* [PATCH 1/3] fpu/softfloat: Define operations for bfloat16
2020-08-13 7:14 [PATCH 0/3] Implement blfoat16 in softfloat LIU Zhiwei
@ 2020-08-13 7:14 ` LIU Zhiwei
2020-08-13 7:14 ` [PATCH 2/3] fpu/softfloat: Define convert " LIU Zhiwei
` (2 subsequent siblings)
3 siblings, 0 replies; 5+ messages in thread
From: LIU Zhiwei @ 2020-08-13 7:14 UTC (permalink / raw)
To: qemu-devel
Cc: alex.bennee, richard.henderson, LIU Zhiwei, aurelien,
peter.maydell
This patch implements operations for bfloat16 except conversion and some misc
operations. We also add FloatFmt and pack/unpack interfaces for bfloat16.
As they are both static fields, we can't make a sperate patch for them.
Signed-off-by: LIU Zhiwei <zhiwei_liu@c-sky.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
---
fpu/softfloat.c | 168 ++++++++++++++++++++++++++++++++++
include/fpu/softfloat-types.h | 5 +
include/fpu/softfloat.h | 44 +++++++++
3 files changed, 217 insertions(+)
diff --git a/fpu/softfloat.c b/fpu/softfloat.c
index 79be4f5840..d4205f92d5 100644
--- a/fpu/softfloat.c
+++ b/fpu/softfloat.c
@@ -554,6 +554,10 @@ static const FloatFmt float16_params_ahp = {
.arm_althp = true
};
+static const FloatFmt bfloat16_params = {
+ FLOAT_PARAMS(8, 7)
+};
+
static const FloatFmt float32_params = {
FLOAT_PARAMS(8, 23)
};
@@ -580,6 +584,11 @@ static inline FloatParts float16_unpack_raw(float16 f)
return unpack_raw(float16_params, f);
}
+static inline FloatParts bfloat16_unpack_raw(bfloat16 f)
+{
+ return unpack_raw(bfloat16_params, f);
+}
+
static inline FloatParts float32_unpack_raw(float32 f)
{
return unpack_raw(float32_params, f);
@@ -603,6 +612,11 @@ static inline float16 float16_pack_raw(FloatParts p)
return make_float16(pack_raw(float16_params, p));
}
+static inline bfloat16 bfloat16_pack_raw(FloatParts p)
+{
+ return pack_raw(bfloat16_params, p);
+}
+
static inline float32 float32_pack_raw(FloatParts p)
{
return make_float32(pack_raw(float32_params, p));
@@ -820,6 +834,11 @@ static FloatParts float16_unpack_canonical(float16 f, float_status *s)
return float16a_unpack_canonical(f, s, &float16_params);
}
+static FloatParts bfloat16_unpack_canonical(bfloat16 f, float_status *s)
+{
+ return sf_canonicalize(bfloat16_unpack_raw(f), &bfloat16_params, s);
+}
+
static float16 float16a_round_pack_canonical(FloatParts p, float_status *s,
const FloatFmt *params)
{
@@ -831,6 +850,11 @@ static float16 float16_round_pack_canonical(FloatParts p, float_status *s)
return float16a_round_pack_canonical(p, s, &float16_params);
}
+static bfloat16 bfloat16_round_pack_canonical(FloatParts p, float_status *s)
+{
+ return bfloat16_pack_raw(round_canonical(p, s, &bfloat16_params));
+}
+
static FloatParts float32_unpack_canonical(float32 f, float_status *s)
{
return sf_canonicalize(float32_unpack_raw(f), &float32_params, s);
@@ -1158,6 +1182,28 @@ float64_sub(float64 a, float64 b, float_status *s)
return float64_addsub(a, b, s, hard_f64_sub, soft_f64_sub);
}
+/*
+ * Returns the result of adding or subtracting the bfloat16
+ * values `a' and `b'.
+ */
+bfloat16 QEMU_FLATTEN bfloat16_add(bfloat16 a, bfloat16 b, float_status *status)
+{
+ FloatParts pa = bfloat16_unpack_canonical(a, status);
+ FloatParts pb = bfloat16_unpack_canonical(b, status);
+ FloatParts pr = addsub_floats(pa, pb, false, status);
+
+ return bfloat16_round_pack_canonical(pr, status);
+}
+
+bfloat16 QEMU_FLATTEN bfloat16_sub(bfloat16 a, bfloat16 b, float_status *status)
+{
+ FloatParts pa = bfloat16_unpack_canonical(a, status);
+ FloatParts pb = bfloat16_unpack_canonical(b, status);
+ FloatParts pr = addsub_floats(pa, pb, true, status);
+
+ return bfloat16_round_pack_canonical(pr, status);
+}
+
/*
* Returns the result of multiplying the floating-point values `a' and
* `b'. The operation is performed according to the IEC/IEEE Standard
@@ -1260,6 +1306,20 @@ float64_mul(float64 a, float64 b, float_status *s)
f64_is_zon2, f64_addsubmul_post);
}
+/*
+ * Returns the result of multiplying the bfloat16
+ * values `a' and `b'.
