llvm/test/Transforms/Reassociate/fast-fp-commute.ll
Owen Anderson 2a949077a9 Add intermediate subtract instructions to reassociation worklist.
We sometimes create intermediate subtract instructions during
reassociation.  Adding these to the worklist to revisit exposes many
additional reassociation opportunities.

Patch by Aditya Nandakumar.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@253240 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-16 18:07:30 +00:00

45 lines
1.1 KiB
LLVM

; RUN: opt -reassociate -S < %s | FileCheck %s
declare void @use(float)
define void @test1(float %x, float %y) {
; CHECK-LABEL: test1
; CHECK: fmul fast float %y, %x
; CHECK: fmul fast float %y, %x
; CHECK: fsub fast float %1, %2
; CHECK: call void @use(float %{{.*}})
; CHECK: call void @use(float %{{.*}})
%1 = fmul fast float %x, %y
%2 = fmul fast float %y, %x
%3 = fsub fast float %1, %2
call void @use(float %1)
call void @use(float %3)
ret void
}
define float @test2(float %x, float %y) {
; CHECK-LABEL: test2
; CHECK-NEXT: fmul fast float %y, %x
; CHECK-NEXT: fmul fast float %y, %x
; CHECK-NEXT: fsub fast float %1, %2
; CHECK-NEXT: ret float %3
%1 = fmul fast float %x, %y
%2 = fmul fast float %y, %x
%3 = fsub fast float %1, %2
ret float %3
}
define float @test3(float %x, float %y) {
; CHECK-LABEL: test3
; CHECK-NEXT: %factor = fmul fast float %x, 2.000000e+00
; CHECK-NEXT: %tmp1 = fmul fast float %factor, %y
; CHECK-NEXT: ret float %tmp1
%1 = fmul fast float %x, %y
%2 = fmul fast float %y, %x
%3 = fadd fast float %1, %2
ret float %3
}