gccrs: resolve: Add extern crate proc macro collection

Create a mapping for procedural macros with their crate num.

gcc/rust/ChangeLog:

	* metadata/rust-extern-crate.h: Add proc macro getter.
	* rust-session-manager.cc (Session::load_extern_crate): Collect
	mappings and create mappings.
	* util/rust-hir-map.cc: Add insertion and lookup functions for
	every mapping.
	* util/rust-hir-map.h: Add function prototypes.

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

1 files changed, 26 insertions, 0 deletions

diff --git a/gcc/rust/rust-session-manager.cc b/gcc/rust/rust-session-manager.cc
index 572ecfa..ee7dd08 100644
--- a/gcc/rust/rust-session-manager.cc
+++ b/gcc/rust/rust-session-manager.cc
@@ -1024,6 +1024,32 @@ Session::load_extern_crate (const std::string &crate_name, location_t locus)
   Lexer lex (extern_crate.get_metadata ());
   Parser<Lexer> parser (lex);
   std::unique_ptr<AST::Crate> metadata_crate = parser.parse_crate ();
+
+  std::vector<ProcMacro::Attribute> attribute_macros;
+  std::vector<ProcMacro::CustomDerive> derive_macros;
+  std::vector<ProcMacro::Bang> bang_macros;
+  for (auto &macro : extern_crate.get_proc_macros ())
+    {
+      switch (macro.tag)
+	{
+	case ProcMacro::CUSTOM_DERIVE:
+	  derive_macros.push_back (macro.payload.custom_derive);
+	  break;
+	case ProcMacro::ATTR:
+	  attribute_macros.push_back (macro.payload.attribute);
+	  break;
+	case ProcMacro::BANG:
+	  bang_macros.push_back (macro.payload.bang);
+	  break;
+	default:
+	  gcc_unreachable ();
+	}
+    }
+
+  mappings->insert_attribute_proc_macros (crate_num, attribute_macros);
+  mappings->insert_derive_proc_macros (crate_num, derive_macros);
+  mappings->insert_bang_proc_macros (crate_num, bang_macros);
+
   AST::Crate &parsed_crate
     = mappings->insert_ast_crate (std::move (metadata_crate), crate_num);