+ */
+
+bfloat16 QEMU_FLATTEN bfloat16_mul(bfloat16 a, bfloat16 b, float_status *status)
+{
+ FloatParts pa = bfloat16_unpack_canonical(a, status);
+ FloatParts pb = bfloat16_unpack_canonical(b, status);
+ FloatParts pr = mul_floats(pa, pb, status);
+
+ return bfloat16_round_pack_canonical(pr, status);
+}
+
/*
* Returns the result of multiplying the floating-point values `a' and
* `b' then adding 'c', with no intermediate rounding step after the
@@ -1642,6 +1702,23 @@ float64_muladd(float64 xa, float64 xb, float64 xc, int flags, float_status *s)
return soft_f64_muladd(ua.s, ub.s, uc.s, flags, s);
}
+/*
+ * Returns the result of multiplying the bfloat16 values `a'
+ * and `b' then adding 'c', with no intermediate rounding step after the
+ * multiplication.
+ */
+
+bfloat16 QEMU_FLATTEN bfloat16_muladd(bfloat16 a, bfloat16 b, bfloat16 c,
+ int flags, float_status *status)
+{
+ FloatParts pa = bfloat16_unpack_canonical(a, status);
+ FloatParts pb = bfloat16_unpack_canonical(b, status);
+ FloatParts pc = bfloat16_unpack_canonical(c, status);
+ FloatParts pr = muladd_floats(pa, pb, pc, flags, status);
+
+ return bfloat16_round_pack_canonical(pr, status);
+}
+
/*
* Returns the result of dividing the floating-point value `a' by the
* corresponding value `b'. The operation is performed according to
@@ -1808,6 +1885,20 @@ float64_div(float64 a, float64 b, float_status *s)
f64_div_pre, f64_div_post);
}
+/*
+ * Returns the result of dividing the bfloat16
+ * value `a' by the corresponding value `b'.
+ */
+
+bfloat16 bfloat16_div(bfloat16 a, bfloat16 b, float_status *status)
+{
+ FloatParts pa = bfloat16_unpack_canonical(a, status);
+ FloatParts pb = bfloat16_unpack_canonical(b, status);
+ FloatParts pr = div_floats(pa, pb, status);
+
+ return bfloat16_round_pack_canonical(pr, status);
+}
+
/*
* Float to Float conversions
*
@@ -2847,6 +2938,25 @@ MINMAX(64, maxnummag, false, true, true)
#undef MINMAX
+#define BF16_MINMAX(name, ismin, isiee, ismag) \
+bfloat16 bfloat16_ ## name(bfloat16 a, bfloat16 b, float_status *s) \
+{ \
+ FloatParts pa = bfloat16_unpack_canonical(a, s); \
+ FloatParts pb = bfloat16_unpack_canonical(b, s); \
+ FloatParts pr = minmax_floats(pa, pb, ismin, isiee, ismag, s); \
+ \
+ return bfloat16_round_pack_canonical(pr, s); \
+}
+
+BF16_MINMAX(min, true, false, false)
+BF16_MINMAX(minnum, true, true, false)
+BF16_MINMAX(minnummag, true, true, true)
+BF16_MINMAX(max, false, false, false)
+BF16_MINMAX(maxnum, false, true, false)
+BF16_MINMAX(maxnummag, false, true, true)
+
+#undef BF16_MINMAX
+
/* Floating point compare */
static FloatRelation compare_floats(FloatParts a, FloatParts b, bool is_quiet,
float_status *s)
@@ -3008,6 +3118,24 @@ FloatRelation float64_compare_quiet(float64 a, float64 b, float_status *s)
return f64_compare(a, b, true, s);
}
+static int QEMU_FLATTEN
+soft_bf16_compare(bfloat16 a, bfloat16 b, bool is_quiet, float_status *s)
+{
+ FloatParts pa = bfloat16_unpack_canonical(a, s);
+ FloatParts pb = bfloat16_unpack_canonical(b, s);
+ return compare_floats(pa, pb, is_quiet, s);
+}
+
+int bfloat16_compare(bfloat16 a, bfloat16 b, float_status *s)
+{
+ return soft_bf16_compare(a, b, false, s);
+}
+
+int bfloat16_compare_quiet(bfloat16 a, bfloat16 b, float_status *s)
+{
+ return soft_bf16_compare(a, b, true, s);
+}
+
/* Multiply A by 2 raised to the power N. */
static FloatParts scalbn_decomposed(FloatParts a, int n, float_status *s)
{
@@ -3047,6 +3175,13 @@ float64 float64_scalbn(float64 a, int n, float_status *status)
return float64_round_pack_canonical(pr, status);
}
+bfloat16 bfloat16_scalbn(bfloat16 a, int n, float_status *status)
+{
+ FloatParts pa = bfloat16_unpack_canonical(a, status);
+ FloatParts pr = scalbn_decomposed(pa, n, status);
+ return bfloat16_round_pack_canonical(pr, status);
+}
+
/*
* Square Root
*
@@ -3197,6 +3332,13 @@ float64 QEMU_FLATTEN float64_sqrt(float64 xa, float_status *s)
return soft_f64_sqrt(ua.s, s);
}
+bfloat16 QEMU_FLATTEN bfloat16_sqrt(bfloat16 a, float_status *status)
+{
+ FloatParts pa = bfloat16_unpack_canonical(a, status);
+ FloatParts pr = sqrt_float(pa, status, &bfloat16_params);
+ return bfloat16_round_pack_canonical(pr, status);
+}
+
/*----------------------------------------------------------------------------
| The pattern for a default generated NaN.
