1 /*
2  * Copyright 2011 Google Inc.
3  *
4  * Use of this source code is governed by a BSD-style license that can be
5  * found in the LICENSE file.
6  */
7 
8 #include "SkColorData.h"
9 #include "SkEndian.h"
10 #include "SkFDot6.h"
11 #include "SkFixed.h"
12 #include "SkHalf.h"
13 #include "SkMathPriv.h"
14 #include "SkPoint.h"
15 #include "SkRandom.h"
16 #include "Test.h"
17 
test_clz(skiatest::Reporter * reporter)18 static void test_clz(skiatest::Reporter* reporter) {
19     REPORTER_ASSERT(reporter, 32 == SkCLZ(0));
20     REPORTER_ASSERT(reporter, 31 == SkCLZ(1));
21     REPORTER_ASSERT(reporter, 1 == SkCLZ(1 << 30));
22     REPORTER_ASSERT(reporter, 0 == SkCLZ(~0U));
23 
24     SkRandom rand;
25     for (int i = 0; i < 1000; ++i) {
26         uint32_t mask = rand.nextU();
27         // need to get some zeros for testing, but in some obscure way so the
28         // compiler won't "see" that, and work-around calling the functions.
29         mask >>= (mask & 31);
30         int intri = SkCLZ(mask);
31         int porta = SkCLZ_portable(mask);
32         REPORTER_ASSERT(reporter, intri == porta);
33     }
34 }
35 
test_quick_div(skiatest::Reporter * reporter)36 static void test_quick_div(skiatest::Reporter* reporter) {
37     /*
38     The inverse table is generated by turning on SkDebugf in the following test code
39     */
40     SkFixed storage[kInverseTableSize * 2];
41     SkFixed* table = storage + kInverseTableSize;
42 
43     // SkDebugf("static const int gFDot6INVERSE[] = {");
44     for (SkFDot6 i=-kInverseTableSize; i<kInverseTableSize; i++) {
45         if (i != 0) {
46             table[i] = SkFDot6Div(SK_FDot6One, i);
47             REPORTER_ASSERT(reporter, table[i] == gFDot6INVERSE[i + kInverseTableSize]);
48         }
49         // SkDebugf("%d, ", table[i]);
50     }
51     // SkDebugf("}\n");
52 
53 
54     for (SkFDot6 a = -1024; a <= 1024; a++) {
55         for (SkFDot6 b = -1024; b <= 1024; b++) {
56             if (b != 0) {
57                 SkFixed ourAnswer = QuickSkFDot6Div(a, b);
58                 SkFixed directAnswer = SkFDot6Div(a, b);
59                 REPORTER_ASSERT(reporter,
60                     (directAnswer == 0 && ourAnswer == 0) ||
61                     SkFixedDiv(SkAbs32(directAnswer - ourAnswer), SkAbs32(directAnswer)) <= 1 << 10
62                 );
63             }
64         }
65     }
66 }
67 
68 ///////////////////////////////////////////////////////////////////////////////
69 
sk_fsel(float pred,float result_ge,float result_lt)70 static float sk_fsel(float pred, float result_ge, float result_lt) {
71     return pred >= 0 ? result_ge : result_lt;
72 }
73 
fast_floor(float x)74 static float fast_floor(float x) {
75 //    float big = sk_fsel(x, 0x1.0p+23, -0x1.0p+23);
76     float big = sk_fsel(x, (float)(1 << 23), -(float)(1 << 23));
77     return (float)(x + big) - big;
78 }
79 
std_floor(float x)80 static float std_floor(float x) {
81     return sk_float_floor(x);
82 }
83 
test_floor_value(skiatest::Reporter * reporter,float value)84 static void test_floor_value(skiatest::Reporter* reporter, float value) {
85     float fast = fast_floor(value);
86     float std = std_floor(value);
87     if (std != fast) {
88         ERRORF(reporter, "fast_floor(%.9g) == %.9g != %.9g == std_floor(%.9g)",
89                value, fast, std, value);
90     }
91 }
92 
test_floor(skiatest::Reporter * reporter)93 static void test_floor(skiatest::Reporter* reporter) {
94     static const float gVals[] = {
