delete tool/instruction.rb (2nd try)

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@61784 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

tool/ruby_vm/models/operands_unifications.rb

@@ -0,0 +1,137 @@
+#! /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'
+require_relative '../loaders/opt_operand_def'
+require_relative 'bare_instructions'
+
+class RubyVM::OperandsUnifications < RubyVM::BareInstructions
+  include RubyVM::CEscape
+
+  attr_reader :preamble, :original, :spec
+
+  def initialize location:, signature:
+    name             = signature[0]
+    @original        = RubyVM::BareInstructions.fetch name
+    template         = @original.template
+    parts            = compose location, signature, template[:signature]
+    json             = template.dup
+    json[:location]  = location
+    json[:signature] = parts[:signature]
+    json[:name]      = parts[:name]
+    @preamble        = parts[:preamble]
+    @spec            = parts[:spec]
+    super template: template, **json
+    parts[:vars].each do |v|
+      @variables[v[:name]] ||= v
+    end
+  end
+
+  def operand_shift_of var
+    before = @original.opes.find_index var
+    after  = @opes.find_index var
+    raise "no #{var} for #{@name}" unless before and after
+    return before - after
+  end
+
+  def condition ptr
+    # :FIXME: I'm not sure if this method should be in model?
+    exprs = @spec.each_with_index.map do |(var, val), i|
+      case val when '*' then
+        next nil
+      else
+        type = @original.opes[i][:type]
+        expr = RubyVM::Typemap.typecast_to_VALUE type, val
+        next "#{ptr}[#{i}] == #{expr}"
+      end
+    end
+    exprs.compact!
+    if exprs.size == 1 then
+      return exprs[0]
+    else
+      exprs.map! {|i| "(#{i})" }
+      return exprs.join ' && '
+    end
+  end
+
+  private
+
+  def namegen signature
+    insn, argv = *signature
+    wcary = argv.map do |i|
+      case i when '*' then
+        'WC'
+      else
+        i
+      end
+    end
+    as_tr_cpp [insn, *wcary].join(', ')
+  end
+
+  def compose location, spec, template
+    name    = namegen spec
+    *, argv = *spec
+    opes    = @original.opes
+    if opes.size != argv.size
+      raise sprintf("operand size mismatch for %s (%s's: %d, given: %d)",
+                    name, template[:name], opes.size, argv.size)
+    else
+      src  = []
+      mod  = []
+      spec = []
+      vars = []
+      argv.each_index do |i|
+        j = argv[i]
+        k = opes[i]
+        spec[i] = [k, j]
+        case j when '*' then
+          # operand is from iseq
+          mod << k[:decl]
+        else
+          # operand is inside C
+          vars << k
+          src << {
+            location: location,
+            expr: "    #{k[:name]} = #{j};"
+          }
+        end
+      end
+      src.map! {|i| RubyVM::CExpr.new i }
+      return {
+        name: name,
+        signature: {
+          name: name,
+          ope: mod,
+          pop: template[:pop],
+          ret: template[:ret],
+        },
+        preamble: src,
+        vars: vars,
+        spec: spec
+      }
+    end
+  end
+
+  @instances = RubyVM::OptOperandDef.map do |h|
+    new(**h)
+  end
+
+  def self.to_a
+    @instances
+  end
+
+  def self.each_group
+    to_a.group_by(&:original).each_pair do |k, v|
+      yield k, v
+    end
+  end
+end