fix fuzzers

Many old pathops-related fuzz failures have built up while
the codebase was under a state a flux. Now that the code
is stable, address these failures.

Most of the CL plumbs the debug global state to downstream
routines so that, if the data is not trusted (ala fuzzed)
the function can safely exit without asserting.

TBR=reed@google.com
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2426173002

Review-Url: https://chromiumcodereview.appspot.com/2426173002
diff --git a/tests/PathOpsCubicIntersectionTest.cpp b/tests/PathOpsCubicIntersectionTest.cpp
index 07852bc..e69aff8 100644
--- a/tests/PathOpsCubicIntersectionTest.cpp
+++ b/tests/PathOpsCubicIntersectionTest.cpp
@@ -19,11 +19,14 @@
 static void standardTestCases(skiatest::Reporter* reporter) {
     for (size_t index = firstCubicIntersectionTest; index < tests_count; ++index) {
         int iIndex = static_cast<int>(index);
-        const SkDCubic& cubic1 = tests[index][0];
-        const SkDCubic& cubic2 = tests[index][1];
+        const CubicPts& cubic1 = tests[index][0];
+        const CubicPts& cubic2 = tests[index][1];
+        SkDCubic c1, c2;
+        c1.debugSet(cubic1.fPts);
+        c2.debugSet(cubic2.fPts);
         SkReduceOrder reduce1, reduce2;
-        int order1 = reduce1.reduce(cubic1, SkReduceOrder::kNo_Quadratics);
-        int order2 = reduce2.reduce(cubic2, SkReduceOrder::kNo_Quadratics);
+        int order1 = reduce1.reduce(c1, SkReduceOrder::kNo_Quadratics);
+        int order2 = reduce2.reduce(c2, SkReduceOrder::kNo_Quadratics);
         const bool showSkipped = false;
         if (order1 < 4) {
             if (showSkipped) {
@@ -38,7 +41,7 @@
             continue;
         }
         SkIntersections tIntersections;
-        tIntersections.intersect(cubic1, cubic2);
+        tIntersections.intersect(c1, c2);
         if (!tIntersections.used()) {
             if (showSkipped) {
                 SkDebugf("%s [%d] no intersection\n", __FUNCTION__, iIndex);
@@ -53,9 +56,9 @@
         }
         for (int pt = 0; pt < tIntersections.used(); ++pt) {
             double tt1 = tIntersections[0][pt];
-            SkDPoint xy1 = cubic1.ptAtT(tt1);
+            SkDPoint xy1 = c1.ptAtT(tt1);
             double tt2 = tIntersections[1][pt];
-            SkDPoint xy2 = cubic2.ptAtT(tt2);
+            SkDPoint xy2 = c2.ptAtT(tt2);
             if (!xy1.approximatelyEqual(xy2)) {
                 SkDebugf("%s [%d,%d] x!= t1=%g (%g,%g) t2=%g (%g,%g)\n",
                     __FUNCTION__, (int)index, pt, tt1, xy1.fX, xy1.fY, tt2, xy2.fX, xy2.fY);
@@ -66,7 +69,7 @@
     }
 }
 
-static const SkDCubic testSet[] = {
+static const CubicPts testSet[] = {
 // FIXME: uncommenting these two will cause this to fail
 // this results in two curves very nearly but not exactly coincident
 #if 0
@@ -164,7 +167,7 @@
 
 const int testSetCount = (int) SK_ARRAY_COUNT(testSet);
 
-static const SkDCubic newTestSet[] = {
+static const CubicPts newTestSet[] = {
 { { { 130.0427549999999997, 11417.41309999999976 },{ 130.2331240000000037, 11418.3192999999992 },{ 131.0370790000000056, 11419 },{ 132, 11419 } } },
 { { { 132, 11419 },{ 130.8954319999999996, 11419 },{ 130, 11418.10449999999946 },{ 130, 11417 } } },
     
