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; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
; RUN: llc -O0 -fast-isel -mtriple=x86_64-- < %s | FileCheck %s
define i32 @test(i64 %arg) nounwind {
; CHECK-LABEL: test:
; CHECK: # %bb.0: # %entry
; CHECK-NEXT: subq $1, %rdi
; CHECK-NEXT: setb %cl
; CHECK-NEXT: xorl %eax, %eax
; CHECK-NEXT: testb $1, %cl
; CHECK-NEXT: movl %eax, {{[-0-9]+}}(%r{{[sb]}}p) # 4-byte Spill
; CHECK-NEXT: jne .LBB0_2
; CHECK-NEXT: # %bb.1: # %no_overflow
; CHECK-NEXT: movl $1, %eax
; CHECK-NEXT: movl %eax, {{[-0-9]+}}(%r{{[sb]}}p) # 4-byte Spill
; CHECK-NEXT: jmp .LBB0_2
; CHECK-NEXT: .LBB0_2: # %merge
; CHECK-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload
; CHECK-NEXT: retq
entry:
%usubo = tail call { i64, i1 } @llvm.usub.with.overflow.i64(i64 %arg, i64 1)
%overflow = extractvalue { i64, i1 } %usubo, 1
br i1 %overflow, label %merge, label %no_overflow
no_overflow:
br label %merge
merge:
%phi = phi i32 [ 1, %no_overflow ], [ 0, %entry ]
ret i32 %phi
}
declare { i64, i1 } @llvm.usub.with.overflow.i64(i64, i64)
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