test: augment the half precision numbers testsuite.

test/half.cpp

@@ -28,7 +28,13 @@ class HalfTest : public CppUnit::TestCase
     CPPUNIT_TEST(test_half_makebits);
     CPPUNIT_TEST(test_half_makeslow);
     CPPUNIT_TEST(test_half_makefast);
+    CPPUNIT_TEST(test_half_isnan);
+    CPPUNIT_TEST(test_half_isinf);
+    CPPUNIT_TEST(test_half_isfinite);
+    CPPUNIT_TEST(test_half_isnormal);
+    CPPUNIT_TEST(test_half_classify);
     CPPUNIT_TEST(test_half_to_float);
+    CPPUNIT_TEST(test_half_to_int);
     CPPUNIT_TEST_SUITE_END();
 
 public:
@@ -52,53 +58,175 @@ public:
 
     void test_half_makeslow()
     {
-        for (size_t i = 0; i < 8; i++)
+        for (size_t i = 0; i < sizeof(pairs) / sizeof(*pairs); i++)
         {
-            half a = half::makeslow(array1[i].f);
-            uint16_t b = array1[i].x;
+            half a = half::makeslow(pairs[i].f);
+            uint16_t b = pairs[i].x;
             CPPUNIT_ASSERT_EQUAL(a.bits(), b);
         }
     }
 
     void test_half_makefast()
     {
-        for (size_t i = 0; i < 8; i++)
+        for (size_t i = 0; i < sizeof(pairs) / sizeof(*pairs); i++)
         {
-            half a = half::makefast(array1[i].f);
-            uint16_t b = array1[i].x;
+            half a = half::makefast(pairs[i].f);
+            uint16_t b = pairs[i].x;
             CPPUNIT_ASSERT_EQUAL(a.bits(), b);
         }
     }
 
+    void test_half_isnan()
+    {
+        CPPUNIT_ASSERT(half::makebits(0x7c01).isnan());
+        CPPUNIT_ASSERT(half::makebits(0xfc01).isnan());
+        CPPUNIT_ASSERT(half::makebits(0x7e00).isnan());
+        CPPUNIT_ASSERT(half::makebits(0xfe00).isnan());
+
+        CPPUNIT_ASSERT(!half::makebits(0x7c00).isnan());
+        CPPUNIT_ASSERT(!half::makebits(0xfc00).isnan());
+
+        CPPUNIT_ASSERT(!half(0.0f).isnan());
+        CPPUNIT_ASSERT(!half(-0.0f).isnan());
+        CPPUNIT_ASSERT(!half(2.0f).isnan());
+        CPPUNIT_ASSERT(!half(-2.0f).isnan());
+    }
+
+    void test_half_isinf()
+    {
+        CPPUNIT_ASSERT(half(65536.0f).isinf());
+        CPPUNIT_ASSERT(half(-65536.0f).isinf());
+
+        CPPUNIT_ASSERT(!half(0.0f).isinf());
+        CPPUNIT_ASSERT(!half(-0.0f).isinf());
+        CPPUNIT_ASSERT(!half(65535.0f).isinf());
+        CPPUNIT_ASSERT(!half(-65535.0f).isinf());
+
+        CPPUNIT_ASSERT(half::makebits(0x7c00).isinf());
+        CPPUNIT_ASSERT(half::makebits(0xfc00).isinf());
+
+        CPPUNIT_ASSERT(!half::makebits(0x7e00).isinf());
+        CPPUNIT_ASSERT(!half::makebits(0xfe00).isinf());
+    }
+
+    void test_half_isfinite()
+    {
+        CPPUNIT_ASSERT(half(0.0f).isfinite());
+        CPPUNIT_ASSERT(half(-0.0f).isfinite());
+        CPPUNIT_ASSERT(half(65535.0f).isfinite());
+        CPPUNIT_ASSERT(half(-65535.0f).isfinite());
+
+        CPPUNIT_ASSERT(!half(65536.0f).isfinite());
+        CPPUNIT_ASSERT(!half(-65536.0f).isfinite());
+
+        CPPUNIT_ASSERT(!half::makebits(0x7c00).isfinite());
+        CPPUNIT_ASSERT(!half::makebits(0xfc00).isfinite());
+
+        CPPUNIT_ASSERT(!half::makebits(0x7e00).isfinite());
+        CPPUNIT_ASSERT(!half::makebits(0xfe00).isfinite());
+    }
+
+    void test_half_isnormal()
+    {
+        CPPUNIT_ASSERT(half(0.0f).isnormal());
+        CPPUNIT_ASSERT(half(-0.0f).isnormal());
+        CPPUNIT_ASSERT(half(65535.0f).isnormal());
+        CPPUNIT_ASSERT(half(-65535.0f).isnormal());
+
+        CPPUNIT_ASSERT(!half(65536.0f).isnormal());
+        CPPUNIT_ASSERT(!half(-65536.0f).isnormal());
+
+        CPPUNIT_ASSERT(!half::makebits(0x7c00).isnormal());
+        CPPUNIT_ASSERT(!half::makebits(0xfc00).isnormal());
+
+        CPPUNIT_ASSERT(!half::makebits(0x7e00).isnormal());
+        CPPUNIT_ASSERT(!half::makebits(0xfe00).isnormal());
+    }
+
+    void test_half_classify()
+    {
+        for (uint32_t i = 0; i < 0x10000; i++)
+        {
+            half h = half::makebits(i);
+            if (h.isnan())
+            {
+                CPPUNIT_ASSERT(!h.isinf());
+                CPPUNIT_ASSERT(!h.isnormal());
+                CPPUNIT_ASSERT(!h.isfinite());
+            }
+            else if (h.isinf())
+            {
+                CPPUNIT_ASSERT(!h.isnormal());
+                CPPUNIT_ASSERT(!h.isfinite());
+            }
+            else
+            {
+                CPPUNIT_ASSERT(h.isfinite());
+            }
+        }
+    }
+
     void test_half_to_float()
     {
-#if 0
-        for (unsigned int i = 0; i < 0x10000; i++)
+        for (size_t i = 0; i < sizeof(pairs) / sizeof(*pairs); i++)
         {
-            half a = half::makebits(i);
-            half b = half::makefast((float)a);
-            //CPPUNIT_ASSERT_EQUAL(a.bits(), b.bits());
+            float a = (float)half::makebits(pairs[i].x);
+            float b = pairs[i].f;
+            CPPUNIT_ASSERT_EQUAL(a, b);
+        }
+
+        for (uint32_t i = 0; i < 0x10000; i++)
+        {
+            half h = half::makebits(i);
+            float f = (float)h;
+            half g = (half)f;
+            if (h.isnan())
+            {
+                CPPUNIT_ASSERT(isnan(f));
+                CPPUNIT_ASSERT(g.isnan());
+            }
+            else
+            {
+                CPPUNIT_ASSERT(!isnan(f));
+                CPPUNIT_ASSERT_EQUAL(g.bits(), h.bits());
+            }
         }
     }
-#endif
+
+    void test_half_to_int()
+    {
+        CPPUNIT_ASSERT_EQUAL((int)(half)(0.0f), 0);
+        CPPUNIT_ASSERT_EQUAL((int)(half)(-0.0f), 0);
+        CPPUNIT_ASSERT_EQUAL((int)(half)(0.9f), 0);
+        CPPUNIT_ASSERT_EQUAL((int)(half)(-0.9f), 0);
+        CPPUNIT_ASSERT_EQUAL((int)(half)(1.0f), 1);
+        CPPUNIT_ASSERT_EQUAL((int)(half)(-1.0f), -1);
+        CPPUNIT_ASSERT_EQUAL((int)(half)(1.9f), 1);
+        CPPUNIT_ASSERT_EQUAL((int)(half)(-1.9f), -1);
+        CPPUNIT_ASSERT_EQUAL((int)(half)(65504.0f), 65504);
+        CPPUNIT_ASSERT_EQUAL((int)(half)(-65504.0f), -65504);
     }
 
