REAL_VALUE_TYPE &value,
const REAL_VALUE_TYPE &inf)
{
- const real_format *fmt = REAL_MODE_FORMAT (mode);
- REAL_VALUE_TYPE tmp;
- real_nextafter (&tmp, fmt, &value, &inf);
- value = tmp;
+ if (MODE_COMPOSITE_P (mode)
+ && (real_isdenormal (&value, mode) || real_iszero (&value)))
+ {
+ // IBM extended denormals only have DFmode precision.
+ REAL_VALUE_TYPE tmp, tmp2;
+ real_convert (&tmp2, DFmode, &value);
+ real_nextafter (&tmp, REAL_MODE_FORMAT (DFmode), &tmp2, &inf);
+ real_convert (&value, mode, &tmp);
+ }
+ else
+ {
+ REAL_VALUE_TYPE tmp;
+ real_nextafter (&tmp, REAL_MODE_FORMAT (mode), &value, &inf);
+ value = tmp;
+ }
}
// Like real_arithmetic, but round the result to INF if the operation
}
if (round && (inexact || !real_identical (&result, &value)))
{
- if (mode_composite)
+ if (mode_composite
+ && (real_isdenormal (&result, mode) || real_iszero (&result)))
{
- if (real_isdenormal (&result, mode)
- || real_iszero (&result))
- {
- // IBM extended denormals only have DFmode precision.
- REAL_VALUE_TYPE tmp;
- real_convert (&tmp, DFmode, &value);
- frange_nextafter (DFmode, tmp, inf);
- real_convert (&result, mode, &tmp);
- return;
- }
+ // IBM extended denormals only have DFmode precision.
+ REAL_VALUE_TYPE tmp, tmp2;
+ real_convert (&tmp2, DFmode, &value);
+ real_nextafter (&tmp, REAL_MODE_FORMAT (DFmode), &tmp2, &inf);
+ real_convert (&result, mode, &tmp);
}
- frange_nextafter (mode, result, inf);
+ else
+ frange_nextafter (mode, result, inf);
}
+ if (mode_composite)
+ switch (code)
+ {
+ case PLUS_EXPR:
+ case MINUS_EXPR:
+ // ibm-ldouble-format documents 1ulp for + and -.
+ frange_nextafter (mode, result, inf);
+ break;
+ case MULT_EXPR:
+ // ibm-ldouble-format documents 2ulps for *.
+ frange_nextafter (mode, result, inf);
+ frange_nextafter (mode, result, inf);
+ break;
+ case RDIV_EXPR:
+ // ibm-ldouble-format documents 3ulps for /.
+ frange_nextafter (mode, result, inf);
+ frange_nextafter (mode, result, inf);
+ frange_nextafter (mode, result, inf);
+ break;
+ default:
+ break;
+ }
}
// Crop R to [-INF, MAX] where MAX is the maximum representable number