Support branch statements `break`/`continue`/`fallthrough`

src/tilde_proc.cpp

@@ -68,7 +68,7 @@ gb_internal cgProcedure *cg_procedure_create(cgModule *m, Entity *entity, bool i
 	p->children.allocator      = a;
 	// p->defer_stmts.allocator   = a;
 	// p->blocks.allocator        = a;
-	// p->branch_blocks.allocator = a;
+	p->branch_blocks.allocator = a;
 	p->context_stack.allocator = a;
 	p->scope_stack.allocator   = a;
 	map_init(&p->variable_map);
@@ -128,7 +128,7 @@ gb_internal cgProcedure *cg_procedure_create_dummy(cgModule *m, String const &li
 	p->children.allocator      = a;
 	// p->defer_stmts.allocator   = a;
 	// p->blocks.allocator        = a;
-	// p->branch_blocks.allocator = a;
+	p->branch_blocks.allocator = a;
 	p->scope_stack.allocator = a;
 	p->context_stack.allocator = a;
 	map_init(&p->variable_map);
@@ -165,6 +165,16 @@ gb_internal void cg_procedure_begin(cgProcedure *p) {
 		return;
 	}
 
+
+	DeclInfo *decl = decl_info_of_entity(p->entity);
+	if (decl != nullptr) {
+		for_array(i, decl->labels) {
+			BlockLabel bl = decl->labels[i];
+			cgBranchBlocks bb = {bl.label, nullptr, nullptr};
+			array_add(&p->branch_blocks, bb);
+		}
+	}
+
 	GB_ASSERT(p->type->kind == Type_Proc);
 	TypeProc *pt = &p->type->Proc;
 	if (pt->params == nullptr) {

src/tilde_stmt.cpp

@@ -1330,14 +1330,10 @@ gb_internal void cg_build_stmt(cgProcedure *p, Ast *node) {
 				}
 			}
 		}
-		if (block != nullptr) {
-			cg_emit_defer_stmts(p, cgDeferExit_Branch, block);
-		}
-
+		GB_ASSERT(block != nullptr);
 
+		cg_emit_defer_stmts(p, cgDeferExit_Branch, block);
 		tb_inst_goto(p->func, block);
-		tb_inst_set_control(p->func, block);
-		tb_inst_unreachable(p->func);
 
 		tb_inst_set_control(p->func, prev_block);
 	case_end;