gc

package
v0.0.0-...-21c4e99 Latest Latest
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This package is not in the latest version of its module.

 Go to latest Published: Nov 2, 2015 License: BSD-3-Clause Imports: 20 Imported by: 0

Documentation

Index

Constants

View Source 
const (
	WORDSIZE  = 4
	WORDBITS  = 32
	WORDMASK  = WORDBITS - 1
	WORDSHIFT = 5
)
View Source 
const (
	EscFuncUnknown = 0 + iota
	EscFuncPlanned
	EscFuncStarted
	EscFuncTagged
)
View Source 
const (
	EscUnknown = iota
	EscNone    // Does not escape to heap, result, or parameters.
	EscReturn  // Is returned or reachable from returned.
	EscScope   // Allocated in an inner loop scope, assigned to an outer loop scope,
	// which allows the construction of non-escaping but arbitrarily large linked
	// data structures (i.e., not eligible for allocation in a fixed-size stack frame).
	EscHeap           // Reachable from the heap
	EscNever          // By construction will not escape.
	EscBits           = 3
	EscMask           = (1 << EscBits) - 1
	EscContentEscapes = 1 << EscBits // value obtained by indirect of parameter escapes to heap
	EscReturnBits     = EscBits + 1
)

Escape constants are numbered in order of increasing "escapiness" to help make inferences be monotonic. With the exception of EscNever which is sticky, eX < eY means that eY is more exposed than eX, and hence replaces it in a conservative analysis.

View Source 
const (
	FErr = iota
	FDbg
	FExp
	FTypeId
)

Format conversions 

	%L int		Line numbers

	%E int		etype values (aka 'Kind')

	%O int		Node Opcodes
		Flags: "%#O": print go syntax. (automatic unless fmtmode == FDbg)

	%J Node*	Node details
		Flags: "%hJ" suppresses things not relevant until walk.

	%V Val*		Constant values

	%S Sym*		Symbols
		Flags: +,- #: mode (see below)
			"%hS"	unqualified identifier in any mode
			"%hhS"  in export mode: unqualified identifier if exported, qualified if not

	%T Type*	Types
		Flags: +,- #: mode (see below)
			'l' definition instead of name.
			'h' omit "func" and receiver in function types
			'u' (only in -/Sym mode) print type identifiers wit package name instead of prefix.

	%N Node*	Nodes
		Flags: +,- #: mode (see below)
			'h' (only in +/debug mode) suppress recursion
			'l' (only in Error mode) print "foo (type Bar)"

	%H NodeList*	NodeLists
		Flags: those of %N
			','  separate items with ',' instead of ';'

  In mparith2.go and mparith3.go:
		%B Mpint*	Big integers
		%F Mpflt*	Big floats

  %S, %T and %N obey use the following flags to set the format mode:
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const (
	NHUNK           = 50000
	BUFSIZ          = 8192
	NSYMB           = 500
	NHASH           = 1024
	MAXALIGN        = 7
	UINF            = 100
	PRIME1          = 3
	BADWIDTH        = -1000000000
	MaxStackVarSize = 10 * 1024 * 1024
)

The parser's maximum stack size. We have to use a #define macro here since yacc or bison will check for its definition and use a potentially smaller value if it is undefined.

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const (
	// These values are known by runtime.
	// The MEMx and NOEQx values must run in parallel.  See algtype.
	AMEM = iota
	AMEM0
	AMEM8
	AMEM16
	AMEM32
	AMEM64
	AMEM128
	ANOEQ
	ANOEQ0
	ANOEQ8
	ANOEQ16
	ANOEQ32
	ANOEQ64
	ANOEQ128
	ASTRING
	AINTER
	ANILINTER
	ASLICE
	AFLOAT32
	AFLOAT64
	ACPLX64
	ACPLX128
	AUNK = 100
)
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const (
	// Maximum size in bits for Mpints before signalling
	// overflow and also mantissa precision for Mpflts.
	Mpprec = 512
	// Turn on for constant arithmetic debugging output.
	Mpdebug = false
)
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const (
	SymExport   = 1 << 0 // to be exported
	SymPackage  = 1 << 1
	SymExported = 1 << 2 // already written out by export
	SymUniq     = 1 << 3
	SymSiggen   = 1 << 4
	SymAsm      = 1 << 5
	SymAlgGen   = 1 << 6
)
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const (
	Txxx = iota

	TINT8
	TUINT8
	TINT16
	TUINT16
	TINT32
	TUINT32
	TINT64
	TUINT64
	TINT
	TUINT
	TUINTPTR

	TCOMPLEX64
	TCOMPLEX128

	TFLOAT32
	TFLOAT64

	TBOOL

	TPTR32
	TPTR64

	TFUNC
	TARRAY
	T_old_DARRAY // Doesn't seem to be used in existing code. Used now for Isddd export (see bexport.go). TODO(gri) rename.
	TSTRUCT
	TCHAN
	TMAP
	TINTER
	TFORW
	TFIELD
	TANY
	TSTRING
	TUNSAFEPTR

	// pseudo-types for literals
	TIDEAL
	TNIL
	TBLANK

	// pseudo-type for frame layout
	TFUNCARGS
	TCHANARGS
	TINTERMETH

	NTYPE
)
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const (
	// types of channel
	// must match ../../pkg/nreflect/type.go:/Chandir
	Cxxx  = 0
	Crecv = 1 << 0
	Csend = 1 << 1
	Cboth = Crecv | Csend
)
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const (
	Etop      = 1 << 1 // evaluated at statement level
	Erv       = 1 << 2 // evaluated in value context
	Etype     = 1 << 3
	Ecall     = 1 << 4  // call-only expressions are ok
	Efnstruct = 1 << 5  // multivalue function returns are ok
	Eiota     = 1 << 6  // iota is ok
	Easgn     = 1 << 7  // assigning to expression
	Eindir    = 1 << 8  // indirecting through expression
	Eaddr     = 1 << 9  // taking address of expression
	Eproc     = 1 << 10 // inside a go statement
	Ecomplit  = 1 << 11 // type in composite literal
)
View Source 
const (
	// Pseudo-op, like TEXT, GLOBL, TYPE, PCDATA, FUNCDATA.
	Pseudo = 1 << 1

