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loop

package
v7.5.0 Latest Latest
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 Go to latest Published: Oct 22, 2026 License: MIT Imports: 7 Imported by: 0

Documentation

Index

Constants

View Source 
const MaxSCEVDepth = 100

Variables

This section is empty.

Functions

func AnalyzeSCEV 

func AnalyzeSCEV(info *LoopInfo)

func CountLoops 

func CountLoops(loops []*Loop) int

func FormatSCEV 

func FormatSCEV(s SCEV, r Renamer, label func(*SCEVAddRec) string) string

FormatSCEV renders s like StringWithRenamer, but passes every recurrence to label, whose result is appended to it. StringWithRenamer prints {start, +, step} alone, so the induction variables of two nested loops -- or the same recurrence in int8 and int64 -- render identically; label lets the caller attach the loop identity and type. A nil label behaves like StringWithRenamer. SCEV implementations other than this package's render through their own StringWithRenamer.

Types

type IVType 

type IVType int
const (
	IVTypeUnknown IVType = iota
	IVTypeBasic
	IVTypeGeometric
)

type InductionVariable 

type InductionVariable struct {
	Phi   *ssa.Phi
	Type  IVType
	Start SCEV
	Step  SCEV
}

type Loop 

type Loop struct {
	Header *ssa.BasicBlock
	// Latch is the source of the loop's first back edge in block order,
	// which can be the header itself. A loop with several back edges (a
	// continue in a for without a post statement) has more latches; Blocks
	// holds the body of all of them.
	Latch      *ssa.BasicBlock
	Blocks     map[*ssa.BasicBlock]bool
	Exits      []*ssa.BasicBlock
	Parent     *Loop
	Children   []*Loop
	Inductions map[*ssa.Phi]*InductionVariable
	TripCount  SCEV
	SCEVCache  map[ssa.Value]SCEV
}

func (*Loop) String 

func (l *Loop) String() string

type LoopInfo 

type LoopInfo struct {
	Function *ssa.Function
	Loops    []*Loop
	LoopMap  map[*ssa.BasicBlock]*Loop
}

func DetectLoops 

func DetectLoops(fn *ssa.Function) *LoopInfo

type Renamer 

type Renamer func(ssa.Value) string

type SCEV 

type SCEV interface {
	ssa.Value
	EvaluateAt(k *big.Int, cache map[SCEV]*big.Int) *big.Int
	IsLoopInvariant(loop *Loop) bool
	String() string
	StringWithRenamer(r Renamer) string
}

func SCEVFromConst 

func SCEVFromConst(c *ssa.Const) SCEV

func ToSCEV 

func ToSCEV(v ssa.Value, loop *Loop) SCEV

type SCEVAddRec 

type SCEVAddRec struct {
	Start SCEV
	Step  SCEV
	Loop  *Loop
	// IntType is the integer type the recurrence is evaluated in, when known.
	// Wraparound makes {1, +, 8} in int8 and in int64 different sequences.
	IntType types.Type
}

