Libc-594.1.4.tar.gz

[apple/libc.git] / gdtoa / FreeBSD / gdtoa-dtoa.c

diff --git a/gdtoa/FreeBSD/gdtoa-dtoa.c b/gdtoa/FreeBSD/gdtoa-dtoa.c
index 20e240590c3e44294732f9e626e7f63ba6688dfb..48fdf5efc2da1388738cdfaf554f08339cdd671f 100644 (file)
--- a/gdtoa/FreeBSD/gdtoa-dtoa.c
+++ b/gdtoa/FreeBSD/gdtoa-dtoa.c
@@ -26,21 +26,15 @@ THIS SOFTWARE.
 
 ****************************************************************/
 
-/* Please send bug reports to
-       David M. Gay
-       Bell Laboratories, Room 2C-463
-       600 Mountain Avenue
-       Murray Hill, NJ 07974-0636
-       U.S.A.
-       dmg@bell-labs.com
- */
+/* Please send bug reports to David M. Gay (dmg at acm dot org,
+ * with " at " changed at "@" and " dot " changed to ".").     */
 
 #include "gdtoaimp.h"
 
 /* dtoa for IEEE arithmetic (dmg): convert double to ASCII string.
  *
  * Inspired by "How to Print Floating-Point Numbers Accurately" by
- * Guy L. Steele, Jr. and Jon L. White [Proc. ACM SIGPLAN '90, pp. 92-101].
+ * Guy L. Steele, Jr. and Jon L. White [Proc. ACM SIGPLAN '90, pp. 112-126].
  *
  * Modifications:
  *     1. Rather than iterating, we use a simple numeric overestimate
@@ -72,7 +66,6 @@ THIS SOFTWARE.
  */
 
 #ifdef Honor_FLT_ROUNDS
-#define Rounding rounding
 #undef Check_FLT_ROUNDS
 #define Check_FLT_ROUNDS
 #else
@@ -133,12 +126,22 @@ dtoa
        Bigint *b, *b1, *delta, *mlo, *mhi, *S;
        double d2, ds, eps;
        char *s, *s0;
-#ifdef Honor_FLT_ROUNDS
-       int rounding;
-#endif
 #ifdef SET_INEXACT
        int inexact, oldinexact;
 #endif
+#ifdef Honor_FLT_ROUNDS /*{*/
+       int Rounding;
+#ifdef Trust_FLT_ROUNDS /*{{ only define this if FLT_ROUNDS really works! */
+       Rounding = Flt_Rounds;
+#else /*}{*/
+       Rounding = 1;
+       switch(fegetround()) {
+         case FE_TOWARDZERO:   Rounding = 0; break;
+         case FE_UPWARD:       Rounding = 2; break;
+         case FE_DOWNWARD:     Rounding = 3;
+         }
+#endif /*}}*/
+#endif /*}*/
 
 #ifndef MULTIPLE_THREADS
        if (dtoa_result) {
@@ -184,12 +187,12 @@ dtoa
        inexact = 1;
 #endif
 #ifdef Honor_FLT_ROUNDS
-       if ((rounding = Flt_Rounds) >= 2) {
+       if (Rounding >= 2) {
                if (*sign)
-                       rounding = rounding == 2 ? 0 : 2;
+                       Rounding = Rounding == 2 ? 0 : 2;
                else
-                       if (rounding != 2)
-                               rounding = 0;
+                       if (Rounding != 2)
+                               Rounding = 0;
                }
 #endif
 
@@ -322,7 +325,7 @@ dtoa
        s = s0 = rv_alloc(i);
 
 #ifdef Honor_FLT_ROUNDS
-       if (mode > 1 && rounding != 1)
+       if (mode > 1 && Rounding != 1)
                leftright = 0;
 #endif
 
@@ -459,7 +462,7 @@ dtoa
                        if (i == ilim) {
 #ifdef Honor_FLT_ROUNDS
                                if (mode > 1)
-                               switch(rounding) {
+                               switch(Rounding) {
                                  case 0: goto ret1;
                                  case 2: goto bump_up;
                                  }
@@ -527,7 +530,7 @@ dtoa
        spec_case = 0;
        if ((mode < 2 || leftright)
 #ifdef Honor_FLT_ROUNDS
-                       && rounding == 1
+                       && Rounding == 1
 #endif
                                ) {
                if (!word1(d) && !(word0(d) & Bndry_mask)
@@ -620,7 +623,7 @@ dtoa
 #ifndef ROUND_BIASED
                        if (j1 == 0 && mode != 1 && !(word1(d) & 1)
 #ifdef Honor_FLT_ROUNDS
-                               && rounding >= 1
+                               && Rounding >= 1
 #endif
                                                                   ) {
                                if (dig == '9')
@@ -648,7 +651,7 @@ dtoa
                                        }
 #ifdef Honor_FLT_ROUNDS
                                if (mode > 1)
-                                switch(rounding) {
+                                switch(Rounding) {
                                  case 0: goto accept_dig;
                                  case 2: goto keep_dig;
                                  }
@@ -666,7 +669,7 @@ dtoa
                                }
                        if (j1 > 0) {
 #ifdef Honor_FLT_ROUNDS
-                               if (!rounding)
+                               if (!Rounding)
                                        goto accept_dig;
 #endif
                                if (dig == '9') { /* possible if i == 1 */
@@ -709,7 +712,7 @@ dtoa
        /* Round off last digit */
 
 #ifdef Honor_FLT_ROUNDS
-       switch(rounding) {
+       switch(Rounding) {
          case 0: goto trimzeros;
          case 2: goto roundoff;
          }