Class: SyntaxTree::YARV::SetLocal

Inherits:

Instruction

• Object
• Instruction
• SyntaxTree::YARV::SetLocal

Defined in:

lib/syntax_tree/yarv/instructions.rb

Overview

### Summary

‘setlocal` sets the value of a local variable on a frame determined by the level and index arguments. The level is the number of frames back to look and the index is the index in the local table. It pops the value it is setting off the stack.

### Usage

~~~ruby value = 5 tap { tap { value = 10 } } ~~~

Instance Attribute Summary

• #index ⇒ Object readonly

  Returns the value of attribute index.

• #level ⇒ Object readonly

  Returns the value of attribute level.

Instance Method Summary

• #==(other) ⇒ Object
• #call(vm) ⇒ Object
• #deconstruct_keys(_keys) ⇒ Object
• #disasm(fmt) ⇒ Object
• #initialize(index, level) ⇒ SetLocal constructor

  A new instance of SetLocal.

• #length ⇒ Object
• #pops ⇒ Object
• #to_a(iseq) ⇒ Object

Methods inherited from Instruction

#branch_targets, #canonical, #falls_through?, #leaves?, #pushes, #side_effects?

Constructor Details

#initialize(index, level) ⇒ SetLocal

Returns a new instance of SetLocal.

# File 'lib/syntax_tree/yarv/instructions.rb', line 5161

def initialize(index, level)
  @index = index
  @level = level
end

Instance Attribute Details

#index ⇒ Object (readonly)

Returns the value of attribute index.

# File 'lib/syntax_tree/yarv/instructions.rb', line 5159

def index
  @index
end

#level ⇒ Object (readonly)

Returns the value of attribute level.

# File 'lib/syntax_tree/yarv/instructions.rb', line 5159

def level
  @level
end

Instance Method Details

#==(other) ⇒ Object

# File 'lib/syntax_tree/yarv/instructions.rb', line 5180

def ==(other)
  other.is_a?(SetLocal) && other.index == index && other.level == level
end

#call(vm) ⇒ Object

# File 'lib/syntax_tree/yarv/instructions.rb', line 5192

def call(vm)
  vm.local_set(index, level, vm.pop)
end

#deconstruct_keys(_keys) ⇒ Object

# File 'lib/syntax_tree/yarv/instructions.rb', line 5176

def deconstruct_keys(_keys)
  { index: index, level: level }
end

#disasm(fmt) ⇒ Object

# File 'lib/syntax_tree/yarv/instructions.rb', line 5166

def disasm(fmt)
  fmt.instruction("setlocal", [fmt.local(index, explicit: level)])
end

#length ⇒ Object

# File 'lib/syntax_tree/yarv/instructions.rb', line 5184

def length
  3
end

#pops ⇒ Object

# File 'lib/syntax_tree/yarv/instructions.rb', line 5188

def pops
  1
end

#to_a(iseq) ⇒ Object

# File 'lib/syntax_tree/yarv/instructions.rb', line 5170

def to_a(iseq)
  current = iseq
  level.times { current = current.parent_iseq }
  [:setlocal, current.local_table.offset(index), level]
end