master
1// Ported from musl, which is licensed under the MIT license:
2// https://git.musl-libc.org/cgit/musl/tree/COPYRIGHT
3//
4// https://git.musl-libc.org/cgit/musl/tree/src/math/exp2f.c
5// https://git.musl-libc.org/cgit/musl/tree/src/math/exp2.c
6
7const std = @import("std");
8const builtin = @import("builtin");
9const arch = builtin.cpu.arch;
10const math = std.math;
11const mem = std.mem;
12const expect = std.testing.expect;
13const expectEqual = std.testing.expectEqual;
14const common = @import("common.zig");
15
16pub const panic = common.panic;
17
18comptime {
19 @export(&__exp2h, .{ .name = "__exp2h", .linkage = common.linkage, .visibility = common.visibility });
20 @export(&exp2f, .{ .name = "exp2f", .linkage = common.linkage, .visibility = common.visibility });
21 @export(&exp2, .{ .name = "exp2", .linkage = common.linkage, .visibility = common.visibility });
22 @export(&__exp2x, .{ .name = "__exp2x", .linkage = common.linkage, .visibility = common.visibility });
23 if (common.want_ppc_abi) {
24 @export(&exp2q, .{ .name = "exp2f128", .linkage = common.linkage, .visibility = common.visibility });
25 }
26 @export(&exp2q, .{ .name = "exp2q", .linkage = common.linkage, .visibility = common.visibility });
27 @export(&exp2l, .{ .name = "exp2l", .linkage = common.linkage, .visibility = common.visibility });
28}
29
30pub fn __exp2h(x: f16) callconv(.c) f16 {
31 // TODO: more efficient implementation
32 return @floatCast(exp2f(x));
33}
34
35pub fn exp2f(x: f32) callconv(.c) f32 {
36 const tblsiz: u32 = @intCast(exp2ft.len);
37 const redux: f32 = 0x1.8p23 / @as(f32, @floatFromInt(tblsiz));
38 const P1: f32 = 0x1.62e430p-1;
39 const P2: f32 = 0x1.ebfbe0p-3;
40 const P3: f32 = 0x1.c6b348p-5;
41 const P4: f32 = 0x1.3b2c9cp-7;
42
43 const u: u32 = @bitCast(x);
44 const ix = u & 0x7FFFFFFF;
45
46 // |x| > 126
47 if (ix > 0x42FC0000) {
48 // nan
49 if (ix > 0x7F800000) {
50 return x;
51 }
52 // x >= 128
53 if (u >= 0x43000000 and u < 0x80000000) {
54 return x * 0x1.0p127;
55 }
56 // x < -126
57 if (u >= 0x80000000) {
58 if (u >= 0xC3160000 or u & 0x000FFFF != 0) {
59 if (common.want_float_exceptions) mem.doNotOptimizeAway(-0x1.0p-149 / x);
60 }
61 // x <= -150
62 if (u >= 0xC3160000) {
63 return 0;
64 }
65 }
66 }
67 // |x| <= 0x1p-25
68 else if (ix <= 0x33000000) {
69 return 1.0 + x;
70 }
71
72 // NOTE: musl relies on unsafe behaviours which are replicated below
73 // (addition/bit-shift overflow). Appears that this produces the
74 // intended result but should confirm how GCC/Clang handle this to ensure.
75
76 var uf = x + redux;
77 var i_0: u32 = @bitCast(uf);
78 i_0 +%= tblsiz / 2;
79
80 const k = i_0 / tblsiz;
81 const uk: f64 = @bitCast(@as(u64, 0x3FF + k) << 52);
82 i_0 &= tblsiz - 1;
83 uf -= redux;
84
85 const z: f64 = x - uf;
86 var r: f64 = exp2ft[@intCast(i_0)];
87 const t: f64 = r * z;
88 r = r + t * (P1 + z * P2) + t * (z * z) * (P3 + z * P4);
89 return @floatCast(r * uk);
90}
91
92pub fn exp2(x: f64) callconv(.c) f64 {
93 const tblsiz: u32 = @intCast(exp2dt.len / 2);
94 const redux: f64 = 0x1.8p52 / @as(f64, @floatFromInt(tblsiz));
95 const P1: f64 = 0x1.62e42fefa39efp-1;
96 const P2: f64 = 0x1.ebfbdff82c575p-3;
97 const P3: f64 = 0x1.c6b08d704a0a6p-5;
98 const P4: f64 = 0x1.3b2ab88f70400p-7;
99 const P5: f64 = 0x1.5d88003875c74p-10;
100
101 const ux: u64 = @bitCast(x);
102 const ix = @as(u32, @intCast(ux >> 32)) & 0x7FFFFFFF;
103
104 // TODO: This should be handled beneath.