	// There's nothing to say about the instruction,
	// but it's still okay to see.
	OK = 1 << 2

	// Size of right-side write, or right-side read if no write.
	SizeB = 1 << 3
	SizeW = 1 << 4
	SizeL = 1 << 5
	SizeQ = 1 << 6
	SizeF = 1 << 7
	SizeD = 1 << 8

	// Left side (Prog.from): address taken, read, write.
	LeftAddr  = 1 << 9
	LeftRead  = 1 << 10
	LeftWrite = 1 << 11

	// Register in middle (Prog.reg); only ever read. (arm, ppc64)
	RegRead    = 1 << 12
	CanRegRead = 1 << 13

	// Right side (Prog.to): address taken, read, write.
	RightAddr  = 1 << 14
	RightRead  = 1 << 15
	RightWrite = 1 << 16

	// Instruction kinds
	Move  = 1 << 17 // straight move
	Conv  = 1 << 18 // size conversion
	Cjmp  = 1 << 19 // conditional jump
	Break = 1 << 20 // breaks control flow (no fallthrough)
	Call  = 1 << 21 // function call
	Jump  = 1 << 22 // jump
	Skip  = 1 << 23 // data instruction

	// Set, use, or kill of carry bit.
	// Kill means we never look at the carry bit after this kind of instruction.
	SetCarry  = 1 << 24
	UseCarry  = 1 << 25
	KillCarry = 1 << 26

	// Special cases for register use. (amd64, 386)
	ShiftCX  = 1 << 27 // possible shift by CX
	ImulAXDX = 1 << 28 // possible multiply into DX:AX

	// Instruction updates whichever of from/to is type D_OREG. (ppc64)
	PostInc = 1 << 29
)
View Source 
const (
	UNVISITED = 0
	VISITED   = 1
)
View Source 
const (
	H0 = 2166136261
	Hp = 16777619
)

FNV-1 hash function constants.

View Source 
const (
	BUCKETSIZE = 8
	MAXKEYSIZE = 128
	MAXVALSIZE = 128
)

Builds a type representing a Bucket structure for the given map type. This type is not visible to users - we include only enough information to generate a correct GC program for it. Make sure this stays in sync with ../../runtime/hashmap.go!

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const (
	BITS = 3
	NVAR = BITS * 64
)
View Source 
const (
	CLOAD = 5 // cost of load
	CREF  = 5 // cost of reference if not registerized
	LOOP  = 3 // loop execution count (applied in popt.go)
)

Cost parameters

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const (
	InitNotStarted = 0
	InitDone       = 1
	InitPending    = 2
)

static initialization

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const (
	MODEDYNAM = 1
	MODECONST = 2
)
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const (
	OXXX = Op(iota)

	// names
	ONAME    // var, const or func name
	ONONAME  // unnamed arg or return value: f(int, string) (int, error) { etc }
	OTYPE    // type name
	OPACK    // import
	OLITERAL // literal

	// expressions
	OADD             // Left + Right
	OSUB             // Left - Right
	OOR              // Left | Right
	OXOR             // Left ^ Right
	OADDSTR          // Left + Right (string addition)
	OADDR            // &Left
	OANDAND          // Left && Right
	OAPPEND          // append(List)
	OARRAYBYTESTR    // Type(Left) (Type is string, Left is a []byte)
	OARRAYBYTESTRTMP // Type(Left) (Type is string, Left is a []byte, ephemeral)
	OARRAYRUNESTR    // Type(Left) (Type is string, Left is a []rune)
	OSTRARRAYBYTE    // Type(Left) (Type is []byte, Left is a string)
	OSTRARRAYBYTETMP // Type(Left) (Type is []byte, Left is a string, ephemeral)
	OSTRARRAYRUNE    // Type(Left) (Type is []rune, Left is a string)
	OAS              // Left = Right or (if Colas=true) Left := Right
	OAS2             // List = Rlist (x, y, z = a, b, c)
	OAS2FUNC         // List = Rlist (x, y = f())
	OAS2RECV         // List = Rlist (x, ok = <-c)
	OAS2MAPR         // List = Rlist (x, ok = m["foo"])
	OAS2DOTTYPE      // List = Rlist (x, ok = I.(int))
	OASOP            // Left Etype= Right (x += y)
	OASWB            // Left = Right (with write barrier)
	OCALL            // Left(List) (function call, method call or type conversion)
	OCALLFUNC        // Left(List) (function call f(args))
	OCALLMETH        // Left(List) (direct method call x.Method(args))
	OCALLINTER       // Left(List) (interface method call x.Method(args))
	OCALLPART        // Left.Right (method expression x.Method, not called)
	OCAP             // cap(Left)
	OCLOSE           // close(Left)
	OCLOSURE         // func Type { Body } (func literal)
	OCMPIFACE        // Left Etype Right (interface comparison, x == y or x != y)
	OCMPSTR          // Left Etype Right (string comparison, x == y, x < y, etc)
	OCOMPLIT         // Right{List} (composite literal, not yet lowered to specific form)
	OMAPLIT          // Type{List} (composite literal, Type is map)
	OSTRUCTLIT       // Type{List} (composite literal, Type is struct)
	OARRAYLIT        // Type{List} (composite literal, Type is array or slice)
	OPTRLIT          // &Left (left is composite literal)
	OCONV            // Type(Left) (type conversion)
	OCONVIFACE       // Type(Left) (type conversion, to interface)
	OCONVNOP         // Type(Left) (type conversion, no effect)
	OCOPY            // copy(Left, Right)
	ODCL             // var Left (declares Left of type Left.Type)

	// Used during parsing but don't last.
	ODCLFUNC  // func f() or func (r) f()
	ODCLFIELD // struct field, interface field, or func/method argument/return value.
	ODCLCONST // const pi = 3.14
	ODCLTYPE  // type Int int

