ia64 scheduling patches, part 1
Bernd Schmidt
bernds@redhat.com
Tue Dec 19 09:30:00 GMT 2000
I'll be checking in patches that implement support for instruction scheduling
on ia64 targets over the next few days. The whole set has bootstrapped on
ia64-linux; I'll run bootstraps for each of the parts on i686-linux.
This first patch only adds a bit of infrastructure. It gets rid of more
references to basic block numbers in the scheduler, adds two new scheduling
macros, allows the scheduler to generate cycle display insns, etc.
Bernd
* haifa-sched.c (rm_line_notes): Arguments are now head and tail,
not block number. All callers and prototype changed.
(set_priorities): Likewise.
(save_line_notes): Add head and tail arguments; all callers and
prototype changed.
(restore_line_notes): Likewise. Don't crash on insns generated
during scheduling.
(schedule_block): Don't use BLOCK_HEAD/BLOCK_END macros.
Call MD_SCHED_INIT with additional argument.
When starting a new cycle, emit cycle_display insns if available.
Don't stop scheduling when encountering a JUMP_INSN, but add another
call to schedule_more_p in the inner loop.
Call MD_SCHED_REORDER2 after scheduling an insn.
Call MD_SCHED_FINISH once all insns are scheduled.
(sched_init): Compensate for the fact that get_block_head_tail
doesn't include leading notes.
* sched-deps.c (free_deps): Free vectors here.
* sched-rgn.c (compute_block_backward_dependencies): Not here.
(last_was_jump): New static variable.
(schedule_more_p): Test it.
(init_ready_list): Initialize it.
(can_schedule_ready_p): Set it if we have a JUMP_INSN.
* config/i386/i386.h (MD_SCHED_INIT): Add new arg.
* config/m32r/m32r.h (MD_SCHED_INIT): Add new arg.
* config/sparc/sparc.h (MD_SCHED_INIT): Add new arg.
* md.texi (cycle_display): Document.
* tm.texi (MD_SCHED_INIT): Document new arg.
(MD_SCHED_FINISH, MD_SCHED_REORDER2): Document.
Index: haifa-sched.c
===================================================================
RCS file: /cvs/gcc/egcs/gcc/haifa-sched.c,v
retrieving revision 1.173
diff -u -p -r1.173 haifa-sched.c
--- haifa-sched.c 2000/12/15 03:40:57 1.173
+++ haifa-sched.c 2000/12/19 17:15:52
@@ -1163,23 +1163,17 @@ no_real_insns_p (head, tail)
return 1;
}
-/* Delete line notes from bb. Save them so they can be later restored
- (in restore_line_notes ()). */
+/* Delete line notes from one block. Save them so they can be later restored
+ (in restore_line_notes). HEAD and TAIL are the boundaries of the
+ block in which notes should be processed. */
void
-rm_line_notes (b)
- int b;
+rm_line_notes (head, tail)
+ rtx head, tail;
{
rtx next_tail;
- rtx tail;
- rtx head;
rtx insn;
- get_block_head_tail (b, &head, &tail);
-
- if (head == tail && (! INSN_P (head)))
- return;
-
next_tail = NEXT_INSN (tail);
for (insn = head; insn != next_tail; insn = NEXT_INSN (insn))
{
@@ -1203,13 +1197,14 @@ rm_line_notes (b)
}
}
-/* Save line number notes for each insn in block B. */
+/* Save line number notes for each insn in block B. HEAD and TAIL are
+ the boundaries of the block in which notes should be processed.*/
void
-save_line_notes (b)
+save_line_notes (b, head, tail)
int b;
+ rtx head, tail;
{
- rtx head, tail;
rtx next_tail;
/* We must use the true line number for the first insn in the block
@@ -1220,28 +1215,30 @@ save_line_notes (b)
rtx line = line_note_head[b];
rtx insn;
- get_block_head_tail (b, &head, &tail);
next_tail = NEXT_INSN (tail);
- for (insn = BLOCK_HEAD (b); insn != next_tail; insn = NEXT_INSN (insn))
+ for (insn = head; insn != next_tail; insn = NEXT_INSN (insn))
if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
line = insn;
else
LINE_NOTE (insn) = line;
}
-/* After block B was scheduled, insert line notes into the insns list. */
+/* After block B was scheduled, insert line notes into the insns list.
