Joern Rennecke wrote:
Doing only one update_life_info_in_dirty_blocks before the
crossjumping makes the compilation time go right back to 0.95
seconds. If that works, is another question... if there are any
transformations that invalidate global_live_at_end, we'll have to make
them update these regsets.
:ADDPATCH rtl-optimization:
In the previously posted patch, I used EXECUTE_IF_AND_IN_BITMAP, when I
really meant EXECUTE_IF_XOR_IN_BITMAP - except that that doesn't exist.
Replaced with bitmap_xor and EXECUTE_IF_SET_IN_BITMAP.
Testing also found one place where register live information
inconsistency came from: when cross-jumping succeeds, the
global_live_at_end set of the block that is made to jump into
the other block needs adjusting. There is a copy_reg_set which could
have done it, except it is done before the blocks are split, and the
blocks still contain the old instructions
with the different local registers. Hence split_block calculates an
incorrect new global_live_at_end for redirect_from.
Fixed by copying redirect_to->global_live_at_start into
redirect_from->global_live_at_end after the splits.
Moreover, I've found that update_life_info_in_dirty_blocks must not be
called while fake edges exist.
regression tested on i686-pc-linux-gnu native, X sh-elf and X sh64-elf.
2006-01-12 J"orn Rennecke <[EMAIL PROTECTED]>
* cfgcleanup.c: Reinstate patches for PR 20070
* struct-equiv.c (struct_equiv_regs_eq_p): New function.
(struct_equiv_init): Only call update_life_info_in_dirty_blocks
in order to initialize regsets if both blocks are dirty.
Make do sanity check of registers bening equal for STRUCT_EQUIV_FINAL.
Add new parameter check_regs_eq. Changed all callers.
* basic-block.h (struct_equiv_init): Update prototype.
* basic_block.h (STRUCT_EQUIV_SUSPEND_UPDATE): Define.
* struct-equiv.c (struct_equiv_regs_eq_p): Don't call
update_life_info_in_dirty_blocks if STRUCT_EQUIV_SUSPEND_UPDATE
is set in info->mode.
(struct_equiv_init): Likewise. Also, add sanity check of
global_live_at_end in that case.
* cfgcleanup.c (try_optimize_cfg): Call
update_life_info_in_dirty_blocks before start of loop. Set
STRUCT_EQUIV_SUSPEND_UPDATE in mode argument passed to
try_crossjump_bb.
(try_crossjump_to_edge): Set global_live_at_end of redirect_from
from global_live_at_start of redirect_to.
(outgoing_edges_match): Check number of edges before comparing
patterns.
Index: cfgcleanup.c
===================================================================
/usr/bin/diff -p -d -F^( -u -L cfgcleanup.c (revision 109499) -L
cfgcleanup.c (working copy) .svn/text-base/cfgcleanup.c.svn-base
cfgcleanup.c
--- cfgcleanup.c (revision 109499)
+++ cfgcleanup.c (working copy)
@@ -60,9 +60,7 @@ Software Foundation, 51 Franklin Street,
static bool first_pass;
static bool try_crossjump_to_edge (int, edge, edge);
static bool try_crossjump_bb (int, basic_block);
-static bool outgoing_edges_match (int, basic_block, basic_block);
-static int flow_find_cross_jump (int, basic_block, basic_block, rtx *, rtx *);
-static bool old_insns_match_p (int, rtx, rtx);
+static bool outgoing_edges_match (int *, struct equiv_info *);
static void merge_blocks_move_predecessor_nojumps (basic_block, basic_block);
static void merge_blocks_move_successor_nojumps (basic_block, basic_block);
@@ -74,7 +72,6 @@ static bool mark_effect (rtx, bitmap);
static void notice_new_block (basic_block);
static void update_forwarder_flag (basic_block);
static int mentions_nonequal_regs (rtx *, void *);
-static void merge_memattrs (rtx, rtx);
/* Set flags for newly created block. */
@@ -881,319 +878,6 @@ merge_blocks_move (edge e, basic_block b
return NULL;
}
-
-/* Removes the memory attributes of MEM expression
- if they are not equal. */
-
-void
-merge_memattrs (rtx x, rtx y)
-{
- int i;
- int j;
- enum rtx_code code;
- const char *fmt;
-
- if (x == y)
- return;
- if (x == 0 || y == 0)
- return;
-
- code = GET_CODE (x);
-
- if (code != GET_CODE (y))
- return;
-
- if (GET_MODE (x) != GET_MODE (y))
- return;
-
- if (code == MEM && MEM_ATTRS (x) != MEM_ATTRS (y))
- {
- if (! MEM_ATTRS (x))
- MEM_ATTRS (y) = 0;
- else if (! MEM_ATTRS (y))
- MEM_ATTRS (x) = 0;
- else
- {
- rtx mem_size;
-
- if (MEM_ALIAS_SET (x) != MEM_ALIAS_SET (y))
- {
- set_mem_alias_set (x, 0);
- set_mem_alias_set (y, 0);
- }
-
- if (! mem_expr_equal_p (MEM_EXPR (x), MEM_EXPR (y)))
- {
- set_mem_expr (x, 0);
- set_mem_expr (y, 0);
- set_mem_offset (x, 0);
