65e5824d3a
This is designed to have short startup time, for maximum fuzzing throughput. BUG=skia: GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1589563002 Review URL: https://codereview.chromium.org/1589563002
41 lines
942 B
C++
41 lines
942 B
C++
/*
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* Copyright 2016 Google Inc.
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*
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* Use of this source code is governed by a BSD-style license that can be
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* found in the LICENSE file.
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*/
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#include "Fuzz.h"
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// This really is just an example Fuzz*.cpp file.
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// It tests that two different ways of calculating the Paeth predictor function are equivalent.
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static uint8_t paeth_std(uint8_t a, uint8_t b, uint8_t c) {
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int p = a+b-c;
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int pa = abs(p-a),
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pb = abs(p-b),
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pc = abs(p-c);
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if (pb < pa) { pa = pb; a = b; }
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if (pc < pa) { a = c; }
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return a;
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}
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static uint8_t paeth_alt(uint8_t a, uint8_t b, uint8_t c) {
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int min = SkTMin(a,b),
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max = SkTMax(a,b);
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int delta = (max-min)/3;
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if (c <= min+delta) return max;
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if (c >= max-delta) return min;
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return c;
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}
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DEF_FUZZ(Paeth, fuzz) {
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int a = fuzz->nextU(),
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b = fuzz->nextU(),
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c = fuzz->nextU();
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ASSERT(paeth_alt(a,b,c) == paeth_std(a,b,c));
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}
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