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3 // modification, are permitted provided that the following conditions are
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28 // Tests that the --fast-math implementation of Math.exp() has
29 // reasonable precision.
35 var first_call_result = exp(Math.PI);
36 var second_call_result = exp(Math.PI);
38 function assertAlmostEquals(expected, actual, x) {
39 if (expected == 0 && actual == 0) return; // OK
40 if (expected == Number.POSITIVE_INFINITY &&
41 actual == Number.POSITIVE_INFINITY) {
44 relative_diff = Math.abs(expected/actual - 1);
45 assertTrue(relative_diff < 1e-12, "relative difference of " + relative_diff +
49 var increment = Math.PI / 35; // Roughly 0.1, but we want to try many
50 // different mantissae.
51 for (var x = -708; x < 710; x += increment) {
53 var reference = Math.pow(Math.E, x);
54 assertAlmostEquals(reference, ex, x);
55 if (ex > 0 && isFinite(ex)) {
56 var back = Math.log(ex);
57 assertAlmostEquals(x, back, x + " (backwards)");
61 // Make sure optimizing the function does not alter the result.
62 var last_call_result = exp(Math.PI);
63 assertEquals(first_call_result, second_call_result);
64 assertEquals(first_call_result, last_call_result);