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| author | Craig Topper <craig.topper@intel.com> | 2018-09-15 16:23:35 +0000 |
|---|---|---|
| committer | Craig Topper <craig.topper@intel.com> | 2018-09-15 16:23:35 +0000 |
| commit | fe0b973fbfe97d04e796b86455748ff143a5bfef (patch) | |
| tree | 0691d55f43e727aba741daee995ec2ac9a0809af /llvm/lib | |
| parent | 273f755da35656a77e695459d944aab43e12965b (diff) | |
| download | bcm5719-llvm-fe0b973fbfe97d04e796b86455748ff143a5bfef.tar.gz bcm5719-llvm-fe0b973fbfe97d04e796b86455748ff143a5bfef.zip | |
[X86] Remove an fp->int->fp domain crossing in LowerUINT_TO_FP_i64.
Summary: This unfortunately adds a move, but isn't that better than going to the int domain and back?
Reviewers: RKSimon
Reviewed By: RKSimon
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D52134
llvm-svn: 342327
Diffstat (limited to 'llvm/lib')
| -rw-r--r-- | llvm/lib/Target/X86/X86ISelLowering.cpp | 8 |
1 files changed, 3 insertions, 5 deletions
diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp index 26d21d55ba6..14880e40881 100644 --- a/llvm/lib/Target/X86/X86ISelLowering.cpp +++ b/llvm/lib/Target/X86/X86ISelLowering.cpp @@ -16737,13 +16737,11 @@ static SDValue LowerUINT_TO_FP_i64(SDValue Op, SelectionDAG &DAG, SDValue Result; if (Subtarget.hasSSE3()) { - // FIXME: The 'haddpd' instruction may be slower than 'movhlps + addsd'. + // FIXME: The 'haddpd' instruction may be slower than 'shuffle + addsd'. Result = DAG.getNode(X86ISD::FHADD, dl, MVT::v2f64, Sub, Sub); } else { - SDValue S2F = DAG.getBitcast(MVT::v4i32, Sub); - SDValue Shuffle = DAG.getVectorShuffle(MVT::v4i32, dl, S2F, S2F, {2,3,0,1}); - Result = DAG.getNode(ISD::FADD, dl, MVT::v2f64, - DAG.getBitcast(MVT::v2f64, Shuffle), Sub); + SDValue Shuffle = DAG.getVectorShuffle(MVT::v2f64, dl, Sub, Sub, {1,-1}); + Result = DAG.getNode(ISD::FADD, dl, MVT::v2f64, Shuffle, Sub); } return DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, MVT::f64, Result, |
