egcs/gcc ChangeLog loop.c loop.h fold-const.c

[Richard Henderson]

CVSROOT:	/egcs/carton/cvsfiles
Module name:	egcs
Changes by:	rth@egcs.cygnus.com	98/07/17 14:46:07

Modified files:
	gcc            : ChangeLog loop.c loop.h fold-const.c 

Log message:
	* loop.h (struct induction): Add no_const_addval.
	* loop.c (the_movables, reg_address_cost): New variables.
	(init_loop): Init reg_address_cost.
	(loop_optimize): Call end_alias_analysis.
	(scan_loop): Init the_movables.
	(record_giv): Init induction->no_const_addval.
	(basic_induction_var) [PLUS]: Use rtx_equal_p instead of ==.
	[REG]: Rearrange loop search test to catch more cases.
	(general_induction_var): Return success not benefit; take an extra
	argument for that.  Change all callers.
	(simplify_giv_expr) [PLUS]: Always combine invariants.  Use sge_plus.
	[MULT]: Use rtx_equal_p instead of ==.  Combine simple invariants.
	[default]: Search the_movables for additional combinations.
	(sge_plus_constant, sge_plus): New functions.
	(express_from_1): New function.
	(express_from): Always define.  Rewrite using express_from_1.
	(combine_givs_p): Handle more cases.  Ignore address cost.
	(cmp_combine_givs_stats): New function.
	(combine_givs_used_once, combine_givs_benefit_from): New functions.
	(combine_givs): Rewrite to do best-fit combination.
	
	* fold-const.c (operand_equal_p): Handle RTL_EXPR.
	(fold): Do a complete (A*C)+(B*C) association check.