r275536 - in /trunk/gcc: ChangeLog array-traits...

[rsandifo@gcc.gnu.org]

Author: rsandifo
Date: Mon Sep  9 18:01:47 2019
New Revision: 275536

URL: https://gcc.gnu.org/viewcvs?rev=275536&root=gcc&view=rev
Log:
Add "fast" conversions from arrays to bitmaps

This patch adds a bitmap_view<X> class that creates a read-only,
on-stack bitmap representation of an array-like object X.  The main
use case is to allow HARD_REG_SETs to be used in REG_SET (i.e. bitmap)
operations.

For now it only handles constant-sized arrays, but I've tried to
define the types in a way that could handle variable-sized arrays
in future (although less efficiently).  E.g. this might be useful
for combining bitmaps and sbitmaps.

For the read-only view to work as intended, I needed to make
bitmap_bit_p take a const_bitmap instead of a bitmap.  Logically
the bitmap really is read-only, but we update the "current" and
"indx" fields of the bitmap_head after doing a search.

2019-09-09  Richard Sandiford  <richard.sandiford@arm.com>

gcc/
	* array-traits.h: New file.
	* coretypes.h (array_traits, bitmap_view): New types.
	* bitmap.h: Include "array-traits.h"
	(bitmap_bit_p): Take a const_bitmap instead of a bitmap.
	(base_bitmap_view, bitmap_view): New classes.
	* bitmap.c (bitmap_bit_p): Take a const_bitmap instead of a bitmap.
	* hard-reg-set.h: Include array-traits.h.
	(array_traits<HARD_REG_SET>): New struct.
	* regset.h (IOR_REG_SET_HRS): New macro.
	* loop-iv.c (simplify_using_initial_values): Use IOR_REG_SET_HRS
	rather than iterating over each hard register.
	* sched-deps.c (sched_analyze_insn): Likewise.
	* sel-sched-ir.c (setup_id_implicit_regs): Likewise.

Added:
    trunk/gcc/array-traits.h
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/bitmap.c
    trunk/gcc/bitmap.h
    trunk/gcc/coretypes.h
    trunk/gcc/hard-reg-set.h
    trunk/gcc/loop-iv.c
    trunk/gcc/regset.h
    trunk/gcc/sched-deps.c
    trunk/gcc/sel-sched-ir.c