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| ; RUN: llc < %s -mtriple=x86_64-darwin -mcpu=generic | FileCheck %s
; XFAIL: *
; rdar:15661073 simple example of redundant adds
;
; MachineCSE should coalesce trivial subregister copies.
;
; The extra movl+addl should be removed during MachineCSE.
; CHECK-LABEL: redundantadd
; CHECK: cmpq
; CHECK: movq
; CHECK-NOT: movl
; CHECK: addl
; CHECK-NOT: addl
; CHECK: ret
define i64 @redundantadd(i64* %a0, i64* %a1) {
entry:
%tmp8 = load i64, i64* %a0, align 8
%tmp12 = load i64, i64* %a1, align 8
%tmp13 = icmp ult i64 %tmp12, -281474976710656
br i1 %tmp13, label %exit1, label %body
exit1:
unreachable
body:
%tmp14 = trunc i64 %tmp8 to i32
%tmp15 = trunc i64 %tmp12 to i32
%tmp16 = tail call { i32, i1 } @llvm.sadd.with.overflow.i32(i32 %tmp14, i32 %tmp15)
%tmp17 = extractvalue { i32, i1 } %tmp16, 1
br i1 %tmp17, label %exit2, label %return
exit2:
unreachable
return:
%tmp18 = add i64 %tmp12, %tmp8
%tmp19 = and i64 %tmp18, 4294967295
%tmp20 = or i64 %tmp19, -281474976710656
ret i64 %tmp20
}
declare { i32, i1 } @llvm.sadd.with.overflow.i32(i32, i32)
|