105 if (math.isNan(x)) {
106 return math.nan(f64);
107 }
108
109 // |x| >= 1022 or nan
110 if (ix >= 0x408FF000) {
111 // x >= 1024 or nan
112 if (ix >= 0x40900000 and ux >> 63 == 0) {
113 math.raiseOverflow();
114 return math.inf(f64);
115 }
116 // -inf or -nan
117 if (ix >= 0x7FF00000) {
118 return -1 / x;
119 }
120 // x <= -1022
121 if (ux >> 63 != 0) {
122 // underflow
123 if (x <= -1075 or x - 0x1.0p52 + 0x1.0p52 != x) {
124 if (common.want_float_exceptions) mem.doNotOptimizeAway(@as(f32, @floatCast(-0x1.0p-149 / x)));
125 }
126 if (x <= -1075) {
127 return 0;
128 }
129 }
130 }
131 // |x| < 0x1p-54
132 else if (ix < 0x3C900000) {
133 return 1.0 + x;
134 }
135
136 // NOTE: musl relies on unsafe behaviours which are replicated below
137 // (addition overflow, division truncation, casting). Appears that this
138 // produces the intended result but should confirm how GCC/Clang handle this
139 // to ensure.
140
141 // reduce x
142 var uf: f64 = x + redux;
143 // NOTE: musl performs an implicit 64-bit to 32-bit u32 truncation here
144 var i_0: u32 = @truncate(@as(u64, @bitCast(uf)));
145 i_0 +%= tblsiz / 2;
146
147 const k: u32 = i_0 / tblsiz * tblsiz;
148 const ik: i32 = @divTrunc(@as(i32, @bitCast(k)), tblsiz);
149 i_0 %= tblsiz;
150 uf -= redux;
151
152 // r = exp2(y) = exp2t[i_0] * p(z - eps[i])
153 var z: f64 = x - uf;
154 const t: f64 = exp2dt[@intCast(2 * i_0)];
155 z -= exp2dt[@intCast(2 * i_0 + 1)];
156 const r: f64 = t + t * z * (P1 + z * (P2 + z * (P3 + z * (P4 + z * P5))));
157
158 return math.scalbn(r, ik);
159}
160
161pub fn __exp2x(x: f80) callconv(.c) f80 {
162 // TODO: more efficient implementation
163 return @floatCast(exp2q(x));
164}
165
166pub fn exp2q(x: f128) callconv(.c) f128 {
167 // TODO: more correct implementation
168 return exp2(@floatCast(x));
169}
170
171pub fn exp2l(x: c_longdouble) callconv(.c) c_longdouble {
172 switch (@typeInfo(c_longdouble).float.bits) {
173 16 => return __exp2h(x),
174 32 => return exp2f(x),
175 64 => return exp2(x),
176 80 => return __exp2x(x),
177 128 => return exp2q(x),
178 else => @compileError("unreachable"),
179 }
180}
181
182const exp2ft = [_]f64{
183 0x1.6a09e667f3bcdp-1,
184 0x1.7a11473eb0187p-1,
185 0x1.8ace5422aa0dbp-1,
186 0x1.9c49182a3f090p-1,
187 0x1.ae89f995ad3adp-1,
188 0x1.c199bdd85529cp-1,
189 0x1.d5818dcfba487p-1,
190 0x1.ea4afa2a490dap-1,
191 0x1.0000000000000p+0,
192 0x1.0b5586cf9890fp+0,
193 0x1.172b83c7d517bp+0,
194 0x1.2387a6e756238p+0,
195 0x1.306fe0a31b715p+0,
