From e6c995451fa778c6d6afeae0ad8b735d4ccafb6e Mon Sep 17 00:00:00 2001
From: hubicka <hubicka@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Fri, 17 Aug 2001 13:45:59 +0000
Subject: [PATCH] * final.c: Undo my previous accidental checkin.
* output.h: Likewise. * tm.texi: Likewise.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@44960 138bc75d-0d04-0410-961f-82ee72b054a4
---
gcc/ChangeLog | 6 ++
gcc/doc/tm.texi | 20 ++----
gcc/final.c | 168 +++++++++++++++---------------------------------
gcc/output.h | 3 -
4 files changed, 64 insertions(+), 133 deletions(-)
diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 87a50a6fc393..1212a519ecfd 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+Fri Aug 17 15:41:35 CEST 2001 Jan Hubicka <jh@suse.cz>
+
+ * final.c: Undo my previous accidental checkin.
+ * output.h: Likewise.
+ * tm.texi: Likewise.
+
2001-08-16 Richard Henderson <rth@redhat.com>
* varasm.c (named_section_flags): Remove align parameter.
diff --git a/gcc/doc/tm.texi b/gcc/doc/tm.texi
index 1a99fc5564d6..538888b16d49 100644
--- a/gcc/doc/tm.texi
+++ b/gcc/doc/tm.texi
@@ -7137,20 +7137,6 @@ the target supports DWARF 2 frame unwind information.
This describes commands for alignment.
@table @code
-@findex JUMP_ALIGN_AFTER_BARRIER
-@item JUMP_ALIGN (@var{label})
-The alignment (log base 2) to put in front of @var{label}, which is
-a common destination of jumps and has no fallthru incomming edge.
-
-This macro need not be defined if you don't want any special alignment
-to be done at such a time. Most machine descriptions do not currently
-define the macro.
-
-Unless it's necessary to inspect the @var{label} parameter, it is better
-to set the variable @var{align_jumps} in the target's
-@code{OVERRIDE_OPTIONS}. Otherwise, you should try to honour the user's
-selection in @var{align_jumps} in a @code{JUMP_ALIGN} implementation.
-
@findex LABEL_ALIGN_AFTER_BARRIER
@item LABEL_ALIGN_AFTER_BARRIER (@var{label})
The alignment (log base 2) to put in front of @var{label}, which follows
@@ -7160,6 +7146,12 @@ This macro need not be defined if you don't want any special alignment
to be done at such a time. Most machine descriptions do not currently
define the macro.
+Unless it's necessary to inspect the @var{label} parameter, it is better
+to set the variable @var{align_jumps} in the target's
+@code{OVERRIDE_OPTIONS}. Otherwise, you should try to honour the user's
+selection in @var{align_jumps} in a @code{LABEL_ALIGN_AFTER_BARRIER}
+implementation.
+
@findex LABEL_ALIGN_AFTER_BARRIER_MAX_SKIP
@item LABEL_ALIGN_AFTER_BARRIER_MAX_SKIP
The maximum number of bytes to skip when applying
diff --git a/gcc/final.c b/gcc/final.c
index 821a814fa453..d32248196a00 100644
--- a/gcc/final.c
+++ b/gcc/final.c
@@ -632,6 +632,11 @@ static struct label_alignment *label_align;
void
init_insn_lengths ()
{
+ if (label_align)
+ {
+ free (label_align);
+ label_align = 0;
+ }
if (uid_shuid)
{
free (uid_shuid);
@@ -775,19 +780,11 @@ get_attr_length (insn)
#endif
#ifndef LABEL_ALIGN_AFTER_BARRIER
-#define LABEL_ALIGN_AFTER_BARRIER(LABEL) 1
+#define LABEL_ALIGN_AFTER_BARRIER(LABEL) align_jumps_log
#endif
#ifndef LABEL_ALIGN_AFTER_BARRIER_MAX_SKIP
-#define LABEL_ALIGN_AFTER_BARRIER_MAX_SKIP 0
-#endif
-
-#ifndef JUMP_ALIGN
-#define JUMP_ALIGN(LABEL) align_jumps_log
-#endif
-
-#ifndef JUMP_ALIGN_MAX_SKIP
-#define JUMP_ALIGN_MAX_SKIP (align_jumps-1)
+#define LABEL_ALIGN_AFTER_BARRIER_MAX_SKIP (align_jumps-1)
#endif
#ifndef ADDR_VEC_ALIGN
@@ -938,85 +935,6 @@ insn_current_reference_address (branch)
}
#endif /* HAVE_ATTR_length */
-void
-compute_alignments ()
-{
- int i;
- int log, max_skip, max_log;
-
- if (label_align)
- {
- free (label_align);
- label_align = 0;
- }
-
- max_labelno = max_label_num ();
- min_labelno = get_first_label_num ();
- label_align = (struct label_alignment *) xcalloc ((max_labelno - min_labelno + 1),
- sizeof (struct label_alignment));
-
- /* If not optimizing or optimizing for size, don't assign any alignments. */
- for (i = 0; i < n_basic_blocks; i++)
- {
- basic_block bb = BASIC_BLOCK (i);
- rtx label = bb->head;
- int fallthru_frequency = 0, branch_frequency = 0, has_fallthru = 0;
- edge e;
-
- if (GET_CODE (label) != CODE_LABEL)
- continue;
- max_log = LABEL_ALIGN (label);
- max_skip = LABEL_ALIGN_MAX_SKIP;
-
- for (e = bb->pred; e; e = e->pred_next)
- {
- if (e->flags & EDGE_FALLTHRU)
- has_fallthru = 1, fallthru_frequency += EDGE_FREQUENCY (e);
- else
- branch_frequency += EDGE_FREQUENCY (e);
- }
-
- /* There are two purposes to align block with no fallthru incomming edge:
- 1) to avoid fetch stalls when branch destination is near cache boundary
- 2) to improve cache effciency in case the previous block is not executed
- (so it does not need to be in the cache).
