| author |  mihael <hi@mihaelm.com> 2026-03-15 21:22:01+01:00 |
| committer | mihael <hi@mihaelm.com> 2026-03-17 23:33:10+01:00 |
| log | 4cad6f5372f6f17e249c24fba4d23466fa853fc0 |
| tree | 570937b9a319f0e31af630229fe507275379b590 |
| parent | 014178725744eda46db04ccfe44187ef616ceaf7 |
| signature |  Signed by SSH key SHA256:aoFoShdYLdrqMichqKXSSieTKUfACUIDJHsKc4V2tQg |
`libzigc`: Implement `modfl`
The changes were tested by running:
```
$ ./build/stage3/bin/zig build -p stage4 -Denable-llvm -Dno-lib
$ stage4/bin/zig build test-libc -Dlibc-test-path=<LIBC-TEST-PATH> -Dtest-filter=modfl -fqemu -fwasmtime --summary line
Build Summary: 369/369 steps succeeded
```6 files changed, 9 insertions(+), 99 deletions(-)
lib/c/math.zig+9-2
| ... | @@ -39,6 +39,7 @@ comptime { | ... | @@ -39,6 +39,7 @@ comptime { |
| 39 | symbol(&hypotf, "hypotf"); | 39 | symbol(&hypotf, "hypotf"); |
| 40 | symbol(&hypotl, "hypotl"); | 40 | symbol(&hypotl, "hypotl"); |
| 41 | symbol(&modff, "modff"); | 41 | symbol(&modff, "modff"); |
| 42 | symbol(&modfl, "modfl"); | ||
| 42 | symbol(&nan, "nan"); | 43 | symbol(&nan, "nan"); |
| 43 | symbol(&nanf, "nanf"); | 44 | symbol(&nanf, "nanf"); |
| 44 | symbol(&nanl, "nanl"); | 45 | symbol(&nanl, "nanl"); |
| ... | @@ -201,11 +202,16 @@ fn modff(x: f32, iptr: *f32) callconv(.c) f32 { | ... | @@ -201,11 +202,16 @@ fn modff(x: f32, iptr: *f32) callconv(.c) f32 { |
| 201 | return modfGeneric(f32, x, iptr); | 202 | return modfGeneric(f32, x, iptr); |
| 202 | } | 203 | } |
| 203 | 204 | ||
| 205 | fn modfl(x: c_longdouble, iptr: *c_longdouble) callconv(.c) c_longdouble { | ||
| 206 | return modfGeneric(c_longdouble, x, iptr); | ||
| 207 | } | ||
| 208 | |||
| 204 | fn testModf(comptime T: type) !void { | 209 | fn testModf(comptime T: type) !void { |
| 205 | // Choose the appropriate `modf` impl to test based on type | 210 | // Choose the appropriate `modf` impl to test based on type |
| 206 | const f = switch (T) { | 211 | const f = switch (T) { |
| 207 | f64 => modf, | ||
| 208 | f32 => modff, | 212 | f32 => modff, |
| 213 | f64 => modf, | ||
| 214 | c_longdouble => modfl, | ||
| 209 | else => @compileError("modf not implemented for " ++ @typeName(T)), | 215 | else => @compileError("modf not implemented for " ++ @typeName(T)), |
| 210 | }; | 216 | }; |
| 211 | 217 | ||
| ... | @@ -248,8 +254,9 @@ fn testModf(comptime T: type) !void { | ... | @@ -248,8 +254,9 @@ fn testModf(comptime T: type) !void { |
| 248 | } | 254 | } |
| 249 | 255 | ||
| 250 | test "modf" { | 256 | test "modf" { |
| 251 | try testModf(f64); | ||
| 252 | try testModf(f32); | 257 | try testModf(f32); |
| 258 | try testModf(f64); | ||
| 259 | try testModf(c_longdouble); | ||
| 253 | } | 260 | } |
| 254 | 261 | ||