@@ -381,10 +384,13 @@
 };
 
 const int newTestSetCount = (int) SK_ARRAY_COUNT(newTestSet);
-static void oneOff(skiatest::Reporter* reporter, const SkDCubic& cubic1, const SkDCubic& cubic2,
+static void oneOff(skiatest::Reporter* reporter, const CubicPts& cubic1, const CubicPts& cubic2,
         bool coin) {
-    SkASSERT(ValidCubic(cubic1));
-    SkASSERT(ValidCubic(cubic2));
+    SkDCubic c1, c2;
+    c1.debugSet(cubic1.fPts);
+    c2.debugSet(cubic2.fPts);
+    SkASSERT(ValidCubic(c1));
+    SkASSERT(ValidCubic(c2));
 #if ONE_OFF_DEBUG
     SkDebugf("computed quadratics given\n");
     SkDebugf("  {{%1.9g,%1.9g}, {%1.9g,%1.9g}, {%1.9g,%1.9g}, {%1.9g,%1.9g}},\n",
@@ -395,7 +401,7 @@
         cubic2[2].fX, cubic2[2].fY, cubic2[3].fX, cubic2[3].fY);
 #endif
     SkIntersections intersections;
-    intersections.intersect(cubic1, cubic2);
+    intersections.intersect(c1, c2);
 #if DEBUG_T_SECT_DUMP == 3
     SkDebugf("</div>\n\n");
     SkDebugf("<script type=\"text/javascript\">\n\n");
@@ -412,9 +418,9 @@
     SkDPoint xy1, xy2;
     for (int pt3 = 0; pt3 < intersections.used(); ++pt3) {
         tt1 = intersections[0][pt3];
-        xy1 = cubic1.ptAtT(tt1);
+        xy1 = c1.ptAtT(tt1);
         tt2 = intersections[1][pt3];
-        xy2 = cubic2.ptAtT(tt2);
+        xy2 = c2.ptAtT(tt2);
         const SkDPoint& iPt = intersections.pt(pt3);
 #if ONE_OFF_DEBUG
         SkDebugf("%s t1=%1.9g (%1.9g, %1.9g) (%1.9g, %1.9g) (%1.9g, %1.9g) t2=%1.9g\n",
@@ -429,20 +435,20 @@
 }
 
 static void oneOff(skiatest::Reporter* reporter, int outer, int inner) {
-    const SkDCubic& cubic1 = testSet[outer];
-    const SkDCubic& cubic2 = testSet[inner];
+    const CubicPts& cubic1 = testSet[outer];
+    const CubicPts& cubic2 = testSet[inner];
     oneOff(reporter, cubic1, cubic2, false);
 }
 
 static void newOneOff(skiatest::Reporter* reporter, int outer, int inner) {
-    const SkDCubic& cubic1 = newTestSet[outer];
-    const SkDCubic& cubic2 = newTestSet[inner];
+    const CubicPts& cubic1 = newTestSet[outer];
+    const CubicPts& cubic2 = newTestSet[inner];
     oneOff(reporter, cubic1, cubic2, false);
 }
 
 static void testsOneOff(skiatest::Reporter* reporter, int index) {
-    const SkDCubic& cubic1 = tests[index][0];
-    const SkDCubic& cubic2 = tests[index][1];
+    const CubicPts& cubic1 = tests[index][0];
+    const CubicPts& cubic2 = tests[index][1];
     oneOff(reporter, cubic1, cubic2, false);
 }
 
