Keep track of the ABI in function types

We need to know the specified ABI in order to determine the linkage, it
might be a plain old rust function, an extern C function or a compiler
intrinsic and each of these needed to be handled differently.

6 files changed, 87 insertions, 34 deletions

diff --git a/gcc/rust/typecheck/rust-hir-type-check-implitem.h b/gcc/rust/typecheck/rust-hir-type-check-implitem.h
index 59ea4ef..b1eb2e3 100644
--- a/gcc/rust/typecheck/rust-hir-type-check-implitem.h
+++ b/gcc/rust/typecheck/rust-hir-type-check-implitem.h
@@ -33,9 +33,9 @@ class TypeCheckTopLevelExternItem : public TypeCheckBase
   using Rust::Resolver::TypeCheckBase::visit;
 
 public:
-  static void Resolve (HIR::ExternalItem *item)
+  static void Resolve (HIR::ExternalItem *item, const HIR::ExternBlock &parent)
   {
-    TypeCheckTopLevelExternItem resolver;
+    TypeCheckTopLevelExternItem resolver (parent);
     item->accept_vis (resolver);
   }
 
@@ -115,16 +115,21 @@ public:
     if (function.is_variadic ())
       flags |= FNTYPE_IS_VARADIC_FLAG;
 
-    auto fnType
-      = new TyTy::FnType (function.get_mappings ().get_hirid (),
-			  function.get_mappings ().get_defid (),
-			  function.get_item_name (), flags, std::move (params),
-			  ret_type, std::move (substitutions));
+    auto fnType = new TyTy::FnType (
+      function.get_mappings ().get_hirid (),
+      function.get_mappings ().get_defid (), function.get_item_name (), flags,
+      TyTy::FnType::get_abi_from_string (parent.get_abi (),
+					 parent.get_locus ()),
+      std::move (params), ret_type, std::move (substitutions));
     context->insert_type (function.get_mappings (), fnType);
   }
 
 private:
-  TypeCheckTopLevelExternItem () : TypeCheckBase () {}
+  TypeCheckTopLevelExternItem (const HIR::ExternBlock &parent)
+    : TypeCheckBase (), parent (parent)
+  {}
+
+  const HIR::ExternBlock &parent;
 };
 
 class TypeCheckTopLevelImplItem : public TypeCheckBase
@@ -233,11 +238,14 @@ public:
 	context->insert_type (param.get_mappings (), param_tyty);
       }
 
-    auto fnType = new TyTy::FnType (
-      function.get_mappings ().get_hirid (),
-      function.get_mappings ().get_defid (), function.get_function_name (),
-      function.is_method () ? FNTYPE_IS_METHOD_FLAG : FNTYPE_DEFAULT_FLAGS,
-      std::move (params), ret_type, std::move (substitutions));
+    auto fnType
+      = new TyTy::FnType (function.get_mappings ().get_hirid (),
+			  function.get_mappings ().get_defid (),
+			  function.get_function_name (),
+			  function.is_method () ? FNTYPE_IS_METHOD_FLAG
+						: FNTYPE_DEFAULT_FLAGS,
+			  TyTy::FnType::ABI::RUST, std::move (params), ret_type,
+			  std::move (substitutions));
     context->insert_type (function.get_mappings (), fnType);
   }
 
diff --git a/gcc/rust/typecheck/rust-hir-type-check-stmt.h b/gcc/rust/typecheck/rust-hir-type-check-stmt.h
index 77cbc06..54280e8 100644
--- a/gcc/rust/typecheck/rust-hir-type-check-stmt.h
+++ b/gcc/rust/typecheck/rust-hir-type-check-stmt.h
@@ -329,11 +329,12 @@ public:
 	context->insert_type (param.get_mappings (), param_tyty);
       }
 
