DAGCombiner: Fix crash in select(select) opt.

In case of different types used for the condition of the selects the
select(select) -> select(and) normalisation cannot be performed.

See also: http://reviews.llvm.org/D7622

llvm-svn: 234763

2 files changed, 23 insertions, 2 deletions

diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 37263ff78a8..14449502ee2 100644
--- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -4881,7 +4881,7 @@ SDValue DAGCombiner::visitSELECT(SDNode *N) {
       SDValue N1_0 = N1->getOperand(0);
       SDValue N1_1 = N1->getOperand(1);
       SDValue N1_2 = N1->getOperand(2);
-      if (N1_2 == N2) {
+      if (N1_2 == N2 && N0.getValueType() == N1_0.getValueType()) {
         // Create the actual and node if we can generate good code for it.
         if (!TLI.shouldNormalizeToSelectSequence(*DAG.getContext(), VT)) {
           SDValue And = DAG.getNode(ISD::AND, SDLoc(N), N0.getValueType(),
@@ -4900,7 +4900,7 @@ SDValue DAGCombiner::visitSELECT(SDNode *N) {
       SDValue N2_0 = N2->getOperand(0);
       SDValue N2_1 = N2->getOperand(1);
       SDValue N2_2 = N2->getOperand(2);
-      if (N2_1 == N1) {
+      if (N2_1 == N1 && N0.getValueType() == N2_0.getValueType()) {
         // Create the actual or node if we can generate good code for it.
         if (!TLI.shouldNormalizeToSelectSequence(*DAG.getContext(), VT)) {
           SDValue Or = DAG.getNode(ISD::OR, SDLoc(N), N0.getValueType(),
diff --git a/llvm/test/CodeGen/Mips/dagcombine_crash.ll b/llvm/test/CodeGen/Mips/dagcombine_crash.ll
new file mode 100644
index 00000000000..1fdf09b26dd
--- /dev/null
+++ b/llvm/test/CodeGen/Mips/dagcombine_crash.ll
@@ -0,0 +1,21 @@
+; RUN: llc -o - %s
+; The selection DAG select(select()) normalisation crashed for different types
+; on the condition inputs.
+target datalayout = "E-m:m-p:32:32-i8:8:32-i16:16:32-i64:64-n32-S64"
+target triple = "mips--"
+
+define i64 @foobar(double %a) #0 {
+entry:
+  %0 = bitcast double %a to i64
+  %trunc = trunc i64 %0 to i32
+  %and = and i32 %trunc, 32767
+  %sub = add nsw i32 %and, -16383
+  %cmp = icmp ugt i32 %and, 16382
+  %and5 = and i32 %trunc, 32768
+  %tobool = icmp eq i32 %and5, 0
+  %or = and i1 %cmp, %tobool
+  %cmp6 = icmp ugt i32 %sub, 64
+  %sext = sext i1 %cmp6 to i64
+  %retval.0 = select i1 %or, i64 %sext, i64 0
+  ret i64 %retval.0
+}