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Commit a13d4ebf by Andrew MacLeod Committed by Andrew Macleod
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alias.c (get_addr): Externalize. 

2001-04-09  Andrew MacLeod  <amacleod@redhat.com>
	    Jeff Law  <law@cygnus.com>

	* alias.c (get_addr): Externalize.
	(canon_true_dependence): New function. Behaves like true_dependance
	except it already assumes a MEM has been canonicalized.
	* flags.h (flag_gcse_lm, flag_gcse_sm): New optimization flags.
	* gcse.c (struct ls_expr): Add load/store expressions structure.
	(modify_mem_list, canon_modify_mem_list): New variable.
	(gcse_main): Initialize & finalize alias analysis. Use enhanced
	load motion and store motion if requested.
	(alloc_gcse_mem): Allocate space for modify_mem_list array.
	(free_gcse_mem): Free the modify_mem_list array.
	(oprs_unchanged_p): Use load_killed_in_block_p.
	(gcse_mems_conflict_p, gcse_mem_operand): New variables.
	(mems_conflict_for_gcse_p): New function.  Don't kill loads
	with stores to themselves if its in the load/store expression list.
	(load_killed_in_block_p): New function.
	(canon_list_insert): New Function.
	(record_last_mem_set_info): Keep a list of all instructions which
	can modify memory for each basic block.
	(compute_hash_table, reset_opr_set_tables): Clear modify_mem_list.
	(oprs_not_set_p): Use load_killed_in_block_p.
	(mark_call, mark_set, mark_clobber): Use record_last_mem_set_info.
	(expr_killed_p): Use load_killed_in_block_p.
	(compute_transp): Do not pessimize memory references.
	(pre_edge_insert): Update stores for a load motion expression.
	(one_pre_gcse_pass): Check loads/stores for extra load motion.
	(ldst_entry): Find or create a ldst_expr structure.
	(free_ldst_entry): Free memory for an individual item.
	(free_ldst_mems): Free entire load/store expression list.
	(print_ldst_list): Print debug info.
	(find_rtx_in_ldst): Try to find an rtx expression in the ldst list.
	(enumerate_ldsts): Assign integer values to each entry in list.
	(first_ls_expr): First expression in the list.
	(next_ls_expr): Next expression in the list.
	(simple_mem): Check if expression qualifies for ld/st expression list.
	(invalidate_any_buried_refs): Remove from expression list if its
	used in some other way we dont understand.
	(compute_ld_motion_mems): Find all potential enhanced load motion
	expression.
	(trim_ld_motion_mems): Remove any expressions which are invalid.
	(update_ld_motion_stores): Copy store values to registers for loads
	which have been moved.
	(regvec, st_antloc, num_store): New global statics.
	(reg_set_info): Marks registers as set.
	(store_ops_ok): Verfies registers expressions are valid in a block.
	(find_moveable_store): Look for moveable stores in a pattern.
	(compute_store_table): Find stores in a function worth moving, maybe.
	(load_kills_store): Check dependance of a load and store.
	(find_loads): Find any loads in a pattern.
	(store_killed_in_insn): Check if a store is killed in an insn.
	(store_killed_after): Check is store killed after an insn in a block.
	(store_killed_before): Check is store killed before an insn in a block.
	(build_store_vectors): Generate the antic and avail vectors.
	(insert_insn_start_bb): Insert at the start of a BB, update BLOCK_HEAD.
	(insert_store): Add a store to an edge.
	(replace_store_insn): Replace a store with a SET insn.
	(delete_store): Delete a store insn.
	(free_store_memory): Free memory.
	(store_motion): Perform store motion.
	* invoke.texi: Add documentation for -fcse-lm and -fgcse-sm.
	* rtl.h (get_addr, canon_true_dependence): Add prototypes.
	* toplev.c (flag_gcse_lm, flag_gcse_sm): New Variables.
	(f_options): Add gcse-lm and gcse-sm.

Co-Authored-By: Jeff Law <law@redhat.com>

From-SVN: r41207
parent 92d0fb09
Showing with 1669 additions and 3 deletions
gcc/ChangeLog
2001-04-09 Andrew MacLeod <amacleod@redhat.com>
Jeff Law <law@redhat.com>
* alias.c (get_addr): Externalize.
(canon_true_dependence): New function. Behaves like true_dependance
except it already assumes a MEM has been canonicalized.
* flags.h (flag_gcse_lm, flag_gcse_sm): New optimization flags.
* gcse.c (struct ls_expr): Add load/store expressions structure.
(modify_mem_list, canon_modify_mem_list): New variable.
(gcse_main): Initialize & finalize alias analysis. Use enhanced
load motion and store motion if requested.
(alloc_gcse_mem): Allocate space for modify_mem_list array.
(free_gcse_mem): Free the modify_mem_list array.
(oprs_unchanged_p): Use load_killed_in_block_p.
(gcse_mems_conflict_p, gcse_mem_operand): New variables.
(mems_conflict_for_gcse_p): New function. Don't kill loads
with stores to themselves if its in the load/store expression list.
(load_killed_in_block_p): New function.
(canon_list_insert): New Function.
(record_last_mem_set_info): Keep a list of all instructions which
can modify memory for each basic block.
(compute_hash_table, reset_opr_set_tables): Clear modify_mem_list.
(oprs_not_set_p): Use load_killed_in_block_p.
(mark_call, mark_set, mark_clobber): Use record_last_mem_set_info.
(expr_killed_p): Use load_killed_in_block_p.
(compute_transp): Do not pessimize memory references.
(pre_edge_insert): Update stores for a load motion expression.
(one_pre_gcse_pass): Check loads/stores for extra load motion.
(ldst_entry): Find or create a ldst_expr structure.
(free_ldst_entry): Free memory for an individual item.
(free_ldst_mems): Free entire load/store expression list.
(print_ldst_list): Print debug info.
(find_rtx_in_ldst): Try to find an rtx expression in the ldst list.
(enumerate_ldsts): Assign integer values to each entry in list.
(first_ls_expr): First expression in the list.
(next_ls_expr): Next expression in the list.
(simple_mem): Check if expression qualifies for ld/st expression list.
(invalidate_any_buried_refs): Remove from expression list if its
used in some other way we dont understand.
(compute_ld_motion_mems): Find all potential enhanced load motion
expression.
(trim_ld_motion_mems): Remove any expressions which are invalid.
(update_ld_motion_stores): Copy store values to registers for loads
which have been moved.
(regvec, st_antloc, num_store): New global statics.
(reg_set_info): Marks registers as set.
(store_ops_ok): Verfies registers expressions are valid in a block.
(find_moveable_store): Look for moveable stores in a pattern.
(compute_store_table): Find stores in a function worth moving, maybe.
(load_kills_store): Check dependance of a load and store.
(find_loads): Find any loads in a pattern.
(store_killed_in_insn): Check if a store is killed in an insn.
(store_killed_after): Check is store killed after an insn in a block.
(store_killed_before): Check is store killed before an insn in a block.
(build_store_vectors): Generate the antic and avail vectors.
(insert_insn_start_bb): Insert at the start of a BB, update BLOCK_HEAD.
(insert_store): Add a store to an edge.
(replace_store_insn): Replace a store with a SET insn.
(delete_store): Delete a store insn.
(free_store_memory): Free memory.
(store_motion): Perform store motion.
* invoke.texi: Add documentation for -fcse-lm and -fgcse-sm.
* rtl.h (get_addr, canon_true_dependence): Add prototypes.
* toplev.c (flag_gcse_lm, flag_gcse_sm): New Variables.
(f_options): Add gcse-lm and gcse-sm.
Mon Apr 9 16:18:03 CEST 2001 Jan Hubicka <jh@suse.cz> Mon Apr 9 16:18:03 CEST 2001 Jan Hubicka <jh@suse.cz>
* i386.c (expand_fp_movcc): Fix condition reversal code. * i386.c (expand_fp_movcc): Fix condition reversal code.
......
gcc/alias.c
...@@ -87,7 +87,7 @@ typedef struct alias_set_entry ...@@ -87,7 +87,7 @@ typedef struct alias_set_entry
static int rtx_equal_for_memref_p PARAMS ((rtx, rtx)); static int rtx_equal_for_memref_p PARAMS ((rtx, rtx));
static rtx find_symbolic_term PARAMS ((rtx)); static rtx find_symbolic_term PARAMS ((rtx));
static rtx get_addr PARAMS ((rtx)); rtx get_addr PARAMS ((rtx));
static int memrefs_conflict_p PARAMS ((int, rtx, int, rtx, static int memrefs_conflict_p PARAMS ((int, rtx, int, rtx,
HOST_WIDE_INT)); HOST_WIDE_INT));
static void record_set PARAMS ((rtx, rtx, void *)); static void record_set PARAMS ((rtx, rtx, void *));
...@@ -1340,7 +1340,7 @@ base_alias_check (x, y, x_mode, y_mode) ...@@ -1340,7 +1340,7 @@ base_alias_check (x, y, x_mode, y_mode)
it unchanged unless it is a value; in the latter case we call cselib to get it unchanged unless it is a value; in the latter case we call cselib to get
a more useful rtx. */ a more useful rtx. */
static rtx rtx
get_addr (x) get_addr (x)
rtx x; rtx x;
{ {
...@@ -1765,6 +1765,63 @@ true_dependence (mem, mem_mode, x, varies) ...@@ -1765,6 +1765,63 @@ true_dependence (mem, mem_mode, x, varies)
varies); varies);
} }
/* Canonical true dependence: X is read after store in MEM takes place.
