RPCS3/llvm
1
0
Fork 0
mirror of https://github.com/RPCS3/llvm.git synced 2025-03-02 15:45:44 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

Fix a DAG combiner assertion failure when constant folding BUILD_VECTORS.

Browse Source 
svn r139159 caused SelectionDAG::getConstant() to promote BUILD_VECTOR operands
with illegal types, even before type legalization.  For this testcase, that led
to one BUILD_VECTOR with i16 operands and another with promoted i32 operands,
which triggered the assertion.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142370 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Bob Wilson 2011-10-18 17:34:47 +00:00
parent 630243a8c2
commit db2b18feba
2 changed files with 23 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
lib/CodeGen/SelectionDAG/DAGCombiner.cpp
View File

@ -7261,8 +7261,19 @@ SDValue DAGCombiner::SimplifyVBinOp(SDNode *N) {
}
EVT VT = LHSOp.getValueType();
assert(RHSOp.getValueType() == VT &&
"SimplifyVBinOp with different BUILD_VECTOR element types");
EVT RVT = RHSOp.getValueType();
if (RVT != VT) {
// Integer BUILD_VECTOR operands may have types larger than the element
// size (e.g., when the element type is not legal). Prior to type
// legalization, the types may not match between the two BUILD_VECTORS.
// Truncate one of the operands to make them match.
if (RVT.getSizeInBits() > VT.getSizeInBits()) {
RHSOp = DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, RHSOp);
} else {
LHSOp = DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), RVT, LHSOp);
VT = RVT;
}
}
SDValue FoldOp = DAG.getNode(N->getOpcode(), LHS.getDebugLoc(), VT,
LHSOp, RHSOp);
if (FoldOp.getOpcode() != ISD::UNDEF &&

10
test/CodeGen/ARM/vector-DAGCombine.ll
View File

@ -123,3 +123,13 @@ define void @orVec(<3 x i8>* %A) nounwind {
ret void
}
; The following test was hitting an assertion in the DAG combiner when
; constant folding the multiply because the "sext undef" was translated to
; a BUILD_VECTOR with i32 0 operands, which did not match the i16 operands
; of the other BUILD_VECTOR.
define i16 @foldBuildVectors() {
%1 = sext <8 x i8> undef to <8 x i16>
%2 = mul <8 x i16> %1, <i16 255, i16 255, i16 255, i16 255, i16 255, i16 255, i16 255, i16 255>
%3 = extractelement <8 x i16> %2, i32 0
ret i16 %3
}