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1; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
2; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=fma -enable-unsafe-fp-math | FileCheck %s
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4; If fast-math-flags are propagated correctly, the mul1 expression
5; should be recognized as a factor in the last fsub, so we should
6; see a mul and add, not a mul and fma:
7; a * b - (-a * b) ---> (a * b) + (a * b)
8
9define float @fmf_should_not_break_cse(float %a, float %b) {
10; CHECK-LABEL: fmf_should_not_break_cse:
11; CHECK:       # %bb.0:
12; CHECK-NEXT:    vmulss %xmm1, %xmm0, %xmm0
13; CHECK-NEXT:    vaddss %xmm0, %xmm0, %xmm0
14; CHECK-NEXT:    retq
15
16  %mul1 = fmul fast float %a, %b
17  %nega = fsub fast float 0.0, %a
18  %mul2 = fmul fast float %nega, %b
19  %abx2 = fsub fast float %mul1, %mul2
20  ret float %abx2
21}
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