; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
; 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.
define void @func() uwtable {
; CHECK-LABEL: func:
; CHECK: // %bb.0:
; CHECK-NEXT: mov w8, #1 // =0x1
; CHECK-NEXT: cbnz w8, .LBB0_3
; CHECK-NEXT: // %bb.1: // %b1
; CHECK-NEXT: cbz wzr, .LBB0_4
; CHECK-NEXT: // %bb.2: // %b3
; CHECK-NEXT: ldr w8, [x8]
; CHECK-NEXT: and w0, w8, #0x100
; CHECK-NEXT: cbz w0, .LBB0_5
; CHECK-NEXT: .LBB0_3: // %common.ret.sink.split
; CHECK-NEXT: b extfunc
; CHECK-NEXT: .LBB0_4: // %b2
; CHECK-NEXT: str x30, [sp, #-16]! // 8-byte Folded Spill
; CHECK-NEXT: .cfi_def_cfa_offset 16
; CHECK-NEXT: .cfi_offset w30, -16
; CHECK-NEXT: bl extfunc
; CHECK-NEXT: ldr x30, [sp], #16 // 8-byte Folded Reload
; CHECK-NEXT: .cfi_def_cfa_offset 0
; CHECK-NEXT: .cfi_restore w30
; CHECK-NEXT: cbnz w0, .LBB0_3
; CHECK-NEXT: .LBB0_5: // %common.ret
; CHECK-NEXT: ret
%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, ptr 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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