Variant of true_dependece which assumes MEM has already been
canonicalized (hence we no longer do that here).
The mem_addr argument has been added, since true_dependence computed
this value prior to canonicalizing. */
int
canon_true_dependence (mem, mem_mode, mem_addr, x, varies)
rtx mem, mem_addr, x;
enum machine_mode mem_mode;
int (*varies) PARAMS ((rtx, int));
{
register rtx x_addr;
if (MEM_VOLATILE_P (x) && MEM_VOLATILE_P (mem))
return 1;
if (DIFFERENT_ALIAS_SETS_P (x, mem))
return 0;
/* If X is an unchanging read, then it can't possibly conflict with any
non-unchanging store. It may conflict with an unchanging write though,
because there may be a single store to this address to initialize it.
Just fall through to the code below to resolve the case where we have
both an unchanging read and an unchanging write. This won't handle all
cases optimally, but the possible performance loss should be
negligible. */
if (RTX_UNCHANGING_P (x) && ! RTX_UNCHANGING_P (mem))
return 0;
x_addr = get_addr (XEXP (x, 0));
if (! base_alias_check (x_addr, mem_addr, GET_MODE (x), mem_mode))
return 0;
x_addr = canon_rtx (x_addr);
if (! memrefs_conflict_p (GET_MODE_SIZE (mem_mode), mem_addr,
SIZE_FOR_MODE (x), x_addr, 0))
return 0;
if (aliases_everything_p (x))
return 1;
/* We cannot use aliases_everyting_p to test MEM, since we must look
at MEM_MODE, rather than GET_MODE (MEM). */
if (mem_mode == QImode || GET_CODE (mem_addr) == AND)
return 1;
/* In true_dependence we also allow BLKmode to alias anything. Why
don't we do this in anti_dependence and output_dependence? */
if (mem_mode == BLKmode || GET_MODE (x) == BLKmode)
return 1;
return ! fixed_scalar_and_varying_struct_p (mem, x, mem_addr, x_addr,
varies);
}
/* Returns non-zero if a write to X might alias a previous read from /* Returns non-zero if a write to X might alias a previous read from
(or, if WRITEP is non-zero, a write to) MEM. */ (or, if WRITEP is non-zero, a write to) MEM. */
......
gcc/flags.h
...@@ -611,6 +611,15 @@ extern enum graph_dump_types graph_dump_format; ...@@ -611,6 +611,15 @@ extern enum graph_dump_types graph_dump_format;
extern int flag_no_ident; extern int flag_no_ident;
/* Nonzero if we want to perform enhanced load motion during gcse. */
extern int flag_gcse_lm;
/* Nonzero if we want to perform store motion after gcse. */
extern int flag_gcse_sm;
/* Nonzero means we should do dwarf2 duplicate elimination. */ /* Nonzero means we should do dwarf2 duplicate elimination. */
extern int flag_eliminate_dwarf2_dups; extern int flag_eliminate_dwarf2_dups;
......
gcc/gcse.c
...@@ -454,6 +454,33 @@ static int reg_set_table_size; ...@@ -454,6 +454,33 @@ static int reg_set_table_size;
/* Amount to grow `reg_set_table' by when it's full. */ /* Amount to grow `reg_set_table' by when it's full. */
#define REG_SET_TABLE_SLOP 100 #define REG_SET_TABLE_SLOP 100
/* This is a list of expressions which are MEMs and will be used by load
or store motion.
Load motion tracks MEMs which aren't killed by
anything except itself. (ie, loads and stores to a single location).
We can then allow movement of these MEM refs with a little special
allowance. (all stores copy the same value to the reaching reg used
for the loads). This means all values used to store into memory must have
no side effects so we can re-issue the setter value.
Store Motion uses this structure as an expression table to track stores
which look interesting, and might be moveable towards the exit block. */
struct ls_expr
{
struct expr * expr; /* Gcse expression reference for LM. */
rtx pattern; /* Pattern of this mem. */
rtx loads; /* INSN list of loads seen. */
rtx stores; /* INSN list of stores seen. */
struct ls_expr * next; /* Next in the list. */
int invalid; /* Invalid for some reason. */
int index; /* If it maps to a bitmap index. */
int hash_index; /* Index when in a hash table. */
rtx reaching_reg; /* Register to use when re-writing. */
};
/* Head of the list of load/store memory refs. */
static struct ls_expr * pre_ldst_mems = NULL;
/* Bitmap containing one bit for each register in the program. /* Bitmap containing one bit for each register in the program.
Used when performing GCSE to track which registers have been set since Used when performing GCSE to track which registers have been set since
the start of the basic block. */ the start of the basic block. */
...@@ -466,6 +493,13 @@ static sbitmap reg_set_bitmap; ...@@ -466,6 +493,13 @@ static sbitmap reg_set_bitmap;
gcse) and it's currently not easy to realloc sbitmap vectors. */ gcse) and it's currently not easy to realloc sbitmap vectors. */
static sbitmap *reg_set_in_block; static sbitmap *reg_set_in_block;
/* Array, indexed by basic block number for a list of insns which modify
memory within that block. */
static rtx * modify_mem_list;
/* This array parallels modify_mem_list, but is kept canonicalized. */
static rtx * canon_modify_mem_list;
/* For each block, non-zero if memory is set in that block. /* For each block, non-zero if memory is set in that block.
This is computed during hash table computation and is used by This is computed during hash table computation and is used by
expr_killed_p and compute_transp. expr_killed_p and compute_transp.
...@@ -588,6 +622,9 @@ static int cprop_jump PARAMS ((rtx, rtx, rtx)); ...@@ -588,6 +622,9 @@ static int cprop_jump PARAMS ((rtx, rtx, rtx));
#ifdef HAVE_cc0 #ifdef HAVE_cc0
static int cprop_cc0_jump PARAMS ((rtx, struct reg_use *, rtx)); static int cprop_cc0_jump PARAMS ((rtx, struct reg_use *, rtx));
#endif #endif
static void mems_conflict_for_gcse_p PARAMS ((rtx, rtx, void *));
static int load_killed_in_block_p PARAMS ((int, int, rtx, int));
static void canon_list_insert PARAMS ((rtx, rtx, void *));
static int cprop_insn PARAMS ((rtx, int)); static int cprop_insn PARAMS ((rtx, int));
static int cprop PARAMS ((int)); static int cprop PARAMS ((int));
static int one_cprop_pass PARAMS ((int, int)); static int one_cprop_pass PARAMS ((int, int));
...@@ -637,6 +674,35 @@ static int expr_reaches_here_p_work PARAMS ((struct occr *, struct expr *, ...@@ -637,6 +674,35 @@ static int expr_reaches_here_p_work PARAMS ((struct occr *, struct expr *,
int, int, char *)); int, int, char *));
static int pre_expr_reaches_here_p_work PARAMS ((int, struct expr *, static int pre_expr_reaches_here_p_work PARAMS ((int, struct expr *,
int, char *)); int, char *));
static struct ls_expr * ldst_entry PARAMS ((rtx));
static void free_ldst_entry PARAMS ((struct ls_expr *));
static void free_ldst_mems PARAMS ((void));
static void print_ldst_list PARAMS ((FILE *));
static struct ls_expr * find_rtx_in_ldst PARAMS ((rtx));
static int enumerate_ldsts PARAMS ((void));
static inline struct ls_expr * first_ls_expr PARAMS ((void));
static inline struct ls_expr * next_ls_expr PARAMS ((struct ls_expr *));
static int simple_mem PARAMS ((rtx));
static void invalidate_any_buried_refs PARAMS ((rtx));
static void compute_ld_motion_mems PARAMS ((void));
static void trim_ld_motion_mems PARAMS ((void));
static void update_ld_motion_stores PARAMS ((struct expr *));
static void reg_set_info PARAMS ((rtx, rtx, void *));
static int store_ops_ok PARAMS ((rtx, int));
static void find_moveable_store PARAMS ((rtx));
static int compute_store_table PARAMS ((void));
static int load_kills_store PARAMS ((rtx, rtx));
static int find_loads PARAMS ((rtx, rtx));
static int store_killed_in_insn PARAMS ((rtx, rtx));
static int store_killed_after PARAMS ((rtx, rtx, int));
static int store_killed_before PARAMS ((rtx, rtx, int));
static void build_store_vectors PARAMS ((void));
static void insert_insn_start_bb PARAMS ((rtx, int));
static int insert_store PARAMS ((struct ls_expr *, edge));
static void replace_store_insn PARAMS ((rtx, rtx, int));
static void delete_store PARAMS ((struct ls_expr *, int));
static void free_store_memory PARAMS ((void));
static void store_motion PARAMS ((void));
/* Entry point for global common subexpression elimination. /* Entry point for global common subexpression elimination.
