Fix PR3468: a crash when constant folding a bitcast of

i80 to x86 long double (this was presumably generated
by sroa).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63730 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 12 insertions, 6 deletions

diff --git a/lib/VMCore/ConstantFold.cpp b/lib/VMCore/ConstantFold.cpp
index 5c1578f74b..5f7cbcd0b6 100644
--- a/lib/VMCore/ConstantFold.cpp
+++ b/lib/VMCore/ConstantFold.cpp
@@ -153,12 +153,11 @@ static Constant *FoldBitCast(Constant *V, const Type *DestTy) {
       // Integral -> Integral. This is a no-op because the bit widths must
       // be the same. Consequently, we just fold to V.
       return V;
-    
-    if (DestTy->isFloatingPoint()) {
-      assert((DestTy == Type::DoubleTy || DestTy == Type::FloatTy) && 
-             "Unknown FP type!");
-      return ConstantFP::get(APFloat(CI->getValue()));
-    }
+
+    if (DestTy->isFloatingPoint())
+      return ConstantFP::get(APFloat(CI->getValue(),
+                                     DestTy != Type::PPC_FP128Ty));
+
     // Otherwise, can't fold this (vector?)
     return 0;
   }
diff --git a/test/Transforms/InstCombine/2009-02-04-FPBitcast.ll b/test/Transforms/InstCombine/2009-02-04-FPBitcast.ll
new file mode 100644
index 0000000000..4d7b70a115
--- /dev/null
+++ b/test/Transforms/InstCombine/2009-02-04-FPBitcast.ll
@@ -0,0 +1,7 @@
+; RUN: llvm-as < %s | opt -instcombine
+; PR3468
+
+define x86_fp80 @cast() {
+	%tmp = bitcast i80 0 to x86_fp80		; <x86_fp80> [#uses=1]
+	ret x86_fp80 %tmp
+}