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llvm-project/llvm/test/CodeGen/PowerPC/fsub-fneg.ll

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[PowerPC] add fsub-fneg test; NFC This is a test for a transform that was suggested in the post-commit mailing list thread for rL329821. The target in question is not in trunk, so PPC gets to stand in for it because it's the only in-tree target that sets 'isFPExtFree()' to 'true'. llvm-svn: 329963
2018-04-13 06:14:23 +08:00
; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
; RUN: llc -verify-machineinstrs -mtriple=powerpc64le < %s | FileCheck %s
[DAGCombiner, PowerPC] allow X - (fpext(-Y) --> X + fpext(Y) with multiple uses This is a transform that I limited in instcombine in rL329821 because it was creating more instructions in IR when the cast has multiple uses. But if the cast is free, then we can do the transform regardless of other uses because it improves the potential throughput of the calculation by removing a dependency on the fneg. Differential Revision: https://reviews.llvm.org/D45598 llvm-svn: 330098
2018-04-16 00:43:48 +08:00
; When fpext is free, we should look through it for optimizations
[PowerPC] add fsub-fneg test; NFC This is a test for a transform that was suggested in the post-commit mailing list thread for rL329821. The target in question is not in trunk, so PPC gets to stand in for it because it's the only in-tree target that sets 'isFPExtFree()' to 'true'. llvm-svn: 329963
2018-04-13 06:14:23 +08:00
; even if it has multiple uses and produce an 'fadd' here.
; Y - (fpext(-X)) --> Y + fpext(X)
define double @neg_ext_op1_extra_use(float %x, double %y) nounwind {
; CHECK-LABEL: neg_ext_op1_extra_use:
; CHECK: # %bb.0:
[DAGCombiner, PowerPC] allow X - (fpext(-Y) --> X + fpext(Y) with multiple uses This is a transform that I limited in instcombine in rL329821 because it was creating more instructions in IR when the cast has multiple uses. But if the cast is free, then we can do the transform regardless of other uses because it improves the potential throughput of the calculation by removing a dependency on the fneg. Differential Revision: https://reviews.llvm.org/D45598 llvm-svn: 330098
2018-04-16 00:43:48 +08:00
; CHECK-NEXT: xsadddp 0, 2, 1
; CHECK-NEXT: fneg 13, 1
; CHECK-NEXT: xsdivdp 1, 13, 0
[PowerPC] add fsub-fneg test; NFC This is a test for a transform that was suggested in the post-commit mailing list thread for rL329821. The target in question is not in trunk, so PPC gets to stand in for it because it's the only in-tree target that sets 'isFPExtFree()' to 'true'. llvm-svn: 329963
2018-04-13 06:14:23 +08:00
; CHECK-NEXT: blr
%t1 = fsub float -0.0, %x
%t2 = fpext float %t1 to double
%t3 = fsub double %y, %t2
%t4 = fdiv double %t2, %t3
ret double %t4
}