[llvm] r333262 - [SystemZ] Bugfix in combineSTORE().

[Jonas Paulsson via llvm-commits]

Author: jonpa
Date: Fri May 25 02:01:23 2018
New Revision: 333262

URL: http://llvm.org/viewvc/llvm-project?rev=333262&view=rev
Log:
[SystemZ]  Bugfix in combineSTORE().

Remember to check if store is truncating before calling
combineTruncateExtract().

Review: Ulrich Weigand

Added:
    llvm/trunk/test/CodeGen/SystemZ/dag-combine-04.ll
Modified:
    llvm/trunk/lib/Target/SystemZ/SystemZISelLowering.cpp

Modified: llvm/trunk/lib/Target/SystemZ/SystemZISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/SystemZ/SystemZISelLowering.cpp?rev=333262&r1=333261&r2=333262&view=diff
==============================================================================
--- llvm/trunk/lib/Target/SystemZ/SystemZISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/SystemZ/SystemZISelLowering.cpp Fri May 25 02:01:23 2018
@@ -5357,7 +5357,7 @@ SDValue SystemZTargetLowering::combineST
   // for the extraction to be done on a vMiN value, so that we can use VSTE.
   // If X has wider elements then convert it to:
   // (truncstoreiN (extract_vector_elt (bitcast X), Y2), Z).
-  if (MemVT.isInteger()) {
+  if (MemVT.isInteger() && SN->isTruncatingStore()) {
     if (SDValue Value =
             combineTruncateExtract(SDLoc(N), MemVT, SN->getValue(), DCI)) {
       DCI.AddToWorklist(Value.getNode());

Added: llvm/trunk/test/CodeGen/SystemZ/dag-combine-04.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/SystemZ/dag-combine-04.ll?rev=333262&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/SystemZ/dag-combine-04.ll (added)
+++ llvm/trunk/test/CodeGen/SystemZ/dag-combine-04.ll Fri May 25 02:01:23 2018
@@ -0,0 +1,19 @@
+; Test that SystemZTargetLowering::combineSTORE() does not crash due to not
+; checking if store is actually a truncating store before calling
+; combineTruncateExtract().
+;
+; RUN: llc -mtriple=s390x-linux-gnu -mcpu=z13 < %s
+
+ at g_348 = external dso_local unnamed_addr global [6 x [10 x i16]], align 2
+
+define void @main() local_unnamed_addr {
+bb:
+  %tmp = load i16, i16* getelementptr inbounds ([6 x [10 x i16]], [6 x [10 x i16]]* @g_348, i64 0, i64 1, i64 6), align 2
+  %tmp1 = xor i16 %tmp, 0
+  %tmp2 = insertelement <2 x i16> <i16 undef, i16 0>, i16 %tmp1, i32 0
+  %tmp3 = shufflevector <2 x i16> %tmp2, <2 x i16> undef, <2 x i32> <i32 1, i32 undef>
+  %tmp4 = xor <2 x i16> %tmp2, %tmp3
+  %tmp5 = extractelement <2 x i16> %tmp4, i32 0
+  store i16 %tmp5, i16* getelementptr inbounds ([6 x [10 x i16]], [6 x [10 x i16]]* @g_348, i64 0, i64 1, i64 6), align 2
+  unreachable
+}