*----------------------------------------------------------------------------*/
@@ -3239,6 +3381,13 @@ float128 float128_default_nan(float_status *status)
return r;
}
+bfloat16 bfloat16_default_nan(float_status *status)
+{
+ FloatParts p = parts_default_nan(status);
+ p.frac >>= bfloat16_params.frac_shift;
+ return bfloat16_pack_raw(p);
+}
+
/*----------------------------------------------------------------------------
| Returns a quiet NaN from a signalling NaN for the floating point value `a'.
*----------------------------------------------------------------------------*/
@@ -3270,6 +3419,14 @@ float64 float64_silence_nan(float64 a, float_status *status)
return float64_pack_raw(p);
}
+bfloat16 bfloat16_silence_nan(bfloat16 a, float_status *status)
+{
+ FloatParts p = bfloat16_unpack_raw(a);
+ p.frac <<= bfloat16_params.frac_shift;
+ p = parts_silence_nan(p, status);
+ p.frac >>= bfloat16_params.frac_shift;
+ return bfloat16_pack_raw(p);
+}
/*----------------------------------------------------------------------------
| If `a' is denormal and we are in flush-to-zero mode then set the
@@ -3319,6 +3476,17 @@ float64 float64_squash_input_denormal(float64 a, float_status *status)
return a;
}
+bfloat16 bfloat16_squash_input_denormal(bfloat16 a, float_status *status)
+{
+ if (status->flush_inputs_to_zero) {
+ FloatParts p = bfloat16_unpack_raw(a);
+ if (parts_squash_denormal(p, status)) {
+ return bfloat16_set_sign(bfloat16_zero, p.sign);
+ }
+ }
+ return a;
+}
+
/*----------------------------------------------------------------------------
| Takes a 64-bit fixed-point value `absZ' with binary point between bits 6
| and 7, and returns the properly rounded 32-bit integer corresponding to the
diff --git a/include/fpu/softfloat-types.h b/include/fpu/softfloat-types.h
index 7680193ebc..3a3bf55631 100644
--- a/include/fpu/softfloat-types.h
+++ b/include/fpu/softfloat-types.h
@@ -112,6 +112,11 @@ typedef struct {
#define make_float128(high_, low_) ((float128) { .high = high_, .low = low_ })
#define make_float128_init(high_, low_) { .high = high_, .low = low_ }
+/*
+ * Software neural-network floating-point types.
+ */
+typedef uint16_t bfloat16;
+
/*
* Software IEC/IEEE floating-point underflow tininess-detection mode.
*/
diff --git a/include/fpu/softfloat.h b/include/fpu/softfloat.h
index 659218b5c7..198f954e4d 100644
--- a/include/fpu/softfloat.h
+++ b/include/fpu/softfloat.h
@@ -239,6 +239,37 @@ bool float16_is_quiet_nan(float16, float_status *status);
bool float16_is_signaling_nan(float16, float_status *status);
float16 float16_silence_nan(float16, float_status *status);
+/*----------------------------------------------------------------------------
+| Software bfloat16 operations.