-
- We to catch first case, we align frequently executed blocks.
- To catch the second, we align blocks that are executed more frequently
- than the predecesor and the predecesor is likely to not be executed
- when function is called. */
-
- if (!has_fallthru
- && (branch_frequency > BB_FREQ_MAX / 10
- || (bb->frequency > BASIC_BLOCK (i - 1)->frequency * 10
- && (BASIC_BLOCK (i - 1)->frequency
- <= ENTRY_BLOCK_PTR->frequency / 2))))
- {
- log = JUMP_ALIGN (label);
- if (max_log < log)
- {
- max_log = log;
- max_skip = JUMP_ALIGN_MAX_SKIP;
- }
- }
- /* In case block is frequent and reached mostly by non-fallthru edge,
- align it. It is most likely an first block of loop. */
- if (has_fallthru
- && branch_frequency + fallthru_frequency > BB_FREQ_MAX / 10
- && branch_frequency > fallthru_frequency * 5)
- {
- log = LOOP_ALIGN (label);
- if (max_log < log)
- {
- max_log = log;
- max_skip = LOOP_ALIGN_MAX_SKIP;
- }
- }
- LABEL_TO_ALIGNMENT (label) = max_log;
- LABEL_TO_MAX_SKIP (label) = max_skip;
- }
-}
-
/* Make a pass over all insns and compute their actual lengths by shortening
any branches of variable length if possible. */
@@ -1054,29 +972,20 @@ shorten_branches (first)
#endif
- /* Compute maximum UID and allocate label_align / uid_shuid. */
- max_uid = get_max_uid ();
+ /* We must do some computations even when not actually shortening, in
+ order to get the alignment information for the labels. */
- uid_shuid = (int *) xmalloc (max_uid * sizeof *uid_shuid);
+ init_insn_lengths ();
- if (max_labelno != max_label_num ())
- {
- int old = max_labelno;
- int n_labels;
- int n_old_labels;
-
- max_labelno = max_label_num ();
-
- n_labels = max_labelno - min_labelno + 1;
- n_old_labels = old - min_labelno + 1;
+ /* Compute maximum UID and allocate label_align / uid_shuid. */
+ max_uid = get_max_uid ();
- label_align = (struct label_alignment *) xrealloc
- (label_align, n_labels * sizeof (struct label_alignment));
+ max_labelno = max_label_num ();
+ min_labelno = get_first_label_num ();
+ label_align = (struct label_alignment *)
+ xcalloc ((max_labelno - min_labelno + 1), sizeof (struct label_alignment));
- if (n_old_labels < n_labels)
- memset (label_align + n_old_labels, 0,
- (n_labels - n_old_labels) * sizeof (struct label_alignment));
- }
+ uid_shuid = (int *) xmalloc (max_uid * sizeof *uid_shuid);
/* Initialize label_align and set up uid_shuid to be strictly
monotonically rising with insn order. */
@@ -1103,14 +1012,6 @@ shorten_branches (first)
else if (GET_CODE (insn) == CODE_LABEL)
{
rtx next;
-
- /* Merge in alignments computed by compute_alignments. */
- log = LABEL_TO_ALIGNMENT (insn);
- if (max_log < log)
- {
- max_log = log;
- max_skip = LABEL_TO_MAX_SKIP (insn);
- }
log = LABEL_ALIGN (insn);
if (max_log < log)
@@ -1162,6 +1063,41 @@ shorten_branches (first)
break;
}
}
+ /* Again, we allow NOTE_INSN_LOOP_BEG - INSN - CODE_LABEL
+ sequences in order to handle reorg output efficiently. */
+ else if (GET_CODE (insn) == NOTE
+ && NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_BEG)
+ {
+ rtx label;
+ int nest = 0;
+
+ /* Search for the label that starts the loop.
+ Don't skip past the end of the loop, since that could
+ lead to putting an alignment where it does not belong.
+ However, a label after a nested (non-)loop would be OK. */
+ for (label = insn; label; label = NEXT_INSN (label))
+ {
+ if (GET_CODE (label) == NOTE
+ && NOTE_LINE_NUMBER (label) == NOTE_INSN_LOOP_BEG)
+ nest++;
+ else if (GET_CODE (label) == NOTE
+ && NOTE_LINE_NUMBER (label) == NOTE_INSN_LOOP_END
+ && --nest == 0)
+ break;
+ else if (GET_CODE (label) == CODE_LABEL)
+ {
+ log = LOOP_ALIGN (label);
+ if (max_log < log)
+ {
+ max_log = log;
+ max_skip = LOOP_ALIGN_MAX_SKIP;
+ }
+ break;
+ }
+ }
+ }
+ else
+ continue;
}
#ifdef HAVE_ATTR_length
diff --git a/gcc/output.h b/gcc/output.h
index 6b8ffbcd37b3..b5aea51efeda 100644
--- a/gcc/output.h
+++ b/gcc/output.h
@@ -20,9 +20,6 @@ along with GNU CC; see the file COPYING. If not, write to
the Free Software Foundation, 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
-/* Compute branch alignments based on frequency information in the CFG. */
-extern void compute_alignments PARAMS ((void));
-
/* Initialize data in final at the beginning of a compilation. */
extern void init_final PARAMS ((const char *));
--
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