eliminate the TargetLowering::UsesGlobalOffsetTable bool, which is

subsumed by TargetLowering::getJumpTableEncoding().  Change uses of
it to be more specific.

llvm-svn: 94529

llvm/include/llvm/Target/TargetLowering.h

@@ -118,10 +118,6 @@ public:
   MVT getPointerTy() const { return PointerTy; }
   MVT getShiftAmountTy() const { return ShiftAmountTy; }
 
-  /// usesGlobalOffsetTable - Return true if this target uses a GOT for PIC
-  /// codegen.
-  bool usesGlobalOffsetTable() const { return UsesGlobalOffsetTable; }
-
   /// isSelectExpensive - Return true if the select operation is expensive for
   /// this target.
   bool isSelectExpensive() const { return SelectIsExpensive; }
@@ -908,10 +904,6 @@ public:
   //
 
 protected:
-  /// setUsesGlobalOffsetTable - Specify that this target does or doesn't use a
-  /// GOT for PC-relative code.
-  void setUsesGlobalOffsetTable(bool V) { UsesGlobalOffsetTable = V; }
-
   /// setShiftAmountType - Describe the type that should be used for shift
   /// amounts.  This type defaults to the pointer type.
   void setShiftAmountType(MVT VT) { ShiftAmountTy = VT; }
@@ -1594,10 +1586,6 @@ private:
   ///
   bool IsLittleEndian;
 
-  /// UsesGlobalOffsetTable - True if this target uses a GOT for PIC codegen.
-  ///
-  bool UsesGlobalOffsetTable;
-  
   /// SelectIsExpensive - Tells the code generator not to expand operations
   /// into sequences that use the select operations if possible.
   bool SelectIsExpensive;

llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp

@@ -481,18 +481,19 @@ void AsmPrinter::EmitJumpTableInfo(MachineFunction &MF) {
   const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
   if (JT.empty()) return;
 
-  bool IsPic = TM.getRelocationModel() == Reloc::PIC_;
-  
   // Pick the directive to use to print the jump table entries, and switch to 
   // the appropriate section.
   const Function *F = MF.getFunction();
   bool JTInDiffSection = false;
-  if (F->isWeakForLinker() ||
-      (IsPic && !TM.getTargetLowering()->usesGlobalOffsetTable())) {
-    // In PIC mode, we need to emit the jump table to the same section as the
-    // function body itself, otherwise the label differences won't make sense.
-    // We should also do if the section name is NULL or function is declared in
-    // discardable section.
+  if (// In PIC mode, we need to emit the jump table to the same section as the
+      // function body itself, otherwise the label differences won't make sense.
+      // FIXME: Need a better predicate for this: what about custom entries?
+      MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 ||
+      // We should also do if the section name is NULL or function is declared
+      // in discardable section
+      // FIXME: this isn't the right predicate, should be based on the MCSection
+      // for the function.
+      F->isWeakForLinker()) {
     OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F, Mang,
                                                                     TM));
   } else {

llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp

@@ -510,7 +510,6 @@ TargetLowering::TargetLowering(TargetMachine &tm,TargetLoweringObjectFile *tlof)
   setOperationAction(ISD::TRAP, MVT::Other, Expand);
     
   IsLittleEndian = TD->isLittleEndian();
-  UsesGlobalOffsetTable = false;
   ShiftAmountTy = PointerTy = MVT::getIntegerVT(8*TD->getPointerSize());
   memset(RegClassForVT, 0,MVT::LAST_VALUETYPE*sizeof(TargetRegisterClass*));
   memset(TargetDAGCombineArray, 0, array_lengthof(TargetDAGCombineArray));
@@ -814,8 +813,8 @@ unsigned TargetLowering::getJumpTableEncoding() const {
 
 SDValue TargetLowering::getPICJumpTableRelocBase(SDValue Table,
                                                  SelectionDAG &DAG) const {
-  // FIXME: Eliminate usesGlobalOffsetTable() in favor of JTEntryKind.
-  if (usesGlobalOffsetTable())
+  // If our PIC model is GP relative, use the global offset table as the base.
+  if (getJumpTableEncoding() == MachineJumpTableInfo::EK_GPRel32BlockAddress)
     return DAG.getGLOBAL_OFFSET_TABLE(getPointerTy());
   return Table;
 }

llvm/lib/Target/Alpha/AlphaISelLowering.cpp

@@ -49,8 +49,6 @@ AlphaTargetLowering::AlphaTargetLowering(TargetMachine &TM)
   setShiftAmountType(MVT::i64);
   setBooleanContents(ZeroOrOneBooleanContent);
 
-  setUsesGlobalOffsetTable(true);
-
   addRegisterClass(MVT::i64, Alpha::GPRCRegisterClass);
   addRegisterClass(MVT::f64, Alpha::F8RCRegisterClass);
   addRegisterClass(MVT::f32, Alpha::F4RCRegisterClass);

llvm/lib/Target/Mips/MipsISelLowering.cpp

@@ -60,9 +60,6 @@ MipsTargetLowering(MipsTargetMachine &TM)
   // setcc operations results (slt, sgt, ...). 
   setBooleanContents(ZeroOrOneBooleanContent);
 
-  // JumpTable targets must use GOT when using PIC_
-  setUsesGlobalOffsetTable(true);
-
   // Set up the register classes
   addRegisterClass(MVT::i32, Mips::CPURegsRegisterClass);
   addRegisterClass(MVT::f32, Mips::FGR32RegisterClass);