diff options
Diffstat (limited to 'test/CodeGen/X86/fdiv-combine.ll')
| -rw-r--r-- | test/CodeGen/X86/fdiv-combine.ll | 21 |
1 files changed, 19 insertions, 2 deletions
diff --git a/test/CodeGen/X86/fdiv-combine.ll b/test/CodeGen/X86/fdiv-combine.ll index 279bb0624ace..34eac62e3673 100644 --- a/test/CodeGen/X86/fdiv-combine.ll +++ b/test/CodeGen/X86/fdiv-combine.ll @@ -1,4 +1,4 @@ -; RUN: llc < %s -mtriple=x86_64-unknown-unknown | FileCheck %s +; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mcpu=x86-64 | FileCheck %s ; Anything more than one division using a single divisor operand ; should be converted into a reciprocal and multiplication. @@ -17,9 +17,9 @@ define float @div2_arcp(float %x, float %y, float %z) #0 { ; CHECK: # BB#0: ; CHECK-NEXT: movss {{.*#+}} xmm3 = mem[0],zero,zero,zero ; CHECK-NEXT: divss %xmm2, %xmm3 -; CHECK-NEXT: mulss %xmm3, %xmm0 ; CHECK-NEXT: mulss %xmm1, %xmm0 ; CHECK-NEXT: mulss %xmm3, %xmm0 +; CHECK-NEXT: mulss %xmm3, %xmm0 ; CHECK-NEXT: retq %div1 = fdiv arcp float %x, %z %mul = fmul arcp float %div1, %y @@ -27,5 +27,22 @@ define float @div2_arcp(float %x, float %y, float %z) #0 { ret float %div2 } +; If the reciprocal is already calculated, we should not +; generate an extra multiplication by 1.0. + +define double @div3_arcp(double %x, double %y, double %z) #0 { +; CHECK-LABEL: div3_arcp: +; CHECK: # BB#0: +; CHECK-NEXT: movsd{{.*#+}} xmm2 = mem[0],zero +; CHECK-NEXT: divsd %xmm1, %xmm2 +; CHECK-NEXT: mulsd %xmm2, %xmm0 +; CHECK-NEXT: addsd %xmm2, %xmm0 +; CHECK-NEXT: retq + %div1 = fdiv fast double 1.0, %y + %div2 = fdiv fast double %x, %y + %ret = fadd fast double %div2, %div1 + ret double %ret +} + ; FIXME: If the backend understands 'arcp', then this attribute is unnecessary. attributes #0 = { "unsafe-fp-math"="true" } |