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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
3
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  %mul1 = fmul fast float %a, %b
16  %nega = fsub fast float 0.0, %a
17  %mul2 = fmul fast float %nega, %b
18  %abx2 = fsub fast float %mul1, %mul2
19  ret float %abx2
20}
21
22define <4 x float> @fmf_should_not_break_cse_vector(<4 x float> %a, <4 x float> %b) {
23; CHECK-LABEL: fmf_should_not_break_cse_vector:
24; CHECK:       # %bb.0:
25; CHECK-NEXT:    vmulps %xmm1, %xmm0, %xmm0
26; CHECK-NEXT:    vaddps %xmm0, %xmm0, %xmm0
27; CHECK-NEXT:    retq
28  %mul1 = fmul fast <4 x float> %a, %b
29  %nega = fsub fast <4 x float> <float 0.0, float 0.0, float 0.0, float 0.0>, %a
30  %mul2 = fmul fast <4 x float> %nega, %b
31  %abx2 = fsub fast <4 x float> %mul1, %mul2
32  ret <4 x float> %abx2
33}
34