https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109035
--- Comment #6 from chenglulu <chenglulu at loongson dot cn> ---
I tried changing the code,
diff --git a/gcc/lra-eliminations.cc b/gcc/lra-eliminations.cc
index 42206366669..efaea6922b5 100644
--- a/gcc/lra-eliminations.cc
+++ b/gcc/lra-eliminations.cc
@@ -914,6 +914,11 @@ eliminate_regs_in_insn (rtx_insn *insn, bool replace_p,
bool first_p,
/* First see if the source is of the form (plus (...) CST). */
if (plus_src && poly_int_rtx_p (XEXP (plus_src, 1), &offset))
plus_cst_src = plus_src;
+ else if (plus_src && ira_reg_equiv[REGNO (XEXP (plus_src, 1))].constant)
+ {
+ poly_int_rtx_p (ira_reg_equiv[REGNO (XEXP (plus_src, 1))].constant,
&offset);
+ plus_cst_src = gen_rtx_PLUS (GET_MODE (XEXP (plus_src, 0)),XEXP
(plus_src, 0), ira_reg_equiv[REGNO (XEXP (plus_src, 1))].constant);
+ }
/* Check that the first operand of the PLUS is a hard reg or
the lowpart subreg of one. */
if (plus_cst_src)
Redundant instructions can be eliminated, but I don't know if it can be
modified like this.
