Move ARM-specific MCSymbolRefExpr::VariantKind to ARMMCExpr::Specifier

Similar to previous migration done for other targets (PowerPC, X86,
etc).

Note: ARMELFObjectWriter::needsRelocateWithSymbol is conservative and
already includes most specifiers.

Author: MaskRay

llvm/include/llvm/MC/MCExpr.h

@@ -220,21 +220,6 @@ class MCSymbolRefExpr : public MCExpr {
     VK_GOTPAGEOFF,
     VK_SECREL,
     VK_WEAKREF, // The link between the symbols in .weakref foo, bar
-    VK_FUNCDESC,
-    VK_GOTFUNCDESC,
-    VK_GOTOFFFUNCDESC,
-    VK_TLSGD_FDPIC,
-    VK_TLSLDM_FDPIC,
-    VK_GOTTPOFF_FDPIC,
-
-    VK_ARM_NONE,
-    VK_ARM_GOT_PREL,
-    VK_ARM_TARGET1,
-    VK_ARM_TARGET2,
-    VK_ARM_PREL31,
-    VK_ARM_SBREL,  // symbol(sbrel)
-    VK_ARM_TLSLDO, // symbol(tlsldo)
-    VK_ARM_TLSDESCSEQ,
 
     VK_COFF_IMGREL32, // symbol@imgrel (image-relative)
 

llvm/lib/Target/ARM/ARMAsmPrinter.cpp

@@ -90,12 +90,10 @@ void ARMAsmPrinter::emitXXStructor(const DataLayout &DL, const Constant *CV) {
   const GlobalValue *GV = dyn_cast<GlobalValue>(CV->stripPointerCasts());
   assert(GV && "C++ constructor pointer was not a GlobalValue!");
 
-  const MCExpr *E = MCSymbolRefExpr::create(GetARMGVSymbol(GV,
-                                                           ARMII::MO_NO_FLAG),
-                                            (Subtarget->isTargetELF()
-                                             ? MCSymbolRefExpr::VK_ARM_TARGET1
-                                             : MCSymbolRefExpr::VK_None),
-                                            OutContext);
+  const MCExpr *E = MCSymbolRefExpr::create(
+      GetARMGVSymbol(GV, ARMII::MO_NO_FLAG),
+      (Subtarget->isTargetELF() ? ARMMCExpr::VK_TARGET1 : ARMMCExpr::VK_None),
+      OutContext);
 
   OutStreamer->emitValue(E, Size);
 }
@@ -835,21 +833,20 @@ static MCSymbol *getPICLabel(StringRef Prefix, unsigned FunctionNumber,
   return Label;
 }
 
-static MCSymbolRefExpr::VariantKind
-getModifierVariantKind(ARMCP::ARMCPModifier Modifier) {
+static uint8_t getModifierSpecifier(ARMCP::ARMCPModifier Modifier) {
   switch (Modifier) {
   case ARMCP::no_modifier:
-    return MCSymbolRefExpr::VK_None;
+    return ARMMCExpr::VK_None;
   case ARMCP::TLSGD:
-    return MCSymbolRefExpr::VK_TLSGD;
+    return ARMMCExpr::VK_TLSGD;
   case ARMCP::TPOFF:
-    return MCSymbolRefExpr::VK_TPOFF;
+    return ARMMCExpr::VK_TPOFF;
   case ARMCP::GOTTPOFF:
-    return MCSymbolRefExpr::VK_GOTTPOFF;
+    return ARMMCExpr::VK_GOTTPOFF;
   case ARMCP::SBREL:
-    return MCSymbolRefExpr::VK_ARM_SBREL;
+    return ARMMCExpr::VK_SBREL;
   case ARMCP::GOT_PREL:
-    return MCSymbolRefExpr::VK_ARM_GOT_PREL;
+    return ARMMCExpr::VK_GOT_PREL;
   case ARMCP::SECREL:
     return MCSymbolRefExpr::VK_SECREL;
   }
@@ -964,9 +961,8 @@ void ARMAsmPrinter::emitMachineConstantPoolValue(
   }
 
   // Create an MCSymbol for the reference.
-  const MCExpr *Expr =
-    MCSymbolRefExpr::create(MCSym, getModifierVariantKind(ACPV->getModifier()),
-                            OutContext);
+  const MCExpr *Expr = MCSymbolRefExpr::create(
+      MCSym, getModifierSpecifier(ACPV->getModifier()), OutContext);
 
   if (ACPV->getPCAdjustment()) {
     MCSymbol *PCLabel =

llvm/lib/Target/ARM/ARMMCInstLower.cpp

@@ -37,9 +37,9 @@ using namespace llvm;
 
 MCOperand ARMAsmPrinter::GetSymbolRef(const MachineOperand &MO,
                                       const MCSymbol *Symbol) {
-  MCSymbolRefExpr::VariantKind Specifier = MCSymbolRefExpr::VK_None;
+  auto Specifier = ARMMCExpr::VK_None;
   if (MO.getTargetFlags() & ARMII::MO_SBREL)
-    Specifier = MCSymbolRefExpr::VK_ARM_SBREL;
+    Specifier = ARMMCExpr::VK_SBREL;
 
   const MCExpr *Expr = MCSymbolRefExpr::create(Symbol, Specifier, OutContext);
   switch (MO.getTargetFlags() & ARMII::MO_OPTION_MASK) {

llvm/lib/Target/ARM/ARMTargetObjectFile.cpp

@@ -9,6 +9,7 @@
 #include "ARMTargetObjectFile.h"
 #include "ARMSubtarget.h"
 #include "ARMTargetMachine.h"
+#include "MCTargetDesc/ARMMCExpr.h"
 #include "llvm/BinaryFormat/Dwarf.h"
 #include "llvm/BinaryFormat/ELF.h"
 #include "llvm/MC/MCAsmInfo.h"
@@ -29,7 +30,7 @@ using namespace dwarf;
 //===----------------------------------------------------------------------===//
 
