From a26276b9498843218ee78c956c478ceebb819ad8 Mon Sep 17 00:00:00 2001 From: Haibo Xu Date: Tue, 20 Aug 2019 09:44:05 +0000 Subject: Enable pkg/bits support on arm64. Signed-off-by: Haibo Xu Change-Id: I490716f0e6204f0b3a43f71931b10d1ca541e128 --- pkg/bits/uint64_arch_arm64_asm.s | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) create mode 100644 pkg/bits/uint64_arch_arm64_asm.s (limited to 'pkg/bits/uint64_arch_arm64_asm.s') diff --git a/pkg/bits/uint64_arch_arm64_asm.s b/pkg/bits/uint64_arch_arm64_asm.s new file mode 100644 index 000000000..814ba562d --- /dev/null +++ b/pkg/bits/uint64_arch_arm64_asm.s @@ -0,0 +1,33 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// +build arm64 + +TEXT ·TrailingZeros64(SB),$0-16 + MOVD x+0(FP), R0 + RBIT R0, R0 + CLZ R0, R0 // return 64 if x == 0 + MOVD R0, ret+8(FP) + RET + +TEXT ·MostSignificantOne64(SB),$0-16 + MOVD x+0(FP), R0 + CLZ R0, R0 // return 64 if x == 0 + MOVD $63, R1 + SUBS R0, R1, R0 // ret = 63 - CLZ + BPL end + MOVD $64, R0 // x == 0 +end: + MOVD R0, ret+8(FP) + RET -- cgit v1.2.3