Message ID | alpine.DEB.2.21.2007012203460.14918@digraph.polyomino.org.uk |
---|---|
State | New |
Headers | show |
Series | Use C2x return value from getpayload of non-NaN (bug 26073) | expand |
On 7/1/20 6:05 PM, Joseph Myers wrote: > In TS 18661-1, getpayload had an unspecified return value for a > non-NaN argument, while C2x requires the return value -1 in that case. Reviewed TS 18661-1 F.10.13.1 getpayload and confirmed the result is unspecified for non-NaN argument case. Confirmed in N2454 that if *x is not a NaN that the result shall be -1 (not unspecified as in TS 18661-1). > This patch implements the return value of -1. I don't think this is > worth having a new symbol version that's an alias of the old one, > although occasionally we do that in such cases where the new function > semantics are a refinement of the old ones (to avoid programs relying > on the new semantics running on older glibc versions but not behaving > as intended). > > Tested for x86_64 and x86; also ran math/ tests for aarch64 and > powerpc. OK for mater. Reviewed-by: Carlos O'Donell <carlos@redhat.com> > --- > > Carlos, is this OK at the current slush development stage? Yes it is. I consider this a "forward looking" change that while making a semantic change is within the scope of a bug fix. > diff --git a/manual/arith.texi b/manual/arith.texi > index 89c2c064f1..75eaf67fe7 100644 > --- a/manual/arith.texi > +++ b/manual/arith.texi > @@ -1895,9 +1895,10 @@ propagated from NaN inputs to the result of a floating-point > operation. These functions, defined by TS 18661-1:2014 and TS > 18661-3:2015, return the payload of the NaN pointed to by @var{x} > (returned as a positive integer, or positive zero, represented as a > -floating-point number); if @var{x} is not a NaN, they return an > -unspecified value. They raise no floating-point exceptions even for > -signaling NaNs. > +floating-point number); if @var{x} is not a NaN, they return > +@minus{}1. They raise no floating-point exceptions even for signaling > +NaNs. (The return value of @minus{}1 for an argument that is not a > +NaN is specified in C2x; the value was unspecified in TS 18661.) OK. > @end deftypefun > > @deftypefun int setpayload (double *@var{x}, double @var{payload}) > diff --git a/math/libm-test-getpayload.inc b/math/libm-test-getpayload.inc > index bd660471aa..72e3c19d1e 100644 > --- a/math/libm-test-getpayload.inc > +++ b/math/libm-test-getpayload.inc > @@ -20,17 +20,17 @@ > > static const struct test_f_f_data getpayload_test_data[] = > { > - TEST_fp_f (getpayload, plus_infty, IGNORE, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), > - TEST_fp_f (getpayload, minus_infty, IGNORE, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), > - TEST_fp_f (getpayload, plus_zero, IGNORE, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), > - TEST_fp_f (getpayload, minus_zero, IGNORE, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), > - TEST_fp_f (getpayload, 1000, IGNORE, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), > - TEST_fp_f (getpayload, max_value, IGNORE, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), > - TEST_fp_f (getpayload, -max_value, IGNORE, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), > - TEST_fp_f (getpayload, min_value, IGNORE, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), > - TEST_fp_f (getpayload, -min_value, IGNORE, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), > - TEST_fp_f (getpayload, min_subnorm_value, IGNORE, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), > - TEST_fp_f (getpayload, -min_subnorm_value, IGNORE, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), > + TEST_fp_f (getpayload, plus_infty, -1.0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), > + TEST_fp_f (getpayload, minus_infty, -1.0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), > + TEST_fp_f (getpayload, plus_zero, -1.0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), > + TEST_fp_f (getpayload, minus_zero, -1.0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), > + TEST_fp_f (getpayload, 1000, -1.0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), > + TEST_fp_f (getpayload, max_value, -1.0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), > + TEST_fp_f (getpayload, -max_value, -1.0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), > + TEST_fp_f (getpayload, min_value, -1.0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), > + TEST_fp_f (getpayload, -min_value, -1.0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), > + TEST_fp_f (getpayload, min_subnorm_value, -1.0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), > + TEST_fp_f (getpayload, -min_subnorm_value, -1.0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), OK. Add test for variants. > #if HIGH_ORDER_BIT_IS_SET_FOR_SNAN > TEST_fp_f (getpayload, snan_value_pl ("0x0"), plus_zero, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), > TEST_fp_f (getpayload, -snan_value_pl ("0x0"), plus_zero, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), > diff --git a/sysdeps/ieee754/dbl-64/s_getpayload.c b/sysdeps/ieee754/dbl-64/s_getpayload.c > index 3ab89ddd66..5a055be35a 100644 > --- a/sysdeps/ieee754/dbl-64/s_getpayload.c > +++ b/sysdeps/ieee754/dbl-64/s_getpayload.c > @@ -27,6 +27,9 @@ __getpayload (const double *x) > { > uint32_t hx, lx; > EXTRACT_WORDS (hx, lx, *x); > + if ((hx & 0x7ff00000) != 0x7ff00000 > + || ((hx & 0xfffff) | lx) == 0) > + return -1; OK. > hx &= 0x7ffff; > uint64_t ix = ((uint64_t) hx << 32) | lx; > if (FIX_INT_FP_CONVERT_ZERO && ix == 0) > diff --git a/sysdeps/ieee754/dbl-64/wordsize-64/s_getpayload.c b/sysdeps/ieee754/dbl-64/wordsize-64/s_getpayload.c > index 2c887b93b7..eba96d0c77 100644 > --- a/sysdeps/ieee754/dbl-64/wordsize-64/s_getpayload.c > +++ b/sysdeps/ieee754/dbl-64/wordsize-64/s_getpayload.c > @@ -26,6 +26,9 @@ __getpayload (const double *x) > { > uint64_t ix; > EXTRACT_WORDS64 (ix, *x); > + if ((ix & 0x7ff0000000000000ULL) != 0x7ff0000000000000ULL > + || (ix & 0xfffffffffffffULL) == 0) > + return -1; OK. > ix &= 0x7ffffffffffffULL; > return (double) ix; > } > diff --git a/sysdeps/ieee754/flt-32/s_getpayloadf.c b/sysdeps/ieee754/flt-32/s_getpayloadf.c > index e1d22473ff..1baad4847e 100644 > --- a/sysdeps/ieee754/flt-32/s_getpayloadf.c > +++ b/sysdeps/ieee754/flt-32/s_getpayloadf.c > @@ -27,6 +27,9 @@ __getpayloadf (const float *x) > { > uint32_t ix; > GET_FLOAT_WORD (ix, *x); > + if ((ix & 0x7f800000) != 0x7f800000 > + || (ix & 0x7fffff) == 0) > + return -1; OK. > ix &= 0x3fffff; > if (FIX_INT_FP_CONVERT_ZERO && ix == 0) > return 0.0f; > diff --git a/sysdeps/ieee754/ldbl-128/s_getpayloadl.c b/sysdeps/ieee754/ldbl-128/s_getpayloadl.c > index db55a00f66..1fbe704608 100644 > --- a/sysdeps/ieee754/ldbl-128/s_getpayloadl.c > +++ b/sysdeps/ieee754/ldbl-128/s_getpayloadl.c > @@ -26,6 +26,9 @@ __getpayloadl (const _Float128 *x) > { > uint64_t hx, lx; > GET_LDOUBLE_WORDS64 (hx, lx, *x); > + if ((hx & 0x7fff000000000000ULL) != 0x7fff000000000000ULL > + || ((hx & 0xffffffffffffULL) | lx) == 0) > + return -1; OK. > hx &= 0x7fffffffffffULL; > /* Construct the representation of the return value directly, since > 128-bit integers may not be available. */ > diff --git a/sysdeps/ieee754/ldbl-128ibm/s_getpayloadl.c b/sysdeps/ieee754/ldbl-128ibm/s_getpayloadl.c > index 3b5a1a8414..abbd694eea 100644 > --- a/sysdeps/ieee754/ldbl-128ibm/s_getpayloadl.c > +++ b/sysdeps/ieee754/ldbl-128ibm/s_getpayloadl.c > @@ -27,6 +27,9 @@ __getpayloadl (const long double *x) > double xhi = ldbl_high (*x); > uint64_t