/* Instruction scheduling pass. This file computes dependencies between
instructions.
Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998,
- 1999, 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
+ 1999, 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
Contributed by Michael Tiemann (tiemann@cygnus.com) Enhanced by,
and currently maintained by, Jim Wilson (wilson@cygnus.com)
#include "rtl.h"
#include "tm_p.h"
#include "hard-reg-set.h"
-#include "basic-block.h"
#include "regs.h"
#include "function.h"
#include "flags.h"
#include "df.h"
-static regset_head reg_pending_sets_head;
-static regset_head reg_pending_clobbers_head;
-static regset_head reg_pending_uses_head;
-
static regset reg_pending_sets;
static regset reg_pending_clobbers;
static regset reg_pending_uses;
static bitmap_head *true_dependency_cache;
static bitmap_head *anti_dependency_cache;
static bitmap_head *output_dependency_cache;
-int cache_size;
+static int cache_size;
/* To speed up checking consistency of formed forward insn
dependencies we use the following cache. Another possible solution
static int deps_may_trap_p (rtx);
static void add_dependence_list (rtx, rtx, enum reg_note);
static void add_dependence_list_and_free (rtx, rtx *, enum reg_note);
-static void set_sched_group_p (rtx);
+static void delete_all_dependences (rtx);
+static void fixup_sched_groups (rtx);
static void flush_pending_lists (struct deps *, rtx, int, int);
static void sched_analyze_1 (struct deps *, rtx, rtx);
}
}
-/* Set SCHED_GROUP_P and care for the rest of the bookkeeping that
- goes along with that. */
+/* Clear all dependencies for an insn. */
static void
-set_sched_group_p (rtx insn)
+delete_all_dependences (rtx insn)
{
- rtx prev;
+ /* Clear caches, if they exist, as well as free the dependence. */
- SCHED_GROUP_P (insn) = 1;
+#ifdef INSN_SCHEDULING
+ if (true_dependency_cache != NULL)
+ {
+ bitmap_clear (&true_dependency_cache[INSN_LUID (insn)]);
+ bitmap_clear (&anti_dependency_cache[INSN_LUID (insn)]);
+ bitmap_clear (&output_dependency_cache[INSN_LUID (insn)]);
+ }
+#endif
- prev = prev_nonnote_insn (insn);
- add_dependence (insn, prev, REG_DEP_ANTI);
+ free_INSN_LIST_list (&LOG_LINKS (insn));
+}
+
+/* All insns in a scheduling group except the first should only have
+ dependencies on the previous insn in the group. So we find the
+ first instruction in the scheduling group by walking the dependence
+ chains backwards. Then we add the dependencies for the group to
+ the previous nonnote insn. */
+
+static void
+fixup_sched_groups (rtx insn)
+{
+ rtx link;
+
+ for (link = LOG_LINKS (insn); link ; link = XEXP (link, 1))
+ {
+ rtx i = insn;
+ do
+ {
+ i = prev_nonnote_insn (i);
+
+ if (XEXP (link, 0) == i)
+ goto next_link;
+ } while (SCHED_GROUP_P (i));
+ add_dependence (i, XEXP (link, 0), REG_NOTE_KIND (link));
+ next_link:;
+ }
+
+ delete_all_dependences (insn);
+
+ if (BLOCK_FOR_INSN (insn) == BLOCK_FOR_INSN (prev_nonnote_insn (insn)))
+ add_dependence (insn, prev_nonnote_insn (insn), REG_DEP_ANTI);
}
\f
/* Process an insn's memory dependencies. There are four kinds of
The MEM is a memory reference contained within INSN, which we are saving
so that we can do memory aliasing on it. */
-void
+static void
add_insn_mem_dependence (struct deps *deps, rtx *insn_list, rtx *mem_list,
rtx insn, rtx mem)
{
}
while (GET_CODE (dest) == STRICT_LOW_PART || GET_CODE (dest) == SUBREG
- || GET_CODE (dest) == ZERO_EXTRACT || GET_CODE (dest) == SIGN_EXTRACT)
+ || GET_CODE (dest) == ZERO_EXTRACT)
{
if (GET_CODE (dest) == STRICT_LOW_PART
|| GET_CODE (dest) == ZERO_EXTRACT
- || GET_CODE (dest) == SIGN_EXTRACT
|| read_modify_subreg_p (dest))
{
/* These both read and modify the result. We must handle
sched_analyze_2 (deps, XEXP (dest, 0), insn);
