WebSVN – HelenOS-historic – Diff – /uspace/trunk/softfloat/generic/mul.c

     __u64 mant1, mant2;
     __s32 exp;
     result.parts.sign = a.parts.sign ^ b.parts.sign;
-    if ((isFloat32NaN(a))||(isFloat32NaN(b))) {
+    if (isFloat32NaN(a) || isFloat32NaN(b) ) {
         /* TODO: fix SigNaNs */
         if (isFloat32SigNaN(a)) {
             result.parts.mantisa = a.parts.mantisa;
             result.parts.exp = a.parts.exp;
             return result;
             result.parts.mantisa = b.parts.mantisa;
             result.parts.exp = b.parts.exp;
             return result;
         };
         /* set NaN as result */
-        result.parts.mantisa = 0x1;
-        result.parts.exp = 0xFF;
+        result.binary = FLOAT32_NAN;
         return result;
     };
     if (isFloat32Infinity(a)) {
         if (isFloat32Zero(b)) {
             /* FIXME: zero * infinity */
-            result.parts.mantisa = 0x1;
-            result.parts.exp = 0xFF;
+            result.binary = FLOAT32_NAN;
             return result;
+        }
         result.parts.mantisa = a.parts.mantisa;
         result.parts.exp = a.parts.exp;
         return result;
+    }
     if (isFloat32Infinity(b)) {
         if (isFloat32Zero(a)) {
             /* FIXME: zero * infinity */
-            result.parts.mantisa = 0x1;
-            result.parts.exp = 0xFF;
+            result.binary = FLOAT32_NAN;
             return result;
+        }
         result.parts.mantisa = b.parts.mantisa;
         result.parts.exp = b.parts.exp;
         return result;
     /* exp is signed so we can easy detect underflow */
     exp = a.parts.exp + b.parts.exp;
     exp -= FLOAT32_BIAS;
-    if (exp >= 0xFF ) {
+    if (exp >= FLOAT32_MAX_EXPONENT) {
         /* FIXME: overflow */
         /* set infinity as result */
-        result.parts.mantisa = 0x0;
+        result.binary = FLOAT32_INF;
-        result.parts.exp = 0xFF;
+        result.parts.sign = a.parts.sign ^ b.parts.sign;
         return result;
     };
     if (exp < 0) {
         /* FIXME: underflow */
         result.parts.exp = 0x0;
         return result;
     };
     mant1 = a.parts.mantisa;
-    if (a.parts.exp>0) {
+    if (a.parts.exp > 0) {
-        mant1 |= 0x800000;
+        mant1 |= FLOAT32_HIDDEN_BIT_MASK;
     } else {
         ++exp;
     };
     mant2 = b.parts.mantisa;
-    if (b.parts.exp>0) {
+    if (b.parts.exp > 0) {
-        mant2 |= 0x800000;
+        mant2 |= FLOAT32_HIDDEN_BIT_MASK;
     } else {
         ++exp;
     };
     mant1 <<= 1; /* one bit space for rounding */
     mant1 = mant1 * mant2;
 /* round and return */
-    while ((exp < 0xFF )&&(mant1 > 0x1FFFFFF )) {
+    while ((exp < FLOAT32_MAX_EXPONENT) && (mant1 >= ( 1 << (FLOAT32_MANTISA_SIZE + 2)))) {
-        /* 0xFFFFFF is 23 bits of mantisa + one more for hidden bit (all shifted 1 bit left)*/
+        /* 23 bits of mantisa + one more for hidden bit (all shifted 1 bit left)*/
         ++exp;
         mant1 >>= 1;
     };
     /* rounding */
     //++mant1; /* FIXME: not works - without it is ok */
     mant1 >>= 1; /* shift off rounding space */
-    if ((exp < 0xFF )&&(mant1 > 0xFFFFFF )) {
+    if ((exp < FLOAT32_MAX_EXPONENT) && (mant1 >= (1 << (FLOAT32_MANTISA_SIZE + 1)))) {
         ++exp;
         mant1 >>= 1;
     };
-    if (exp >= 0xFF ) {
+    if (exp >= FLOAT32_MAX_EXPONENT ) {
         /* TODO: fix overflow */
         /* return infinity*/
-        result.parts.exp = 0xFF;
+        result.parts.exp = FLOAT32_MAX_EXPONENT;
         result.parts.mantisa = 0x0;
         return result;
+    }
     exp -= FLOAT32_MANTISA_SIZE;
         result.parts.mantisa = 0;
         return result;
         };
     };
     result.parts.exp = exp;
+    result.parts.mantisa = mant1 & ( (1 << FLOAT32_MANTISA_SIZE) - 1);
+    return result;
+}
+/** Multiply two 64 bit float numbers
+ *
+ */
+float64 mulFloat64(float64 a, float64 b)
+{
+    float64 result;
+    __u64 mant1, mant2;
+    __s32 exp;
+    result.parts.sign = a.parts.sign ^ b.parts.sign;
+    if (isFloat64NaN(a) || isFloat64NaN(b) ) {
+        /* TODO: fix SigNaNs */
+        if (isFloat64SigNaN(a)) {
+            result.parts.mantisa = a.parts.mantisa;
+            result.parts.exp = a.parts.exp;
+            return result;
+        };
+        if (isFloat64SigNaN(b)) { /* TODO: fix SigNaN */
+            result.parts.mantisa = b.parts.mantisa;
