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riscv-gcc-1
Commit 2e6be65e by Eric Botcazou Committed by Eric Botcazou
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dce.c (init_dce): Only initialize the obstacks for the fast pass. 

	* dce.c (init_dce): Only initialize the obstacks for the fast pass.
	(fini_dce): Only release them for the fast pass.
	(end_ud_dce): Delete.
	(rest_of_handle_ud_dce): Do not modify df_in_progress.
	Call fini_dce instead of end_ud_dce.
	(rest_of_handle_fast_dce): Do not modify df_in_progress.
	(run_fast_df_dce): Reset df_in_progress to false on exit.

From-SVN: r129384
parent 053cc380
Showing with 71 additions and 55 deletions
gcc/ChangeLog
2007-10-16 Eric Botcazou <ebotcazou@libertysurf.fr>
* dce.c (init_dce): Only initialize the obstacks for the fast pass.
(fini_dce): Only release them for the fast pass.
(end_ud_dce): Delete.
(rest_of_handle_ud_dce): Do not modify df_in_progress.
Call fini_dce instead of end_ud_dce.
(rest_of_handle_fast_dce): Do not modify df_in_progress.
(run_fast_df_dce): Reset df_in_progress to false on exit.
2007-10-16 Paolo Bonzini <bonzini@gnu.org>
Maxim Kuvyrkov <maxim@codesourcery.com>
gcc/dce.c
......@@ -42,7 +42,8 @@ DEF_VEC_ALLOC_I(int,heap);
Core mark/delete routines
------------------------------------------------------------------------- */
/* The data-flow information needed by this pass. */
/* True if we are invoked while the df engine is running; in this case,
we don't want to reenter it. */
static bool df_in_progress = false;
/* True if we deleted at least one instruction. */
......@@ -52,10 +53,13 @@ static bool something_changed;
yet been processed. */
static VEC(rtx,heap) *worklist;
/* Bitmap of instructions marked as needed indexed by INSN_UID. */
static sbitmap marked;
/* Bitmap obstacks used for block processing by the fast algorithm. */
static bitmap_obstack dce_blocks_bitmap_obstack;
static bitmap_obstack dce_tmp_bitmap_obstack;
static sbitmap marked = NULL;
/* A subroutine for which BODY is part of the instruction being tested;
either the top-level pattern, or an element of a PARALLEL. The
......@@ -88,6 +92,7 @@ deletable_insn_p_1 (rtx body)
}
}
/* Return true if INSN is a normal instruction that can be deleted by
the DCE pass. */
......@@ -133,7 +138,7 @@ deletable_insn_p (rtx insn, bool fast)
}
/* Return true if INSN has not been marked as needed. */
/* Return true if INSN has been marked as needed. */
static inline int
marked_insn_p (rtx insn)
......@@ -198,28 +203,6 @@ mark_nonreg_stores (rtx body, rtx insn, bool fast)
}
/* Initialize global variables for a new DCE pass. */
static void
init_dce (bool fast)
{
if (!df_in_progress)
{
if (!fast)
df_chain_add_problem (DF_UD_CHAIN);
df_analyze ();
}
if (dump_file)
df_dump (dump_file);
bitmap_obstack_initialize (&dce_blocks_bitmap_obstack);
bitmap_obstack_initialize (&dce_tmp_bitmap_obstack);
marked = sbitmap_alloc (get_max_uid () + 1);
sbitmap_zero (marked);
}
/* Delete all REG_EQUAL notes of the registers INSN writes, to prevent
bad dangling REG_EQUAL notes. */
......@@ -263,6 +246,7 @@ delete_unmarked_insns (void)
rtx insn, next;
something_changed = false;
FOR_EACH_BB (bb)
FOR_BB_INSNS_SAFE (bb, insn, next)
if (INSN_P (insn))
......@@ -309,6 +293,7 @@ delete_unmarked_insns (void)
/* Mark all insns using DELETE_PARM in the libcall that contains
START_INSN. */
static void
mark_libcall (rtx start_insn, bool delete_parm)
{
......@@ -416,6 +401,7 @@ mark_artificial_uses (void)
}
}
/* Mark every instruction that defines a register value that INSN uses. */
static void
......@@ -443,11 +429,44 @@ mark_reg_dependencies (rtx insn)
}
/* Initialize global variables for a new DCE pass. */
