cachepc-qemu

Fork of AMDESE/qemu with changes for cachepc side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-qemu
Log | Files | Refs | Submodules | LICENSE | sfeed.txt

softfloat-parts-addsub.c.inc (1674B)

      1/*
      2 * Floating point arithmetic implementation
      3 *
      4 * The code in this source file is derived from release 2a of the SoftFloat
      5 * IEC/IEEE Floating-point Arithmetic Package. Those parts of the code (and
      6 * some later contributions) are provided under that license, as detailed below.
      7 * It has subsequently been modified by contributors to the QEMU Project,
      8 * so some portions are provided under:
      9 *  the SoftFloat-2a license
     10 *  the BSD license
     11 *  GPL-v2-or-later
     12 *
     13 * Any future contributions to this file after December 1st 2014 will be
     14 * taken to be licensed under the Softfloat-2a license unless specifically
     15 * indicated otherwise.
     16 */
     17
     18static void partsN(add_normal)(FloatPartsN *a, FloatPartsN *b)
     19{
     20    int exp_diff = a->exp - b->exp;
     21
     22    if (exp_diff > 0) {
     23        frac_shrjam(b, exp_diff);
     24    } else if (exp_diff < 0) {
     25        frac_shrjam(a, -exp_diff);
     26        a->exp = b->exp;
     27    }
     28
     29    if (frac_add(a, a, b)) {
     30        frac_shrjam(a, 1);
     31        a->frac_hi |= DECOMPOSED_IMPLICIT_BIT;
     32        a->exp += 1;
     33    }
     34}
     35
     36static bool partsN(sub_normal)(FloatPartsN *a, FloatPartsN *b)
     37{
     38    int exp_diff = a->exp - b->exp;
     39    int shift;
     40
     41    if (exp_diff > 0) {
     42        frac_shrjam(b, exp_diff);
     43        frac_sub(a, a, b);
     44    } else if (exp_diff < 0) {
     45        a->exp = b->exp;
     46        a->sign ^= 1;
     47        frac_shrjam(a, -exp_diff);
     48        frac_sub(a, b, a);
     49    } else if (frac_sub(a, a, b)) {
     50        /* Overflow means that A was less than B. */
     51        frac_neg(a);
     52        a->sign ^= 1;
     53    }
     54
     55    shift = frac_normalize(a);
     56    if (likely(shift < N)) {
     57        a->exp -= shift;
     58	return true;
     59    }
     60    a->cls = float_class_zero;
     61    return false;
     62}