+            result.parts.exp = b.parts.exp;
+            return result;
+        };
+        /* set NaN as result */
+        result.binary = FLOAT64_NAN;
+        return result;
+    };
+    if (isFloat64Infinity(a)) {
+        if (isFloat64Zero(b)) {
+            /* FIXME: zero * infinity */
+            result.binary = FLOAT64_NAN;
+            return result;
+        }
-    result.parts.mantisa = mant1 & 0x7FFFFF;
+        result.parts.mantisa = a.parts.mantisa;
+        result.parts.exp = a.parts.exp;
+        return result;
+    }
+    if (isFloat64Infinity(b)) {
+        if (isFloat64Zero(a)) {
+            /* FIXME: zero * infinity */
+            result.binary = FLOAT64_NAN;
+            return result;
+        }
+        result.parts.mantisa = b.parts.mantisa;
+        result.parts.exp = b.parts.exp;
+        return result;
+    }
+    /* exp is signed so we can easy detect underflow */
+    exp = a.parts.exp + b.parts.exp;
+    exp -= FLOAT64_BIAS;
+    if (exp >= FLOAT64_MAX_EXPONENT) {
+        /* FIXME: overflow */
+        /* set infinity as result */
+        result.binary = FLOAT64_INF;
+        result.parts.sign = a.parts.sign ^ b.parts.sign;
+        return result;
+    };
+    if (exp < 0) {
+        /* FIXME: underflow */
+        /* return signed zero */
+        result.parts.mantisa = 0x0;
+        result.parts.exp = 0x0;
+        return result;
+    };
+    mant1 = a.parts.mantisa;
+    if (a.parts.exp > 0) {
+        mant1 |= FLOAT64_HIDDEN_BIT_MASK;
+    } else {
+        ++exp;
+    };
+    mant2 = b.parts.mantisa;
+    if (b.parts.exp > 0) {
+        mant2 |= FLOAT64_HIDDEN_BIT_MASK;
+    } else {
+        ++exp;
+    };
+    mant1 <<= 1; /* one bit space for rounding */
+    mul64integers(mant1, mant2, &mant1, &mant2);
+/* round and return */
+    /* FIXME: ugly soulution is to shift whole mant2 >> as in 32bit version
+     * Here is is more slower because we have to shift two numbers with carry
+     * Better is find first nonzero bit and make only one shift
+     * Third version is to shift both numbers a bit to right and result will be then
+     * placed in higher part of result. Then lower part will be good only for rounding.
+     */
+    while ((exp < FLOAT64_MAX_EXPONENT) && (mant2 > 0 )) {
+        mant1 >>= 1;
+        mant1 &= ((mant2 & 0x1) << 63);
+        mant2 >>= 1;
+        ++exp;
+    }
+    while ((exp < FLOAT64_MAX_EXPONENT) && (mant1 >= ( (__u64)1 << (FLOAT64_MANTISA_SIZE + 2)))) {
+        ++exp;
+        mant1 >>= 1;
+    };
+    /* rounding */
+    //++mant1; /* FIXME: not works - without it is ok */
+    mant1 >>= 1; /* shift off rounding space */
+    if ((exp < FLOAT64_MAX_EXPONENT) && (mant1 >= ((__u64)1 << (FLOAT64_MANTISA_SIZE + 1)))) {
+        ++exp;
+        mant1 >>= 1;
+    };
+    if (exp >= FLOAT64_MAX_EXPONENT ) {
+        /* TODO: fix overflow */
+        /* return infinity*/
+        result.parts.exp = FLOAT64_MAX_EXPONENT;
+        result.parts.mantisa = 0x0;
+        return result;
+    }
+    exp -= FLOAT64_MANTISA_SIZE;
+    if (exp <= FLOAT64_MANTISA_SIZE) {
+        /* denormalized number */
+        mant1 >>= 1; /* denormalize */
+        while ((mant1 > 0) && (exp < 0)) {
+            mant1 >>= 1;
+            ++exp;
+        };
+        if (mant1 == 0) {
+            /* FIXME : underflow */
+        result.parts.exp = 0;
+        result.parts.mantisa = 0;
+        return result;
+        };
+    };
+    result.parts.exp = exp;
+    result.parts.mantisa = mant1 & ( ((__u64)1 << FLOAT64_MANTISA_SIZE) - 1);
     return result;
+}
+/** Multiply two 64 bit numbers and return result in two parts
+ * @param a first operand
+ * @param b second operand
+ * @param lo lower part from result
+ * @param hi higher part of result
+ */
+void mul64integers(__u64 a,__u64 b, __u64 *lo, __u64 *hi)
+{
+    __u64 low, high, middle1, middle2;
+    __u32 alow, blow;
+    alow = a & 0xFFFFFFFF;
+    blow = b & 0xFFFFFFFF;
+    a <<= 32;
+    b <<= 32;
+    low = (__u64)alow * blow;
+    middle1 = a * blow;
+    middle2 = alow * b;
+    high = a * b;
+    middle1 += middle2;
+    high += ((__u64)(middle1 < middle2) << 32) + middle1>>32;
+    middle1 << 32;
+    low += middle1;
+    high += (low < middle1);
+    *lo = low;
+    *hi = high;
+    return;
+}

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(root)/uspace/trunk/softfloat/generic/mul.c – Rev 731 → 737