+ HEAD and TAIL are the boundaries of the block in which notes should
+ be processed.*/
void
-restore_line_notes (b)
+restore_line_notes (b, head, tail)
int b;
+ rtx head, tail;
{
rtx line, note, prev, new;
int added_notes = 0;
- rtx head, next_tail, insn;
+ rtx next_tail, insn;
- head = BLOCK_HEAD (b);
- next_tail = NEXT_INSN (BLOCK_END (b));
+ head = head;
+ next_tail = NEXT_INSN (tail);
/* Determine the current line-number. We want to know the current
line number of the first insn of the block here, in case it is
@@ -1263,6 +1260,7 @@ restore_line_notes (b)
by real instructions all end up at the same address. I can find no
use for line number notes before other notes, so none are emitted. */
else if (GET_CODE (insn) != NOTE
+ && INSN_UID (insn) < old_max_uid
&& (note = LINE_NOTE (insn)) != 0
&& note != line
&& (line == 0
@@ -1341,7 +1339,7 @@ rm_redundant_line_notes ()
fprintf (sched_dump, ";; deleted %d line-number notes\n", notes);
}
-/* Delete notes between head and tail and put them in the chain
+/* Delete notes between HEAD and TAIL and put them in the chain
of notes ended by NOTE_LIST. */
void
@@ -1662,7 +1660,7 @@ schedule_block (b, rgn_n_insns)
fprintf (sched_dump, ";; ======================================================\n");
fprintf (sched_dump,
";; -- basic block %d from %d to %d -- %s reload\n",
- b, INSN_UID (BLOCK_HEAD (b)), INSN_UID (BLOCK_END (b)),
+ b, INSN_UID (head), INSN_UID (tail),
(reload_completed ? "after" : "before"));
fprintf (sched_dump, ";; ======================================================\n");
fprintf (sched_dump, "\n");
@@ -1682,7 +1680,7 @@ schedule_block (b, rgn_n_insns)
(*current_sched_info->init_ready_list) (&ready);
#ifdef MD_SCHED_INIT
- MD_SCHED_INIT (sched_dump, sched_verbose);
+ MD_SCHED_INIT (sched_dump, sched_verbose, ready.veclen);
#endif
/* No insns scheduled in this block yet. */
@@ -1712,6 +1710,11 @@ schedule_block (b, rgn_n_insns)
list. */
queue_to_ready (&ready);
+#ifdef HAVE_cycle_display
+ if (HAVE_cycle_display)
+ last = emit_insn_after (gen_cycle_display (GEN_INT (clock_var)), last);
+#endif
+
if (ready.n_ready == 0)
abort ();
@@ -1740,7 +1743,9 @@ schedule_block (b, rgn_n_insns)
}
/* Issue insns from ready list. */
- while (ready.n_ready != 0 && can_issue_more)
+ while (ready.n_ready != 0
+ && can_issue_more
+ && (*current_sched_info->schedule_more_p) ())
{
/* Select and remove the insn from the ready list. */
rtx insn = ready_remove_first (&ready);
@@ -1768,9 +1773,14 @@ schedule_block (b, rgn_n_insns)
schedule_insn (insn, &ready, clock_var);
next:
- /* Close this block after scheduling its jump. */
- if (GET_CODE (last_scheduled_insn) == JUMP_INSN)
- break;
+#ifdef MD_SCHED_REORDER2
+ /* Sort the ready list based on priority. */
+ if (ready.n_ready > 0)
+ ready_sort (&ready);
+ MD_SCHED_REORDER2 (sched_dump, sched_verbose,
+ ready.n_ready ? ready_lastpos (&ready) : NULL,
+ ready.n_ready, clock_var, can_issue_more);
+#endif
}
/* Debug info. */
@@ -1778,6 +1788,10 @@ schedule_block (b, rgn_n_insns)
visualize_scheduled_insns (clock_var);
}
+#ifdef MD_SCHED_FINISH
+ MD_SCHED_FINISH (sched_dump, sched_verbose);
+#endif
+
/* Debug info. */
if (sched_verbose)
{
@@ -1833,17 +1847,14 @@ schedule_block (b, rgn_n_insns)
/* Set_priorities: compute priority of each insn in the block. */
int
-set_priorities (b)
- int b;
+set_priorities (head, tail)
+ rtx head, tail;
{
rtx insn;
int n_insn;
- rtx tail;
rtx prev_head;
- rtx head;
- get_block_head_tail (b, &head, &tail);
prev_head = PREV_INSN (head);
if (head == tail && (! INSN_P (head)))
@@ -1936,12 +1947,23 @@ sched_init (dump_file)
