Adding some shape to toolchain semantic analysis (#1092)

toolchain/semantics/semantics_ir.cpp

@@ -0,0 +1,28 @@
+// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
+// Exceptions. See /LICENSE for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+#include "toolchain/semantics/semantics_ir.h"
+
+#include "common/check.h"
+#include "llvm/Support/FormatVariadic.h"
+#include "toolchain/lexer/tokenized_buffer.h"
+
+namespace Carbon {
+
+void SemanticsIR::Block::Add(llvm::StringRef name, Node named_entity) {
+  ordering_.push_back(named_entity);
+  name_lookup_.insert({name, named_entity});
+}
+
+auto SemanticsIR::AddFunction(Block& block, ParseTree::Node decl_node,
+                              ParseTree::Node name_node)
+    -> Semantics::Function& {
+  int32_t index = functions_.size();
+  functions_.push_back(Semantics::Function(decl_node, name_node));
+  block.Add(parse_tree_->GetNodeText(name_node),
+            Node(Node::Kind::Function, index));
+  return functions_[index];
+}
+
+}  // namespace Carbon