[llvm-commits] [llvm] r122102 - in /llvm/trunk: lib/CodeGen/SelectionDAG/DAGCombiner.cpp test/CodeGen/ARM/vector-DAGCombine.ll

[Bob Wilson]

Author: bwilson
Date: Fri Dec 17 17:06:49 2010
New Revision: 122102

URL: http://llvm.org/viewvc/llvm-project?rev=122102&view=rev
Log:
Fix a DAGCombiner crash when folding binary vector operations with constant
BUILD_VECTOR operands where the element type is not legal.  I had previously
changed this code to insert TRUNCATE operations, but that was just wrong.

Modified:
    llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
    llvm/trunk/test/CodeGen/ARM/vector-DAGCombine.ll

Modified: llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp?rev=122102&r1=122101&r2=122102&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp Fri Dec 17 17:06:49 2010
@@ -6643,10 +6643,9 @@
   // things. Simplifying them may result in a loss of legality.
   if (LegalOperations) return SDValue();
 
-  EVT VT = N->getValueType(0);
-  assert(VT.isVector() && "SimplifyVBinOp only works on vectors!");
+  assert(N->getValueType(0).isVector() &&
+         "SimplifyVBinOp only works on vectors!");
 
-  EVT EltType = VT.getVectorElementType();
   SDValue LHS = N->getOperand(0);
   SDValue RHS = N->getOperand(1);
   SDValue Shuffle = XformToShuffleWithZero(N);
@@ -6679,14 +6678,10 @@
           break;
       }
 
-      // If the vector element type is not legal, the BUILD_VECTOR operands
-      // are promoted and implicitly truncated.  Make that explicit here.
-      if (LHSOp.getValueType() != EltType)
-        LHSOp = DAG.getNode(ISD::TRUNCATE, LHS.getDebugLoc(), EltType, LHSOp);
-      if (RHSOp.getValueType() != EltType)
-        RHSOp = DAG.getNode(ISD::TRUNCATE, RHS.getDebugLoc(), EltType, RHSOp);
-
-      SDValue FoldOp = DAG.getNode(N->getOpcode(), LHS.getDebugLoc(), EltType,
+      EVT VT = LHSOp.getValueType();
+      assert(RHSOp.getValueType() == VT &&
+             "SimplifyVBinOp with different BUILD_VECTOR element types");
+      SDValue FoldOp = DAG.getNode(N->getOpcode(), LHS.getDebugLoc(), VT,
                                    LHSOp, RHSOp);
       if (FoldOp.getOpcode() != ISD::UNDEF &&
           FoldOp.getOpcode() != ISD::Constant &&
@@ -6696,11 +6691,9 @@
       AddToWorkList(FoldOp.getNode());
     }
 
-    if (Ops.size() == LHS.getNumOperands()) {
-      EVT VT = LHS.getValueType();
-      return DAG.getNode(ISD::BUILD_VECTOR, N->getDebugLoc(), VT,
-                         &Ops[0], Ops.size());
-    }
+    if (Ops.size() == LHS.getNumOperands())
+      return DAG.getNode(ISD::BUILD_VECTOR, N->getDebugLoc(),
+                         LHS.getValueType(), &Ops[0], Ops.size());
   }
 
   return SDValue();

Modified: llvm/trunk/test/CodeGen/ARM/vector-DAGCombine.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/ARM/vector-DAGCombine.ll?rev=122102&r1=122101&r2=122102&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/ARM/vector-DAGCombine.ll (original)
+++ llvm/trunk/test/CodeGen/ARM/vector-DAGCombine.ll Fri Dec 17 17:06:49 2010
@@ -61,3 +61,17 @@
        ret void
 }
 
+; Test folding a binary vector operation with constant BUILD_VECTOR
+; operands with i16 elements.
+define void @test_i16_constant_fold() nounwind optsize {
+entry:
+  %0 = sext <4 x i1> zeroinitializer to <4 x i16>
+  %1 = add <4 x i16> %0, zeroinitializer
+  %2 = shufflevector <4 x i16> %1, <4 x i16> undef, <8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7>
+  %3 = add <8 x i16> %2, <i16 1, i16 1, i16 1, i16 1, i16 1, i16 1, i16 1, i16 1>
+  %4 = trunc <8 x i16> %3 to <8 x i8>
+  tail call void @llvm.arm.neon.vst1.v8i8(i8* undef, <8 x i8> %4, i32 1)
+  unreachable
+}
+
+declare void @llvm.arm.neon.vst1.v8i8(i8*, <8 x i8>, i32) nounwind