}
- if (GET_CODE (dest) == ZERO_EXTRACT || GET_CODE (dest) == SIGN_EXTRACT)
+ if (GET_CODE (dest) == ZERO_EXTRACT)
{
/* The second and third arguments are values read by this insn. */
sched_analyze_2 (deps, XEXP (dest, 1), insn);
#ifdef HAVE_cc0
case CC0:
/* User of CC0 depends on immediately preceding insn. */
- set_sched_group_p (insn);
+ SCHED_GROUP_P (insn) = 1;
/* Don't move CC0 setter to another block (it can set up the
same flag for previous CC0 users which is safe). */
CANT_MOVE (prev_nonnote_insn (insn)) = 1;
{
rtx link;
- /* Update loop_notes with any notes from this insn. Also determine
- if any of the notes on the list correspond to instruction scheduling
- barriers (loop, eh & setjmp notes, but not range notes). */
+ /* Update loop_notes with any notes from this insn. */
link = loop_notes;
while (XEXP (link, 1))
{
- if (INTVAL (XEXP (link, 0)) == NOTE_INSN_LOOP_BEG
- || INTVAL (XEXP (link, 0)) == NOTE_INSN_LOOP_END
- || INTVAL (XEXP (link, 0)) == NOTE_INSN_EH_REGION_BEG
- || INTVAL (XEXP (link, 0)) == NOTE_INSN_EH_REGION_END)
- reg_pending_barrier = MOVE_BARRIER;
+ gcc_assert (INTVAL (XEXP (link, 0)) == NOTE_INSN_LOOP_BEG
+ || INTVAL (XEXP (link, 0)) == NOTE_INSN_LOOP_END);
+ reg_pending_barrier = MOVE_BARRIER;
link = XEXP (link, 1);
}
XEXP (link, 1) = REG_NOTES (insn);
if (deps->libcall_block_tail_insn)
{
- set_sched_group_p (insn);
+ SCHED_GROUP_P (insn) = 1;
CANT_MOVE (insn) = 1;
}
if (src_regno < FIRST_PSEUDO_REGISTER
|| dest_regno < FIRST_PSEUDO_REGISTER)
{
- /* If we are inside a post-call group right at the start of the
- scheduling region, we must not add a dependency. */
if (deps->in_post_call_group_p == post_call_initial)
- {
- SCHED_GROUP_P (insn) = 1;
- deps->in_post_call_group_p = post_call;
- }
- else
- set_sched_group_p (insn);
+ deps->in_post_call_group_p = post_call;
+
+ SCHED_GROUP_P (insn) = 1;
CANT_MOVE (insn) = 1;
}
else
deps->in_post_call_group_p = not_post_call;
}
}
+
+ /* Fixup the dependencies in the sched group. */
+ if (SCHED_GROUP_P (insn))
+ fixup_sched_groups (insn);
}
/* Analyze every insn between HEAD and TAIL inclusive, creating LOG_LINKS
deps->in_post_call_group_p = post_call;
}
+ /* EH_REGION insn notes can not appear until well after we complete
+ scheduling. */
+ if (NOTE_P (insn))
+ gcc_assert (NOTE_LINE_NUMBER (insn) != NOTE_INSN_EH_REGION_BEG
+ && NOTE_LINE_NUMBER (insn) != NOTE_INSN_EH_REGION_END);
+
/* See comments on reemit_notes as to why we do this.
??? Actually, the reemit_notes just say what is done, not why. */
if (NOTE_P (insn)
- && (NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_BEG
- || NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_END
- || NOTE_LINE_NUMBER (insn) == NOTE_INSN_EH_REGION_BEG
- || NOTE_LINE_NUMBER (insn) == NOTE_INSN_EH_REGION_END))
+ && (NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_BEG
+ || NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_END))
{
- rtx rtx_region;
-
- if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EH_REGION_BEG
- || NOTE_LINE_NUMBER (insn) == NOTE_INSN_EH_REGION_END)
- rtx_region = GEN_INT (NOTE_EH_HANDLER (insn));
- else
- rtx_region = const0_rtx;
-
- loop_notes = alloc_EXPR_LIST (REG_SAVE_NOTE,
- rtx_region,
- loop_notes);
loop_notes = alloc_EXPR_LIST (REG_SAVE_NOTE,
GEN_INT (NOTE_LINE_NUMBER (insn)),
loop_notes);
void
init_deps_global (void)
{
- reg_pending_sets = INITIALIZE_REG_SET (reg_pending_sets_head);
- reg_pending_clobbers = INITIALIZE_REG_SET (reg_pending_clobbers_head);
- reg_pending_uses = INITIALIZE_REG_SET (reg_pending_uses_head);
+ reg_pending_sets = ALLOC_REG_SET (®_obstack);
+ reg_pending_clobbers = ALLOC_REG_SET (®_obstack);
+ reg_pending_uses = ALLOC_REG_SET (®_obstack);
reg_pending_barrier = NOT_A_BARRIER;
}