- set_mem_offset (y, 0);
- }
- else if (MEM_OFFSET (x) != MEM_OFFSET (y))
- {
- set_mem_offset (x, 0);
- set_mem_offset (y, 0);
- }
-
- if (!MEM_SIZE (x))
- mem_size = NULL_RTX;
- else if (!MEM_SIZE (y))
- mem_size = NULL_RTX;
- else
- mem_size = GEN_INT (MAX (INTVAL (MEM_SIZE (x)),
- INTVAL (MEM_SIZE (y))));
- set_mem_size (x, mem_size);
- set_mem_size (y, mem_size);
-
- set_mem_align (x, MIN (MEM_ALIGN (x), MEM_ALIGN (y)));
- set_mem_align (y, MEM_ALIGN (x));
- }
- }
-
- fmt = GET_RTX_FORMAT (code);
- for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
- {
- switch (fmt[i])
- {
- case 'E':
- /* Two vectors must have the same length. */
- if (XVECLEN (x, i) != XVECLEN (y, i))
- return;
-
- for (j = 0; j < XVECLEN (x, i); j++)
- merge_memattrs (XVECEXP (x, i, j), XVECEXP (y, i, j));
-
- break;
-
- case 'e':
- merge_memattrs (XEXP (x, i), XEXP (y, i));
- }
- }
- return;
-}
-
-
-/* Return true if I1 and I2 are equivalent and thus can be crossjumped. */
-
-static bool
-old_insns_match_p (int mode ATTRIBUTE_UNUSED, rtx i1, rtx i2)
-{
- rtx p1, p2;
-
- /* Verify that I1 and I2 are equivalent. */
- if (GET_CODE (i1) != GET_CODE (i2))
- return false;
-
- p1 = PATTERN (i1);
- p2 = PATTERN (i2);
-
- if (GET_CODE (p1) != GET_CODE (p2))
- return false;
-
- /* If this is a CALL_INSN, compare register usage information.
- If we don't check this on stack register machines, the two
- CALL_INSNs might be merged leaving reg-stack.c with mismatching
- numbers of stack registers in the same basic block.
- If we don't check this on machines with delay slots, a delay slot may
- be filled that clobbers a parameter expected by the subroutine.
-
- ??? We take the simple route for now and assume that if they're
- equal, they were constructed identically. */
-
- if (CALL_P (i1)
- && (!rtx_equal_p (CALL_INSN_FUNCTION_USAGE (i1),
- CALL_INSN_FUNCTION_USAGE (i2))
- || SIBLING_CALL_P (i1) != SIBLING_CALL_P (i2)))
- return false;
-
-#ifdef STACK_REGS
- /* If cross_jump_death_matters is not 0, the insn's mode
- indicates whether or not the insn contains any stack-like
- regs. */
-
- if ((mode & CLEANUP_POST_REGSTACK) && stack_regs_mentioned (i1))
- {
- /* If register stack conversion has already been done, then
- death notes must also be compared before it is certain that
- the two instruction streams match. */
-
- rtx note;
- HARD_REG_SET i1_regset, i2_regset;
-
- CLEAR_HARD_REG_SET (i1_regset);
- CLEAR_HARD_REG_SET (i2_regset);
-
- for (note = REG_NOTES (i1); note; note = XEXP (note, 1))
- if (REG_NOTE_KIND (note) == REG_DEAD && STACK_REG_P (XEXP (note, 0)))
- SET_HARD_REG_BIT (i1_regset, REGNO (XEXP (note, 0)));
-
- for (note = REG_NOTES (i2); note; note = XEXP (note, 1))
- if (REG_NOTE_KIND (note) == REG_DEAD && STACK_REG_P (XEXP (note, 0)))
- SET_HARD_REG_BIT (i2_regset, REGNO (XEXP (note, 0)));
-
- GO_IF_HARD_REG_EQUAL (i1_regset, i2_regset, done);
-
- return false;
-
- done:
- ;
- }
-#endif
-
- if (reload_completed
- ? rtx_renumbered_equal_p (p1, p2) : rtx_equal_p (p1, p2))
- return true;
-
- /* Do not do EQUIV substitution after reload. First, we're undoing the
- work of reload_cse. Second, we may be undoing the work of the post-
- reload splitting pass. */
- /* ??? Possibly add a new phase switch variable that can be used by
- targets to disallow the troublesome insns after splitting. */
- if (!reload_completed)
- {
- /* The following code helps take care of G++ cleanups. */
- rtx equiv1 = find_reg_equal_equiv_note (i1);
- rtx equiv2 = find_reg_equal_equiv_note (i2);
-
- if (equiv1 && equiv2
- /* If the equivalences are not to a constant, they may
- reference pseudos that no longer exist, so we can't
- use them. */
- && (! reload_completed
- || (CONSTANT_P (XEXP (equiv1, 0))
- && rtx_equal_p (XEXP (equiv1, 0), XEXP (equiv2, 0)))))
- {
- rtx s1 = single_set (i1);
- rtx s2 = single_set (i2);
- if (s1 != 0 && s2 != 0
- && rtx_renumbered_equal_p (SET_DEST (s1), SET_DEST (s2)))
- {
- validate_change (i1, &SET_SRC (s1), XEXP (equiv1, 0), 1);
- validate_change (i2, &SET_SRC (s2), XEXP (equiv2, 0), 1);
- if (! rtx_renumbered_equal_p (p1, p2))
- cancel_changes (0);
- else if (apply_change_group ())
- return true;
- }
- }
- }
-
- return false;
-}
-
-/* Look through the insns at the end of BB1 and BB2 and find the longest
- sequence that are equivalent. Store the first insns for that sequence
- in *F1 and *F2 and return the sequence length.