ix; > EXTRACT_WORDS64 (ix, xhi); > + if ((ix & 0x7ff0000000000000ULL) != 0x7ff0000000000000ULL > + || (ix & 0xfffffffffffffULL) == 0) > + return -1; OK. > ix &= 0x7ffffffffffffULL; > if (FIX_INT_FP_CONVERT_ZERO && ix == 0) > return 0.0L; > diff --git a/sysdeps/ieee754/ldbl-96/s_getpayloadl.c b/sysdeps/ieee754/ldbl-96/s_getpayloadl.c > index 8f09cb74c8..761bd69b58 100644 > --- a/sysdeps/ieee754/ldbl-96/s_getpayloadl.c > +++ b/sysdeps/ieee754/ldbl-96/s_getpayloadl.c > @@ -27,6 +27,9 @@ __getpayloadl (const long double *x) > uint16_t se __attribute__ ((unused)); > uint32_t hx, lx; > GET_LDOUBLE_WORDS (se, hx, lx, *x); > + if ((se & 0x7fff) != 0x7fff > + || ((hx & 0x7fffffff) | lx) == 0) > + return -1; OK. > hx &= 0x3fffffff; > uint64_t ix = ((uint64_t) hx << 32) | lx; > return (long double) ix; >
diff --git a/manual/arith.texi b/manual/arith.texi index 89c2c064f1..75eaf67fe7 100644 --- a/manual/arith.texi +++ b/manual/arith.texi @@ -1895,9 +1895,10 @@ propagated from NaN inputs to the result of a floating-point operation. These functions, defined by TS 18661-1:2014 and TS 18661-3:2015, return the payload of the NaN pointed to by @var{x} (returned as a positive integer, or positive zero, represented as a -floating-point number); if @var{x} is not a NaN, they return an -unspecified value. They raise no floating-point exceptions even for -signaling NaNs. +floating-point number); if @var{x} is not a NaN, they return +@minus{}1. They raise no floating-point exceptions even for signaling +NaNs. (The return value of @minus{}1 for an argument that is not a +NaN is specified in C2x; the value was unspecified in TS 18661.) @end deftypefun @deftypefun int setpayload (double *@var{x}, double @var{payload}) diff --git a/math/libm-test-getpayload.inc b/math/libm-test-getpayload.inc index bd660471aa..72e3c19d1e 100644 --- a/math/libm-test-getpayload.inc +++ b/math/libm-test-getpayload.inc @@ -20,17 +20,17 @@ static const struct test_f_f_data getpayload_test_data[] = { - TEST_fp_f (getpayload, plus_infty, IGNORE, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), - TEST_fp_f (getpayload, minus_infty, IGNORE, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), - TEST_fp_f (getpayload, plus_zero, IGNORE, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), - TEST_fp_f (getpayload, minus_zero, IGNORE, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), - TEST_fp_f (getpayload, 1000, IGNORE, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), - TEST_fp_f (getpayload, max_value, IGNORE, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), - TEST_fp_f (getpayload, -max_value, IGNORE, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), - TEST_fp_f (getpayload, min_value, IGNORE, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), - TEST_fp_f (getpayload, -min_value, IGNORE, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), - TEST_fp_f (getpayload, min_subnorm_value, IGNORE, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), - TEST_fp_f (getpayload, -min_subnorm_value, IGNORE, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), + TEST_fp_f (getpayload, plus_infty, -1.0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), + TEST_fp_f (getpayload, minus_infty, -1.0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), + TEST_fp_f (getpayload, plus_zero, -1.0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), + TEST_fp_f (getpayload, minus_zero, -1.0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), + TEST_fp_f (getpayload, 1000, -1.0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), + TEST_fp_f (getpayload, max_value, -1.0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), + TEST_fp_f (getpayload, -max_value, -1.0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), + TEST_fp_f (getpayload, min_value, -1.0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), + TEST_fp_f (getpayload, -min_value, -1.0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), + TEST_fp_f (getpayload, min_subnorm_value, -1.0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), + TEST_fp_f (getpayload, -min_subnorm_value, -1.0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), #if HIGH_ORDER_BIT_IS_SET_FOR_SNAN TEST_fp_f (getpayload, snan_value_pl ("0x0"), plus_zero, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), TEST_fp_f (getpayload, -snan_value_pl ("0x0"), plus_zero, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), diff --git a/sysdeps/ieee754/dbl-64/s_getpayload.c b/sysdeps/ieee754/dbl-64/s_getpayload.c index 3ab89ddd66..5a055be35a 100644 --- a/sysdeps/ieee754/dbl-64/s_getpayload.c +++ b/sysdeps/ieee754/dbl-64/s_getpayload.c @@ -27,6 +27,9 @@ __getpayload (const double *x) { uint32_t hx, lx; EXTRACT_WORDS (hx, lx, *x); + if ((hx & 0x7ff00000) != 0x7ff00000 + || ((hx & 0xfffff) | lx) == 0) + return -1; hx &= 0x7ffff; uint64_t ix = ((uint64_t) hx << 32) | lx; if (FIX_INT_FP_CONVERT_ZERO && ix == 0) diff --git a/sysdeps/ieee754/dbl-64/wordsize-64/s_getpayload.c b/sysdeps/ieee754/dbl-64/wordsize-64/s_getpayload.c index 2c887b93b7..eba96d0c77 100644 --- a/sysdeps/ieee754/dbl-64/wordsize-64/s_getpayload.c +++ b/sysdeps/ieee754/dbl-64/wordsize-64/s_getpayload.c @@ -26,6 +26,9 @@ __getpayload (const double *x) { uint64_t ix; EXTRACT_WORDS64 (ix, *x); + if ((ix & 0x7ff0000000000000ULL) != 0x7ff0000000000000ULL + || (ix & 0xfffffffffffffULL) == 0) + return -1; ix &= 0x7ffffffffffffULL; return (double) ix; } diff --git a/sysdeps/ieee754/flt-32/s_getpayloadf.c b/sysdeps/ieee754/flt-32/s_getpayloadf.c index e1d22473ff..1baad4847e 100644 --- a/sysdeps/ieee754/flt-32/s_getpayloadf.c +++ b/sysdeps/ieee754/flt-32/s_getpayloadf.c @@ -27,6 +27,9 @@ __getpayloadf (const float *x) { uint32_t ix; GET_FLOAT_WORD (ix, *x); + if ((ix & 0x7f800000) != 0x7f800000 + || (ix & 0x7fffff) == 0) + return -1; ix &= 0x3fffff; if (FIX_INT_FP_CONVERT_ZERO && ix == 0) return 0.0f; diff --git a/sysdeps/ieee754/ldbl-128/s_getpayloadl.c b/sysdeps/ieee754/ldbl-128/s_getpayloadl.c index db55a00f66..1fbe704608 100644 --- a/sysdeps/ieee754/ldbl-128/s_getpayloadl.c +++ b/sysdeps/ieee754/ldbl-128/s_getpayloadl.c @@ -26,6 +26,9 @@ __getpayloadl (const _Float128 *x) { uint64_t hx, lx; GET_LDOUBLE_WORDS64 (hx, lx, *x); + if ((hx & 0x7fff000000000000ULL) != 0x7fff000000000000ULL + || ((hx & 0xffffffffffffULL) | lx) == 0) + return -1; hx &= 0x7fffffffffffULL; /* Construct the representation of the return value directly, since 128-bit integers may not be available. */ diff --git a/sysdeps/ieee754/ldbl-128ibm/s_getpayloadl.c b/sysdeps/ieee754/ldbl-128ibm/s_getpayloadl.c index 3b5a1a8414..abbd694eea 100644 --- a/sysdeps/ieee754/ldbl-128ibm/s_getpayloadl.c +++ b/sysdeps/ieee754/ldbl-128ibm/s_getpayloadl.c @@ -27,6 +27,9 @@ __getpayloadl (const long double *x) double xhi = ldbl_high (*x); uint64_t ix; EXTRACT_WORDS64 (ix, xhi); + if ((ix & 0x7ff0000000000000ULL) != 0x7ff0000000000000ULL + || (ix & 0xfffffffffffffULL) == 0) + return -1; ix &= 0x7ffffffffffffULL; if (FIX_INT_FP_CONVERT_ZERO && ix == 0) return 0.0L; diff --git a/sysdeps/ieee754/ldbl-96/s_getpayloadl.c b/sysdeps/ieee754/ldbl-96/s_getpayloadl.c index 8f09cb74c8..761bd69b58 100644 --- a/sysdeps/ieee754/ldbl-96/s_getpayloadl.c +++ b/sysdeps/ieee754/ldbl-96/s_getpayloadl.c @@ -27,6 +27,9 @@ __getpayloadl (const long double *x) uint16_t se __attribute__ ((unused)); uint32_t hx, lx; GET_LDOUBLE_WORDS (se, hx, lx, *x); + if ((se & 0x7fff) != 0x7fff + || ((hx & 0x7fffffff) | lx) == 0) + return -1; hx &= 0x3fffffff; uint64_t ix = ((uint64_t) hx << 32) | lx; return (long double) ix;