Consider expression "0.0 - X" as the negation of X if

- this expression is explicitly marked no-signed-zero, or
  - no-signed-zero of this expression can be derived from some context.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171922 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Shuxin Yang
2013-01-09 00:13:41 +00:00
parent b6714227ed
commit 935e35d2b9
7 changed files with 35 additions and 9 deletions

View File

@@ -243,5 +243,16 @@ define float @fmul5(float %f1, float %f2) {
; CHECK: fdiv fast float %f1, 0x47E8000000000000
}
; =========================================================================
;
; Testing-cases about negation
;
; =========================================================================
define float @fneg1(float %f1, float %f2) {
%sub = fsub float -0.000000e+00, %f1
%sub1 = fsub nsz float 0.000000e+00, %f2
%mul = fmul float %sub, %sub1
ret float %mul
; CHECK: @fneg1
; CHECK: fmul float %f1, %f2
}