-
- To simplify callers of this function, if the blocks match exactly,
- store the head of the blocks in *F1 and *F2. */
-
-static int
-flow_find_cross_jump (int mode ATTRIBUTE_UNUSED, basic_block bb1,
- basic_block bb2, rtx *f1, rtx *f2)
-{
- rtx i1, i2, last1, last2, afterlast1, afterlast2;
- int ninsns = 0;
-
- /* Skip simple jumps at the end of the blocks. Complex jumps still
- need to be compared for equivalence, which we'll do below. */
-
- i1 = BB_END (bb1);
- last1 = afterlast1 = last2 = afterlast2 = NULL_RTX;
- if (onlyjump_p (i1)
- || (returnjump_p (i1) && !side_effects_p (PATTERN (i1))))
- {
- last1 = i1;
- i1 = PREV_INSN (i1);
- }
-
- i2 = BB_END (bb2);
- if (onlyjump_p (i2)
- || (returnjump_p (i2) && !side_effects_p (PATTERN (i2))))
- {
- last2 = i2;
- /* Count everything except for unconditional jump as insn. */
- if (!simplejump_p (i2) && !returnjump_p (i2) && last1)
- ninsns++;
- i2 = PREV_INSN (i2);
- }
-
- while (true)
- {
- /* Ignore notes. */
- while (!INSN_P (i1) && i1 != BB_HEAD (bb1))
- i1 = PREV_INSN (i1);
-
- while (!INSN_P (i2) && i2 != BB_HEAD (bb2))
- i2 = PREV_INSN (i2);
-
- if (i1 == BB_HEAD (bb1) || i2 == BB_HEAD (bb2))
- break;
-
- if (!old_insns_match_p (mode, i1, i2))
- break;
-
- merge_memattrs (i1, i2);
-
- /* Don't begin a cross-jump with a NOTE insn. */
- if (INSN_P (i1))
- {
- /* If the merged insns have different REG_EQUAL notes, then
- remove them. */
- rtx equiv1 = find_reg_equal_equiv_note (i1);
- rtx equiv2 = find_reg_equal_equiv_note (i2);
-
- if (equiv1 && !equiv2)
- remove_note (i1, equiv1);
- else if (!equiv1 && equiv2)
- remove_note (i2, equiv2);
- else if (equiv1 && equiv2
- && !rtx_equal_p (XEXP (equiv1, 0), XEXP (equiv2, 0)))
- {
- remove_note (i1, equiv1);
- remove_note (i2, equiv2);
- }
-
- afterlast1 = last1, afterlast2 = last2;
- last1 = i1, last2 = i2;
- ninsns++;
- }
-
- i1 = PREV_INSN (i1);
- i2 = PREV_INSN (i2);
- }
-
-#ifdef HAVE_cc0
- /* Don't allow the insn after a compare to be shared by
- cross-jumping unless the compare is also shared. */
- if (ninsns && reg_mentioned_p (cc0_rtx, last1) && ! sets_cc0_p (last1))
- last1 = afterlast1, last2 = afterlast2, ninsns--;
-#endif
-
- /* Include preceding notes and labels in the cross-jump. One,
- this may bring us to the head of the blocks as requested above.
- Two, it keeps line number notes as matched as may be. */
- if (ninsns)
- {
- while (last1 != BB_HEAD (bb1) && !INSN_P (PREV_INSN (last1)))
- last1 = PREV_INSN (last1);
-
- if (last1 != BB_HEAD (bb1) && LABEL_P (PREV_INSN (last1)))
- last1 = PREV_INSN (last1);
-
- while (last2 != BB_HEAD (bb2) && !INSN_P (PREV_INSN (last2)))
- last2 = PREV_INSN (last2);
-
- if (last2 != BB_HEAD (bb2) && LABEL_P (PREV_INSN (last2)))
- last2 = PREV_INSN (last2);
-
- *f1 = last1;
- *f2 = last2;
- }
-
- return ninsns;
-}
-
/* Return true iff the condbranches at the end of BB1 and BB2 match. */
bool
condjump_equiv_p (struct equiv_info *info, bool call_init)
@@ -1252,8 +936,8 @@ condjump_equiv_p (struct equiv_info *inf
if (code2 == UNKNOWN)
return false;
- if (call_init && !struct_equiv_init (STRUCT_EQUIV_START | info->mode, info))
- gcc_unreachable ();
+ if (call_init)
+ struct_equiv_init (STRUCT_EQUIV_START | info->mode, info, false);
/* Make the sources of the pc sets unreadable so that when we call
insns_match_p it won't process them.
