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; RUN: llc -verify-machineinstrs -o - %s | FileCheck %s
target triple = "arm64--"
; AArch64InstrInfo::optimizeCondBranch() optimizes the
; "x = and y, 256; cmp x, 0; br" from an "and; cbnz" to a tbnz instruction.
; It forgot to clear the a flag resulting in a MachineVerifier complaint.
;
; Writing a stable/simple test is tricky since most tbz instructions are already
; formed in SelectionDAG, optimizeCondBranch() only triggers if the and
; instruction is in a different block than the conditional jump.
;
; CHECK-LABEL: func
; CHECK-NOT: and
; CHECK: tbz
define void @func() {
%c0 = icmp sgt i64 0, 0
br i1 %c0, label %b1, label %b6
b1:
br i1 undef, label %b3, label %b2
b2:
%v0 = tail call i32 @extfunc()
br label %b5
b3:
%v1 = load i32, i32* undef, align 4
%v2 = and i32 %v1, 256
br label %b5
b5:
%v3 = phi i32 [ %v2, %b3 ], [ %v0, %b2 ]
%c1 = icmp eq i32 %v3, 0
br i1 %c1, label %b8, label %b7
b6:
tail call i32 @extfunc()
ret void
b7:
tail call i32 @extfunc()
ret void
b8:
ret void
}
declare i32 @extfunc()
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