diff options
| author | Evan Cheng <evan.cheng@apple.com> | 2005-12-14 02:19:23 +0000 |
|---|---|---|
| committer | Evan Cheng <evan.cheng@apple.com> | 2005-12-14 02:19:23 +0000 |
| commit | 110dec20008c94216a486f5c0d2eba30cbc2deef (patch) | |
| tree | a3a238525f3019a64c5a84def552b3f872ef94e9 /lib/CodeGen/SelectionDAG/DAGCombiner.cpp | |
| parent | 3fb6877cb4d49883726850e0bc6ca6550000abdf (diff) | |
Fold (zext (load x) to (zextload x).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@24702 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/CodeGen/SelectionDAG/DAGCombiner.cpp')
| -rw-r--r-- | lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 19 |
1 files changed, 18 insertions, 1 deletions
diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp index 7adfecb222..acd80cf0dc 100644 --- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -1552,7 +1552,7 @@ SDOperand DAGCombiner::visitSIGN_EXTEND(SDNode *N) { TLI.isOperationLegal(ISD::SIGN_EXTEND_INREG, N0.getValueType()))) return DAG.getNode(ISD::SIGN_EXTEND_INREG, VT, N0.getOperand(0), DAG.getValueType(N0.getValueType())); - // fold (sext (load x)) -> (sextload x) + // fold (sext (load x)) -> (sext (truncate (sextload x))) if (N0.getOpcode() == ISD::LOAD && N0.hasOneUse()) { SDOperand ExtLoad = DAG.getExtLoad(ISD::SEXTLOAD, VT, N0.getOperand(0), N0.getOperand(1), N0.getOperand(2), @@ -1576,6 +1576,23 @@ SDOperand DAGCombiner::visitZERO_EXTEND(SDNode *N) { // fold (zext (zext x)) -> (zext x) if (N0.getOpcode() == ISD::ZERO_EXTEND) return DAG.getNode(ISD::ZERO_EXTEND, VT, N0.getOperand(0)); + // fold (zext (zextload x)) -> (zextload x) + if (N0.getOpcode() == ISD::ZEXTLOAD && VT == N0.getValueType()) + return N0; + // fold (zext (truncate x)) -> (zextinreg x) iff x size == zext size. + if (N0.getOpcode() == ISD::TRUNCATE && N0.getOperand(0).getValueType() == VT&& + !AfterLegalize) + return DAG.getZeroExtendInReg(N0.getOperand(0), VT); + // fold (zext (load x)) -> (zext (truncate (zextload x))) + if (N0.getOpcode() == ISD::LOAD && N0.hasOneUse()) { + SDOperand ExtLoad = DAG.getExtLoad(ISD::ZEXTLOAD, VT, N0.getOperand(0), + N0.getOperand(1), N0.getOperand(2), + N0.getValueType()); + WorkList.push_back(N); + CombineTo(N0.Val, DAG.getNode(ISD::TRUNCATE, N0.getValueType(), ExtLoad), + ExtLoad.getValue(1)); + return SDOperand(); + } return SDOperand(); } |