The death_notes_match_p from insns_match_p won't see the local registers
@@ -1322,15 +1006,20 @@ condjump_equiv_p (struct equiv_info *inf
return match;
}
-/* Return true iff outgoing edges of BB1 and BB2 match, together with
- the branch instruction. This means that if we commonize the control
- flow before end of the basic block, the semantic remains unchanged.
+/* Return true iff outgoing edges of INFO->y_block and INFO->x_block match,
+ together with the branch instruction. This means that if we commonize the
+ control flow before end of the basic block, the semantic remains unchanged.
+ If we need to compare jumps, we set STRUCT_EQUIV_MATCH_JUMPS in *MODE,
+ and pass *MODE to struct_equiv_init or assign it to INFO->mode, as
+ appropriate.
We may assume that there exists one edge with a common destination. */
static bool
-outgoing_edges_match (int mode, basic_block bb1, basic_block bb2)
+outgoing_edges_match (int *mode, struct equiv_info *info)
{
+ basic_block bb1 = info->y_block;
+ basic_block bb2 = info->x_block;
int nehedges1 = 0, nehedges2 = 0;
edge fallthru1 = 0, fallthru2 = 0;
edge e1, e2;
@@ -1346,114 +1035,19 @@ outgoing_edges_match (int mode, basic_bl
& (EDGE_COMPLEX | EDGE_FAKE)) == 0
&& (!JUMP_P (BB_END (bb2)) || simplejump_p (BB_END (bb2))));
+ *mode |= STRUCT_EQUIV_MATCH_JUMPS;
/* Match conditional jumps - this may get tricky when fallthru and branch
edges are crossed. */
if (EDGE_COUNT (bb1->succs) == 2
&& any_condjump_p (BB_END (bb1))
&& onlyjump_p (BB_END (bb1)))
{
- edge b1, f1, b2, f2;
- bool reverse, match;
- rtx set1, set2, cond1, cond2;
- enum rtx_code code1, code2;
-
if (EDGE_COUNT (bb2->succs) != 2
|| !any_condjump_p (BB_END (bb2))
|| !onlyjump_p (BB_END (bb2)))
return false;
-
- b1 = BRANCH_EDGE (bb1);
- b2 = BRANCH_EDGE (bb2);
- f1 = FALLTHRU_EDGE (bb1);
- f2 = FALLTHRU_EDGE (bb2);
-
- /* Get around possible forwarders on fallthru edges. Other cases
- should be optimized out already. */
- if (FORWARDER_BLOCK_P (f1->dest))
- f1 = single_succ_edge (f1->dest);
-
- if (FORWARDER_BLOCK_P (f2->dest))
- f2 = single_succ_edge (f2->dest);
-
- /* To simplify use of this function, return false if there are
- unneeded forwarder blocks. These will get eliminated later
- during cleanup_cfg. */
- if (FORWARDER_BLOCK_P (f1->dest)
- || FORWARDER_BLOCK_P (f2->dest)
- || FORWARDER_BLOCK_P (b1->dest)
- || FORWARDER_BLOCK_P (b2->dest))
- return false;
-
- if (f1->dest == f2->dest && b1->dest == b2->dest)
- reverse = false;
- else if (f1->dest == b2->dest && b1->dest == f2->dest)
- reverse = true;
- else
- return false;
-
- set1 = pc_set (BB_END (bb1));
- set2 = pc_set (BB_END (bb2));
- if ((XEXP (SET_SRC (set1), 1) == pc_rtx)
- != (XEXP (SET_SRC (set2), 1) == pc_rtx))
- reverse = !reverse;
-
- cond1 = XEXP (SET_SRC (set1), 0);
- cond2 = XEXP (SET_SRC (set2), 0);
- code1 = GET_CODE (cond1);
- if (reverse)
- code2 = reversed_comparison_code (cond2, BB_END (bb2));
- else
- code2 = GET_CODE (cond2);
-
- if (code2 == UNKNOWN)
- return false;
-
- /* Verify codes and operands match. */
- match = ((code1 == code2
- && rtx_renumbered_equal_p (XEXP (cond1, 0), XEXP (cond2, 0))
- && rtx_renumbered_equal_p (XEXP (cond1, 1), XEXP (cond2, 1)))
- || (code1 == swap_condition (code2)
- && rtx_renumbered_equal_p (XEXP (cond1, 1),
- XEXP (cond2, 0))
- && rtx_renumbered_equal_p (XEXP (cond1, 0),
- XEXP (cond2, 1))));
-
- /* If we return true, we will join the blocks. Which means that
- we will only have one branch prediction bit to work with. Thus
- we require the existing branches to have probabilities that are
- roughly similar. */
- if (match
- && !optimize_size
- && maybe_hot_bb_p (bb1)
- && maybe_hot_bb_p (bb2))
- {
- int prob2;
-
- if (b1->dest == b2->dest)
- prob2 = b2->probability;
- else
- /* Do not use f2 probability as f2 may be forwarded. */
- prob2 = REG_BR_PROB_BASE - b2->probability;
-
- /* Fail if the difference in probabilities is greater than 50%.
