`@(default_calling_convention = ...)` for `foreign` blocks

6 files changed, 143 insertions, 25 deletions

diff --git a/src/check_decl.cpp b/src/check_decl.cpp
index 1361ac31c..bc8d35a40 100644
--- a/src/check_decl.cpp
+++ b/src/check_decl.cpp
@@ -467,6 +467,10 @@ void check_proc_decl(Checker *c, Entity *e, DeclInfo *d) {
 
 
 	if (d != nullptr && d->attributes.count > 0) {
+		StringSet set = {};
+		string_set_init(&set, heap_allocator());
+		defer (string_set_destroy(&set));
+
 		for_array(i, d->attributes) {
 			AstNode *attr = d->attributes[i];
 			if (attr->kind != AstNode_Attribute) continue;
@@ -500,14 +504,17 @@ void check_proc_decl(Checker *c, Entity *e, DeclInfo *d) {
 					}
 				}
 
+				if (string_set_exists(&set, name)) {
+					error(elem, "Previous declaration of `%.*s`", LIT(name));
+				} else {
+					string_set_add(&set, name);
+				}
+
 				if (name == "link_name") {
-					if (link_name.len > 0) {
-						error(elem, "Previous declaration of `link_name`");
-					}
 					if (ev.kind == ExactValue_String) {
 						link_name = ev.value_string;
 					} else {
-						error(elem, "Expected a string value for `link_name`");
+						error(elem, "Expected a string value for `%.*s`", LIT(name));
 					}
 				} else {
 					error(elem, "Unknown attribute element name `%.*s`", LIT(name));
diff --git a/src/check_stmt.cpp b/src/check_stmt.cpp
index 7cbf479e4..3add868ec 100644
--- a/src/check_stmt.cpp
+++ b/src/check_stmt.cpp
@@ -1670,8 +1670,11 @@ void check_stmt_internal(Checker *c, AstNode *node, u32 flags) {
 		CheckerContext prev_context = c->context;
 		if (ok) {
 			c->context.curr_foreign_library = foreign_library;
+			c->context.default_foreign_cc = ProcCC_C;
 		}
 
+		check_foreign_block_decl_attributes(c, fb);
+
 		for_array(i, fb->decls) {
 			AstNode *decl = fb->decls[i];
 			if (decl->kind == AstNode_ValueDecl && decl->ValueDecl.is_mutable) {
diff --git a/src/check_type.cpp b/src/check_type.cpp
index 95b876ef8..5d3382f47 100644
--- a/src/check_type.cpp
+++ b/src/check_type.cpp
@@ -1888,6 +1888,15 @@ bool check_procedure_type(Checker *c, Type *type, AstNode *proc_type_node, Array
 		}
 	}
 
+	ProcCallingConvention cc = pt->calling_convention;
+	if (cc == ProcCC_ForeignBlockDefault) {
+		cc = ProcCC_C;
+		if (c->context.default_foreign_cc > 0) {
+			cc = c->context.default_foreign_cc;
+		}
+	}
+	GB_ASSERT(cc > 0);
+
 	type->Proc.node                 = proc_type_node;
 	type->Proc.scope                = c->context.scope;
 	type->Proc.params               = params;
@@ -1895,18 +1904,18 @@ bool check_procedure_type(Checker *c, Type *type, AstNode *proc_type_node, Array
 	type->Proc.results              = results;
 	type->Proc.result_count         = cast(i32)result_count;
 	type->Proc.variadic             = variadic;
-	type->Proc.calling_convention   = pt->calling_convention;
+	type->Proc.calling_convention   = cc;
 	type->Proc.is_polymorphic       = pt->generic;
 	type->Proc.specialization_count = specialization_count;
 
 	if (param_count > 0) {
 		Entity *end = params->Tuple.variables[param_count-1];
 		if (end->flags&EntityFlag_CVarArg) {
-			if (pt->calling_convention == ProcCC_Odin) {
+			if (cc == ProcCC_Odin) {
 				error(end->token, "Odin calling convention does not support #c_vararg");
-			} else if (pt->calling_convention == ProcCC_Contextless) {
+			} else if (cc == ProcCC_Contextless) {
 				error(end->token, "Odin's contextless calling convention does not support #c_vararg");
-			} else if (pt->calling_convention == ProcCC_Fast) {
+			} else if (cc == ProcCC_Fast) {
 				error(end->token, "Fast calling convention does not support #c_vararg");
 			} else {
 				type->Proc.c_vararg = true;
diff --git a/src/checker.cpp b/src/checker.cpp
index 35744585a..180c99a73 100644
--- a/src/checker.cpp
+++ b/src/checker.cpp
@@ -423,6 +423,7 @@ struct CheckerContext {
 	Type *     type_hint;
 	DeclInfo * curr_proc_decl;
 	AstNode *  curr_foreign_library;
+	ProcCallingConvention default_foreign_cc;
 
 	bool       in_foreign_export;
 	bool       collect_delayed_decls;
@@ -1854,6 +1855,7 @@ void check_procedure_overloading(Checker *c, Entity *e) {
 	gb_temp_arena_memory_end(tmp);
 }
 
