Module: wine Branch: master Commit: 7bb574eafd3a3ca61ced2f22e69a96b6bf848193 URL: https://source.winehq.org/git/wine.git/?a=commit;h=7bb574eafd3a3ca61ced2f22e...
Author: Piotr Caban piotr@codeweavers.com Date: Thu Jun 10 19:04:44 2021 +0200
msvcrt: Import powf implementation from musl.
Signed-off-by: Piotr Caban piotr@codeweavers.com Signed-off-by: Alexandre Julliard julliard@winehq.org
---
dlls/msvcrt/math.c | 177 ++++++++++++++++++++++++++++++++++++++++++++++++-- dlls/msvcrt/unixlib.c | 9 --- dlls/msvcrt/unixlib.h | 1 - 3 files changed, 171 insertions(+), 16 deletions(-)
diff --git a/dlls/msvcrt/math.c b/dlls/msvcrt/math.c index eaaeb9bec12..04597744548 100644 --- a/dlls/msvcrt/math.c +++ b/dlls/msvcrt/math.c @@ -1424,17 +1424,182 @@ float CDECL log10f( float x ) return dk * log10_2lo + (lo + hi) * ivln10lo + lo * ivln10hi + hi * ivln10hi + dk * log10_2hi; }
+/* Subnormal input is normalized so ix has negative biased exponent. + Output is multiplied by POWF_SCALE (where 1 << 5). */ +static double powf_log2(UINT32 ix) +{ + static const struct { + double invc, logc; + } T[] = { + { 0x1.661ec79f8f3bep+0, -0x1.efec65b963019p-2 * (1 << 5) }, + { 0x1.571ed4aaf883dp+0, -0x1.b0b6832d4fca4p-2 * (1 << 5) }, + { 0x1.49539f0f010bp+0, -0x1.7418b0a1fb77bp-2 * (1 << 5) }, + { 0x1.3c995b0b80385p+0, -0x1.39de91a6dcf7bp-2 * (1 << 5) }, + { 0x1.30d190c8864a5p+0, -0x1.01d9bf3f2b631p-2 * (1 << 5) }, + { 0x1.25e227b0b8eap+0, -0x1.97c1d1b3b7afp-3 * (1 << 5) }, + { 0x1.1bb4a4a1a343fp+0, -0x1.2f9e393af3c9fp-3 * (1 << 5) }, + { 0x1.12358f08ae5bap+0, -0x1.960cbbf788d5cp-4 * (1 << 5) }, + { 0x1.0953f419900a7p+0, -0x1.a6f9db6475fcep-5 * (1 << 5) }, + { 0x1p+0, 0x0p+0 * (1 << 4) }, + { 0x1.e608cfd9a47acp-1, 0x1.338ca9f24f53dp-4 * (1 << 5) }, + { 0x1.ca4b31f026aap-1, 0x1.476a9543891bap-3 * (1 << 5) }, + { 0x1.b2036576afce6p-1, 0x1.e840b4ac4e4d2p-3 * (1 << 5) }, + { 0x1.9c2d163a1aa2dp-1, 0x1.40645f0c6651cp-2 * (1 << 5) }, + { 0x1.886e6037841edp-1, 0x1.88e9c2c1b9ff8p-2 * (1 << 5) }, + { 0x1.767dcf5534862p-1, 0x1.ce0a44eb17bccp-2 * (1 << 5) } + }; + static const double A[] = { + 0x1.27616c9496e0bp-2 * (1 << 5), -0x1.71969a075c67ap-2 * (1 << 5), + 0x1.ec70a6ca7baddp-2 * (1 << 5), -0x1.7154748bef6c8p-1 * (1 << 5), + 0x1.71547652ab82bp0 * (1 << 5) + }; + + double z, r, r2, r4, p, q, y, y0, invc, logc; + UINT32 iz, top, tmp; + int k, i; + + /* x = 2^k z; where z is in range [OFF,2*OFF] and exact. + The range is split into N subintervals. + The ith subinterval contains z and c is near its center. */ + tmp = ix - 0x3f330000; + i = (tmp >> (23 - 4)) % (1 << 4); + top = tmp & 0xff800000; + iz = ix - top; + k = (INT32)top >> (23 - 5); /* arithmetic shift */ + invc = T[i].invc; + logc = T[i].logc; + z = *(float*)&iz; + + /* log2(x) = log1p(z/c-1)/ln2 + log2(c) + k */ + r = z * invc - 1; + y0 = logc + (double)k; + + /* Pipelined polynomial evaluation to approximate log1p(r)/ln2. */ + r2 = r * r; + y = A[0] * r + A[1]; + p = A[2] * r + A[3]; + r4 = r2 * r2; + q = A[4] * r + y0; + q = p * r2 + q; + y = y * r4 + q; + return y; +} + +/* The output of log2 and thus the input of exp2 is either scaled by N + (in case of fast toint intrinsics) or not. The unscaled xd must be + in [-1021,1023], sign_bias sets the sign of the result. */ +static float powf_exp2(double xd, UINT32 sign_bias) +{ + static const double C[] = { + 0x1.c6af84b912394p-5 / (1 << 5) / (1 << 5) / (1 << 5), + 0x1.ebfce50fac4f3p-3 / (1 << 5) / (1 << 5), + 0x1.62e42ff0c52d6p-1 / (1 << 5) + }; + + UINT64 ki, ski, t; + double kd, z, r, r2, y, s; + + /* N*x = k + r with r in [-1/2, 1/2] */ + kd = __round(xd); /* k */ + ki = kd; + r = xd - kd; + + /* exp2(x) = 2^(k/N) * 2^r ~= s * (C0*r^3 + C1*r^2 + C2*r + 1) */ + t = exp2f_T[ki % (1 << 5)]; + ski = ki + sign_bias; + t += ski << (52 - 5); + s = *(double*)&t; + z = C[0] * r + C[1]; + r2 = r * r; + y = C[2] * r + 1; + y = z * r2 + y; + y = y * s; + return y; +} + +/* Returns 0 if not int, 1 if odd int, 2 if even int. The argument is + the bit representation of a non-zero finite floating-point value. */ +static int powf_checkint(UINT32 iy) +{ + int e = iy >> 23 & 0xff; + if (e < 0x7f) + return 0; + if (e > 0x7f + 23) + return 2; + if (iy & ((1 << (0x7f + 23 - e)) - 1)) + return 0; + if (iy & (1 << (0x7f + 23 - e))) + return 1; + return 2; +} + /********************************************************************* * powf (MSVCRT.