vmm

Documentation

Overview

Package vmm - Emacs Lisp "virtual machine model".

Provides various kinds of information about execution environment which is useful for optimizations and code generation.

Index

• func FuncIsThrowing(name string) bool
• func InstrCallCost(name string) int
• type StructRepr
  • func StructReprOf(typ *types.Struct) StructRepr

Functions

func FuncIsThrowing

func FuncIsThrowing(name string) bool

FuncIsThrowing returns true if function with given name is known to be "throwing" (interrupts normal execution flow).

func InstrCallCost

func InstrCallCost(name string) int

InstrCallCost returns special function call cost. Zero value means that function has no dedicated instruction available.

Types

type StructRepr

type StructRepr int

StructRepr specifies runtime object representation (data layout).

const (
	// StructEmpty - zero size object.
	StructEmpty StructRepr = iota
	// StructUnit - single attribute struct.
	// Represented as (cons X nil).
	StructUnit
	// StructCons - struct of [2, consReprThreshold] attributes.
	// Represented as improper list (chained conses).
	StructCons
	// StructVec - struct which has more that consReprThreshold+1 attributes.
	// Represented as vector.
	StructVec
)

func StructReprOf

func StructReprOf(typ *types.Struct) StructRepr

StructReprOf returns enumeration that describes object representation.