6888x packed decimal full k-factor support.

diff --git a/fpp.cpp b/fpp.cpp
index 5044d7472d0a309f3bc5128ab6f7dc4d7fbfc459..50f36d024fedeea792c97109d053a2d4171454b4 100644 (file)
--- a/fpp.cpp
+++ b/fpp.cpp
@@ -1,10 +1,11 @@
 /*
 * UAE - The Un*x Amiga Emulator
 *
-* MC68881 emulation
+* MC68881/68882/68040/68060 FPU emulation
 *
 * Copyright 1996 Herman ten Brugge
 * Modified 2005 Peter Keunecke
+* 68040+ exceptions and more by Toni Wilen
 */
 
 #define __USE_ISOC9X  /* We might be able to pick up a NaN */
@@ -533,7 +534,7 @@ static int get_fpu_version (void)
                v = 0x1f;
                break;
        case 68882:
-               v = 0x20; /* ??? */
+               v = 0x20;
                break;
        case 68040:
                v = 0x41;
@@ -598,9 +599,28 @@ STATIC_INLINE tointtype toint (fptype src, fptype minval, fptype maxval)
 #endif
 }
 
+static bool fpu_isnan (fptype fp)
+{
+#ifdef HAVE_ISNAN
+       return isnan (fp) != 0;
+#else
+       return false;
+#endif
+}
+static bool fpu_isinfinity (fptype fp)
+{
+#ifdef _MSC_VER
+       return !_finite (fp);
+#elif defined(HAVE_ISINF)
+       return _isinf (fp);
+#else
+       return false;
+#endif
+}
+
 uae_u32 get_fpsr (void)
 {
-       uae_u32 answer = regs.fpsr & 0x00ffffff;
+       uae_u32 answer = regs.fpsr & 0x00ff00f8;
 
        // exception status byte
        if (regs.fp_result_status & FE_INEXACT)
@@ -615,30 +635,40 @@ uae_u32 get_fpsr (void)
                answer |= 1 << 13;
 
        // accrued exception byte
-       answer |= (answer >> 6) & (0x80 | 0x40 | 0x20 | 0x10 | 0x08);
+       if (answer & ((1 << 14)  | (1 << 13)))
+               answer |= 0x80; // IOP = SNAN | OPERR
+       if (answer & (1 << 12))
+               answer |= 0x40; // OVFL = OVFL
+       if (answer & (1 << 11) | (1 << 9))
+               answer |= 0x20; // UNFL = UNFL | INEX2
+       if (answer & (1 << 10))
+               answer |= 0x10; // DZ = DZ
+       if (answer & ((1 << 12) | (1 << 9) | (1 << 8)))
+               answer |= 0x08; // INEX = INEX1 | INEX2 | OVFL 
+
+       regs.fpsr = answer;
 
        // condition code byte
-#ifdef HAVE_ISNAN
-       if (isnan (regs.fp_result.fp))
+       if (fpu_isnan (regs.fp_result.fp))
                answer |= 1 << 24;
        else
-#endif
        {
                if (regs.fp_result.fp == 0)
                        answer |= 1 << 26;
                else if (regs.fp_result.fp < 0)
                        answer |= 1 << 27;
-#ifdef _MSC_VER
-               if (!_finite (regs.fp_result.fp))
-                       answer |= 1 << 25;
-#elif HAVE_ISINF
-               if (_isinf (regs.fp_result.fp))
+               if (fpu_isinfinity (regs.fp_result.fp))
                        answer |= 1 << 25;
-#endif
        }
        return answer;
 }
 
+static void update_fpsr (uae_u32 v)
+{
+       regs.fp_result_status = FE_INVALID;
+       get_fpsr ();
+}
+
 STATIC_INLINE void set_fpsr (uae_u32 x)
 {
        regs.fpsr = x;
@@ -718,63 +748,142 @@ static fptype to_pack (uae_u32 *wrd)
        return d;
 }
 
-// TODO: Positive k-Factor.
-static void from_pack (fptype src, uae_u32 *wrd, int kfactor)
+void from_pack (fptype src, uae_u32 *wrd, int kfactor)
 {
-       int i, t, precision;
-       char *cp;
+       int i, j, t;
+       int exp;
+       int ndigits;
+       char *cp, *strp;
        char str[100];
 