F is the first instruction in the function. */ F is the first instruction in the function. */
...@@ -654,6 +720,10 @@ gcse_main (f, file) ...@@ -654,6 +720,10 @@ gcse_main (f, file)
/* Point to release obstack data from for each pass. */ /* Point to release obstack data from for each pass. */
char *gcse_obstack_bottom; char *gcse_obstack_bottom;
/* Insertion of instructions on edges can create new basic blocks; we
need the original basic block count so that we can properly deallocate
arrays sized on the number of basic blocks originally in the cfg. */
int orig_bb_count;
/* We do not construct an accurate cfg in functions which call /* We do not construct an accurate cfg in functions which call
setjmp, so just punt to be safe. */ setjmp, so just punt to be safe. */
if (current_function_calls_setjmp) if (current_function_calls_setjmp)
...@@ -673,6 +743,7 @@ gcse_main (f, file) ...@@ -673,6 +743,7 @@ gcse_main (f, file)
if (file) if (file)
dump_flow_info (file); dump_flow_info (file);
orig_bb_count = n_basic_blocks;
/* Return if there's nothing to do. */ /* Return if there's nothing to do. */
if (n_basic_blocks <= 1) if (n_basic_blocks <= 1)
return 0; return 0;
...@@ -703,6 +774,8 @@ gcse_main (f, file) ...@@ -703,6 +774,8 @@ gcse_main (f, file)
gcc_obstack_init (&gcse_obstack); gcc_obstack_init (&gcse_obstack);
bytes_used = 0; bytes_used = 0;
/* We need alias. */
init_alias_analysis ();
/* Record where pseudo-registers are set. This data is kept accurate /* Record where pseudo-registers are set. This data is kept accurate
during each pass. ??? We could also record hard-reg information here during each pass. ??? We could also record hard-reg information here
[since it's unchanging], however it is currently done during hash table [since it's unchanging], however it is currently done during hash table
...@@ -744,6 +817,28 @@ gcse_main (f, file) ...@@ -744,6 +817,28 @@ gcse_main (f, file)
else else
{ {
changed |= one_pre_gcse_pass (pass + 1); changed |= one_pre_gcse_pass (pass + 1);
/* We may have just created new basic blocks. Release and
recompute various things which are sized on the number of
basic blocks. */
if (changed)
{
int i;
for (i = 0; i < orig_bb_count; i++)
{
if (modify_mem_list[i])
free_INSN_LIST_list (modify_mem_list + i);
if (canon_modify_mem_list[i])
free_INSN_LIST_list (canon_modify_mem_list + i);
}
modify_mem_list
= (rtx *) gmalloc (n_basic_blocks * sizeof (rtx *));
canon_modify_mem_list
= (rtx *) gmalloc (n_basic_blocks * sizeof (rtx *));
memset ((char *) modify_mem_list, 0, n_basic_blocks * sizeof (rtx *));
memset ((char *) canon_modify_mem_list, 0, n_basic_blocks * sizeof (rtx *));
orig_bb_count = n_basic_blocks;
}
free_reg_set_mem (); free_reg_set_mem ();
alloc_reg_set_mem (max_reg_num ()); alloc_reg_set_mem (max_reg_num ());
compute_sets (f); compute_sets (f);
...@@ -804,6 +899,13 @@ gcse_main (f, file) ...@@ -804,6 +899,13 @@ gcse_main (f, file)
obstack_free (&gcse_obstack, NULL_PTR); obstack_free (&gcse_obstack, NULL_PTR);
free_reg_set_mem (); free_reg_set_mem ();
/* We are finished with alias. */
end_alias_analysis ();
allocate_reg_info (max_reg_num (), FALSE, FALSE);
if (!optimize_size && flag_gcse_sm)
store_motion ();
/* Record where pseudo-registers are set. */
return run_jump_opt_after_gcse; return run_jump_opt_after_gcse;
} }
...@@ -917,6 +1019,12 @@ alloc_gcse_mem (f) ...@@ -917,6 +1019,12 @@ alloc_gcse_mem (f)
reg_set_in_block = (sbitmap *) sbitmap_vector_alloc (n_basic_blocks, reg_set_in_block = (sbitmap *) sbitmap_vector_alloc (n_basic_blocks,
max_gcse_regno); max_gcse_regno);
mem_set_in_block = (char *) gmalloc (n_basic_blocks); mem_set_in_block = (char *) gmalloc (n_basic_blocks);
/* Allocate array to keep a list of insns which modify memory in each
basic block. */
modify_mem_list = (rtx *) gmalloc (n_basic_blocks * sizeof (rtx *));
canon_modify_mem_list = (rtx *) gmalloc (n_basic_blocks * sizeof (rtx *));
memset ((char *) modify_mem_list, 0, n_basic_blocks * sizeof (rtx *));
memset ((char *) canon_modify_mem_list, 0, n_basic_blocks * sizeof (rtx *));
} }
/* Free memory allocated by alloc_gcse_mem. */ /* Free memory allocated by alloc_gcse_mem. */
...@@ -931,6 +1039,23 @@ free_gcse_mem () ...@@ -931,6 +1039,23 @@ free_gcse_mem ()
free (reg_set_in_block); free (reg_set_in_block);
free (mem_set_in_block); free (mem_set_in_block);
/* re-Cache any INSN_LIST nodes we have allocated. */
{
int i;
for (i = 0; i < n_basic_blocks; i++)
{
if (modify_mem_list[i])
free_INSN_LIST_list (modify_mem_list + i);
if (canon_modify_mem_list[i])
free_INSN_LIST_list (canon_modify_mem_list + i);
}
free (modify_mem_list);
free (canon_modify_mem_list);
modify_mem_list = 0;
canon_modify_mem_list = 0;
}
} }
/* Many of the global optimization algorithms work by solving dataflow /* Many of the global optimization algorithms work by solving dataflow
...@@ -1267,6 +1392,9 @@ oprs_unchanged_p (x, insn, avail_p) ...@@ -1267,6 +1392,9 @@ oprs_unchanged_p (x, insn, avail_p)
|| reg_first_set[REGNO (x)] >= INSN_CUID (insn)); || reg_first_set[REGNO (x)] >= INSN_CUID (insn));
case MEM: case MEM:
if (load_killed_in_block_p (BLOCK_NUM (insn), INSN_CUID (insn),
x, avail_p))
return 0;
if (avail_p && mem_last_set != NEVER_SET if (avail_p && mem_last_set != NEVER_SET
&& mem_last_set >= INSN_CUID (insn)) && mem_last_set >= INSN_CUID (insn))
return 0; return 0;
...@@ -1321,6 +1449,105 @@ oprs_unchanged_p (x, insn, avail_p) ...@@ -1321,6 +1449,105 @@ oprs_unchanged_p (x, insn, avail_p)
return 1; return 1;
} }
/* Used for communication between mems_conflict_for_gcse_p and
load_killed_in_block_p. Nonzero if mems_conflict_for_gcse_p finds a
conflict between two memory references. */
static int gcse_mems_conflict_p;
/* Used for communication between mems_conflict_for_gcse_p and
load_killed_in_block_p. A memory reference for a load instruction,
mems_conflict_for_gcse_p will see if a memory store conflicts with
this memory load. */
static rtx gcse_mem_operand;
/* DEST is the output of an instruction. If it is a memory reference, and
possibly conflicts with the load found in gcse_mem_operand, then set
gcse_mems_conflict_p to a nonzero value. */
static void
mems_conflict_for_gcse_p (dest, setter, data)
rtx dest, setter ATTRIBUTE_UNUSED;
void *data ATTRIBUTE_UNUSED;
{
while (GET_CODE (dest) == SUBREG
|| GET_CODE (dest) == ZERO_EXTRACT
|| GET_CODE (dest) == SIGN_EXTRACT
|| GET_CODE (dest) == STRICT_LOW_PART)
dest = XEXP (dest, 0);
/* If DEST is not a MEM, then it will not conflict with the load. Note
that function calls are assumed to clobber memory, but are handled
elsewhere. */
if (GET_CODE (dest) != MEM)
return;
/* If we are setting a MEM in our list of specially recognized MEMs,
don't mark as killed this time. */
if (dest == gcse_mem_operand && pre_ldst_mems != NULL)
{
if (!find_rtx_in_ldst (dest))
gcse_mems_conflict_p = 1;
return;
}
if (true_dependence (dest, GET_MODE (dest), gcse_mem_operand,
rtx_addr_varies_p))
gcse_mems_conflict_p = 1;
}
/* Return nonzero if the expression in X (a memory reference) is killed
in block BB before or after the insn with the CUID in UID_LIMIT.
AVAIL_P is nonzero for kills after UID_LIMIT, and zero for kills
before UID_LIMIT.
To check the entire block, set UID_LIMIT to max_uid + 1 and
AVAIL_P to 0. */
static int
load_killed_in_block_p (bb, uid_limit, x, avail_p)
int bb;
int uid_limit;
rtx x;
int avail_p;
{
rtx list_entry = modify_mem_list[bb];
while (list_entry)
{
rtx setter;
/* Ignore entries in the list that do not apply. */
if ((avail_p
&& INSN_CUID (XEXP (list_entry, 0)) < uid_limit)
|| (! avail_p
&& INSN_CUID (XEXP (list_entry, 0)) > uid_limit))
{
list_entry = XEXP (list_entry, 1);
continue;
}
setter = XEXP (list_entry, 0);
/* If SETTER is a call everything is clobbered. Note that calls
to pure functions are never put on the list, so we need not
worry about them. */
if (GET_CODE (setter) == CALL_INSN)
return 1;
/* SETTER must be an INSN of some kind that sets memory. Call
note_stores to examine each hunk of memory that is modified.
The note_stores interface is pretty limited, so we have to
communicate via global variables. Yuk. */
gcse_mem_operand = x;
gcse_mems_conflict_p = 0;
note_stores (PATTERN (setter), mems_conflict_for_gcse_p, NULL);
if (gcse_mems_conflict_p)
return 1;
list_entry = XEXP (list_entry, 1);
}
return 0;
}
/* Return non-zero if the operands of expression X are unchanged from /* Return non-zero if the operands of expression X are unchanged from
the start of INSN's basic block up to but not including INSN. */ the start of INSN's basic block up to but not including INSN. */
...@@ -2126,7 +2353,46 @@ record_last_reg_set_info (insn, regno) ...@@ -2126,7 +2353,46 @@ record_last_reg_set_info (insn, regno)
SET_BIT (reg_set_in_block[BLOCK_NUM (insn)], regno); SET_BIT (reg_set_in_block[BLOCK_NUM (insn)], regno);
} }
/* Record all of the canonicalized MEMs of record_last_mem_set_info's insn.