determine the correct line number for the first insn of the block. */
for (b = 0; b < n_basic_blocks; b++)
- for (line = BLOCK_HEAD (b); line; line = PREV_INSN (line))
- if (GET_CODE (line) == NOTE && NOTE_LINE_NUMBER (line) > 0)
+ {
+ for (line = BLOCK_HEAD (b); line; line = PREV_INSN (line))
+ if (GET_CODE (line) == NOTE && NOTE_LINE_NUMBER (line) > 0)
+ {
+ line_note_head[b] = line;
+ break;
+ }
+ /* Do a forward search as well, since we won't get to see the first
+ notes in a basic block. */
+ for (line = BLOCK_HEAD (b); line; line = NEXT_INSN (line))
{
- line_note_head[b] = line;
- break;
+ if (INSN_P (line))
+ break;
+ if (GET_CODE (line) == NOTE && NOTE_LINE_NUMBER (line) > 0)
+ line_note_head[b] = line;
}
+ }
}
/* Find units used in this fuction, for visualization. */
Index: md.texi
===================================================================
RCS file: /cvs/gcc/egcs/gcc/md.texi,v
retrieving revision 1.52
diff -u -p -r1.52 md.texi
--- md.texi 2000/12/04 18:42:59 1.52
+++ md.texi 2000/12/19 17:15:56
@@ -2858,6 +2858,14 @@ A typical @code{conditional_trap} patter
"@dots{}")
@end smallexample
+@cindex @code{cycle_display} instruction pattern
+@item @samp{cycle_display}
+
+This pattern, if present, will be emitted by the instruction scheduler at
+the beginning of each new clock cycle. This can be used for annotating the
+assembler output with cycle counts. Operand 0 is a @code{const_int} that
+holds the clock cycle.
+
@end table
@node Pattern Ordering
Index: sched-deps.c
===================================================================
RCS file: /cvs/gcc/egcs/gcc/sched-deps.c,v
retrieving revision 1.1
diff -u -p -r1.1 sched-deps.c
--- sched-deps.c 2000/12/03 16:11:45 1.1
+++ sched-deps.c 2000/12/19 17:15:57
@@ -1327,6 +1327,9 @@ free_deps (deps)
if (deps->reg_last_uses[i])
free_INSN_LIST_list (&deps->reg_last_uses[i]);
}
+ free (deps->reg_last_clobbers);
+ free (deps->reg_last_sets);
+ free (deps->reg_last_uses);
}
/* If it is profitable to use them, initialize caches for tracking
Index: sched-int.h
===================================================================
RCS file: /cvs/gcc/egcs/gcc/sched-int.h,v
retrieving revision 1.3
diff -u -p -r1.3 sched-int.h
--- sched-int.h 2000/12/03 19:00:00 1.3
+++ sched-int.h 2000/12/19 17:15:58
@@ -252,14 +252,14 @@ extern void free_dependency_caches PARAM
extern void get_block_head_tail PARAMS ((int, rtx *, rtx *));
extern int no_real_insns_p PARAMS ((rtx, rtx));
-extern void rm_line_notes PARAMS ((int));
-extern void save_line_notes PARAMS ((int));
-extern void restore_line_notes PARAMS ((int));
+extern void rm_line_notes PARAMS ((rtx, rtx));
+extern void save_line_notes PARAMS ((int, rtx, rtx));
+extern void restore_line_notes PARAMS ((int, rtx, rtx));
extern void rm_redundant_line_notes PARAMS ((void));
extern void rm_other_notes PARAMS ((rtx, rtx));
extern int insn_issue_delay PARAMS ((rtx));
-extern int set_priorities PARAMS ((int));
+extern int set_priorities PARAMS ((rtx, rtx));
extern void schedule_block PARAMS ((int, int));
extern void sched_init PARAMS ((FILE *));
Index: sched-rgn.c
===================================================================
RCS file: /cvs/gcc/egcs/gcc/sched-rgn.c,v
retrieving revision 1.2
diff -u -p -r1.2 sched-rgn.c
--- sched-rgn.c 2000/12/05 16:51:13 1.2
+++ sched-rgn.c 2000/12/19 17:15:58
@@ -2032,6 +2032,8 @@ static int sched_target_n_insns;
static int target_n_insns;
/* The number of insns from the entire region scheduled so far. */
static int sched_n_insns;
+/* Nonzero if the last scheduled insn was a jump. */