	ODELETE    // delete(Left, Right)
	ODOT       // Left.Right (Left is of struct type)
	ODOTPTR    // Left.Right (Left is of pointer to struct type)
	ODOTMETH   // Left.Right (Left is non-interface, Right is method name)
	ODOTINTER  // Left.Right (Left is interface, Right is method name)
	OXDOT      // Left.Right (before rewrite to one of the preceding)
	ODOTTYPE   // Left.Right or Left.Type (.Right during parsing, .Type once resolved)
	ODOTTYPE2  // Left.Right or Left.Type (.Right during parsing, .Type once resolved; on rhs of OAS2DOTTYPE)
	OEQ        // Left == Right
	ONE        // Left != Right
	OLT        // Left < Right
	OLE        // Left <= Right
	OGE        // Left >= Right
	OGT        // Left > Right
	OIND       // *Left
	OINDEX     // Left[Right] (index of array or slice)
	OINDEXMAP  // Left[Right] (index of map)
	OKEY       // Left:Right (key:value in struct/array/map literal, or slice index pair)
	OPARAM     // variant of ONAME for on-stack copy of a parameter or return value that escapes.
	OLEN       // len(Left)
	OMAKE      // make(List) (before type checking converts to one of the following)
	OMAKECHAN  // make(Type, Left) (type is chan)
	OMAKEMAP   // make(Type, Left) (type is map)
	OMAKESLICE // make(Type, Left, Right) (type is slice)
	OMUL       // Left * Right
	ODIV       // Left / Right
	OMOD       // Left % Right
	OLSH       // Left << Right
	ORSH       // Left >> Right
	OAND       // Left & Right
	OANDNOT    // Left &^ Right
	ONEW       // new(Left)
	ONOT       // !Left
	OCOM       // ^Left
	OPLUS      // +Left
	OMINUS     // -Left
	OOROR      // Left || Right
	OPANIC     // panic(Left)
	OPRINT     // print(List)
	OPRINTN    // println(List)
	OPAREN     // (Left)
	OSEND      // Left <- Right
	OSLICE     // Left[Right.Left : Right.Right] (Left is untypechecked or slice; Right.Op==OKEY)
	OSLICEARR  // Left[Right.Left : Right.Right] (Left is array)
	OSLICESTR  // Left[Right.Left : Right.Right] (Left is string)
	OSLICE3    // Left[R.Left : R.R.Left : R.R.R] (R=Right; Left is untypedchecked or slice; R.Op and R.R.Op==OKEY)
	OSLICE3ARR // Left[R.Left : R.R.Left : R.R.R] (R=Right; Left is array; R.Op and R.R.Op==OKEY)
	ORECOVER   // recover()
	ORECV      // <-Left
	ORUNESTR   // Type(Left) (Type is string, Left is rune)
	OSELRECV   // Left = <-Right.Left: (appears as .Left of OCASE; Right.Op == ORECV)
	OSELRECV2  // List = <-Right.Left: (apperas as .Left of OCASE; count(List) == 2, Right.Op == ORECV)
	OIOTA      // iota
	OREAL      // real(Left)
	OIMAG      // imag(Left)
	OCOMPLEX   // complex(Left, Right)

	// statements
	OBLOCK    // { List } (block of code)
	OBREAK    // break
	OCASE     // case List: Nbody (select case after processing; List==nil means default)
	OXCASE    // case List: Nbody (select case before processing; List==nil means default)
	OCONTINUE // continue
	ODEFER    // defer Left (Left must be call)
	OEMPTY    // no-op (empty statement)
	OFALL     // fallthrough (after processing)
	OXFALL    // fallthrough (before processing)
	OFOR      // for Ninit; Left; Right { Nbody }
	OGOTO     // goto Left
	OIF       // if Ninit; Left { Nbody } else { Rlist }
	OLABEL    // Left:
	OPROC     // go Left (Left must be call)
	ORANGE    // for List = range Right { Nbody }
	ORETURN   // return List
	OSELECT   // select { List } (List is list of OXCASE or OCASE)
	OSWITCH   // switch Ninit; Left { List } (List is a list of OXCASE or OCASE)
	OTYPESW   // List = Left.(type) (appears as .Left of OSWITCH)

	// types
	OTCHAN   // chan int
	OTMAP    // map[string]int
	OTSTRUCT // struct{}
	OTINTER  // interface{}
	OTFUNC   // func()
	OTARRAY  // []int, [8]int, [N]int or [...]int

	// misc
	ODDD        // func f(args ...int) or f(l...) or var a = [...]int{0, 1, 2}.
	ODDDARG     // func f(args ...int), introduced by escape analysis.
	OINLCALL    // intermediary representation of an inlined call.
	OEFACE      // itable and data words of an empty-interface value.
	OITAB       // itable word of an interface value.
	OSPTR       // base pointer of a slice or string.
	OCLOSUREVAR // variable reference at beginning of closure function
	OCFUNC      // reference to c function pointer (not go func value)
	OCHECKNIL   // emit code to ensure pointer/interface not nil
	OVARKILL    // variable is dead

	// thearch-specific registers
	OREGISTER // a register, such as AX.
	OINDREG   // offset plus indirect of a register, such as 8(SP).

	// arch-specific opcodes
	OCMP    // compare: ACMP.
	ODEC    // decrement: ADEC.
	OINC    // increment: AINC.
	OEXTEND // extend: ACWD/ACDQ/ACQO.
	OHMUL   // high mul: AMUL/AIMUL for unsigned/signed (OMUL uses AIMUL for both).
	OLROT   // left rotate: AROL.
	ORROTC  // right rotate-carry: ARCR.
	ORETJMP // return to other function
	OPS     // compare parity set (for x86 NaN check)
	OPC     // compare parity clear (for x86 NaN check)
	OSQRT   // sqrt(float64), on systems that have hw support
	OGETG   // runtime.getg() (read g pointer)

	OEND
)

Node ops.