func (*SCEVAddRec) EvaluateAt 

func (s *SCEVAddRec) EvaluateAt(k *big.Int, cache map[SCEV]*big.Int) *big.Int

func (*SCEVAddRec) IsLoopInvariant 

func (s *SCEVAddRec) IsLoopInvariant(loop *Loop) bool

func (*SCEVAddRec) Name 

func (s *SCEVAddRec) Name() string

func (*SCEVAddRec) Parent 

func (s *SCEVAddRec) Parent() *ssa.Function

func (*SCEVAddRec) Pos 

func (s *SCEVAddRec) Pos() token.Pos

func (*SCEVAddRec) Referrers 

func (s *SCEVAddRec) Referrers() *[]ssa.Instruction

func (*SCEVAddRec) String 

func (s *SCEVAddRec) String() string

func (*SCEVAddRec) StringWithRenamer 

func (s *SCEVAddRec) StringWithRenamer(r Renamer) string

func (*SCEVAddRec) Type 

func (s *SCEVAddRec) Type() types.Type

type SCEVConstant 

type SCEVConstant struct{ Value *big.Int }

func (*SCEVConstant) EvaluateAt 

func (s *SCEVConstant) EvaluateAt(k *big.Int, cache map[SCEV]*big.Int) *big.Int

func (*SCEVConstant) IsLoopInvariant 

func (s *SCEVConstant) IsLoopInvariant(loop *Loop) bool

func (*SCEVConstant) Name 

func (s *SCEVConstant) Name() string

func (*SCEVConstant) Parent 

func (s *SCEVConstant) Parent() *ssa.Function

func (*SCEVConstant) Pos 

func (s *SCEVConstant) Pos() token.Pos

func (*SCEVConstant) Referrers 

func (s *SCEVConstant) Referrers() *[]ssa.Instruction

func (*SCEVConstant) String 

func (s *SCEVConstant) String() string

func (*SCEVConstant) StringWithRenamer 

func (s *SCEVConstant) StringWithRenamer(r Renamer) string

func (*SCEVConstant) Type 

func (s *SCEVConstant) Type() types.Type

type SCEVGenericExpr 

type SCEVGenericExpr struct {
	Op token.Token
	X  SCEV
	Y  SCEV
}

func (*SCEVGenericExpr) EvaluateAt 

func (s *SCEVGenericExpr) EvaluateAt(k *big.Int, cache map[SCEV]*big.Int) *big.Int

func (*SCEVGenericExpr) IsLoopInvariant 

func (s *SCEVGenericExpr) IsLoopInvariant(loop *Loop) bool

func (*SCEVGenericExpr) Name 

func (s *SCEVGenericExpr) Name() string

func (*SCEVGenericExpr) Parent 

func (s *SCEVGenericExpr) Parent() *ssa.Function

func (*SCEVGenericExpr) Pos 

func (s *SCEVGenericExpr) Pos() token.Pos

func (*SCEVGenericExpr) Referrers 

func (s *SCEVGenericExpr) Referrers() *[]ssa.Instruction

func (*SCEVGenericExpr) String 

func (s *SCEVGenericExpr) String() string

func (*SCEVGenericExpr) StringWithRenamer 

func (s *SCEVGenericExpr) StringWithRenamer(r Renamer) string

func (*SCEVGenericExpr) Type 

func (s *SCEVGenericExpr) Type() types.Type

type SCEVMax 

type SCEVMax struct {
	X SCEV
	Y SCEV
}

func (*SCEVMax) EvaluateAt 

func (s *SCEVMax) EvaluateAt(k *big.Int, cache map[SCEV]*big.Int) *big.Int

func (*SCEVMax) IsLoopInvariant 

func (s *SCEVMax) IsLoopInvariant(loop *Loop) bool

func (*SCEVMax) Name 

func (s *SCEVMax) Name() string

func (*SCEVMax) Parent 

func (s *SCEVMax) Parent() *ssa.Function

func (*SCEVMax) Pos 

func (s *SCEVMax) Pos() token.Pos

func (*SCEVMax) Referrers 

func (s *SCEVMax) Referrers() *[]ssa.Instruction

func (*SCEVMax) String 

func (s *SCEVMax) String() string

func (*SCEVMax) StringWithRenamer 

func (s *SCEVMax) StringWithRenamer(r Renamer) string

func (*SCEVMax) Type 

func (s *SCEVMax) Type() types.Type

type SCEVUnknown 

type SCEVUnknown struct {
	Value       ssa.Value
	IsInvariant bool
}

func (*SCEVUnknown) EvaluateAt 

func (s *SCEVUnknown) EvaluateAt(k *big.Int, cache map[SCEV]*big.Int) *big.Int

func (*SCEVUnknown) IsLoopInvariant 

func (s *SCEVUnknown) IsLoopInvariant(loop *Loop) bool

func (*SCEVUnknown) Name 

func (s *SCEVUnknown) Name() string

func (*SCEVUnknown) Parent 

func (s *SCEVUnknown) Parent() *ssa.Function

func (*SCEVUnknown) Pos 

func (s *SCEVUnknown) Pos() token.Pos

func (*SCEVUnknown) Referrers 

func (s *SCEVUnknown) Referrers() *[]ssa.Instruction

func (*SCEVUnknown) String 

func (s *SCEVUnknown) String() string

func (*SCEVUnknown) StringWithRenamer 

func (s *SCEVUnknown) StringWithRenamer(r Renamer) string

func (*SCEVUnknown) Type 

func (s *SCEVUnknown) Type() types.Type

Source Files

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