[PATCH] [Stage1] Refactor tree-ssa-operands.c

[Richard Biener]

On Wed, Apr 22, 2020 at 8:40 PM Giuliano Belinassi
<giuliano.belinassi@usp.br> wrote:
>
> This patch refactors tree-ssa-operands.c by wrapping the global
> variables into a class, and also removes unused code.
>
> Just sending this for when Stage1 is back again.
>
> I ran the testsuite and bootstraped in a x86_64 linux machine and
> found no issues.

First of all thanks for doing this.  I have a few editorial suggestions
about the class setup - first the name build_virtual_operands is
badly chosen, I prefer operand_scanner.  Second I suggest to
have the CTOR take the invariants as arguments which is the
stmt we operate on and its containing function.  Thus,

  operand_scanner (function *, gimple *);

which makes passing those down functions unnecessary.

Since build_vuses is now a member and allocated for each stmt
which would be a regression I'd suggest to use an auto_vec
with some pre-allocated storage, thus change it to

  auto_vec<tree *, 16> build_uses;

that also makes the destructor trivial (please simply remove
cleanup_build_arrays).  I guess there's further possibilities
for streamlining the initialization/teardown process but that's
better done as followup.

Otherwise the change looks OK to me.

Thanks,
Richard.

> gcc/ChangeLog:
> 2020-04-22  Giuliano Belinassi  <giuliano.belinassi@usp.br>
>
>         * tree-ssa-operands.c (build_virtual_operands): New class.
>         (operands_bitmap_obstack): Remove.
>         (n_initialized): Remove.
>         (build_uses): Move to build_virtual_operands class.
>         (build_vuse): Same as above.
>         (build_vdef): Same as above.
>         (verify_ssa_operands): Same as above.
>         (finalize_ssa_uses): Same as above.
>         (cleanup_build_arrays): Same as above.
>         (finalize_ssa_stmt_operands): Same as above.
>         (start_ssa_stmt_operands): Same as above.
>         (append_use): Same as above.
>         (append_vdef): Same as above.
>         (add_virtual_operand): Same as above.
>         (add_stmt_operand): Same as above.
>         (get_mem_ref_operands): Same as above.
>         (get_tmr_operands): Same as above.
>         (maybe_add_call_vops): Same as above.
>         (get_asm_stmt_operands): Same as above.
>         (get_expr_operands): Same as above.
>         (parse_ssa_operands): Same as above.
>         (finalize_ssa_defs): Same as above.
>         (build_ssa_operands): Same as above, plus create a C-like wrapper.
>         (update_stmt_operands): Create an instance of build_virtual_operands.