match.pd: don't emit label if not needed

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.

gcc/ChangeLog:

	PR bootstrap/84402
	* genmatch.cc (dt_simplify::gen_1): Only emit labels if used.

diff --git a/gcc/genmatch.cc b/gcc/genmatch.cc
index 4fab4135347c43d95546a7df0bb1c4d074937288..638606b2502f640e59527fc5a0b23fa3bedd0cee 100644 (file)
--- 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;
 }