gccrs: Unify raw attribute values

Attribute values were used as raw string, this is error prone and
makes renaming harder. Using a constexpr instead will leverage the power
of the compiler and emit an error when an incorrect builtin attribute
value is used.

gcc/rust/ChangeLog:

	* ast/rust-ast.cc (Attribute::check_cfg_predicate): Change raw
	string to constexpr call.
	(Attribute::separate_cfg_attrs): Likewise.
	* backend/rust-compile-base.cc (should_mangle_item): Likewise.
	(HIRCompileBase::setup_fndecl): Likewise.
	(HIRCompileBase::handle_cold_attribute_on_fndecl): Likewise.
	* checks/errors/privacy/rust-privacy-reporter.cc (find_proc_macro_attribute):
	Likewise.
	* checks/errors/rust-unsafe-checker.cc (check_target_attr):
	Likewise.
	* expand/rust-cfg-strip.cc (fails_cfg): Likewise.
	(fails_cfg_with_expand): Likewise.
	(expand_cfg_attrs): Likewise.
	* expand/rust-macro-builtins.cc: Likewise.
	* hir/rust-ast-lower-base.cc (ASTLoweringBase::handle_outer_attributes): Likewise.
	(ASTLoweringBase::lower_macro_definition): Likewise.
	* hir/rust-hir-dump.cc (Dump::visit): Likewise.
	* parse/rust-parse-impl.h (Parser::parse_doc_comment): Likewise.
	* parse/rust-parse.cc (extract_module_path): Likewise.
	* resolve/rust-early-name-resolver.cc (is_macro_use_module):
	Likewise.
	(EarlyNameResolver::visit): Likewise.
	* resolve/rust-toplevel-name-resolver-2.0.cc (is_macro_export):
	Likwise.
	* rust-session-manager.cc (Session::injection): Likewise.
	* typecheck/rust-hir-type-check-base.cc (TypeCheckBase::parse_repr_options): Likewise.
	* util/rust-attributes.cc (is_proc_macro_type): Likewise.
	(AttributeChecker::check_attribute): Likewise.
	(AttributeChecker::visit): Likewise.
	* util/rust-hir-map.cc (Mappings::insert_macro_def): Likewise.
	* util/rust-attribute-values.h: New file.

Signed-off-by: Pierre-Emmanuel Patry <pierre-emmanuel.patry@embecosm.com>

2 files changed, 6 insertions, 4 deletions

diff --git a/gcc/rust/hir/rust-ast-lower-base.cc b/gcc/rust/hir/rust-ast-lower-base.cc
index da36d75..cec2410 100644
--- a/gcc/rust/hir/rust-ast-lower-base.cc
+++ b/gcc/rust/hir/rust-ast-lower-base.cc
@@ -20,6 +20,7 @@
 #include "rust-ast-lower-type.h"
 #include "rust-ast-lower-pattern.h"
 #include "rust-ast-lower-extern.h"
+#include "rust-attribute-values.h"
 
 namespace Rust {
 namespace HIR {
@@ -722,12 +723,12 @@ ASTLoweringBase::handle_outer_attributes (const ItemWrapper &item)
 	  continue;
 	}
 
-      bool is_lang_item = str_path.compare ("lang") == 0
+      bool is_lang_item = str_path == Values::Attributes::LANG
 			  && attr.has_attr_input ()
 			  && attr.get_attr_input ().get_attr_input_type ()
 			       == AST::AttrInput::AttrInputType::LITERAL;
 
-      bool is_doc_item = str_path.compare ("doc") == 0;
+      bool is_doc_item = str_path == Values::Attributes::DOC;
 
       if (is_doc_item)
 	handle_doc_item_attribute (item, attr);
@@ -967,7 +968,7 @@ ASTLoweringBase::lower_macro_definition (AST::MacroRulesDefinition &def)
 {
   auto is_export = false;
   for (const auto &attr : def.get_outer_attrs ())
-    if (attr.get_path ().as_string () == "macro_export")
+    if (attr.get_path ().as_string () == Values::Attributes::MACRO_EXPORT)
       is_export = true;
 
   if (is_export)
diff --git a/gcc/rust/hir/rust-hir-dump.cc b/gcc/rust/hir/rust-hir-dump.cc
index 8870ece..8078ed1 100644
--- a/gcc/rust/hir/rust-hir-dump.cc
+++ b/gcc/rust/hir/rust-hir-dump.cc
@@ -23,6 +23,7 @@
 #include "rust-hir-type.h"
 #include "rust-hir.h"
 #include <string>
+#include "rust-attribute-values.h"
 
 namespace Rust {
 namespace HIR {
@@ -633,7 +634,7 @@ void
 Dump::visit (AST::Attribute &attribute)
 {
   // Special, no begin/end as this is called by do_inner_attrs.
-  put_field ("path", attribute.get_path ().as_string ());
+  put_field (Values::Attributes::PATH, attribute.get_path ().as_string ());
 
   std::string str = "none";
   if (attribute.has_attr_input ())