2021-10-25 01:49:04 +00:00
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/*
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Copyright 2021 Erigon contributors
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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*/
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2023-09-20 12:50:25 +00:00
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package math
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2021-10-22 02:12:39 +00:00
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import (
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2023-09-20 12:50:25 +00:00
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"math/bits"
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2021-10-22 02:12:39 +00:00
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)
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2023-09-20 12:50:25 +00:00
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// SafeMul returns x*y and checks for overflow.
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func SafeMul(x, y uint64) (uint64, bool) {
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hi, lo := bits.Mul64(x, y)
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return lo, hi != 0
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2021-10-22 02:12:39 +00:00
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}
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2023-09-20 12:50:25 +00:00
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// SafeAdd returns x+y and checks for overflow.
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func SafeAdd(x, y uint64) (uint64, bool) {
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sum, carryOut := bits.Add64(x, y, 0)
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return sum, carryOut != 0
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2023-05-08 05:22:24 +00:00
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}
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