- This rules out two well-predicted branches with opposite
- outcomes. */
- if (abs (b1->probability - prob2) > REG_BR_PROB_BASE / 2)
- {
- if (dump_file)
- fprintf (dump_file,
- "Outcomes of branch in bb %i and %i differ too much
(%i %i)\n",
- bb1->index, bb2->index, b1->probability, prob2);
-
- return false;
- }
- }
-
- if (dump_file && match)
- fprintf (dump_file, "Conditionals in bb %i and %i match.\n",
- bb1->index, bb2->index);
-
- return match;
+ info->mode = *mode;
+ return condjump_equiv_p (info, true);
}
/* Generic case - we are seeing a computed jump, table jump or trapping
@@ -1501,31 +1095,22 @@ outgoing_edges_match (int mode, basic_bl
identical = false;
}
- if (identical)
+ if (identical
+ && struct_equiv_init (STRUCT_EQUIV_START | *mode, info, true))
{
- replace_label_data rr;
bool match;
- /* Temporarily replace references to LABEL1 with LABEL2
+ /* Indicate that LABEL1 is to be replaced with LABEL2
in BB1->END so that we could compare the instructions. */
- rr.r1 = label1;
- rr.r2 = label2;
- rr.update_label_nuses = false;
- for_each_rtx (&BB_END (bb1), replace_label, &rr);
+ info->y_label = label1;
+ info->x_label = label2;
- match = old_insns_match_p (mode, BB_END (bb1), BB_END (bb2));
+ match = insns_match_p (BB_END (bb1), BB_END (bb2), info);
if (dump_file && match)
fprintf (dump_file,
"Tablejumps in bb %i and %i match.\n",
bb1->index, bb2->index);
- /* Set the original label in BB1->END because when deleting
- a block whose end is a tablejump, the tablejump referenced
- from the instruction is deleted too. */
- rr.r1 = label2;
- rr.r2 = label1;
- for_each_rtx (&BB_END (bb1), replace_label, &rr);
-
return match;
}
}
@@ -1533,16 +1118,20 @@ outgoing_edges_match (int mode, basic_bl
}
}
+ /* Ensure that the edge counts do match. */
+ if (EDGE_COUNT (bb1->succs) != EDGE_COUNT (bb2->succs))
+ return false;
+
/* First ensure that the instructions match. There may be many outgoing
edges so this test is generally cheaper. */
- if (!old_insns_match_p (mode, BB_END (bb1), BB_END (bb2)))
+ /* FIXME: the regset compare might be costly. We should try to get a cheap
+ and reasonably effective test first. */
+ if (!struct_equiv_init (STRUCT_EQUIV_START | *mode, info, true)
+ || !insns_match_p (BB_END (bb1), BB_END (bb2), info))
return false;
- /* Search the outgoing edges, ensure that the counts do match, find possible
- fallthru and exception handling edges since these needs more
- validation. */
- if (EDGE_COUNT (bb1->succs) != EDGE_COUNT (bb2->succs))
- return false;
+ /* Search the outgoing edges, find possible fallthru and exception
+ handling edges since these needs more validation. */
FOR_EACH_EDGE (e1, ei, bb1->succs)
{
@@ -1601,22 +1190,21 @@ outgoing_edges_match (int mode, basic_bl
static bool
try_crossjump_to_edge (int mode, edge e1, edge e2)
{
- int nmatch;
+ int nmatch, i;
basic_block src1 = e1->src, src2 = e2->src;
basic_block redirect_to, redirect_from, to_remove;
- rtx newpos1, newpos2;
edge s;
edge_iterator ei;
-
- newpos1 = newpos2 = NULL_RTX;
+ struct equiv_info info;
+ rtx x_active, y_active;
/* If we have partitioned hot/cold basic blocks, it is a bad idea
- to try this optimization.
+ to try this optimization.
