diff options
Diffstat (limited to 'fpu/softfloat.c')
| -rw-r--r-- | fpu/softfloat.c | 66 |
1 files changed, 60 insertions, 6 deletions
diff --git a/fpu/softfloat.c b/fpu/softfloat.c index 26f3a8d..f4fed9b 100644 --- a/fpu/softfloat.c +++ b/fpu/softfloat.c @@ -404,12 +404,16 @@ float64_gen2(float64 xa, float64 xb, float_status *s, /* * Classify a floating point number. Everything above float_class_qnan * is a NaN so cls >= float_class_qnan is any NaN. + * + * Note that we canonicalize denormals, so most code should treat + * class_normal and class_denormal identically. */ typedef enum __attribute__ ((__packed__)) { float_class_unclassified, float_class_zero, float_class_normal, + float_class_denormal, /* input was a non-squashed denormal */ float_class_inf, float_class_qnan, /* all NaNs from here */ float_class_snan, @@ -420,12 +424,14 @@ typedef enum __attribute__ ((__packed__)) { enum { float_cmask_zero = float_cmask(float_class_zero), float_cmask_normal = float_cmask(float_class_normal), + float_cmask_denormal = float_cmask(float_class_denormal), float_cmask_inf = float_cmask(float_class_inf), float_cmask_qnan = float_cmask(float_class_qnan), float_cmask_snan = float_cmask(float_class_snan), float_cmask_infzero = float_cmask_zero | float_cmask_inf, float_cmask_anynan = float_cmask_qnan | float_cmask_snan, + float_cmask_anynorm = float_cmask_normal | float_cmask_denormal, }; /* Flags for parts_minmax. */ @@ -460,6 +466,20 @@ static inline __attribute__((unused)) bool is_qnan(FloatClass c) } /* + * Return true if the float_cmask has only normals in it + * (including input denormals that were canonicalized) + */ +static inline bool cmask_is_only_normals(int cmask) +{ + return !(cmask & ~float_cmask_anynorm); +} + +static inline bool is_anynorm(FloatClass c) +{ + return float_cmask(c) & float_cmask_anynorm; +} + +/* * Structure holding all of the decomposed parts of a float. * The exponent is unbiased and the fraction is normalized. * @@ -1729,6 +1749,7 @@ static float64 float64r32_round_pack_canonical(FloatParts64 *p, */ switch (p->cls) { case float_class_normal: + case float_class_denormal: if (unlikely(p->exp == 0)) { /* * The result is denormal for float32, but can be represented @@ -1817,6 +1838,7 @@ static floatx80 floatx80_round_pack_canonical(FloatParts128 *p, switch (p->cls) { case float_class_normal: + case float_class_denormal: if (s->floatx80_rounding_precision == floatx80_precision_x) { parts_uncanon_normal(p, s, fmt); frac = p->frac_hi; @@ -2696,6 +2718,9 @@ static void parts_float_to_ahp(FloatParts64 *a, float_status *s) float16_params_ahp.frac_size + 1); break; + case float_class_denormal: + float_raise(float_flag_input_denormal_used, s); + break; case float_class_normal: case float_class_zero: break; @@ -2710,6 +2735,9 @@ static void parts64_float_to_float(FloatParts64 *a, float_status *s) if (is_nan(a->cls)) { parts_return_nan(a, s); } + if (a->cls == float_class_denormal) { + float_raise(float_flag_input_denormal_used, s); + } } static void parts128_float_to_float(FloatParts128 *a, float_status *s) @@ -2717,6 +2745,9 @@ static void parts128_float_to_float(FloatParts128 *a, float_status *s) if (is_nan(a->cls)) { parts_return_nan(a, s); } + if (a->cls == float_class_denormal) { + float_raise(float_flag_input_denormal_used, s); + } } #define parts_float_to_float(P, S) \ @@ -2729,12 +2760,21 @@ static void parts_float_to_float_narrow(FloatParts64 *a, FloatParts128 *b, a->sign = b->sign; a->exp = b->exp; - if (a->cls == float_class_normal) { + switch (a->cls) { + case float_class_denormal: + float_raise(float_flag_input_denormal_used, s); + /* fall through */ + case float_class_normal: frac_truncjam(a, b); - } else if (is_nan(a->cls)) { + break; + case float_class_snan: + case float_class_qnan: /* Discard the low bits of the NaN. */ a->frac = b->frac_hi; parts_return_nan(a, s); + break; + default: + break; } } @@ -2749,6 +2789,9 @@ static void parts_float_to_float_widen(FloatParts128 *a, FloatParts64 *b, if (is_nan(a->cls)) { parts_return_nan(a, s); } + if (a->cls == float_class_denormal) { + float_raise(float_flag_input_denormal_used, s); + } } float32 float16_to_float32(float16 a, bool ieee, float_status *s) @@ -3218,6 +3261,7 @@ static Int128 float128_to_int128_scalbn(float128 a, FloatRoundMode rmode, return int128_zero(); case float_class_normal: + case float_class_denormal: if (parts_round_to_int_normal(&p, rmode, scale, 128 - 2)) { flags = float_flag_inexact; } @@ -3645,6 +3689,7 @@ static Int128 float128_to_uint128_scalbn(float128 a, FloatRoundMode rmode, return int128_zero(); case float_class_normal: + case float_class_denormal: if (parts_round_to_int_normal(&p, rmode, scale, 128 - 2)) { flags = float_flag_inexact; if (p.cls == float_class_zero) { @@ -4386,7 +4431,11 @@ float32_hs_compare(float32 xa, float32 xb, float_status *s, bool is_quiet) goto soft; } - float32_input_flush2(&ua.s, &ub.s, s); + if (unlikely(float32_is_denormal(ua.s) || float32_is_denormal(ub.s))) { + /* We may need to set the input_denormal_used flag */ + goto soft; + } + if (isgreaterequal(ua.h, ub.h)) { if (isgreater(ua.h, ub.h)) { return float_relation_greater; @@ -4436,7 +4485,11 @@ float64_hs_compare(float64 xa, float64 xb, float_status *s, bool is_quiet) goto soft; } - float64_input_flush2(&ua.s, &ub.s, s); + if (unlikely(float64_is_denormal(ua.s) || float64_is_denormal(ub.s))) { + /* We may need to set the input_denormal_used flag */ + goto soft; + } + if (isgreaterequal(ua.h, ub.h)) { if (isgreater(ua.h, ub.h)) { return float_relation_greater; @@ -5231,6 +5284,8 @@ float32 float32_exp2(float32 a, float_status *status) float32_unpack_canonical(&xp, a, status); if (unlikely(xp.cls != float_class_normal)) { switch (xp.cls) { + case float_class_denormal: + break; case float_class_snan: case float_class_qnan: parts_return_nan(&xp, status); @@ -5240,9 +5295,8 @@ float32 float32_exp2(float32 a, float_status *status) case float_class_zero: return float32_one; default: - break; + g_assert_not_reached(); } - g_assert_not_reached(); } float_raise(float_flag_inexact, status); |