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| ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
; RUN: llc < %s -mtriple=i386-unknown-unknown -jump-is-expensive=0 | FileCheck %s --check-prefix=JUMP2
; RUN: llc < %s -mtriple=i386-unknown-unknown -jump-is-expensive=1 | FileCheck %s --check-prefix=JUMP1
define void @foo(i32 %X, i32 %Y, i32 %Z) nounwind {
; JUMP2-LABEL: foo:
; JUMP2: # %bb.0: # %entry
; JUMP2-NEXT: cmpl $5, {{[0-9]+}}(%esp)
; JUMP2-NEXT: jl .LBB0_3
; JUMP2-NEXT: # %bb.1: # %entry
; JUMP2-NEXT: cmpl $0, {{[0-9]+}}(%esp)
; JUMP2-NEXT: je .LBB0_3
; JUMP2-NEXT: # %bb.2: # %UnifiedReturnBlock
; JUMP2-NEXT: retl
; JUMP2-NEXT: .LBB0_3: # %cond_true
; JUMP2-NEXT: jmp bar # TAILCALL
;
; JUMP1-LABEL: foo:
; JUMP1: # %bb.0: # %entry
; JUMP1-NEXT: cmpl $0, {{[0-9]+}}(%esp)
; JUMP1-NEXT: setne %al
; JUMP1-NEXT: cmpl $4, {{[0-9]+}}(%esp)
; JUMP1-NEXT: setg %cl
; JUMP1-NEXT: testb %al, %cl
; JUMP1-NEXT: jne .LBB0_1
; JUMP1-NEXT: # %bb.2: # %cond_true
; JUMP1-NEXT: jmp bar # TAILCALL
; JUMP1-NEXT: .LBB0_1: # %UnifiedReturnBlock
; JUMP1-NEXT: retl
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 {
; JUMP2-LABEL: unpredictable:
; JUMP2: # %bb.0: # %entry
; JUMP2-NEXT: cmpl $0, {{[0-9]+}}(%esp)
; JUMP2-NEXT: setne %al
; JUMP2-NEXT: cmpl $4, {{[0-9]+}}(%esp)
; JUMP2-NEXT: setg %cl
; JUMP2-NEXT: testb %al, %cl
; JUMP2-NEXT: jne .LBB1_1
; JUMP2-NEXT: # %bb.2: # %cond_true
; JUMP2-NEXT: jmp bar # TAILCALL
; JUMP2-NEXT: .LBB1_1: # %UnifiedReturnBlock
; JUMP2-NEXT: retl
;
; JUMP1-LABEL: unpredictable:
; JUMP1: # %bb.0: # %entry
; JUMP1-NEXT: cmpl $0, {{[0-9]+}}(%esp)
; JUMP1-NEXT: setne %al
; JUMP1-NEXT: cmpl $4, {{[0-9]+}}(%esp)
; JUMP1-NEXT: setg %cl
; JUMP1-NEXT: testb %al, %cl
; JUMP1-NEXT: jne .LBB1_1
; JUMP1-NEXT: # %bb.2: # %cond_true
; JUMP1-NEXT: jmp bar # TAILCALL
; JUMP1-NEXT: .LBB1_1: # %UnifiedReturnBlock
; JUMP1-NEXT: retl
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 = !{}
|