File: or-branch.ll

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llvm-toolchain-3.8 1%3A3.8.1-24
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; RUN: llc < %s -mtriple=i386-unknown-unknown -jump-is-expensive=0 | FileCheck %s --check-prefix=JUMP2 --check-prefix=CHECK
; RUN: llc < %s -mtriple=i386-unknown-unknown -jump-is-expensive=1 | FileCheck %s --check-prefix=JUMP1 --check-prefix=CHECK

define void @foo(i32 %X, i32 %Y, i32 %Z) nounwind {
; JUMP2-LABEL: foo:
; JUMP2-DAG:     jl
; JUMP2-DAG:     je
;
; JUMP1-LABEL: foo:
; JUMP1-DAG:     sete
; JUMP1-DAG:     setl
; JUMP1:         orb
; JUMP1:         jne
entry:
  %tmp1 = icmp eq i32 %X, 0
  %tmp3 = icmp slt i32 %Y, 5
  %tmp4 = or i1 %tmp3, %tmp1
  br i1 %tmp4, label %cond_true, label %UnifiedReturnBlock

cond_true:
  %tmp5 = tail call i32 (...) @bar( )
  ret void

UnifiedReturnBlock:
  ret void
}

; If the branch is unpredictable, don't add another branch
; regardless of whether they are expensive or not.

define void @unpredictable(i32 %X, i32 %Y, i32 %Z) nounwind {
; CHECK-LABEL: unpredictable:
; CHECK-DAG:     sete
; CHECK-DAG:     setl
; CHECK:         orb
; CHECK:         jne
entry:
  %tmp1 = icmp eq i32 %X, 0
  %tmp3 = icmp slt i32 %Y, 5
  %tmp4 = or i1 %tmp3, %tmp1
  br i1 %tmp4, label %cond_true, label %UnifiedReturnBlock, !unpredictable !0

cond_true:
  %tmp5 = tail call i32 (...) @bar( )
  ret void

UnifiedReturnBlock:
  ret void
}

declare i32 @bar(...)

!0 = !{}