196 0x1.3dea64c123422p+0,
197 0x1.4bfdad5362a27p+0,
198 0x1.5ab07dd485429p+0,
199};
200
201const exp2dt = [_]f64{
202 // exp2(z + eps) eps
203 0x1.6a09e667f3d5dp-1, 0x1.9880p-44,
204 0x1.6b052fa751744p-1, 0x1.8000p-50,
205 0x1.6c012750bd9fep-1, -0x1.8780p-45,
206 0x1.6cfdcddd476bfp-1, 0x1.ec00p-46,
207 0x1.6dfb23c651a29p-1, -0x1.8000p-50,
208 0x1.6ef9298593ae3p-1, -0x1.c000p-52,
209 0x1.6ff7df9519386p-1, -0x1.fd80p-45,
210 0x1.70f7466f42da3p-1, -0x1.c880p-45,
211 0x1.71f75e8ec5fc3p-1, 0x1.3c00p-46,
212 0x1.72f8286eacf05p-1, -0x1.8300p-44,
213 0x1.73f9a48a58152p-1, -0x1.0c00p-47,
214 0x1.74fbd35d7ccfcp-1, 0x1.f880p-45,
215 0x1.75feb564267f1p-1, 0x1.3e00p-47,
216 0x1.77024b1ab6d48p-1, -0x1.7d00p-45,
217 0x1.780694fde5d38p-1, -0x1.d000p-50,
218 0x1.790b938ac1d00p-1, 0x1.3000p-49,
219 0x1.7a11473eb0178p-1, -0x1.d000p-49,
220 0x1.7b17b0976d060p-1, 0x1.0400p-45,
221 0x1.7c1ed0130c133p-1, 0x1.0000p-53,
222 0x1.7d26a62ff8636p-1, -0x1.6900p-45,
223 0x1.7e2f336cf4e3bp-1, -0x1.2e00p-47,
224 0x1.7f3878491c3e8p-1, -0x1.4580p-45,
225 0x1.80427543e1b4ep-1, 0x1.3000p-44,
226 0x1.814d2add1071ap-1, 0x1.f000p-47,
227 0x1.82589994ccd7ep-1, -0x1.1c00p-45,
228 0x1.8364c1eb942d0p-1, 0x1.9d00p-45,
229 0x1.8471a4623cab5p-1, 0x1.7100p-43,
230 0x1.857f4179f5bbcp-1, 0x1.2600p-45,
231 0x1.868d99b4491afp-1, -0x1.2c40p-44,
232 0x1.879cad931a395p-1, -0x1.3000p-45,
233 0x1.88ac7d98a65b8p-1, -0x1.a800p-45,
234 0x1.89bd0a4785800p-1, -0x1.d000p-49,
235 0x1.8ace5422aa223p-1, 0x1.3280p-44,
236 0x1.8be05bad619fap-1, 0x1.2b40p-43,
237 0x1.8cf3216b54383p-1, -0x1.ed00p-45,
238 0x1.8e06a5e08664cp-1, -0x1.0500p-45,
239 0x1.8f1ae99157807p-1, 0x1.8280p-45,
240 0x1.902fed0282c0ep-1, -0x1.cb00p-46,
241 0x1.9145b0b91ff96p-1, -0x1.5e00p-47,
242 0x1.925c353aa2ff9p-1, 0x1.5400p-48,
243 0x1.93737b0cdc64ap-1, 0x1.7200p-46,
244 0x1.948b82b5f98aep-1, -0x1.9000p-47,
245 0x1.95a44cbc852cbp-1, 0x1.5680p-45,
246 0x1.96bdd9a766f21p-1, -0x1.6d00p-44,
247 0x1.97d829fde4e2ap-1, -0x1.1000p-47,
248 0x1.98f33e47a23a3p-1, 0x1.d000p-45,
249 0x1.9a0f170ca0604p-1, -0x1.8a40p-44,
250 0x1.9b2bb4d53ff89p-1, 0x1.55c0p-44,
251 0x1.9c49182a3f15bp-1, 0x1.6b80p-45,
252 0x1.9d674194bb8c5p-1, -0x1.c000p-49,
253 0x1.9e86319e3238ep-1, 0x1.7d00p-46,
254 0x1.9fa5e8d07f302p-1, 0x1.6400p-46,
255 0x1.a0c667b5de54dp-1, -0x1.5000p-48,
256 0x1.a1e7aed8eb8f6p-1, 0x1.9e00p-47,
257 0x1.a309bec4a2e27p-1, 0x1.ad80p-45,
258 0x1.a42c980460a5dp-1, -0x1.af00p-46,
259 0x1.a5503b23e259bp-1, 0x1.b600p-47,
