[ELF] Remove needsPltAddr in favor of needsCopy

needsPltAddr is equivalent to `needsCopy && isFunc`. In many places, it is
equivalent to `needsCopy` because the non-STT_FUNC cases are ruled out.

Reviewed By: ikudrin, peter.smith

Differential Revision: https://reviews.llvm.org/D115603

lld/ELF/Arch/AArch64.cpp

@@ -690,11 +690,11 @@ void AArch64BtiPac::writePlt(uint8_t *buf, const Symbol &sym,
   };
   const uint8_t nopData[] = { 0x1f, 0x20, 0x03, 0xd5 }; // nop
 
-  // needsPltAddr indicates a non-ifunc canonical PLT entry whose address may
+  // needsCopy indicates a non-ifunc canonical PLT entry whose address may
   // escape to shared objects. isInIplt indicates a non-preemptible ifunc. Its
   // address may escape if referenced by a direct relocation. The condition is
   // conservative.
-  bool hasBti = btiHeader && (sym.needsPltAddr || sym.isInIplt);
+  bool hasBti = btiHeader && (sym.needsCopy || sym.isInIplt);
   if (hasBti) {
     memcpy(buf, btiData, sizeof(btiData));
     buf += sizeof(btiData);

lld/ELF/MapFile.cpp

@@ -58,7 +58,7 @@ static std::vector<Defined *> getSymbols() {
     for (Symbol *b : file->getSymbols())
       if (auto *dr = dyn_cast<Defined>(b))
         if (!dr->isSection() && dr->section && dr->section->isLive() &&
-            (dr->file == file || dr->needsPltAddr || dr->section->bss))
+            (dr->file == file || dr->needsCopy || dr->section->bss))
           v.push_back(dr);
   return v;
 }

lld/ELF/Relocations.cpp

@@ -1626,14 +1626,14 @@ void elf::postScanRelocations() {
           replaceWithDefined(
               sym, in.plt,
               target->pltHeaderSize + target->pltEntrySize * sym.pltIndex, 0);
+          sym.needsCopy = true;
           if (config->emachine == EM_PPC) {
             // PPC32 canonical PLT entries are at the beginning of .glink
             cast<Defined>(sym).value = in.plt->headerSize;
             in.plt->headerSize += 16;
             cast<PPC32GlinkSection>(in.plt)->canonical_plts.push_back(&sym);
           }
         }
-        sym.needsPltAddr = true;
       }
     }
   };

lld/ELF/Symbols.cpp

@@ -120,7 +120,7 @@ static uint64_t getSymVA(const Symbol &sym, int64_t addend) {
     // field etc) do the same trick as compiler uses to mark microMIPS
     // for CPU - set the less-significant bit.
     if (config->emachine == EM_MIPS && isMicroMips() &&
-        ((sym.stOther & STO_MIPS_MICROMIPS) || sym.needsPltAddr))
+        ((sym.stOther & STO_MIPS_MICROMIPS) || sym.needsCopy))
       va |= 1;
 
     if (d.isTls() && !config->relocatable) {

lld/ELF/Symbols.h

@@ -245,17 +245,12 @@ class Symbol {
         type(type), stOther(stOther), symbolKind(k), visibility(stOther & 3),
         isUsedInRegularObj(!file || file->kind() == InputFile::ObjKind),
         exportDynamic(isExportDynamic(k, visibility)), inDynamicList(false),
-        canInline(false), referenced(false), traced(false), needsPltAddr(false),
-        isInIplt(false), gotInIgot(false), isPreemptible(false),
-        used(!config->gcSections), needsTocRestore(false), scriptDefined(false),
-        needsCopy(false), needsGot(false), needsPlt(false),
-        hasDirectReloc(false) {}
+        canInline(false), referenced(false), traced(false), isInIplt(false),
+        gotInIgot(false), isPreemptible(false), used(!config->gcSections),
+        needsTocRestore(false), scriptDefined(false), needsCopy(false),
+        needsGot(false), needsPlt(false), hasDirectReloc(false) {}
 
 public:
-  // True the symbol should point to its PLT entry.
-  // For SharedSymbol only.
-  uint8_t needsPltAddr : 1;
-
   // True if this symbol is in the Iplt sub-section of the Plt and the Igot
   // sub-section of the .got.plt or .got.
   uint8_t isInIplt : 1;

lld/ELF/SyntheticSections.cpp

@@ -2175,7 +2175,8 @@ static BssSection *getCommonSec(Symbol *sym) {
 static uint32_t getSymSectionIndex(Symbol *sym) {
   if (getCommonSec(sym))
     return SHN_COMMON;
-  if (!isa<Defined>(sym) || sym->needsPltAddr)
+  assert(!(sym->needsCopy && sym->isObject()));
+  if (!isa<Defined>(sym) || sym->needsCopy)
     return SHN_UNDEF;
   if (const OutputSection *os = sym->getOutputSection())
     return os->sectionIndex >= SHN_LORESERVE ? (uint32_t)SHN_XINDEX
@@ -2250,7 +2251,7 @@ template <class ELFT> void SymbolTableSection<ELFT>::writeTo(uint8_t *buf) {
 
     for (SymbolTableEntry &ent : symbols) {
       Symbol *sym = ent.sym;
-      if (sym->isInPlt() && sym->needsPltAddr)
+      if (sym->isInPlt() && sym->needsCopy)
         eSym->st_other |= STO_MIPS_PLT;
       if (isMicroMips()) {
         // We already set the less-significant bit for symbols
@@ -2261,7 +2262,7 @@ template <class ELFT> void SymbolTableSection<ELFT>::writeTo(uint8_t *buf) {
         // like `objdump` will be able to deal with a correct
         // symbol position.
         if (sym->isDefined() &&
-            ((sym->stOther & STO_MIPS_MICROMIPS) || sym->needsPltAddr)) {
+            ((sym->stOther & STO_MIPS_MICROMIPS) || sym->needsCopy)) {
           if (!strTabSec.isDynamic())
             eSym->st_value &= ~1;
           eSym->st_other |= STO_MIPS_MICROMIPS;