* basic-block.h (fixup_abnormal_edges): Adjust prototype.
* reload1.c (reload): Adjust call to fixup_abnormal_edges. Rediscover
basic blocks and call commit_edge_insertions directly.
(fixup_abnormal_edges): Move from here to...
* cfgrtl.c (fixup_abnormal_edges): ...here. Only insert instructions
on the edges and return whether some have actually been inserted.
* reg-stack.c (convert_regs): Fix up abnormal edges before inserting
compensation code.
From-SVN: r171556
+2011-03-26 Eric Botcazou <ebotcazou@adacore.com>
+
+ * basic-block.h (fixup_abnormal_edges): Adjust prototype.
+ * reload1.c (reload): Adjust call to fixup_abnormal_edges. Rediscover
+ basic blocks and call commit_edge_insertions directly.
+ (fixup_abnormal_edges): Move from here to...
+ * cfgrtl.c (fixup_abnormal_edges): ...here. Only insert instructions
+ on the edges and return whether some have actually been inserted.
+ * reg-stack.c (convert_regs): Fix up abnormal edges before inserting
+ compensation code.
+
2011-03-26 Andrey Belevantsev <abel@ispras.ru>
PR rtl-optimization/48144
extern rtx block_label (basic_block);
extern bool purge_all_dead_edges (void);
extern bool purge_dead_edges (basic_block);
+extern bool fixup_abnormal_edges (void);
/* In cfgbuild.c. */
extern void find_many_sub_basic_blocks (sbitmap);
extern bool mark_dfs_back_edges (void);
extern void set_edge_can_fallthru_flag (void);
extern void update_br_prob_note (basic_block);
-extern void fixup_abnormal_edges (void);
extern bool inside_basic_block_p (const_rtx);
extern bool control_flow_insn_p (const_rtx);
extern rtx get_last_bb_insn (basic_block);
insert_insn_on_edge, commit_edge_insertions
- CFG updating after insn simplification
purge_dead_edges, purge_all_dead_edges
+ - CFG fixing after coarse manipulation
+ fixup_abnormal_edges
Functions not supposed for generic use:
- Infrastructure to determine quickly basic block for insn
return purged;
}
+/* This is used by a few passes that emit some instructions after abnormal
+ calls, moving the basic block's end, while they in fact do want to emit
+ them on the fallthru edge. Look for abnormal call edges, find backward
+ the call in the block and insert the instructions on the edge instead.
+
+ Similarly, handle instructions throwing exceptions internally.
+
+ Return true when instructions have been found and inserted on edges. */
+
+bool
+fixup_abnormal_edges (void)
+{
+ bool inserted = false;
+ basic_block bb;
+
+ FOR_EACH_BB (bb)
+ {
+ edge e;
+ edge_iterator ei;
+
+ /* Look for cases we are interested in - calls or instructions causing
+ exceptions. */
+ FOR_EACH_EDGE (e, ei, bb->succs)
+ if ((e->flags & EDGE_ABNORMAL_CALL)
+ || ((e->flags & (EDGE_ABNORMAL | EDGE_EH))
+ == (EDGE_ABNORMAL | EDGE_EH)))
+ break;
+
+ if (e && !CALL_P (BB_END (bb)) && !can_throw_internal (BB_END (bb)))
+ {
+ rtx insn;
+
+ /* Get past the new insns generated. Allow notes, as the insns
+ may be already deleted. */
+ insn = BB_END (bb);
+ while ((NONJUMP_INSN_P (insn) || NOTE_P (insn))
+ && !can_throw_internal (insn)
+ && insn != BB_HEAD (bb))
+ insn = PREV_INSN (insn);
+
+ if (CALL_P (insn) || can_throw_internal (insn))
+ {
+ rtx stop, next;
+
+ e = find_fallthru_edge (bb->succs);
+
+ stop = NEXT_INSN (BB_END (bb));
+ BB_END (bb) = insn;
+
+ for (insn = NEXT_INSN (insn); insn != stop; insn = next)
+ {
+ next = NEXT_INSN (insn);
+ if (INSN_P (insn))
+ {
+ delete_insn (insn);
+
+ /* Sometimes there's still the return value USE.
+ If it's placed after a trapping call (i.e. that
+ call is the last insn anyway), we have no fallthru
+ edge. Simply delete this use and don't try to insert
+ on the non-existent edge. */
+ if (GET_CODE (PATTERN (insn)) != USE)
+ {
+ /* We're not deleting it, we're moving it. */
+ INSN_DELETED_P (insn) = 0;
+ PREV_INSN (insn) = NULL_RTX;
+ NEXT_INSN (insn) = NULL_RTX;
+
+ insert_insn_on_edge (insn, e);
+ inserted = true;
+ }
+ }
+ else if (!BARRIER_P (insn))
+ set_block_for_insn (insn, NULL);
+ }
+ }
+
+ /* It may be that we don't find any trapping insn. In this
+ case we discovered quite late that the insn that had been
+ marked as can_throw_internal in fact couldn't trap at all.
