Class: SyntaxTree::YARV::OptNilP

Inherits:
Instruction show all
Defined in:
lib/syntax_tree/yarv/instructions.rb

Overview

### Summary

‘opt_nil_p` is an optimization applied when the method `nil?` is called. It returns true immediately when the receiver is `nil` and defers to the `nil?` method in other cases. It pops the receiver off the stack and pushes on the result.

### Usage

~~~ruby “”.nil? ~~~

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods inherited from Instruction

#branch_targets, #falls_through?, #leaves?, #side_effects?

Constructor Details

#initialize(calldata) ⇒ OptNilP

Returns a new instance of OptNilP.



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# File 'lib/syntax_tree/yarv/instructions.rb', line 3939

def initialize(calldata)
  @calldata = calldata
end

Instance Attribute Details

#calldataObject (readonly)

Returns the value of attribute calldata.



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# File 'lib/syntax_tree/yarv/instructions.rb', line 3937

def calldata
  @calldata
end

Instance Method Details

#==(other) ⇒ Object



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# File 'lib/syntax_tree/yarv/instructions.rb', line 3955

def ==(other)
  other.is_a?(OptNilP) && other.calldata == calldata
end

#call(vm) ⇒ Object



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# File 'lib/syntax_tree/yarv/instructions.rb', line 3975

def call(vm)
  canonical.call(vm)
end

#canonicalObject



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# File 'lib/syntax_tree/yarv/instructions.rb', line 3971

def canonical
  Send.new(calldata, nil)
end

#deconstruct_keys(_keys) ⇒ Object



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# File 'lib/syntax_tree/yarv/instructions.rb', line 3951

def deconstruct_keys(_keys)
  { calldata: calldata }
end

#disasm(fmt) ⇒ Object



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# File 'lib/syntax_tree/yarv/instructions.rb', line 3943

def disasm(fmt)
  fmt.instruction("opt_nil_p", [fmt.calldata(calldata)])
end

#lengthObject



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# File 'lib/syntax_tree/yarv/instructions.rb', line 3959

def length
  2
end

#popsObject



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# File 'lib/syntax_tree/yarv/instructions.rb', line 3963

def pops
  1
end

#pushesObject



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# File 'lib/syntax_tree/yarv/instructions.rb', line 3967

def pushes
  1
end

#to_a(_iseq) ⇒ Object



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# File 'lib/syntax_tree/yarv/instructions.rb', line 3947

def to_a(_iseq)
  [:opt_nil_p, calldata.to_h]
end