speeded up a bit for converting 0.0 to string

diff --git a/modules/src/flt_arith/flt_ar2flt.c b/modules/src/flt_arith/flt_ar2flt.c
index ad1eaec..505f55e 100644 (file)
--- a/modules/src/flt_arith/flt_ar2flt.c
+++ b/modules/src/flt_arith/flt_ar2flt.c
@@ -8,7 +8,7 @@
 #include "misc.h"
 #include <em_arith.h>
 
-flt_arith2flt(n, e)
+flt_arith2flt(n, e, uns)
        register arith n;
        register flt_arith *e;
 {
@@ -16,7 +16,7 @@ flt_arith2flt(n, e)
        */
        register int i;
 
-       if (n < 0) {
+       if (!uns && n < 0) {
                e->flt_sign = 1;
                n = -n;
        }
@@ -27,16 +27,11 @@ flt_arith2flt(n, e)
                return;
        }
        e->flt_exp = 63;
-       if (n < 0) {
-               /* n = MINARITH */
-               n = 0x40000000;
-               while ((n << 1) > 0) n <<= 1;
-               e->flt_exp++;
-       }
+               
        for (i = 64; i > 0 && n != 0; i--) {
                flt_b64_sft(&(e->flt_mantissa),1);
                e->m1 |= (n & 1) << 31;
-               n >>= 1;
+               n = (n >> 1) & ~(0x80 << 8*(sizeof(arith)-1));
        }
 
        if (i > 0) {

diff --git a/modules/src/flt_arith/flt_arith.3 b/modules/src/flt_arith/flt_arith.3
index 20769b0..983d017 100644 (file)
--- a/modules/src/flt_arith/flt_arith.3
+++ b/modules/src/flt_arith/flt_arith.3
@@ -61,12 +61,14 @@ extern int  flt_status;
 .B int flt_status;
 .PP
 .B #include <em_arith.h>
-.B flt_arith2flt(n, e)
+.B flt_arith2flt(n, e, uns)
 .B arith n;
 .B flt_arith *e;
+.B int uns;
 .PP
-.B arith flt_flt2arith(e)
+.B arith flt_flt2arith(e, uns)
 .B flt_arith *e;
+.B int uns;
 .PP
 .B flt_b64_sft(m, n)
 .B struct flt_mantissa *m;
@@ -184,14 +186,20 @@ converts the number
 .I n
 to the floating point format used in this package and returns the result
 in
-.IR e .
+.IR e . If the
+.I uns
+flag is set, the number
+.I n
+is regarded as an unsigned.
 .PP
 .B flt_flt2arith
 truncates the number indicated by
 .I e
 to the largest integer value smaller than or equal to the number indicated by
 .IR e .
-It returns this value.
+It returns this value. If the
+.I uns
+flag is set, the result is to be regarded as unsigned.
 .PP
 Before each operation, the
 .I flt_status

diff --git a/modules/src/flt_arith/flt_flt2ar.c b/modules/src/flt_arith/flt_flt2ar.c
index eefc51d..ed885b8 100644 (file)
--- a/modules/src/flt_arith/flt_flt2ar.c
+++ b/modules/src/flt_arith/flt_flt2ar.c
@@ -9,15 +9,21 @@
 #include <em_arith.h>
 
 arith
-flt_flt2arith(e)
+flt_flt2arith(e, uns)
        register flt_arith *e;
 {
        /*      Convert the flt_arith "n" to an arith.
        */
        arith   n;
        struct flt_mantissa a;
+       register int i;
 
+       if (uns) uns = 1;
        flt_status = 0;
+       if (e->flt_sign && uns) {
+               flt_status = FLT_UNFL;
+               return 0;
+       }
        if (e->flt_exp < 0) {
                /* absolute value of result < 1.
                   Return value only depends on sign:
@@ -25,31 +31,33 @@ flt_flt2arith(e)
                return -e->flt_sign;
        }
 
-       if (e->flt_exp > (8*sizeof(arith)-2)) {
+       if (e->flt_exp > 8*sizeof(arith)-2 + uns) {
                /* probably overflow, but there is one exception:
                */
-               if (e->flt_sign) {
-                       n = 0x80;
-                       while (n << 8) n <<= 8;
-                       if (e->flt_exp == 8*sizeof(arith)-1 &&
-                           e->m2 == 0 &&
-                           e->m1 == 0x80000000) {
-                               /* No overflow in this case */
-                       }
-                       else flt_status = FLT_OVFL;
-                       return n;
+               if (e->flt_sign &&
+                   e->flt_exp == 8*sizeof(arith)-1 &&
+                   e->m2 == 0 &&
+                   e->m1 == 0x80000000) {
+                       /* No overflow in this case */
+                       flt_status = 0;
                }
-               n = 0x7F;
-               while ((n << 8) > 0) {
-                       n <<= 8;
-                       n |= 0xFF;
+               else {
+                       flt_status = FLT_OVFL;
+                       e->flt_exp = 8*sizeof(arith)-2 + uns + e->flt_sign;
+                       if (e->flt_sign) {
+                               e->m1 = 0x80000000;
+                               e->m2 = 0;
+                       }
+                       else {
+                               e->m1 = 0xFFFFFFFF;
+                               e->m2 = 0xFFFFFFFF;
+                       }
                }
-               return n;
        }
        
        a = e->flt_mantissa;
        flt_b64_sft(&a, 63-e->flt_exp);
        n = a.flt_l_32 | ((a.flt_h_32 << 16) << 16);
        /* not << 32; this could be an undefined operation */
-       return n;
+       return e->flt_sign ? -n : n;
 }

diff --git a/modules/src/flt_arith/flt_str2fl.c b/modules/src/flt_arith/flt_str2fl.c
index f6431de..2974321 100644 (file)
--- a/modules/src/flt_arith/flt_str2fl.c
+++ b/modules/src/flt_arith/flt_str2fl.c
@@ -347,7 +347,7 @@ flt_ecvt(e, ndigit, decpt, sign)
                (*decpt)++;     /* because now value in [1.0, 10.0) */
        }
        while (p <= pe) {
-               if (e->flt_exp >= 0) {
+               if (e->flt_exp >= 0 && e->m1 != 0) {
                        flt_arith x;
 
                        x.m2 = 0; x.flt_exp = e->flt_exp;
@@ -355,8 +355,10 @@ flt_ecvt(e, ndigit, decpt, sign)
                        x.m1 = (e->m1 >> 1) & 0x7FFFFFFF;
                        x.m1 = x.m1>>(30-e->flt_exp);
                        *p++ = (x.m1) + '0';
-                       x.m1 = x.m1 << (31-e->flt_exp);
-                       flt_add(e, &x, e);
+                       if (x.m1) {
+                               x.m1 = x.m1 << (31-e->flt_exp);
+                               flt_add(e, &x, e);
+                       }
                }
                else *p++ = '0';
                flt_mul(e, &s10pow[1], e);