95         0, 1, 1.1f, 1.01f, 1.001f, 1.0001f, 1.00001f, 1.000001f, 1.0000001f
96     };
97 
98     for (size_t i = 0; i < SK_ARRAY_COUNT(gVals); ++i) {
99         test_floor_value(reporter, gVals[i]);
100 //        test_floor_value(reporter, -gVals[i]);
101     }
102 }
103 
104 ///////////////////////////////////////////////////////////////////////////////
105 
106 // test that SkMul16ShiftRound and SkMulDiv255Round return the same result
test_muldivround(skiatest::Reporter * reporter)107 static void test_muldivround(skiatest::Reporter* reporter) {
108 #if 0
109     // this "complete" test is too slow, so we test a random sampling of it
110 
111     for (int a = 0; a <= 32767; ++a) {
112         for (int b = 0; b <= 32767; ++b) {
113             unsigned prod0 = SkMul16ShiftRound(a, b, 8);
114             unsigned prod1 = SkMulDiv255Round(a, b);
115             SkASSERT(prod0 == prod1);
116         }
117     }
118 #endif
119 
120     SkRandom rand;
121     for (int i = 0; i < 10000; ++i) {
122         unsigned a = rand.nextU() & 0x7FFF;
123         unsigned b = rand.nextU() & 0x7FFF;
124 
125         unsigned prod0 = SkMul16ShiftRound(a, b, 8);
126         unsigned prod1 = SkMulDiv255Round(a, b);
127 
128         REPORTER_ASSERT(reporter, prod0 == prod1);
129     }
130 }
131 
float_blend(int src,int dst,float unit)132 static float float_blend(int src, int dst, float unit) {
133     return dst + (src - dst) * unit;
134 }
135 
blend31(int src,int dst,int a31)136 static int blend31(int src, int dst, int a31) {
137     return dst + ((src - dst) * a31 * 2114 >> 16);
138     //    return dst + ((src - dst) * a31 * 33 >> 10);
139 }
140 
blend31_slow(int src,int dst,int a31)141 static int blend31_slow(int src, int dst, int a31) {
142     int prod = src * a31 + (31 - a31) * dst + 16;
143     prod = (prod + (prod >> 5)) >> 5;
144     return prod;
145 }
146 
blend31_round(int src,int dst,int a31)147 static int blend31_round(int src, int dst, int a31) {
148     int prod = (src - dst) * a31 + 16;
149     prod = (prod + (prod >> 5)) >> 5;
150     return dst + prod;
151 }
152 
blend31_old(int src,int dst,int a31)153 static int blend31_old(int src, int dst, int a31) {
154     a31 += a31 >> 4;
155     return dst + ((src - dst) * a31 >> 5);
156 }
157 
158 // suppress unused code warning
159 static int (*blend_functions[])(int, int, int) = {
160     blend31,
161     blend31_slow,
162     blend31_round,
163     blend31_old
164 };
165 
test_blend31()166 static void test_blend31() {
167     int failed = 0;
168     int death = 0;
169     if (false) { // avoid bit rot, suppress warning
170         failed = (*blend_functions[0])(0,0,0);
171     }
172     for (int src = 0; src <= 255; src++) {
173         for (int dst = 0; dst <= 255; dst++) {
174             for (int a = 0; a <= 31; a++) {
175 //                int r0 = blend31(src, dst, a);
176 //                int r0 = blend31_round(src, dst, a);
177 //                int r0 = blend31_old(src, dst, a);
178                 int r0 = blend31_slow(src, dst, a);
179 
180                 float f = float_blend(src, dst, a / 31.f);
181                 int r1 = (int)f;
182                 int r2 = SkScalarRoundToInt(f);
183 
184                 if (r0 != r1 && r0 != r2) {
185                     SkDebugf("src:%d dst:%d a:%d result:%d float:%g\n",
186                                  src,   dst, a,        r0,      f);
187                     failed += 1;
188                 }
189                 if (r0 > 255) {
190                     death += 1;
