/* IRA processing allocno lives to build allocno live ranges.
- Copyright (C) 2006-2019 Free Software Foundation, Inc.
+ Copyright (C) 2006-2020 Free Software Foundation, Inc.
Contributed by Vladimir Makarov <vmakarov@redhat.com>.
This file is part of GCC.
/* Check and make if necessary conflicts for definition DEF of class
DEF_CL of the current insn with input operands. Process only
- constraints of alternative ALT. */
+ constraints of alternative ALT.
+
+ One of three things is true when this function is called:
+
+ (1) DEF is an earlyclobber for alternative ALT. Input operands then
+ conflict with DEF in ALT unless they explicitly match DEF via 0-9
+ constraints.
+
+ (2) DEF matches (via 0-9 constraints) an operand that is an
+ earlyclobber for alternative ALT. Other input operands then
+ conflict with DEF in ALT.
+
+ (3) [FOR_TIE_P] Some input operand X matches DEF for alternative ALT.
+ Input operands with a different value from X then conflict with
+ DEF in ALT.
+
+ However, there's still a judgement call to make when deciding
+ whether a conflict in ALT is important enough to be reflected
+ in the pan-alternative allocno conflict set. */
static void
-check_and_make_def_conflict (int alt, int def, enum reg_class def_cl)
+check_and_make_def_conflict (int alt, int def, enum reg_class def_cl,
+ bool for_tie_p)
{
int use, use_match;
ira_allocno_t a;
if (use == def || recog_data.operand_type[use] == OP_OUT)
continue;
+ /* An earlyclobber on DEF doesn't apply to an input operand X if X
+ explicitly matches DEF, but it applies to other input operands
+ even if they happen to be the same value as X.
+
+ In contrast, if an input operand X is tied to a non-earlyclobber
+ DEF, there's no conflict with other input operands that have the
+ same value as X. */
+ if (op_alt[use].matches == def
+ || (for_tie_p
+ && rtx_equal_p (recog_data.operand[use],
+ recog_data.operand[op_alt[def].matched])))
+ continue;
+
if (op_alt[use].anything_ok)
use_cl = ALL_REGS;
else
use_cl = op_alt[use].cl;
+ if (use_cl == NO_REGS)
+ continue;
+
+ /* If DEF is simply a tied operand, ignore cases in which this
+ alternative requires USE to have a likely-spilled class.
+ Adding a conflict would just constrain USE further if DEF
+ happens to be allocated first. */
+ if (for_tie_p && targetm.class_likely_spilled_p (use_cl))
+ continue;
/* If there's any alternative that allows USE to match DEF, do not
record a conflict. If that causes us to create an invalid
- instruction due to the earlyclobber, reload must fix it up. */
+ instruction due to the earlyclobber, reload must fix it up.
+
+ Likewise, if we're treating a tied DEF like a partial earlyclobber,
+ do not record a conflict if there's another alternative in which
+ DEF is neither tied nor earlyclobber. */
for (alt1 = 0; alt1 < recog_data.n_alternatives; alt1++)
{
if (!TEST_BIT (preferred_alternatives, alt1))
&& recog_data.constraints[use - 1][0] == '%'
&& op_alt1[use - 1].matches == def))
break;
+ if (for_tie_p
+ && !op_alt1[def].earlyclobber
+ && op_alt1[def].matched < 0
+ && alternative_class (op_alt1, def) != NO_REGS
+ && alternative_class (op_alt1, use) != NO_REGS)
+ break;
}
if (alt1 < recog_data.n_alternatives)
if ((use_match = op_alt[use].matches) >= 0)
{
- if (use_match == def)
- continue;
+ gcc_checking_assert (use_match != def);
if (op_alt[use_match].anything_ok)
use_cl = ALL_REGS;
/* Make conflicts of early clobber pseudo registers of the current
insn with its inputs. Avoid introducing unnecessary conflicts by
checking classes of the constraints and pseudos because otherwise
- significant code degradation is possible for some targets. */
+ significant code degradation is possible for some targets.
