RegAlloc.Graph.SpillCost

ghc-7.8.3: The GHC API

Safe Haskell | None
Language | Haskell98

RegAlloc.Graph.SpillCost

Synopsis

- type SpillCostRecord = (VirtualReg, Int, Int, Int)
- plusSpillCostRecord :: SpillCostRecord -> SpillCostRecord -> SpillCostRecord
- pprSpillCostRecord :: (VirtualReg -> RegClass) -> (Reg -> SDoc) -> Graph VirtualReg RegClass RealReg -> SpillCostRecord -> SDoc
- type SpillCostInfo = UniqFM SpillCostRecord
- zeroSpillCostInfo :: SpillCostInfo
- plusSpillCostInfo :: SpillCostInfo -> SpillCostInfo -> SpillCostInfo
- slurpSpillCostInfo :: (Outputable instr, Instruction instr) => Platform -> LiveCmmDecl statics instr -> SpillCostInfo
- chooseSpill :: SpillCostInfo -> Graph VirtualReg RegClass RealReg -> VirtualReg
- lifeMapFromSpillCostInfo :: SpillCostInfo -> UniqFM (VirtualReg, Int)

# Documentation

type SpillCostRecord = (VirtualReg, Int, Int, Int) Source

Records the expected cost to spill some regster.

plusSpillCostRecord :: SpillCostRecord -> SpillCostRecord -> SpillCostRecord Source

Add two spill cost records.

pprSpillCostRecord :: (VirtualReg -> RegClass) -> (Reg -> SDoc) -> Graph VirtualReg RegClass RealReg -> SpillCostRecord -> SDoc Source

Show a spill cost record, including the degree from the graph and final calulated spill cost.

type SpillCostInfo = UniqFM SpillCostRecord Source

Map of `SpillCostRecord`

zeroSpillCostInfo :: SpillCostInfo Source

An empty map of spill costs.

plusSpillCostInfo :: SpillCostInfo -> SpillCostInfo -> SpillCostInfo Source

Add two spill cost infos.

slurpSpillCostInfo :: (Outputable instr, Instruction instr) => Platform -> LiveCmmDecl statics instr -> SpillCostInfo Source

Slurp out information used for determining spill costs.

For each vreg, the number of times it was written to, read from, and the number of instructions it was live on entry to (lifetime)

chooseSpill :: SpillCostInfo -> Graph VirtualReg RegClass RealReg -> VirtualReg Source

Choose a node to spill from this graph

lifeMapFromSpillCostInfo :: SpillCostInfo -> UniqFM (VirtualReg, Int) Source

Extract a map of register lifetimes from a `SpillCostInfo`.