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| author | Evan Cheng <evan.cheng@apple.com> | 2011-03-14 18:15:55 +0000 |
|---|---|---|
| committer | Evan Cheng <evan.cheng@apple.com> | 2011-03-14 18:15:55 +0000 |
| commit | 5ae1da96f2ac4a68543295f227398f8e93018eb0 (patch) | |
| tree | c200ba1c32aed32bd221ca5cd0c91d05a5772bfa /lib/CodeGen/SelectionDAG/SelectionDAG.cpp | |
| parent | 21a6179c9daaaa38be40b53d6993404856e20dc1 (diff) | |
Minor optimization. sign-ext/anyext of undef is still undef.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127598 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/CodeGen/SelectionDAG/SelectionDAG.cpp')
| -rw-r--r-- | lib/CodeGen/SelectionDAG/SelectionDAG.cpp | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp index 8deaae935a..2c97d35618 100644 --- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp +++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp @@ -2482,6 +2482,8 @@ SDValue SelectionDAG::getNode(unsigned Opcode, DebugLoc DL, "Vector element count mismatch!"); if (OpOpcode == ISD::SIGN_EXTEND || OpOpcode == ISD::ZERO_EXTEND) return getNode(OpOpcode, DL, VT, Operand.getNode()->getOperand(0)); + else if (OpOpcode == ISD::UNDEF) + return getUNDEF(VT); break; case ISD::ZERO_EXTEND: assert(VT.isInteger() && Operand.getValueType().isInteger() && @@ -2512,6 +2514,8 @@ SDValue SelectionDAG::getNode(unsigned Opcode, DebugLoc DL, OpOpcode == ISD::ANY_EXTEND) // (ext (zext x)) -> (zext x) and (ext (sext x)) -> (sext x) return getNode(OpOpcode, DL, VT, Operand.getNode()->getOperand(0)); + else if (OpOpcode == ISD::UNDEF) + return getUNDEF(VT); // (ext (trunx x)) -> x if (OpOpcode == ISD::TRUNCATE) { |