260 0x1.a674a8af46213p-1, 0x1.8880p-44,
261 0x1.a799e1330b3a7p-1, 0x1.1200p-46,
262 0x1.a8bfe53c12e8dp-1, 0x1.6c00p-47,
263 0x1.a9e6b5579fcd2p-1, -0x1.9b80p-45,
264 0x1.ab0e521356fb8p-1, 0x1.b700p-45,
265 0x1.ac36bbfd3f381p-1, 0x1.9000p-50,
266 0x1.ad5ff3a3c2780p-1, 0x1.4000p-49,
267 0x1.ae89f995ad2a3p-1, -0x1.c900p-45,
268 0x1.afb4ce622f367p-1, 0x1.6500p-46,
269 0x1.b0e07298db790p-1, 0x1.fd40p-45,
270 0x1.b20ce6c9a89a9p-1, 0x1.2700p-46,
271 0x1.b33a2b84f1a4bp-1, 0x1.d470p-43,
272 0x1.b468415b747e7p-1, -0x1.8380p-44,
273 0x1.b59728de5593ap-1, 0x1.8000p-54,
274 0x1.b6c6e29f1c56ap-1, 0x1.ad00p-47,
275 0x1.b7f76f2fb5e50p-1, 0x1.e800p-50,
276 0x1.b928cf22749b2p-1, -0x1.4c00p-47,
277 0x1.ba5b030a10603p-1, -0x1.d700p-47,
278 0x1.bb8e0b79a6f66p-1, 0x1.d900p-47,
279 0x1.bcc1e904bc1ffp-1, 0x1.2a00p-47,
280 0x1.bdf69c3f3a16fp-1, -0x1.f780p-46,
281 0x1.bf2c25bd71db8p-1, -0x1.0a00p-46,
282 0x1.c06286141b2e9p-1, -0x1.1400p-46,
283 0x1.c199bdd8552e0p-1, 0x1.be00p-47,
284 0x1.c2d1cd9fa64eep-1, -0x1.9400p-47,
285 0x1.c40ab5fffd02fp-1, -0x1.ed00p-47,
286 0x1.c544778fafd15p-1, 0x1.9660p-44,
287 0x1.c67f12e57d0cbp-1, -0x1.a100p-46,
288 0x1.c7ba88988c1b6p-1, -0x1.8458p-42,
289 0x1.c8f6d9406e733p-1, -0x1.a480p-46,
290 0x1.ca3405751c4dfp-1, 0x1.b000p-51,
291 0x1.cb720dcef9094p-1, 0x1.1400p-47,
292 0x1.ccb0f2e6d1689p-1, 0x1.0200p-48,
293 0x1.cdf0b555dc412p-1, 0x1.3600p-48,
294 0x1.cf3155b5bab3bp-1, -0x1.6900p-47,
295 0x1.d072d4a0789bcp-1, 0x1.9a00p-47,
296 0x1.d1b532b08c8fap-1, -0x1.5e00p-46,
297 0x1.d2f87080d8a85p-1, 0x1.d280p-46,
298 0x1.d43c8eacaa203p-1, 0x1.1a00p-47,
299 0x1.d5818dcfba491p-1, 0x1.f000p-50,
300 0x1.d6c76e862e6a1p-1, -0x1.3a00p-47,
301 0x1.d80e316c9834ep-1, -0x1.cd80p-47,
302 0x1.d955d71ff6090p-1, 0x1.4c00p-48,
303 0x1.da9e603db32aep-1, 0x1.f900p-48,
304 0x1.dbe7cd63a8325p-1, 0x1.9800p-49,
305 0x1.dd321f301b445p-1, -0x1.5200p-48,
306 0x1.de7d5641c05bfp-1, -0x1.d700p-46,
307 0x1.dfc97337b9aecp-1, -0x1.6140p-46,
308 0x1.e11676b197d5ep-1, 0x1.b480p-47,
309 0x1.e264614f5a3e7p-1, 0x1.0ce0p-43,
310 0x1.e3b333b16ee5cp-1, 0x1.c680p-47,
311 0x1.e502ee78b3fb4p-1, -0x1.9300p-47,
312 0x1.e653924676d68p-1, -0x1.5000p-49,
313 0x1.e7a51fbc74c44p-1, -0x1.7f80p-47,
314 0x1.e8f7977cdb726p-1, -0x1.3700p-48,
315 0x1.ea4afa2a490e8p-1, 0x1.5d00p-49,
316 0x1.eb9f4867ccae4p-1, 0x1.61a0p-46,
317 0x1.ecf482d8e680dp-1, 0x1.5500p-48,
318 0x1.ee4aaa2188514p-1, 0x1.6400p-51,
319 0x1.efa1bee615a13p-1, -0x1.e800p-49,
320 0x1.f0f9c1cb64106p-1, -0x1.a880p-48,
321 0x1.f252b376bb963p-1, -0x1.c900p-45,