+*----------------------------------------------------------------------------*/
+
+bfloat16 bfloat16_add(bfloat16, bfloat16, float_status *status);
+bfloat16 bfloat16_sub(bfloat16, bfloat16, float_status *status);
+bfloat16 bfloat16_mul(bfloat16, bfloat16, float_status *status);
+bfloat16 bfloat16_div(bfloat16, bfloat16, float_status *status);
+bfloat16 bfloat16_muladd(bfloat16, bfloat16, bfloat16, int,
+ float_status *status);
+float16 bfloat16_scalbn(bfloat16, int, float_status *status);
+bfloat16 bfloat16_min(bfloat16, bfloat16, float_status *status);
+bfloat16 bfloat16_max(bfloat16, bfloat16, float_status *status);
+bfloat16 bfloat16_minnum(bfloat16, bfloat16, float_status *status);
+bfloat16 bfloat16_maxnum(bfloat16, bfloat16, float_status *status);
+bfloat16 bfloat16_minnummag(bfloat16, bfloat16, float_status *status);
+bfloat16 bfloat16_maxnummag(bfloat16, bfloat16, float_status *status);
+bfloat16 bfloat16_sqrt(bfloat16, float_status *status);
+int bfloat16_compare(bfloat16, bfloat16, float_status *status);
+int bfloat16_compare_quiet(bfloat16, bfloat16, float_status *status);
+int bfloat16_unordered_quiet(bfloat16, bfloat16, float_status *status);
+int bfloat16_le(bfloat16, bfloat16, float_status *status);
+int bfloat16_lt(bfloat16, bfloat16, float_status *status);
+int bfloat16_eq_quiet(bfloat16, bfloat16, float_status *status);
+
+int bfloat16_is_quiet_nan(bfloat16, float_status *status);
+int bfloat16_is_signaling_nan(bfloat16, float_status *status);
+bfloat16 bfloat16_silence_nan(bfloat16, float_status *status);
+bfloat16 bfloat16_default_nan(float_status *status);
+bfloat16 bfloat16_squash_input_denormal(bfloat16 a, float_status *status);
+
static inline bool float16_is_any_nan(float16 a)
{
return ((float16_val(a) & ~0x8000) > 0x7c00);
@@ -293,6 +324,19 @@ static inline float16 float16_set_sign(float16 a, int sign)
#define float16_three make_float16(0x4200)
#define float16_infinity make_float16(0x7c00)
+static inline bfloat16 bfloat16_set_sign(bfloat16 a, int sign)
+{
+ return (a & 0x7fff) | (sign << 15);
+}
+
+#define bfloat16_zero 0
+#define bfloat16_half 0x3f00
+#define bfloat16_one 0x3f80
+#define bfloat16_one_point_five 0x3fc0
+#define bfloat16_two 0x4000
+#define bfloat16_three 0x4040
+#define bfloat16_infinity 0x7f80
+
/*----------------------------------------------------------------------------
| The pattern for a default generated half-precision NaN.
*----------------------------------------------------------------------------*/
--
2.23.0
^ permalink raw reply related [flat|nested] 5+ messages in thread* [PATCH 2/3] fpu/softfloat: Define convert operations for bfloat16
2020-08-13 7:14 [PATCH 0/3] Implement blfoat16 in softfloat LIU Zhiwei
2020-08-13 7:14 ` [PATCH 1/3] fpu/softfloat: Define operations for bfloat16 LIU Zhiwei
@ 2020-08-13 7:14 ` LIU Zhiwei
2020-08-13 7:14 ` [PATCH 3/3] fpu/softfloat: Define misc " LIU Zhiwei
2020-08-13 16:06 ` [PATCH 0/3] Implement blfoat16 in softfloat Richard Henderson
3 siblings, 0 replies; 5+ messages in thread
From: LIU Zhiwei @ 2020-08-13 7:14 UTC (permalink / raw)
To: qemu-devel
Cc: alex.bennee, richard.henderson, LIU Zhiwei, aurelien,
peter.maydell
Signed-off-by: LIU Zhiwei <zhiwei_liu@c-sky.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
---
fpu/softfloat.c | 223 ++++++++++++++++++++++++++++++++++++++++
include/fpu/softfloat.h | 48 +++++++++
2 files changed, 271 insertions(+)
diff --git a/fpu/softfloat.c b/fpu/softfloat.c
index d4205f92d5..afb121135d 100644
--- a/fpu/softfloat.c
+++ b/fpu/softfloat.c
@@ -2014,6 +2014,34 @@ float32 float64_to_float32(float64 a, float_status *s)
return float32_round_pack_canonical(pr, s);
}
+float32 bfloat16_to_float32(bfloat16 a, float_status *s)
+{
+ FloatParts p = bfloat16_unpack_canonical(a, s);
+ FloatParts pr = float_to_float(p, &float32_params, s);
+ return float32_round_pack_canonical(pr, s);
+}
+
+float64 bfloat16_to_float64(bfloat16 a, float_status *s)
+{
+ FloatParts p = bfloat16_unpack_canonical(a, s);
+ FloatParts pr = float_to_float(p, &float64_params, s);
+ return float64_round_pack_canonical(pr, s);
+}
+
+bfloat16 float32_to_bfloat16(float32 a, float_status *s)
+{
+ FloatParts p = float32_unpack_canonical(a, s);
+ FloatParts pr = float_to_float(p, &bfloat16_params, s);
+ return bfloat16_round_pack_canonical(pr, s);
+}
+
+bfloat16 float64_to_bfloat16(float64 a, float_status *s)
+{
+ FloatParts p = float64_unpack_canonical(a, s);
+ FloatParts pr = float_to_float(p, &bfloat16_params, s);
+ return bfloat16_round_pack_canonical(pr, s);
+}
+
/*
* Rounds the floating-point value `a' to an integer, and returns the
* result as a floating-point value. The operation is performed
@@ -2143,6 +2171,18 @@ float64 float64_round_to_int(float64 a, float_status *s)
return float64_round_pack_canonical(pr, s);
}
+/*
+ * Rounds the bfloat16 value `a' to an integer, and returns the
+ * result as a bfloat16 value.
