c++: replace tf_norm with a local flag

Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK
for trunk?

-- >8 --

The tf_norm flag controlling whether to build diagnostic information
during constraint normalization doesn't need to be a global tsubst flag,
and is confusingly named.  This patch replaces it with a boolean flag
local to normalization.

gcc/cp/ChangeLog:

	* constraint.cc (norm_info::norm_info): Take a boolean parameter
	instead of tsubst_flags_t.
	(norm_info::generate_diagnostics): Turn this predicate function
	into a data member.
	(normalize_logical_operation): Adjust after norm_info changes.
	(normalize_concept_check): Likewise.
	(normalize_atom): Likewise.
	(get_normalized_constraints_from_info): Likewise.
	(normalize_concept_definition): Likewise.
	(normalize_constraint_expression): Likewise.
	(normalize_placeholder_type_constraints): Likewise.
	(satisfy_nondeclaration_constraints): Likewise.
	* cp-tree.h (enum tsubst_flags): Remove tf_norm.
---
 gcc/cp/constraint.cc | 40 ++++++++++++++++++++--------------------
 gcc/cp/cp-tree.h     |  3 +--
 2 files changed, 21 insertions(+), 22 deletions(-)

On 5/3/24 11:26, Patrick Palka wrote:
> Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK
> for trunk?

OK.

