Clean up and improve tests

Author: djtodoro

llvm/lib/Target/Mips/MipsISelLowering.cpp

@@ -3408,15 +3408,13 @@ MipsTargetLowering::LowerCall(TargetLowering::CallLoweringInfo &CLI,
   // For non-musttail calls, restrict to functions that won't require $gp
   // restoration. In PIC mode, calling external functions via tail call can
   // cause issues with $gp register handling (see D24763).
-  bool InternalLinkage = false;
   bool IsMustTail = CLI.CB && CLI.CB->isMustTailCall();
   if (IsTailCall) {
     IsTailCall = isEligibleForTailCallOptimization(
         CCInfo, StackSize, *MF.getInfo<MipsFunctionInfo>(), IsMustTail);
     // For non-musttail calls, restrict to local or non-interposable functions
     if (IsTailCall && !IsMustTail) {
       if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee)) {
-        InternalLinkage = G->getGlobal()->hasInternalLinkage();
         IsTailCall &= (G->getGlobal()->hasLocalLinkage() ||
                        G->getGlobal()->hasHiddenVisibility() ||
                        G->getGlobal()->hasProtectedVisibility());
@@ -3600,6 +3598,7 @@ MipsTargetLowering::LowerCall(TargetLowering::CallLoweringInfo &CLI,
     }
   }
 
+  bool InternalLinkage = false;
   if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee)) {
     if (Subtarget.isTargetCOFF() &&
         G->getGlobal()->hasDLLImportStorageClass()) {

llvm/lib/Target/Mips/MipsSEISelLowering.h

@@ -63,9 +63,10 @@ class TargetRegisterClass;
     const TargetRegisterClass *getRepRegClassFor(MVT VT) const override;
 
   private:
-    bool isEligibleForTailCallOptimization(
-        const CCState &CCInfo, unsigned NextStackOffset,
-        const MipsFunctionInfo &FI, bool IsMustTail) const override;
+    bool isEligibleForTailCallOptimization(const CCState &CCInfo,
+                                           unsigned NextStackOffset,
+                                           const MipsFunctionInfo &FI,
+                                           bool IsMustTail) const override;
 
     void
     getOpndList(SmallVectorImpl<SDValue> &Ops,

llvm/test/CodeGen/Mips/musttail.ll

@@ -95,3 +95,20 @@ define float @test_musttail_mixed_args(i32 %a, float %b, i32 %c, float %d, i32 %
   %ret = musttail call float @mixed_args_callee(i32 %a, float %b, i32 %c, float %d, i32 %e, float %f)
   ret float %ret
 }
+
+; Test musttail with indirect call
+define i32 @test_musttail_fptr(ptr %fptr, i32 %x) {
+; MIPS32-LABEL: test_musttail_fptr:
+; MIPS32:       # %bb.0:
+; MIPS32-NEXT:    move $25, $4
+; MIPS32-NEXT:    jr $25
+; MIPS32-NEXT:    nop
+;
+; MIPS64-LABEL: test_musttail_fptr:
+; MIPS64:       # %bb.0:
+; MIPS64-NEXT:    move $25, $4
+; MIPS64-NEXT:    jr $25
+; MIPS64-NEXT:    nop
+  %ret = musttail call i32 %fptr(ptr %fptr, i32 %x)
+  ret i32 %ret
+}