mim::SymExprOpt Class Reference

Symbolic Expression Optimization. More...

#include <mim/phase/sym_expr_opt.h>

Inheritance diagram for mim::SymExprOpt:

Public Member Functions
	SymExprOpt (World &world, flags_t annex)
Public Member Functions inherited from mim::RWPhase
bool	is_bootstrapping () const
	Returns whether we are currently bootstrapping (rewriting annexes).
virtual bool	analyze ()
	You can do an optional fixed-point loop on the RWPhase::old_world before rewriting.
	RWPhase (World &world, std::string name, Analysis *analysis=nullptr)
	RWPhase (World &world, flags_t annex, Analysis *analysis=nullptr)
virtual void	rewrite_annex (flags_t, const Def *)
virtual void	rewrite_external (Def *)
World &	world ()=delete
	Hides both and forbids direct access.
World &	old_world ()
	Get old Defs from here.
World &	new_world ()
	Create new Defs into this.
Public Member Functions inherited from mim::Phase
	Phase (World &world, std::string name)
	Phase (World &world, flags_t annex)
bool	todo () const
virtual void	run ()
	Entry point and generates some debug output; invokes Phase::start.
Public Member Functions inherited from mim::Stage
World &	world ()
Driver &	driver ()
Log &	log () const
std::string_view	name () const
flags_t	annex () const
	Stage (World &world, std::string name)
	Stage (World &world, flags_t annex)
virtual	~Stage ()=default
virtual std::unique_ptr< Stage >	recreate ()
	Creates a new instance; needed by a fixed-point PhaseMan.
virtual void	apply (const App *)
	Invoked if your Stage has additional args.
virtual void	apply (Stage &)
	Dito, but invoked by Stage::recreate.
Public Member Functions inherited from mim::Rewriter
	Rewriter (std::unique_ptr< World > &&ptr)
	Rewriter (World &world)
virtual	~Rewriter ()=default
void	reset (std::unique_ptr< World > &&ptr)
void	reset ()
World &	world ()
virtual void	push ()
virtual void	pop ()
virtual const Def *	map (const Def *old_def, const Def *new_def)
const Def *	map (const Def *old_def, Defs new_defs)
const Def *	map (Defs old_defs, const Def *new_def)
const Def *	map (Defs old_defs, Defs new_defs)
virtual const Def *	lookup (const Def *old_def)
	Lookup old_def by searching in reverse through the stack of maps.
virtual const Def *	rewrite (const Def *)
virtual const Def *	rewrite_imm (const Def *)
virtual const Def *	rewrite_mut (Def *)
virtual const Def *	rewrite_stub (Def *, Def *)
virtual DefVec	rewrite (Defs)
virtual const Def *	rewrite_imm_Seq (const Seq *seq)
virtual const Def *	rewrite_mut_Seq (Seq *seq)

Private Member Functions
const Def *	rewrite_imm_App (const App *) final

Additional Inherited Members
template<class P, class... Args>
static void	run (Args &&... args)
	Runs a single Phase.
static auto	create (const Flags2Stages &stages, const Def *def)
template<class A, class P>
static void	hook (Flags2Stages &stages)
Protected Member Functions inherited from mim::RWPhase
void	start () override
	Actual entry.
Protected Attributes inherited from mim::Phase
bool	todo_ = false
	Set to true to indicate that you want to rerun all Phasees in your current fixed-point PhaseMan.
Protected Attributes inherited from mim::Stage
std::string	name_
Protected Attributes inherited from mim::Rewriter
std::deque< Def2Def >	old2news_

Detailed Description

Symbolic Expression Optimization.

Combines:

• Constant propagation with conditional branches but propagates arbitrary expressions
• Detecting equality of variables in programs
• Much in the spirit of Combining analyses, combining optimizations.

Due to MimIR's sea of node structure a number of other optimizations kick in such as arithmetic simplifications and code motion.

Lattice per Lam::var:

 ⊤      ← Keep as is
 |
Bundle  ← Vars that (horizontally) behave the same build a single congruence class
 |
Expr    ← Whole expression is propagated (vertically) through var
 |
 ⊥

Definition at line 27 of file sym_expr_opt.h.

Constructor & Destructor Documentation

SymExprOpt()

mim::SymExprOpt::SymExprOpt ( World & world, flags_t annex )

inline

Definition at line 45 of file sym_expr_opt.h.

References mim::Stage::annex(), mim::RWPhase::RWPhase(), and mim::RWPhase::world().

Member Function Documentation

rewrite_imm_App()

const Def * mim::SymExprOpt::rewrite_imm_App ( const App * old_app )

finalprivate

Definition at line 153 of file sym_expr_opt.cpp.

References mim::App::callee(), mim::Def::isa_mut(), mim::keep(), mim::Rewriter::map(), mim::World::mut_lam(), mim::RWPhase::new_world(), mim::Def::num_vars(), mim::Rewriter::rewrite(), mim::Lam::set(), mim::Phase::todo_, and mim::Def::var().

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The documentation for this class was generated from the following files:

• include/mim/phase/sym_expr_opt.h
• src/mim/phase/sym_expr_opt.cpp