191                     SkDebugf("death src:%d dst:%d a:%d result:%d float:%g\n",
192                                         src,   dst, a,        r0,      f);
193                 }
194             }
195         }
196     }
197     SkDebugf("---- failed %d death %d\n", failed, death);
198 }
199 
test_blend(skiatest::Reporter * reporter)200 static void test_blend(skiatest::Reporter* reporter) {
201     for (int src = 0; src <= 255; src++) {
202         for (int dst = 0; dst <= 255; dst++) {
203             for (int a = 0; a <= 255; a++) {
204                 int r0 = SkAlphaBlend255(src, dst, a);
205                 float f1 = float_blend(src, dst, a / 255.f);
206                 int r1 = SkScalarRoundToInt(f1);
207 
208                 if (r0 != r1) {
209                     float diff = sk_float_abs(f1 - r1);
210                     diff = sk_float_abs(diff - 0.5f);
211                     if (diff > (1 / 255.f)) {
212                         ERRORF(reporter, "src:%d dst:%d a:%d "
213                                "result:%d float:%g\n", src, dst, a, r0, f1);
214                     }
215                 }
216             }
217         }
218     }
219 }
220 
check_length(skiatest::Reporter * reporter,const SkPoint & p,SkScalar targetLen)221 static void check_length(skiatest::Reporter* reporter,
222                          const SkPoint& p, SkScalar targetLen) {
223     float x = SkScalarToFloat(p.fX);
224     float y = SkScalarToFloat(p.fY);
225     float len = sk_float_sqrt(x*x + y*y);
226 
227     len /= SkScalarToFloat(targetLen);
228 
229     REPORTER_ASSERT(reporter, len > 0.999f && len < 1.001f);
230 }
231 
make_zero()232 static float make_zero() {
233     return sk_float_sin(0);
234 }
235 
unittest_isfinite(skiatest::Reporter * reporter)236 static void unittest_isfinite(skiatest::Reporter* reporter) {
237     float nan = sk_float_asin(2);
238     float inf = 1.0f / make_zero();
239     float big = 3.40282e+038f;
240 
241     REPORTER_ASSERT(reporter, !SkScalarIsNaN(inf));
242     REPORTER_ASSERT(reporter, !SkScalarIsNaN(-inf));
243     REPORTER_ASSERT(reporter, !SkScalarIsFinite(inf));
244     REPORTER_ASSERT(reporter, !SkScalarIsFinite(-inf));
245 
246     REPORTER_ASSERT(reporter,  SkScalarIsNaN(nan));
247     REPORTER_ASSERT(reporter, !SkScalarIsNaN(big));
248     REPORTER_ASSERT(reporter, !SkScalarIsNaN(-big));
249     REPORTER_ASSERT(reporter, !SkScalarIsNaN(0));
250 
251     REPORTER_ASSERT(reporter, !SkScalarIsFinite(nan));
252     REPORTER_ASSERT(reporter,  SkScalarIsFinite(big));
253     REPORTER_ASSERT(reporter,  SkScalarIsFinite(-big));
254     REPORTER_ASSERT(reporter,  SkScalarIsFinite(0));
255 }
256 
unittest_half(skiatest::Reporter * reporter)257 static void unittest_half(skiatest::Reporter* reporter) {
258     static const float gFloats[] = {
259         0.f, 1.f, 0.5f, 0.499999f, 0.5000001f, 1.f/3,
260         -0.f, -1.f, -0.5f, -0.499999f, -0.5000001f, -1.f/3
261     };
262 
263     for (size_t i = 0; i < SK_ARRAY_COUNT(gFloats); ++i) {
264         SkHalf h = SkFloatToHalf(gFloats[i]);
265         float f = SkHalfToFloat(h);
266         REPORTER_ASSERT(reporter, SkScalarNearlyEqual(f, gFloats[i]));
267     }
268 
269     // check some special values
270     union FloatUnion {
271         uint32_t fU;
272         float    fF;
273     };
274 
275     static const FloatUnion largestPositiveHalf = { ((142 << 23) | (1023 << 13)) };
276     SkHalf h = SkFloatToHalf(largestPositiveHalf.fF);
277     float f = SkHalfToFloat(h);
