1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
|
; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=fma -enable-unsafe-fp-math | FileCheck %s
; If fast-math-flags are propagated correctly, the mul1 expression
; should be recognized as a factor in the last fsub, so we should
; see a mul and add, not a mul and fma:
; a * b - (-a * b) ---> (a * b) + (a * b)
define float @fmf_should_not_break_cse(float %a, float %b) {
; CHECK-LABEL: fmf_should_not_break_cse:
; CHECK: # %bb.0:
; CHECK-NEXT: vmulss %xmm1, %xmm0, %xmm0
; CHECK-NEXT: vaddss %xmm0, %xmm0, %xmm0
; CHECK-NEXT: retq
%mul1 = fmul fast float %a, %b
%nega = fsub fast float 0.0, %a
%mul2 = fmul fast float %nega, %b
%abx2 = fsub fast float %mul1, %mul2
ret float %abx2
}
define <4 x float> @fmf_should_not_break_cse_vector(<4 x float> %a, <4 x float> %b) {
; CHECK-LABEL: fmf_should_not_break_cse_vector:
; CHECK: # %bb.0:
; CHECK-NEXT: vmulps %xmm1, %xmm0, %xmm0
; CHECK-NEXT: vaddps %xmm0, %xmm0, %xmm0
; CHECK-NEXT: retq
%mul1 = fmul fast <4 x float> %a, %b
%nega = fsub fast <4 x float> <float 0.0, float 0.0, float 0.0, float 0.0>, %a
%mul2 = fmul fast <4 x float> %nega, %b
%abx2 = fsub fast <4 x float> %mul1, %mul2
ret <4 x float> %abx2
}
|
