Postreload and STRICT_LOW_PART

[Andreas Schwab]

Why is postreload converting (set (REGX) (CONST_INT A)) ... (set (REGX)
(CONST_INT B)) into (set (STRICT_LOW_PART (REGX)) (CONST_INT B))?  That
looks like a pessimisation especially if the constants are small, since
STRICT_LOW_PART must not touch the high part.  Is there a way for the
backend to stop postreload from doing this if the constants are in some
range?  On the m68k, loading a constant in the range -128..127 in SI
mode is better than loading it in strict QI mode.

Andreas.

-- 
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."