278     REPORTER_ASSERT(reporter, SkScalarNearlyEqual(f, largestPositiveHalf.fF));
279 
280     static const FloatUnion largestNegativeHalf = { (1u << 31) | (142u << 23) | (1023u << 13) };
281     h = SkFloatToHalf(largestNegativeHalf.fF);
282     f = SkHalfToFloat(h);
283     REPORTER_ASSERT(reporter, SkScalarNearlyEqual(f, largestNegativeHalf.fF));
284 
285     static const FloatUnion smallestPositiveHalf = { 102 << 23 };
286     h = SkFloatToHalf(smallestPositiveHalf.fF);
287     f = SkHalfToFloat(h);
288     REPORTER_ASSERT(reporter, SkScalarNearlyEqual(f, smallestPositiveHalf.fF));
289 
290     static const FloatUnion overflowHalf = { ((143 << 23) | (1023 << 13)) };
291     h = SkFloatToHalf(overflowHalf.fF);
292     f = SkHalfToFloat(h);
293     REPORTER_ASSERT(reporter, !SkScalarIsFinite(f) );
294 
295     static const FloatUnion underflowHalf = { 101 << 23 };
296     h = SkFloatToHalf(underflowHalf.fF);
297     f = SkHalfToFloat(h);
298     REPORTER_ASSERT(reporter, f == 0.0f );
299 
300     static const FloatUnion inf32 = { 255 << 23 };
301     h = SkFloatToHalf(inf32.fF);
302     f = SkHalfToFloat(h);
303     REPORTER_ASSERT(reporter, !SkScalarIsFinite(f) );
304 
305     static const FloatUnion nan32 = { 255 << 23 | 1 };
306     h = SkFloatToHalf(nan32.fF);
307     f = SkHalfToFloat(h);
308     REPORTER_ASSERT(reporter, SkScalarIsNaN(f) );
309 
310 }
311 
312 template <typename RSqrtFn>
test_rsqrt(skiatest::Reporter * reporter,RSqrtFn rsqrt)313 static void test_rsqrt(skiatest::Reporter* reporter, RSqrtFn rsqrt) {
314     const float maxRelativeError = 6.50196699e-4f;
315 
316     // test close to 0 up to 1
317     float input = 0.000001f;
318     for (int i = 0; i < 1000; ++i) {
319         float exact = 1.0f/sk_float_sqrt(input);
320         float estimate = rsqrt(input);
321         float relativeError = sk_float_abs(exact - estimate)/exact;
322         REPORTER_ASSERT(reporter, relativeError <= maxRelativeError);
323         input += 0.001f;
324     }
325 
326     // test 1 to ~100
327     input = 1.0f;
328     for (int i = 0; i < 1000; ++i) {
329         float exact = 1.0f/sk_float_sqrt(input);
330         float estimate = rsqrt(input);
331         float relativeError = sk_float_abs(exact - estimate)/exact;
332         REPORTER_ASSERT(reporter, relativeError <= maxRelativeError);
333         input += 0.01f;
334     }
335 
336     // test some big numbers
337     input = 1000000.0f;
338     for (int i = 0; i < 100; ++i) {
339         float exact = 1.0f/sk_float_sqrt(input);
340         float estimate = rsqrt(input);
341         float relativeError = sk_float_abs(exact - estimate)/exact;
342         REPORTER_ASSERT(reporter, relativeError <= maxRelativeError);
343         input += 754326.f;
344     }
345 }
346 
test_muldiv255(skiatest::Reporter * reporter)347 static void test_muldiv255(skiatest::Reporter* reporter) {
348     for (int a = 0; a <= 255; a++) {
349         for (int b = 0; b <= 255; b++) {
350             int ab = a * b;
351             float s = ab / 255.0f;
352             int round = (int)floorf(s + 0.5f);
353             int trunc = (int)floorf(s);
354 
355             int iround = SkMulDiv255Round(a, b);
356             int itrunc = SkMulDiv255Trunc(a, b);
357 
358             REPORTER_ASSERT(reporter, iround == round);
359             REPORTER_ASSERT(reporter, itrunc == trunc);
360 
361             REPORTER_ASSERT(reporter, itrunc <= iround);
362             REPORTER_ASSERT(reporter, iround <= a);
363             REPORTER_ASSERT(reporter, iround <= b);
