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| ; RUN: llc -mtriple=aarch64-apple-darwin -fast-isel -fast-isel-abort=1 -verify-machineinstrs < %s | FileCheck %s
; CHECK-LABEL: test_or
; CHECK: cbnz w0, {{LBB[0-9]+_2}}
; CHECK: cbz w1, {{LBB[0-9]+_1}}
define i64 @test_or(i32 %a, i32 %b) {
bb1:
%0 = icmp eq i32 %a, 0
%1 = icmp eq i32 %b, 0
%or.cond = or i1 %0, %1
br i1 %or.cond, label %bb3, label %bb4, !prof !0
bb3:
ret i64 0
bb4:
%2 = call i64 @bar()
ret i64 %2
}
; CHECK-LABEL: test_and
; CHECK: cbnz w0, {{LBB[0-9]+_2}}
; CHECK: cbz w1, {{LBB[0-9]+_1}}
define i64 @test_and(i32 %a, i32 %b) {
bb1:
%0 = icmp ne i32 %a, 0
%1 = icmp ne i32 %b, 0
%or.cond = and i1 %0, %1
br i1 %or.cond, label %bb4, label %bb3, !prof !1
bb3:
ret i64 0
bb4:
%2 = call i64 @bar()
ret i64 %2
}
; If the branch is unpredictable, don't add another branch.
; CHECK-LABEL: test_or_unpredictable
; CHECK: cmp w0, #0
; CHECK-NEXT: cset w8, eq
; CHECK-NEXT: cmp w1, #0
; CHECK-NEXT: cset w9, eq
; CHECK-NEXT: orr w8, w8, w9
; CHECK-NEXT: tbnz w8, #0,
define i64 @test_or_unpredictable(i32 %a, i32 %b) {
bb1:
%0 = icmp eq i32 %a, 0
%1 = icmp eq i32 %b, 0
%or.cond = or i1 %0, %1
br i1 %or.cond, label %bb3, label %bb4, !unpredictable !2
bb3:
ret i64 0
bb4:
%2 = call i64 @bar()
ret i64 %2
}
; CHECK-LABEL: test_and_unpredictable
; CHECK: cmp w0, #0
; CHECK-NEXT: cset w8, ne
; CHECK-NEXT: cmp w1, #0
; CHECK-NEXT: cset w9, ne
; CHECK-NEXT: and w8, w8, w9
; CHECK-NEXT: tbz w8, #0,
define i64 @test_and_unpredictable(i32 %a, i32 %b) {
bb1:
%0 = icmp ne i32 %a, 0
%1 = icmp ne i32 %b, 0
%or.cond = and i1 %0, %1
br i1 %or.cond, label %bb4, label %bb3, !unpredictable !2
bb3:
ret i64 0
bb4:
%2 = call i64 @bar()
ret i64 %2
}
declare i64 @bar()
!0 = !{!"branch_weights", i32 5128, i32 32}
!1 = !{!"branch_weights", i32 1024, i32 4136}
!2 = !{}
|