| 255 | fn nan(_: [*:0]const c_char) callconv(.c) f64 { | 262 | fn nan(_: [*:0]const c_char) callconv(.c) f64 { |
lib/libc/mingw/math/modfl.c deleted-41
| ... | @@ -1,41 +0,0 @@ | ||
| 1 | /** | ||
| 2 | * This file has no copyright assigned and is placed in the Public Domain. | ||
| 3 | * This file is part of the mingw-w64 runtime package. | ||
| 4 | * No warranty is given; refer to the file DISCLAIMER.PD within this package. | ||
| 5 | */ | ||
| 6 | #include <fenv.h> | ||
| 7 | #include <math.h> | ||
| 8 | #include <errno.h> | ||
| 9 | |||
| 10 | long double | ||
| 11 | modfl (long double value, long double* iptr) | ||
| 12 | { | ||
| 13 | long double int_part = 0.0L; | ||
| 14 | /* truncate */ | ||
| 15 | #if (defined(_AMD64_) && !defined(_ARM64EC_)) || (defined(__x86_64__) && !defined(__arm64ec__)) | ||
| 16 | asm volatile ("subq $8, %%rsp\n" | ||
| 17 | "fnstcw 4(%%rsp)\n" | ||
| 18 | "movzwl 4(%%rsp), %%eax\n" | ||
| 19 | "orb $12, %%ah\n" | ||
| 20 | "movw %%ax, (%%rsp)\n" | ||
| 21 | "fldcw (%%rsp)\n" | ||
| 22 | "frndint\n" | ||
| 23 | "fldcw 4(%%rsp)\n" | ||
| 24 | "addq $8, %%rsp\n" : "=t" (int_part) : "0" (value) : "eax"); /* round */ | ||
| 25 | #elif defined(_X86_) || defined(__i386__) | ||
| 26 | asm volatile ("push %%eax\n\tsubl $8, %%esp\n" | ||
| 27 | "fnstcw 4(%%esp)\n" | ||
| 28 | "movzwl 4(%%esp), %%eax\n" | ||
| 29 | "orb $12, %%ah\n" | ||
| 30 | "movw %%ax, (%%esp)\n" | ||
| 31 | "fldcw (%%esp)\n" | ||
| 32 | "frndint\n" | ||
| 33 | "fldcw 4(%%esp)\n" | ||
| 34 | "addl $8, %%esp\n\tpop %%eax\n" : "=t" (int_part) : "0" (value) : "eax"); /* round */ | ||
| 35 | #else | ||
| 36 | int_part = truncl(value); | ||
| 37 | #endif | ||
| 38 | if (iptr) | ||
| 39 | *iptr = int_part; | ||
| 40 | return (isinf (value) ? 0.0L : value - int_part); | ||
| 41 | } | ||
lib/libc/musl/src/math/modfl.c deleted-53
| ... | @@ -1,53 +0,0 @@ | ||
| 1 | #include "libm.h" | ||
| 2 | |||
| 3 | #if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024 | ||
| 4 | long double modfl(long double x, long double *iptr) | ||
| 5 | { | ||
| 6 | double d; | ||
| 7 | long double r; | ||
| 8 | |||
| 9 | r = modf(x, &d); | ||
| 10 | *iptr = d; | ||
| 11 | return r; | ||
| 12 | } | ||
| 13 | #elif (LDBL_MANT_DIG == 64 || LDBL_MANT_DIG == 113) && LDBL_MAX_EXP == 16384 | ||
| 14 | |||
| 15 | static const long double toint = 1/LDBL_EPSILON; | ||
| 16 | |||
| 17 | long double modfl(long double x, long double *iptr) | ||
| 18 | { | ||
| 19 | union ldshape u = {x}; | ||
| 20 | int e = (u.i.se & 0x7fff) - 0x3fff; | ||
| 21 | int s = u.i.se >> 15; | ||
| 22 | long double absx; | ||
| 23 | long double y; | ||
| 24 | |||
| 25 | /* no fractional part */ | ||
| 26 | if (e >= LDBL_MANT_DIG-1) { | ||
| 27 | *iptr = x; | ||
| 28 | if (isnan(x)) | ||