+void check_foreign_block_decl_attributes(Checker *c, AstNodeForeignBlockDecl *fb);
 
 #include "check_expr.cpp"
 #include "check_type.cpp"
@@ -1861,6 +1863,71 @@ void check_procedure_overloading(Checker *c, Entity *e) {
 #include "check_stmt.cpp"
 
 
+void check_foreign_block_decl_attributes(Checker *c, AstNodeForeignBlockDecl *fb) {
+	if (fb->attributes.count == 0) return;
+	StringSet set = {};
+	string_set_init(&set, heap_allocator());
+	defer (string_set_destroy(&set));
+
+	for_array(i, fb->attributes) {
+		AstNode *attr = fb->attributes[i];
+		if (attr->kind != AstNode_Attribute) continue;
+		for_array(j, attr->Attribute.elems) {
+			AstNode *elem = attr->Attribute.elems[j];
+			String name = {};
+			AstNode *value = nullptr;
+
+			switch (elem->kind) {
+			case_ast_node(i, Ident, elem);
+				name = i->token.string;
+			case_end;
+			case_ast_node(fv, FieldValue, elem);
+				GB_ASSERT(fv->field->kind == AstNode_Ident);
+				name = fv->field->Ident.token.string;
+				value = fv->value;
+			case_end;
+			default:
+				error(elem, "Invalid attribute element");
+				continue;
+			}
+
+			ExactValue ev = {};
+			if (value != nullptr) {
+				Operand op = {};
+				check_expr(c, &op, value);
+				if (op.mode != Addressing_Constant) {
+					error(value, "An attribute element must be constant");
+				} else {
+					ev = op.value;
+				}
+			}
+
+			if (string_set_exists(&set, name)) {
+				error(elem, "Previous declaration of `%.*s`", LIT(name));
+				continue;
+			} else {
+				string_set_add(&set, name);
+			}
+
+			if (name == "default_calling_convention") {
+				if (ev.kind == ExactValue_String) {
+					auto cc = string_to_calling_convention(ev.value_string);
+					if (cc == ProcCC_Invalid) {
+						error(elem, "Unknown procedure calling convention: `%.*s`\n", LIT(ev.value_string));
+					} else {
+						c->context.default_foreign_cc = cc;
+					}
+				} else {
+					error(elem, "Expected a string value for `%.*s`", LIT(name));
+				}
+			} else {
+				error(elem, "Unknown attribute element name `%.*s`", LIT(name));
+			}
+		}
+	}
+}
+
+
 
 bool check_arity_match(Checker *c, AstNodeValueDecl *vd, bool is_global) {
 	isize lhs = vd->names.count;
@@ -1990,6 +2057,7 @@ void check_collect_value_decl(Checker *c, AstNode *decl) {
 				GB_ASSERT(fl->kind == AstNode_Ident);
 				e->Variable.is_foreign = true;
 				e->Variable.foreign_library_ident = fl;
+
 			} else if (c->context.in_foreign_export) {
 				e->Variable.is_export = true;
 			}
@@ -2054,6 +2122,18 @@ void check_collect_value_decl(Checker *c, AstNode *decl) {
 					GB_ASSERT(fl->kind == AstNode_Ident);
 					e->Procedure.foreign_library_ident = fl;
 					e->Procedure.is_foreign = true;
+
+					GB_ASSERT(pl->type->kind == AstNode_ProcType);
+					auto cc = pl->type->ProcType.calling_convention;
+					if (cc == ProcCC_ForeignBlockDefault) {
+						cc = ProcCC_C;
+						if (c->context.default_foreign_cc > 0) {
+							cc = c->context.default_foreign_cc;
+						}
+					}
+					GB_ASSERT(cc != ProcCC_Invalid);
+					pl->type->ProcType.calling_convention = cc;
+
 				} else if (c->context.in_foreign_export) {
 					e->Procedure.is_export = true;
 				}
@@ -2103,6 +2183,8 @@ void check_add_foreign_block_decl(Checker *c, AstNode *decl) {
 		c->context.curr_foreign_library = nullptr;
 	}
 
+	check_foreign_block_decl_attributes(c, fb);
+
 	c->context.collect_delayed_decls = true;
 	check_collect_entities(c, fb->decls);
 	c->context = prev_context;
diff --git a/src/common.cpp b/src/common.cpp
index 1379db50d..22e94ed84 100644
--- a/src/common.cpp
+++ b/src/common.cpp
@@ -114,6 +114,7 @@ u128 fnv128a(void const *data, isize len) {
 