+ So we should in fact delete the EH edges out of the block. */
+ else
+ purge_dead_edges (bb);
+ }
+ }
+
+ return inserted;
+}
+
/* Same as split_block but update cfg_layout structures. */
static basic_block
cfg_altered |= convert_regs_2 (b);
}
+ /* We must fix up abnormal edges before inserting compensation code
+ because both mechanisms insert insns on edges. */
+ inserted |= fixup_abnormal_edges ();
+
inserted |= compensate_edges ();
clear_aux_for_blocks ();
- fixup_abnormal_edges ();
if (inserted)
commit_edge_insertions ();
rtx insn;
struct elim_table *ep;
basic_block bb;
+ bool inserted;
/* Make sure even insns with volatile mem refs are recognizable. */
init_recog ();
/* Free all the insn_chain structures at once. */
obstack_free (&reload_obstack, reload_startobj);
unused_insn_chains = 0;
- fixup_abnormal_edges ();
+
+ inserted = fixup_abnormal_edges ();
+
+ /* We've possibly turned single trapping insn into multiple ones. */
+ if (cfun->can_throw_non_call_exceptions)
+ {
+ sbitmap blocks;
+ blocks = sbitmap_alloc (last_basic_block);
+ sbitmap_ones (blocks);
+ find_many_sub_basic_blocks (blocks);
+ sbitmap_free (blocks);
+ }
+
+ if (inserted)
+ commit_edge_insertions ();
/* Replacing pseudos with their memory equivalents might have
created shared rtx. Subsequent passes would get confused
}
}
#endif
-
-/* This is used by reload pass, that does emit some instructions after
- abnormal calls moving basic block end, but in fact it wants to emit
- them on the edge. Looks for abnormal call edges, find backward the
- proper call and fix the damage.
-
- Similar handle instructions throwing exceptions internally. */
-void
-fixup_abnormal_edges (void)
-{
- bool inserted = false;
- basic_block bb;
-
- FOR_EACH_BB (bb)
- {
- edge e;
- edge_iterator ei;
-
- /* Look for cases we are interested in - calls or instructions causing
- exceptions. */
- FOR_EACH_EDGE (e, ei, bb->succs)
- {
- if (e->flags & EDGE_ABNORMAL_CALL)
- break;
- if ((e->flags & (EDGE_ABNORMAL | EDGE_EH))
- == (EDGE_ABNORMAL | EDGE_EH))
- break;
- }
- if (e && !CALL_P (BB_END (bb))
- && !can_throw_internal (BB_END (bb)))
- {
- rtx insn;
-
- /* Get past the new insns generated. Allow notes, as the insns
- may be already deleted. */
- insn = BB_END (bb);
- while ((NONJUMP_INSN_P (insn) || NOTE_P (insn))
- && !can_throw_internal (insn)
- && insn != BB_HEAD (bb))
- insn = PREV_INSN (insn);
-
- if (CALL_P (insn) || can_throw_internal (insn))
- {
- rtx stop, next;
-
- stop = NEXT_INSN (BB_END (bb));
- BB_END (bb) = insn;
- insn = NEXT_INSN (insn);
-
- e = find_fallthru_edge (bb->succs);
-
- while (insn && insn != stop)
- {
- next = NEXT_INSN (insn);
- if (INSN_P (insn))
- {
- delete_insn (insn);
-
- /* Sometimes there's still the return value USE.
- If it's placed after a trapping call (i.e. that
- call is the last insn anyway), we have no fallthru
- edge. Simply delete this use and don't try to insert
- on the non-existent edge. */
- if (GET_CODE (PATTERN (insn)) != USE)
- {
- /* We're not deleting it, we're moving it. */
- INSN_DELETED_P (insn) = 0;
- PREV_INSN (insn) = NULL_RTX;
- NEXT_INSN (insn) = NULL_RTX;
-
- insert_insn_on_edge (insn, e);
- inserted = true;
- }
- }
- else if (!BARRIER_P (insn))
- set_block_for_insn (insn, NULL);
- insn = next;
- }
- }
-
- /* It may be that we don't find any such trapping insn. In this
- case we discovered quite late that the insn that had been
- marked as can_throw_internal in fact couldn't trap at all.
- So we should in fact delete the EH edges out of the block. */
- else
- purge_dead_edges (bb);
- }
- }
-
- /* We've possibly turned single trapping insn into multiple ones. */
- if (cfun->can_throw_non_call_exceptions)
- {
- sbitmap blocks;
- blocks = sbitmap_alloc (last_basic_block);
- sbitmap_ones (blocks);
- find_many_sub_basic_blocks (blocks);
- sbitmap_free (blocks);
- }
-
- if (inserted)
- commit_edge_insertions ();
-
-#ifdef ENABLE_CHECKING
- /* Verify that we didn't turn one trapping insn into many, and that
- we found and corrected all of the problems wrt fixups on the
- fallthru edge. */
- verify_flow_info ();
-#endif
-}
projects / gcc.git / commitdiff