Safe Haskell	None
Language	Haskell2010

RegAlloc.Graph.ArchBase

Description

Utils for calculating general worst, bound, squeese and free, functions.

as per: "A Generalized Algorithm for Graph-Coloring Register Allocation" Michael Smith, Normal Ramsey, Glenn Holloway. PLDI 2004

These general versions are not used in GHC proper because they are too slow. Instead, hand written optimised versions are provided for each architecture in MachRegs*.hs

This code is here because we can test the architecture specific code against it.

Synopsis

data RegClass
- = ClassG32
- | ClassG16
- | ClassG8
- | ClassF64
data Reg
- = Reg RegClass Int
- | RegSub RegSub Reg
data RegSub
- = SubL16
- | SubL8
- | SubL8H
worst :: (RegClass -> UniqSet Reg) -> (Reg -> UniqSet Reg) -> Int -> RegClass -> RegClass -> Int
bound :: (RegClass -> UniqSet Reg) -> (Reg -> UniqSet Reg) -> RegClass -> [RegClass] -> Int
squeese :: (RegClass -> UniqSet Reg) -> (Reg -> UniqSet Reg) -> RegClass -> [(Int, RegClass)] -> Int

Documentation

data RegClass Source #

Constructors

ClassG32
ClassG16
ClassG8
ClassF64

Instances

Enum RegClass #
Instance details Defined in RegAlloc.Graph.ArchBase Methods succ :: RegClass -> RegClass Source # pred :: RegClass -> RegClass Source # toEnum :: Int -> RegClass Source # fromEnum :: RegClass -> Int Source # enumFrom :: RegClass -> [RegClass] Source # enumFromThen :: RegClass -> RegClass -> [RegClass] Source # enumFromTo :: RegClass -> RegClass -> [RegClass] Source # enumFromThenTo :: RegClass -> RegClass -> RegClass -> [RegClass] Source #
Eq RegClass #
Instance details Defined in RegAlloc.Graph.ArchBase Methods (==) :: RegClass -> RegClass -> Bool # (/=) :: RegClass -> RegClass -> Bool #
Show RegClass #
Instance details Defined in RegAlloc.Graph.ArchBase Methods showsPrec :: Int -> RegClass -> ShowS Source # show :: RegClass -> String Source # showList :: [RegClass] -> ShowS Source #

data Reg Source #

A register of some class

Constructors

Reg RegClass Int
RegSub RegSub Reg

Instances

Eq Reg #
Instance details Defined in RegAlloc.Graph.ArchBase Methods (==) :: Reg -> Reg -> Bool # (/=) :: Reg -> Reg -> Bool #
Show Reg #
Instance details Defined in RegAlloc.Graph.ArchBase Methods showsPrec :: Int -> Reg -> ShowS Source # show :: Reg -> String Source # showList :: [Reg] -> ShowS Source #
Uniquable Reg #	so we can put regs in UniqSets
Instance details Defined in RegAlloc.Graph.ArchBase Methods getUnique :: Reg -> Unique Source #

data RegSub Source #

A subcomponent of another register

Constructors

SubL16
SubL8
SubL8H

Instances

Enum RegSub #
Instance details Defined in RegAlloc.Graph.ArchBase Methods succ :: RegSub -> RegSub Source # pred :: RegSub -> RegSub Source # toEnum :: Int -> RegSub Source # fromEnum :: RegSub -> Int Source # enumFrom :: RegSub -> [RegSub] Source # enumFromThen :: RegSub -> RegSub -> [RegSub] Source # enumFromTo :: RegSub -> RegSub -> [RegSub] Source # enumFromThenTo :: RegSub -> RegSub -> RegSub -> [RegSub] Source #
Eq RegSub #
Instance details Defined in RegAlloc.Graph.ArchBase Methods (==) :: RegSub -> RegSub -> Bool # (/=) :: RegSub -> RegSub -> Bool #
Ord RegSub #
Instance details Defined in RegAlloc.Graph.ArchBase Methods compare :: RegSub -> RegSub -> Ordering # (<) :: RegSub -> RegSub -> Bool # (<=) :: RegSub -> RegSub -> Bool # (>) :: RegSub -> RegSub -> Bool # (>=) :: RegSub -> RegSub -> Bool # max :: RegSub -> RegSub -> RegSub # min :: RegSub -> RegSub -> RegSub #
Show RegSub #
Instance details Defined in RegAlloc.Graph.ArchBase Methods showsPrec :: Int -> RegSub -> ShowS Source # show :: RegSub -> String Source # showList :: [RegSub] -> ShowS Source #

worst :: (RegClass -> UniqSet Reg) -> (Reg -> UniqSet Reg) -> Int -> RegClass -> RegClass -> Int Source #

Worst case displacement

a node N of classN has some number of neighbors, all of which are from classC.

(worst neighbors classN classC) is the maximum number of potential colors for N that can be lost by coloring its neighbors.

This should be hand coded/cached for each particular architecture, because the compute time is very long..

bound :: (RegClass -> UniqSet Reg) -> (Reg -> UniqSet Reg) -> RegClass -> [RegClass] -> Int Source #

For a node N of classN and neighbors of classesC (bound classN classesC) is the maximum number of potential colors for N that can be lost by coloring its neighbors.

squeese :: (RegClass -> UniqSet Reg) -> (Reg -> UniqSet Reg) -> RegClass -> [(Int, RegClass)] -> Int Source #

The total squeese on a particular node with a list of neighbors.

A version of this should be constructed for each particular architecture, possibly including uses of bound, so that alised registers don't get counted twice, as per the paper.