 #include "map.cpp"
 #include "ptr_set.cpp"
+#include "string_set.cpp"
 #include "priority_queue.cpp"
 
 
diff --git a/src/parser.cpp b/src/parser.cpp
index caeb3f95c..fef9a95a0 100644
--- a/src/parser.cpp
+++ b/src/parser.cpp
@@ -110,6 +110,8 @@ enum ProcCallingConvention {
 	ProcCC_C           = 3,
 	ProcCC_Std         = 4,
 	ProcCC_Fast        = 5,
+
+	ProcCC_ForeignBlockDefault = -1,
 };
 
 enum VarDeclFlag {
@@ -332,6 +334,7 @@ AST_NODE_KIND(_DeclBegin,      "", i32) \
 		AstNode *        foreign_library; \
 		Token            open, close;     \
 		Array<AstNode *> decls;           \
+		Array<AstNode *> attributes;      \
 		bool             been_handled;    \
 		CommentGroup     docs;            \
 	}) \
@@ -842,6 +845,7 @@ AstNode *clone_ast_node(gbAllocator a, AstNode *node) {
 	case AstNode_ForeignBlockDecl:
 		n->ForeignBlockDecl.foreign_library = clone_ast_node(a, n->ForeignBlockDecl.foreign_library);
 		n->ForeignBlockDecl.decls           = clone_ast_node_array(a, n->ForeignBlockDecl.decls);
+		n->ForeignBlockDecl.attributes      = clone_ast_node_array(a, n->ForeignBlockDecl.attributes);
 		break;
 	case AstNode_Label:
 		n->Label.name = clone_ast_node(a, n->Label.name);
@@ -1548,6 +1552,8 @@ AstNode *ast_foreign_block_decl(AstFile *f, Token token, AstNode *foreign_librar
 	result->ForeignBlockDecl.close           = close;
 	result->ForeignBlockDecl.decls           = decls;
 	result->ForeignBlockDecl.docs            = docs;
+
+	result->ForeignBlockDecl.attributes.allocator = heap_allocator();
 	return result;
 }
 
@@ -3247,6 +3253,22 @@ AstNode *parse_results(AstFile *f) {
 	return list;
 }
 
+
+ProcCallingConvention string_to_calling_convention(String s) {
+	if (s == "odin") {
+		return ProcCC_Odin;
+	} else if (s == "contextless") {
+		return ProcCC_Contextless;
+	} else if (s == "cdecl" || s == "c") {
+		return ProcCC_C;
+	} else if (s == "stdcall" || s == "std") {
+		return ProcCC_Std;
+	} else if (s == "fastcall" || s == "fast") {
+		return ProcCC_Fast;
+	}
+	return ProcCC_Invalid;
+}
+
 AstNode *parse_proc_type(AstFile *f, Token proc_token) {
 	AstNode *params = nullptr;
 	AstNode *results = nullptr;
@@ -3254,24 +3276,16 @@ AstNode *parse_proc_type(AstFile *f, Token proc_token) {
 	ProcCallingConvention cc = ProcCC_Invalid;
 	if (f->curr_token.kind == Token_String) {
 		Token token = expect_token(f, Token_String);
-		String conv = token.string;
-		if (conv == "odin") {
-			cc = ProcCC_Odin;
-		} else if (conv == "contextless") {
-			cc = ProcCC_Contextless;
-		} else if (conv == "cdecl" || conv == "c") {
-			cc = ProcCC_C;
-		} else if (conv == "stdcall" || conv == "std") {
-			cc = ProcCC_Std;
-		} else if (conv == "fastcall" || conv == "fast") {
-			cc = ProcCC_Fast;
+		auto c = string_to_calling_convention(token.string);
+		if (c == ProcCC_Invalid) {
+			syntax_error(token, "Unknown procedure calling convention: `%.*s`\n", LIT(token.string));
 		} else {
-			syntax_error(token, "Unknown procedure tag #%.*s\n", LIT(conv));
+			cc = c;
 		}
 	}
 	if (cc == ProcCC_Invalid) {
 		if (f->in_foreign_block) {
-			cc = ProcCC_C;
+			cc = ProcCC_ForeignBlockDefault;
 		} else {
 			cc = ProcCC_Odin;
 		}
@@ -4578,7 +4592,6 @@ AstNode *parse_stmt(AstFile *f) {
 		f->expr_level++;
 		if (f->curr_token.kind != Token_CloseParen) {
 			elems = make_ast_node_array(f);
-
 			while (f->curr_token.kind != Token_CloseParen &&
 			       f->curr_token.kind != Token_EOF) {
 				AstNode *elem = parse_ident(f);
@@ -4601,12 +4614,15 @@ AstNode *parse_stmt(AstFile *f) {
 		AstNode *attribute = ast_attribute(f, token, open, close, elems);
 
 		AstNode *decl = parse_stmt(f);
-		if (decl->kind != AstNode_ValueDecl) {
-			syntax_error(decl, "Expected a value declaration after an attribute, got %.*s", LIT(ast_node_strings[decl->kind]));
+		if (decl->kind == AstNode_ValueDecl) {
+			array_add(&decl->ValueDecl.attributes, attribute);
+		} else if (decl->kind == AstNode_ForeignBlockDecl) {
+			array_add(&decl->ForeignBlockDecl.attributes, attribute);
+		} else {
+			syntax_error(decl, "Expected a value or foreign declaration after an attribute, got %.*s", LIT(ast_node_strings[decl->kind]));
 			return ast_bad_stmt(f, token, f->curr_token);
 		}
 
-		array_add(&decl->ValueDecl.attributes, attribute);
 		return decl;
 	}