diff options
Diffstat (limited to 'gcc/reload.cc')
| -rw-r--r-- | gcc/reload.cc | 15 |
1 files changed, 9 insertions, 6 deletions
diff --git a/gcc/reload.cc b/gcc/reload.cc index 664082a..3ed901e 100644 --- a/gcc/reload.cc +++ b/gcc/reload.cc @@ -3635,9 +3635,11 @@ find_reloads (rtx_insn *insn, int replace, int ind_levels, int live_known, a hard reg and this alternative accepts some register, see if the class that we want is a subset of the preferred class for this register. If not, - but it intersects that class, use the preferred class - instead. If it does not intersect the preferred - class, show that usage of this alternative should be + but it intersects that class, we'd like to use the + intersection, but the best we can do is to use the + preferred class, if it is instead a subset of the + class we want in this alternative. If we can't use + it, show that usage of this alternative should be discouraged; it will be discouraged more still if the register is `preferred or nothing'. We do this because it increases the chance of reusing our spill @@ -3664,9 +3666,10 @@ find_reloads (rtx_insn *insn, int replace, int ind_levels, int live_known, if (! reg_class_subset_p (this_alternative[i], preferred_class[i])) { - /* Since we don't have a way of forming the intersection, - we just do something special if the preferred class - is a subset of the class we have; that's the most + /* Since we don't have a way of forming a register + class for the intersection, we just do + something special if the preferred class is a + subset of the class we have; that's the most common case anyway. */ if (reg_class_subset_p (preferred_class[i], this_alternative[i])) |