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const (
	ArhdrSize = 60
)

architecture-independent object file output

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const (
	EOF = -1
)
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const LANDAND = 57376
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const LANDNOT = 57377
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const LASOP = 57347
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const LBODY = 57378
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const LBREAK = 57349
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const LCASE = 57350
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const LCHAN = 57351
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const LCOLAS = 57348
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const LCOMM = 57379
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const LCONST = 57352
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const LCONTINUE = 57353
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const LDDD = 57354
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const LDEC = 57380
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const LDEFAULT = 57355
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const LDEFER = 57356
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const LELSE = 57357
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const LEQ = 57381
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const LFALL = 57358
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const LFOR = 57359
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const LFUNC = 57360
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const LGE = 57382
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const LGO = 57361
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const LGOTO = 57362
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const LGT = 57383
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const LIF = 57363
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const LIGNORE = 57384
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const LIMPORT = 57364
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const LINC = 57385
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const LINTERFACE = 57365
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const LLE = 57386
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const LLITERAL = 57346
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const LLSH = 57387
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const LLT = 57388
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const LMAP = 57366
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const LNAME = 57367
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const LNE = 57389
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const LOROR = 57390
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const LPACKAGE = 57368
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const LRANGE = 57369
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const LRETURN = 57370
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const LRSH = 57391
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const LSELECT = 57371
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const LSTRUCT = 57372
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const LSWITCH = 57373
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const LTYPE = 57374
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const LVAR = 57375
View Source 
const MaxFlowProg = 50000

MaxFlowProg is the maximum size program (counted in instructions) for which the flow code will build a graph. Functions larger than this limit will not have flow graphs and consequently will not be optimized.

View Source 
const MaxRgn = 6000

The Plan 9 C compilers used a limit of 600 regions, but the yacc-generated parser in y.go has 3100 regions. We set MaxRgn large enough to handle that. There's not a huge cost to having too many regions: the main processing traces the live area for each variable, which is limited by the number of variables times the area, not the raw region count. If there are many regions, they are almost certainly small and easy to trace. The only operation that scales with region count is the sorting by cost, which uses sort.Sort and is therefore guaranteed n log n.

View Source 
const (
	MinLevel = -2
)

There appear to be some loops in the escape graph, causing arbitrary recursion into deeper and deeper levels. Cut this off safely by making minLevel sticky: once you get that deep, you cannot go down any further but you also cannot go up any further. This is a conservative fix. Making minLevel smaller (more negative) would handle more complex chains of indirections followed by address-of operations, at the cost of repeating the traversal once for each additional allowed level when a loop is encountered. Using -2 suffices to pass all the tests we have written so far, which we assume matches the level of complexity we want the escape analysis code to handle.

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const NotPackage = 57392
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const NotParen = 57393
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const PreferToRightParen = 57394

Variables

View Source 
var (
	Isptr [NTYPE]bool

	Isint     [NTYPE]bool
	Isfloat   [NTYPE]bool
	Iscomplex [NTYPE]bool
	Issigned  [NTYPE]bool
)
View Source 
var (
	Debug_append int
	Debug_panic  int
	Debug_slice  int
	Debug_wb     int
)
View Source 
var Array_array int // runtime offsetof(Array,array) - same for String

note this is the runtime representation of the compilers arrays.

typedef struct { // must not move anything 

	uchar	array[8];	// pointer to data
	uchar	nel[4];		// number of elements
	uchar	cap[4];		// allocated number of elements
} Array;
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var Array_cap int // runtime offsetof(Array,cap)
View Source 
var Array_nel int // runtime offsetof(Array,nel) - same for String
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var Ctxt *obj.Link
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var Debug [256]int
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var Debug_checknil int
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var (
	Debug_export int // if set, print debugging information about export data

)
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var Debug_gcprog int // set by -d gcprog
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var Debug_typeassert int
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var Disable_checknil int
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var Funcdepth int32
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var Maxarg int64
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var Maxintval [NTYPE]*Mpint
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var Minintval [NTYPE]*Mpint
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var Nacl bool
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var Pc *obj.Prog
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var Simtype [NTYPE]EType
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var Stksize int64 // stack size for current frame
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var Types [NTYPE]*Type
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var Widthint int
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var Widthptr int
View Source 
var Widthreg int

Functions

func Afunclit 

func Afunclit(a *obj.Addr, n *Node)

func Agen 

func Agen(n *Node, res *Node)

generate: 

res = &n;

The generated code checks that the result is not nil.

func Agenr 

func Agenr(n *Node, a *Node, res *Node)

allocate a register (reusing res if possible) and generate 

a = &n

The caller must call Regfree(a). The generated code checks that the result is not nil.

func Anyregalloc 

func Anyregalloc() bool

func Argsize 

func Argsize(t *Type) int

compute total size of f's in/out arguments.

func AtExit 

func AtExit(f func())

func Bconv 

func Bconv(xval *Mpint, flag int) string

func Bgen 

func Bgen(n *Node, wantTrue bool, likely int, to *obj.Prog)

Bgen generates code for branches: 

if n == wantTrue {
	goto to
}

func Bitno 

func Bitno(b uint64) int

Bitno reports the lowest index of a 1 bit in b. It calls Fatalf if there is no 1 bit.

func Bputname 

func Bputname(b *obj.Biobuf, s *obj.LSym)

func Bvgen 

func Bvgen(n, res *Node, wantTrue bool)

Bvgen generates code for calculating boolean values: 

res = n == wantTrue

func Cgen 

func Cgen(n, res *Node)

generate: 

res = n;

simplifies and calls Thearch.Gmove. if wb is true, need to emit write barriers.

func Cgen_As2dottype 

func Cgen_As2dottype(n, res, resok *Node)

generate: 

res, resok = x.(T)

n.Left is x n.Type is T

func Cgen_as 

func Cgen_as(nl, nr *Node)

func Cgen_as_wb 

func Cgen_as_wb(nl, nr *Node, wb bool)

func Cgen_checknil 

func Cgen_checknil(n *Node)

func Cgen_eface 

func Cgen_eface(n *Node, res *Node)

generate: 

res = iface{typ, data}

n->left is typ n->right is data

func Cgenr 

func Cgenr(n *Node, a *Node, res *Node)

allocate a register (reusing res if possible) and generate 

a = n

The caller must call Regfree(a).

func Clearp 

func Clearp(p *obj.Prog)

func Clearslim 

func Clearslim(n *Node)

clearslim generates code to zero a slim node.