322 0x1.f3ac948dd7275p-1, 0x1.a000p-53,
323 0x1.f50765b6e4524p-1, -0x1.4f00p-48,
324 0x1.f6632798844fdp-1, 0x1.a800p-51,
325 0x1.f7bfdad9cbe38p-1, 0x1.abc0p-48,
326 0x1.f91d802243c82p-1, -0x1.4600p-50,
327 0x1.fa7c1819e908ep-1, -0x1.b0c0p-47,
328 0x1.fbdba3692d511p-1, -0x1.0e00p-51,
329 0x1.fd3c22b8f7194p-1, -0x1.0de8p-46,
330 0x1.fe9d96b2a23eep-1, 0x1.e430p-49,
331 0x1.0000000000000p+0, 0x0.0000p+0,
332 0x1.00b1afa5abcbep+0, -0x1.3400p-52,
333 0x1.0163da9fb3303p+0, -0x1.2170p-46,
334 0x1.02168143b0282p+0, 0x1.a400p-52,
335 0x1.02c9a3e77806cp+0, 0x1.f980p-49,
336 0x1.037d42e11bbcap+0, -0x1.7400p-51,
337 0x1.04315e86e7f89p+0, 0x1.8300p-50,
338 0x1.04e5f72f65467p+0, -0x1.a3f0p-46,
339 0x1.059b0d315855ap+0, -0x1.2840p-47,
340 0x1.0650a0e3c1f95p+0, 0x1.1600p-48,
341 0x1.0706b29ddf71ap+0, 0x1.5240p-46,
342 0x1.07bd42b72a82dp+0, -0x1.9a00p-49,
343 0x1.0874518759bd0p+0, 0x1.6400p-49,
344 0x1.092bdf66607c8p+0, -0x1.0780p-47,
345 0x1.09e3ecac6f383p+0, -0x1.8000p-54,
346 0x1.0a9c79b1f3930p+0, 0x1.fa00p-48,
347 0x1.0b5586cf988fcp+0, -0x1.ac80p-48,
348 0x1.0c0f145e46c8ap+0, 0x1.9c00p-50,
349 0x1.0cc922b724816p+0, 0x1.5200p-47,
350 0x1.0d83b23395dd8p+0, -0x1.ad00p-48,
351 0x1.0e3ec32d3d1f3p+0, 0x1.bac0p-46,
352 0x1.0efa55fdfa9a6p+0, -0x1.4e80p-47,
353 0x1.0fb66affed2f0p+0, -0x1.d300p-47,
354 0x1.1073028d7234bp+0, 0x1.1500p-48,
355 0x1.11301d0125b5bp+0, 0x1.c000p-49,
356 0x1.11edbab5e2af9p+0, 0x1.6bc0p-46,
357 0x1.12abdc06c31d5p+0, 0x1.8400p-49,
358 0x1.136a814f2047dp+0, -0x1.ed00p-47,
359 0x1.1429aaea92de9p+0, 0x1.8e00p-49,
360 0x1.14e95934f3138p+0, 0x1.b400p-49,
361 0x1.15a98c8a58e71p+0, 0x1.5300p-47,
362 0x1.166a45471c3dfp+0, 0x1.3380p-47,
363 0x1.172b83c7d5211p+0, 0x1.8d40p-45,
364 0x1.17ed48695bb9fp+0, -0x1.5d00p-47,
365 0x1.18af9388c8d93p+0, -0x1.c880p-46,
366 0x1.1972658375d66p+0, 0x1.1f00p-46,
367 0x1.1a35beb6fcba7p+0, 0x1.0480p-46,
368 0x1.1af99f81387e3p+0, -0x1.7390p-43,
369 0x1.1bbe084045d54p+0, 0x1.4e40p-45,
370 0x1.1c82f95281c43p+0, -0x1.a200p-47,
371 0x1.1d4873168b9b2p+0, 0x1.3800p-49,
372 0x1.1e0e75eb44031p+0, 0x1.ac00p-49,
373 0x1.1ed5022fcd938p+0, 0x1.1900p-47,
374 0x1.1f9c18438cdf7p+0, -0x1.b780p-46,
375 0x1.2063b88628d8fp+0, 0x1.d940p-45,
376 0x1.212be3578a81ep+0, 0x1.8000p-50,
377 0x1.21f49917ddd41p+0, 0x1.b340p-45,
378 0x1.22bdda2791323p+0, 0x1.9f80p-46,
379 0x1.2387a6e7561e7p+0, -0x1.9c80p-46,
380 0x1.2451ffb821427p+0, 0x1.2300p-47,
381 0x1.251ce4fb2a602p+0, -0x1.3480p-46,
382 0x1.25e85711eceb0p+0, 0x1.2700p-46,
