[DF] Replace various bitmaps with HARD_REG_SETs

[Dimitrios Apostolou <jimis at gmx dot net>]

Hello list,

attached is a fairly intrusive patch that replaces many bitmaps in DF with 
HARD_REG_SETs. Tested on i386 - no regressions (besides mudflaps). Maybe 
we somehow should test on pa and mips, since I (slightly) touch those too.

Rationale is that it's a nice clean-up, avoiding the complex bitmap type 
when not needed, and making more clear the logic. I did these changes 
while doing some performance-related work on DF, which I'll hopefully post 
soon. Thanks to Paolo Bonzini for explaining the unexplicable. :-)

Performance measured unaffected:

trunk   : 0.627s, 1438.4 M instr
hardregs: 0.624s, 1434.2 M instr

(numbers differ from previous posts because I changed checks to 
--enable-checking=release)

This patch *includes* previously submitted patch that eliminates 
regs_invalidated_by_call_regset, since it's closely related and I got no 
replies on that one. It would be nice to commit together with the patch 
with subject "added some assert checks in hard-reg-set.h", these 
assertions are really useful now.

ChangeLog (emacs rescued me on style issues, Steven please let me know if 
you see any):


2011-07-27  Dimitrios Apostolou  <jimis@gmx.net>

	* DataFlow: Use HARD_REG_SETs instead of bitmaps where we are
	certain that we don't map regs above FIRST_PSEUDO_REGISTERS.
	Detailed changelog follows.

	* regset.h:   Eliminated regs_invalidated_by_call_regset bitmap,
	use instead the original regs_invalidated_by_call HARD_REG_SET.
	* reginfo.c (initial_reg_alloc_order, init_reg_sets_1)
	(globalize_reg): Eliminate all initialising and handling of
	regs_invalidated_by_call_regset.
	* df.h: changed the following variables from bitmaps to
	HARD_REG_SETs: hardware_regs_used, regular_block_artificial_uses,
	eh_block_artificial_uses, entry_block_defs,
	exit_block_uses. Declared new function df_print_hard_reg_set.
	* target.def: removed hook_void_bitmap, added
	hook_void_hard_reg_set to be used by TARGET_EXTRA_LIVE_ON_ENTRY.
	* target.h: included hard-reg-set.h
	* targhooks.h, targhooks.c: Removed hook_void_bitmap, added
	hook_void_hard_reg_set.
	* i386.c (ix86_live_on_entry), mips.c (mips_extra_live_on_entry),
	pa.c (pa_extra_live_on_entry) : changed argument from bitmap to
	HARD_REG_SET *, also changed relevant set_bit operations.
	* tm.texi: Documented type of TARGET_EXTRA_LIVE_ON_ENTRY is now
	HARD_REG_SET * instead of bitmap.
	* dce.c (dce_process_block, fast_dce):
	* df-core.c (df_print_hard_reg_set): new function to print
	HARD_REG_SET to file.
	* df-problems.c (df_rd_local_compute, df_lr_local_compute)
	(df_lr_confluence_0, df_lr_confluence_n, df_word_lr_local_compute)
	(df_simulate_fixup_sets, df_md_confluence_n): replaced old bitmap
	operations with HARD_REG_SET ones, appropriate for new types.
	(df_word_lr_local_compute): eliminated unreachable code.
	(bitmap_copy_from_hard_reg_set, bitmap_ior_from_hard_reg_set)
	(bitmap_ior_and_compl_from_hard_reg_set): new functions for
	operations between bitmaps and hard_reg_sets.
	* df-scan.c: regs_ever_live converted from bool array to
	HARD_REG_SET.
	(df_regs_ever_live_p, df_set_regs_ever_live)
	(df_compute_regs_ever_live, ): use HARD_REG_SET_BIT,
	HARD_REG_CLEAR_BIT and HARD_REG_TEST_BIT instead of bitmap
	operations, to access regs_ever_live.
	(df_scan_free_internal, df_scan_alloc)
	(df_scan_start_dump, df_scan_blocks, df_get_call_refs)
	(df_bb_refs_collect, df_get_regular_block_artificial_uses)
	(df_get_regular_block_artificial_uses)
	(df_get_eh_block_artificial_uses, df_mark_reg)
	(df_get_entry_block_def_set, df_entry_block_defs_collect)
	(df_record_entry_block_defs, df_update_entry_block_defs)
	(df_get_exit_block_use_set, df_exit_block_uses_collect)
	(df_record_exit_block_uses, df_update_exit_block_uses)
	(df_entry_block_bitmap_verify, df_exit_block_bitmap_verify)
	(df_scan_verify): use HARD_REG_SET operations instead of bitmap
	ones to access changed types.
	(df_update_entry_block_defs, df_update_exit_block_uses):
	eliminate some dead code.



Thanks,
Dimitris


P.S. CC'd DF maintainers, please add to the CC list others I might have 
missed.

Attachment: hardregs.diff
Description: Text document