diff options
| -rw-r--r-- | lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp | 7 | ||||
| -rw-r--r-- | test/CodeGen/X86/crash.ll | 20 |
2 files changed, 27 insertions, 0 deletions
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp index b9ec4c46f3..f426fb1f3f 100644 --- a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp +++ b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp @@ -1485,7 +1485,14 @@ bool SelectionDAGISel::IsLegalToFold(SDValue N, SDNode *U, SDNode *Root, break; Root = FU; VT = Root->getValueType(Root->getNumValues()-1); + + // If our query node has a flag result with a use, we've walked up it. If + // the user (which has already been selected) has a chain or indirectly uses + // the chain, our WalkChainUsers predicate will not consider it. Because of + // this, we cannot ignore chains in this predicate. + IgnoreChains = false; } + SmallPtrSet<SDNode*, 16> Visited; return !findNonImmUse(Root, N.getNode(), U, Root, Visited, IgnoreChains); diff --git a/test/CodeGen/X86/crash.ll b/test/CodeGen/X86/crash.ll new file mode 100644 index 0000000000..1e13046f2a --- /dev/null +++ b/test/CodeGen/X86/crash.ll @@ -0,0 +1,20 @@ +; RUN: llc -march=x86 %s -o - +; RUN: llc -march=x86-64 %s -o - + +; PR6497 + +; Chain and flag folding issues. +define i32 @test1() nounwind ssp { +entry: + %tmp5.i = volatile load i32* undef ; <i32> [#uses=1] + %conv.i = zext i32 %tmp5.i to i64 ; <i64> [#uses=1] + %tmp12.i = volatile load i32* undef ; <i32> [#uses=1] + %conv13.i = zext i32 %tmp12.i to i64 ; <i64> [#uses=1] + %shl.i = shl i64 %conv13.i, 32 ; <i64> [#uses=1] + %or.i = or i64 %shl.i, %conv.i ; <i64> [#uses=1] + %add16.i = add i64 %or.i, 256 ; <i64> [#uses=1] + %shr.i = lshr i64 %add16.i, 8 ; <i64> [#uses=1] + %conv19.i = trunc i64 %shr.i to i32 ; <i32> [#uses=1] + volatile store i32 %conv19.i, i32* undef + ret i32 undef +} |