llvm-6502/test/CodeGen/Mips/2010-07-20-Select.ll
Evan Cheng 44be1a8d66 Enable machine sinking critical edge splitting. e.g.
define double @foo(double %x, double %y, i1 %c) nounwind {
  %a = fdiv double %x, 3.2
  %z = select i1 %c, double %a, double %y
  ret double %z
}

Was:
_foo:
        divsd   LCPI0_0(%rip), %xmm0
        testb   $1, %dil
        jne     LBB0_2
        movaps  %xmm1, %xmm0
LBB0_2:
        ret

Now:
_foo:
        testb   $1, %dil
        je      LBB0_2
        divsd   LCPI0_0(%rip), %xmm0
        ret
LBB0_2:
        movaps  %xmm1, %xmm0
        ret

This avoids the divsd when early exit is taken.
rdar://8454886


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114372 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-20 22:52:00 +00:00

22 lines
918 B
LLVM

; RUN: llc < %s -march=mips -relocation-model=static | FileCheck %s
; Fix PR7473
define i32 @main() nounwind readnone {
entry:
%a = alloca i32, align 4 ; <i32*> [#uses=2]
%c = alloca i32, align 4 ; <i32*> [#uses=2]
volatile store i32 1, i32* %a, align 4
volatile store i32 0, i32* %c, align 4
%0 = volatile load i32* %a, align 4 ; <i32> [#uses=1]
%1 = icmp eq i32 %0, 0 ; <i1> [#uses=1]
; CHECK: addiu $3, $zero, 0
%iftmp.0.0 = select i1 %1, i32 3, i32 0 ; <i32> [#uses=1]
%2 = volatile load i32* %c, align 4 ; <i32> [#uses=1]
%3 = icmp eq i32 %2, 0 ; <i1> [#uses=1]
; CHECK: addiu $3, $zero, 3
; CHECK: addu $2, $5, $3
%iftmp.2.0 = select i1 %3, i32 0, i32 5 ; <i32> [#uses=1]
%4 = add nsw i32 %iftmp.2.0, %iftmp.0.0 ; <i32> [#uses=1]
ret i32 %4
}