llvm-project/llvm/test/CodeGen/AArch64/subs-to-sub-opt.ll

24 lines
591 B
LLVM

; RUN: llc -mtriple=aarch64-linux-gnu -O3 -o - %s | FileCheck %s
@a = external global i8, align 1
@b = external global i8, align 1
; Test that SUBS is replaced by SUB if condition flags are not used.
define i32 @test01() nounwind {
; CHECK: ldrb {{.*}}
; CHECK-NEXT: ldrb {{.*}}
; CHECK-NEXT: sub {{.*}}
; CHECK-NEXT: cmn {{.*}}
entry:
%0 = load i8, i8* @a, align 1
%conv = zext i8 %0 to i32
%1 = load i8, i8* @b, align 1
%conv1 = zext i8 %1 to i32
%s = sub nsw i32 %conv1, %conv
%cmp0 = icmp eq i32 %s, -1
%cmp1 = sext i1 %cmp0 to i8
store i8 %cmp1, i8* @a
ret i32 0
}