+static int last_was_jump;
/* Implementations of the sched_info functions for region scheduling. */
static void init_ready_list PARAMS ((struct ready_list *));
@@ -2046,7 +2048,7 @@ static int rgn_rank PARAMS ((rtx, rtx));
static int
schedule_more_p ()
{
- return sched_target_n_insns < target_n_insns;
+ return ! last_was_jump && sched_target_n_insns < target_n_insns;
}
/* Add all insns that are initially ready to the ready list READY. Called
@@ -2064,6 +2066,7 @@ init_ready_list (ready)
target_n_insns = 0;
sched_target_n_insns = 0;
sched_n_insns = 0;
+ last_was_jump = 0;
/* Print debugging information. */
if (sched_verbose >= 5)
@@ -2155,6 +2158,9 @@ static int
can_schedule_ready_p (insn)
rtx insn;
{
+ if (GET_CODE (insn) == JUMP_INSN)
+ last_was_jump = 1;
+
/* An interblock motion? */
if (INSN_BB (insn) != target_bb)
{
@@ -2589,10 +2595,9 @@ compute_block_backward_dependences (bb)
/* Free up the INSN_LISTs. */
free_deps (&tmp_deps);
- /* Assert that we won't need bb_reg_last_* for this block anymore. */
- free (bb_deps[bb].reg_last_uses);
- free (bb_deps[bb].reg_last_sets);
- free (bb_deps[bb].reg_last_clobbers);
+ /* Assert that we won't need bb_reg_last_* for this block anymore.
+ The vectors we're zeroing out have just been freed by the call to
+ free_deps. */
bb_deps[bb].reg_last_uses = 0;
bb_deps[bb].reg_last_sets = 0;
bb_deps[bb].reg_last_clobbers = 0;
@@ -2726,7 +2731,12 @@ schedule_region (rgn)
/* Set priorities. */
for (bb = 0; bb < current_nr_blocks; bb++)
- rgn_n_insns += set_priorities (BB_TO_BLOCK (bb));
+ {
+ rtx head, tail;
+ get_block_head_tail (BB_TO_BLOCK (bb), &head, &tail);
+
+ rgn_n_insns += set_priorities (head, tail);
+ }
/* Compute interblock info: probabilities, split-edges, dominators, etc. */
if (current_nr_blocks > 1)
@@ -2788,8 +2798,8 @@ schedule_region (rgn)
if (write_symbols != NO_DEBUG)
{
- save_line_notes (b);
- rm_line_notes (b);
+ save_line_notes (b, head, tail);
+ rm_line_notes (head, tail);
}
/* rm_other_notes only removes notes which are _inside_ the
@@ -2855,7 +2865,11 @@ schedule_region (rgn)
if (write_symbols != NO_DEBUG)
{
for (bb = 0; bb < current_nr_blocks; bb++)
- restore_line_notes (BB_TO_BLOCK (bb));
+ {
+ rtx head, tail;
+ get_block_head_tail (BB_TO_BLOCK (bb), &head, &tail);
+ restore_line_notes (BB_TO_BLOCK (bb), head, tail);
+ }
}
/* Done with this region. */
Index: tm.texi
===================================================================
RCS file: /cvs/gcc/egcs/gcc/tm.texi,v
retrieving revision 1.155
diff -u -p -r1.155 tm.texi
--- tm.texi 2000/12/15 09:09:41 1.155
+++ tm.texi 2000/12/19 17:16:01
@@ -8134,11 +8134,22 @@ A C expression that returns how many ins
same time if the machine is a superscalar machine.
@findex MD_SCHED_INIT
-@item MD_SCHED_INIT (@var{file}, @var{verbose})
+@item MD_SCHED_INIT (@var{file}, @var{verbose}, @var{max_ready})
A C statement which is executed by the scheduler at the
beginning of each block of instructions that are to be scheduled.
@var{file} is either a null pointer, or a stdio stream to write any
debug output to. @var{verbose} is the verbose level provided by
+@samp{-fsched-verbose-}@var{n}. @var{max_ready} is the maximum number
+of insns in the current scheduling region that can be live at the same
+time. This can be used to allocate scratch space if it is needed.
+
+@findex MD_SCHED_FINISH
+@item MD_SCHED_FINISH (@var{file}, @var{verbose})
+A C statement which is executed by the scheduler at the end of each block
+of instructions that are to be scheduled. It can be used to perform
+cleanup of any actions done by the other scheduling macros.