Basic block partitioning may result in some jumps that appear to
- be optimizable (or blocks that appear to be mergeable), but which really
- must be left untouched (they are required to make it safely across
- partition boundaries). See the comments at the top of
+ be optimizable (or blocks that appear to be mergeable), but which really
+ must be left untouched (they are required to make it safely across
+ partition boundaries). See the comments at the top of
bb-reorder.c:partition_hot_cold_basic_blocks for complete details. */
if (flag_reorder_blocks_and_partition && no_new_pseudos)
@@ -1655,20 +1243,67 @@ try_crossjump_to_edge (int mode, edge e1
return false;
/* Look for the common insn sequence, part the first ... */
- if (!outgoing_edges_match (mode, src1, src2))
+ info.x_block = src2;
+ info.y_block = src1;
+ if (!outgoing_edges_match (&mode, &info))
return false;
/* ... and part the second. */
- nmatch = flow_find_cross_jump (mode, src1, src2, &newpos1, &newpos2);
+ info.input_cost = optimize_size ? COSTS_N_INSNS (1) : -1;
+ nmatch = struct_equiv_block_eq (STRUCT_EQUIV_START | mode, &info);
/* Don't proceed with the crossjump unless we found a sufficient number
of matching instructions or the 'from' block was totally matched
(such that its predecessors will hopefully be redirected and the
block removed). */
- if ((nmatch < PARAM_VALUE (PARAM_MIN_CROSSJUMP_INSNS))
- && (newpos1 != BB_HEAD (src1)))
+ if (!nmatch)
+ return false;
+ if ((nmatch -info.cur.input_count < PARAM_VALUE (PARAM_MIN_CROSSJUMP_INSNS))
+ && (info.cur.y_start != BB_HEAD (src1)))
+ return false;
+ while (info.need_rerun)
+ {
+ nmatch = struct_equiv_block_eq (STRUCT_EQUIV_RERUN | mode, &info);
+ if (!nmatch)
+ return false;
+ if ((nmatch -info.cur.input_count < PARAM_VALUE
(PARAM_MIN_CROSSJUMP_INSNS))
+ && (info.cur.y_start != BB_HEAD (src1)))
+ return false;
+ }
+ nmatch = struct_equiv_block_eq (STRUCT_EQUIV_FINAL | mode, &info);
+ if ((nmatch -info.cur.input_count < PARAM_VALUE (PARAM_MIN_CROSSJUMP_INSNS))
+ && (info.cur.y_start != BB_HEAD (src1)))
return false;
+ /* Skip possible basic block header. */
+ x_active = info.cur.x_start;
+ if (LABEL_P (x_active))
+ x_active = NEXT_INSN (x_active);
+ if (NOTE_P (x_active))
+ x_active = NEXT_INSN (x_active);
+
+ y_active = info.cur.y_start;
+ if (LABEL_P (y_active))
+ y_active = NEXT_INSN (y_active);
+ if (NOTE_P (y_active))
+ y_active = NEXT_INSN (y_active);
+
+ /* In order for this code to become active, either we have to be called
+ before reload, or struct_equiv_block_eq needs to add register scavenging
+ code to allocate input_reg after reload. */
+ if (info.input_reg)
+ {
+ emit_insn_before (gen_move_insn (info.input_reg, info.x_input),
+ x_active);
+ emit_insn_before (gen_move_insn (info.input_reg, info.y_input),
+ y_active);
+ }
+
+ for (i = 0; i < info.cur.local_count; i++)
+ if (info.local_rvalue[i])
+ emit_insn_before (gen_move_insn (info.x_local[i], info.y_local[i]),
+ y_active);
+
/* Here we know that the insns in the end of SRC1 which are common with SRC2
will be deleted.
If we have tablejumps in the end of SRC1 and SRC2
@@ -1703,30 +1338,34 @@ try_crossjump_to_edge (int mode, edge e1
/* Avoid splitting if possible. We must always split when SRC2 has
EH predecessor edges, or we may end up with basic blocks with both
normal and EH predecessor edges. */
- if (newpos2 == BB_HEAD (src2)
+ if (info.cur.x_start == BB_HEAD (src2)
&& !(EDGE_PRED (src2, 0)->flags & EDGE_EH))
redirect_to = src2;
else
{
- if (newpos2 == BB_HEAD (src2))
+ if (info.cur.x_start == BB_HEAD (src2))
{
/* Skip possible basic block header. */
- if (LABEL_P (newpos2))
- newpos2 = NEXT_INSN (newpos2);
- if (NOTE_P (newpos2))
- newpos2 = NEXT_INSN (newpos2);
+ if (LABEL_P (info.cur.x_start))
+ info.cur.x_start = NEXT_INSN (info.cur.x_start);
+ if (NOTE_P (info.cur.x_start))
+ info.cur.x_start = NEXT_INSN (info.cur.x_start);
}
if (dump_file)
fprintf (dump_file, "Splitting bb %i before %i insns\n",
src2->index, nmatch);
- redirect_to = split_block (src2, PREV_INSN (newpos2))->dest;
+ redirect_to = split_block (src2, PREV_INSN (info.cur.x_start))->dest;
}
if (dump_file)
- fprintf (dump_file,
- "Cross jumping from bb %i to bb %i; %i common insns\n",
- src1->index, src2->index, nmatch);
+ {
+ fprintf (dump_file, "Cross jumping from bb %i to bb %i; %i common insns",
+ src1->index, src2->index, nmatch);
+ if (info.cur.local_count)
+ fprintf (dump_file, ", %i local registers", info.cur.local_count);
+ fprintf (dump_file, "\n");
+ }
redirect_to->count += src1->count;
redirect_to->frequency += src1->frequency;
@@ -1790,17 +1429,12 @@ try_crossjump_to_edge (int mode, edge e1
/* Edit SRC1 to go to REDIRECT_TO at NEWPOS1. */
- /* Skip possible basic block header. */
- if (LABEL_P (newpos1))
- newpos1 = NEXT_INSN (newpos1);
-
- if (NOTE_P (newpos1))
- newpos1 = NEXT_INSN (newpos1);
-
- redirect_from = split_block (src1, PREV_INSN (newpos1))->src;
+ redirect_from = split_block (src1, PREV_INSN (y_active))->src;
to_remove = single_succ (redirect_from);
redirect_edge_and_branch_force (single_succ_edge (redirect_from),
redirect_to);
+ COPY_REG_SET (redirect_from->il.rtl->global_live_at_end,
+ redirect_to->il.rtl->global_live_at_start);
delete_basic_block (to_remove);
update_forwarder_flag (redirect_from);
@@ -1957,9 +1591,22 @@ try_optimize_cfg (int mode)
bool changed;
int iterations = 0;
basic_block bb, b, next;
+ bool can_modify_jumps = ! targetm.cannot_modify_jumps_p ();
+ bool do_crossjump = false;
- if (mode & CLEANUP_CROSSJUMP)
- add_noreturn_fake_exit_edges ();
+ if (can_modify_jumps && (mode & CLEANUP_CROSSJUMP))
+ {
+ do_crossjump = true;
+ /* Life info updates malfunction in the presence of fake edges.