@@ -468,12 +474,12 @@
     unsigned seed = 0;
 #endif
     for (int test = 0; test < tests; ++test) {
-        SkDCubic cubic1, cubic2;
+        CubicPts cubic1, cubic2;
         for (int i = 0; i < 4; ++i) {
-            cubic1[i].fX = static_cast<double>(SK_RAND(seed)) / RAND_MAX * 100;
-            cubic1[i].fY = static_cast<double>(SK_RAND(seed)) / RAND_MAX * 100;
-            cubic2[i].fX = static_cast<double>(SK_RAND(seed)) / RAND_MAX * 100;
-            cubic2[i].fY = static_cast<double>(SK_RAND(seed)) / RAND_MAX * 100;
+            cubic1.fPts[i].fX = static_cast<double>(SK_RAND(seed)) / RAND_MAX * 100;
+            cubic1.fPts[i].fY = static_cast<double>(SK_RAND(seed)) / RAND_MAX * 100;
+            cubic2.fPts[i].fX = static_cast<double>(SK_RAND(seed)) / RAND_MAX * 100;
+            cubic2.fPts[i].fY = static_cast<double>(SK_RAND(seed)) / RAND_MAX * 100;
         }
     #if DEBUG_CRASH
         char str[1024];
@@ -486,15 +492,18 @@
                 cubic2[3].fX, cubic2[3].fY);
     #endif
         SkDRect rect1, rect2;
-        rect1.setBounds(cubic1);
-        rect2.setBounds(cubic2);
+        SkDCubic c1, c2;
+        c1.debugSet(cubic1.fPts);
+        c2.debugSet(cubic2.fPts);
+        rect1.setBounds(c1);
+        rect2.setBounds(c2);
         bool boundsIntersect = rect1.fLeft <= rect2.fRight && rect2.fLeft <= rect2.fRight
                 && rect1.fTop <= rect2.fBottom && rect2.fTop <= rect1.fBottom;
         if (test == -1) {
             SkDebugf("ready...\n");
         }
         SkIntersections intersections2;
-        int newIntersects = intersections2.intersect(cubic1, cubic2);
+        int newIntersects = intersections2.intersect(c1, c2);
         if (!boundsIntersect && newIntersects) {
     #if DEBUG_CRASH
             SkDebugf("%s %d unexpected intersection boundsIntersect=%d "
@@ -505,9 +514,9 @@
         }
         for (int pt = 0; pt < intersections2.used(); ++pt) {
             double tt1 = intersections2[0][pt];
-            SkDPoint xy1 = cubic1.ptAtT(tt1);
+            SkDPoint xy1 = c1.ptAtT(tt1);
             double tt2 = intersections2[1][pt];
-            SkDPoint xy2 = cubic2.ptAtT(tt2);
+            SkDPoint xy2 = c2.ptAtT(tt2);
             REPORTER_ASSERT(reporter, xy1.approximatelyEqual(xy2));
         }
         reporter->bumpTestCount();
@@ -516,17 +525,20 @@
 