+ */
+
+bfloat16 bfloat16_round_to_int(bfloat16 a, float_status *s)
+{
+ FloatParts pa = bfloat16_unpack_canonical(a, s);
+ FloatParts pr = round_to_int(pa, s->float_rounding_mode, 0, s);
+ return bfloat16_round_pack_canonical(pr, s);
+}
+
/*
* Returns the result of converting the floating-point value `a' to
* the two's complement integer format. The conversion is performed
@@ -2353,6 +2393,62 @@ int64_t float64_to_int64_round_to_zero(float64 a, float_status *s)
return float64_to_int64_scalbn(a, float_round_to_zero, 0, s);
}
+/*
+ * Returns the result of converting the floating-point value `a' to
+ * the two's complement integer format.
+ */
+
+int16_t bfloat16_to_int16_scalbn(bfloat16 a, int rmode, int scale,
+ float_status *s)
+{
+ return round_to_int_and_pack(bfloat16_unpack_canonical(a, s),
+ rmode, scale, INT16_MIN, INT16_MAX, s);
+}
+
+int32_t bfloat16_to_int32_scalbn(bfloat16 a, int rmode, int scale,
+ float_status *s)
+{
+ return round_to_int_and_pack(bfloat16_unpack_canonical(a, s),
+ rmode, scale, INT32_MIN, INT32_MAX, s);
+}
+
+int64_t bfloat16_to_int64_scalbn(bfloat16 a, int rmode, int scale,
+ float_status *s)
+{
+ return round_to_int_and_pack(bfloat16_unpack_canonical(a, s),
+ rmode, scale, INT64_MIN, INT64_MAX, s);
+}
+
+int16_t bfloat16_to_int16(bfloat16 a, float_status *s)
+{
+ return bfloat16_to_int16_scalbn(a, s->float_rounding_mode, 0, s);
+}
+
+int32_t bfloat16_to_int32(bfloat16 a, float_status *s)
+{
+ return bfloat16_to_int32_scalbn(a, s->float_rounding_mode, 0, s);
+}
+
+int64_t bfloat16_to_int64(bfloat16 a, float_status *s)
+{
+ return bfloat16_to_int64_scalbn(a, s->float_rounding_mode, 0, s);
+}
+
+int16_t bfloat16_to_int16_round_to_zero(bfloat16 a, float_status *s)
+{
+ return bfloat16_to_int16_scalbn(a, float_round_to_zero, 0, s);
+}
+
+int32_t bfloat16_to_int32_round_to_zero(bfloat16 a, float_status *s)
+{
+ return bfloat16_to_int32_scalbn(a, float_round_to_zero, 0, s);
+}
+
+int64_t bfloat16_to_int64_round_to_zero(bfloat16 a, float_status *s)
+{
+ return bfloat16_to_int64_scalbn(a, float_round_to_zero, 0, s);
+}
+
/*
* Returns the result of converting the floating-point value `a' to
* the unsigned integer format. The conversion is performed according
@@ -2566,6 +2662,62 @@ uint64_t float64_to_uint64_round_to_zero(float64 a, float_status *s)
return float64_to_uint64_scalbn(a, float_round_to_zero, 0, s);
}
+/*
+ * Returns the result of converting the bfloat16 value `a' to
+ * the unsigned integer format.
+ */
+
+uint16_t bfloat16_to_uint16_scalbn(bfloat16 a, int rmode, int scale,
+ float_status *s)
+{
+ return round_to_uint_and_pack(bfloat16_unpack_canonical(a, s),
+ rmode, scale, UINT16_MAX, s);
+}
+
+uint32_t bfloat16_to_uint32_scalbn(bfloat16 a, int rmode, int scale,
+ float_status *s)
+{
+ return round_to_uint_and_pack(bfloat16_unpack_canonical(a, s),
+ rmode, scale, UINT32_MAX, s);
+}
+
+uint64_t bfloat16_to_uint64_scalbn(bfloat16 a, int rmode, int scale,
+ float_status *s)
+{
+ return round_to_uint_and_pack(bfloat16_unpack_canonical(a, s),
+ rmode, scale, UINT64_MAX, s);
+}
+
+uint16_t bfloat16_to_uint16(bfloat16 a, float_status *s)
+{
+ return bfloat16_to_uint16_scalbn(a, s->float_rounding_mode, 0, s);
+}
+
+uint32_t bfloat16_to_uint32(bfloat16 a, float_status *s)
+{
+ return bfloat16_to_uint32_scalbn(a, s->float_rounding_mode, 0, s);
+}
+
+uint64_t bfloat16_to_uint64(bfloat16 a, float_status *s)
+{
+ return bfloat16_to_uint64_scalbn(a, s->float_rounding_mode, 0, s);
+}
+
+uint16_t bfloat16_to_uint16_round_to_zero(bfloat16 a, float_status *s)
+{
+ return bfloat16_to_uint16_scalbn(a, float_round_to_zero, 0, s);
+}
+
+uint32_t bfloat16_to_uint32_round_to_zero(bfloat16 a, float_status *s)
+{
+ return bfloat16_to_uint32_scalbn(a, float_round_to_zero, 0, s);
+}
+
+uint64_t bfloat16_to_uint64_round_to_zero(bfloat16 a, float_status *s)
+{
+ return bfloat16_to_uint64_scalbn(a, float_round_to_zero, 0, s);
+}
+
/*
* Integer to float conversions
*
@@ -2692,6 +2844,41 @@ float64 int16_to_float64(int16_t a, float_status *status)
return int64_to_float64_scalbn(a, 0, status);
}
+/*
+ * Returns the result of converting the two's complement integer `a'
+ * to the bfloat16 format.