Note we store a pair of elements in the list, so they have to be
taken off pairwise. */
static void
canon_list_insert (dest, unused1, v_insn)
rtx dest ATTRIBUTE_UNUSED;
rtx unused1 ATTRIBUTE_UNUSED;
void * v_insn;
{
rtx dest_addr, insn;
while (GET_CODE (dest) == SUBREG
|| GET_CODE (dest) == ZERO_EXTRACT
|| GET_CODE (dest) == SIGN_EXTRACT
|| GET_CODE (dest) == STRICT_LOW_PART)
dest = XEXP (dest, 0);
/* If DEST is not a MEM, then it will not conflict with a load. Note
that function calls are assumed to clobber memory, but are handled
elsewhere. */
if (GET_CODE (dest) != MEM)
return;
dest_addr = get_addr (XEXP (dest, 0));
dest_addr = canon_rtx (dest_addr);
insn = (rtx) v_insn;
canon_modify_mem_list[BLOCK_NUM (insn)] =
alloc_INSN_LIST (dest_addr, canon_modify_mem_list[BLOCK_NUM (insn)]);
canon_modify_mem_list[BLOCK_NUM (insn)] =
alloc_INSN_LIST (dest, canon_modify_mem_list[BLOCK_NUM (insn)]);
}
/* Record memory first/last/block set information for INSN. */ /* Record memory first/last/block set information for INSN. */
/* Record memory modification information for INSN. We do not actually care
about the memory location(s) that are set, or even how they are set (consider
a CALL_INSN). We merely need to record which insns modify memory. */
static void static void
record_last_mem_set_info (insn) record_last_mem_set_info (insn)
...@@ -2137,6 +2403,19 @@ record_last_mem_set_info (insn) ...@@ -2137,6 +2403,19 @@ record_last_mem_set_info (insn)
mem_last_set = INSN_CUID (insn); mem_last_set = INSN_CUID (insn);
mem_set_in_block[BLOCK_NUM (insn)] = 1; mem_set_in_block[BLOCK_NUM (insn)] = 1;
modify_mem_list[BLOCK_NUM (insn)] =
alloc_INSN_LIST (insn, modify_mem_list[BLOCK_NUM (insn)]);
if (GET_CODE (insn) == CALL_INSN)
{
/* Note that traversals of this loop (other than for free-ing)
will break after encountering a CALL_INSN. So, there's no
need to insert a pair of items, as canon_list_insert does. */
canon_modify_mem_list[BLOCK_NUM (insn)] =
alloc_INSN_LIST (insn, canon_modify_mem_list[BLOCK_NUM (insn)]);
}
else
note_stores (PATTERN (insn), canon_list_insert, (void*)insn );
} }
/* Called from compute_hash_table via note_stores to handle one /* Called from compute_hash_table via note_stores to handle one
...@@ -2193,6 +2472,17 @@ compute_hash_table (set_p) ...@@ -2193,6 +2472,17 @@ compute_hash_table (set_p)
sbitmap_vector_zero (reg_set_in_block, n_basic_blocks); sbitmap_vector_zero (reg_set_in_block, n_basic_blocks);
memset ((char *) mem_set_in_block, 0, n_basic_blocks); memset ((char *) mem_set_in_block, 0, n_basic_blocks);
/* re-Cache any INSN_LIST nodes we have allocated. */
{
int i;
for (i = 0; i < n_basic_blocks; i++)
{
if (modify_mem_list[i])
free_INSN_LIST_list (modify_mem_list + i);
if (canon_modify_mem_list[i])
free_INSN_LIST_list (canon_modify_mem_list + i);
}
}
/* Some working arrays used to track first and last set in each block. */ /* Some working arrays used to track first and last set in each block. */
/* ??? One could use alloca here, but at some size a threshold is crossed /* ??? One could use alloca here, but at some size a threshold is crossed
beyond which one should use malloc. Are we at that threshold here? */ beyond which one should use malloc. Are we at that threshold here? */
...@@ -2450,6 +2740,18 @@ reset_opr_set_tables () ...@@ -2450,6 +2740,18 @@ reset_opr_set_tables ()
For now this is very trivial, we only record whether any memory For now this is very trivial, we only record whether any memory
location has been modified. */ location has been modified. */
mem_last_set = 0; mem_last_set = 0;
{
int i;
/* re-Cache any INSN_LIST nodes we have allocated. */
for (i = 0; i < n_basic_blocks; i++)
{
if (modify_mem_list[i])
free_INSN_LIST_list (modify_mem_list + i);
if (canon_modify_mem_list[i])
free_INSN_LIST_list (canon_modify_mem_list + i);
}
}
} }
/* Return non-zero if the operands of X are not set before INSN in /* Return non-zero if the operands of X are not set before INSN in
...@@ -2481,6 +2783,8 @@ oprs_not_set_p (x, insn) ...@@ -2481,6 +2783,8 @@ oprs_not_set_p (x, insn)
return 1; return 1;
case MEM: case MEM:
if (load_killed_in_block_p (BLOCK_NUM (insn), INSN_CUID (insn), x, 0))
return 0;
if (mem_last_set != 0) if (mem_last_set != 0)
return 0; return 0;
else else
...@@ -2522,6 +2826,8 @@ mark_call (insn) ...@@ -2522,6 +2826,8 @@ mark_call (insn)
rtx insn; rtx insn;
{ {
mem_last_set = INSN_CUID (insn); mem_last_set = INSN_CUID (insn);
if (! CONST_CALL_P (insn))
record_last_mem_set_info (insn);
} }
/* Mark things set by a SET. */ /* Mark things set by a SET. */
...@@ -2541,6 +2847,11 @@ mark_set (pat, insn) ...@@ -2541,6 +2847,11 @@ mark_set (pat, insn)
if (GET_CODE (dest) == REG) if (GET_CODE (dest) == REG)
SET_BIT (reg_set_bitmap, REGNO (dest)); SET_BIT (reg_set_bitmap, REGNO (dest));
else if (GET_CODE (dest) == MEM) else if (GET_CODE (dest) == MEM)
record_last_mem_set_info (insn);
if (GET_CODE (dest) == REG)
SET_BIT (reg_set_bitmap, REGNO (dest));
else if (GET_CODE (dest) == MEM)
mem_last_set = INSN_CUID (insn); mem_last_set = INSN_CUID (insn);
if (GET_CODE (SET_SRC (pat)) == CALL) if (GET_CODE (SET_SRC (pat)) == CALL)
...@@ -2562,6 +2873,10 @@ mark_clobber (pat, insn) ...@@ -2562,6 +2873,10 @@ mark_clobber (pat, insn)
SET_BIT (reg_set_bitmap, REGNO (clob)); SET_BIT (reg_set_bitmap, REGNO (clob));
else else
mem_last_set = INSN_CUID (insn); mem_last_set = INSN_CUID (insn);
if (GET_CODE (clob) == REG)
SET_BIT (reg_set_bitmap, REGNO (clob));
else
record_last_mem_set_info (insn);
} }
/* Record things set by INSN. /* Record things set by INSN.
...@@ -2809,6 +3124,8 @@ expr_killed_p (x, bb) ...@@ -2809,6 +3124,8 @@ expr_killed_p (x, bb)
return TEST_BIT (reg_set_in_block[bb], REGNO (x)); return TEST_BIT (reg_set_in_block[bb], REGNO (x));
case MEM: case MEM:
if (load_killed_in_block_p (bb, get_max_uid () + 1, x, 0))
return 1;
if (mem_set_in_block[bb]) if (mem_set_in_block[bb])
return 1; return 1;
else else
...@@ -3476,6 +3793,41 @@ compute_transp (x, indx, bmap, set_p) ...@@ -3476,6 +3793,41 @@ compute_transp (x, indx, bmap, set_p)
return; return;
case MEM: case MEM:
for (bb = 0; bb < n_basic_blocks; bb++)
{
rtx list_entry = canon_modify_mem_list[bb];
while (list_entry)
{
rtx dest, dest_addr;
if (GET_CODE (XEXP (list_entry, 0)) == CALL_INSN)
{
if (set_p)
SET_BIT (bmap[bb], indx);
else
RESET_BIT (bmap[bb], indx);
break;
}
/* LIST_ENTRY must be an INSN of some kind that sets memory.
