[Bug rtl-optimization/87720] [9 Regression] [MIPS] ICE: gcc.c-torture/execute/builtins/lib/chk.c:33:1: in int_mode_for_mode, at stor-layout.c:403 after r265398

[paul.hua.gm at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87720

--- Comment #2 from Paul Hua <paul.hua.gm at gmail dot com> ---
untested patch:

Index: gcc/combine.c
===================================================================
--- gcc/combine.c       (revision 265456)
+++ gcc/combine.c       (working copy)
@@ -14965,7 +14965,11 @@
          if (TEST_HARD_REG_BIT (fixed_reg_set, REGNO (src)))
            continue;

-         rtx new_reg = gen_reg_rtx (GET_MODE (dest));
+         rtx new_reg;
+         if (GET_CODE(dest) == PC)
+           new_reg = gen_reg_rtx (GET_MODE (src));
+         else
+           new_reg = gen_reg_rtx (GET_MODE (dest));
          rtx_insn *insn1 = gen_move_insn (new_reg, src);
          rtx_insn *insn2 = gen_move_insn (dest, new_reg);
          emit_insn_after (insn1, insn);
Index: gcc/expr.c
===================================================================
--- gcc/expr.c  (revision 265456)
+++ gcc/expr.c  (working copy)
@@ -3684,7 +3684,12 @@
 rtx_insn *
 emit_move_insn_1 (rtx x, rtx y)
 {
-  machine_mode mode = GET_MODE (x);
+  machine_mode mode;
+  if (GET_CODE (x) == PC)
+    mode = GET_MODE (y);
+  else /* Include  (GET_CODE (y) = PC) */
+    mode = GET_MODE (x);
+
   enum insn_code code;

   gcc_assert ((unsigned int) mode < (unsigned int) MAX_MACHINE_MODE);