> -- >8 --
> 
> The tf_norm flag controlling whether to build diagnostic information
> during constraint normalization doesn't need to be a global tsubst flag,
> and is confusingly named.  This patch replaces it with a boolean flag
> local to normalization.
> 
> gcc/cp/ChangeLog:
> 
> 	* constraint.cc (norm_info::norm_info): Take a boolean parameter
> 	instead of tsubst_flags_t.
> 	(norm_info::generate_diagnostics): Turn this predicate function
> 	into a data member.
> 	(normalize_logical_operation): Adjust after norm_info changes.
> 	(normalize_concept_check): Likewise.
> 	(normalize_atom): Likewise.
> 	(get_normalized_constraints_from_info): Likewise.
> 	(normalize_concept_definition): Likewise.
> 	(normalize_constraint_expression): Likewise.
> 	(normalize_placeholder_type_constraints): Likewise.
> 	(satisfy_nondeclaration_constraints): Likewise.
> 	* cp-tree.h (enum tsubst_flags): Remove tf_norm.
> ---
>   gcc/cp/constraint.cc | 40 ++++++++++++++++++++--------------------
>   gcc/cp/cp-tree.h     |  3 +--
>   2 files changed, 21 insertions(+), 22 deletions(-)
> 
> diff --git a/gcc/cp/constraint.cc b/gcc/cp/constraint.cc
> index 8a3b5d80ba7..3f0dab79bcd 100644
> --- a/gcc/cp/constraint.cc
> +++ b/gcc/cp/constraint.cc
> @@ -622,33 +622,29 @@ parameter_mapping_equivalent_p (tree t1, tree t2)
>   
>   struct norm_info : subst_info
>   {
> -  explicit norm_info (tsubst_flags_t cmp)
> -    : norm_info (NULL_TREE, cmp)
> +  explicit norm_info (bool diag)
> +    : norm_info (NULL_TREE, diag)
>     {}
>   
>     /* Construct a top-level context for DECL.  */
>   
> -  norm_info (tree in_decl, tsubst_flags_t complain)
> -    : subst_info (tf_warning_or_error | complain, in_decl)
> +  norm_info (tree in_decl, bool diag)
> +    : subst_info (tf_warning_or_error, in_decl),
> +      generate_diagnostics (diag)
>     {
>       if (in_decl)
>         {
>   	initial_parms = DECL_TEMPLATE_PARMS (in_decl);
> -	if (generate_diagnostics ())
> +	if (generate_diagnostics)
>   	  context = build_tree_list (NULL_TREE, in_decl);
>         }
>       else
>         initial_parms = current_template_parms;
>     }
>   
> -  bool generate_diagnostics() const
> -  {
> -    return complain & tf_norm;
> -  }
> -
>     void update_context(tree expr, tree args)
>     {
> -    if (generate_diagnostics ())
> +    if (generate_diagnostics)
>         {
>   	tree map = build_parameter_mapping (expr, args, ctx_parms ());
>   	context = tree_cons (map, expr, context);
> @@ -679,6 +675,10 @@ struct norm_info : subst_info
>        template parameters of ORIG_DECL.  */
>   
>     tree initial_parms = NULL_TREE;
> +
> +  /* Whether to build diagnostic information during normalization.  */
> +
> +  bool generate_diagnostics;
>   };
>   
>   static tree normalize_expression (tree, tree, norm_info);
> @@ -693,7 +693,7 @@ normalize_logical_operation (tree t, tree args, tree_code c, norm_info info)
>     tree t1 = normalize_expression (TREE_OPERAND (t, 1), args, info);
>   
>     /* Build a new info object for the constraint.  */
> -  tree ci = info.generate_diagnostics()
> +  tree ci = info.generate_diagnostics
>       ? build_tree_list (t, info.context)
>       : NULL_TREE;
>   
> @@ -777,7 +777,7 @@ normalize_concept_check (tree check, tree args, norm_info info)
>     if (!norm_cache)
>       norm_cache = hash_table<norm_hasher>::create_ggc (31);
>     norm_entry *entry = nullptr;
> -  if (!info.generate_diagnostics ())
> +  if (!info.generate_diagnostics)
>       {
>         /* Cache the normal form of the substituted concept-id (when not
>   	 diagnosing).  */
> @@ -831,7 +831,7 @@ normalize_atom (tree t, tree args, norm_info info)
>     if (info.in_decl && concept_definition_p (info.in_decl))
>       ATOMIC_CONSTR_EXPR_FROM_CONCEPT_P (atom) = true;
>   
> -  if (!info.generate_diagnostics ())
> +  if (!info.generate_diagnostics)
>       {
>         /* Cache the ATOMIC_CONSTRs that we return, so that sat_hasher::equal
>   	 later can cheaply compare two atoms using just pointer equality.  */
> @@ -910,7 +910,7 @@ get_normalized_constraints_from_info (tree ci, tree in_decl, bool diag = false)
>   
>     /* Substitution errors during normalization are fatal.  */
>     ++processing_template_decl;
> -  norm_info info (in_decl, diag ? tf_norm : tf_none);
> +  norm_info info (in_decl, diag);
>     tree t = get_normalized_constraints (CI_ASSOCIATED_CONSTRAINTS (ci), info);
>     --processing_template_decl;
>   
> @@ -1012,7 +1012,7 @@ normalize_concept_definition (tree tmpl, bool diag)
>     gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
>     tree def = get_concept_definition (DECL_TEMPLATE_RESULT (tmpl));
>     ++processing_template_decl;
> -  norm_info info (tmpl, diag ? tf_norm : tf_none);
> +  norm_info info (tmpl, diag);
>     tree norm = get_normalized_constraints (def, info);
>     --processing_template_decl;
>   
> @@ -1035,7 +1035,7 @@ normalize_constraint_expression (tree expr, norm_info info)
>     if (!expr || expr == error_mark_node)
>       return expr;
>   
> -  if (!info.generate_diagnostics ())
> +  if (!info.generate_diagnostics)
>       if (tree *p = hash_map_safe_get (normalized_map, expr))
>         return *p;
>   
> @@ -1043,7 +1043,7 @@ normalize_constraint_expression (tree expr, norm_info info)
>     tree norm = get_normalized_constraints (expr, info);
>     --processing_template_decl;
>   
> -  if (!info.generate_diagnostics ())
> +  if (!info.generate_diagnostics)
>       hash_map_safe_put<hm_ggc> (normalized_map, expr, norm);
>   
>     return norm;
> @@ -3190,7 +3190,7 @@ normalize_placeholder_type_constraints (tree t, bool diag)
>   			   ? TMPL_PARMS_DEPTH (initial_parms) + 1 : 1),
>   		 make_tree_vec (0), initial_parms);
>   
> -  norm_info info (diag ? tf_norm : tf_none);
> +  norm_info info (diag);
>     info.initial_parms = initial_parms;
>     return normalize_constraint_expression (constr, info);
>   }
> @@ -3226,7 +3226,7 @@ satisfy_nondeclaration_constraints (tree t, tree args, sat_info info)
>       }
>     else if (TREE_CODE (t) == NESTED_REQ)
>       {
> -      norm_info ninfo (info.noisy () ? tf_norm : tf_none);
> +      norm_info ninfo (info.noisy ());
>         /* The TREE_TYPE contains the set of template parameters that were in
>   	 scope for this nested requirement; use them as the initial template
>   	 parameters for normalization.  */
> diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h
> index bc8e22cc39f..d4e216e361e 100644
> --- a/gcc/cp/cp-tree.h
> +++ b/gcc/cp/cp-tree.h
> @@ -5696,8 +5696,7 @@ enum tsubst_flags {
>   				declaration.  */
>     tf_no_cleanup = 1 << 10,   /* Do not build a cleanup
>   				(build_target_expr and friends) */
> -  tf_norm = 1 << 11,		 /* Build diagnostic information during
> -				    constraint normalization.  */
> +  /* 1 << 11 is free to use.  */
>     tf_tst_ok = 1 << 12,		 /* Allow a typename-specifier to name
>   				    a template (C++17 or later).  */
>     tf_dguide = 1 << 13,		/* Building a deduction guide from a ctor.  */