 private:
     struct TestPair { float f; uint16_t x; };
 
-    static TestPair const array1[];
+    static TestPair const pairs[11];
 };
 
-HalfTest::TestPair const HalfTest::array1[] =
+HalfTest::TestPair const HalfTest::pairs[] =
 {
-    { 0.0f,     0x0000 },
-    { -0.0f,    0x8000 },
-    { 1.0f,     0x3c00 },
-    { -1.0f,    0xbc00 },
-    { 2.0f,     0x4000 },
-    { 0.5f,     0x3800 },
-    { 0.125f,   0x3000 },
-    { 15.9375f, 0x4bf8 },
+    /* All these values have exact half representations */
+    { 0.0f,      0x0000 },
+    { -0.0f,     0x8000 }, /* negative zero */
+    { 1.0f,      0x3c00 },
+    { -1.0f,     0xbc00 },
+    { 2.0f,      0x4000 },
+    { 0.5f,      0x3800 },
+    { 0.125f,    0x3000 },
+    { 15.9375f,  0x4bf8 },
+    { 0x1.fp-10, 0x17c0 },
+    { 0x1.fp-14, 0x07c0 }, /* denormal */
+    { 0x1.fp-15, 0x03e0 }, /* denormal */
 };
 
 CPPUNIT_TEST_SUITE_REGISTRATION(HalfTest);

test/lol-bench.cpp

@@ -22,8 +22,19 @@ int main(int argc, char **argv)
 {
     Timer timer;
 
+    float ftotal = 0.0f;
+    for (uint32_t i = 0; i < 0xffffffffu; i += 7)
+    {
+        union { float f; uint32_t x; } u;
+        u.x = i;
+
+        float h = (float)half::makefast(u.f);
+        ftotal += h;
+    }
+    Log::Info("time for makeslow: %f (hash %f)\n", timer.GetMs(), ftotal);
+
     uint16_t total = 0;
-    for (uint32_t i = 0; i < 0xffffffffu; i++)
+    for (uint32_t i = 0; i < 0xffffffffu; i += 7)
     {
         union { float f; uint32_t x; } u;
         u.x = i;
@@ -33,7 +44,7 @@ int main(int argc, char **argv)
     }
     Log::Info("time for makeslow: %f (hash %04x)\n", timer.GetMs(), total);
 
-    for (uint32_t i = 0; i < 0xffffffffu; i++)
+    for (uint32_t i = 0; i < 0xffffffffu; i += 7)
     {
         union { float f; uint32_t x; } u;
         u.x = i;