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| author | Weiming Zhao <weimingz@codeaurora.org> | 2016-08-03 17:05:23 +0000 |
|---|---|---|
| committer | Weiming Zhao <weimingz@codeaurora.org> | 2016-08-03 17:05:23 +0000 |
| commit | 57dc4cf0e1dc149f05569aee7c5dd8fec04f81b4 (patch) | |
| tree | b556506ad1ad97783d201353a01b6c686411b92a /llvm/lib | |
| parent | 8cf51c340dcb0c150a5dcb8c820c758c781404d9 (diff) | |
| download | bcm5719-llvm-57dc4cf0e1dc149f05569aee7c5dd8fec04f81b4.tar.gz bcm5719-llvm-57dc4cf0e1dc149f05569aee7c5dd8fec04f81b4.zip | |
[ARM] Constant Materialize: imms with specific value can be encoded into mov.w
Summary: Thumb2 supports encoding immediates with specific patterns into mov.w by splatting the low 8 bits into other bytes.
Reviewers: john.brawn, jmolloy
Subscribers: jmolloy, aemerson, rengolin, samparker, llvm-commits
Differential Revision: https://reviews.llvm.org/D23090
llvm-svn: 277610
Diffstat (limited to 'llvm/lib')
| -rw-r--r-- | llvm/lib/Target/ARM/ARMISelDAGToDAG.cpp | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/llvm/lib/Target/ARM/ARMISelDAGToDAG.cpp b/llvm/lib/Target/ARM/ARMISelDAGToDAG.cpp index d11de555fa3..01b4e19940d 100644 --- a/llvm/lib/Target/ARM/ARMISelDAGToDAG.cpp +++ b/llvm/lib/Target/ARM/ARMISelDAGToDAG.cpp @@ -476,7 +476,9 @@ bool ARMDAGToDAGISel::isShifterOpProfitable(const SDValue &Shift, unsigned ARMDAGToDAGISel::ConstantMaterializationCost(unsigned Val) const { if (Subtarget->isThumb()) { if (Val <= 255) return 1; // MOV - if (Subtarget->hasV6T2Ops() && Val <= 0xffff) return 1; // MOVW + if (Subtarget->hasV6T2Ops() && + (Val <= 0xffff || ARM_AM::getT2SOImmValSplatVal(Val) != -1)) + return 1; // MOVW if (Val <= 510) return 2; // MOV + ADDi8 if (~Val <= 255) return 2; // MOV + MVN if (ARM_AM::isThumbImmShiftedVal(Val)) return 2; // MOV + LSL |