static void
end_ud_dce (void)
init_dce (bool fast)
{
if (!df_in_progress)
{
if (!fast)
df_chain_add_problem (DF_UD_CHAIN);
df_analyze ();
}
if (dump_file)
df_dump (dump_file);
if (fast)
{
bitmap_obstack_initialize (&dce_blocks_bitmap_obstack);
bitmap_obstack_initialize (&dce_tmp_bitmap_obstack);
}
marked = sbitmap_alloc (get_max_uid () + 1);
sbitmap_zero (marked);
}
/* Free the data allocated by init_dce. */
static void
fini_dce (bool fast)
{
sbitmap_free (marked);
gcc_assert (VEC_empty (rtx, worklist));
if (fast)
{
bitmap_obstack_release (&dce_blocks_bitmap_obstack);
bitmap_obstack_release (&dce_tmp_bitmap_obstack);
}
}
......@@ -458,7 +477,6 @@ rest_of_handle_ud_dce (void)
{
rtx insn;
df_in_progress = false;
init_dce (false);
prescan_insns_for_dce (false);
......@@ -468,12 +486,13 @@ rest_of_handle_ud_dce (void)
insn = VEC_pop (rtx, worklist);
mark_reg_dependencies (insn);
}
/* Before any insns are deleted, we must remove the chains since
they are not bidirectional. */
df_remove_problem (df_chain);
delete_unmarked_insns ();
end_ud_dce ();
fini_dce (false);
return 0;
}
......@@ -503,25 +522,12 @@ struct tree_opt_pass pass_ud_rtl_dce =
'w' /* letter */
};
/* -------------------------------------------------------------------------
Fast DCE functions
------------------------------------------------------------------------- */
/* Free the data allocated by init_dce. */
static void
fini_dce (void)
{
sbitmap_free (marked);
bitmap_obstack_release (&dce_blocks_bitmap_obstack);
bitmap_obstack_release (&dce_tmp_bitmap_obstack);
df_in_progress = false;
}
/* Process basic block BB. Return true if the live_in set has
changed. */
/* Process basic block BB. Return true if the live_in set has changed. */
static bool
dce_process_block (basic_block bb, bool redo_out)
......@@ -655,12 +661,14 @@ dce_process_block (basic_block bb, bool redo_out)
return block_changed;
}
/* Perform fast DCE once initialization is done. */
static void
fast_dce (void)
{
int *postorder = df_get_postorder (DF_BACKWARD);
int n_blocks = df_get_n_blocks (DF_BACKWARD);
int i;
/* The set of blocks that have been seen on this iteration. */
bitmap processed = BITMAP_ALLOC (&dce_blocks_bitmap_obstack);
/* The set of blocks that need to have the out vectors reset because
......@@ -668,8 +676,7 @@ fast_dce (void)
bitmap redo_out = BITMAP_ALLOC (&dce_blocks_bitmap_obstack);
bitmap all_blocks = BITMAP_ALLOC (&dce_blocks_bitmap_obstack);
bool global_changed = true;
int loop_count = 0;
int i, loop_count = 0;
prescan_insns_for_dce (true);
......@@ -745,15 +752,14 @@ fast_dce (void)
}
/* Callback for running pass_rtl_dce. */
/* Fast DCE. */
static unsigned int
rest_of_handle_fast_dce (void)
{
init_dce (true);
fast_dce ();
fini_dce ();
df_in_progress = false;
fini_dce (true);
return 0;
}
......@@ -765,8 +771,7 @@ rest_of_handle_fast_dce (void)
info, and then returns to allow the rest of the problems to be run.
This can be called by elsewhere but it will not update the bit
vectors for any other problems than LR.
*/
vectors for any other problems than LR. */
void
run_fast_df_dce (void)
......@@ -781,10 +786,13 @@ run_fast_df_dce (void)
df_in_progress = true;
rest_of_handle_fast_dce ();
df_in_progress = false;
df_set_flags (old_flags);
}
}
static bool
gate_fast_dce (void)
{
......@@ -792,8 +800,7 @@ gate_fast_dce (void)
}
/* Run a fast DCE pass and return true if any instructions were
deleted. */
/* Run a fast DCE pass and return true if any instructions were deleted. */
bool
run_fast_dce (void)
......@@ -820,4 +827,3 @@ struct tree_opt_pass pass_fast_rtl_dce =
TODO_ggc_collect, /* todo_flags_finish */
'w' /* letter */
};
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