@samitouri / QOSamiQemu / commits / 24b46e7bb7

fpu: Return struct from parts{64,128}_addsub

At the same time, export. Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

Richard Henderson committed Apr 26, 2026 at 17:09 UTC 24b46e7bb731a99cb0fd58ad4e79d950d9e47a24
3 files changed +43 -37
fpu/softfloat-parts.c.inc
+23 -22
@@ -524,11 +524,11 @@ static void partsN(uncanon)(FloatPartsN *p, float_status *s,
524 * according to the IEC/IEEE Standard for Binary Floating-Point
525 * Arithmetic.
526 */
527 -static FloatPartsN *partsN(addsub)(FloatPartsN *a, FloatPartsN *b,
528 - float_status *s, bool subtract)
527 +FloatPartsN partsN(addsub)(const FloatPartsN *a_orig,
528 + const FloatPartsN *b_orig,
529 + float_status *s, bool subtract)
530 {
530 - bool b_sign = b->sign ^ subtract;
531 - int ab_mask = float_cmask(a->cls) | float_cmask(b->cls);
531 + int ab_mask = float_cmask(a_orig->cls) | float_cmask(b_orig->cls);
532
533 /*
534 * For addition and subtraction, we will consume an
@@ -538,10 +538,15 @@ static FloatPartsN *partsN(addsub)(FloatPartsN *a, FloatPartsN *b,
538 record_denormals_used(ab_mask, s);
539 }
540
541 - if (a->sign != b_sign) {
541 + FloatPartsN a = *a_orig;
542 + FloatPartsN b = *b_orig;
543 +
544 + b.sign ^= subtract;
545 +
546 + if (a.sign != b.sign) {
547 /* Subtraction */
548 if (likely(cmask_is_only_normals(ab_mask))) {
544 - if (partsN(sub_normal)(a, b)) {
549 + if (partsN(sub_normal)(&a, &b)) {
550 return a;
551 }
552 /* Subtract was exact, fall through to set sign. */
@@ -549,7 +554,7 @@ static FloatPartsN *partsN(addsub)(FloatPartsN *a, FloatPartsN *b,
554 }
555
556 if (ab_mask == float_cmask_zero) {
552 - a->sign = s->float_rounding_mode == float_round_down;
557 + a.sign = s->float_rounding_mode == float_round_down;
558 return a;
559 }
560
@@ -558,23 +563,22 @@ static FloatPartsN *partsN(addsub)(FloatPartsN *a, FloatPartsN *b,
563 }
564
565 if (ab_mask & float_cmask_inf) {
561 - if (a->cls != float_class_inf) {
566 + if (a.cls != float_class_inf) {
567 /* N - Inf */
563 - goto return_b;
568 + return b;
569 }
565 - if (b->cls != float_class_inf) {
570 + if (b.cls != float_class_inf) {
571 /* Inf - N */
572 return a;
573 }
574 /* Inf - Inf */
575 float_raise(float_flag_invalid | float_flag_invalid_isi, s);
571 - *a = partsN(default_nan)(s);
572 - return a;
576 + return partsN(default_nan)(s);
577 }
578 } else {
579 /* Addition */
580 if (likely(cmask_is_only_normals(ab_mask))) {
577 - partsN(add_normal)(a, b);
581 + partsN(add_normal)(&a, &b);
582 return a;
583 }
584
@@ -587,25 +591,22 @@ static FloatPartsN *partsN(addsub)(FloatPartsN *a, FloatPartsN *b,
591 }
592
593 if (ab_mask & float_cmask_inf) {
590 - a->cls = float_class_inf;
594 + a.cls = float_class_inf;
595 return a;
596 }
597 }
598
595 - if (b->cls == float_class_zero) {
596 - g_assert(is_anynorm(a->cls));
599 + if (b.cls == float_class_zero) {
600 + g_assert(is_anynorm(a.cls));
601 return a;
602 }
603
600 - g_assert(a->cls == float_class_zero);
601 - g_assert(is_anynorm(b->cls));
602 - return_b:
603 - b->sign = b_sign;
604 + g_assert(a.cls == float_class_zero);
605 + g_assert(is_anynorm(b.cls));
606 return b;
607
608 p_nan:
607 - *a = partsN(pick_nan)(a, b, s);
608 - return a;
609 + return partsN(pick_nan)(a_orig, b_orig, s);
610 }
611
612 /*
fpu/softfloat.c
+15 -15
@@ -1582,9 +1582,9 @@ float16_addsub(float16 a, float16 b, float_status *status, bool subtract)
1582 {
1583 FloatParts64 pa = float16_unpack_canonical(a, status);
1584 FloatParts64 pb = float16_unpack_canonical(b, status);
1585 - FloatParts64 *pr = parts64_addsub(&pa, &pb, status, subtract);
1585 + FloatParts64 pr = parts64_addsub(&pa, &pb, status, subtract);
1586
1587 - return float16_round_pack_canonical(pr, status);
1587 + return float16_round_pack_canonical(&pr, status);
1588 }
1589
1590 float16 float16_add(float16 a, float16 b, float_status *status)
@@ -1602,9 +1602,9 @@ soft_f32_addsub(float32 a, float32 b, float_status *status, bool subtract)
1602 {
1603 FloatParts64 pa = float32_unpack_canonical(a, status);
