diff --git a/newlib/ChangeLog b/newlib/ChangeLog index ae9584373..ae96c236e 100644 --- a/newlib/ChangeLog +++ b/newlib/ChangeLog @@ -1,3 +1,9 @@ +2005-06-28 Dave Korn + + * libm/common/s_lrint.c (lrint): Fix signed-vs-unsigned comparison + and miscalculation caused by fp representation of zero. + * libm/common/sf_lrint.c (lrintf): Likewise. + 2005-06-16 Christopher Faylor * libc/stdio/vfprintf.c (cvt): Don't rely on pointer aliasing to diff --git a/newlib/libm/common/s_lrint.c b/newlib/libm/common/s_lrint.c index 541bf2c7e..45759f194 100644 --- a/newlib/libm/common/s_lrint.c +++ b/newlib/libm/common/s_lrint.c @@ -54,7 +54,11 @@ TWO52[2]={ long int result; EXTRACT_WORDS(i0,i1,x); + + /* Extract sign bit. */ sx = (i0>>31)&1; + + /* Extract exponent field. */ j0 = ((i0 & 0x7ff00000) >> 20) - 1023; if(j0 < 20) @@ -66,13 +70,17 @@ TWO52[2]={ w = TWO52[sx] + x; t = w - TWO52[sx]; GET_HIGH_WORD(i0, t); + /* Detect the all-zeros representation of plus and + minus zero, which fails the calculation below. */ + if ((i0 & ~(1 << 31)) == 0) + return 0; j0 = ((i0 & 0x7ff00000) >> 20) - 1023; i0 &= 0x000fffff; i0 |= 0x00100000; result = i0 >> (20 - j0); } } - else if (j0 < (8 * sizeof (long int)) - 1) + else if (j0 < (int)(8 * sizeof (long int)) - 1) { if (j0 >= 52) result = ((long int) i0 << (j0 - 20)) | (i1 << (j0 - 52)); diff --git a/newlib/libm/common/sf_lrint.c b/newlib/libm/common/sf_lrint.c index a58508f02..427bbb655 100644 --- a/newlib/libm/common/sf_lrint.c +++ b/newlib/libm/common/sf_lrint.c @@ -28,6 +28,10 @@ static const float #else static float #endif +/* Adding a float, x, to 2^23 will cause the result to be rounded based on + the fractional part of x, according to the implementation's current rounding + mode. 2^23 is the smallest float that can be represented using all 23 significant + digits. */ TWO23[2]={ 8.3886080000e+06, /* 0x4b000000 */ -8.3886080000e+06, /* 0xcb000000 */ @@ -54,7 +58,7 @@ TWO23[2]={ /* Extract exponent field. */ j0 = ((i0 & 0x7f800000) >> 23) - 127; - if (j0 < (sizeof (long int) * 8) - 1) + if (j0 < (int)(sizeof (long int) * 8) - 1) { if (j0 < -1) return 0; @@ -65,6 +69,10 @@ TWO23[2]={ w = TWO23[sx] + x; t = w - TWO23[sx]; GET_FLOAT_WORD (i0, t); + /* Detect the all-zeros representation of plus and + minus zero, which fails the calculation below. */ + if ((i0 & ~(1 << 31)) == 0) + return 0; j0 = ((i0 >> 23) & 0xff) - 0x7f; i0 &= 0x7fffff; i0 |= 0x800000;