From 21fc85f035ef73d88d3b9864941a1670486af5ad Mon Sep 17 00:00:00 2001 From: Daggerfall-is-the-best-TES-game Date: Mon, 19 Jan 2026 22:43:57 +0100 Subject: [PATCH] Add acos to ziglibc (#30888) Since this is my first time contributing I wanted to keep it simple and I added just one function I tested with ```bash stage3/bin/zig build -p stage4 -Dno-lib -Dno-langref -Denable-llvm=true --search-prefix ~/repos/zig-boostrap/out/native-linux-musl-baseline/ stage4/bin/zig build test-libc -Dlibc-test-path=../libc-test -Dtest-target-filter=x86_64-linux-musl ``` and the tests passed. I'm planning on doing more once I get the hang of it. Co-authored-by: david Reviewed-on: https://codeberg.org/ziglang/zig/pulls/30888 Reviewed-by: Andrew Kelley Co-authored-by: Daggerfall-is-the-best-TES-game Co-committed-by: Daggerfall-is-the-best-TES-game --- lib/c/math.zig | 8 +++ lib/libc/musl/src/math/acos.c | 101 ---------------------------------- src/libs/musl.zig | 1 - src/libs/wasi_libc.zig | 1 - 4 files changed, 8 insertions(+), 103 deletions(-) delete mode 100644 lib/libc/musl/src/math/acos.c diff --git a/lib/c/math.zig b/lib/c/math.zig index 3e4aa662d09ccde4b42ccdb48dfc08e19edd0154..8a6c91be2efc735326a5a56d1fe3452f8837bb2b 100644 --- a/lib/c/math.zig +++ b/lib/c/math.zig @@ -33,6 +33,10 @@ comptime { @export(&nanl, .{ .name = "nanl", .linkage = common.linkage, .visibility = common.visibility }); } + if (builtin.target.isMuslLibC() or builtin.target.isWasiLibC()) { + @export(&acos, .{ .name = "acos", .linkage = common.linkage, .visibility = common.visibility }); + } + if (builtin.target.isMuslLibC()) { @export(©signf, .{ .name = "copysignf", .linkage = common.linkage, .visibility = common.visibility }); @export(©sign, .{ .name = "copysign", .linkage = common.linkage, .visibility = common.visibility }); @@ -40,6 +44,10 @@ comptime { @export(©signl, .{ .name = "copysignl", .linkage = common.linkage, .visibility = common.visibility }); } +fn acos(x: f64) callconv(.c) f64 { + return std.math.acos(x); +} + fn isnan(x: f64) callconv(.c) c_int { return if (std.math.isNan(x)) 1 else 0; } diff --git a/lib/libc/musl/src/math/acos.c b/lib/libc/musl/src/math/acos.c deleted file mode 100644 index ea9c87bf087809f9a6b1fa6a2ed2f065d8184f72..0000000000000000000000000000000000000000 --- a/lib/libc/musl/src/math/acos.c +++ /dev/null @@ -1,101 +0,0 @@ -/* origin: FreeBSD /usr/src/lib/msun/src/e_acos.c */ -/* - * ==================================================== - * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. - * - * Developed at SunSoft, a Sun Microsystems, Inc. business. - * Permission to use, copy, modify, and distribute this - * software is freely granted, provided that this notice - * is preserved. - * ==================================================== - */ -/* acos(x) - * Method : - * acos(x) = pi/2 - asin(x) - * acos(-x) = pi/2 + asin(x) - * For |x|<=0.5 - * acos(x) = pi/2 - (x + x*x^2*R(x^2)) (see asin.c) - * For x>0.5 - * acos(x) = pi/2 - (pi/2 - 2asin(sqrt((1-x)/2))) - * = 2asin(sqrt((1-x)/2)) - * = 2s + 2s*z*R(z) ...z=(1-x)/2, s=sqrt(z) - * = 