+ */
+
+bfloat16 int64_to_bfloat16_scalbn(int64_t a, int scale, float_status *status)
+{
+ FloatParts pa = int_to_float(a, scale, status);
+ return bfloat16_round_pack_canonical(pa, status);
+}
+
+bfloat16 int32_to_bfloat16_scalbn(int32_t a, int scale, float_status *status)
+{
+ return int64_to_bfloat16_scalbn(a, scale, status);
+}
+
+bfloat16 int16_to_bfloat16_scalbn(int16_t a, int scale, float_status *status)
+{
+ return int64_to_bfloat16_scalbn(a, scale, status);
+}
+
+bfloat16 int64_to_bfloat16(int64_t a, float_status *status)
+{
+ return int64_to_bfloat16_scalbn(a, 0, status);
+}
+
+bfloat16 int32_to_bfloat16(int32_t a, float_status *status)
+{
+ return int64_to_bfloat16_scalbn(a, 0, status);
+}
+
+bfloat16 int16_to_bfloat16(int16_t a, float_status *status)
+{
+ return int64_to_bfloat16_scalbn(a, 0, status);
+}
/*
* Unsigned Integer to float conversions
@@ -2817,6 +3004,42 @@ float64 uint16_to_float64(uint16_t a, float_status *status)
return uint64_to_float64_scalbn(a, 0, status);
}
+/*
+ * Returns the result of converting the unsigned integer `a' to the
+ * bfloat16 format.
+ */
+
+bfloat16 uint64_to_bfloat16_scalbn(uint64_t a, int scale, float_status *status)
+{
+ FloatParts pa = uint_to_float(a, scale, status);
+ return bfloat16_round_pack_canonical(pa, status);
+}
+
+bfloat16 uint32_to_bfloat16_scalbn(uint32_t a, int scale, float_status *status)
+{
+ return uint64_to_bfloat16_scalbn(a, scale, status);
+}
+
+bfloat16 uint16_to_bfloat16_scalbn(uint16_t a, int scale, float_status *status)
+{
+ return uint64_to_bfloat16_scalbn(a, scale, status);
+}
+
+bfloat16 uint64_to_bfloat16(uint64_t a, float_status *status)
+{
+ return uint64_to_bfloat16_scalbn(a, 0, status);
+}
+
+bfloat16 uint32_to_bfloat16(uint32_t a, float_status *status)
+{
+ return uint64_to_bfloat16_scalbn(a, 0, status);
+}
+
+bfloat16 uint16_to_bfloat16(uint16_t a, float_status *status)
+{
+ return uint64_to_bfloat16_scalbn(a, 0, status);
+}
+
/* Float Min/Max */
/* min() and max() functions. These can't be implemented as
* 'compare and pick one input' because that would mishandle
diff --git a/include/fpu/softfloat.h b/include/fpu/softfloat.h
index 198f954e4d..4f72665b02 100644
--- a/include/fpu/softfloat.h
+++ b/include/fpu/softfloat.h
@@ -270,6 +270,54 @@ bfloat16 bfloat16_silence_nan(bfloat16, float_status *status);
bfloat16 bfloat16_default_nan(float_status *status);
bfloat16 bfloat16_squash_input_denormal(bfloat16 a, float_status *status);
+/*----------------------------------------------------------------------------
+| Software bfloat16 conversion routines.