383 0x1.26b4565e27d16p+0, 0x1.1d00p-46,
384 0x1.2780e341de00fp+0, 0x1.1ee0p-44,
385 0x1.284dfe1f5633ep+0, -0x1.4c00p-46,
386 0x1.291ba7591bb30p+0, -0x1.3d80p-46,
387 0x1.29e9df51fdf09p+0, 0x1.8b00p-47,
388 0x1.2ab8a66d10e9bp+0, -0x1.27c0p-45,
389 0x1.2b87fd0dada3ap+0, 0x1.a340p-45,
390 0x1.2c57e39771af9p+0, -0x1.0800p-46,
391 0x1.2d285a6e402d9p+0, -0x1.ed00p-47,
392 0x1.2df961f641579p+0, -0x1.4200p-48,
393 0x1.2ecafa93e2ecfp+0, -0x1.4980p-45,
394 0x1.2f9d24abd8822p+0, -0x1.6300p-46,
395 0x1.306fe0a31b625p+0, -0x1.2360p-44,
396 0x1.31432edeea50bp+0, -0x1.0df8p-40,
397 0x1.32170fc4cd7b8p+0, -0x1.2480p-45,
398 0x1.32eb83ba8e9a2p+0, -0x1.5980p-45,
399 0x1.33c08b2641766p+0, 0x1.ed00p-46,
400 0x1.3496266e3fa27p+0, -0x1.c000p-50,
401 0x1.356c55f929f0fp+0, -0x1.0d80p-44,
402 0x1.36431a2de88b9p+0, 0x1.2c80p-45,
403 0x1.371a7373aaa39p+0, 0x1.0600p-45,
404 0x1.37f26231e74fep+0, -0x1.6600p-46,
405 0x1.38cae6d05d838p+0, -0x1.ae00p-47,
406 0x1.39a401b713ec3p+0, -0x1.4720p-43,
407 0x1.3a7db34e5a020p+0, 0x1.8200p-47,
408 0x1.3b57fbfec6e95p+0, 0x1.e800p-44,
409 0x1.3c32dc313a8f2p+0, 0x1.f800p-49,
410 0x1.3d0e544ede122p+0, -0x1.7a00p-46,
411 0x1.3dea64c1234bbp+0, 0x1.6300p-45,
412 0x1.3ec70df1c4eccp+0, -0x1.8a60p-43,
413 0x1.3fa4504ac7e8cp+0, -0x1.cdc0p-44,
414 0x1.40822c367a0bbp+0, 0x1.5b80p-45,
415 0x1.4160a21f72e95p+0, 0x1.ec00p-46,
416 0x1.423fb27094646p+0, -0x1.3600p-46,
417 0x1.431f5d950a920p+0, 0x1.3980p-45,
418 0x1.43ffa3f84b9ebp+0, 0x1.a000p-48,
419 0x1.44e0860618919p+0, -0x1.6c00p-48,
420 0x1.45c2042a7d201p+0, -0x1.bc00p-47,
421 0x1.46a41ed1d0016p+0, -0x1.2800p-46,
422 0x1.4786d668b3326p+0, 0x1.0e00p-44,
423 0x1.486a2b5c13c00p+0, -0x1.d400p-45,
424 0x1.494e1e192af04p+0, 0x1.c200p-47,
425 0x1.4a32af0d7d372p+0, -0x1.e500p-46,
426 0x1.4b17dea6db801p+0, 0x1.7800p-47,
427 0x1.4bfdad53629e1p+0, -0x1.3800p-46,
428 0x1.4ce41b817c132p+0, 0x1.0800p-47,
429 0x1.4dcb299fddddbp+0, 0x1.c700p-45,
430 0x1.4eb2d81d8ab96p+0, -0x1.ce00p-46,
431 0x1.4f9b2769d2d02p+0, 0x1.9200p-46,
432 0x1.508417f4531c1p+0, -0x1.8c00p-47,
433 0x1.516daa2cf662ap+0, -0x1.a000p-48,
434 0x1.5257de83f51eap+0, 0x1.a080p-43,
435 0x1.5342b569d4edap+0, -0x1.6d80p-45,
436 0x1.542e2f4f6ac1ap+0, -0x1.2440p-44,
437 0x1.551a4ca5d94dbp+0, 0x1.83c0p-43,
438 0x1.56070dde9116bp+0, 0x1.4b00p-45,
439 0x1.56f4736b529dep+0, 0x1.15a0p-43,
440 0x1.57e27dbe2c40ep+0, -0x1.9e00p-45,
441 0x1.58d12d497c76fp+0, -0x1.3080p-45,
442 0x1.59c0827ff0b4cp+0, 0x1.dec0p-43,
443 0x1.5ab07dd485427p+0, -0x1.4000p-51,
