* lower-subreg.c (find_decomposable_subregs): Don't decompose
subregs which have a cast between modes which are not tieable.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@125265
138bc75d-0d04-0410-961f-
82ee72b054a4
+2007-06-01 Ian Lance Taylor <iant@google.com>
+
+ PR rtl-optimization/31455
+ * lower-subreg.c (find_decomposable_subregs): Don't decompose
+ subregs which have a cast between modes which are not tieable.
+
2007-06-01 Uros Bizjak <ubizjak@gmail.com>
* expr.c (force_operand) [DIV, MOD, UDIV, UMOD, ASHIFTRT]: Remove
bitmap_set_bit (decomposable_context, regno);
return -1;
}
+
+ /* If this is a cast from one mode to another, where the modes
+ have the same size, and they are not tieable, then mark this
+ register as non-decomposable. If we decompose it we are
+ likely to mess up whatever the backend is trying to do. */
+ if (outer_words > 1
+ && outer_size == inner_size
+ && !MODES_TIEABLE_P (GET_MODE (x), GET_MODE (inner)))
+ {
+ bitmap_set_bit (non_decomposable_context, regno);
+ return -1;
+ }
}
else if (REG_P (x))
{