364         }
365     }
366 }
367 
test_muldiv255ceiling(skiatest::Reporter * reporter)368 static void test_muldiv255ceiling(skiatest::Reporter* reporter) {
369     for (int c = 0; c <= 255; c++) {
370         for (int a = 0; a <= 255; a++) {
371             int product = (c * a + 255);
372             int expected_ceiling = (product + (product >> 8)) >> 8;
373             int webkit_ceiling = (c * a + 254) / 255;
374             REPORTER_ASSERT(reporter, expected_ceiling == webkit_ceiling);
375             int skia_ceiling = SkMulDiv255Ceiling(c, a);
376             REPORTER_ASSERT(reporter, skia_ceiling == webkit_ceiling);
377         }
378     }
379 }
380 
test_copysign(skiatest::Reporter * reporter)381 static void test_copysign(skiatest::Reporter* reporter) {
382     static const int32_t gTriples[] = {
383         // x, y, expected result
384         0, 0, 0,
385         0, 1, 0,
386         0, -1, 0,
387         1, 0, 1,
388         1, 1, 1,
389         1, -1, -1,
390         -1, 0, 1,
391         -1, 1, 1,
392         -1, -1, -1,
393     };
394     for (size_t i = 0; i < SK_ARRAY_COUNT(gTriples); i += 3) {
395         REPORTER_ASSERT(reporter,
396                         SkCopySign32(gTriples[i], gTriples[i+1]) == gTriples[i+2]);
397         float x = (float)gTriples[i];
398         float y = (float)gTriples[i+1];
399         float expected = (float)gTriples[i+2];
400         REPORTER_ASSERT(reporter, sk_float_copysign(x, y) == expected);
401     }
402 
403     SkRandom rand;
404     for (int j = 0; j < 1000; j++) {
405         int ix = rand.nextS();
406         REPORTER_ASSERT(reporter, SkCopySign32(ix, ix) == ix);
407         REPORTER_ASSERT(reporter, SkCopySign32(ix, -ix) == -ix);
408         REPORTER_ASSERT(reporter, SkCopySign32(-ix, ix) == ix);
409         REPORTER_ASSERT(reporter, SkCopySign32(-ix, -ix) == -ix);
410 
411         SkScalar sx = rand.nextSScalar1();
412         REPORTER_ASSERT(reporter, SkScalarCopySign(sx, sx) == sx);
413         REPORTER_ASSERT(reporter, SkScalarCopySign(sx, -sx) == -sx);
414         REPORTER_ASSERT(reporter, SkScalarCopySign(-sx, sx) == sx);
415         REPORTER_ASSERT(reporter, SkScalarCopySign(-sx, -sx) == -sx);
416     }
417 }
418 
DEF_TEST(Math,reporter)419 DEF_TEST(Math, reporter) {
420     int         i;
421     SkRandom    rand;
422 
423     // these should assert
424 #if 0
425     SkToS8(128);
426     SkToS8(-129);
427     SkToU8(256);
428     SkToU8(-5);
429 
430     SkToS16(32768);
431     SkToS16(-32769);
432     SkToU16(65536);
433     SkToU16(-5);
434 
435     if (sizeof(size_t) > 4) {
436         SkToS32(4*1024*1024);
437         SkToS32(-4*1024*1024);
438         SkToU32(5*1024*1024);
439         SkToU32(-5);
440     }
441 #endif
442 
443     test_muldiv255(reporter);
444     test_muldiv255ceiling(reporter);
445     test_copysign(reporter);
446 
447     {
448         SkScalar x = SK_ScalarNaN;
449         REPORTER_ASSERT(reporter, SkScalarIsNaN(x));
450     }
451 
452     for (i = 0; i < 1000; i++) {
453         int value = rand.nextS16();
454         int max = rand.nextU16();
455 
456         int clamp = SkClampMax(value, max);
457         int clamp2 = value < 0 ? 0 : (value > max ? max : value);
458         REPORTER_ASSERT(reporter, clamp == clamp2);
459     }
460 
461     for (i = 0; i < 10000; i++) {
462         SkPoint p;
463 
464         // These random values are being treated as 32-bit-patterns, not as
465         // ints; calling SkIntToScalar() here produces crashes.