444 0x1.5ba11fba87af4p+0, 0x1.0080p-44,
445 0x1.5c9268a59460bp+0, -0x1.6c80p-45,
446 0x1.5d84590998e3fp+0, 0x1.69a0p-43,
447 0x1.5e76f15ad20e1p+0, -0x1.b400p-46,
448 0x1.5f6a320dcebcap+0, 0x1.7700p-46,
449 0x1.605e1b976dcb8p+0, 0x1.6f80p-45,
450 0x1.6152ae6cdf715p+0, 0x1.1000p-47,
451 0x1.6247eb03a5531p+0, -0x1.5d00p-46,
452 0x1.633dd1d1929b5p+0, -0x1.2d00p-46,
453 0x1.6434634ccc313p+0, -0x1.a800p-49,
454 0x1.652b9febc8efap+0, -0x1.8600p-45,
455 0x1.6623882553397p+0, 0x1.1fe0p-40,
456 0x1.671c1c708328ep+0, -0x1.7200p-44,
457 0x1.68155d44ca97ep+0, 0x1.6800p-49,
458 0x1.690f4b19e9471p+0, -0x1.9780p-45,
459};
460
461test "exp2f() special" {
462 try expectEqual(exp2f(0.0), 1.0);
463 try expectEqual(exp2f(-0.0), 1.0);
464 try expectEqual(exp2f(1.0), 2.0);
465 try expectEqual(exp2f(-1.0), 0.5);
466 try expectEqual(exp2f(math.inf(f32)), math.inf(f32));
467 try expect(math.isPositiveZero(exp2f(-math.inf(f32))));
468 try expect(math.isNan(exp2f(math.nan(f32))));
469 try expect(math.isNan(exp2f(math.snan(f32))));
470}
471
472test "exp2f() sanity" {
473 try expectEqual(exp2f(-0x1.0223a0p+3), 0x1.e8d134p-9);
474 try expectEqual(exp2f(0x1.161868p+2), 0x1.453672p+4);
475 try expectEqual(exp2f(-0x1.0c34b4p+3), 0x1.890ca0p-9);
476 try expectEqual(exp2f(-0x1.a206f0p+2), 0x1.622d4ep-7);
477 try expectEqual(exp2f(0x1.288bbcp+3), 0x1.340ecep+9);
478 try expectEqual(exp2f(0x1.52efd0p-1), 0x1.950eeep+0);
479 try expectEqual(exp2f(-0x1.a05cc8p-2), 0x1.824056p-1);
480 try expectEqual(exp2f(0x1.1f9efap-1), 0x1.79dfa2p+0);
481 try expectEqual(exp2f(0x1.8c5db0p-1), 0x1.b5ceacp+0);
482 try expectEqual(exp2f(-0x1.5b86eap-1), 0x1.3fd8bap-1);
483}
484
485test "exp2f() boundary" {
486 try expectEqual(exp2f(0x1.fffffep+6), 0x1.ffff4ep+127); // The last value before the result gets infinite
487 try expectEqual(exp2f(0x1p+7), math.inf(f32)); // The first value that gives infinite result
488 try expectEqual(exp2f(-0x1.2bccccp+7), 0x1p-149); // The last value before the result flushes to zero
489 try expectEqual(exp2f(-0x1.2cp+7), 0); // The first value at which the result flushes to zero
490 try expectEqual(exp2f(-0x1.f8p+6), 0x1p-126); // The last value before the result flushes to subnormal
491 try expectEqual(exp2f(-0x1.f80002p+6), 0x1.ffff50p-127); // The first value for which the result flushes to subnormal
492 try expectEqual(exp2f(0x1.fffffep+127), math.inf(f32)); // Max input value
493 try expectEqual(exp2f(0x1p-149), 1); // Min positive input value
