delete tool/instruction.rb

Previous commit changed insns.def format. Now is the time for its
generators. In doing so I chose to modernize the system, not just
patch.  My attempt includes

- extensive use of Onigumo regular expressions
- split from one big file (instruction.rb) into separated MVC
- partial view

Also, let me take this opportunity to kill old unused features
such as

- stack caching
- minsns / yasmdata which are never seriously used
- yarvarch document generation (moved to doc/)
- vast majority of unused arguments to insns2vm.rb

This commit generates VM source codes that cleanly compile, and
the generated binary passes tests.  At least for me.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@61733 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

tool/ruby_vm/models/c_expr.rb

@@ -0,0 +1,41 @@
+#! /your/favourite/path/to/ruby
+# -*- mode: ruby; coding: utf-8; indent-tabs-mode: nil; ruby-indent-level: 2 -*-
+# -*- frozen_string_literal: true; -*-
+# -*- warn_indent: true; -*-
+#
+# Copyright (c) 2017 Urabe, Shyouhei.  All rights reserved.
+#
+# This file is  a part of the programming language  Ruby.  Permission is hereby
+# granted, to  either redistribute and/or  modify this file, provided  that the
+# conditions  mentioned in  the file  COPYING are  met.  Consult  the file  for
+# details.
+
+require_relative '../helpers/c_escape.rb'
+
+class RubyVM::CExpr
+  include RubyVM::CEscape
+
+  attr_reader :__FILE__, :__LINE__, :expr
+
+  def initialize location:, expr:
+    @__FILE__  = location[0]
+    @__LINE__  = location[1]
+    @expr      = expr
+  end
+
+  # blank, in sense of C program.
+  RE = %r'\A{\g<s>*}\z|\A(?<s>\s|/[*][^*]*[*]+([^*/][^*]*[*]+)*/)*\z'
+  if RUBY_VERSION > '2.4' then
+    def blank?
+      RE.match? @expr
+    end
+  else
+    def blank?
+      RE =~ @expr
+    end
+  end
+
+  def inspect
+    sprintf "#<%s:%d %s>", @__FILE__, @__LINE__, @expr
+  end
+end