llvm-6502/test/CodeGen/X86/dagcombine_unsafe_math.ll
Shuxin Yang 98b93e5a94 rdar://13126763
Fix a bug in DAGCombine. The symptom is mistakenly optimizing expression
"x + x*x" into "x * 3.0".


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174239 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-02 00:22:03 +00:00

43 lines
963 B
LLVM

; RUN: llc < %s -enable-unsafe-fp-math -mtriple=x86_64-apple-darwin -mcpu=corei7-avx | FileCheck %s
; rdar://13126763
; Expression "x + x*x" was mistakenly transformed into "x * 3.0f".
define float @test1(float %x) {
%t1 = fmul fast float %x, %x
%t2 = fadd fast float %t1, %x
ret float %t2
; CHECK: test1
; CHECK: vaddss
}
; (x + x) + x => x * 3.0
define float @test2(float %x) {
%t1 = fadd fast float %x, %x
%t2 = fadd fast float %t1, %x
ret float %t2
; CHECK: .long 1077936128
; CHECK: test2
; CHECK: vmulss LCPI1_0(%rip), %xmm0, %xmm0
}
; x + (x + x) => x * 3.0
define float @test3(float %x) {
%t1 = fadd fast float %x, %x
%t2 = fadd fast float %t1, %x
ret float %t2
; CHECK: .long 1077936128
; CHECK: test3
; CHECK: vmulss LCPI2_0(%rip), %xmm0, %xmm0
}
; (y + x) + x != x * 3.0
define float @test4(float %x, float %y) {
%t1 = fadd fast float %x, %y
%t2 = fadd fast float %t1, %x
ret float %t2
; CHECK: test4
; CHECK: vaddss
}