-    auto fnType = new TyTy::FnType (function.get_mappings ().get_hirid (),
-				    function.get_mappings ().get_defid (),
-				    function.get_function_name (), false,
-				    std::move (params), ret_type,
-				    std::move (substitutions));
+    auto fnType
+      = new TyTy::FnType (function.get_mappings ().get_hirid (),
+			  function.get_mappings ().get_defid (),
+			  function.get_function_name (), FNTYPE_DEFAULT_FLAGS,
+			  TyTy::FnType::ABI::RUST, std::move (params), ret_type,
+			  std::move (substitutions));
     context->insert_type (function.get_mappings (), fnType);
 
     TyTy::FnType *resolved_fn_type = fnType;
diff --git a/gcc/rust/typecheck/rust-hir-type-check-toplevel.h b/gcc/rust/typecheck/rust-hir-type-check-toplevel.h
index 5bffe13..6ec17a9 100644
--- a/gcc/rust/typecheck/rust-hir-type-check-toplevel.h
+++ b/gcc/rust/typecheck/rust-hir-type-check-toplevel.h
@@ -287,11 +287,12 @@ public:
 	context->insert_type (param.get_mappings (), param_tyty);
       }
 
-    auto fnType = new TyTy::FnType (function.get_mappings ().get_hirid (),
-				    function.get_mappings ().get_defid (),
-				    function.get_function_name (),
-				    FNTYPE_DEFAULT_FLAGS, std::move (params),
-				    ret_type, std::move (substitutions));
+    auto fnType
+      = new TyTy::FnType (function.get_mappings ().get_hirid (),
+			  function.get_mappings ().get_defid (),
+			  function.get_function_name (), FNTYPE_DEFAULT_FLAGS,
+			  TyTy::FnType::ABI::RUST, std::move (params), ret_type,
+			  std::move (substitutions));
     context->insert_type (function.get_mappings (), fnType);
   }
 
@@ -337,7 +338,7 @@ public:
   {
     for (auto &item : extern_block.get_extern_items ())
       {
-	TypeCheckTopLevelExternItem::Resolve (item.get ());
+	TypeCheckTopLevelExternItem::Resolve (item.get (), extern_block);
       }
   }
 
diff --git a/gcc/rust/typecheck/rust-hir-type-check.cc b/gcc/rust/typecheck/rust-hir-type-check.cc
index 453f743..bee2748 100644
--- a/gcc/rust/typecheck/rust-hir-type-check.cc
+++ b/gcc/rust/typecheck/rust-hir-type-check.cc
@@ -546,11 +546,12 @@ TraitItemReference::get_type_from_fn (/*const*/ HIR::TraitItemFunc &fn) const
       context->insert_type (param.get_mappings (), param_tyty);
     }
 
-  auto resolved
-    = new TyTy::FnType (fn.get_mappings ().get_hirid (),
-			fn.get_mappings ().get_defid (),
-			function.get_function_name (), function.is_method (),
-			std::move (params), ret_type, substitutions);
+  auto resolved = new TyTy::FnType (
+    fn.get_mappings ().get_hirid (), fn.get_mappings ().get_defid (),
+    function.get_function_name (),
+    function.is_method () ? FNTYPE_IS_METHOD_FLAG : FNTYPE_DEFAULT_FLAGS,
+    TyTy::FnType::ABI::RUST, std::move (params), ret_type, substitutions);
+
   context->insert_type (fn.get_mappings (), resolved);
   return resolved;
 }
diff --git a/gcc/rust/typecheck/rust-tyty.cc b/gcc/rust/typecheck/rust-tyty.cc
index 7eb717f..316caea 100644
--- a/gcc/rust/typecheck/rust-tyty.cc
+++ b/gcc/rust/typecheck/rust-tyty.cc
@@ -882,7 +882,7 @@ FnType::clone () const
       std::pair<HIR::Pattern *, BaseType *> (p.first, p.second->clone ()));
 
