st_expr Struct Reference

Collaboration diagram for st_expr:

Data Fields
rtx	pattern
vec< rtx >	pattern_regs
vec< rtx_insn * >	antic_stores
vec< rtx_insn * >	avail_stores
struct st_expr *	next
int	index
unsigned int	hash_index
rtx	reaching_reg

Detailed Description

Store motion via Lazy Code Motion on the reverse CFG.
   Copyright (C) 1997-2024 Free Software Foundation, Inc.

This file is part of GCC.

GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 3, or (at your option) any later
version.

GCC is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
for more details.

You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING3.  If not see
<http://www.gnu.org/licenses/>.   

This pass implements downward store motion.
As of May 1, 2009, the pass is not enabled by default on any target,
but bootstrap completes on ia64 and x86_64 with the pass enabled.   

TODO:
  - remove_reachable_equiv_notes is an incomprehensible pile of goo and
    a compile time hog that needs a rewrite (maybe cache st_exprs to
    invalidate REG_EQUAL/REG_EQUIV notes for?).
  - pattern_regs in st_expr should be a regset (on its own obstack).
  - store_motion_mems should be a vec instead of a list.
  - there should be an alloc pool for struct st_expr objects.
  - investigate whether it is helpful to make the address of an st_expr
    a cselib VALUE.
  - when GIMPLE alias information is exported, the effectiveness of this
    pass should be re-evaluated.

This is a list of store expressions (MEMs).  The structure is used
as an expression table to track stores which look interesting, and
might be moveable towards the exit block.   

Field Documentation

antic_stores

vec<rtx_insn *> st_expr::antic_stores

Referenced by build_store_vectors(), compute_store_table(), find_moveable_store(), free_st_expr_entry(), print_store_motion_mems(), remove_reachable_equiv_notes(), replace_store_insn(), and st_expr_entry().

avail_stores

vec<rtx_insn *> st_expr::avail_stores

Referenced by build_store_vectors(), compute_store_table(), find_moveable_store(), free_st_expr_entry(), print_store_motion_mems(), and st_expr_entry().

hash_index

unsigned int st_expr::hash_index

Referenced by compute_store_table(), and st_expr_entry().

index

int st_expr::index

Referenced by build_store_vectors(), enumerate_store_motion_mems(), insert_store(), one_store_motion_pass(), print_store_motion_mems(), remove_reachable_equiv_notes(), and st_expr_entry().

next

struct st_expr* st_expr::next

Referenced by compute_store_table(), enumerate_store_motion_mems(), free_store_motion_mems(), next_st_expr(), and st_expr_entry().

pattern

rtx st_expr::pattern

Referenced by build_store_vectors(), st_expr_hasher::equal(), st_expr_hasher::hash(), print_store_motion_mems(), remove_reachable_equiv_notes(), replace_store_insn(), and st_expr_entry().

pattern_regs

vec<rtx> st_expr::pattern_regs

Referenced by build_store_vectors(), find_moveable_store(), free_st_expr_entry(), and st_expr_entry().

reaching_reg

rtx st_expr::reaching_reg

Referenced by st_expr_entry().

---

The documentation for this struct was generated from the following file:

• store-motion.cc