| 29 | return x; | ||
| 30 | return s ? -0.0 : 0.0; | ||
| 31 | } | ||
| 32 | |||
| 33 | /* no integral part*/ | ||
| 34 | if (e < 0) { | ||
| 35 | *iptr = s ? -0.0 : 0.0; | ||
| 36 | return x; | ||
| 37 | } | ||
| 38 | |||
| 39 | /* raises spurious inexact */ | ||
| 40 | absx = s ? -x : x; | ||
| 41 | y = absx + toint - toint - absx; | ||
| 42 | if (y == 0) { | ||
| 43 | *iptr = x; | ||
| 44 | return s ? -0.0 : 0.0; | ||
| 45 | } | ||
| 46 | if (y > 0) | ||
| 47 | y -= 1; | ||
| 48 | if (s) | ||
| 49 | y = -y; | ||
| 50 | *iptr = x + y; | ||
| 51 | return -y; | ||
| 52 | } | ||
| 53 | #endif | ||
src/libs/mingw.zig-1
| ... | @@ -619,7 +619,6 @@ const mingw32_generic_src = [_][]const u8{ | ... | @@ -619,7 +619,6 @@ const mingw32_generic_src = [_][]const u8{ |
| 619 | "math" ++ path.sep_str ++ "lgamma.c", | 619 | "math" ++ path.sep_str ++ "lgamma.c", |
| 620 | "math" ++ path.sep_str ++ "lgammaf.c", | 620 | "math" ++ path.sep_str ++ "lgammaf.c", |
| 621 | "math" ++ path.sep_str ++ "lgammal.c", | 621 | "math" ++ path.sep_str ++ "lgammal.c", |
| 622 | "math" ++ path.sep_str ++ "modfl.c", | ||
| 623 | "math" ++ path.sep_str ++ "powi.c", | 622 | "math" ++ path.sep_str ++ "powi.c", |
| 624 | "math" ++ path.sep_str ++ "powif.c", | 623 | "math" ++ path.sep_str ++ "powif.c", |
| 625 | "math" ++ path.sep_str ++ "powil.c", | 624 | "math" ++ path.sep_str ++ "powil.c", |
src/libs/musl.zig-1
| ... | @@ -934,7 +934,6 @@ const src_files = [_][]const u8{ | ... | @@ -934,7 +934,6 @@ const src_files = [_][]const u8{ |
| 934 | "musl/src/math/__math_uflowf.c", | 934 | "musl/src/math/__math_uflowf.c", |
| 935 | "musl/src/math/__math_xflow.c", | 935 | "musl/src/math/__math_xflow.c", |
| 936 | "musl/src/math/__math_xflowf.c", | 936 | "musl/src/math/__math_xflowf.c", |
| 937 | "musl/src/math/modfl.c", | ||
| 938 | "musl/src/math/nearbyint.c", | 937 | "musl/src/math/nearbyint.c", |
| 939 | "musl/src/math/nearbyintf.c", | 938 | "musl/src/math/nearbyintf.c", |
| 940 | "musl/src/math/nearbyintl.c", | 939 | "musl/src/math/nearbyintl.c", |
src/libs/wasi_libc.zig-1
| ... | @@ -755,7 +755,6 @@ const libc_top_half_src_files = [_][]const u8{ | ... | @@ -755,7 +755,6 @@ const libc_top_half_src_files = [_][]const u8{ |
| 755 | "musl/src/math/__math_uflowf.c", | 755 | "musl/src/math/__math_uflowf.c", |
| 756 | "musl/src/math/__math_xflow.c", | 756 | "musl/src/math/__math_xflow.c", |
| 757 | "musl/src/math/__math_xflowf.c", | 757 | "musl/src/math/__math_xflowf.c", |
| 758 | "musl/src/math/modfl.c", | ||
| 759 | "musl/src/math/nearbyintl.c", | 758 | "musl/src/math/nearbyintl.c", |
| 760 | "musl/src/math/nextafter.c", | 759 | "musl/src/math/nextafter.c", |
| 761 | "musl/src/math/nextafterf.c", | 760 | "musl/src/math/nextafterf.c", |