+*----------------------------------------------------------------------------*/
+
+bfloat16 bfloat16_round_to_int(bfloat16, float_status *status);
+bfloat16 float32_to_bfloat16(float32, float_status *status);
+float32 bfloat16_to_float32(bfloat16, float_status *status);
+bfloat16 float64_to_bfloat16(float64 a, float_status *status);
+float64 bfloat16_to_float64(bfloat16 a, float_status *status);
+
+int16_t bfloat16_to_int16_scalbn(bfloat16, int, int, float_status *status);
+int32_t bfloat16_to_int32_scalbn(bfloat16, int, int, float_status *status);
+int64_t bfloat16_to_int64_scalbn(bfloat16, int, int, float_status *status);
+
+int16_t bfloat16_to_int16(bfloat16, float_status *status);
+int32_t bfloat16_to_int32(bfloat16, float_status *status);
+int64_t bfloat16_to_int64(bfloat16, float_status *status);
+
+int16_t bfloat16_to_int16_round_to_zero(bfloat16, float_status *status);
+int32_t bfloat16_to_int32_round_to_zero(bfloat16, float_status *status);
+int64_t bfloat16_to_int64_round_to_zero(bfloat16, float_status *status);
+
+uint16_t bfloat16_to_uint16_scalbn(bfloat16 a, int, int, float_status *status);
+uint32_t bfloat16_to_uint32_scalbn(bfloat16 a, int, int, float_status *status);
+uint64_t bfloat16_to_uint64_scalbn(bfloat16 a, int, int, float_status *status);
+
+uint16_t bfloat16_to_uint16(bfloat16 a, float_status *status);
+uint32_t bfloat16_to_uint32(bfloat16 a, float_status *status);
+uint64_t bfloat16_to_uint64(bfloat16 a, float_status *status);
+
+uint16_t bfloat16_to_uint16_round_to_zero(bfloat16 a, float_status *status);
+uint32_t bfloat16_to_uint32_round_to_zero(bfloat16 a, float_status *status);
+uint64_t bfloat16_to_uint64_round_to_zero(bfloat16 a, float_status *status);
+
+bfloat16 int16_to_bfloat16_scalbn(int16_t a, int, float_status *status);
+bfloat16 int32_to_bfloat16_scalbn(int32_t a, int, float_status *status);
+bfloat16 int64_to_bfloat16_scalbn(int64_t a, int, float_status *status);
+bfloat16 uint16_to_bfloat16_scalbn(uint16_t a, int, float_status *status);
+bfloat16 uint32_to_bfloat16_scalbn(uint32_t a, int, float_status *status);
+bfloat16 uint64_to_bfloat16_scalbn(uint64_t a, int, float_status *status);
+
+bfloat16 int16_to_bfloat16(int16_t a, float_status *status);
+bfloat16 int32_to_bfloat16(int32_t a, float_status *status);
+bfloat16 int64_to_bfloat16(int64_t a, float_status *status);
+bfloat16 uint16_to_bfloat16(uint16_t a, float_status *status);
+bfloat16 uint32_to_bfloat16(uint32_t a, float_status *status);
+bfloat16 uint64_to_bfloat16(uint64_t a, float_status *status);
+
static inline bool float16_is_any_nan(float16 a)
{
return ((float16_val(a) & ~0x8000) > 0x7c00);
--
2.23.0
^ permalink raw reply related [flat|nested] 5+ messages in thread* [PATCH 3/3] fpu/softfloat: Define misc operations for bfloat16
2020-08-13 7:14 [PATCH 0/3] Implement blfoat16 in softfloat LIU Zhiwei
2020-08-13 7:14 ` [PATCH 1/3] fpu/softfloat: Define operations for bfloat16 LIU Zhiwei
2020-08-13 7:14 ` [PATCH 2/3] fpu/softfloat: Define convert " LIU Zhiwei
@ 2020-08-13 7:14 ` LIU Zhiwei
2020-08-13 16:06 ` [PATCH 0/3] Implement blfoat16 in softfloat Richard Henderson
3 siblings, 0 replies; 5+ messages in thread
From: LIU Zhiwei @ 2020-08-13 7:14 UTC (permalink / raw)
To: qemu-devel
Cc: alex.bennee, richard.henderson, LIU Zhiwei, aurelien,
peter.maydell
Signed-off-by: LIU Zhiwei <zhiwei_liu@c-sky.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
---
fpu/softfloat-specialize.inc.c | 38 +++++++++++++++++++++++++++++++
include/fpu/softfloat.h | 41 ++++++++++++++++++++++++++++++++++
2 files changed, 79 insertions(+)
diff --git a/fpu/softfloat-specialize.inc.c b/fpu/softfloat-specialize.inc.c
index 034d18199c..1b6c4e47f8 100644
--- a/fpu/softfloat-specialize.inc.c
+++ b/fpu/softfloat-specialize.inc.c
@@ -259,6 +259,25 @@ bool float16_is_quiet_nan(float16 a_, float_status *status)
#endif
}
+/*----------------------------------------------------------------------------
+| Returns 1 if the bfloat16 value `a' is a quiet
+| NaN; otherwise returns 0.
