stage1: memory/report overhaul

- split util_base.hpp from util.hpp
- new namespaces: `mem` and `heap`
- new `mem::Allocator` interface
- new `heap::CAllocator` impl with global `heap::c_allocator`
- new `heap::ArenaAllocator` impl
- new `mem::TypeInfo` extracts names without RTTI
- name extraction is enabled w/ ZIG_ENABLE_MEM_PROFILE=1
- new `mem::List` takes explicit `Allocator&` parameter
- new `mem::HashMap` takes explicit `Allocator&` parameter
- add Codegen.pass1_arena and use for all `ZigValue` allocs
- deinit Codegen.pass1_arena early in `zig_llvm_emit_output()`

src/mem.cpp

@@ -0,0 +1,37 @@
+/*
+ * Copyright (c) 2020 Andrew Kelley
+ *
+ * This file is part of zig, which is MIT licensed.
+ * See http://opensource.org/licenses/MIT
+ */
+
+#include "config.h"
+#include "mem.hpp"
+#include "mem_profile.hpp"
+#include "heap.hpp"
+
+namespace mem {
+
+void init() {
+    heap::bootstrap_allocator_state.init("heap::bootstrap_allocator");
+    heap::c_allocator_state.init("heap::c_allocator");
+}
+
+void deinit() {
+    heap::c_allocator_state.deinit();
+    heap::bootstrap_allocator_state.deinit();
+}
+
+#ifdef ZIG_ENABLE_MEM_PROFILE
+void print_report(FILE *file) {
+    heap::c_allocator_state.print_report(file);
+    intern_counters.print_report(file);
+}
+#endif
+
+#ifdef ZIG_ENABLE_MEM_PROFILE
+bool report_print = false;
+FILE *report_file{nullptr};
+#endif
+
+} // namespace mem