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| ; RUN: llc -mtriple=aarch64-none-linux-gnu -aarch64-enable-atomic-cfg-tidy=0 -verify-machineinstrs -o - %s | FileCheck %s
; LLVM should be able to cope with multiple uses of the same flag-setting
; instruction at different points of a routine. Either by rematerializing the
; compare or by saving and restoring the flag register.
declare void @bar()
@var = global i32 0
define i32 @test_multiflag(i32 %n, i32 %m, i32 %o) {
; CHECK-LABEL: test_multiflag:
%test = icmp ne i32 %n, %m
; CHECK: cmp [[LHS:w[0-9]+]], [[RHS:w[0-9]+]]
%val = zext i1 %test to i32
; CHECK: cset {{[xw][0-9]+}}, ne
; CHECK: mov [[RHSCOPY:w[0-9]+]], [[RHS]]
; CHECK: mov [[LHSCOPY:w[0-9]+]], [[LHS]]
store i32 %val, i32* @var
call void @bar()
; CHECK: bl bar
; Currently, the comparison is emitted again. An MSR/MRS pair would also be
; acceptable, but assuming the call preserves NZCV is not.
br i1 %test, label %iftrue, label %iffalse
; CHECK: cmp [[LHSCOPY]], [[RHSCOPY]]
; CHECK: b.eq
iftrue:
ret i32 42
iffalse:
ret i32 0
}
|