On Tue, Oct 25, 2022 at 11:27 PM Takayuki 'January June' Suwa
<jjsuwa_sys3...@yahoo.co.jp> wrote:
>
> On 2022/10/26 5:09, Jan-Benedict Glaw wrote:
> > I didn't yet actually check the warning, it may be bogus.
>
> This "problem" can occur in the following two places calling
> xtensa_split_DI_reg_imm():
>
> - (define_expand "movdi") @ line 943-945
> - (define_split) @ line 989
>
> and the former causes the "real" problem:
>
> [from gcc/insn-emit.cc (generated by building)]
>
> > /* ../../gcc/config/xtensa/xtensa.md:932 */
> > rtx
> > gen_movdi (rtx operand0,
> > rtx operand1)
> > {
> > rtx_insn *_val = 0;
> > start_sequence ();
> > {
> > rtx operands[2]; // only 2 elements
> > operands[0] = operand0;
> > operands[1] = operand1;
> > #define FAIL return (end_sequence (), _val)
> > #define DONE return (_val = get_insns (), end_sequence (), _val)
> > #line 936 "../../gcc/config/xtensa/xtensa.md"
> > {
> > if (CONSTANT_P (operands[1]))
> > {
> > /* Split in halves if 64-bit Const-to-Reg moves
> > because of offering further optimization opportunities. */
> > if (register_operand (operands[0], DImode))
> > {
> > xtensa_split_DI_reg_imm (operands); // out-of-bounds!
> > emit_move_insn (operands[0], operands[1]);
> > emit_move_insn (operands[2], operands[3]); // out-of-bounds!
> > DONE;
> > }
>
> The latter is not a problem as the array is large enough (up to
> MAX_RECOG_OPERANDS-1).
>
> ===
>
> gcc/ChangeLog:
>
> * config/xtensa/xtensa.md (movdi):
> Copy operands[0...1] to ops[0...3] and then use the latter before
> calling xtensa_split_DI_reg_imm() and emitting insns.
> ---
> gcc/config/xtensa/xtensa.md | 7 ++++---
> 1 file changed, 4 insertions(+), 3 deletions(-)
Committed to master as obvious after cleaning up
the commit message.
--
Thanks.
-- Max
