(FPROP): Recognize 80387 or 68881 XFmode format.

From-SVN: r5410

diff --git a/gcc/enquire.c b/gcc/enquire.c
index d9e16f167889b06d820948f657e7298a1c6fac93..029fbd2ee9175b82ecd4b0e917d5845ea62e8a0f 100644 (file)
--- a/gcc/enquire.c
+++ b/gcc/enquire.c
@@ -29,6 +29,10 @@
    Richard Stallman, May 93:
    In F_check, check NO_LONG_DOUBLE_IO.
 
+   Changes by Stephen Moshier, installed Sep 93:
+   (FPROP): Recognize 80387 or 68881 XFmode format.
+
+
    COMPILING
    With luck and a following wind, just the following will work:
        cc enquire.c -o enquire
@@ -2678,6 +2682,14 @@ int FPROP(bits_per_byte) int bits_per_byte; {
        if (f_radix != 10) {
                hidden=0;
                mantbits=floor_log(2, (Long_double)f_radix)*f_mant_dig;
+               if (mantbits == 64
+                   && iexp == 15
+                   && f_max_exp+f_min_exp > 0 /* ??? f_min_exp may be wrong. */
+                   && mantbits+iexp+17 == (int)sizeof(Number)*bits_per_byte) {
+                       Vprintf("%sArithmetic probably doesn't use a hidden bit%s\n", co, oc);
+                       Vprintf("%sIt's probably 80387 or 68881 extended real%s\n", co, oc);
+                       goto is_extended;
+               }
                if (mantbits+iexp == (int)sizeof(Number)*bits_per_byte) {
                        hidden=1;
                        Vprintf("%sArithmetic uses a hidden bit%s\n", co, oc);
@@ -2698,6 +2710,7 @@ int FPROP(bits_per_byte) int bits_per_byte; {
                                    f_mant_dig==53 ? "double" :
                                    f_mant_dig >53 ? "extended" :
                                                "some", oc);
+is_extended:
                        if (f_rounds != 1 || normal) {
                                Vprintf("%s   though ", co);
                                if (f_rounds != 1) {