-       precision = kfactor <= 0 ? -kfactor : 16;
-       if (precision > 16)
-               precision = 16;
+       wrd[0] = wrd[1] = wrd[2] = 0;
+
+       if (fpu_isnan (src) || fpu_isinfinity (src)) {
+               wrd[0] |= (1 << 30) | (1 << 29) | (1 << 30); // YY=1
+               wrd[0] |= 0xfff << 16; // Exponent=FFF
+               // TODO: mantissa should be set if NAN
+               return;
+       }
+
 #if USE_LONG_DOUBLE
-       sprintf (str, "%#.*Le", precision, src);
+       sprintf (str, "%#.17Le", src);
 #else
-       sprintf (str, "%#.*e", precision, src);
+       sprintf (str, "%#.17e", src);
 #endif
+       
+       // get exponent
        cp = str;
-       wrd[0] = wrd[1] = wrd[2] = 0;
-       if (*cp == '-') {
-               cp++;
-               wrd[0] = 0x80000000;
-       }
+       while (*cp++ != 'e');
        if (*cp == '+')
                cp++;
-       wrd[0] |= (*cp++ - '0');
-       if (*cp == '.')
+       exp = atoi (cp);
+
+       // remove trailing zeros
+       cp = str;
+       while (*cp != 'e')
                cp++;
-       for (i = 0; i < 8; i++) {
-               wrd[1] <<= 4;
-               if (*cp >= '0' && *cp <= '9')
-                       wrd[1] |= *cp++ - '0';
-       }
-       for (i = 0; i < 8; i++) {
-               wrd[2] <<= 4;
-               if (*cp >= '0' && *cp <= '9')
-                       wrd[2] |= *cp++ - '0';
+       cp[0] = 0;
+       cp--;
+       while (cp > str && *cp == '0') {
+               *cp = 0;
+               cp--;
        }
-       if (*cp == 'e') {
+
+       cp = str;
+       // get sign
+       if (*cp == '-') {
                cp++;
-               if (*cp == '-') {
-                       cp++;
-                       wrd[0] |= 0x40000000;
+               wrd[0] = 0x80000000;
+       } else if (*cp == '+') {
+               cp++;
+       }
+       strp = cp;
+
+       if (kfactor <= 0) {
+               ndigits = abs (exp) + (-kfactor) + 1;
+       } else {
+               if (kfactor > 17) {
+                       kfactor = 17;
+                       update_fpsr (FE_INVALID);
                }
-               if (*cp == '+')
-                       cp++;
-               t = 0;
-               while (cp[0] && cp[1])
-                       cp++;
-               for (i = 0; i < 3; i++) {
-                       char c = *cp;
-                       t >>= 4;
-                       if (*cp >= '0' && *cp <= '9') {
-                               t |= (c - '0') << (2 * 4);
-                               cp--;
+               ndigits = kfactor;
+       }
+
+       if (ndigits < 0)
+               ndigits = 0;
+       if (ndigits > 16)
+               ndigits = 16;
+
+       // remove decimal point
+       strp[1] = strp[0];
+       strp++;
+       // add trailing zeros
+       i = strlen (strp);
+       cp = strp + i;
+       while (i < ndigits) {
+               *cp++ = '0';
+               i++;
+       }
+       i = ndigits + 1;
+       while (i < 17) {
+               strp[i] = 0;
+               i++;
+       }
+       *cp = 0;
+       i = ndigits - 1;
+       // need to round?
+       if (i >= 0 && strp[i + 1] >= '5') {
+               while (i >= 0) {
+                       strp[i]++;
+                       if (strp[i] <= '9')
+                               break;
+                       if (i == 0) {
+                               strp[i] = '1';
+                               exp++;
+                       } else {
+                               strp[i] = '0';
                        }
+                       i--;
+               }
+       }
+       strp[ndigits] = 0;
+
+       // store first digit of mantissa
+       cp = strp;
+       wrd[0] |= *cp++ - '0';
+
+       // store rest of mantissa
+       for (j = 1; j < 3; j++) {
+               for (i = 0; i < 8; i++) {
+                       wrd[j] <<= 4;
+                       if (*cp >= '0' && *cp <= '9')
+                               wrd[j] |= *cp++ - '0';
                }
-               wrd[0] |= t << 16;
        }
+
+       // exponent
+       if (exp < 0) {
+               wrd[0] |= 0x40000000;
+               exp = -exp;
+       }
+       if (exp > 9999) // ??
+               exp = 9999;
+       if (exp > 999) {
+               int d = exp / 1000;
+               wrd[0] |= d << 12;
+               exp -= d * 1000;
+               update_fpsr (FE_INVALID);
+       }
+       i = 100;
+       t = 0;
+       while (i >= 1) {
+               int d = exp / i;
+               t <<= 4;
+               t |= d;
+               exp -= d * i;
+               i /= 10;
+       }
+       wrd[0] |= t << 16;
 }
 
 static int get_fp_value (uae_u32 opcode, uae_u16 extra, fpdata *src, uaecptr oldpc, uae_u32 *adp)