Fix a bug in my patch last night that broke InstCombine/2007-10-12-Crash.ll

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@42920 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp
index 2c88279afb092c3fb0fa629bd27a458bdf5707ea..3096cab4c3ce35ca4d5989c9925fd08f18384c29 100644 (file)
--- a/lib/Transforms/Scalar/InstructionCombining.cpp
+++ b/lib/Transforms/Scalar/InstructionCombining.cpp
@@ -8643,8 +8643,14 @@ Instruction *InstCombiner::visitGetElementPtrInst(GetElementPtrInst &GEP) {
       // converted to match the type of the cast, don't touch this.
       if (isa<AllocationInst>(BCI->getOperand(0))) {
         // See if the bitcast simplifies, if so, don't nuke this GEP yet.
-        if (visitBitCast(*BCI))
+        if (Instruction *I = visitBitCast(*BCI)) {
+          if (I != BCI) {
+            I->takeName(BCI);
+            BCI->getParent()->getInstList().insert(BCI, I);
+            ReplaceInstUsesWith(*BCI, I);
+          }
           return &GEP;
+        }
       }
       return new BitCastInst(BCI->getOperand(0), GEP.getType());
     }

diff --git a/test/Transforms/InstCombine/2007-10-12-Crash.ll b/test/Transforms/InstCombine/2007-10-12-Crash.ll
new file mode 100644 (file)
index 0000000..ed98fcd
--- /dev/null
+++ b/test/Transforms/InstCombine/2007-10-12-Crash.ll
@@ -0,0 +1,38 @@
+; RUN: llvm-as < %s | opt -instcombine -disable-output
+
+       %struct.Ray = type { %struct.Vec, %struct.Vec }
+       %struct.Scene = type { i32 (...)** }
+       %struct.Vec = type { double, double, double }
+
+declare double @_Z9ray_traceRK3VecRK3RayRK5Scene(%struct.Vec*, %struct.Ray*, %struct.Scene*)
+
+define i32 @main(i32 %argc, i8** %argv) {
+entry:
+       %tmp3 = alloca %struct.Ray, align 4             ; <%struct.Ray*> [#uses=2]
+       %tmp97 = icmp slt i32 0, 512            ; <i1> [#uses=1]
+       br i1 %tmp97, label %bb71, label %bb108
+
+bb29:          ; preds = %bb62
+       %tmp322 = bitcast %struct.Ray* %tmp3 to %struct.Vec*            ; <%struct.Vec*> [#uses=1]
+       %tmp322.0 = getelementptr %struct.Vec* %tmp322, i32 0, i32 0            ; <double*> [#uses=1]
+       store double 0.000000e+00, double* %tmp322.0
+       %tmp57 = call double @_Z9ray_traceRK3VecRK3RayRK5Scene( %struct.Vec* null, %struct.Ray* %tmp3, %struct.Scene* null )            ; <double> [#uses=0]
+       br label %bb62
+
+bb62:          ; preds = %bb71, %bb29
+       %tmp65 = icmp slt i32 0, 4              ; <i1> [#uses=1]
+       br i1 %tmp65, label %bb29, label %bb68
+
+bb68:          ; preds = %bb62
+       ret i32 0
+
+bb71:          ; preds = %entry
+       %tmp74 = icmp slt i32 0, 4              ; <i1> [#uses=1]
+       br i1 %tmp74, label %bb62, label %bb77
+
+bb77:          ; preds = %bb71
+       ret i32 0
+
+bb108:         ; preds = %entry
+       ret i32 0
+}