func Complexgen 

func Complexgen(n *Node, res *Node)

func Complexmove 

func Complexmove(f *Node, t *Node)

func Complexop 

func Complexop(n *Node, res *Node) bool

func Componentgen 

func Componentgen(nr, nl *Node) bool

Componentgen copies a composite value by moving its individual components. Slices, strings and interfaces are supported. Small structs or arrays with elements of basic type are also supported. nr is nil when assigning a zero value.

func Convlit 

func Convlit(np **Node, t *Type)

convert n, if literal, to type t. implicit conversion.

func Datastring 

func Datastring(s string, a *obj.Addr)

func Dotoffset 

func Dotoffset(n *Node, oary []int64, nn **Node) int

gather series of offsets >=0 is direct addressed field <0 is pointer to next field (+1)

func Dump 

func Dump(s string, n *Node)

func Dumpit 

func Dumpit(str string, r0 *Flow, isreg int)

func Econv 

func Econv(et EType) string

Fmt "%E": etype

func Eqtype 

func Eqtype(t1 *Type, t2 *Type) bool

Return 1 if t1 and t2 are identical, following the spec rules.

Any cyclic type must go through a named type, and if one is named, it is only identical to the other if they are the same pointer (t1 == t2), so there's no chance of chasing cycles ad infinitum, so no need for a depth counter.

func Exit 

func Exit(code int)

func Export 

func Export(out *obj.Biobuf, trace bool) int

Export writes the export data for localpkg to out and returns the number of bytes written.

func Fatalf 

func Fatalf(fmt_ string, args ...interface{})

func Fconv 

func Fconv(fvp *Mpflt, flag int) string

func Fixlargeoffset 

func Fixlargeoffset(n *Node)

func Flowend 

func Flowend(graph *Graph)

func Flusherrors 

func Flusherrors()

func Gbranch 

func Gbranch(as int, t *Type, likely int) *obj.Prog

func Genlist 

func Genlist(l *NodeList)

compile statements

func GetReg 

func GetReg(r int) int

func Ginscall 

func Ginscall(f *Node, proc int)

generate: 

call f
proc=-1	normal call but no return
proc=0	normal call
proc=1	goroutine run in new proc
proc=2	defer call save away stack
proc=3	normal call to C pointer (not Go func value)

func Gvardef 

func Gvardef(n *Node)

func Hconv 

func Hconv(l *NodeList, flag int) string

Fmt '%H': NodeList. Flags: all those of %N plus ',': separate with comma's instead of semicolons.

func Igen 

func Igen(n *Node, a *Node, res *Node)

Igen computes the address &n, stores it in a register r, and rewrites a to refer to *r. The chosen r may be the stack pointer, it may be borrowed from res, or it may be a newly allocated register. The caller must call Regfree(a) to free r when the address is no longer needed. The generated code ensures that &n is not nil.

func Import 

func Import(in *obj.Biobuf)

Import populates importpkg from the serialized package data.

func Is64 

func Is64(t *Type) bool

Is this a 64-bit type?

func Isconst 

func Isconst(n *Node, ct Ctype) bool

func Isfat 

func Isfat(t *Type) bool

func Isfixedarray 

func Isfixedarray(t *Type) bool

func Isinter 

func Isinter(t *Type) bool

func Ismem 

func Ismem(n *Node) bool

Is this node a memory operand?

func Isslice 

func Isslice(t *Type) bool

func Istype 

func Istype(t *Type, et EType) bool

func Jconv 

func Jconv(n *Node, flag int) string

Fmt "%J": Node details.

func LOAD 

func LOAD(r *Reg, z int) uint64

func Linksym 

func Linksym(s *Sym) *obj.LSym

func Main 

func Main()

func Mfree 

func Mfree(n *Node)

func Mgen 

func Mgen(n *Node, n1 *Node, rg *Node)

func Mpcmpfixfix 

func Mpcmpfixfix(a, b *Mpint) int

func Mpgetfix 

func Mpgetfix(a *Mpint) int64

func Mpmovecfix 

func Mpmovecfix(a *Mpint, c int64)

func Mpmovecflt 

func Mpmovecflt(a *Mpflt, c float64)

func Mpmovefixflt 

func Mpmovefixflt(a *Mpflt, b *Mpint)

func Mpshiftfix 

func Mpshiftfix(a *Mpint, s int)

shift left by s (or right by -s)

func Naddr 

func Naddr(a *obj.Addr, n *Node)

Naddr rewrites a to refer to n. It assumes that a is zeroed on entry.

func Nconv 

func Nconv(n *Node, flag int) string

Fmt '%N': Nodes. Flags: 'l' suffix with "(type %T)" where possible 

'+h' in debug mode, don't recurse, no multiline output

func Noconv 

func Noconv(t1 *Type, t2 *Type) bool

Is a conversion between t1 and t2 a no-op?

func Nodconst 

func Nodconst(n *Node, t *Type, v int64)

func Nodindreg 

func Nodindreg(n *Node, t *Type, r int)

func Nodreg 

func Nodreg(n *Node, t *Type, r int)

func Noreturn 

func Noreturn(p *obj.Prog) bool

p is a call instruction. Does the call fail to return?

func Oconv 

func Oconv(o int, flag int) string

Fmt "%O": Node opcodes

func Patch 

func Patch(p *obj.Prog, to *obj.Prog)

func Prog 

func Prog(as int) *obj.Prog

func Regalloc 

func Regalloc(n *Node, t *Type, o *Node)

allocate register of type t, leave in n. if o != N, o may be reusable register. caller must Regfree(n).

func Regdump 

func Regdump()

func Regfree 

func Regfree(n *Node)

func Reginuse 

func Reginuse(r int) bool

Reginuse reports whether r is in use.

func Regrealloc 

func Regrealloc(n *Node)

Regrealloc(n) undoes the effect of Regfree(n), so that a register can be given up but then reclaimed.