466         p.setLength((SkScalar) rand.nextS(),
467                     (SkScalar) rand.nextS(),
468                     SK_Scalar1);
469         check_length(reporter, p, SK_Scalar1);
470         p.setLength((SkScalar) (rand.nextS() >> 13),
471                     (SkScalar) (rand.nextS() >> 13),
472                     SK_Scalar1);
473         check_length(reporter, p, SK_Scalar1);
474     }
475 
476     {
477         SkFixed result = SkFixedDiv(100, 100);
478         REPORTER_ASSERT(reporter, result == SK_Fixed1);
479         result = SkFixedDiv(1, SK_Fixed1);
480         REPORTER_ASSERT(reporter, result == 1);
481         result = SkFixedDiv(10 - 1, SK_Fixed1 * 3);
482         REPORTER_ASSERT(reporter, result == 3);
483     }
484 
485     {
486         REPORTER_ASSERT(reporter, (SkFixedRoundToFixed(-SK_Fixed1 * 10) >> 1) == -SK_Fixed1 * 5);
487         REPORTER_ASSERT(reporter, (SkFixedFloorToFixed(-SK_Fixed1 * 10) >> 1) == -SK_Fixed1 * 5);
488         REPORTER_ASSERT(reporter, (SkFixedCeilToFixed(-SK_Fixed1 * 10) >> 1) == -SK_Fixed1 * 5);
489     }
490 
491     unittest_isfinite(reporter);
492     unittest_half(reporter);
493     test_rsqrt(reporter, sk_float_rsqrt);
494     test_rsqrt(reporter, sk_float_rsqrt_portable);
495 
496     for (i = 0; i < 10000; i++) {
497         SkFixed numer = rand.nextS();
498         SkFixed denom = rand.nextS();
499         SkFixed result = SkFixedDiv(numer, denom);
500         int64_t check = SkLeftShift((int64_t)numer, 16) / denom;
501 
502         (void)SkCLZ(numer);
503         (void)SkCLZ(denom);
504 
505         REPORTER_ASSERT(reporter, result != (SkFixed)SK_NaN32);
506         if (check > SK_MaxS32) {
507             check = SK_MaxS32;
508         } else if (check < -SK_MaxS32) {
509             check = SK_MinS32;
510         }
511         if (result != (int32_t)check) {
512             ERRORF(reporter, "\nFixed Divide: %8x / %8x -> %8x %8x\n", numer, denom, result, check);
513         }
514         REPORTER_ASSERT(reporter, result == (int32_t)check);
515     }
516 
517     test_blend(reporter);
518 
519     if (false) test_floor(reporter);
520 
521     // disable for now
522     if (false) test_blend31();  // avoid bit rot, suppress warning
523 
524     test_muldivround(reporter);
525     test_clz(reporter);
526     test_quick_div(reporter);
527 }
528 
529 template <typename T> struct PairRec {
530     T   fYin;
531     T   fYang;
532 };
533 
DEF_TEST(TestEndian,reporter)534 DEF_TEST(TestEndian, reporter) {
535     static const PairRec<uint16_t> g16[] = {
536         { 0x0,      0x0     },
537         { 0xFFFF,   0xFFFF  },
538         { 0x1122,   0x2211  },
539     };
540     static const PairRec<uint32_t> g32[] = {
541         { 0x0,          0x0         },
542         { 0xFFFFFFFF,   0xFFFFFFFF  },
543         { 0x11223344,   0x44332211  },
544     };
545     static const PairRec<uint64_t> g64[] = {
546         { 0x0,      0x0                             },
547         { 0xFFFFFFFFFFFFFFFFULL,  0xFFFFFFFFFFFFFFFFULL  },
548         { 0x1122334455667788ULL,  0x8877665544332211ULL  },
549     };
550 
551     REPORTER_ASSERT(reporter, 0x1122 == SkTEndianSwap16<0x2211>::value);
552     REPORTER_ASSERT(reporter, 0x11223344 == SkTEndianSwap32<0x44332211>::value);
553     REPORTER_ASSERT(reporter, 0x1122334455667788ULL == SkTEndianSwap64<0x8877665544332211ULL>::value);
554 
555     for (size_t i = 0; i < SK_ARRAY_COUNT(g16); ++i) {
556         REPORTER_ASSERT(reporter, g16[i].fYang == SkEndianSwap16(g16[i].fYin));
557     }
558     for (size_t i = 0; i < SK_ARRAY_COUNT(g32); ++i) {
559         REPORTER_ASSERT(reporter, g32[i].fYang == SkEndianSwap32(g32[i].fYin));
560     }
561     for (size_t i = 0; i < SK_ARRAY_COUNT(g64); ++i) {
562         REPORTER_ASSERT(reporter, g64[i].fYang == SkEndianSwap64(g64[i].fYin));
563     }
564 }
565 
566 template <typename T>
test_divmod(skiatest::Reporter * r)567 static void test_divmod(skiatest::Reporter* r) {
568     const struct {
569         T numer;
570         T denom;
571     } kEdgeCases[] = {
572         {(T)17, (T)17},
573         {(T)17, (T)4},
574         {(T)0,  (T)17},
575         // For unsigned T these negatives are just some large numbers.  Doesn't hurt to test them.