 ARMElfTargetObjectFile::ARMElfTargetObjectFile() {
-  PLTRelativeSpecifier = MCSymbolRefExpr::VK_ARM_PREL31;
+  PLTRelativeSpecifier = ARMMCExpr::VK_PREL31;
   SupportIndirectSymViaGOTPCRel = true;
 }
 
@@ -66,16 +67,15 @@ const MCExpr *ARMElfTargetObjectFile::getIndirectSymViaGOTPCRel(
     const GlobalValue *GV, const MCSymbol *Sym, const MCValue &MV,
     int64_t Offset, MachineModuleInfo *MMI, MCStreamer &Streamer) const {
   int64_t FinalOffset = Offset + MV.getConstant();
-  const MCExpr *Res = MCSymbolRefExpr::create(
-      Sym, MCSymbolRefExpr::VK_ARM_GOT_PREL, getContext());
+  const MCExpr *Res =
+      MCSymbolRefExpr::create(Sym, ARMMCExpr::VK_GOT_PREL, getContext());
   const MCExpr *Off = MCConstantExpr::create(FinalOffset, getContext());
   return MCBinaryExpr::createAdd(Res, Off, getContext());
 }
 
 const MCExpr *ARMElfTargetObjectFile::
 getIndirectSymViaRWPI(const MCSymbol *Sym) const {
-  return MCSymbolRefExpr::create(Sym, MCSymbolRefExpr::VK_ARM_SBREL,
-                                 getContext());
+  return MCSymbolRefExpr::create(Sym, ARMMCExpr::VK_SBREL, getContext());
 }
 
 const MCExpr *ARMElfTargetObjectFile::getTTypeGlobalReference(
@@ -87,14 +87,13 @@ const MCExpr *ARMElfTargetObjectFile::getTTypeGlobalReference(
 
   assert(Encoding == DW_EH_PE_absptr && "Can handle absptr encoding only");
 
-  return MCSymbolRefExpr::create(TM.getSymbol(GV),
-                                 MCSymbolRefExpr::VK_ARM_TARGET2, getContext());
+  return MCSymbolRefExpr::create(TM.getSymbol(GV), ARMMCExpr::VK_TARGET2,
+                                 getContext());
 }
 
 const MCExpr *ARMElfTargetObjectFile::
 getDebugThreadLocalSymbol(const MCSymbol *Sym) const {
-  return MCSymbolRefExpr::create(Sym, MCSymbolRefExpr::VK_ARM_TLSLDO,
-                                 getContext());
+  return MCSymbolRefExpr::create(Sym, ARMMCExpr::VK_TLSLDO, getContext());
 }
 
 static bool isExecuteOnlyFunction(const GlobalObject *GO, SectionKind SK,

llvm/lib/Target/ARM/AsmParser/ARMAsmParser.cpp

@@ -12437,8 +12437,8 @@ bool ARMAsmParser::parseDirectiveTLSDescSeq(SMLoc L) {
     return TokError("expected variable after '.tlsdescseq' directive");
 
   auto *Sym = getContext().getOrCreateSymbol(Parser.getTok().getIdentifier());
-  const auto *SRE = MCSymbolRefExpr::create(
-      Sym, MCSymbolRefExpr::VK_ARM_TLSDESCSEQ, getContext());
+  const auto *SRE =
+      MCSymbolRefExpr::create(Sym, ARMMCExpr::VK_TLSDESCSEQ, getContext());
   Lex();
 
   if (parseEOL())

llvm/lib/Target/ARM/MCTargetDesc/ARMAsmBackend.cpp

@@ -12,6 +12,7 @@
 #include "MCTargetDesc/ARMAsmBackendELF.h"
 #include "MCTargetDesc/ARMAsmBackendWinCOFF.h"
 #include "MCTargetDesc/ARMFixupKinds.h"
+#include "MCTargetDesc/ARMMCExpr.h"
 #include "MCTargetDesc/ARMMCTargetDesc.h"
 #include "llvm/ADT/StringSwitch.h"
 #include "llvm/BinaryFormat/ELF.h"
@@ -605,7 +606,7 @@ unsigned ARMAsmBackend::adjustFixupValue(const MCAssembler &Asm,
     // Offset by 8 just as above.
     if (const MCSymbolRefExpr *SRE =
             dyn_cast<MCSymbolRefExpr>(Fixup.getValue()))
-      if (SRE->getKind() == MCSymbolRefExpr::VK_TLSCALL)
+      if (getSpecifier(SRE) == ARMMCExpr::VK_TLSCALL)
         return 0;
     return 0xffffff & (Value >> 2);
   case ARM::fixup_t2_uncondbranch: {
@@ -732,7 +733,7 @@ unsigned ARMAsmBackend::adjustFixupValue(const MCAssembler &Asm,
     uint32_t offset = (Value - 4) >> 2;
     if (const MCSymbolRefExpr *SRE =
             dyn_cast<MCSymbolRefExpr>(Fixup.getValue()))
-      if (SRE->getKind() == MCSymbolRefExpr::VK_TLSCALL)
+      if (getSpecifier(SRE) == ARMMCExpr::VK_TLSCALL)
         offset = 0;
     uint32_t signBit = (offset & 0x400000) >> 22;
     uint32_t I1Bit = (offset & 0x200000) >> 21;