Examine each hunk of memory that is modified. */
dest = XEXP (list_entry, 0);
list_entry = XEXP (list_entry, 1);
dest_addr = XEXP (list_entry, 0);
if (canon_true_dependence (dest, GET_MODE (dest), dest_addr,
x, rtx_addr_varies_p))
{
if (set_p)
SET_BIT (bmap[bb], indx);
else
RESET_BIT (bmap[bb], indx);
break;
}
list_entry = XEXP (list_entry, 1);
}
}
if (set_p) if (set_p)
{ {
for (bb = 0; bb < n_basic_blocks; bb++) for (bb = 0; bb < n_basic_blocks; bb++)
...@@ -4555,6 +4907,7 @@ pre_edge_insert (edge_list, index_map) ...@@ -4555,6 +4907,7 @@ pre_edge_insert (edge_list, index_map)
expr->bitmap_index); expr->bitmap_index);
} }
update_ld_motion_stores (expr);
SET_BIT (inserted[e], j); SET_BIT (inserted[e], j);
did_insert = 1; did_insert = 1;
gcse_create_count++; gcse_create_count++;
...@@ -4815,7 +5168,11 @@ one_pre_gcse_pass (pass) ...@@ -4815,7 +5168,11 @@ one_pre_gcse_pass (pass)
alloc_expr_hash_table (max_cuid); alloc_expr_hash_table (max_cuid);
add_noreturn_fake_exit_edges (); add_noreturn_fake_exit_edges ();
if (flag_gcse_lm)
compute_ld_motion_mems ();
compute_expr_hash_table (); compute_expr_hash_table ();
trim_ld_motion_mems ();
if (gcse_file) if (gcse_file)
dump_hash_table (gcse_file, "Expression", expr_hash_table, dump_hash_table (gcse_file, "Expression", expr_hash_table,
expr_hash_table_size, n_exprs); expr_hash_table_size, n_exprs);
...@@ -4829,6 +5186,7 @@ one_pre_gcse_pass (pass) ...@@ -4829,6 +5186,7 @@ one_pre_gcse_pass (pass)
free_pre_mem (); free_pre_mem ();
} }
free_ldst_mems ();
remove_fake_edges (); remove_fake_edges ();
free_expr_hash_table (); free_expr_hash_table ();
...@@ -5603,3 +5961,1148 @@ one_code_hoisting_pass () ...@@ -5603,3 +5961,1148 @@ one_code_hoisting_pass ()
return changed; return changed;
} }
/* Here we provide the things required to do store motion towards
the exit. In order for this to be effective, gcse also needed to
be taught how to move a load when it is kill only by a store to itself.
int i;
float a[10];
void foo(float scale)
{
for (i=0; i<10; i++)
a[i] *= scale;
}
'i' is both loaded and stored to in the loop. Normally, gcse cannot move
the load out since its live around the loop, and stored at the bottom
of the loop.
The 'Load Motion' referred to and implemented in this file is
an enhancement to gcse which when using edge based lcm, recognizes
this situation and allows gcse to move the load out of the loop.
Once gcse has hoisted the load, store motion can then push this
load towards the exit, and we end up with no loads or stores of 'i'
in the loop. */
/* This will search the ldst list for a matching expresion. If it
doesn't find one, we create one and initialize it. */
static struct ls_expr *
ldst_entry (x)
rtx x;
{
struct ls_expr * ptr;
for (ptr = first_ls_expr(); ptr != NULL; ptr = next_ls_expr (ptr))
if (expr_equiv_p (ptr->pattern, x))
break;
if (!ptr)
{
ptr = (struct ls_expr *) xmalloc (sizeof (struct ls_expr));
ptr->next = pre_ldst_mems;
ptr->expr = NULL;
ptr->pattern = x;
ptr->loads = NULL_RTX;
ptr->stores = NULL_RTX;
ptr->reaching_reg = NULL_RTX;
ptr->invalid = 0;
ptr->index = 0;
ptr->hash_index = 0;
pre_ldst_mems = ptr;
}
return ptr;
}
/* Free up an individual ldst entry. */
static void
free_ldst_entry (ptr)
struct ls_expr * ptr;
{
free_INSN_LIST_list (& ptr->loads);
free_INSN_LIST_list (& ptr->stores);
free (ptr);
}
/* Free up all memory associated with the ldst list. */
static void
free_ldst_mems ()
{
while (pre_ldst_mems)
{
struct ls_expr * tmp = pre_ldst_mems;
pre_ldst_mems = pre_ldst_mems->next;
free_ldst_entry (tmp);
}
pre_ldst_mems = NULL;
}
/* Dump debugging info about the ldst list. */
static void
print_ldst_list (file)
FILE * file;
{
struct ls_expr * ptr;
fprintf (file, "LDST list: \n");
for (ptr = first_ls_expr(); ptr != NULL; ptr = next_ls_expr (ptr))
{
fprintf (file, " Pattern (%3d): ", ptr->index);
print_rtl (file, ptr->pattern);
fprintf (file, "\n Loads : ");
if (ptr->loads)
print_rtl (file, ptr->loads);
else
fprintf (file, "(nil)");
fprintf (file, "\n Stores : ");
if (ptr->stores)
print_rtl (file, ptr->stores);
else
fprintf (file, "(nil)");
fprintf (file, "\n\n");
}
fprintf (file, "\n");
}
/* Returns 1 if X is in the list of ldst only expressions. */
static struct ls_expr *
find_rtx_in_ldst (x)
rtx x;
{
struct ls_expr * ptr;
for (ptr = pre_ldst_mems; ptr != NULL; ptr = ptr->next)
if (expr_equiv_p (ptr->pattern, x) && ! ptr->invalid)
return ptr;
return NULL;
}
/* Assign each element of the list of mems a monotonically increasing value. */
static int
enumerate_ldsts ()
{
struct ls_expr * ptr;
int n = 0;
for (ptr = pre_ldst_mems; ptr != NULL; ptr = ptr->next)
ptr->index = n++;
return n;
}
/* Return first item in the list. */
static inline struct ls_expr *
first_ls_expr ()
{
return pre_ldst_mems;
}
/* Return the next item in ther list after the specified one. */
static inline struct ls_expr *
next_ls_expr (ptr)
struct ls_expr * ptr;
{
return ptr->next;
}
/* Load Motion for loads which only kill themselves. */
/* Return true if x is a simple MEM operation, with no registers or
side effects. These are the types of loads we consider for the
ld_motion list, otherwise we let the usual aliasing take care of it. */
static int
simple_mem (x)
rtx x;
{
if (GET_CODE (x) != MEM)
return 0;
if (MEM_VOLATILE_P (x))
return 0;
if (GET_MODE (x) == BLKmode)
return 0;
if (!rtx_varies_p (XEXP (x, 0), 0))
return 1;
return 0;
}
/* Make sure there isn't a buried reference in this pattern anywhere.
If there is, invalidate the entry for it since we're not capable
of fixing it up just yet.. We have to be sure we know about ALL
loads since the aliasing code will allow all entries in the
ld_motion list to not-alias itself. If we miss a load, we will get
the wrong value since gcse might common it and we won't know to
fix it up. */
static void
invalidate_any_buried_refs (x)
rtx x;
{
const char * fmt;
int i,j;
struct ls_expr * ptr;
/* Invalidate it in the list. */
if (GET_CODE (x) == MEM && simple_mem (x))
{
ptr = ldst_entry (x);
ptr->invalid = 1;
}
/* Recursively process the insn. */
fmt = GET_RTX_FORMAT (GET_CODE (x));
for (i = GET_RTX_LENGTH (GET_CODE (x)) - 1; i >= 0; i--)
{
if (fmt[i] == 'e')
invalidate_any_buried_refs (XEXP (x, i));
else if (fmt[i] == 'E')
for (j = XVECLEN (x, i) - 1; j >= 0; j--)
invalidate_any_buried_refs (XVECEXP (x, i, j));
}
}
/* Find all the 'simple' MEMs which are used in LOADs and STORES. Simple
being defined as MEM loads and stores to symbols, with no
side effects and no registers in the expression. If there are any
uses/defs which dont match this criteria, it is invalidated and
trimmed out later. */
static void
compute_ld_motion_mems ()
{
struct ls_expr * ptr;
int bb;
rtx insn;
pre_ldst_mems = NULL;
for (bb = 0; bb < n_basic_blocks; bb++)
{
for (insn = BLOCK_HEAD (bb);
insn && insn != NEXT_INSN (BLOCK_END (bb));
insn = NEXT_INSN (insn))
{
if (GET_RTX_CLASS (GET_CODE (insn)) == 'i')
{
if (GET_CODE (PATTERN (insn)) == SET)
{
rtx src = SET_SRC (PATTERN (insn));
rtx dest = SET_DEST (PATTERN (insn));
/* Check for a simple LOAD... */
if (GET_CODE (src) == MEM && simple_mem (src))
{
ptr = ldst_entry (src);
if (GET_CODE (dest) == REG)
ptr->loads = alloc_INSN_LIST (insn, ptr->loads);
else
ptr->invalid = 1;
}
else
{
/* Make sure there isn't a buried load somewhere. */
invalidate_any_buried_refs (src);
}
/* Check for stores. Don't worry about aliased ones, they
will block any movement we might do later. We only care
about this exact pattern since those are the only
circumstance that we will ignore the aliasing info. */
if (GET_CODE (dest) == MEM && simple_mem (dest))
{
ptr = ldst_entry (dest);
if (GET_CODE (src) != MEM)
ptr->stores = alloc_INSN_LIST (insn, ptr->stores);
else
ptr->invalid = 1;
}
}
else
invalidate_any_buried_refs (PATTERN (insn));
}
}
}
}
/* Remove any references that have been either invalidated or are not in the
