We can now add float16_mul and use the common decompose and
canonicalize functions to have a single implementation for
float16/32/64 versions.
Signed-off-by: Alex Bennée <alex.ben...@linaro.org>
---
fpu/softfloat.c | 207 ++++++++++++++++++------------------------------
include/fpu/softfloat.h | 1 +
2 files changed, 80 insertions(+), 128 deletions(-)
diff --git a/fpu/softfloat.c b/fpu/softfloat.c
index f89e47e3ef..6e9d4c172c 100644
--- a/fpu/softfloat.c
+++ b/fpu/softfloat.c
@@ -730,6 +730,85 @@ float64 float64_sub(float64 a, float64 b, float_status
*status)
return float64_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
+ * for Binary Floating-Point Arithmetic.
+ */
+
+static decomposed_parts mul_decomposed(decomposed_parts a, decomposed_parts b,
+ float_status *s)
+{
+ bool sign = a.sign ^ b.sign;
+
+ if (a.cls == float_class_normal && b.cls == float_class_normal) {
+ uint64_t hi, lo;
+ int exp = a.exp + b.exp;
+
+ mul64To128(a.frac, b.frac, &hi, &lo);
+ shift128RightJamming(hi, lo, DECOMPOSED_BINARY_POINT, &hi, &lo);
+ if (lo & DECOMPOSED_OVERFLOW_BIT) {
+ shift64RightJamming(lo, 1, &lo);
+ exp += 1;
+ }
+
+ /* Re-use a */
+ a.exp = exp;
+ a.sign = sign;
+ a.frac = lo;
+ return a;
+ }
+ /* handle all the NaN cases */
+ if (a.cls >= float_class_qnan || b.cls >= float_class_qnan) {
+ return pick_nan_parts(a, b, s);
+ }
+ /* Inf * Zero == NaN */
+ if (((1 << a.cls) | (1 << b.cls)) ==
+ ((1 << float_class_inf) | (1 << float_class_zero))) {
+ s->float_exception_flags |= float_flag_invalid;
+ a.cls = float_class_dnan;
+ a.sign = sign;
+ return a;
+ }
+ /* Multiply by 0 or Inf */
+ if (a.cls == float_class_inf || a.cls == float_class_zero) {
+ a.sign = sign;
+ return a;
+ }
+ if (b.cls == float_class_inf || b.cls == float_class_zero) {
+ b.sign = sign;
+ return b;
+ }
+ g_assert_not_reached();
+}
+
+float16 float16_mul(float16 a, float16 b, float_status *status)
+{
+ decomposed_parts pa = float16_unpack_canonical(a, status);
+ decomposed_parts pb = float16_unpack_canonical(b, status);
+ decomposed_parts pr = mul_decomposed(pa, pb, status);
+
+ return float16_round_pack_canonical(pr, status);
+}
+
+float32 float32_mul(float32 a, float32 b, float_status *status)
+{
+ decomposed_parts pa = float32_unpack_canonical(a, status);
+ decomposed_parts pb = float32_unpack_canonical(b, status);
+ decomposed_parts pr = mul_decomposed(pa, pb, status);
+
+ return float32_round_pack_canonical(pr, status);
+}
+
+float64 float64_mul(float64 a, float64 b, float_status *status)
+{
+ decomposed_parts pa = float64_unpack_canonical(a, status);
+ decomposed_parts pb = float64_unpack_canonical(b, status);
+ decomposed_parts pr = mul_decomposed(pa, pb, status);
+
+ return float64_round_pack_canonical(pr, status);
+}
+
/*----------------------------------------------------------------------------
| 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
@@ -2542,70 +2621,6 @@ float32 float32_round_to_int(float32 a, float_status
*status)
}
-/*----------------------------------------------------------------------------
-| Returns the result of multiplying the single-precision floating-point values
-| `a' and `b'. The operation is performed according to the IEC/IEEE Standard
-| for Binary Floating-Point Arithmetic.
