Survey of Typed Assembly Language TAL

1
Survey of Typed Assembly Language (TAL)

• Introduction and Motivation
• Conventional untyped compiler lt Typed
  intermediate languages
• Typed intermediate language lt Typed target
  language ( TAL)
• Resources
• From System F to Typed Assembly Language Greg
  Morrisett, David Walker, Karl Crary, and Neal
  Glew
• From System F to Typed Assembly Language
  (Extended version). Technical Report TR97-1651
  Greg Morrisett, David Walker, Karl Crary, and
  Neal Glew
• Intensional Polymorphism in Type-Erasure
  Semantics. Stephanie Weirich , Karl Crary and
  Greg Morrisett
• TALx86 A Realistic Typed Assembly Language Greg
  Morrisett, Karl Crary, Neal Glew, Dan Grossman,
  Richard Samuels, Frederick Smith, David Walker,
  Stephanie Weirich, and Steve Zdancewic
• Structure
• From system F to TAL 4 translations and 5 typed
  calculi
• Extension and practice
• TAL86x, a realistic typed assembly language

2
Compilation of System F to Typed Assembly Language

• Step 1 system F and Continuation Passing style
  (CPS) conversion
• Objective conversion to CPS
• Syntax for ?F(call-by-value variant of system F
  augmented with products and recursion )
• Syntax for?K (target calculus, typed intermediate
  language)
• Whatre completed and changed?
• Names all intermediate computations and
  eliminates the need for a control stack
• All unconditional control transfers are achieved
  via function call
• ?K is almost linear, except for if0
• Functions in ?K invoke continuations using
  void
• Haltt? terminates the computation

Product type

Recursion

Cited from From system F to TAL
3
Compilation of System F to Typed Assembly Language

• Step 2 Simplified Polymorphic Closure
  Conversion
• Objective separate program code from data
• Two steps
• Closure conversion proper
• Approaches Minamide et al / The Definition of
  Standard ML_at_
• Type-passing / Type-erasure interpretation of
  polymorphism
• (types are constructed and passed to
  polymorphic functions at run-time)
• (run-time type information is represented
  by ordinary terms)
• Polymorphic instantiation cannot / can easily be
  handled via substitution
• Requires / Dont require both abstract kinds of
  translucent types
• Cost of Polymorphic closure conversion
• Hoisting lift the closed function code to the
  top of program
• Key point of implementation of the Type-erasure
  interpretation
• Partial applications of functions to type
  arguments to be values
• Eg. ? has type
  
• is treated as a value and has type

Cited from From system F to TAL, Greg
Morrisett, David Walker, Karl Crary, and Neal
Glew _at_ Cited from Intensional Polymorphism in
Type-Erasure Semantics , Karl Crary, Stephanie
Weirich, and Greg Morrisett
4
Compilation of System F to Typed Assembly Language

• Step 3 Explicit Allocation
• Objective allocate spaces for tuples and fill
  them out field by field
• Syntax for?A(similar to ?C )
• Features
• Tuples no long have value form
• Creation of an n-element tuple an allocation
  step n initialization steps
• Eg. Creation of the pair lt?0, ?1 gt

Cited from From system F to TAL
5
Compilation of System F to Typed Assembly Language

• Step 4 Code generation
• Objective convert?A to TAL, mostly syntactic
• TAL syntax

Key technical Difference
TAL program

Cited from From system F to TAL