You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
49 lines
1.0 KiB
49 lines
1.0 KiB
4 months ago
|
; 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: tbnz
|
||
|
|
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()
|