On Wed, May 24, 2023 at 2:03 AM Richard Biener via Gcc-patches
<gcc-patches@gcc.gnu.org> wrote:
>
> On Wed, May 24, 2023 at 1:16 AM Andrew Pinski via Gcc-patches
> <gcc-patches@gcc.gnu.org> wrote:
> >
> > While trying to understand how to use the ! operand for match
> > patterns, I noticed that the debug dumps would print out applying
> > a pattern but nothing when it was rejected in the end. This was confusing
> > me.
> > This adds that by emitting a dump for the failed case.
> > Note the patch is little more complex as we don't want to print out
> > if debug counter rejected the pattern and then we need to fix up
> > when we mark needing a label or not.
> >
> > OK? Bootstrapped and tested on x86_64-linux-gnu with no regressions.
>
> Hmm, can we maybe simply move the
>
> if (UNLIKELY
> (debug_dump)) fprintf (dump_file, "Applying pattern %s:%d, %s:%d\n",
> "match.pd", 1157, __FILE__, __LINE__);
>
> right before the return true; instead?
Yes that should work. Let me do a patch for that.
Thanks,
Andrew
>
> > gcc/ChangeLog:
> >
> > * genmatch.cc (needs_label): New variable
> > (expr::gen_transform): Set needs_label
> > if we use the local_label.
> > (dt_simplify::gen_1): Use `_1` for the debug count label.
> > After the local label, emit debug print for the failure.
> > Emit `_1` label if needed.
> > ---
> > gcc/genmatch.cc | 28 ++++++++++++++++++++++++----
> > 1 file changed, 24 insertions(+), 4 deletions(-)
> >
> > diff --git a/gcc/genmatch.cc b/gcc/genmatch.cc
> > index 177c13d87cb..2ea80d341a2 100644
> > --- a/gcc/genmatch.cc
> > +++ b/gcc/genmatch.cc
> > @@ -2433,6 +2433,7 @@ capture_info::walk_c_expr (c_expr *e)
> > /* The current label failing the current matched pattern during
> > code generation. */
> > static char *fail_label;
> > +static bool needs_label;
> >
> > /* Code generation off the decision tree and the refered AST nodes. */
> >
> > @@ -2611,6 +2612,7 @@ expr::gen_transform (FILE *f, int indent, const char
> > *dest, bool gimple,
> > fprintf_indent (f, indent,
> > "if (!_r%d) goto %s;\n",
> > depth, fail_label);
> > + needs_label = true;
> > if (*opr == CONVERT_EXPR)
> > {
> > indent -= 4;
> > @@ -2640,11 +2642,13 @@ expr::gen_transform (FILE *f, int indent, const
> > char *dest, bool gimple,
> > {
> > fprintf_indent (f, indent, "if (!_r%d)\n", depth);
> > fprintf_indent (f, indent, " goto %s;\n", fail_label);
> > + needs_label = true;
> > }
> > if (force_leaf)
> > {
> > fprintf_indent (f, indent, "if (EXPR_P (_r%d))\n", depth);
> > fprintf_indent (f, indent, " goto %s;\n", fail_label);
> > + needs_label = true;
> > }
> > if (*opr == CONVERT_EXPR)
> > {
> > @@ -3409,7 +3413,8 @@ 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;
> > + needs_label = false;
> > + bool needs_label_1 = false;
> >
> > /* Analyze captures and perform early-outs on the incoming arguments
> > that cover cases we cannot handle. */
> > @@ -3484,8 +3489,8 @@ 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);
> > - needs_label = true;
> > + fprintf_indent (f, indent, "if (UNLIKELY (!dbg_cnt (match))) goto
> > %s_1;\n", fail_label);
> > + needs_label_1 = true;
> > }
> >
> > fprintf_indent (f, indent, "if (UNLIKELY (debug_dump)) "
> > @@ -3718,7 +3723,22 @@ dt_simplify::gen_1 (FILE *f, int indent, bool
> > gimple, operand *result)
> > indent -= 2;
> > fprintf_indent (f, indent, "}\n");
> > if (needs_label)
> > - fprintf (f, "%s:;\n", fail_label);
> > + {
> > + fprintf (f, "%s:;\n", fail_label);
> > + if (s->kind == simplify::SIMPLIFY)
> > + {
> > + fprintf_indent (f, indent, "if (UNLIKELY (debug_dump)) "
> > + "fprintf (dump_file, \"Pattern failed ");
> > + fprintf (f, "%%s:%%d, %%s:%%d\\n\", ");
> > + output_line_directive (f,
> > + result ? result->location :
> > s->match->location, true,
> > + true);
> > + fprintf (f, ", __FILE__, __LINE__);\n");
> > + }
> > + }
> > + if (needs_label_1)
> > + fprintf (f, "%s_1:;\n", fail_label);
> > + needs_label = false;
> > fail_label = NULL;
> > }
> >
> > --
> > 2.31.1
> >
