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; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
; RUN: llc < %s -mtriple=x86_64-unknown | FileCheck %s -check-prefix=X64
; RUN: llc < %s -mtriple=i686-unknown | FileCheck %s -check-prefix=X86
declare float @llvm.sqrt.f32(float %x);
define float @fast_recip_sqrt(float %x) {
; X64-LABEL: fast_recip_sqrt:
; X64: # %bb.0:
; X64-NEXT: sqrtss %xmm0, %xmm1
; X64-NEXT: movss {{.*#+}} xmm0 = mem[0],zero,zero,zero
; X64-NEXT: divss %xmm1, %xmm0
; X64-NEXT: retq
;
; X86-LABEL: fast_recip_sqrt:
; X86: # %bb.0:
; X86-NEXT: flds {{[0-9]+}}(%esp)
; X86-NEXT: fsqrt
; X86-NEXT: fld1
; X86-NEXT: fdivp %st(1)
; X86-NEXT: retl
%y = call fast float @llvm.sqrt.f32(float %x)
%z = fdiv fast float 1.0, %y
ret float %z
}
declare float @llvm.fmuladd.f32(float %a, float %b, float %c);
define float @fast_fmuladd_opts(float %a , float %b , float %c) {
; X64-LABEL: fast_fmuladd_opts:
; X64: # %bb.0:
; X64-NEXT: movaps %xmm0, %xmm1
; X64-NEXT: addss %xmm1, %xmm1
; X64-NEXT: addss %xmm0, %xmm1
; X64-NEXT: movaps %xmm1, %xmm0
; X64-NEXT: retq
;
; X86-LABEL: fast_fmuladd_opts:
; X86: # %bb.0:
; X86-NEXT: flds {{[0-9]+}}(%esp)
; X86-NEXT: fld %st(0)
; X86-NEXT: fadd %st(1)
; X86-NEXT: faddp %st(1)
; X86-NEXT: retl
%res = call fast float @llvm.fmuladd.f32(float %a, float 2.0, float %a)
ret float %res
}
; The multiply is strict.
@mul1 = common global double 0.000000e+00, align 4
define double @not_so_fast_mul_add(double %x) {
; X64-LABEL: not_so_fast_mul_add:
; X64: # %bb.0:
; X64-NEXT: movsd {{.*#+}} xmm1 = mem[0],zero
; X64-NEXT: mulsd %xmm0, %xmm1
; X64-NEXT: addsd %xmm1, %xmm0
; X64-NEXT: movsd %xmm1, {{.*}}(%rip)
; X64-NEXT: retq
;
; X86-LABEL: not_so_fast_mul_add:
; X86: # %bb.0:
; X86-NEXT: fldl {{[0-9]+}}(%esp)
; X86-NEXT: fld %st(0)
; X86-NEXT: fmull {{\.LCPI.*}}
; X86-NEXT: fadd %st(0), %st(1)
; X86-NEXT: fstpl mul1
; X86-NEXT: retl
%m = fmul double %x, 4.2
%a = fadd fast double %m, %x
store double %m, double* @mul1, align 4
ret double %a
}
; The sqrt is strict.
@sqrt1 = common global float 0.000000e+00, align 4
define float @not_so_fast_recip_sqrt(float %x) {
; X64-LABEL: not_so_fast_recip_sqrt:
; X64: # %bb.0:
; X64-NEXT: sqrtss %xmm0, %xmm1
; X64-NEXT: movss {{.*#+}} xmm0 = mem[0],zero,zero,zero
; X64-NEXT: divss %xmm1, %xmm0
; X64-NEXT: movss %xmm1, {{.*}}(%rip)
; X64-NEXT: retq
;
; X86-LABEL: not_so_fast_recip_sqrt:
; X86: # %bb.0:
; X86-NEXT: flds {{[0-9]+}}(%esp)
; X86-NEXT: fsqrt
; X86-NEXT: fld1
; X86-NEXT: fdiv %st(1)
; X86-NEXT: fxch %st(1)
; X86-NEXT: fstps sqrt1
; X86-NEXT: retl
%y = call float @llvm.sqrt.f32(float %x)
%z = fdiv fast float 1.0, %y
store float %y, float* @sqrt1, align 4
%ret = fadd float %z , 14.5
ret float %z
}
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