func Rnd 

func Rnd(o int64, r int64) int64

func STORE 

func STORE(r *Reg, z int) uint64

func Samereg 

func Samereg(a *Node, b *Node) bool

func Sconv 

func Sconv(s *Sym, flag int) string

Fmt "%S": syms Flags: "%hS" suppresses qualifying with package

func SetReg 

func SetReg(r, v int)

func Setmaxarg 

func Setmaxarg(t *Type, extra int32)

func Smagic 

func Smagic(m *Magic)

magic number for signed division see hacker's delight chapter 10

func Smallintconst 

func Smallintconst(n *Node) bool

func Tconv 

func Tconv(t *Type, flag int) string

Fmt "%T": types. Flags: 'l' print definition, not name 

'h' omit 'func' and receiver from function types, short type names
'u' package name, not prefix (FTypeId mode, sticky)

func Tempname 

func Tempname(nn *Node, t *Type)

make a new off the books

func Umagic 

func Umagic(m *Magic)

magic number for unsigned division see hacker's delight chapter 10

func Vconv 

func Vconv(v Val, flag int) string

Fmt "%V": Values

func Warn 

func Warn(fmt_ string, args ...interface{})

func Warnl 

func Warnl(line int, fmt_ string, args ...interface{})

func Yyerror 

func Yyerror(format string, args ...interface{})

Types

type Arch 

type Arch struct {
	Thechar      int
	Thestring    string
	Thelinkarch  *obj.LinkArch
	Typedefs     []Typedef
	REGSP        int
	REGCTXT      int
	REGCALLX     int // BX
	REGCALLX2    int // AX
	REGRETURN    int // AX
	REGMIN       int
	REGMAX       int
	REGZERO      int // architectural zero register, if available
	FREGMIN      int
	FREGMAX      int
	MAXWIDTH     int64
	ReservedRegs []int

	AddIndex     func(*Node, int64, *Node) bool // optional
	Betypeinit   func()
	Bgen_float   func(*Node, bool, int, *obj.Prog) // optional
	Cgen64       func(*Node, *Node)                // only on 32-bit systems
	Cgenindex    func(*Node, *Node, bool) *obj.Prog
	Cgen_bmul    func(Op, *Node, *Node, *Node) bool
	Cgen_float   func(*Node, *Node) // optional
	Cgen_hmul    func(*Node, *Node, *Node)
	Cgen_shift   func(Op, bool, *Node, *Node, *Node)
	Clearfat     func(*Node)
	Cmp64        func(*Node, *Node, Op, int, *obj.Prog) // only on 32-bit systems
	Defframe     func(*obj.Prog)
	Dodiv        func(Op, *Node, *Node, *Node)
	Excise       func(*Flow)
	Expandchecks func(*obj.Prog)
	Getg         func(*Node)
	Gins         func(int, *Node, *Node) *obj.Prog

	// Ginscmp generates code comparing n1 to n2 and jumping away if op is satisfied.
	// The returned prog should be Patch'ed with the jump target.
	// If op is not satisfied, code falls through to the next emitted instruction.
	// Likely is the branch prediction hint: +1 for likely, -1 for unlikely, 0 for no opinion.
	//
	// Ginscmp must be able to handle all kinds of arguments for n1 and n2,
	// not just simple registers, although it can assume that there are no
	// function calls needed during the evaluation, and on 32-bit systems
	// the values are guaranteed not to be 64-bit values, so no in-memory
	// temporaries are necessary.
	Ginscmp func(op Op, t *Type, n1, n2 *Node, likely int) *obj.Prog

	// Ginsboolval inserts instructions to convert the result
	// of a just-completed comparison to a boolean value.
	// The first argument is the conditional jump instruction
	// corresponding to the desired value.
	// The second argument is the destination.
	// If not present, Ginsboolval will be emulated with jumps.
	Ginsboolval func(int, *Node)

	Ginscon      func(int, int64, *Node)
	Ginsnop      func()
	Gmove        func(*Node, *Node)
	Igenindex    func(*Node, *Node, bool) *obj.Prog
	Linkarchinit func()
	Peep         func(*obj.Prog)
	Proginfo     func(*obj.Prog) // fills in Prog.Info
	Regtyp       func(*obj.Addr) bool
	Sameaddr     func(*obj.Addr, *obj.Addr) bool
	Smallindir   func(*obj.Addr, *obj.Addr) bool
	Stackaddr    func(*obj.Addr) bool
	Blockcopy    func(*Node, *Node, int64, int64, int64)
	Sudoaddable  func(int, *Node, *obj.Addr) bool
	Sudoclean    func()
	Excludedregs func() uint64
	RtoB         func(int) uint64
	FtoB         func(int) uint64
	BtoR         func(uint64) int
	BtoF         func(uint64) int
	Optoas       func(Op, *Type) int
	Doregbits    func(int) uint64
	Regnames     func(*int) []string
	Use387       bool // should 8g use 387 FP instructions instead of sse2.
}
var Thearch Arch

type BasicBlock 

type BasicBlock struct {
	// contains filtered or unexported fields
}

An ordinary basic block.

Instructions are threaded together in a doubly-linked list. To iterate in program order follow the link pointer from the first node and stop after the last node has been visited 

for(p = bb->first;; p = p->link) {
  ...
  if(p == bb->last)
    break;
}

To iterate in reverse program order by following the opt pointer from the last node 

for(p = bb->last; p != nil; p = p->opt) {
  ...
}

type Bits 

type Bits struct {
	// contains filtered or unexported fields
}

Bits represents a set of Vars, stored as a bit set of var numbers (the index in vars, or equivalently v.id).

func (Bits) String 

func (bits Bits) String() string

String returns a space-separated list of the variables represented by bits.

type Bvec 

type Bvec struct {
	// contains filtered or unexported fields
}

A Bvec is a bit vector.

type Class 

type Class uint8

The Class of a variable/function describes the "storage class" of a variable or function. During parsing, storage classes are called declaration contexts. 

const (
	Pxxx      Class = iota
	PEXTERN         // global variable
	PAUTO           // local variables
	PPARAM          // input arguments
	PPARAMOUT       // output results
	PPARAMREF       // closure variable reference
	PFUNC           // global function

	PDISCARD // discard during parse of duplicate import

	PHEAP = 1 << 7 // an extra bit to identify an escaped variable
)

type Ctype 

type Ctype int8

Ctype describes the constant kind of an "ideal" (untyped) constant. 

