some fixes: representation for 0, and corrected check for overflow

diff --git a/modules/src/flt_arith/flt_chk.c b/modules/src/flt_arith/flt_chk.c
index 2a027d0..1ec3a16 100644 (file)
--- a/modules/src/flt_arith/flt_chk.c
+++ b/modules/src/flt_arith/flt_chk.c
@@ -15,12 +15,14 @@ flt_chk(e)
        if (e->flt_exp >= EXT_MAX) {
                flt_status = FLT_OVFL;
                e->flt_exp = EXT_MAX;
-               e->m1 = e->m2 = 0;
+               e->m1 = 0x80000000;
+               e->m2 = 0;
        }
        if (e->flt_exp <= EXT_MIN) {
                flt_status = FLT_UNFL;
                e->flt_exp = 0;
-               e->m1 = e->m2 = 0;
+               e->m1 = 0;
+               e->m2 = 0;
                e->flt_sign = 0;
        }
 }

diff --git a/modules/src/flt_arith/flt_cmp.c b/modules/src/flt_arith/flt_cmp.c
index fd21a9b..847c898 100644 (file)
--- a/modules/src/flt_arith/flt_cmp.c
+++ b/modules/src/flt_arith/flt_cmp.c
@@ -11,9 +11,14 @@ int
 flt_cmp(e1, e2)
        register flt_arith *e1, *e2;
 {
-       int sign = e1->flt_sign ? -1 : 1;
+       int sign;
        int tmp;
 
+       if (e1->flt_exp == 0 && e1->m1 == 0 && e1->m2 == 0 &&
+           e2->flt_exp == 0 && e2->m1 == 0 && e2->m2 == 0) {
+               return 0;
+       }
+       sign = e1->flt_sign ? -1 : 1;
        if (e1->flt_sign > e2->flt_sign) return -1;
        if (e1->flt_sign < e2->flt_sign) return 1;
        if (e1->flt_exp < e2->flt_exp) return -sign;

diff --git a/modules/src/flt_arith/flt_div.c b/modules/src/flt_arith/flt_div.c
index 82fe7b1..39134be 100644 (file)
--- a/modules/src/flt_arith/flt_div.c
+++ b/modules/src/flt_arith/flt_div.c
@@ -22,7 +22,8 @@ flt_div(e1,e2,e3)
        if ((e2->m1 | e2->m2) == 0) {
                flt_status = FLT_DIV0;
                e3->flt_exp = EXT_MAX;
-               e3->m1 = e3->m2 = 0L;
+               e3->m1 = 0x80000000;
+               e3->m2 = 0L;
                return;
        }
        if ((e1->m1 | e1->m2) == 0) {   /* 0 / anything == 0 */

diff --git a/modules/src/flt_arith/flt_nrm.c b/modules/src/flt_arith/flt_nrm.c
index 988d856..107071a 100644 (file)
--- a/modules/src/flt_arith/flt_nrm.c
+++ b/modules/src/flt_arith/flt_nrm.c
@@ -10,8 +10,11 @@
 flt_nrm(e)
        register flt_arith *e;
 {
-       if ((e->m1 | e->m2) == 0L)
+       if ((e->m1 | e->m2) == 0L) {
+               e->flt_exp = 0;
+               e->flt_sign = 0;
                return;
+       }
 
        /* if top word is zero mov low word     */
        /* to top word, adjust exponent value   */

diff --git a/modules/src/flt_arith/flt_str2fl.c b/modules/src/flt_arith/flt_str2fl.c
index bc178a1..9a3b20e 100644 (file)
--- a/modules/src/flt_arith/flt_str2fl.c
+++ b/modules/src/flt_arith/flt_str2fl.c
@@ -253,7 +253,7 @@ flt_str2flt(s, e)
        while (c = *s++, isdigit(c) || (c == '.' && ! dotseen++)) {
                if (c == '.') continue;
                digitseen = 1;
-               if (e->m1 <= 0x7FFFFFFF/5) {
+               if (e->m1 >= 0 && e->m1 <= 0x7FFFFFFF/5) {
                        struct flt_mantissa     a1;
 
                        a1 = e->flt_mantissa;
@@ -415,7 +415,7 @@ flt_flt2str(e, buf, bufsize)
                 if (*s1) *s++ = *s1++;
                 else *s++ = '0';
        }
-        if ((e->m1 | e->m2) || e->flt_exp == EXT_MIN || e->flt_exp == EXT_MAX) {
+        if (e->m1 | e->m2) {
                --dp ;
        }
        if (dp != 0) {