summaryrefslogtreecommitdiff
path: root/src/pal/tests/palsuite/c_runtime/sqrt/test1/test1.cpp
diff options
context:
space:
mode:
Diffstat (limited to 'src/pal/tests/palsuite/c_runtime/sqrt/test1/test1.cpp')
-rw-r--r--src/pal/tests/palsuite/c_runtime/sqrt/test1/test1.cpp123
1 files changed, 123 insertions, 0 deletions
diff --git a/src/pal/tests/palsuite/c_runtime/sqrt/test1/test1.cpp b/src/pal/tests/palsuite/c_runtime/sqrt/test1/test1.cpp
new file mode 100644
index 0000000..62d2251
--- /dev/null
+++ b/src/pal/tests/palsuite/c_runtime/sqrt/test1/test1.cpp
@@ -0,0 +1,123 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+/*=====================================================================
+**
+** Source: test1.c
+**
+** Purpose: Call the sqrt function on a positive value, a positive value
+** with a decimal and on the maxium possible double value.
+**
+**
+**===================================================================*/
+
+#include <palsuite.h>
+
+// binary64 (double) has a machine epsilon of 2^-52 (approx. 2.22e-16). However, this
+// is slightly too accurate when writing tests meant to run against libm implementations
+// for various platforms. 2^-50 (approx. 8.88e-16) seems to be as accurate as we can get.
+//
+// The tests themselves will take PAL_EPSILON and adjust it according to the expected result
+// so that the delta used for comparison will compare the most significant digits and ignore
+// any digits that are outside the double precision range (15-17 digits).
+
+// For example, a test with an expect result in the format of 0.xxxxxxxxxxxxxxxxx will use
+// PAL_EPSILON for the variance, while an expected result in the format of 0.0xxxxxxxxxxxxxxxxx
+// will use PAL_EPSILON / 10 and and expected result in the format of x.xxxxxxxxxxxxxxxx will
+// use PAL_EPSILON * 10.
+#define PAL_EPSILON 8.8817841970012523e-16
+
+#define PAL_NAN sqrt(-1.0)
+#define PAL_POSINF -log(0.0)
+#define PAL_NEGINF log(0.0)
+
+/**
+ * Helper test structure
+ */
+struct test
+{
+ double value; /* value to test the function with */
+ double expected; /* expected result */
+ double variance; /* maximum delta between the expected and actual result */
+};
+
+/**
+ * validate
+ *
+ * test validation function
+ */
+void __cdecl validate(double value, double expected, double variance)
+{
+ double result = sqrt(value);
+
+ /*
+ * The test is valid when the difference between result
+ * and expected is less than or equal to variance
+ */
+ double delta = fabs(result - expected);
+
+ if (delta > variance)
+ {
+ Fail("sqrt(%g) returned %20.17g when it should have returned %20.17g",
+ value, result, expected);
+ }
+}
+
+/**
+ * validate
+ *
+ * test validation function for values returning NaN
+ */
+void __cdecl validate_isnan(double value)
+{
+ double result = sqrt(value);
+
+ if (!_isnan(result))
+ {
+ Fail("sqrt(%g) returned %20.17g when it should have returned %20.17g",
+ value, result, PAL_NAN);
+ }
+}
+
+int __cdecl main(int argc, char **argv)
+{
+ struct test tests[] =
+ {
+ /* value expected variance */
+ { 0.31830988618379067, 0.56418958354775629, PAL_EPSILON }, // value: 1 / pi
+ { 0.43429448190325183, 0.65901022898226081, PAL_EPSILON }, // value: log10(e)
+ { 0.63661977236758134, 0.79788456080286536, PAL_EPSILON }, // value: 2 / pi
+ { 0.69314718055994531, 0.83255461115769776, PAL_EPSILON }, // value: ln(2)
+ { 0.70710678118654752, 0.84089641525371454, PAL_EPSILON }, // value: 1 / sqrt(2)
+ { 0.78539816339744831, 0.88622692545275801, PAL_EPSILON }, // value: pi / 4
+ { 1, 1, PAL_EPSILON * 10 },
+ { 1.1283791670955126, 1.0622519320271969, PAL_EPSILON * 10 }, // value: 2 / sqrt(pi)
+ { 1.4142135623730950, 1.1892071150027211, PAL_EPSILON * 10 }, // value: sqrt(2)
+ { 1.4426950408889634, 1.2011224087864498, PAL_EPSILON * 10 }, // value: log2(e)
+ { 1.5707963267948966, 1.2533141373155003, PAL_EPSILON * 10 }, // value: pi / 2
+ { 2.3025850929940457, 1.5174271293851464, PAL_EPSILON * 10 }, // value: ln(10)
+ { 2.7182818284590452, 1.6487212707001281, PAL_EPSILON * 10 }, // value: e
+ { 3.1415926535897932, 1.7724538509055160, PAL_EPSILON * 10 }, // value: pi
+ };
+
+ /* PAL initialization */
+ if (PAL_Initialize(argc, argv) != 0)
+ {
+ return FAIL;
+ }
+
+ validate(-0.0, -0.0, PAL_EPSILON);
+ validate( 0.0, 0.0, PAL_EPSILON);
+
+ for (int i = 0; i < (sizeof(tests) / sizeof(struct test)); i++)
+ {
+ validate(tests[i].value, tests[i].expected, tests[i].variance);
+ validate_isnan(-tests[i].value);
+ }
+
+ validate_isnan(PAL_NAN);
+
+ PAL_Terminate();
+ return PASS;
+}