expression list for pre gcse. */
static void
trim_ld_motion_mems ()
{
struct ls_expr * last = NULL;
struct ls_expr * ptr = first_ls_expr ();
while (ptr != NULL)
{
int del = ptr->invalid;
struct expr * expr = NULL;
/* Delete if entry has been made invalid. */
if (!del)
{
unsigned int i;
del = 1;
/* Delete if we cannot find this mem in the expression list. */
for (i = 0; i < expr_hash_table_size && del; i++)
{
for (expr = expr_hash_table[i];
expr != NULL;
expr = expr->next_same_hash)
if (expr_equiv_p (expr->expr, ptr->pattern))
{
del = 0;
break;
}
}
}
if (del)
{
if (last != NULL)
{
last->next = ptr->next;
free_ldst_entry (ptr);
ptr = last->next;
}
else
{
pre_ldst_mems = pre_ldst_mems->next;
free_ldst_entry (ptr);
ptr = pre_ldst_mems;
}
}
else
{
/* Set the expression field if we are keeping it. */
last = ptr;
ptr->expr = expr;
ptr = ptr->next;
}
}
/* Show the world what we've found. */
if (gcse_file && pre_ldst_mems != NULL)
print_ldst_list (gcse_file);
}
/* This routine will take an expression which we are replacing with
a reaching register, and update any stores that are needed if
that expression is in the ld_motion list. Stores are updated by
copying their SRC to the reaching register, and then storeing
the reaching register into the store location. These keeps the
correct value in the reaching register for the loads. */
static void
update_ld_motion_stores (expr)
struct expr * expr;
{
struct ls_expr * mem_ptr;
if ((mem_ptr = find_rtx_in_ldst (expr->expr)))
{
/* We can try to find just the REACHED stores, but is shouldn't
matter to set the reaching reg everywhere... some might be
dead and should be eliminated later. */
/* We replace SET mem = expr with
SET reg = expr
SET mem = reg , where reg is the
reaching reg used in the load. */
rtx list = mem_ptr->stores;
for ( ; list != NULL_RTX; list = XEXP (list, 1))
{
rtx insn = XEXP (list, 0);
rtx pat = PATTERN (insn);
rtx src = SET_SRC (pat);
rtx reg = expr->reaching_reg;
rtx copy, i;
/* If we've already copied it, continue. */
if (expr->reaching_reg == src)
continue;
if (gcse_file)
{
fprintf (gcse_file, "PRE: store updated with reaching reg ");
print_rtl (gcse_file, expr->reaching_reg);
fprintf (gcse_file, ":\n ");
print_inline_rtx (gcse_file, insn, 8);
fprintf (gcse_file, "\n");
}
copy = gen_move_insn ( reg, SET_SRC (pat));
i = emit_insn_before (copy, insn);
record_one_set (REGNO (reg), i);
set_block_num (i, BLOCK_NUM (insn));
SET_SRC (pat) = reg;
/* un-recognize this pattern since it's probably different now. */
INSN_CODE (insn) = -1;
gcse_create_count++;
}
}
}
/* Store motion code. */
/* This is used to communicate the target bitvector we want to use in the
reg_set_info routine when called via the note_stores mechanism. */
static sbitmap * regvec;
/* Used in computing the reverse edge graph bit vectors. */
static sbitmap * st_antloc;
/* Global holding the number of store expressions we are dealing with. */
static int num_stores;
/* Checks to set if we need to mark a register set. Called from note_stores. */
static void
reg_set_info (dest, setter, data)
rtx dest, setter ATTRIBUTE_UNUSED;
void * data ATTRIBUTE_UNUSED;
{
if (GET_CODE (dest) == SUBREG)
dest = SUBREG_REG (dest);
if (GET_CODE (dest) == REG)
SET_BIT (*regvec, REGNO (dest));
}
/* Return non-zero if the register operands of expression X are killed
anywhere in basic block BB. */
static int
store_ops_ok (x, bb)
rtx x;
int bb;
{
int i;
enum rtx_code code;
const char * fmt;
/* Repeat is used to turn tail-recursion into iteration. */
repeat:
if (x == 0)
return 1;
code = GET_CODE (x);
switch (code)
{
case REG:
/* If a reg has changed after us in this
block, the operand has been killed. */
return TEST_BIT (reg_set_in_block[bb], REGNO (x));
case MEM:
x = XEXP (x, 0);
goto repeat;
case PRE_DEC:
case PRE_INC:
case POST_DEC:
case POST_INC:
return 0;
case PC:
case CC0: /*FIXME*/
case CONST:
case CONST_INT:
case CONST_DOUBLE:
case SYMBOL_REF:
case LABEL_REF:
case ADDR_VEC:
case ADDR_DIFF_VEC:
return 1;
default:
break;
}
i = GET_RTX_LENGTH (code) - 1;
fmt = GET_RTX_FORMAT (code);
for (; i >= 0; i--)
{
if (fmt[i] == 'e')
{
rtx tem = XEXP (x, i);
/* If we are about to do the last recursive call
needed at this level, change it into iteration.
This function is called enough to be worth it. */
if (i == 0)
{
x = tem;
goto repeat;
}
if (! store_ops_ok (tem, bb))
return 0;
}
else if (fmt[i] == 'E')
{
int j;
for (j = 0; j < XVECLEN (x, i); j++)
{
if (! store_ops_ok (XVECEXP (x, i, j), bb))
return 0;
}
}
}
return 1;
}
/* Determine whether insn is MEM store pattern that we will consider moving. */
static void
find_moveable_store (insn)
rtx insn;
{
struct ls_expr * ptr;
rtx dest = PATTERN (insn);
if (GET_CODE (dest) != SET)
return;
dest = SET_DEST (dest);
if (GET_CODE (dest) != MEM || MEM_VOLATILE_P (dest)
|| GET_MODE (dest) == BLKmode)
return;
if (GET_CODE (XEXP (dest, 0)) != SYMBOL_REF)
return;
if (rtx_varies_p (XEXP (dest, 0), 0))
return;
ptr = ldst_entry (dest);
ptr->stores = alloc_INSN_LIST (insn, ptr->stores);
}
/* Perform store motion. Much like gcse, except we move expressions the
other way by looking at the flowgraph in reverse. */
static int
compute_store_table ()
{
int bb, ret;
unsigned regno;
rtx insn, pat;
max_gcse_regno = max_reg_num ();
reg_set_in_block = (sbitmap *) sbitmap_vector_alloc (n_basic_blocks,
max_gcse_regno);
sbitmap_vector_zero (reg_set_in_block, n_basic_blocks);
pre_ldst_mems = 0;
/* Find all the stores we care about. */
for (bb = 0; bb < n_basic_blocks; bb++)
{
regvec = & (reg_set_in_block[bb]);
for (insn = BLOCK_END (bb);
insn && insn != PREV_INSN (BLOCK_HEAD (bb));
insn = PREV_INSN (insn))
{
#ifdef NON_SAVING_SETJMP
if (NON_SAVING_SETJMP && GET_CODE (insn) == NOTE
&& NOTE_LINE_NUMBER (insn) == NOTE_INSN_SETJMP)
{
for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
SET_BIT (reg_set_in_block[bb], regno);
continue;
}
#endif
/* Ignore anything that is not a normal insn. */
if (GET_RTX_CLASS (GET_CODE (insn)) != 'i')
continue;
if (GET_CODE (insn) == CALL_INSN)
{
for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
if ((call_used_regs[regno]
&& regno != STACK_POINTER_REGNUM
#if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
&& regno != HARD_FRAME_POINTER_REGNUM
#endif
#if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
&& ! (regno == ARG_POINTER_REGNUM && fixed_regs[regno])
#endif
#if defined (PIC_OFFSET_TABLE_REGNUM) && !defined (PIC_OFFSET_TABLE_REG_CALL_CLOBBERED)
&& ! (regno == PIC_OFFSET_TABLE_REGNUM && flag_pic)
#endif
&& regno != FRAME_POINTER_REGNUM)
|| global_regs[regno])
SET_BIT (reg_set_in_block[bb], regno);
}
pat = PATTERN (insn);
note_stores (pat, reg_set_info, NULL);
/* Now that we've marked regs, look for stores. */
if (GET_CODE (pat) == SET)
find_moveable_store (insn);
}
}
ret = enumerate_ldsts ();
if (gcse_file)
{
fprintf (gcse_file, "Store Motion Expressions.\n");
print_ldst_list (gcse_file);
}
return ret;
}
/* Check to see if the load X is aliased with STORE_PATTERN. */
static int
load_kills_store (x, store_pattern)
rtx x, store_pattern;
{
if (true_dependence (x, GET_MODE (x), store_pattern, rtx_addr_varies_p))
return 1;
return 0;
}
/* Go through the entire insn X, looking for any loads which might alias
STORE_PATTERN. Return 1 if found. */
static int
find_loads (x, store_pattern)
rtx x, store_pattern;
{
const char * fmt;
int i,j;
int ret = 0;
if (GET_CODE (x) == SET)
x = SET_SRC (x);
if (GET_CODE (x) == MEM)
{
if (load_kills_store (x, store_pattern))
return 1;
}
/* Recursively process the insn. */
fmt = GET_RTX_FORMAT (GET_CODE (x));
for (i = GET_RTX_LENGTH (GET_CODE (x)) - 1; i >= 0 && !ret; i--)
{
if (fmt[i] == 'e')
ret |= find_loads (XEXP (x, i), store_pattern);
else if (fmt[i] == 'E')
for (j = XVECLEN (x, i) - 1; j >= 0; j--)
ret |= find_loads (XVECEXP (x, i, j), store_pattern);
}
return ret;
}
/* Check if INSN kills the store pattern X (is aliased with it).