const (
	CTxxx Ctype = iota

	CTINT
	CTRUNE
	CTFLT
	CTCPLX
	CTSTR
	CTBOOL
	CTNIL
)

type Dlist 

type Dlist struct {
	// contains filtered or unexported fields
}

type EType 

type EType uint8
var Tptr EType // either TPTR32 or TPTR64

func Simsimtype 

func Simsimtype(t *Type) EType

even simpler simtype; get rid of ptr, bool. assuming that the front end has rejected all the invalid conversions (like ptr -> bool)

type Error 

type Error struct {
	// contains filtered or unexported fields
}

type EscState 

type EscState struct {
	// contains filtered or unexported fields
}

type Flow 

type Flow struct {
	Prog   *obj.Prog // actual instruction
	P1     *Flow     // predecessors of this instruction: p1,
	P2     *Flow     // and then p2 linked though p2link.
	P2link *Flow
	S1     *Flow // successors of this instruction (at most two: s1 and s2).
	S2     *Flow
	Link   *Flow // next instruction in function code

	Active int32 // usable by client

	Id     int32  // sequence number in flow graph
	Rpo    int32  // reverse post ordering
	Loop   uint16 // x5 for every loop
	Refset bool   // diagnostic generated

	Data interface{} // for use by client
}

func Uniqp 

func Uniqp(r *Flow) *Flow

func Uniqs 

func Uniqs(r *Flow) *Flow

type Func 

type Func struct {
	Shortname  *Node
	Enter      *NodeList
	Exit       *NodeList
	Cvars      *NodeList // closure params
	Dcl        *NodeList // autodcl for this func/closure
	Inldcl     *NodeList // copy of dcl for use in inlining
	Closgen    int
	Outerfunc  *Node
	Fieldtrack []*Type
	Outer      *Node // outer func for closure
	Ntype      *Node // signature
	Top        int   // top context (Ecall, Eproc, etc)
	Closure    *Node // OCLOSURE <-> ODCLFUNC
	FCurfn     *Node
	Nname      *Node

	Inl     *NodeList // copy of the body for use in inlining
	InlCost int32
	Depth   int32

	Endlineno int32

	Norace         bool // func must not have race detector annotations
	Nosplit        bool // func should not execute on separate stack
	Noinline       bool // func should not be inlined
	Nowritebarrier bool // emit compiler error instead of write barrier
	Dupok          bool // duplicate definitions ok
	Wrapper        bool // is method wrapper
	Needctxt       bool // function uses context register (has closure variables)
	Systemstack    bool // must run on system stack
}

Func holds Node fields used only with function-like nodes.

type GCProg 

type GCProg struct {
	// contains filtered or unexported fields
}

type Graph 

type Graph struct {
	Start *Flow
	Num   int

	// After calling flowrpo, rpo lists the flow nodes in reverse postorder,
	// and each non-dead Flow node f has g->rpo[f->rpo] == f.
	Rpo []*Flow
}

func Flowstart 

func Flowstart(firstp *obj.Prog, newData func() interface{}) *Graph

type Idir 

type Idir struct {
	// contains filtered or unexported fields
}

type InitEntry 

type InitEntry struct {
	Xoffset int64 // struct, array only
	Expr    *Node // bytes of run-time computed expressions
}

type InitPlan 

type InitPlan struct {
	Lit  int64
	Zero int64
	Expr int64
	E    []InitEntry
}

type Io 

type Io struct {
	// contains filtered or unexported fields
}

type Iter 

type Iter struct {
	Done  int
	Tfunc *Type
	T     *Type
}

type Label 

type Label struct {
	Sym  *Sym
	Def  *Node
	Use  []*Node
	Link *Label

	// for use during gen
	Gotopc   *obj.Prog // pointer to unresolved gotos
	Labelpc  *obj.Prog // pointer to code
	Breakpc  *obj.Prog // pointer to code
	Continpc *obj.Prog // pointer to code

	Used bool
}

type Level 

type Level struct {
	// contains filtered or unexported fields
}

A Level encodes the reference state and context applied to (stack, heap) allocated memory.

value is the overall sum of *(1) and &(-1) operations encountered along a path from a destination (sink, return value) to a source (allocation, parameter).

suffixValue is the maximum-copy-started-suffix-level applied to a sink. For example: sink = x.left.left --> level=2, x is dereferenced twice and does not escape to sink. sink = &Node{x} --> level=-1, x is accessible from sink via one "address of" sink = &Node{&Node{x}} --> level=-2, x is accessible from sink via two "address of" sink = &Node{&Node{x.left}} --> level=-1, but x is NOT accessible from sink because it was indirected and then copied. (The copy operations are sometimes implicit in the source code; in this case, value of x.left was copied into a field of a newly allocated Node)

There's one of these for each Node, and the integer values rarely exceed even what can be stored in 4 bits, never mind 8.

type Liveness 

type Liveness struct {
	// contains filtered or unexported fields
}

A collection of global state used by liveness analysis.

type Loophack 

type Loophack struct {
	// contains filtered or unexported fields
}

type Magic 

type Magic struct {
	W   int // input for both - width
	S   int // output for both - shift
	Bad int // output for both - unexpected failure

	// magic multiplier for signed literal divisors
	Sd int64 // input - literal divisor
	Sm int64 // output - multiplier

	// magic multiplier for unsigned literal divisors
	Ud uint64 // input - literal divisor
	Um uint64 // output - multiplier
	Ua int    // output - adder
}

argument passing to/from smagic and umagic

type Mpcplx 

type Mpcplx struct {
	Real Mpflt
	Imag Mpflt
}

Mpcplx represents a complex constant.

type Mpflt 

type Mpflt struct {
	Val big.Float
}

Mpflt represents a floating-point constant.

func (*Mpflt) String 

func (f *Mpflt) String() string

type Mpint 

type Mpint struct {
	Val  big.Int
	Ovf  bool // set if Val overflowed compiler limit (sticky)
	Rune bool // set if syntax indicates default type rune
}

Mpint represents an integer constant.