@) + * + * Copied from musl: src/math/powf.c src/math/powf_data.c */ float CDECL powf( float x, float y ) { - float z = unix_funcs->powf(x,y); - if (x < 0 && y != floorf(y)) return math_error(_DOMAIN, "powf", x, y, z); - if (!x && isfinite(y) && y < 0) return math_error(_SING, "powf", x, y, z); - if (isfinite(x) && isfinite(y) && !isfinite(z)) return math_error(_OVERFLOW, "powf", x, y, z); - if (x && isfinite(x) && isfinite(y) && !z) return math_error(_UNDERFLOW, "powf", x, y, z); - return z; + UINT32 sign_bias = 0; + UINT32 ix, iy; + double logx, ylogx; + + ix = *(UINT32*)&x; + iy = *(UINT32*)&y; + if (ix - 0x00800000 >= 0x7f800000 - 0x00800000 || + 2 * iy - 1 >= 2u * 0x7f800000 - 1) { + /* Either (x < 0x1p-126 or inf or nan) or (y is 0 or inf or nan). */ + if (2 * iy - 1 >= 2u * 0x7f800000 - 1) { + if (2 * iy == 0) + return 1.0f; + if (ix == 0x3f800000) + return 1.0f; + if (2 * ix > 2u * 0x7f800000 || 2 * iy > 2u * 0x7f800000) + return x + y; + if (2 * ix == 2 * 0x3f800000) + return 1.0f; + if ((2 * ix < 2 * 0x3f800000) == !(iy & 0x80000000)) + return 0.0f; /* |x|<1 && y==inf or |x|>1 && y==-inf. */ + return y * y; + } + if (2 * ix - 1 >= 2u * 0x7f800000 - 1) { + float x2 = x * x; + if (ix & 0x80000000 && powf_checkint(iy) == 1) + x2 = -x2; + if (iy & 0x80000000 && x2 == 0.0) + return math_error(_SING, "powf", x, 0, 1 / x2); + /* Without the barrier some versions of clang hoist the 1/x2 and + thus division by zero exception can be signaled spuriously. */ + return iy & 0x80000000 ? fp_barrierf(1 / x2) : x2; + } + /* x and y are non-zero finite. */ + if (ix & 0x80000000) { + /* Finite x < 0. */ + int yint = powf_checkint(iy); + if (yint == 0) + return math_error(_DOMAIN, "powf", x, 0, 0 / (x - x)); + if (yint == 1) + sign_bias = 1 << (5 + 11); + ix &= 0x7fffffff; + } + if (ix < 0x00800000) { + /* Normalize subnormal x so exponent becomes negative. */ + x *= 0x1p23f; + ix = *(UINT32*)&x; + ix &= 0x7fffffff; + ix -= 23 << 23; + } + } + logx = powf_log2(ix); + ylogx = y * logx; /* cannot overflow, y is single prec. */ + if ((*(UINT64*)&ylogx >> 47 & 0xffff) >= 0x40af800000000000llu >> 47) { + /* |y*log(x)| >= 126. */ + if (ylogx > 0x1.fffffffd1d571p+6 * (1 << 5)) + return math_error(_OVERFLOW, "powf", x, 0, (sign_bias ? -1.0 : 1.0) * 0x1p1023); + if (ylogx <= -150.0 * (1 << 5)) + return math_error(_UNDERFLOW, "powf", x, 0, (sign_bias ? -1.0 : 1.0) / 0x1p1023); + } + return powf_exp2(ylogx, sign_bias); }
/********************************************************************* diff --git a/dlls/msvcrt/unixlib.c b/dlls/msvcrt/unixlib.c index 0498a736812..2b189246084 100644 --- a/dlls/msvcrt/unixlib.c +++ b/dlls/msvcrt/unixlib.c @@ -70,20 +70,11 @@ static double CDECL unix_pow( double x, double y ) return pow( x, y ); }
-/********************************************************************* - * powf - */ -static float CDECL unix_powf( float x, float y ) -{ - return powf( x, y ); -} - static const struct unix_funcs funcs = { unix_exp, unix_exp2, unix_pow, - unix_powf, };
NTSTATUS CDECL __wine_init_unix_lib( HMODULE module, DWORD reason, const void *ptr_in, void *ptr_out ) diff --git a/dlls/msvcrt/unixlib.h b/dlls/msvcrt/unixlib.h index 21bb5e6c130..e82977e4097 100644 --- a/dlls/msvcrt/unixlib.h +++ b/dlls/msvcrt/unixlib.h @@ -26,7 +26,6 @@ struct unix_funcs double (CDECL *exp)(double x); double (CDECL *exp2)(double x); double (CDECL *pow)(double x, double y); - float (CDECL *powf)(float x, float y); };
#endif /* __UNIXLIB_H */