The following patch fixes
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88282
The patch was successfully bootstrapped and tested on
x86/x86-64/ppc64/aarch64.
Committed as rev. 266784.
Index: ChangeLog
===================================================================
--- ChangeLog (revision 266783)
+++ ChangeLog (working copy)
@@ -1,3 +1,9 @@
+2018-12-04 Vladimir Makarov <vmaka...@redhat.com>
+
+ PR target/88282
+ * ira-costs.c (exec): Try bigger class to use smaller register
+ move cost.
+
2018-12-04 Michael Ploujnikov <michael.ploujni...@oracle.com>
PR ipa/88297
Index: ira-costs.c
===================================================================
--- ira-costs.c (revision 266678)
+++ ira-costs.c (working copy)
@@ -1314,28 +1314,50 @@ record_operand_costs (rtx_insn *insn, en
machine_mode mode = GET_MODE (SET_SRC (set));
cost_classes_t cost_classes_ptr = regno_cost_classes[regno];
enum reg_class *cost_classes = cost_classes_ptr->classes;
- reg_class_t rclass, hard_reg_class, pref_class;
+ reg_class_t rclass, hard_reg_class, pref_class, bigger_hard_reg_class;
int cost, k;
+ move_table *move_costs;
bool dead_p = find_regno_note (insn, REG_DEAD, REGNO (src));
ira_init_register_move_cost_if_necessary (mode);
+ move_costs = ira_register_move_cost[mode];
hard_reg_class = REGNO_REG_CLASS (other_regno);
+ bigger_hard_reg_class = ira_pressure_class_translate[hard_reg_class];
+ if (bigger_hard_reg_class == NO_REGS
+ && (other_regno == STACK_POINTER_REGNUM
+#ifdef STATIC_CHAIN_REGNUM
+ || other_regno == STATIC_CHAIN_REGNUM
+#endif
+ || other_regno == FRAME_POINTER_REGNUM
+ || other_regno == HARD_FRAME_POINTER_REGNUM))
+ bigger_hard_reg_class = GENERAL_REGS;
/* Target code may return any cost for mode which does not
fit the the hard reg class (e.g. DImode for AREG on
i386). Check this and use a bigger class to get the
right cost. */
if (! ira_hard_reg_in_set_p (other_regno, mode,
reg_class_contents[hard_reg_class]))
- hard_reg_class = ira_pressure_class_translate[hard_reg_class];
+ hard_reg_class = bigger_hard_reg_class;
i = regno == (int) REGNO (src) ? 1 : 0;
for (k = cost_classes_ptr->num - 1; k >= 0; k--)
{
rclass = cost_classes[k];
- cost = ((i == 0
- ? ira_register_move_cost[mode][hard_reg_class][rclass]
- : ira_register_move_cost[mode][rclass][hard_reg_class])
- * frequency);
- op_costs[i]->cost[k] = cost;
+ cost = (i == 0
+ ? move_costs[hard_reg_class][rclass]
+ : move_costs[rclass][hard_reg_class]);
+ /* Target code might define wrong big costs for smaller
+ reg classes or reg classes containing only fixed hard
+ regs. Try a bigger class. */
+ if (bigger_hard_reg_class != hard_reg_class)
+ {
+ int cost2 = (i == 0
+ ? move_costs[bigger_hard_reg_class][rclass]
+ : move_costs[rclass][bigger_hard_reg_class]);
+ if (cost2 < cost)
+ cost = cost2;
+ }
+
+ op_costs[i]->cost[k] = cost * frequency;
/* If we have assigned a class to this allocno in our
first pass, add a cost to this alternative
corresponding to what we would add if this allocno
@@ -1350,7 +1372,7 @@ record_operand_costs (rtx_insn *insn, en
else if (ira_reg_class_intersect[pref_class][rclass]
== NO_REGS)
op_costs[i]->cost[k]
- += (ira_register_move_cost[mode][pref_class][rclass]
+ += (move_costs[pref_class][rclass]
* frequency);
}
/* If this insn is a single set copying operand 1 to