+ If we want to do any updates while fake edges are present, we'll have
+ to make sure to exclude them when recomputing global_live_at_end,
+ or treat them like EH edges. */
+ update_life_info_in_dirty_blocks (UPDATE_LIFE_GLOBAL_RM_NOTES,
+ (PROP_DEATH_NOTES
+ | ((mode & CLEANUP_POST_REGSTACK)
+ ? PROP_POST_REGSTACK : 0)));
+ add_noreturn_fake_exit_edges ();
+ }
if (mode & (CLEANUP_UPDATE_LIFE | CLEANUP_CROSSJUMP | CLEANUP_THREADING))
clear_bb_flags ();
@@ -1967,7 +1614,7 @@ try_optimize_cfg (int mode)
FOR_EACH_BB (bb)
update_forwarder_flag (bb);
- if (! targetm.cannot_modify_jumps_p ())
+ if (can_modify_jumps)
{
first_pass = true;
/* Attempt to merge blocks as made possible by edge removal. If
@@ -2123,8 +1770,8 @@ try_optimize_cfg (int mode)
changed_here = true;
/* Look for shared code between blocks. */
- if ((mode & CLEANUP_CROSSJUMP)
- && try_crossjump_bb (mode, b))
+ if (do_crossjump
+ && try_crossjump_bb (mode | STRUCT_EQUIV_SUSPEND_UPDATES, b))
changed_here = true;
/* Don't get confused by the index shift caused by
@@ -2135,8 +1782,9 @@ try_optimize_cfg (int mode)
changed = true;
}
- if ((mode & CLEANUP_CROSSJUMP)
- && try_crossjump_bb (mode, EXIT_BLOCK_PTR))
+ if (do_crossjump
+ && try_crossjump_bb (mode | STRUCT_EQUIV_SUSPEND_UPDATES,
+ EXIT_BLOCK_PTR))
changed = true;
#ifdef ENABLE_CHECKING
@@ -2150,7 +1798,7 @@ try_optimize_cfg (int mode)
while (changed);
}
- if (mode & CLEANUP_CROSSJUMP)
+ if (do_crossjump)
remove_fake_exit_edges ();
FOR_ALL_BB (b)
Index: basic-block.h
===================================================================
/usr/bin/diff -p -d -F^( -u -L basic-block.h (revision 109499) -L
basic-block.h (working copy) .svn/text-base/basic-block.h.svn-base
basic-block.h
--- basic-block.h (revision 109499)
+++ basic-block.h (working copy)
@@ -850,6 +850,8 @@ enum update_life_extent
to match only full blocks */
#define STRUCT_EQUIV_MATCH_JUMPS 8192 /* Also include the jumps at the end of
the block in the comparison. */
+#define STRUCT_EQUIV_SUSPEND_UPDATES 16384 /* Assume global_live_at_end is
up-to-date even if the block isn't. */
+
extern void life_analysis (FILE *, int);
extern int update_life_info (sbitmap, enum update_life_extent, int);
extern int update_life_info_in_dirty_blocks (enum update_life_extent, int);
@@ -1169,7 +1171,7 @@ struct equiv_info
extern bool insns_match_p (rtx, rtx, struct equiv_info *);
extern int struct_equiv_block_eq (int, struct equiv_info *);
-extern bool struct_equiv_init (int, struct equiv_info *);
+extern bool struct_equiv_init (int, struct equiv_info *, bool);
extern bool rtx_equiv_p (rtx *, rtx, int, struct equiv_info *);
/* In cfgrtl.c */
Index: struct-equiv.c
===================================================================
/usr/bin/diff -p -d -F^( -u -L struct-equiv.c (revision 109668) -L
struct-equiv.c (working copy) .svn/text-base/struct-equiv.c.svn-base
struct-equiv.c
--- struct-equiv.c (revision 109668)
+++ struct-equiv.c (working copy)
@@ -987,38 +987,59 @@ insns_match_p (rtx i1, rtx i2, struct eq
return false;
}
-/* Set up mode and register information in INFO. Return true for success. */
-bool
-struct_equiv_init (int mode, struct equiv_info *info)
+static bool
+struct_equiv_regs_eq_p (struct equiv_info *info)
{
- if ((info->x_block->flags | info->y_block->flags) & BB_DIRTY)
+ if (!(info->mode & STRUCT_EQUIV_SUSPEND_UPDATES)
+ && ((info->x_block->flags | info->y_block->flags) & BB_DIRTY))
update_life_info_in_dirty_blocks (UPDATE_LIFE_GLOBAL_RM_NOTES,
(PROP_DEATH_NOTES
- | ((mode & CLEANUP_POST_REGSTACK)
+ | ((info->mode & CLEANUP_POST_REGSTACK)
? PROP_POST_REGSTACK : 0)));
- if (!REG_SET_EQUAL_P (info->x_block->il.rtl->global_live_at_end,
- info->y_block->il.rtl->global_live_at_end))
- {
#ifdef STACK_REGS
- unsigned rn;
+ if (info->mode & CLEANUP_POST_REGSTACK)
+ {
+ regset_head diff;
+ unsigned regnum;
+ bitmap_iterator rsi;
- if (!(mode & CLEANUP_POST_REGSTACK))
- return false;
- /* After reg-stack. Remove bogus live info about stack regs. N.B.