576         {(T)-17, (T)-17},
577         {(T)-17, (T)4},
578         {(T)17,  (T)-4},
579         {(T)-17, (T)-4},
580     };
581 
582     for (size_t i = 0; i < SK_ARRAY_COUNT(kEdgeCases); i++) {
583         const T numer = kEdgeCases[i].numer;
584         const T denom = kEdgeCases[i].denom;
585         T div, mod;
586         SkTDivMod(numer, denom, &div, &mod);
587         REPORTER_ASSERT(r, numer/denom == div);
588         REPORTER_ASSERT(r, numer%denom == mod);
589     }
590 
591     SkRandom rand;
592     for (size_t i = 0; i < 10000; i++) {
593         const T numer = (T)rand.nextS();
594         T denom = 0;
595         while (0 == denom) {
596             denom = (T)rand.nextS();
597         }
598         T div, mod;
599         SkTDivMod(numer, denom, &div, &mod);
600         REPORTER_ASSERT(r, numer/denom == div);
601         REPORTER_ASSERT(r, numer%denom == mod);
602     }
603 }
604 
DEF_TEST(divmod_u8,r)605 DEF_TEST(divmod_u8, r) {
606     test_divmod<uint8_t>(r);
607 }
608 
DEF_TEST(divmod_u16,r)609 DEF_TEST(divmod_u16, r) {
610     test_divmod<uint16_t>(r);
611 }
612 
DEF_TEST(divmod_u32,r)613 DEF_TEST(divmod_u32, r) {
614     test_divmod<uint32_t>(r);
615 }
616 
DEF_TEST(divmod_u64,r)617 DEF_TEST(divmod_u64, r) {
618     test_divmod<uint64_t>(r);
619 }
620 
DEF_TEST(divmod_s8,r)621 DEF_TEST(divmod_s8, r) {
622     test_divmod<int8_t>(r);
623 }
624 
DEF_TEST(divmod_s16,r)625 DEF_TEST(divmod_s16, r) {
626     test_divmod<int16_t>(r);
627 }
628 
DEF_TEST(divmod_s32,r)629 DEF_TEST(divmod_s32, r) {
630     test_divmod<int32_t>(r);
631 }
632 
DEF_TEST(divmod_s64,r)633 DEF_TEST(divmod_s64, r) {
634     test_divmod<int64_t>(r);
635 }
636 
test_nextsizepow2(skiatest::Reporter * r,size_t test,size_t expectedAns)637 static void test_nextsizepow2(skiatest::Reporter* r, size_t test, size_t expectedAns) {
638     size_t ans = GrNextSizePow2(test);
639 
640     REPORTER_ASSERT(r, ans == expectedAns);
641     //SkDebugf("0x%zx -> 0x%zx (0x%zx)\n", test, ans, expectedAns);
642 }
643 
DEF_TEST(GrNextSizePow2,reporter)644 DEF_TEST(GrNextSizePow2, reporter) {
645     constexpr int kNumSizeTBits = 8 * sizeof(size_t);
646 
647     size_t test = 0, expectedAns = 1;
648 
649     test_nextsizepow2(reporter, test, expectedAns);
650 
651     test = 1; expectedAns = 1;
652 
653     for (int i = 1; i < kNumSizeTBits; ++i) {
654         test_nextsizepow2(reporter, test, expectedAns);
655 
656         test++;
657         expectedAns <<= 1;
658 
659         test_nextsizepow2(reporter, test, expectedAns);
660 
661         test = expectedAns;
662     }
663 
664     // For the remaining three tests there is no higher power (of 2)
665     test = 0x1;
