zig

commit 4aadb5e4a5e09d6b2018fecb364c0fabec028c9a (tree)
parent 0aae9768aab8e1b534eb9a7682ad36ab4ef0487d
Author: Jeff Anderson <kj4tmp@gmail.com>
Date:   Sat, 31 Jan 2026 22:55:11 -0800

libzigc: cbrtf

Diffstat:
M
lib/c/math.zig
 | 
5
+++++
D
lib/libc/musl/src/math/cbrtf.c
 | 
66
------------------------------------------------------------------
M
src/libs/musl.zig
 | 
1
-
M
src/libs/wasi_libc.zig
 | 
1
-

4 files changed, 5 insertions(+), 68 deletions(-)
diff --git a/lib/c/math.zig b/lib/c/math.zig
@@ -40,6 +40,7 @@ comptime {
         @export(&atan, .{ .name = "atan", .linkage = common.linkage, .visibility = common.visibility });
         @export(&atanl, .{ .name = "atanl", .linkage = common.linkage, .visibility = common.visibility });
         @export(&cbrt, .{ .name = "cbrt", .linkage = common.linkage, .visibility = common.visibility });
+        @export(&cbrtf, .{ .name = "cbrtf", .linkage = common.linkage, .visibility = common.visibility });
     }
 
     if (builtin.target.isMuslLibC()) {
@@ -111,3 +112,7 @@ fn copysignl(x: c_longdouble, y: c_longdouble) callconv(.c) c_longdouble {
 fn cbrt(x: f64) callconv(.c) f64 {
     return math.cbrt(x);
 }
+
+fn cbrtf(x: f32) callconv(.c) f32 {
+    return math.cbrt(x);
+}
diff --git a/lib/libc/musl/src/math/cbrtf.c b/lib/libc/musl/src/math/cbrtf.c
@@ -1,66 +0,0 @@
-/* origin: FreeBSD /usr/src/lib/msun/src/s_cbrtf.c */
-/*
- * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
- * Debugged and optimized by Bruce D. Evans.
- */
-/*
- * ====================================================
- * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
- *
- * Developed at SunPro, a Sun Microsystems, Inc. business.
- * Permission to use, copy, modify, and distribute this
- * software is freely granted, provided that this notice
- * is preserved.
- * ====================================================
- */
-/* cbrtf(x)
- * Return cube root of x
- */
-
-#include <math.h>
-#include <stdint.h>
-
-static const unsigned
-B1 = 709958130, /* B1 = (127-127.0/3-0.03306235651)*2**23 */
-B2 = 642849266; /* B2 = (127-127.0/3-24/3-0.03306235651)*2**23 */
-
-float cbrtf(float x)
-{
-	double_t r,T;
-	union {float f; uint32_t i;} u = {x};
-	uint32_t hx = u.i & 0x7fffffff;
-
-	if (hx >= 0x7f800000)  /* cbrt(NaN,INF) is itself */
-		return x + x;
-
-	/* rough cbrt to 5 bits */
-	if (hx < 0x00800000) {  /* zero or subnormal? */
-		if (hx == 0)
-			return x;  /* cbrt(+-0) is itself */
-		u.f = x*0x1p24f;
-		hx = u.i & 0x7fffffff;
-		hx = hx/3 + B2;
-	} else
-		hx = hx/3 + B1;
-	u.i &= 0x80000000;
-	u.i |= hx;
-
-	/*
-	 * First step Newton iteration (solving t*t-x/t == 0) to 16 bits.  In
-	 * double precision so that its terms can be arranged for efficiency
-	 * without causing overflow or underflow.
-	 */
-	T = u.f;
-	r = T*T*T;
-	T = T*((double_t)x+x+r)/(x+r+r);
-
-	/*
-	 * Second step Newton iteration to 47 bits.  In double precision for
-	 * efficiency and accuracy.
-	 */
-	r = T*T*T;
-	T = T*((double_t)x+x+r)/(x+r+r);
-
-	/* rounding to 24 bits is perfect in round-to-nearest mode */
-	return T;
-}
diff --git a/src/libs/musl.zig b/src/libs/musl.zig
@@ -839,7 +839,6 @@ const src_files = [_][]const u8{
     "musl/src/math/atanh.c",
     "musl/src/math/atanhf.c",
     "musl/src/math/atanhl.c",
-    "musl/src/math/cbrtf.c",
     "musl/src/math/cbrtl.c",
     "musl/src/math/__cos.c",
     "musl/src/math/__cosdf.c",
diff --git a/src/libs/wasi_libc.zig b/src/libs/wasi_libc.zig
@@ -701,7 +701,6 @@ const libc_top_half_src_files = [_][]const u8{
     "musl/src/math/atanh.c",
     "musl/src/math/atanhf.c",
     "musl/src/math/atanhl.c",
-    "musl/src/math/cbrtf.c",
     "musl/src/math/cbrtl.c",
     "musl/src/math/__cos.c",
     "musl/src/math/__cosdf.c",