+*----------------------------------------------------------------------------*/
+
+int bfloat16_is_quiet_nan(bfloat16 a_, float_status *status)
+{
+#ifdef NO_SIGNALING_NANS
+ return bfloat16_is_any_nan(a_);
+#else
+ uint16_t a = a_;
+ if (snan_bit_is_one(status)) {
+ return (((a >> 6) & 0x1FF) == 0x1FE) && (a & 0x3F);
+ } else {
+ return ((a >> 6) & 0x1FF) == 0x1FF;
+ }
+#endif
+}
+
/*----------------------------------------------------------------------------
| Returns 1 if the half-precision floating-point value `a' is a signaling
| NaN; otherwise returns 0.
@@ -278,6 +297,25 @@ bool float16_is_signaling_nan(float16 a_, float_status *status)
#endif
}
+/*----------------------------------------------------------------------------
+| Returns 1 if the bfloat16 value `a' is a signaling
+| NaN; otherwise returns 0.
+*----------------------------------------------------------------------------*/
+
+int bfloat16_is_signaling_nan(bfloat16 a_, float_status *status)
+{
+#ifdef NO_SIGNALING_NANS
+ return 0;
+#else
+ uint16_t a = a_;
+ if (snan_bit_is_one(status)) {
+ return ((a >> 6) & 0x1FF) == 0x1FF;
+ } else {
+ return (((a >> 6) & 0x1FF) == 0x1FE) && (a & 0x3F);
+ }
+#endif
+}
+
/*----------------------------------------------------------------------------
| Returns 1 if the single-precision floating-point value `a' is a quiet
| NaN; otherwise returns 0.
diff --git a/include/fpu/softfloat.h b/include/fpu/softfloat.h
index 4f72665b02..d7ce3e3483 100644
--- a/include/fpu/softfloat.h
+++ b/include/fpu/softfloat.h
@@ -372,6 +372,47 @@ static inline float16 float16_set_sign(float16 a, int sign)
#define float16_three make_float16(0x4200)
#define float16_infinity make_float16(0x7c00)
+static inline int bfloat16_is_any_nan(bfloat16 a)
+{
+ return ((a & ~0x8000) > 0x7F80);
+}
+
+static inline int bfloat16_is_neg(bfloat16 a)
+{
+ return a >> 15;
+}
+
+static inline int bfloat16_is_infinity(bfloat16 a)
+{
+ return (a & 0x7fff) == 0x7F80;
+}
+
+static inline int bfloat16_is_zero(bfloat16 a)
+{
+ return (a & 0x7fff) == 0;
+}
+
+static inline int bfloat16_is_zero_or_denormal(bfloat16 a)
+{
+ return (a & 0x7F80) == 0;
+}
+
+static inline bfloat16 bfloat16_abs(bfloat16 a)
+{
+ /* Note that abs does *not* handle NaN specially, nor does
+ * it flush denormal inputs to zero.
+ */
+ return a & 0x7fff;
+}
+
+static inline bfloat16 bfloat16_chs(bfloat16 a)
+{
+ /* Note that chs does *not* handle NaN specially, nor does
+ * it flush denormal inputs to zero.
+ */
+ return a ^ 0x8000;
+}
+
static inline bfloat16 bfloat16_set_sign(bfloat16 a, int sign)
{
return (a & 0x7fff) | (sign << 15);
--
2.23.0
^ permalink raw reply related [flat|nested] 5+ messages in thread* Re: [PATCH 0/3] Implement blfoat16 in softfloat
2020-08-13 7:14 [PATCH 0/3] Implement blfoat16 in softfloat LIU Zhiwei
` (2 preceding siblings ...)
2020-08-13 7:14 ` [PATCH 3/3] fpu/softfloat: Define misc " LIU Zhiwei
@ 2020-08-13 16:06 ` Richard Henderson
3 siblings, 0 replies; 5+ messages in thread
From: Richard Henderson @ 2020-08-13 16:06 UTC (permalink / raw)
To: LIU Zhiwei, qemu-devel; +Cc: peter.maydell, alex.bennee, aurelien
On 8/13/20 12:14 AM, LIU Zhiwei wrote:
> As bfloat16 is more and more popular in many archs, implement bfloat16
> interfaces in softfloat, so that archs can add their bfloat16 insns
> based on the blfoat16 interfaces here.
>
> These interfaces have been tested by RISU on RISC-V bfloat16 with
> XuanTie C906.
>
> LIU Zhiwei (3):
> fpu/softfloat: Define operations for bfloat16
> fpu/softfloat: Define convert operations for bfloat16
> fpu/softfloat: Define misc operations for bfloat16
>
> fpu/softfloat-specialize.inc.c | 38 ++++
> fpu/softfloat.c | 391 +++++++++++++++++++++++++++++++++
> include/fpu/softfloat-types.h | 5 +
> include/fpu/softfloat.h | 133 +++++++++++
> 4 files changed, 567 insertions(+)
>
Thanks. Queued to softfloat-next.
r~
^ permalink raw reply [flat|nested] 5+ messages in thread