On Tue, Apr 18, 2023 at 12:21 PM Tamar Christina via Gcc-patches
<[email protected]> wrote:
>
> Hi All,
>
> This is a small QoL codegen improvement for match.pd to not emit labels when
> they are not needed. The codegen is nice and there is a small (but
> consistent)
> improvement in compile time.
>
> Bootstrapped Regtested on aarch64-none-linux-gnu and no issues.
>
> Ok for master?
OK. Btw - how many labels does this remove? (just wc -l the generated files?)
Richard.
> Thanks,
> Tamar
>
> gcc/ChangeLog:
>
> PR bootstrap/84402
> * genmatch.cc (dt_simplify::gen_1): Only emit labels if used.
>
> --- inline copy of patch --
> diff --git a/gcc/genmatch.cc b/gcc/genmatch.cc
> index
> 4fab4135347c43d95546a7df0bb1c4d074937288..638606b2502f640e59527fc5a0b23fa3bedd0cee
> 100644
> --- a/gcc/genmatch.cc
> +++ b/gcc/genmatch.cc
> @@ -3352,6 +3352,7 @@ dt_simplify::gen_1 (FILE *f, int indent, bool gimple,
> operand *result)
> char local_fail_label[256];
> snprintf (local_fail_label, 256, "next_after_fail%u", ++fail_label_cnt);
> fail_label = local_fail_label;
> + bool needs_label = false;
>
> /* Analyze captures and perform early-outs on the incoming arguments
> that cover cases we cannot handle. */
> @@ -3366,6 +3367,7 @@ dt_simplify::gen_1 (FILE *f, int indent, bool gimple,
> operand *result)
> fprintf_indent (f, indent,
> "if (TREE_SIDE_EFFECTS (_p%d)) goto %s;\n",
> i, fail_label);
> + needs_label = true;
> if (verbose >= 1)
> warning_at (as_a <expr *> (s->match)->ops[i]->location,
> "forcing toplevel operand to have no "
> @@ -3381,6 +3383,7 @@ dt_simplify::gen_1 (FILE *f, int indent, bool gimple,
> operand *result)
> fprintf_indent (f, indent,
> "if (TREE_SIDE_EFFECTS (captures[%d])) "
> "goto %s;\n", i, fail_label);
> + needs_label = true;
> if (verbose >= 1)
> warning_at (cinfo.info[i].c->location,
> "forcing captured operand to have no "
> @@ -3423,7 +3426,10 @@ dt_simplify::gen_1 (FILE *f, int indent, bool gimple,
> operand *result)
> }
>
> if (s->kind == simplify::SIMPLIFY)
> - fprintf_indent (f, indent, "if (UNLIKELY (!dbg_cnt (match))) goto
> %s;\n", fail_label);
> + {
> + fprintf_indent (f, indent, "if (UNLIKELY (!dbg_cnt (match))) goto
> %s;\n", fail_label);
> + needs_label = true;
> + }
>
> fprintf_indent (f, indent, "if (UNLIKELY (dump_file && (dump_flags &
> TDF_FOLDING))) "
> "fprintf (dump_file, \"%s ",
> @@ -3496,9 +3502,12 @@ dt_simplify::gen_1 (FILE *f, int indent, bool gimple,
> operand *result)
> "res_op->resimplify (%s, valueize);\n",
> !e->force_leaf ? "lseq" : "NULL");
> if (e->force_leaf)
> - fprintf_indent (f, indent,
> - "if (!maybe_push_res_to_seq (res_op, NULL)) "
> - "goto %s;\n", fail_label);
> + {
> + fprintf_indent (f, indent,
> + "if (!maybe_push_res_to_seq (res_op, NULL))
> "
> + "goto %s;\n", fail_label);
> + needs_label = true;
> + }
> }
> }
> else if (result->type == operand::OP_CAPTURE
> @@ -3554,9 +3563,12 @@ dt_simplify::gen_1 (FILE *f, int indent, bool gimple,
> operand *result)
> continue;
> if (cinfo.info[i].result_use_count
> > cinfo.info[i].match_use_count)
> - fprintf_indent (f, indent,
> - "if (! tree_invariant_p (captures[%d])) "
> - "goto %s;\n", i, fail_label);
> + {
> + fprintf_indent (f, indent,
> + "if (! tree_invariant_p (captures[%d])) "
> + "goto %s;\n", i, fail_label);
> + needs_label = true;
> + }
> }
> for (unsigned j = 0; j < e->ops.length (); ++j)
> {
> @@ -3607,6 +3619,7 @@ dt_simplify::gen_1 (FILE *f, int indent, bool gimple,
> operand *result)
> {
> fprintf_indent (f, indent, "if (!_r)\n");
> fprintf_indent (f, indent, " goto %s;\n", fail_label);
> + needs_label = true;
> }
> }
> }
> @@ -3647,7 +3660,8 @@ dt_simplify::gen_1 (FILE *f, int indent, bool gimple,
> operand *result)
> }
> indent -= 2;
> fprintf_indent (f, indent, "}\n");
> - fprintf (f, "%s:;\n", fail_label);
> + if (needs_label)
> + fprintf (f, "%s:;\n", fail_label);
> fail_label = NULL;
> }
>
>
>
>
>
> --