Return 1 if it it does. */
static int
store_killed_in_insn (x, insn)
rtx x, insn;
{
if (GET_RTX_CLASS (GET_CODE (insn)) != 'i')
return 0;
if (GET_CODE (insn) == CALL_INSN)
{
if (CONST_CALL_P (insn))
return 0;
else
return 1;
}
if (GET_CODE (PATTERN (insn)) == SET)
{
rtx pat = PATTERN (insn);
/* Check for memory stores to aliased objects. */
if (GET_CODE (SET_DEST (pat)) == MEM && !expr_equiv_p (SET_DEST (pat), x))
/* pretend its a load and check for aliasing. */
if (find_loads (SET_DEST (pat), x))
return 1;
return find_loads (SET_SRC (pat), x);
}
else
return find_loads (PATTERN (insn), x);
}
/* Returns 1 if the expression X is loaded or clobbered on or after INSN
within basic block BB. */
static int
store_killed_after (x, insn, bb)
rtx x, insn;
int bb;
{
rtx last = BLOCK_END (bb);
if (insn == last)
return 0;
/* Check if the register operands of the store are OK in this block.
Note that if registers are changed ANYWHERE in the block, we'll
decide we can't move it, regardless of whether it changed above
or below the store. This could be improved by checking the register
operands while lookinng for aliasing in each insn. */
if (!store_ops_ok (XEXP (x, 0), bb))
return 1;
for ( ; insn && insn != NEXT_INSN (last); insn = NEXT_INSN (insn))
if (store_killed_in_insn (x, insn))
return 1;
return 0;
}
/* Returns 1 if the expression X is loaded or clobbered on or before INSN
within basic block BB. */
static int
store_killed_before (x, insn, bb)
rtx x, insn;
int bb;
{
rtx first = BLOCK_HEAD (bb);
if (insn == first)
return store_killed_in_insn (x, insn);
/* Check if the register operands of the store are OK in this block.
Note that if registers are changed ANYWHERE in the block, we'll
decide we can't move it, regardless of whether it changed above
or below the store. This could be improved by checking the register
operands while lookinng for aliasing in each insn. */
if (!store_ops_ok (XEXP (x, 0), bb))
return 1;
for ( ; insn && insn != PREV_INSN (first); insn = PREV_INSN (insn))
if (store_killed_in_insn (x, insn))
return 1;
return 0;
}
#define ANTIC_STORE_LIST(x) ((x)->loads)
#define AVAIL_STORE_LIST(x) ((x)->stores)
/* Given the table of available store insns at the end of blocks,
determine which ones are not killed by aliasing, and generate
the appropriate vectors for gen and killed. */
static void
build_store_vectors ()
{
int bb;
rtx insn, st;
struct ls_expr * ptr;
/* Build the gen_vector. This is any store in the table which is not killed
by aliasing later in its block. */
ae_gen = (sbitmap *) sbitmap_vector_alloc (n_basic_blocks, num_stores);
sbitmap_vector_zero (ae_gen, n_basic_blocks);
st_antloc = (sbitmap *) sbitmap_vector_alloc (n_basic_blocks, num_stores);
sbitmap_vector_zero (st_antloc, n_basic_blocks);
for (ptr = first_ls_expr (); ptr != NULL; ptr = next_ls_expr (ptr))
{
/* Put all the stores into either the antic list, or the avail list,
or both. */
rtx store_list = ptr->stores;
ptr->stores = NULL_RTX;
for (st = store_list; st != NULL; st = XEXP (st, 1))
{
insn = XEXP (st, 0);
bb = BLOCK_NUM (insn);
if (!store_killed_after (ptr->pattern, insn, bb))
{
/* If we've already seen an availale expression in this block,
we can delete the one we saw already (It occurs earlier in
the block), and replace it with this one). We'll copy the
old SRC expression to an unused register in case there
are any side effects. */
if (TEST_BIT (ae_gen[bb], ptr->index))
{
/* Find previous store. */
rtx st;
for (st = AVAIL_STORE_LIST (ptr); st ; st = XEXP (st, 1))
if (BLOCK_NUM (XEXP (st, 0)) == bb)
break;
if (st)
{
rtx r = gen_reg_rtx (GET_MODE (ptr->pattern));
if (gcse_file)
fprintf(gcse_file, "Removing redundant store:\n");
replace_store_insn (r, XEXP (st, 0), bb);
XEXP (st, 0) = insn;
continue;
}
}
SET_BIT (ae_gen[bb], ptr->index);
AVAIL_STORE_LIST (ptr) = alloc_INSN_LIST (insn,
AVAIL_STORE_LIST (ptr));
}
if (!store_killed_before (ptr->pattern, insn, bb))
{
SET_BIT (st_antloc[BLOCK_NUM (insn)], ptr->index);
ANTIC_STORE_LIST (ptr) = alloc_INSN_LIST (insn,
ANTIC_STORE_LIST (ptr));
}
}
/* Free the original list of store insns. */
free_INSN_LIST_list (&store_list);
}
ae_kill = (sbitmap *) sbitmap_vector_alloc (n_basic_blocks, num_stores);
sbitmap_vector_zero (ae_kill, n_basic_blocks);
transp = (sbitmap *) sbitmap_vector_alloc (n_basic_blocks, num_stores);
sbitmap_vector_zero (transp, n_basic_blocks);
for (ptr = first_ls_expr (); ptr != NULL; ptr = next_ls_expr (ptr))
for (bb = 0; bb < n_basic_blocks; bb++)
{
if (store_killed_after (ptr->pattern, BLOCK_HEAD (bb), bb))
{
/* The anticipatable expression is not killed if it's gen'd. */
/*
We leave this check out for now. If we have a code sequence
in a block which looks like:
ST MEMa = x
L y = MEMa
ST MEMa = z
We should flag this as having an ANTIC expression, NOT
transparent, NOT killed, and AVAIL.
Unfortunately, since we haven't re-written all loads to
use the reaching reg, we'll end up doing an incorrect
Load in the middle here if we push the store down. It happens in
gcc.c-torture/execute/960311-1.c with -O3
If we always kill it in this case, we'll sometimes do
uneccessary work, but it shouldn't actually hurt anything.
if (!TEST_BIT (ae_gen[bb], ptr->index)). */
SET_BIT (ae_kill[bb], ptr->index);
}
else
SET_BIT (transp[bb], ptr->index);
}
/* Any block with no exits calls some non-returning function, so
we better mark the store killed here, or we might not store to
it at all. If we knew it was abort, we wouldn't have to store,
but we don't know that for sure. */
if (gcse_file)
{
fprintf (gcse_file, "ST_avail and ST_antic (shown under loads..)\n");
print_ldst_list (gcse_file);
dump_sbitmap_vector (gcse_file, "st_antloc", "", st_antloc, n_basic_blocks);
dump_sbitmap_vector (gcse_file, "st_kill", "", ae_kill, n_basic_blocks);
dump_sbitmap_vector (gcse_file, "Transpt", "", transp, n_basic_blocks);
dump_sbitmap_vector (gcse_file, "st_avloc", "", ae_gen, n_basic_blocks);
}
}
/* Insert an instruction at the begining of a basic block, and update
the BLOCK_HEAD if needed. */
static void
insert_insn_start_bb (insn, bb)
rtx insn;
int bb;
{
/* Insert at start of successor block. */
rtx prev = PREV_INSN (BLOCK_HEAD (bb));
rtx before = BLOCK_HEAD (bb);
while (before != 0)
{
if (GET_CODE (before) != CODE_LABEL
&& (GET_CODE (before) != NOTE
|| NOTE_LINE_NUMBER (before) != NOTE_INSN_BASIC_BLOCK))
break;
prev = before;
if (prev == BLOCK_END (bb))
break;
before = NEXT_INSN (before);
}
insn = emit_insn_after (insn, prev);
if (prev == BLOCK_END (bb))
BLOCK_END (bb) = insn;
while (insn != prev)
{
set_block_num (insn, bb);
insn = PREV_INSN (insn);
}
if (gcse_file)
{
fprintf (gcse_file, "STORE_MOTION insert store at start of BB %d:\n",
bb);
print_inline_rtx (gcse_file, insn, 6);
fprintf (gcse_file, "\n");
}
}
/* This routine will insert a store on an edge. EXPR is the ldst entry for
the memory reference, and E is the edge to insert it on. Returns non-zero
if an edge insertion was performed. */
static int
insert_store (expr, e)
struct ls_expr * expr;
edge e;
{
rtx reg, insn;
int bb;
edge tmp;
/* We did all the deleted before this insert, so if we didn't delete a
store, then we haven't set the reaching reg yet either. */
if (expr->reaching_reg == NULL_RTX)
return 0;
reg = expr->reaching_reg;
insn = gen_move_insn (expr->pattern, reg);
/* If we are inserting this expression on ALL predecessor edges of a BB,
insert it at the start of the BB, and reset the insert bits on the other
edges so we don;t try to insert it on the other edges. */
bb = e->dest->index;
for (tmp = e->dest->pred; tmp ; tmp = tmp->pred_next)
{
int index = EDGE_INDEX (edge_list, tmp->src, tmp->dest);
if (index == EDGE_INDEX_NO_EDGE)
abort ();
if (! TEST_BIT (pre_insert_map[index], expr->index))
break;
}
/* If tmp is NULL, we found an insertion on every edge, blank the
insertion vector for these edges, and insert at the start of the BB. */
if (!tmp && bb != EXIT_BLOCK)
{
for (tmp = e->dest->pred; tmp ; tmp = tmp->pred_next)
{
int index = EDGE_INDEX (edge_list, tmp->src, tmp->dest);
RESET_BIT (pre_insert_map[index], expr->index);
}
insert_insn_start_bb (insn, bb);
return 0;
}
/* We can't insert on this edge, so we'll insert at the head of the
successors block. See Morgan, sec 10.5. */
if ((e->flags & EDGE_ABNORMAL) == EDGE_ABNORMAL)
