diff options
| -rw-r--r-- | ChangeLog | 6 | ||||
| -rw-r--r-- | NEWS | 2 | ||||
| -rw-r--r-- | sysdeps/powerpc/fpu/e_sqrtf.c | 24 |
3 files changed, 20 insertions, 12 deletions
@@ -1,3 +1,9 @@ +2015-02-13 Joseph Myers <joseph@codesourcery.com> + + [BZ #17967] + * sysdeps/powerpc/fpu/e_sqrtf.c (__slow_ieee754_sqrtf): Use + __builtin_fmaf instead of relying on contraction of a * b + c. + 2015-02-12 J William Piggott <elseifthen@gmx.com> [BZ #17969] @@ -10,7 +10,7 @@ Version 2.22 * The following bugs are resolved with this release: 4719, 15467, 15790, 16560, 17912, 17932, 17944, 17949, 17964, 17965, - 17969. + 17967, 17969. Version 2.21 diff --git a/sysdeps/powerpc/fpu/e_sqrtf.c b/sysdeps/powerpc/fpu/e_sqrtf.c index 034b6f58ca..a684cf977a 100644 --- a/sysdeps/powerpc/fpu/e_sqrtf.c +++ b/sysdeps/powerpc/fpu/e_sqrtf.c @@ -87,26 +87,28 @@ __slow_ieee754_sqrtf (float x) /* Here we have three Newton-Raphson iterations each of a division and a square root and the remainder of the argument reduction, all interleaved. */ - sd = -(sg * sg - sx); + sd = -__builtin_fmaf (sg, sg, -sx); fsgi = (xi + 0x40000000) >> 1 & 0x7f800000; sy2 = sy + sy; - sg = sy * sd + sg; /* 16-bit approximation to sqrt(sx). */ - e = -(sy * sg - almost_half); + sg = __builtin_fmaf (sy, sd, sg); /* 16-bit approximation to + sqrt(sx). */ + e = -__builtin_fmaf (sy, sg, -almost_half); SET_FLOAT_WORD (fsg, fsgi); - sd = -(sg * sg - sx); - sy = sy + e * sy2; + sd = -__builtin_fmaf (sg, sg, -sx); + sy = __builtin_fmaf (e, sy2, sy); if ((xi & 0x7f800000) == 0) goto denorm; shx = sx * fsg; - sg = sg + sy * sd; /* 32-bit approximation to sqrt(sx), - but perhaps rounded incorrectly. */ + sg = __builtin_fmaf (sy, sd, sg); /* 32-bit approximation to + sqrt(sx), but perhaps + rounded incorrectly. */ sy2 = sy + sy; g = sg * fsg; - e = -(sy * sg - almost_half); - d = -(g * sg - shx); - sy = sy + e * sy2; + e = -__builtin_fmaf (sy, sg, -almost_half); + d = -__builtin_fmaf (g, sg, -shx); + sy = __builtin_fmaf (e, sy2, sy); fesetenv_register (fe); - return g + sy * d; + return __builtin_fmaf (sy, d, g); denorm: /* For denormalised numbers, we normalise, calculate the square root, and return an adjusted result. */ |