The following patch fixes
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88157
The patch was successfully bootstrapped on x86 and x86-64 with GO and D.
Committed as rev. 266422.
Index: ChangeLog
===================================================================
--- ChangeLog (revision 266421)
+++ ChangeLog (working copy)
@@ -1,3 +1,9 @@
+2018-11-23 Vladimir Makarov <vmaka...@redhat.com>
+
+ PR bootstrap/88157
+ * ira-costs.c (record_operand_costs): Use bigger hard reg class if
+ its mode does not fit to the original class.
+
2018-11-23 Martin Sebor <mse...@redhat.com>
PR tree-optimization/87756
Index: ira-costs.c
===================================================================
--- ira-costs.c (revision 266385)
+++ ira-costs.c (working copy)
@@ -1319,6 +1319,13 @@ record_operand_costs (rtx_insn *insn, en
bool dead_p = find_regno_note (insn, REG_DEAD, REGNO (src));
hard_reg_class = REGNO_REG_CLASS (other_regno);
+ /* 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];
i = regno == (int) REGNO (src) ? 1 : 0;
for (k = cost_classes_ptr->num - 1; k >= 0; k--)
{
