Fix PR5471 by removing an instcombine xform. Some pieces of the code

generates store to undef and some generates store to null as the idiom
for undefined behavior.  Since simplifycfg zaps both, don't remove the
undefined behavior in instcombine.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89971 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp
index 670dd1162bd2c3e0c134243ee424eb2268e5fdf4..f997d60a85ee56d17408cc9b3fc2359872b69b31 100644 (file)
--- a/lib/Transforms/Scalar/InstructionCombining.cpp
+++ b/lib/Transforms/Scalar/InstructionCombining.cpp
@@ -12096,12 +12096,6 @@ Instruction *InstCombiner::visitStoreInst(StoreInst &SI) {
   Value *Val = SI.getOperand(0);
   Value *Ptr = SI.getOperand(1);
 
-  if (isa<UndefValue>(Ptr)) {     // store X, undef -> noop (even if volatile)
-    EraseInstFromFunction(SI);
-    ++NumCombined;
-    return 0;
-  }
-  
   // If the RHS is an alloca with a single use, zapify the store, making the
   // alloca dead.
   // If the RHS is an alloca with a two uses, the other one being a 

diff --git a/test/Transforms/InstCombine/crash.ll b/test/Transforms/InstCombine/crash.ll
index fbac472e19727865cae7016372b5dee31abdc172..1528f6ddf3c026275219eb23ae5dbf5966d90c7c 100644 (file)
--- a/test/Transforms/InstCombine/crash.ll
+++ b/test/Transforms/InstCombine/crash.ll
@@ -125,3 +125,15 @@ l10:
   %v11 = select i1 %v5_, i64 0, i64 %v6
   ret i64 %v11
 }
+
+; PR5471
+define arm_apcscc i32 @test5a() {
+       ret i32 0
+}
+
+define arm_apcscc void @test5() {
+       store i1 true, i1* undef
+       %1 = invoke i32 @test5a() to label %exit unwind label %exit
+exit:
+       ret void
+}

diff --git a/test/Transforms/InstCombine/store.ll b/test/Transforms/InstCombine/store.ll
index 314441eb86530bb862e6e8509e89ff31d3ac456d..64460d7a6d610e5c0ea5e2070890cea2f4c9a178 100644 (file)
--- a/test/Transforms/InstCombine/store.ll
+++ b/test/Transforms/InstCombine/store.ll
@@ -6,6 +6,7 @@ define void @test1(i32* %P) {
         store i32 124, i32* null
         ret void
 ; CHECK: @test1(
+; CHECK-NEXT: store i32 123, i32* undef
 ; CHECK-NEXT: store i32 undef, i32* null
 ; CHECK-NEXT: ret void
 }