1604 FloatParts64 pb = float32_unpack_canonical(b, status);
1605 - FloatParts64 *pr = parts64_addsub(&pa, &pb, status, subtract);
1605 + FloatParts64 pr = parts64_addsub(&pa, &pb, status, subtract);
1606
1607 - return float32_round_pack_canonical(pr, status);
1607 + return float32_round_pack_canonical(&pr, status);
1608 }
1609
1610 static float32 soft_f32_add(float32 a, float32 b, float_status *status)
@@ -1622,9 +1622,9 @@ soft_f64_addsub(float64 a, float64 b, float_status *status, bool subtract)
1622 {
1623 FloatParts64 pa = float64_unpack_canonical(a, status);
1624 FloatParts64 pb = float64_unpack_canonical(b, status);
1625 - FloatParts64 *pr = parts64_addsub(&pa, &pb, status, subtract);
1625 + FloatParts64 pr = parts64_addsub(&pa, &pb, status, subtract);
1626
1627 - return float64_round_pack_canonical(pr, status);
1627 + return float64_round_pack_canonical(&pr, status);
1628 }
1629
1630 static float64 soft_f64_add(float64 a, float64 b, float_status *status)
@@ -1717,9 +1717,9 @@ static float64 float64r32_addsub(float64 a, float64 b, float_status *status,
1717 {
1718 FloatParts64 pa = float64_unpack_canonical(a, status);
1719 FloatParts64 pb = float64_unpack_canonical(b, status);
1720 - FloatParts64 *pr = parts64_addsub(&pa, &pb, status, subtract);
1720 + FloatParts64 pr = parts64_addsub(&pa, &pb, status, subtract);
1721
1722 - return float64r32_round_pack_canonical(pr, status);
1722 + return float64r32_round_pack_canonical(&pr, status);
1723 }
1724
1725 float64 float64r32_add(float64 a, float64 b, float_status *status)
@@ -1737,9 +1737,9 @@ bfloat16_addsub(bfloat16 a, bfloat16 b, float_status *status, bool subtract)
1737 {
1738 FloatParts64 pa = bfloat16_unpack_canonical(a, status);
1739 FloatParts64 pb = bfloat16_unpack_canonical(b, status);
1740 - FloatParts64 *pr = parts64_addsub(&pa, &pb, status, subtract);
1740 + FloatParts64 pr = parts64_addsub(&pa, &pb, status, subtract);
1741
1742 - return bfloat16_round_pack_canonical(pr, status);
1742 + return bfloat16_round_pack_canonical(&pr, status);
1743 }
1744
1745 bfloat16 bfloat16_add(bfloat16 a, bfloat16 b, float_status *status)
@@ -1757,9 +1757,9 @@ float128_addsub(float128 a, float128 b, float_status *status, bool subtract)
1757 {
1758 FloatParts128 pa = float128_unpack_canonical(a, status);
1759 FloatParts128 pb = float128_unpack_canonical(b, status);
1760 - FloatParts128 *pr = parts128_addsub(&pa, &pb, status, subtract);
1760 + FloatParts128 pr = parts128_addsub(&pa, &pb, status, subtract);
1761
1762 - return float128_round_pack_canonical(pr, status);
1762 + return float128_round_pack_canonical(&pr, status);
1763 }
1764
1765 float128 float128_add(float128 a, float128 b, float_status *status)
@@ -1775,15 +1775,15 @@ float128 float128_sub(float128 a, float128 b, float_status *status)
1775 static floatx80 QEMU_FLATTEN
1776 floatx80_addsub(floatx80 a, floatx80 b, float_status *status, bool subtract)
1777 {
1778 - FloatParts128 pa, pb, *pr;
1778 + FloatParts128 pa, pb;
1779
1780 if (!floatx80_unpack_canonical(&pa, a, status) ||
1781 !floatx80_unpack_canonical(&pb, b, status)) {
1782 return floatx80_default_nan(status);
1783 }
1784
1785 - pr = parts128_addsub(&pa, &pb, status, subtract);
1786 - return floatx80_round_pack_canonical(pr, status);
1785 + pa = parts128_addsub(&pa, &pb, status, subtract);
1786 + return floatx80_round_pack_canonical(&pa, status);
1787 }
1788
1789 floatx80 floatx80_add(floatx80 a, floatx80 b, float_status *status)
include/fpu/softfloat-parts.h
+5
@@ -182,6 +182,11 @@ FloatParts128 parts128_return_nan(const FloatParts128 *a, float_status *s);
182 * Operations
183 */
184
185 +FloatParts64 parts64_addsub(const FloatParts64 *a, const FloatParts64 *b,
186 + float_status *s, bool subtract);
187 +FloatParts128 parts128_addsub(const FloatParts128 *a, const FloatParts128 *b,
188 + float_status *s, bool subtract);
189 +
190 FloatRelation parts64_compare(const FloatParts64 *a, const FloatParts64 *b,
191 float_status *s, bool quiet);
192 FloatRelation parts128_compare(const FloatParts128 *a, const FloatParts128 *b,