@@ -1736,6 +1736,68 @@ bit_value_binop (enum tree_code code, signop sgn, int width,
break;
}
+ case TRUNC_MOD_EXPR:
+ {
+ widest_int r1max = r1val | r1mask;
+ widest_int r2max = r2val | r2mask;
+ if (sgn == UNSIGNED
+ || (!wi::neg_p (r1max) && !wi::neg_p (r2max)))
+ {
+ /* Confirm R2 has some bits set, to avoid division by zero. */
+ widest_int r2min = wi::bit_and_not (r2val, r2mask);
+ if (r2min != 0)
+ {
+ /* R1 % R2 is R1 if R1 is always less than R2. */
+ if (wi::ltu_p (r1max, r2min))
+ {
+ *mask = r1mask;
+ *val = r1val;
+ }
+ else
+ {
+ /* R1 % R2 is always less than the maximum of R2. */
+ unsigned int lzcount = wi::clz (r2max);
+ unsigned int bits = wi::get_precision (r2max) - lzcount;
+ if (r2max == wi::lshift (1, bits))
+ bits--;
+ *mask = wi::mask <widest_int> (bits, false);
+ *val = 0;
+ }
+ }
+ }
+ }
+ break;
+
+ case TRUNC_DIV_EXPR:
+ {
+ widest_int r1max = r1val | r1mask;
+ widest_int r2max = r2val | r2mask;
+ if (sgn == UNSIGNED
+ || (!wi::neg_p (r1max) && !wi::neg_p (r2max)))
+ {
+ /* Confirm R2 has some bits set, to avoid division by zero. */
+ widest_int r2min = wi::bit_and_not (r2val, r2mask);
+ if (r2min != 0)
+ {
+ /* R1 / R2 is zero if R1 is always less than R2. */
+ if (wi::ltu_p (r1max, r2min))
+ {
+ *mask = 0;
+ *val = 0;
+ }
+ else
+ {
+ widest_int upper = wi::udiv_trunc (r1max, r2min);
+ unsigned int lzcount = wi::clz (upper);
+ unsigned int bits = wi::get_precision (upper) - lzcount;
+ *mask = wi::mask <widest_int> (bits, false);
+ *val = 0;
+ }
+ }
+ }
+ }
+ break;
+
default:;
}
}