- these regs are not necessarily all dead - we swap random bogosity
- against constant bogosity. However, clearing these bits at
- least makes the regsets comparable. */
- for (rn = FIRST_STACK_REG; rn <= LAST_STACK_REG; rn++)
+ INIT_REG_SET (&diff);
+ bitmap_xor (&diff,
+ info->x_block->il.rtl->global_live_at_end,
+ info->y_block->il.rtl->global_live_at_end);
+ EXECUTE_IF_SET_IN_BITMAP (&diff, 0, regnum, rsi)
{
- CLEAR_REGNO_REG_SET (info->x_block->il.rtl->global_live_at_end, rn);
- CLEAR_REGNO_REG_SET (info->y_block->il.rtl->global_live_at_end, rn);
+ if (regnum < FIRST_STACK_REG || regnum > LAST_STACK_REG)
+ return false;
}
- if (!REG_SET_EQUAL_P (info->x_block->il.rtl->global_live_at_end,
- info->y_block->il.rtl->global_live_at_end))
+ return true;
+ }
#endif
+ return (REG_SET_EQUAL_P (info->x_block->il.rtl->global_live_at_end,
+ info->y_block->il.rtl->global_live_at_end));
+}
+
+/* Set up mode and register information in INFO. Return true for success.
+ Nonzero CHECK_REGS_EQ indicates that we might be called with blocks that
+ have non-matching successor sets, and thus need to check their live_at_end
+ regsets for match in the first pass. */
+bool
+struct_equiv_init (int mode, struct equiv_info *info, bool check_regs_eq)
+{
+ if (!(mode & STRUCT_EQUIV_SUSPEND_UPDATES)
+ && ((info->x_block->flags & info->y_block->flags) & BB_DIRTY))
+ update_life_info_in_dirty_blocks (UPDATE_LIFE_GLOBAL_RM_NOTES,
+ (PROP_DEATH_NOTES
+ | ((mode & CLEANUP_POST_REGSTACK)
+ ? PROP_POST_REGSTACK : 0)));
+ info->mode = mode;
+ if (check_regs_eq && (mode & STRUCT_EQUIV_START))
+ {
+ if (!struct_equiv_regs_eq_p (info))
return false;
}
- info->mode = mode;
+ else if (mode & (STRUCT_EQUIV_FINAL | STRUCT_EQUIV_SUSPEND_UPDATES))
+ gcc_assert (struct_equiv_regs_eq_p (info));
if (mode & STRUCT_EQUIV_START)
{
info->x_input = info->y_input = info->input_reg = NULL_RTX;
@@ -1036,7 +1057,10 @@ struct_equiv_init (int mode, struct equi
info->common_live = ALLOC_REG_SET (®_obstack);
info->x_local_live = ALLOC_REG_SET (®_obstack);
info->y_local_live = ALLOC_REG_SET (®_obstack);
- COPY_REG_SET (info->common_live, info->x_block->il.rtl->global_live_at_end);
+ COPY_REG_SET (info->common_live,
+ ((info->x_block->flags & BB_DIRTY
+ ? info->y_block : info->x_block)
+ ->il.rtl->global_live_at_end));
struct_equiv_make_checkpoint (&info->best_match, info);
return true;
}
@@ -1100,8 +1124,7 @@ struct_equiv_block_eq (int mode, struct
x_stop = info->cur.x_start;
y_stop = info->cur.y_start;
}
- if (!struct_equiv_init (mode, info))
- gcc_unreachable ();
+ struct_equiv_init (mode, info, false);
/* Skip simple jumps at the end of the blocks. Complex jumps still
need to be compared for equivalence, which we'll do below. */
