Revert "[X86] Use 64-bit jump table entries for large code model PIC"

This reverts commit 2a2f02e.

Author: Zentrik

llvm/include/llvm/CodeGen/MIRYamlMapping.h

@@ -137,8 +137,6 @@ template <> struct ScalarEnumerationTraits<MachineJumpTableInfo::JTEntryKind> {
                 MachineJumpTableInfo::EK_GPRel32BlockAddress);
     IO.enumCase(EntryKind, "label-difference32",
                 MachineJumpTableInfo::EK_LabelDifference32);
-    IO.enumCase(EntryKind, "label-difference64",
-                MachineJumpTableInfo::EK_LabelDifference64);
     IO.enumCase(EntryKind, "inline", MachineJumpTableInfo::EK_Inline);
     IO.enumCase(EntryKind, "custom32", MachineJumpTableInfo::EK_Custom32);
   }

llvm/include/llvm/CodeGen/MachineJumpTableInfo.h

@@ -67,12 +67,6 @@ class MachineJumpTableInfo {
     ///      .word L4_5_set_123
     EK_LabelDifference32,
 
-    /// EK_LabelDifference64 - Each entry is the address of the block minus
-    /// the address of the jump table.  This is used for PIC jump tables where
-    /// gprel64 is not supported.  e.g.:
-    ///      .quad LBB123 - LJTI1_2
-    EK_LabelDifference64,
-
     /// EK_Inline - Jump table entries are emitted inline at their point of
     /// use. It is the responsibility of the target to emit the entries.
     EK_Inline,
@@ -81,7 +75,6 @@ class MachineJumpTableInfo {
     /// TargetLowering::LowerCustomJumpTableEntry hook.
     EK_Custom32
   };
-
 private:
   JTEntryKind EntryKind;
   std::vector<MachineJumpTableEntry> JumpTables;

llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp

@@ -2698,8 +2698,7 @@ void AsmPrinter::emitJumpTableInfo() {
   const Function &F = MF->getFunction();
   const TargetLoweringObjectFile &TLOF = getObjFileLowering();
   bool JTInDiffSection = !TLOF.shouldPutJumpTableInFunctionSection(
-      MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 ||
-          MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference64,
+      MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32,
       F);
   if (JTInDiffSection) {
     // Drop it in the readonly section.
@@ -2797,17 +2796,15 @@ void AsmPrinter::emitJumpTableEntry(const MachineJumpTableInfo *MJTI,
     return;
   }
 
-  case MachineJumpTableInfo::EK_LabelDifference32:
-  case MachineJumpTableInfo::EK_LabelDifference64: {
+  case MachineJumpTableInfo::EK_LabelDifference32: {
     // Each entry is the address of the block minus the address of the jump
     // table. This is used for PIC jump tables where gprel32 is not supported.
     // e.g.:
     //      .word LBB123 - LJTI1_2
     // If the .set directive avoids relocations, this is emitted as:
     //      .set L4_5_set_123, LBB123 - LJTI1_2
     //      .word L4_5_set_123
-    if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 &&
-        MAI->doesSetDirectiveSuppressReloc()) {
+    if (MAI->doesSetDirectiveSuppressReloc()) {
       Value = MCSymbolRefExpr::create(GetJTSetSymbol(UID, MBB->getNumber()),
                                       OutContext);
       break;

llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp

@@ -3554,7 +3554,6 @@ void CodeViewDebug::collectDebugInfoForJumpTables(const MachineFunction *MF,
           break;
         case MachineJumpTableInfo::EK_Inline:
         case MachineJumpTableInfo::EK_LabelDifference32:
-        case MachineJumpTableInfo::EK_LabelDifference64:
           // Ask the AsmPrinter.
           std::tie(Base, BaseOffset, Branch, EntrySize) =
               Asm->getCodeViewJumpTableInfo(JumpTableIndex, &BranchMI, Branch);

llvm/lib/CodeGen/MachineFunction.cpp

@@ -1252,7 +1252,6 @@ unsigned MachineJumpTableInfo::getEntrySize(const DataLayout &TD) const {
   case MachineJumpTableInfo::EK_BlockAddress:
     return TD.getPointerSize();
   case MachineJumpTableInfo::EK_GPRel64BlockAddress:
-  case MachineJumpTableInfo::EK_LabelDifference64:
     return 8;
   case MachineJumpTableInfo::EK_GPRel32BlockAddress:
   case MachineJumpTableInfo::EK_LabelDifference32:
@@ -1273,7 +1272,6 @@ unsigned MachineJumpTableInfo::getEntryAlignment(const DataLayout &TD) const {
   case MachineJumpTableInfo::EK_BlockAddress:
     return TD.getPointerABIAlignment(0).value();
   case MachineJumpTableInfo::EK_GPRel64BlockAddress:
-  case MachineJumpTableInfo::EK_LabelDifference64:
     return TD.getABIIntegerTypeAlignment(64).value();
   case MachineJumpTableInfo::EK_GPRel32BlockAddress:
   case MachineJumpTableInfo::EK_LabelDifference32:

llvm/lib/Target/X86/X86ISelLoweringCall.cpp

@@ -416,9 +416,6 @@ unsigned X86TargetLowering::getJumpTableEncoding() const {
   // symbol.
   if (isPositionIndependent() && Subtarget.isPICStyleGOT())
     return MachineJumpTableInfo::EK_Custom32;
-  if (isPositionIndependent() &&
-      getTargetMachine().getCodeModel() == CodeModel::Large)
-    return MachineJumpTableInfo::EK_LabelDifference64;
 
   // Otherwise, use the normal jump table encoding heuristics.
   return TargetLowering::getJumpTableEncoding();
@@ -484,9 +481,7 @@ const MCExpr *X86TargetLowering::
 getPICJumpTableRelocBaseExpr(const MachineFunction *MF, unsigned JTI,
                              MCContext &Ctx) const {
   // X86-64 uses RIP relative addressing based on the jump table label.
-  if (Subtarget.isPICStyleRIPRel() ||
-      (Subtarget.is64Bit() &&
-       getTargetMachine().getCodeModel() == CodeModel::Large))
+  if (Subtarget.isPICStyleRIPRel())
     return TargetLowering::getPICJumpTableRelocBaseExpr(MF, JTI, Ctx);
 
   // Otherwise, the reference is relative to the PIC base.