+2002-05-16 Dale Johannesen <dalej@apple.com>
+
+ * combine.c (cant_combine_insn_p): Reenable combinations
+ involving hard regs unless CLASS_LIKELY_SPILLED_P.
+
2002-05-16 Neil Booth <neil@daikokuya.demon.co.uk>
* c-common.c (cb_register_builtins): Handle more built-ins
if (! INSN_P (insn))
return 1;
- /* Never combine loads and stores involving hard regs. The register
- allocator can usually handle such reg-reg moves by tying. If we allow
- the combiner to make substitutions of hard regs, we risk aborting in
- reload on machines that have SMALL_REGISTER_CLASSES.
+ /* Never combine loads and stores involving hard regs that are likely
+ to be spilled. The register allocator can usually handle such
+ reg-reg moves by tying. If we allow the combiner to make
+ substitutions of likely-spilled regs, we may abort in reload.
As an exception, we allow combinations involving fixed regs; these are
not available to the register allocator so there's no risk involved. */
dest = SUBREG_REG (dest);
if (REG_P (src) && REG_P (dest)
&& ((REGNO (src) < FIRST_PSEUDO_REGISTER
- && ! fixed_regs[REGNO (src)])
+ && ! fixed_regs[REGNO (src)]
+ && CLASS_LIKELY_SPILLED_P (REGNO_REG_CLASS (REGNO (src))))
|| (REGNO (dest) < FIRST_PSEUDO_REGISTER
- && ! fixed_regs[REGNO (dest)])))
+ && ! fixed_regs[REGNO (dest)]
+ && CLASS_LIKELY_SPILLED_P (REGNO_REG_CLASS (REGNO (dest))))))
return 1;
return 0;