[NFC] [lld] [MTE] Rename MemtagDescriptors to MemtagGlobalDescriptors (#77300)

Requested in #77078, I agree
that we may as well be unambiguous.

Author: hctim

lld/ELF/Relocations.cpp

@@ -1669,7 +1669,7 @@ void elf::postScanRelocations() {
       return;
 
     if (sym.isTagged() && sym.isDefined())
-      mainPart->memtagDescriptors->addSymbol(sym);
+      mainPart->memtagGlobalDescriptors->addSymbol(sym);
 
     if (!sym.needsDynReloc())
       return;

lld/ELF/SyntheticSections.cpp

@@ -1454,9 +1454,10 @@ DynamicSection<ELFT>::computeContents() {
       addInt(DT_AARCH64_MEMTAG_MODE, config->androidMemtagMode == NT_MEMTAG_LEVEL_ASYNC);
       addInt(DT_AARCH64_MEMTAG_HEAP, config->androidMemtagHeap);
       addInt(DT_AARCH64_MEMTAG_STACK, config->androidMemtagStack);
-      if (mainPart->memtagDescriptors->isNeeded()) {
-        addInSec(DT_AARCH64_MEMTAG_GLOBALS, *mainPart->memtagDescriptors);
-        addInt(DT_AARCH64_MEMTAG_GLOBALSSZ, mainPart->memtagDescriptors->getSize());
+      if (mainPart->memtagGlobalDescriptors->isNeeded()) {
+        addInSec(DT_AARCH64_MEMTAG_GLOBALS, *mainPart->memtagGlobalDescriptors);
+        addInt(DT_AARCH64_MEMTAG_GLOBALSSZ,
+               mainPart->memtagGlobalDescriptors->getSize());
       }
     }
   }
@@ -3919,8 +3920,9 @@ static size_t computeOrWriteULEB128(uint64_t v, uint8_t *buf, size_t offset) {
 // https://github.com/ARM-software/abi-aa/blob/main/memtagabielf64/memtagabielf64.rst#83encoding-of-sht_aarch64_memtag_globals_dynamic
 constexpr uint64_t kMemtagStepSizeBits = 3;
 constexpr uint64_t kMemtagGranuleSize = 16;
-static size_t createMemtagDescriptors(const SmallVector<const Symbol *, 0> &symbols,
-                                      uint8_t *buf = nullptr) {
+static size_t
+createMemtagGlobalDescriptors(const SmallVector<const Symbol *, 0> &symbols,
+                              uint8_t *buf = nullptr) {
   size_t sectionSize = 0;
   uint64_t lastGlobalEnd = 0;
 
@@ -3961,7 +3963,7 @@ static size_t createMemtagDescriptors(const SmallVector<const Symbol *, 0> &symb
   return sectionSize;
 }
 
-bool MemtagDescriptors::updateAllocSize() {
+bool MemtagGlobalDescriptors::updateAllocSize() {
   size_t oldSize = getSize();
   std::stable_sort(symbols.begin(), symbols.end(),
                    [](const Symbol *s1, const Symbol *s2) {
@@ -3970,12 +3972,12 @@ bool MemtagDescriptors::updateAllocSize() {
   return oldSize != getSize();
 }
 
-void MemtagDescriptors::writeTo(uint8_t *buf) {
-  createMemtagDescriptors(symbols, buf);
+void MemtagGlobalDescriptors::writeTo(uint8_t *buf) {
+  createMemtagGlobalDescriptors(symbols, buf);
 }
 
-size_t MemtagDescriptors::getSize() const {
-  return createMemtagDescriptors(symbols);
+size_t MemtagGlobalDescriptors::getSize() const {
+  return createMemtagGlobalDescriptors(symbols);
 }
 
 InStruct elf::in;

lld/ELF/SyntheticSections.h

@@ -1257,9 +1257,9 @@ class PackageMetadataNote final : public SyntheticSection {
   size_t getSize() const override;
 };
 
-class MemtagDescriptors final : public SyntheticSection {
+class MemtagGlobalDescriptors final : public SyntheticSection {
 public:
-  MemtagDescriptors()
+  MemtagGlobalDescriptors()
       : SyntheticSection(llvm::ELF::SHF_ALLOC,
                          llvm::ELF::SHT_AARCH64_MEMTAG_GLOBALS_DYNAMIC,
                          /*alignment=*/4, ".memtag.globals.dynamic") {}
@@ -1315,7 +1315,7 @@ struct Partition {
   std::unique_ptr<GnuHashTableSection> gnuHashTab;
   std::unique_ptr<HashTableSection> hashTab;
   std::unique_ptr<MemtagAndroidNote> memtagAndroidNote;
-  std::unique_ptr<MemtagDescriptors> memtagDescriptors;
+  std::unique_ptr<MemtagGlobalDescriptors> memtagGlobalDescriptors;
   std::unique_ptr<PackageMetadataNote> packageMetadataNote;
   std::unique_ptr<RelocationBaseSection> relaDyn;
   std::unique_ptr<RelrBaseSection> relrDyn;

lld/ELF/Writer.cpp

@@ -405,8 +405,9 @@ template <class ELFT> void elf::createSyntheticSections() {
       part.memtagAndroidNote = std::make_unique<MemtagAndroidNote>();
       add(*part.memtagAndroidNote);
       if (canHaveMemtagGlobals()) {
-        part.memtagDescriptors = std::make_unique<MemtagDescriptors>();
-        add(*part.memtagDescriptors);
+        part.memtagGlobalDescriptors =
+            std::make_unique<MemtagGlobalDescriptors>();
+        add(*part.memtagGlobalDescriptors);
       }
     }
 
@@ -1731,8 +1732,8 @@ template <class ELFT> void Writer<ELFT>::finalizeAddressDependentContent() {
       changed |= part.relaDyn->updateAllocSize();
       if (part.relrDyn)
         changed |= part.relrDyn->updateAllocSize();
-      if (part.memtagDescriptors)
-        changed |= part.memtagDescriptors->updateAllocSize();
+      if (part.memtagGlobalDescriptors)
+        changed |= part.memtagGlobalDescriptors->updateAllocSize();
     }
 
     const Defined *changedSym = script->assignAddresses();