   return new FnType (get_ref (), get_ty_ref (), get_id (), get_identifier (),
-		     flags, std::move (cloned_params),
+		     flags, abi, std::move (cloned_params),
 		     get_return_type ()->clone (), clone_substs (),
 		     get_combined_refs ());
 }
diff --git a/gcc/rust/typecheck/rust-tyty.h b/gcc/rust/typecheck/rust-tyty.h
index 0dfae37..7f149a9 100644
--- a/gcc/rust/typecheck/rust-tyty.h
+++ b/gcc/rust/typecheck/rust-tyty.h
@@ -1071,12 +1071,51 @@ private:
 class FnType : public BaseType, public SubstitutionRef
 {
 public:
+  // FIXME these could be constants
 #define FNTYPE_DEFAULT_FLAGS 0x00
 #define FNTYPE_IS_METHOD_FLAG 0x01
 #define FNTYPE_IS_EXTERN_FLAG 0x02
 #define FNTYPE_IS_VARADIC_FLAG 0X04
 
-  FnType (HirId ref, DefId id, std::string identifier, uint8_t flags,
+  enum ABI
+  {
+    UNKNOWN,
+    RUST,
+    INTRINSIC,
+    C,
+  };
+
+  static ABI get_abi_from_string (const std::string &abi, Location locus)
+  {
+    if (abi.compare ("rust") == 0)
+      return ABI::C;
+    else if (abi.compare ("rust-intrinsic") == 0)
+      return ABI::INTRINSIC;
+    else if (abi.compare ("C") == 0)
+      return ABI::C;
+
+    rust_error_at (locus, "unknown abi specified");
+    return ABI::UNKNOWN;
+  }
+
+  static std::string get_string_from_abi (ABI abi)
+  {
+    switch (abi)
+      {
+      case ABI::RUST:
+	return "rust";
+      case ABI::INTRINSIC:
+	return "rust-intrinsic";
+      case ABI::C:
+	return "C";
+
+      case ABI::UNKNOWN:
+	return "unknown";
+      }
+    return "unknown";
+  }
+
+  FnType (HirId ref, DefId id, std::string identifier, uint8_t flags, ABI abi,
 	  std::vector<std::pair<HIR::Pattern *, BaseType *>> params,
 	  BaseType *type, std::vector<SubstitutionParamMapping> subst_refs,
 	  std::set<HirId> refs = std::set<HirId> ())
@@ -1084,14 +1123,14 @@ public:
       SubstitutionRef (std::move (subst_refs),
 		       SubstitutionArgumentMappings::error ()),
       params (std::move (params)), type (type), flags (flags),
-      identifier (identifier), id (id)
+      identifier (identifier), id (id), abi (abi)
   {
     LocalDefId local_def_id = id & DEF_ID_LOCAL_DEF_MASK;
     rust_assert (local_def_id != UNKNOWN_LOCAL_DEFID);
   }
 
   FnType (HirId ref, HirId ty_ref, DefId id, std::string identifier,
-	  uint8_t flags,
+	  uint8_t flags, ABI abi,
 	  std::vector<std::pair<HIR::Pattern *, BaseType *>> params,
 	  BaseType *type, std::vector<SubstitutionParamMapping> subst_refs,
 	  std::set<HirId> refs = std::set<HirId> ())
@@ -1099,7 +1138,7 @@ public:
       SubstitutionRef (std::move (subst_refs),
 		       SubstitutionArgumentMappings::error ()),
       params (params), type (type), flags (flags), identifier (identifier),
-      id (id)
+      id (id), abi (abi)
   {
     LocalDefId local_def_id = id & DEF_ID_LOCAL_DEF_MASK;
     rust_assert (local_def_id != UNKNOWN_LOCAL_DEFID);
@@ -1184,12 +1223,15 @@ public:
   FnType *
   handle_substitions (SubstitutionArgumentMappings mappings) override final;
 
+  ABI get_abi () const { return abi; }
+
 private:
   std::vector<std::pair<HIR::Pattern *, BaseType *>> params;
   BaseType *type;
   uint8_t flags;
   std::string identifier;
   DefId id;
+  ABI abi;
 };
 
 class FnPtr : public BaseType