res.begin(), Res.end());
+}
+
 bool COFFObjectFile::isRelocatableObject() const {
   return !DataDirectory;
 }
 
 bool ImportDirectoryEntryRef::
 operator==(const ImportDirectoryEntryRef &Other) const {
   return ImportTable == Other.ImportTable && Index == Other.Index;
 }