+
+ For these purposes, tying an input to an output makes that output act
+ like an earlyclobber for inputs with a different value, since the output
+ register then has a predetermined purpose on input to the instruction. */
static void
make_early_clobber_and_input_conflicts (void)
{
if (TEST_BIT (preferred_alternatives, alt))
for (def = 0; def < n_operands; def++)
{
- def_cl = NO_REGS;
- if (op_alt[def].earlyclobber)
+ if (op_alt[def].anything_ok)
+ def_cl = ALL_REGS;
+ else
+ def_cl = op_alt[def].cl;
+ if (def_cl != NO_REGS)
{
- if (op_alt[def].anything_ok)
- def_cl = ALL_REGS;
- else
- def_cl = op_alt[def].cl;
- check_and_make_def_conflict (alt, def, def_cl);
+ if (op_alt[def].earlyclobber)
+ check_and_make_def_conflict (alt, def, def_cl, false);
+ else if (op_alt[def].matched >= 0
+ && !targetm.class_likely_spilled_p (def_cl))
+ check_and_make_def_conflict (alt, def, def_cl, true);
}
+
if ((def_match = op_alt[def].matches) >= 0
&& (op_alt[def_match].earlyclobber
|| op_alt[def].earlyclobber))
def_cl = ALL_REGS;
else
def_cl = op_alt[def_match].cl;
- check_and_make_def_conflict (alt, def, def_cl);
+ check_and_make_def_conflict (alt, def, def_cl, false);
}
}
}
return SET_SRC (set);
}
+#ifdef EH_RETURN_DATA_REGNO
+
+/* Add EH return hard registers as conflict hard registers to allocnos
+ living at end of BB. For most allocnos it is already done in
+ process_bb_node_lives when we processing input edges but it does
+ not work when and EH edge is edge out of the current region. This
+ function covers such out of region edges. */
+static void
+process_out_of_region_eh_regs (basic_block bb)
+{
+ edge e;
+ edge_iterator ei;
+ unsigned int i;
+ bitmap_iterator bi;
+ bool eh_p = false;
+
+ FOR_EACH_EDGE (e, ei, bb->succs)
+ if ((e->flags & EDGE_EH)
+ && IRA_BB_NODE (e->dest)->parent != IRA_BB_NODE (bb)->parent)
+ eh_p = true;
+
+ if (! eh_p)
+ return;
+
+ EXECUTE_IF_SET_IN_BITMAP (df_get_live_out (bb), FIRST_PSEUDO_REGISTER, i, bi)
+ {
+ ira_allocno_t a = ira_curr_regno_allocno_map[i];
+ for (int n = ALLOCNO_NUM_OBJECTS (a) - 1; n >= 0; n--)
+ {
+ ira_object_t obj = ALLOCNO_OBJECT (a, n);
+ for (int k = 0; ; k++)
+ {
+ unsigned int regno = EH_RETURN_DATA_REGNO (k);
+ if (regno == INVALID_REGNUM)
+ break;
+ SET_HARD_REG_BIT (OBJECT_CONFLICT_HARD_REGS (obj), regno);
+ SET_HARD_REG_BIT (OBJECT_TOTAL_CONFLICT_HARD_REGS (obj), regno);
+ }
+ }
+ }
+}
+
+#endif
+
/* Process insns of the basic block given by its LOOP_TREE_NODE to
update allocno live ranges, allocno hard register conflicts,
intersected calls, and register pressure info for allocnos for the
EXECUTE_IF_SET_IN_BITMAP (reg_live_out, FIRST_PSEUDO_REGISTER, j, bi)
mark_pseudo_regno_live (j);
+#ifdef EH_RETURN_DATA_REGNO
+ process_out_of_region_eh_regs (bb);
+#endif
+
freq = REG_FREQ_FROM_BB (bb);
if (freq == 0)
freq = 1;
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