gvisor/pkg/sentry/time/muldiv_arm64.s

45 lines
1.2 KiB
ArmAsm

// Copyright 2018 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.
#include "textflag.h"
// Documentation is available in parameters.go.
//
// func muldiv64(value, multiplier, divisor uint64) (uint64, bool)
TEXT ·muldiv64(SB),NOSPLIT,$40-33
MOVD value+0(FP), R0
MOVD multiplier+8(FP), R1
MOVD divisor+16(FP), R2
UMULH R0, R1, R3
MUL R0, R1, R4
CMP R2, R3
BHS overflow
MOVD R3, 8(RSP)
MOVD R4, 16(RSP)
MOVD R2, 24(RSP)
CALL ·divWW(SB)
MOVD 32(RSP), R0
MOVD R0, result+24(FP)
MOVD $1, R0
MOVB R0, ok+32(FP)
RET
overflow:
MOVD ZR, result+24(FP)
MOVB ZR, ok+32(FP)
RET