494 try expectEqual(exp2f(-0x1p-149), 1); // Min negative input value
495 try expectEqual(exp2f(0x1p-126), 1); // First positive subnormal input
496 try expectEqual(exp2f(-0x1p-126), 1); // First negative subnormal input
497}
498
499test "exp2() special" {
500 try expectEqual(exp2(0.0), 1.0);
501 try expectEqual(exp2(-0.0), 1.0);
502 try expectEqual(exp2(1.0), 2.0);
503 try expectEqual(exp2(-1.0), 0.5);
504 try expectEqual(exp2(math.inf(f64)), math.inf(f64));
505 try expect(math.isPositiveZero(exp2(-math.inf(f64))));
506 try expect(math.isNan(exp2(math.nan(f64))));
507 try expect(math.isNan(exp2(math.snan(f64))));
508}
509
510test "exp2() sanity" {
511 try expectEqual(exp2(-0x1.02239f3c6a8f1p+3), 0x1.e8d13c396f452p-9);
512 try expectEqual(exp2(0x1.161868e18bc67p+2), 0x1.4536746bb6f12p+4);
513 try expectEqual(exp2(-0x1.0c34b3e01e6e7p+3), 0x1.890ca0c00b9a2p-9);
514 try expectEqual(exp2(-0x1.a206f0a19dcc4p+2), 0x1.622d4b0ebc6c1p-7);
515 try expectEqual(exp2(0x1.288bbb0d6a1e6p+3), 0x1.340ec7f3e607ep+9);
516 try expectEqual(exp2(0x1.52efd0cd80497p-1), 0x1.950eef4bc5451p+0);
517 try expectEqual(exp2(-0x1.a05cc754481d1p-2), 0x1.824056efc687cp-1);
518 try expectEqual(exp2(0x1.1f9ef934745cbp-1), 0x1.79dfa14ab121ep+0);
519 try expectEqual(exp2(0x1.8c5db097f7442p-1), 0x1.b5cead2247372p+0);
520 try expectEqual(exp2(-0x1.5b86ea8118a0ep-1), 0x1.3fd8ba33216b9p-1);
521}
522
523test "exp2() boundary" {
524 try expectEqual(exp2(0x1.fffffffffffffp+9), 0x1.ffffffffffd3ap+1023); // The last value before the result gets infinite
525 try expectEqual(exp2(0x1p+10), math.inf(f64)); // The first value that gives infinite result
526 try expectEqual(exp2(-0x1.0cbffffffffffp+10), 0x1p-1074); // The last value before the result flushes to zero
527 try expectEqual(exp2(-0x1.0ccp+10), 0); // The first value at which the result flushes to zero
528 try expectEqual(exp2(-0x1.ffp+9), 0x1p-1022); // The last value before the result flushes to subnormal
529 try expectEqual(exp2(-0x1.ff00000000001p+9), 0x1.ffffffffffd3ap-1023); // The first value for which the result flushes to subnormal
530 try expectEqual(exp2(0x1.fffffffffffffp+1023), math.inf(f64)); // Max input value
531 try expectEqual(exp2(0x1p-1074), 1); // Min positive input value
532 try expectEqual(exp2(-0x1p-1074), 1); // Min negative input value
533 try expectEqual(exp2(0x1p-1022), 1); // First positive subnormal input
534 try expectEqual(exp2(-0x1p-1022), 1); // First negative subnormal input
535}