use-add-flags.ll
2.53 KB
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; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
; RUN: llc < %s -mtriple=x86_64-linux | FileCheck %s --check-prefix=LNX
; RUN: llc < %s -mtriple=x86_64-win32 | FileCheck %s --check-prefix=WIN
; Reuse the flags value from the add instructions instead of emitting separate
; testl instructions.
; Use the flags on the add.
define i32 @test1(i32* %x, i32 %y, i32 %a, i32 %b) nounwind {
; LNX-LABEL: test1:
; LNX: # %bb.0:
; LNX-NEXT: movl %edx, %eax
; LNX-NEXT: addl (%rdi), %esi
; LNX-NEXT: cmovnsl %ecx, %eax
; LNX-NEXT: retq
;
; WIN-LABEL: test1:
; WIN: # %bb.0:
; WIN-NEXT: movl %r8d, %eax
; WIN-NEXT: addl (%rcx), %edx
; WIN-NEXT: cmovnsl %r9d, %eax
; WIN-NEXT: retq
%tmp2 = load i32, i32* %x, align 4 ; <i32> [#uses=1]
%tmp4 = add i32 %tmp2, %y ; <i32> [#uses=1]
%tmp5 = icmp slt i32 %tmp4, 0 ; <i1> [#uses=1]
%tmp.0 = select i1 %tmp5, i32 %a, i32 %b ; <i32> [#uses=1]
ret i32 %tmp.0
}
declare void @foo(i32)
; Don't use the flags result of the and here, since the and has no
; other use. A simple test is better.
define void @test2(i32 %x) nounwind {
; LNX-LABEL: test2:
; LNX: # %bb.0:
; LNX-NEXT: testb $16, %dil
; LNX-NEXT: jne .LBB1_2
; LNX-NEXT: # %bb.1: # %true
; LNX-NEXT: pushq %rax
; LNX-NEXT: callq foo
; LNX-NEXT: popq %rax
; LNX-NEXT: .LBB1_2: # %false
; LNX-NEXT: retq
;
; WIN-LABEL: test2:
; WIN: # %bb.0:
; WIN-NEXT: subq $40, %rsp
; WIN-NEXT: testb $16, %cl
; WIN-NEXT: jne .LBB1_2
; WIN-NEXT: # %bb.1: # %true
; WIN-NEXT: callq foo
; WIN-NEXT: .LBB1_2: # %false
; WIN-NEXT: addq $40, %rsp
; WIN-NEXT: retq
%y = and i32 %x, 16
%t = icmp eq i32 %y, 0
br i1 %t, label %true, label %false
true:
call void @foo(i32 %x)
ret void
false:
ret void
}
; Do use the flags result of the and here, since the and has another use.
define void @test3(i32 %x) nounwind {
; LNX-LABEL: test3:
; LNX: # %bb.0:
; LNX-NEXT: andl $16, %edi
; LNX-NEXT: jne .LBB2_2
; LNX-NEXT: # %bb.1: # %true
; LNX-NEXT: pushq %rax
; LNX-NEXT: callq foo
; LNX-NEXT: popq %rax
; LNX-NEXT: .LBB2_2: # %false
; LNX-NEXT: retq
;
; WIN-LABEL: test3:
; WIN: # %bb.0:
; WIN-NEXT: subq $40, %rsp
; WIN-NEXT: andl $16, %ecx
; WIN-NEXT: jne .LBB2_2
; WIN-NEXT: # %bb.1: # %true
; WIN-NEXT: callq foo
; WIN-NEXT: .LBB2_2: # %false
; WIN-NEXT: addq $40, %rsp
; WIN-NEXT: retq
%y = and i32 %x, 16
%t = icmp eq i32 %y, 0
br i1 %t, label %true, label %false
true:
call void @foo(i32 %y)
ret void
false:
ret void
}