From: Mehdi Amini <mehdi.amini@apple.com>
Date: Fri, 16 Jan 2015 03:00:58 +0000 (+0000)
Subject: Fix Reassociate handling of constant in presence of undef float
X-Git-Url: http://plrg.eecs.uci.edu/git/?p=oota-llvm.git;a=commitdiff_plain;h=525f296ef1f3f9f0254dab3dc30aef1dce4a7796

Fix Reassociate handling of constant in presence of undef float

http://reviews.llvm.org/D6993

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226245 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Transforms/Scalar/Reassociate.cpp b/lib/Transforms/Scalar/Reassociate.cpp
index 4e022556f9c..0fd64e31dfe 100644
--- a/lib/Transforms/Scalar/Reassociate.cpp
+++ b/lib/Transforms/Scalar/Reassociate.cpp
@@ -917,10 +917,13 @@ void Reassociate::RewriteExprTree(BinaryOperator *I,
 /// version of the value is returned, and BI is left pointing at the instruction
 /// that should be processed next by the reassociation pass.
 static Value *NegateValue(Value *V, Instruction *BI) {
-  if (ConstantFP *C = dyn_cast<ConstantFP>(V))
-    return ConstantExpr::getFNeg(C);
-  if (Constant *C = dyn_cast<Constant>(V))
+  if (Constant *C = dyn_cast<Constant>(V)) {
+    if (C->getType()->isFPOrFPVectorTy()) {
+      return ConstantExpr::getFNeg(C);
+    }
     return ConstantExpr::getNeg(C);
+  }
+
 
   // We are trying to expose opportunity for reassociation.  One of the things
   // that we want to do to achieve this is to push a negation as deep into an
diff --git a/test/Transforms/Reassociate/crash2.ll b/test/Transforms/Reassociate/crash2.ll
new file mode 100644
index 00000000000..b51a88ca674
--- /dev/null
+++ b/test/Transforms/Reassociate/crash2.ll
@@ -0,0 +1,25 @@
+; RUN: opt -reassociate %s -S -o - | FileCheck %s
+
+; Reassociate pass used to crash on these example
+
+
+define float @undef1() {
+wrapper_entry:
+; CHECK-LABEL: @undef1
+; CHECK: ret float fadd (float undef, float fadd (float undef, float fadd (float fsub (float -0.000000e+00, float undef), float fsub (float -0.000000e+00, float undef))))
+  %0 = fadd fast float undef, undef
+  %1 = fsub fast float undef, %0
+  %2 = fadd fast float undef, %1
+  ret float %2
+}
+
+define void @undef2() {
+wrapper_entry:
+; CHECK-LABEL: @undef2
+; CHECK: unreachable
+  %0 = fadd fast float undef, undef
+  %1 = fadd fast float %0, 1.000000e+00
+  %2 = fsub fast float %0, %1
+  %3 = fmul fast float %2, 2.000000e+00
+  unreachable
+}