 static void intersectionFinder(int index0, int index1, double t1Seed, double t2Seed,
         double t1Step, double t2Step) {
-    const SkDCubic& cubic1 = newTestSet[index0];
-    const SkDCubic& cubic2 = newTestSet[index1];
+    const CubicPts& cubic1 = newTestSet[index0];
+    const CubicPts& cubic2 = newTestSet[index1];
     SkDPoint t1[3], t2[3];
     bool toggle = true;
+    SkDCubic c1, c2;
+    c1.debugSet(cubic1.fPts);
+    c2.debugSet(cubic2.fPts);
     do {
-        t1[0] = cubic1.ptAtT(t1Seed - t1Step);
-        t1[1] = cubic1.ptAtT(t1Seed);
-        t1[2] = cubic1.ptAtT(t1Seed + t1Step);
-        t2[0] = cubic2.ptAtT(t2Seed - t2Step);
-        t2[1] = cubic2.ptAtT(t2Seed);
-        t2[2] = cubic2.ptAtT(t2Seed + t2Step);
+        t1[0] = c1.ptAtT(t1Seed - t1Step);
+        t1[1] = c1.ptAtT(t1Seed);
+        t1[2] = c1.ptAtT(t1Seed + t1Step);
+        t2[0] = c2.ptAtT(t2Seed - t2Step);
+        t2[1] = c2.ptAtT(t2Seed);
+        t2[2] = c2.ptAtT(t2Seed + t2Step);
         double dist[3][3];
         dist[1][1] = t1[1].distance(t2[1]);
         int best_i = 1, best_j = 1;
@@ -567,38 +579,38 @@
     double t22 = t2Seed + t2Step * 2;
     SkDPoint test;
     while (!approximately_zero(t1Step)) {
-        test = cubic1.ptAtT(t10);
+        test = c1.ptAtT(t10);
         t10 += t1[1].approximatelyEqual(test) ? -t1Step : t1Step;
         t1Step /= 2;
     }
     t1Step = 0.1;
     while (!approximately_zero(t1Step)) {
-        test = cubic1.ptAtT(t12);
+        test = c1.ptAtT(t12);
         t12 -= t1[1].approximatelyEqual(test) ? -t1Step : t1Step;
         t1Step /= 2;
     }
     while (!approximately_zero(t2Step)) {
-        test = cubic2.ptAtT(t20);
+        test = c2.ptAtT(t20);
         t20 += t2[1].approximatelyEqual(test) ? -t2Step : t2Step;
         t2Step /= 2;
     }
     t2Step = 0.1;
     while (!approximately_zero(t2Step)) {
-        test = cubic2.ptAtT(t22);
+        test = c2.ptAtT(t22);
         t22 -= t2[1].approximatelyEqual(test) ? -t2Step : t2Step;
         t2Step /= 2;
     }
 #if ONE_OFF_DEBUG
     SkDebugf("%s t1=(%1.9g<%1.9g<%1.9g) t2=(%1.9g<%1.9g<%1.9g)\n", __FUNCTION__,
         t10, t1Seed, t12, t20, t2Seed, t22);
-    SkDPoint p10 = cubic1.ptAtT(t10);
-    SkDPoint p1Seed = cubic1.ptAtT(t1Seed);
-    SkDPoint p12 = cubic1.ptAtT(t12);
+    SkDPoint p10 = c1.ptAtT(t10);
+    SkDPoint p1Seed = c1.ptAtT(t1Seed);
+    SkDPoint p12 = c1.ptAtT(t12);
     SkDebugf("%s p1=(%1.9g,%1.9g)<(%1.9g,%1.9g)<(%1.9g,%1.9g)\n", __FUNCTION__,
         p10.fX, p10.fY, p1Seed.fX, p1Seed.fY, p12.fX, p12.fY);
-    SkDPoint p20 = cubic2.ptAtT(t20);
-    SkDPoint p2Seed = cubic2.ptAtT(t2Seed);
-    SkDPoint p22 = cubic2.ptAtT(t22);
+    SkDPoint p20 = c2.ptAtT(t20);
+    SkDPoint p2Seed = c2.ptAtT(t2Seed);
+    SkDPoint p22 = c2.ptAtT(t22);
     SkDebugf("%s p2=(%1.9g,%1.9g)<(%1.9g,%1.9g)<(%1.9g,%1.9g)\n", __FUNCTION__,
         p20.fX, p20.fY, p2Seed.fX, p2Seed.fY, p22.fX, p22.fY);
 #endif
@@ -614,7 +626,7 @@
     intersectionFinder(0, 1, 0.865213351, 0.865208087, t1Step, t2Step);
 }
 
-static const SkDCubic selfSet[] = {
+static const CubicPts selfSet[] = {
     {{{2, 3}, {0, 4}, {3, 2}, {5, 3}}},
     {{{3, 6}, {2, 3}, {4, 0}, {3, 2}}},
     {{{0, 2}, {2, 3}, {5, 1}, {3, 2}}},
@@ -628,10 +640,10 @@
 int selfSetCount = (int) SK_ARRAY_COUNT(selfSet);
 
 static void selfOneOff(skiatest::Reporter* reporter, int index) {
-    const SkDCubic& cubic = selfSet[index];
+    const CubicPts& cubic = selfSet[index];
     SkPoint c[4];
     for (int i = 0; i < 4; ++i) {
-        c[i] = cubic[i].asSkPoint();
+        c[i] = cubic.fPts[i].asSkPoint();
     }
     SkScalar loopT;
     SkScalar d[3];
@@ -662,7 +674,7 @@
     }
 }
 
-static const SkDCubic coinSet[] = {
+static const CubicPts coinSet[] = {
     {{{72.350448608398438, 27.966041564941406}, {72.58441162109375, 27.861515045166016},
         {72.818222045898437, 27.756658554077148}, {73.394996643066406, 27.49799919128418}}},
     {{{73.394996643066406, 27.49799919128418}, {72.818222045898437, 27.756658554077148},
@@ -684,8 +696,8 @@
 static int coinSetCount = (int) SK_ARRAY_COUNT(coinSet);
 
 static void coinOneOff(skiatest::Reporter* reporter, int index) {
-    const SkDCubic& cubic1 = coinSet[index];
-    const SkDCubic& cubic2 = coinSet[index + 1];
+    const CubicPts& cubic1 = coinSet[index];
+    const CubicPts& cubic2 = coinSet[index + 1];
     oneOff(reporter, cubic1, cubic2, true);
 }