666     test <<= kNumSizeTBits-1;
667     test_nextsizepow2(reporter, test, test);
668 
669     test++;
670     test_nextsizepow2(reporter, test, test);
671 
672     test_nextsizepow2(reporter, SIZE_MAX, SIZE_MAX);
673 }
674 
DEF_TEST(FloatSaturate32,reporter)675 DEF_TEST(FloatSaturate32, reporter) {
676     const struct {
677         float   fFloat;
678         int     fExpectedInt;
679     } recs[] = {
680         { 0, 0 },
681         { 100.5f, 100 },
682         { (float)SK_MaxS32, SK_MaxS32FitsInFloat },
683         { (float)SK_MinS32, SK_MinS32FitsInFloat },
684         { SK_MaxS32 * 100.0f, SK_MaxS32FitsInFloat },
685         { SK_MinS32 * 100.0f, SK_MinS32FitsInFloat },
686         { SK_ScalarInfinity, SK_MaxS32FitsInFloat },
687         { SK_ScalarNegativeInfinity, SK_MinS32FitsInFloat },
688         { SK_ScalarNaN, SK_MaxS32FitsInFloat },
689     };
690 
691     for (auto r : recs) {
692         int i = sk_float_saturate2int(r.fFloat);
693         REPORTER_ASSERT(reporter, r.fExpectedInt == i);
694     }
695 }
696 
DEF_TEST(FloatSaturate64,reporter)697 DEF_TEST(FloatSaturate64, reporter) {
698     const struct {
699         float   fFloat;
700         int64_t fExpected64;
701     } recs[] = {
702         { 0, 0 },
703         { 100.5f, 100 },
704         { (float)SK_MaxS64, SK_MaxS64FitsInFloat },
705         { (float)SK_MinS64, SK_MinS64FitsInFloat },
706         { SK_MaxS64 * 100.0f, SK_MaxS64FitsInFloat },
707         { SK_MinS64 * 100.0f, SK_MinS64FitsInFloat },
708         { SK_ScalarInfinity, SK_MaxS64FitsInFloat },
709         { SK_ScalarNegativeInfinity, SK_MinS64FitsInFloat },
710         { SK_ScalarNaN, SK_MaxS64FitsInFloat },
711     };
712 
713     for (auto r : recs) {
714         int64_t i = sk_float_saturate2int64(r.fFloat);
715         REPORTER_ASSERT(reporter, r.fExpected64 == i);
716     }
717 }
718 
DEF_TEST(DoubleSaturate32,reporter)719 DEF_TEST(DoubleSaturate32, reporter) {
720     const struct {
721         double  fDouble;
722         int     fExpectedInt;
723     } recs[] = {
724         { 0, 0 },
725         { 100.5, 100 },
726         { SK_MaxS32, SK_MaxS32 },
727         { SK_MinS32, SK_MinS32 },
728         { SK_MaxS32 - 1, SK_MaxS32 - 1 },
729         { SK_MinS32 + 1, SK_MinS32 + 1 },
730         { SK_MaxS32 * 100.0, SK_MaxS32 },
731         { SK_MinS32 * 100.0, SK_MinS32 },
732         { SK_ScalarInfinity, SK_MaxS32 },
733         { SK_ScalarNegativeInfinity, SK_MinS32 },
734         { SK_ScalarNaN, SK_MaxS32 },
735     };
736 
737     for (auto r : recs) {
738         int i = sk_double_saturate2int(r.fDouble);
739         REPORTER_ASSERT(reporter, r.fExpectedInt == i);
740     }
741 }
742