fix PR5673 by being more careful about pointers to functions.

llvm-svn: 90369

lib/Analysis/ConstantFolding.cpp

@@ -569,9 +569,16 @@ static Constant *SymbolicallyEvaluateGEP(Constant *const *Ops, unsigned NumOps,
   SmallVector<Constant*, 32> NewIdxs;
   do {
     if (const SequentialType *ATy = dyn_cast<SequentialType>(Ty)) {
-      // The only pointer indexing we'll do is on the first index of the GEP.
-      if (isa<PointerType>(ATy) && !NewIdxs.empty())
-        break;
+      if (isa<PointerType>(ATy)) {
+        // The only pointer indexing we'll do is on the first index of the GEP.
+        if (!NewIdxs.empty())
+          break;
+       
+        // Only handle pointers to sized types, not pointers to functions.
+        if (!ATy->getElementType()->isSized())
+          return 0;
+      }
+        
       // Determine which element of the array the offset points into.
       APInt ElemSize(BitWidth, TD->getTypeAllocSize(ATy->getElementType()));
       if (ElemSize == 0)

test/Transforms/InstCombine/crash.ll

@@ -137,3 +137,14 @@ define arm_apcscc void @test5() {
 exit:
        ret void
 }
+
+
+; PR5673
+
+@test6g = external global i32*  
+
+define arm_aapcs_vfpcc i32 @test6(i32 %argc, i8** %argv) nounwind {
+entry:
+  store i32* getelementptr (i32* bitcast (i32 (i32, i8**)* @test6 to i32*), i32 -2048), i32** @test6g, align 4
+  unreachable
+}