llvm/test/CodeGen/PowerPC/recipest.ll
Hal Finkel 4a1535c038 Make the PPC fast-math sqrt expansion safe at 0
In fast-math mode sqrt(x) is calculated using the fast expansion of the
reciprocal of the reciprocal sqrt expansion. The reciprocal and reciprocal
sqrt expansions use the associated estimate instructions along with some Newton
iterations. Unfortunately, as a result, sqrt(0) was being calculated as NaN,
which is not correct. Now we explicitly return a result of zero if the input is
zero.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@190624 91177308-0d34-0410-b5e6-96231b3b80d8
2013-09-12 19:04:12 +00:00

230 lines
4.1 KiB
LLVM

; RUN: llc < %s -mtriple=powerpc64-unknown-linux-gnu -mcpu=pwr7 -enable-unsafe-fp-math | FileCheck %s
; RUN: llc < %s -mtriple=powerpc64-unknown-linux-gnu -mcpu=pwr7 | FileCheck -check-prefix=CHECK-SAFE %s
target datalayout = "E-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-f128:128:128-v128:128:128-n32:64"
target triple = "powerpc64-unknown-linux-gnu"
declare double @llvm.sqrt.f64(double)
declare float @llvm.sqrt.f32(float)
declare <4 x float> @llvm.sqrt.v4f32(<4 x float>)
define double @foo(double %a, double %b) nounwind {
entry:
%x = call double @llvm.sqrt.f64(double %b)
%r = fdiv double %a, %x
ret double %r
; CHECK: @foo
; CHECK-DAG: frsqrte
; CHECK-DAG: fnmsub
; CHECK: fmul
; CHECK: fmadd
; CHECK: fmul
; CHECK: fmul
; CHECK: fmadd
; CHECK: fmul
; CHECK: fmul
; CHECK: blr
; CHECK-SAFE: @foo
; CHECK-SAFE: fsqrt
; CHECK-SAFE: fdiv
; CHECK-SAFE: blr
}
define double @foof(double %a, float %b) nounwind {
entry:
%x = call float @llvm.sqrt.f32(float %b)
%y = fpext float %x to double
%r = fdiv double %a, %y
ret double %r
; CHECK: @foof
; CHECK-DAG: frsqrtes
; CHECK-DAG: fnmsubs
; CHECK: fmuls
; CHECK: fmadds
; CHECK: fmuls
; CHECK: fmul
; CHECK: blr
; CHECK-SAFE: @foof
; CHECK-SAFE: fsqrts
; CHECK-SAFE: fdiv
; CHECK-SAFE: blr
}
define float @food(float %a, double %b) nounwind {
entry:
%x = call double @llvm.sqrt.f64(double %b)
%y = fptrunc double %x to float
%r = fdiv float %a, %y
ret float %r
; CHECK: @foo
; CHECK-DAG: frsqrte
; CHECK-DAG: fnmsub
; CHECK: fmul
; CHECK: fmadd
; CHECK: fmul
; CHECK: fmul
; CHECK: fmadd
; CHECK: fmul
; CHECK: frsp
; CHECK: fmuls
; CHECK: blr
; CHECK-SAFE: @foo
; CHECK-SAFE: fsqrt
; CHECK-SAFE: fdivs
; CHECK-SAFE: blr
}
define float @goo(float %a, float %b) nounwind {
entry:
%x = call float @llvm.sqrt.f32(float %b)
%r = fdiv float %a, %x
ret float %r
; CHECK: @goo
; CHECK-DAG: frsqrtes
; CHECK-DAG: fnmsubs
; CHECK: fmuls
; CHECK: fmadds
; CHECK: fmuls
; CHECK: fmuls
; CHECK: blr
; CHECK-SAFE: @goo
; CHECK-SAFE: fsqrts
; CHECK-SAFE: fdivs
; CHECK-SAFE: blr
}
define <4 x float> @hoo(<4 x float> %a, <4 x float> %b) nounwind {
entry:
%x = call <4 x float> @llvm.sqrt.v4f32(<4 x float> %b)
%r = fdiv <4 x float> %a, %x
ret <4 x float> %r
; CHECK: @hoo
; CHECK: vrsqrtefp
; CHECK-SAFE: @hoo
; CHECK-SAFE-NOT: vrsqrtefp
; CHECK-SAFE: blr
}
define double @foo2(double %a, double %b) nounwind {
entry:
%r = fdiv double %a, %b
ret double %r
; CHECK: @foo2
; CHECK-DAG: fre
; CHECK-DAG: fnmsub
; CHECK: fmadd
; CHECK: fnmsub
; CHECK: fmadd
; CHECK: fmul
; CHECK: blr
; CHECK-SAFE: @foo2
; CHECK-SAFE: fdiv
; CHECK-SAFE: blr
}
define float @goo2(float %a, float %b) nounwind {
entry:
%r = fdiv float %a, %b
ret float %r
; CHECK: @goo2
; CHECK-DAG: fres
; CHECK-DAG: fnmsubs
; CHECK: fmadds
; CHECK: fmuls
; CHECK: blr
; CHECK-SAFE: @goo2
; CHECK-SAFE: fdivs
; CHECK-SAFE: blr
}
define <4 x float> @hoo2(<4 x float> %a, <4 x float> %b) nounwind {
entry:
%r = fdiv <4 x float> %a, %b
ret <4 x float> %r
; CHECK: @hoo2
; CHECK: vrefp
; CHECK-SAFE: @hoo2
; CHECK-SAFE-NOT: vrefp
; CHECK-SAFE: blr
}
define double @foo3(double %a) nounwind {
entry:
%r = call double @llvm.sqrt.f64(double %a)
ret double %r
; CHECK: @foo3
; CHECK: fcmpu
; CHECK-DAG: frsqrte
; CHECK-DAG: fnmsub
; CHECK: fmul
; CHECK: fmadd
; CHECK: fmul
; CHECK: fmul
; CHECK: fmadd
; CHECK: fmul
; CHECK: fre
; CHECK: fnmsub
; CHECK: fmadd
; CHECK: fnmsub
; CHECK: fmadd
; CHECK: blr
; CHECK-SAFE: @foo3
; CHECK-SAFE: fsqrt
; CHECK-SAFE: blr
}
define float @goo3(float %a) nounwind {
entry:
%r = call float @llvm.sqrt.f32(float %a)
ret float %r
; CHECK: @goo3
; CHECK: fcmpu
; CHECK-DAG: frsqrtes
; CHECK-DAG: fnmsubs
; CHECK: fmuls
; CHECK: fmadds
; CHECK: fmuls
; CHECK: fres
; CHECK: fnmsubs
; CHECK: fmadds
; CHECK: blr
; CHECK-SAFE: @goo3
; CHECK-SAFE: fsqrts
; CHECK-SAFE: blr
}
define <4 x float> @hoo3(<4 x float> %a) nounwind {
entry:
%r = call <4 x float> @llvm.sqrt.v4f32(<4 x float> %a)
ret <4 x float> %r
; CHECK: @hoo3
; CHECK: vrsqrtefp
; CHECK-DAG: vrefp
; CHECK-DAG: vcmpeqfp
; CHECK-SAFE: @hoo3
; CHECK-SAFE-NOT: vrsqrtefp
; CHECK-SAFE: blr
}