Lowers the affine index algebra to core arithmetic. More...

#include <mim/plug/affine/phase/lower_index.h>

Inheritance diagram for mim::plug::affine::phase::LowerIndex:

Public Member Functions
	LowerIndex (World &world, flags_t annex)
const Def *	rewrite (const Def *) final
const Def *	rewrite_imm_App (const App *) final
Public Member Functions inherited from mim::RWPhase
	RWPhase (World &world, std::string name, Analysis *analysis=nullptr)
	RWPhase (World &world, flags_t annex, Analysis *analysis=nullptr)
Analysis *	analysis ()
const Analysis *	analysis () const
const Def *	lattice (const Def *old_def)
	Returns the abstract value computed by the associated Analysis for the given old-world Def, or nullptr if no value is available.
virtual bool	analyze ()
	Runs the optional pre-analysis on RWPhase::old_world(), typically to a fixed point, before rewriting begins.
virtual void	rewrite_annex (flags_t, Sym, const Def *)
virtual void	rewrite_external (Def *)
bool	is_bootstrapping () const
	Returns whether we are currently bootstrapping (rewriting annexes).
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
void	invalidate (bool todo=true)
	Signals that another round of fixed-point iteration is required, either as part of.
virtual void	run ()
	Entry point and generates some debug output; invokes Phase::start.
Public Member Functions inherited from mim::Stage
	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.
virtual bool	redirects () const
	If true, Stage::create uses take_resolved().
virtual std::unique_ptr< Stage >	take_resolved ()
	The Stage to use instead; nullptr means elide.
World &	world ()
Driver &	driver ()
Log &	log () const
std::string_view	name () const
flags_t	annex () const
Public Member Functions inherited from mim::Rewriter
	Rewriter (std::unique_ptr< World > &&ptr)
	Rewriter (World &world)
virtual	~Rewriter ()
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_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)

Additional Inherited Members
template<class P, class... Args>
static void	run (Args &&... args)
	Runs a single Phase.
Static Public Member Functions inherited from mim::Stage
static std::unique_ptr< Stage >	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::Stage
std::string	name_
Protected Attributes inherited from mim::Rewriter
std::deque< Def2Def >	old2news_

Detailed Description

Lowers the affine index algebra to core arithmetic.

The opaque affine.index type is rewritten to the wide Idx 0 (i64) carrier, and the index operations are computed with wrap-around (core.Mode::none) arithmetic, so negation/subtraction are correct via two's complement:

affine.constant n ↦ n reinterpreted as an Idx 0,
affine.op.add (a, b) ↦ core.wrap.add none (a, b),
affine.op.sub (a, b) ↦ core.wrap.sub none (a, b),
affine.op.neg a ↦ core.wrap.sub none (0, a),
affine.semiop.mul (a, c) ↦ core.wrap.mul none (a, c).

The affine.map f idxs bridge lowers to: widen each runtime idxs#i : Idx (sin#i) to Idx 0 via core.conv.u, apply the (now core-arithmetic) function f, and narrow each result back to its target Idx (sout#j) via core.conv.u.

The division-based semiops (ceildiv, floordiv, mod) are not yet lowered (they require core.div, which threads a mem.M); they currently raise an error.

Definition at line 22 of file lower_index.h.

Constructor & Destructor Documentation

◆ LowerIndex()

mim::plug::affine::phase::LowerIndex::LowerIndex	(	World &	world,
		flags_t	annex )

inline

Definition at line 24 of file lower_index.h.

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

Member Function Documentation

◆ rewrite()

const Def * mim::plug::affine::phase::LowerIndex::rewrite ( const Def * def )

finalvirtual

Reimplemented from mim::Rewriter.

Definition at line 13 of file lower_index.cpp.

References mim::Axm::isa(), mim::RWPhase::new_world(), mim::Rewriter::rewrite(), and mim::World::type_i64().

Referenced by rewrite_imm_App().

◆ rewrite_imm_App()

const Def * mim::plug::affine::phase::LowerIndex::rewrite_imm_App ( const App * app )

final

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

include/mim/plug/affine/phase/lower_index.h
src/mim/plug/affine/phase/lower_index.cpp