2f + (2c + 2s*z*R(z)) - * where f=hi part of s, and c = (z-f*f)/(s+f) is the correction term - * for f so that f+c ~ sqrt(z). - * For x<-0.5 - * acos(x) = pi - 2asin(sqrt((1-|x|)/2)) - * = pi - 0.5*(s+s*z*R(z)), where z=(1-|x|)/2,s=sqrt(z) - * - * Special cases: - * if x is NaN, return x itself; - * if |x|>1, return NaN with invalid signal. - * - * Function needed: sqrt - */ - -#include "libm.h" - -static const double -pio2_hi = 1.57079632679489655800e+00, /* 0x3FF921FB, 0x54442D18 */ -pio2_lo = 6.12323399573676603587e-17, /* 0x3C91A626, 0x33145C07 */ -pS0 = 1.66666666666666657415e-01, /* 0x3FC55555, 0x55555555 */ -pS1 = -3.25565818622400915405e-01, /* 0xBFD4D612, 0x03EB6F7D */ -pS2 = 2.01212532134862925881e-01, /* 0x3FC9C155, 0x0E884455 */ -pS3 = -4.00555345006794114027e-02, /* 0xBFA48228, 0xB5688F3B */ -pS4 = 7.91534994289814532176e-04, /* 0x3F49EFE0, 0x7501B288 */ -pS5 = 3.47933107596021167570e-05, /* 0x3F023DE1, 0x0DFDF709 */ -qS1 = -2.40339491173441421878e+00, /* 0xC0033A27, 0x1C8A2D4B */ -qS2 = 2.02094576023350569471e+00, /* 0x40002AE5, 0x9C598AC8 */ -qS3 = -6.88283971605453293030e-01, /* 0xBFE6066C, 0x1B8D0159 */ -qS4 = 7.70381505559019352791e-02; /* 0x3FB3B8C5, 0xB12E9282 */ - -static double R(double z) -{ - double_t p, q; - p = z*(pS0+z*(pS1+z*(pS2+z*(pS3+z*(pS4+z*pS5))))); - q = 1.0+z*(qS1+z*(qS2+z*(qS3+z*qS4))); - return p/q; -} - -double acos(double x) -{ - double z,w,s,c,df; - uint32_t hx,ix; - - GET_HIGH_WORD(hx, x); - ix = hx & 0x7fffffff; - /* |x| >= 1 or nan */ - if (ix >= 0x3ff00000) { - uint32_t lx; - - GET_LOW_WORD(lx,x); - if ((ix-0x3ff00000 | lx) == 0) { - /* acos(1)=0, acos(-1)=pi */ - if (hx >> 31) - return 2*pio2_hi + 0x1p-120f; - return 0; - } - return 0/(x-x); - } - /* |x| < 0.5 */ - if (ix < 0x3fe00000) { - if (ix <= 0x3c600000) /* |x| < 2**-57 */ - return pio2_hi + 0x1p-120f; - return pio2_hi - (x - (pio2_lo-x*R(x*x))); - } - /* x < -0.5 */ - if (hx >> 31) { - z = (1.0+x)*0.5; - s = sqrt(z); - w = R(z)*s-pio2_lo; - return 2*(pio2_hi - (s+w)); - } - /* x > 0.5 */ - z = (1.0-x)*0.5; - s = sqrt(z); - df = s; - SET_LOW_WORD(df,0); - c = (z-df*df)/(s+df); - w = R(z)*s+c; - return 2*(df+w); -} diff --git a/src/libs/musl.zig b/src/libs/musl.zig index f537ef43567c2f0073c54acca0e972cd071d21d5..7313eee2c5f128d8d4cf23d68bac369446a348bd 100644 --- a/src/libs/musl.zig +++ b/src/libs/musl.zig @@ -824,7 +824,6 @@ const src_files = [_][]const u8{ "musl/src/math/aarch64/rintf.c", "musl/src/math/aarch64/round.c", "musl/src/math/aarch64/roundf.c", - "musl/src/math/acos.c", "musl/src/math/acosf.c", "musl/src/math/acosh.c", "musl/src/math/acoshf.c", diff --git a/src/libs/wasi_libc.zig b/src/libs/wasi_libc.zig index 1afe05167223a8c034ce4dd8790064f49266cd04..db222c115f25fcefa3efa7132bbb06e00ba00225 100644 --- a/src/libs/wasi_libc.zig +++ b/src/libs/wasi_libc.zig @@ -684,7 +684,6 @@ const libc_top_half_src_files = [_][]const u8{ "musl/src/locale/strtod_l.c", "musl/src/locale/wcscoll.c", "musl/src/locale/wcsxfrm.c", - "musl/src/math/acos.c", "musl/src/math/acosf.c", "musl/src/math/acosh.c", "musl/src/math/acoshf.c", -- 2.54.0