+@var{file} is either a null pointer, or a stdio stream to write any
+debug output to. @var{verbose} is the verbose level provided by
@samp{-fsched-verbose-}@var{n}.
@findex MD_SCHED_REORDER
@@ -8155,7 +8166,18 @@ scheduler reads the ready list in revers
@var{ready}[@var{n_ready}-1] and going to @var{ready}[0]. @var{clock}
is the timer tick of the scheduler. @var{can_issue_more} is an output
parameter that is set to the number of insns that can issue this clock;
-normally this is just @code{issue_rate}.
+normally this is just @code{issue_rate}. See also @samp{MD_SCHED_REORDER2}.
+
+@findex MD_SCHED_REORDER2
+@item MD_SCHED_REORDER2 (@var{file}, @var{verbose}, @var{ready}, @var{n_ready}, @var{clock}, @var{can_issue_more})
+Like @samp{MD_SCHED_REORDER}, but called at a different time. While the
+@samp{MD_SCHED_REORDER} macro is called whenever the scheduler starts a
+new cycle, this macro is used immediately after @samp{MD_SCHED_VARIABLE_ISSUE}
+is called; it can reorder the ready list and set @var{can_issue_more} to
+determine whether there are more insns to be scheduled in the same cycle.
+Defining this macro can be useful if there are frequent situations where
+scheduling one insn causes other insns to become ready in the same cycle,
+these other insns can then be taken into account properly.
@findex MD_SCHED_VARIABLE_ISSUE
@item MD_SCHED_VARIABLE_ISSUE (@var{file}, @var{verbose}, @var{insn}, @var{more})
Index: config/i386/i386.h
===================================================================
RCS file: /cvs/gcc/egcs/gcc/config/i386/i386.h,v
retrieving revision 1.138
diff -u -p -r1.138 i386.h
--- config/i386/i386.h 2000/11/25 18:04:51 1.138
+++ config/i386/i386.h 2000/12/19 17:16:02
@@ -2462,7 +2462,7 @@ while (0)
#define ISSUE_RATE \
ix86_issue_rate ()
-#define MD_SCHED_INIT(DUMP, SCHED_VERBOSE) \
+#define MD_SCHED_INIT(DUMP, SCHED_VERBOSE, MAX_READY) \
ix86_sched_init (DUMP, SCHED_VERBOSE)
#define MD_SCHED_REORDER(DUMP, SCHED_VERBOSE, READY, N_READY, CLOCK, CIM) \
Index: config/m32r/m32r.h
===================================================================
RCS file: /cvs/gcc/egcs/gcc/config/m32r/m32r.h,v
retrieving revision 1.34
diff -u -p -r1.34 m32r.h
--- config/m32r/m32r.h 2000/11/02 23:29:10 1.34
+++ config/m32r/m32r.h 2000/12/19 17:16:03
@@ -1554,7 +1554,8 @@ do { \
extern int m32r_sched_odd_word_p;
/* Hook to run before scheduling a block of insns. */
-#define MD_SCHED_INIT(STREAM, VERBOSE) m32r_sched_init (STREAM, VERBOSE)
+#define MD_SCHED_INIT(STREAM, VERBOSE, MAX_READY) \
+ m32r_sched_init (STREAM, VERBOSE)
/* Hook to reorder the list of ready instructions. */
#define MD_SCHED_REORDER(STREAM, VERBOSE, READY, N_READY, CLOCK, CIM) \
Index: config/sparc/sparc.h
===================================================================
RCS file: /cvs/gcc/egcs/gcc/config/sparc/sparc.h,v
retrieving revision 1.125
diff -u -p -r1.125 sparc.h
--- config/sparc/sparc.h 2000/11/09 07:45:15 1.125
+++ config/sparc/sparc.h 2000/12/19 17:16:04
@@ -2897,7 +2897,7 @@ do {
#define ADJUST_COST(INSN,LINK,DEP,COST) \
(COST) = sparc_adjust_cost(INSN, LINK, DEP, COST)
-#define MD_SCHED_INIT(DUMP, SCHED_VERBOSE) \
+#define MD_SCHED_INIT(DUMP, SCHED_VERBOSE, MAX_READY) \
if (sparc_cpu == PROCESSOR_ULTRASPARC) \
ultrasparc_sched_init (DUMP, SCHED_VERBOSE)
More information about the Gcc-patches
mailing list