{
insert_insn_start_bb (insn, bb);
return 0;
}
insert_insn_on_edge (insn, e);
if (gcse_file)
{
fprintf (gcse_file, "STORE_MOTION insert insn on edge (%d, %d):\n",
e->src->index, e->dest->index);
print_inline_rtx (gcse_file, insn, 6);
fprintf (gcse_file, "\n");
}
return 1;
}
/* This routine will replace a store with a SET to a specified register. */
static void
replace_store_insn (reg, del, bb)
rtx reg, del;
int bb;
{
rtx insn;
insn = gen_move_insn (reg, SET_SRC (PATTERN (del)));
insn = emit_insn_after (insn, del);
set_block_num (insn, bb);
if (gcse_file)
{
fprintf (gcse_file,
"STORE_MOTION delete insn in BB %d:\n ", bb);
print_inline_rtx (gcse_file, del, 6);
fprintf(gcse_file, "\nSTORE MOTION replaced with insn:\n ");
print_inline_rtx (gcse_file, insn, 6);
fprintf(gcse_file, "\n");
}
if (BLOCK_END (bb) == del)
BLOCK_END (bb) = insn;
if (BLOCK_HEAD (bb) == del)
BLOCK_HEAD (bb) = insn;
delete_insn (del);
}
/* Delete a store, but copy the value that would have been stored into
the reaching_reg for later storing. */
static void
delete_store (expr, bb)
struct ls_expr * expr;
int bb;
{
rtx reg, i, del;
if (expr->reaching_reg == NULL_RTX)
expr->reaching_reg = gen_reg_rtx (GET_MODE (expr->pattern));
/* If there is more than 1 store, the earlier ones will be dead,
but it doesn't hurt to replace them here. */
reg = expr->reaching_reg;
for (i = AVAIL_STORE_LIST (expr); i; i = XEXP (i, 1))
{
del = XEXP (i, 0);
if (BLOCK_NUM (del) == bb)
{
/* We know there is only one since we deleted redundant
ones during the available computation. */
replace_store_insn (reg, del, bb);
break;
}
}
}
/* Free memory used by store motion. */
static void
free_store_memory ()
{
free_ldst_mems ();
if (ae_gen)
free (ae_gen);
if (ae_kill)
free (ae_kill);
if (transp)
free (transp);
if (st_antloc)
free (st_antloc);
if (pre_insert_map)
free (pre_insert_map);
if (pre_delete_map)
free (pre_delete_map);
if (reg_set_in_block)
free (reg_set_in_block);
ae_gen = ae_kill = transp = st_antloc = NULL;
pre_insert_map = pre_delete_map = reg_set_in_block = NULL;
}
/* Perform store motion. Much like gcse, except we move expressions the
other way by looking at the flowgraph in reverse. */
static void
store_motion ()
{
int x;
struct ls_expr * ptr;
int update_flow = 0;
if (gcse_file)
{
fprintf (gcse_file, "before store motion\n");
print_rtl (gcse_file, get_insns ());
}
init_alias_analysis ();
/* Find all the stores that are live to the end of their block. */
num_stores = compute_store_table ();
if (num_stores == 0)
{
free (reg_set_in_block);
end_alias_analysis ();
return;
}
/* Now compute whats actually available to move. */
add_noreturn_fake_exit_edges ();
build_store_vectors ();
edge_list = pre_edge_rev_lcm (gcse_file, num_stores, transp, ae_gen,
st_antloc, ae_kill, &pre_insert_map,
&pre_delete_map);
/* Now we want to insert the new stores which are going to be needed. */
for (ptr = first_ls_expr (); ptr != NULL; ptr = next_ls_expr (ptr))
{
for (x = 0; x < n_basic_blocks; x++)
if (TEST_BIT (pre_delete_map[x], ptr->index))
delete_store (ptr, x);
for (x = 0; x < NUM_EDGES (edge_list); x++)
if (TEST_BIT (pre_insert_map[x], ptr->index))
update_flow |= insert_store (ptr, INDEX_EDGE (edge_list, x));
}
if (update_flow)
commit_edge_insertions ();
free_store_memory ();
free_edge_list (edge_list);
remove_fake_edges ();
end_alias_analysis ();
}
gcc/invoke.texi
...@@ -241,7 +241,7 @@ in the following sections. ...@@ -241,7 +241,7 @@ in the following sections.
-fcse-follow-jumps -fcse-skip-blocks -fdata-sections -fdce @gol -fcse-follow-jumps -fcse-skip-blocks -fdata-sections -fdce @gol
-fdelayed-branch -fdelete-null-pointer-checks @gol -fdelayed-branch -fdelete-null-pointer-checks @gol
-fexpensive-optimizations -ffast-math -ffloat-store @gol -fexpensive-optimizations -ffast-math -ffloat-store @gol
-fforce-addr -fforce-mem -ffunction-sections -fgcse @gol -fforce-addr -fforce-mem -ffunction-sections -fgcse -fgcse-lm -fgcse-sm @gol
-finline-functions -finline-limit=@var{n} -fkeep-inline-functions @gol -finline-functions -finline-limit=@var{n} -fkeep-inline-functions @gol
-fkeep-static-consts -fmove-all-movables @gol -fkeep-static-consts -fmove-all-movables @gol
-fno-default-inline -fno-defer-pop @gol -fno-default-inline -fno-defer-pop @gol
...@@ -3034,6 +3034,18 @@ Run the loop optimizer twice. ...@@ -3034,6 +3034,18 @@ Run the loop optimizer twice.
Perform a global common subexpression elimination pass. Perform a global common subexpression elimination pass.
This pass also performs global constant and copy propagation. This pass also performs global constant and copy propagation.
@item -fgcse-lm
When -fgcse-lm is enabled, global common subexpression elimination will
attempt to move loads which are only killed by stores into themselves. This
allows a loop containing a load/store sequence to be changed to a load outside
the loop, and a copy/store within the loop.
@item -fgcse-sm
When -fgcse-sm is enabled, A store motion pass is run after global common
subexpression elimination. This pass will attempt to move stores out of loops.
When used in conjunction with -fgcse-lm, loops containing a load/store sequence
can be changed to a load before the loop and a store after the loop.
@item -fdelete-null-pointer-checks @item -fdelete-null-pointer-checks
Use global dataflow analysis to identify and eliminate useless null Use global dataflow analysis to identify and eliminate useless null
pointer checks. Programs which rely on NULL pointer dereferences @emph{not} pointer checks. Programs which rely on NULL pointer dereferences @emph{not}
......
gcc/rtl.h
...@@ -2031,6 +2031,9 @@ extern void fancy_abort PARAMS ((const char *, int, const char *)) ...@@ -2031,6 +2031,9 @@ extern void fancy_abort PARAMS ((const char *, int, const char *))
extern rtx canon_rtx PARAMS ((rtx)); extern rtx canon_rtx PARAMS ((rtx));
extern int true_dependence PARAMS ((rtx, enum machine_mode, rtx, extern int true_dependence PARAMS ((rtx, enum machine_mode, rtx,
int (*)(rtx, int))); int (*)(rtx, int)));
extern rtx get_addr PARAMS ((rtx));
extern int canon_true_dependence PARAMS ((rtx, enum machine_mode, rtx,
rtx, int (*)(rtx, int)));
extern int read_dependence PARAMS ((rtx, rtx)); extern int read_dependence PARAMS ((rtx, rtx));
extern int anti_dependence PARAMS ((rtx, rtx)); extern int anti_dependence PARAMS ((rtx, rtx));
extern int output_dependence PARAMS ((rtx, rtx)); extern int output_dependence PARAMS ((rtx, rtx));
......
gcc/toplev.c
...@@ -668,6 +668,18 @@ static int flag_gcse; ...@@ -668,6 +668,18 @@ static int flag_gcse;
static int flag_delete_null_pointer_checks; static int flag_delete_null_pointer_checks;
/* Nonzero means to do the enhanced load motion during gcse, which trys
to hoist loads by not killing them when a store to the same location
is seen. */
int flag_gcse_lm = 1;
/* Nonzero means to perform store motion after gcse, which will try to
move stores closer to the exit block. Its not very effective without
flag_gcse_lm. */
int flag_gcse_sm = 1;
/* Nonzero means to rerun cse after loop optimization. This increases /* Nonzero means to rerun cse after loop optimization. This increases
compilation time about 20% and picks up a few more common expressions. */ compilation time about 20% and picks up a few more common expressions. */
...@@ -1047,6 +1059,10 @@ lang_independent_options f_options[] = ...@@ -1047,6 +1059,10 @@ lang_independent_options f_options[] =
"Attempt to fill delay slots of branch instructions" }, "Attempt to fill delay slots of branch instructions" },
{"gcse", &flag_gcse, 1, {"gcse", &flag_gcse, 1,
"Perform the global common subexpression elimination" }, "Perform the global common subexpression elimination" },
{"gcse-lm", &flag_gcse_lm, 1,
"Perform enhanced load motion during global subexpression elimination" },
{"gcse-sm", &flag_gcse_sm, 1,
"Perform store motion after global subexpression elimination" },
{"rerun-cse-after-loop", &flag_rerun_cse_after_loop, 1, {"rerun-cse-after-loop", &flag_rerun_cse_after_loop, 1,
"Run CSE pass after loop optimisations"}, "Run CSE pass after loop optimisations"},
{"rerun-loop-opt", &flag_rerun_loop_opt, 1, {"rerun-loop-opt", &flag_rerun_loop_opt, 1,
......
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