llvm-project/llvm/test/CodeGen/X86/fdiv-combine.ll

32 lines
993 B
LLVM

; RUN: llc < %s -mtriple=x86_64-unknown-unknown | FileCheck %s
; Anything more than one division using a single divisor operand
; should be converted into a reciprocal and multiplication.
define float @div1_arcp(float %x, float %y, float %z) #0 {
; CHECK-LABEL: div1_arcp:
; CHECK: # BB#0:
; CHECK-NEXT: divss %xmm1, %xmm0
; CHECK-NEXT: retq
%div1 = fdiv arcp float %x, %y
ret float %div1
}
define float @div2_arcp(float %x, float %y, float %z) #0 {
; CHECK-LABEL: div2_arcp:
; CHECK: # BB#0:
; CHECK-NEXT: movss {{.*#+}} xmm3 = mem[0],zero,zero,zero
; CHECK-NEXT: divss %xmm2, %xmm3
; CHECK-NEXT: mulss %xmm3, %xmm0
; CHECK-NEXT: mulss %xmm1, %xmm0
; CHECK-NEXT: mulss %xmm3, %xmm0
; CHECK-NEXT: retq
%div1 = fdiv arcp float %x, %z
%mul = fmul arcp float %div1, %y
%div2 = fdiv arcp float %mul, %z
ret float %div2
}
; FIXME: If the backend understands 'arcp', then this attribute is unnecessary.
attributes #0 = { "unsafe-fp-math"="true" }