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-rw-r--r--lib/std/math/sin.zig168
1 files changed, 0 insertions, 168 deletions
diff --git a/lib/std/math/sin.zig b/lib/std/math/sin.zig
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index cf663b1d9e..0000000000
--- a/lib/std/math/sin.zig
+++ /dev/null
@@ -1,168 +0,0 @@
-// Ported from musl, which is licensed under the MIT license:
-// https://git.musl-libc.org/cgit/musl/tree/COPYRIGHT
-//
-// https://git.musl-libc.org/cgit/musl/tree/src/math/sinf.c
-// https://git.musl-libc.org/cgit/musl/tree/src/math/sin.c
-//
-const std = @import("../std.zig");
-const math = std.math;
-const expect = std.testing.expect;
-
-const kernel = @import("__trig.zig");
-const __rem_pio2 = @import("__rem_pio2.zig").__rem_pio2;
-const __rem_pio2f = @import("__rem_pio2f.zig").__rem_pio2f;
-
-/// Returns the sine of the radian value x.
-///
-/// Special Cases:
-/// - sin(+-0) = +-0
-/// - sin(+-inf) = nan
-/// - sin(nan) = nan
-pub fn sin(x: anytype) @TypeOf(x) {
- const T = @TypeOf(x);
- return switch (T) {
- f32 => sin32(x),
- f64 => sin64(x),
- else => @compileError("sin not implemented for " ++ @typeName(T)),
- };
-}
-
-fn sin32(x: f32) f32 {
- // Small multiples of pi/2 rounded to double precision.
- const s1pio2: f64 = 1.0 * math.pi / 2.0; // 0x3FF921FB, 0x54442D18
- const s2pio2: f64 = 2.0 * math.pi / 2.0; // 0x400921FB, 0x54442D18
- const s3pio2: f64 = 3.0 * math.pi / 2.0; // 0x4012D97C, 0x7F3321D2
- const s4pio2: f64 = 4.0 * math.pi / 2.0; // 0x401921FB, 0x54442D18
-
- var ix = @bitCast(u32, x);
- const sign = ix >> 31 != 0;
- ix &= 0x7fffffff;
-
- if (ix <= 0x3f490fda) { // |x| ~<= pi/4
- if (ix < 0x39800000) { // |x| < 2**-12
- // raise inexact if x!=0 and underflow if subnormal
- math.doNotOptimizeAway(if (ix < 0x00800000) x / 0x1p120 else x + 0x1p120);
- return x;
- }
- return kernel.__sindf(x);
- }
- if (ix <= 0x407b53d1) { // |x| ~<= 5*pi/4
- if (ix <= 0x4016cbe3) { // |x| ~<= 3pi/4
- if (sign) {
- return -kernel.__cosdf(x + s1pio2);
- } else {
- return kernel.__cosdf(x - s1pio2);
- }
- }
- return kernel.__sindf(if (sign) -(x + s2pio2) else -(x - s2pio2));
- }
- if (ix <= 0x40e231d5) { // |x| ~<= 9*pi/4
- if (ix <= 0x40afeddf) { // |x| ~<= 7*pi/4
- if (sign) {
- return kernel.__cosdf(x + s3pio2);
- } else {
- return -kernel.__cosdf(x - s3pio2);
- }
- }
- return kernel.__sindf(if (sign) x + s4pio2 else x - s4pio2);
- }
-
- // sin(Inf or NaN) is NaN
- if (ix >= 0x7f800000) {
- return x - x;
- }
-
- var y: f64 = undefined;
- const n = __rem_pio2f(x, &y);
- return switch (n & 3) {
- 0 => kernel.__sindf(y),
- 1 => kernel.__cosdf(y),
- 2 => kernel.__sindf(-y),
- else => -kernel.__cosdf(y),
- };
-}
-
-fn sin64(x: f64) f64 {
- var ix = @bitCast(u64, x) >> 32;
- ix &= 0x7fffffff;
-
- // |x| ~< pi/4
- if (ix <= 0x3fe921fb) {
- if (ix < 0x3e500000) { // |x| < 2**-26
- // raise inexact if x != 0 and underflow if subnormal
- math.doNotOptimizeAway(if (ix < 0x00100000) x / 0x1p120 else x + 0x1p120);
- return x;
- }
- return kernel.__sin(x, 0.0, 0);
- }
-
- // sin(Inf or NaN) is NaN
- if (ix >= 0x7ff00000) {
- return x - x;
- }
-
- var y: [2]f64 = undefined;
- const n = __rem_pio2(x, &y);
- return switch (n & 3) {
- 0 => kernel.__sin(y[0], y[1], 1),
- 1 => kernel.__cos(y[0], y[1]),
- 2 => -kernel.__sin(y[0], y[1], 1),
- else => -kernel.__cos(y[0], y[1]),
- };
-}
-
-test "math.sin" {
- try expect(sin(@as(f32, 0.0)) == sin32(0.0));
- try expect(sin(@as(f64, 0.0)) == sin64(0.0));
- try expect(comptime (math.sin(@as(f64, 2))) == math.sin(@as(f64, 2)));
-}
-
-test "math.sin32" {
- const epsilon = 0.00001;
-
- try expect(math.approxEqAbs(f32, sin32(0.0), 0.0, epsilon));
- try expect(math.approxEqAbs(f32, sin32(0.2), 0.198669, epsilon));
- try expect(math.approxEqAbs(f32, sin32(0.8923), 0.778517, epsilon));
- try expect(math.approxEqAbs(f32, sin32(1.5), 0.997495, epsilon));
- try expect(math.approxEqAbs(f32, sin32(-1.5), -0.997495, epsilon));
- try expect(math.approxEqAbs(f32, sin32(37.45), -0.246544, epsilon));
- try expect(math.approxEqAbs(f32, sin32(89.123), 0.916166, epsilon));
-}
-
-test "math.sin64" {
- const epsilon = 0.000001;
-
- try expect(math.approxEqAbs(f64, sin64(0.0), 0.0, epsilon));
- try expect(math.approxEqAbs(f64, sin64(0.2), 0.198669, epsilon));
- try expect(math.approxEqAbs(f64, sin64(0.8923), 0.778517, epsilon));
- try expect(math.approxEqAbs(f64, sin64(1.5), 0.997495, epsilon));
- try expect(math.approxEqAbs(f64, sin64(-1.5), -0.997495, epsilon));
- try expect(math.approxEqAbs(f64, sin64(37.45), -0.246543, epsilon));
- try expect(math.approxEqAbs(f64, sin64(89.123), 0.916166, epsilon));
-}
-
-test "math.sin32.special" {
- try expect(sin32(0.0) == 0.0);
- try expect(sin32(-0.0) == -0.0);
- try expect(math.isNan(sin32(math.inf(f32))));
- try expect(math.isNan(sin32(-math.inf(f32))));
- try expect(math.isNan(sin32(math.nan(f32))));
-}
-
-test "math.sin64.special" {
- try expect(sin64(0.0) == 0.0);
- try expect(sin64(-0.0) == -0.0);
- try expect(math.isNan(sin64(math.inf(f64))));
- try expect(math.isNan(sin64(-math.inf(f64))));
- try expect(math.isNan(sin64(math.nan(f64))));
-}
-
-test "math.sin32 #9901" {
- const float = @bitCast(f32, @as(u32, 0b11100011111111110000000000000000));
- _ = std.math.sin(float);
-}
-
-test "math.sin64 #9901" {
- const float = @bitCast(f64, @as(u64, 0b1111111101000001000000001111110111111111100000000000000000000001));
- _ = std.math.sin(float);
-}