-*----------------------------------------------------------------------------*/
-
-float32 float32_mul(float32 a, float32 b, float_status *status)
-{
- flag aSign, bSign, zSign;
- int aExp, bExp, zExp;
- uint32_t aSig, bSig;
- uint64_t zSig64;
- uint32_t zSig;
-
- a = float32_squash_input_denormal(a, status);
- b = float32_squash_input_denormal(b, status);
-
- aSig = extractFloat32Frac( a );
- aExp = extractFloat32Exp( a );
- aSign = extractFloat32Sign( a );
- bSig = extractFloat32Frac( b );
- bExp = extractFloat32Exp( b );
- bSign = extractFloat32Sign( b );
- zSign = aSign ^ bSign;
- if ( aExp == 0xFF ) {
- if ( aSig || ( ( bExp == 0xFF ) && bSig ) ) {
- return propagateFloat32NaN(a, b, status);
- }
- if ( ( bExp | bSig ) == 0 ) {
- float_raise(float_flag_invalid, status);
- return float32_default_nan(status);
- }
- return packFloat32( zSign, 0xFF, 0 );
- }
- if ( bExp == 0xFF ) {
- if (bSig) {
- return propagateFloat32NaN(a, b, status);
- }
- if ( ( aExp | aSig ) == 0 ) {
- float_raise(float_flag_invalid, status);
- return float32_default_nan(status);
- }
- return packFloat32( zSign, 0xFF, 0 );
- }
- if ( aExp == 0 ) {
- if ( aSig == 0 ) return packFloat32( zSign, 0, 0 );
- normalizeFloat32Subnormal( aSig, &aExp, &aSig );
- }
- if ( bExp == 0 ) {
- if ( bSig == 0 ) return packFloat32( zSign, 0, 0 );
- normalizeFloat32Subnormal( bSig, &bExp, &bSig );
- }
- zExp = aExp + bExp - 0x7F;
- aSig = ( aSig | 0x00800000 )<<7;
- bSig = ( bSig | 0x00800000 )<<8;
- shift64RightJamming( ( (uint64_t) aSig ) * bSig, 32, &zSig64 );
- zSig = zSig64;
- if ( 0 <= (int32_t) ( zSig<<1 ) ) {
- zSig <<= 1;
- --zExp;
- }
- return roundAndPackFloat32(zSign, zExp, zSig, status);
-
-}
/*----------------------------------------------------------------------------
| Returns the result of dividing the single-precision floating-point value `a'
@@ -4138,70 +4153,6 @@ float64 float64_trunc_to_int(float64 a, float_status
*status)
return res;
}
-
-/*----------------------------------------------------------------------------
-| Returns the result of multiplying the double-precision floating-point values
-| `a' and `b'. The operation is performed according to the IEC/IEEE Standard
-| for Binary Floating-Point Arithmetic.
-*----------------------------------------------------------------------------*/
-
-float64 float64_mul(float64 a, float64 b, float_status *status)
-{
- flag aSign, bSign, zSign;
- int aExp, bExp, zExp;
- uint64_t aSig, bSig, zSig0, zSig1;
-
- a = float64_squash_input_denormal(a, status);
- b = float64_squash_input_denormal(b, status);
-
- aSig = extractFloat64Frac( a );
- aExp = extractFloat64Exp( a );
- aSign = extractFloat64Sign( a );
- bSig = extractFloat64Frac( b );
- bExp = extractFloat64Exp( b );
- bSign = extractFloat64Sign( b );
- zSign = aSign ^ bSign;
- if ( aExp == 0x7FF ) {
- if ( aSig || ( ( bExp == 0x7FF ) && bSig ) ) {
- return propagateFloat64NaN(a, b, status);
- }
- if ( ( bExp | bSig ) == 0 ) {
- float_raise(float_flag_invalid, status);
- return float64_default_nan(status);
- }
- return packFloat64( zSign, 0x7FF, 0 );
- }
- if ( bExp == 0x7FF ) {
- if (bSig) {
- return propagateFloat64NaN(a, b, status);
- }
- if ( ( aExp | aSig ) == 0 ) {
- float_raise(float_flag_invalid, status);
- return float64_default_nan(status);
- }
- return packFloat64( zSign, 0x7FF, 0 );
- }
- if ( aExp == 0 ) {
- if ( aSig == 0 ) return packFloat64( zSign, 0, 0 );
- normalizeFloat64Subnormal( aSig, &aExp, &aSig );
- }
- if ( bExp == 0 ) {
- if ( bSig == 0 ) return packFloat64( zSign, 0, 0 );
- normalizeFloat64Subnormal( bSig, &bExp, &bSig );
- }
- zExp = aExp + bExp - 0x3FF;
- aSig = ( aSig | LIT64( 0x0010000000000000 ) )<<10;
- bSig = ( bSig | LIT64( 0x0010000000000000 ) )<<11;
- mul64To128( aSig, bSig, &zSig0, &zSig1 );
- zSig0 |= ( zSig1 != 0 );
- if ( 0 <= (int64_t) ( zSig0<<1 ) ) {
- zSig0 <<= 1;
- --zExp;
- }
- return roundAndPackFloat64(zSign, zExp, zSig0, status);
-
-}
-
/*----------------------------------------------------------------------------
| Returns the result of dividing the double-precision floating-point value `a'
| by the corresponding value `b'. The operation is performed according to
diff --git a/include/fpu/softfloat.h b/include/fpu/softfloat.h
index 3238916aba..1fe8734261 100644
--- a/include/fpu/softfloat.h
+++ b/include/fpu/softfloat.h
@@ -348,6 +348,7 @@ float64 float16_to_float64(float16 a, flag ieee,
float_status *status);
float16 float16_add(float16, float16, float_status *status);
float16 float16_sub(float16, float16, float_status *status);
+float16 float16_mul(float16, float16, float_status *status);
int float16_is_quiet_nan(float16, float_status *status);
int float16_is_signaling_nan(float16, float_status *status);
--
2.15.1