func (*Mpint) String 

func (x *Mpint) String() string

type Name 

type Name struct {
	Pack      *Node // real package for import . names
	Pkg       *Pkg  // pkg for OPACK nodes
	Heapaddr  *Node // temp holding heap address of param
	Inlvar    *Node // ONAME substitute while inlining
	Defn      *Node // initializing assignment
	Curfn     *Node // function for local variables
	Param     *Param
	Decldepth int32 // declaration loop depth, increased for every loop or label
	Vargen    int32 // unique name for ONAME within a function.  Function outputs are numbered starting at one.
	Iota      int32 // value if this name is iota
	Funcdepth int32
	Method    bool // OCALLMETH name
	Readonly  bool
	Captured  bool // is the variable captured by a closure
	Byval     bool // is the variable captured by value or by reference
	Needzero  bool // if it contains pointers, needs to be zeroed on function entry
}

Name holds Node fields used only by named nodes (ONAME, OPACK, some OLITERAL).

type NilVal 

type NilVal struct{}

type Node 

type Node struct {
	// Tree structure.
	// Generic recursive walks should follow these fields.
	Left  *Node
	Right *Node
	Ninit *NodeList
	Nbody *NodeList
	List  *NodeList
	Rlist *NodeList

	// most nodes
	Type *Type
	Orig *Node // original form, for printing, and tracking copies of ONAMEs

	// func
	Func *Func

	// ONAME
	Name *Name

	Sym *Sym        // various
	E   interface{} // Opt or Val, see methods below

	Xoffset int64

	Lineno int32

	// OREGISTER, OINDREG
	Reg int16

	Esc uint16 // EscXXX

	Op          Op
	Nointerface bool
	Ullman      uint8 // sethi/ullman number
	Addable     bool  // addressable
	Etype       EType // op for OASOP, etype for OTYPE, exclam for export, 6g saved reg
	Bounded     bool  // bounds check unnecessary
	Class       Class // PPARAM, PAUTO, PEXTERN, etc
	Embedded    uint8 // ODCLFIELD embedded type
	Colas       bool  // OAS resulting from :=
	Diag        uint8 // already printed error about this
	Noescape    bool  // func arguments do not escape; TODO(rsc): move Noescape to Func struct (see CL 7360)
	Walkdef     uint8
	Typecheck   uint8
	Local       bool
	Dodata      uint8
	Initorder   uint8
	Used        bool
	Isddd       bool // is the argument variadic
	Implicit    bool
	Addrtaken   bool // address taken, even if not moved to heap
	Assigned    bool // is the variable ever assigned to
	Likely      int8 // likeliness of if statement
	Hasbreak    bool // has break statement
	// contains filtered or unexported fields
}

A Node is a single node in the syntax tree. Actually the syntax tree is a syntax DAG, because there is only one node with Op=ONAME for a given instance of a variable x. The same is true for Op=OTYPE and Op=OLITERAL. 

var Curfn *Node
var Deferproc *Node
var Deferreturn *Node
var Newproc *Node
var Panicindex *Node

func CgenTemp 

func CgenTemp(n *Node) *Node

CgenTemp creates a temporary node, assigns n to it, and returns it.

func Nod 

func Nod(op Op, nleft *Node, nright *Node) *Node

func Nodbool 

func Nodbool(b bool) *Node

func Nodintconst 

func Nodintconst(v int64) *Node

func Sysfunc 

func Sysfunc(name string) *Node

func (*Node) Bool 

func (n *Node) Bool() bool

Bool returns n as an bool. n must be an boolean constant.

func (*Node) Convconst 

func (n *Node) Convconst(con *Node, t *Type)

Convconst converts constant node n to type t and places the result in con.

func (*Node) Int 

func (n *Node) Int() int64

Int returns n as an int. n must be an integer constant.

func (*Node) IntLiteral 

func (n *Node) IntLiteral() (x int64, ok bool)

IntLiteral returns the Node's literal value as an interger.

func (*Node) Line 

func (n *Node) Line() string

func (*Node) Opt 

func (n *Node) Opt() interface{}

Opt returns the optimizer data for the node.

func (*Node) SetBigInt 

func (n *Node) SetBigInt(x *big.Int)

SetBigInt sets n's value to x. n must be an integer constant.

func (*Node) SetInt 

func (n *Node) SetInt(i int64)

SetInt sets n's value to i. n must be an integer constant.

func (*Node) SetOpt 

func (n *Node) SetOpt(x interface{})

SetOpt sets the optimizer data for the node, which must not have been used with SetVal. SetOpt(nil) is ignored for Vals to simplify call sites that are clearing Opts.

func (*Node) SetVal 

func (n *Node) SetVal(v Val)

SetVal sets the Val for the node, which must not have been used with SetOpt.

func (*Node) String 

func (n *Node) String() string

func (*Node) Val 

func (n *Node) Val() Val

Val returns the Val for the node.

type NodeEscState 

type NodeEscState struct {
	Curfn        *Node
	Escflowsrc   *NodeList // flow(this, src)
	Escretval    *NodeList // on OCALLxxx, list of dummy return values
	Escloopdepth int32     // -1: global, 0: return variables, 1:function top level, increased inside function for every loop or label to mark scopes
	Esclevel     Level
	Walkgen      uint32
}

type NodeList 

type NodeList struct {
	N    *Node
	Next *NodeList
	End  *NodeList
}

A NodeList is a linked list of nodes. TODO(rsc): Some uses of NodeList should be made into slices. The remaining ones probably just need a simple linked list, not one with concatenation support.

func (*NodeList) String 

func (l *NodeList) String() string

type Op 

type Op uint8

func Brcom 

func Brcom(op Op) Op

Brcom returns !(op). For example, Brcom(==) is !=.

func Brrev 

func Brrev(op Op) Op

Brrev returns reverse(op). For example, Brrev(<) is >.

type OptStats 

type OptStats struct {
	Ncvtreg int32
	Nspill  int32
	Nreload int32
	Ndelmov int32
	Nvar    int32
	Naddr   int32
}
var Ostats OptStats

type Order 

type Order struct {
	// contains filtered or unexported fields
}

Order holds state during the ordering process.

type Param 

type Param struct {
	Ntype *Node

	// ONAME func param with PHEAP
	Outerexpr  *Node // expression copied into closure for variable
	Stackparam *Node // OPARAM node referring to stack copy of param

	// ONAME PPARAM
	Field *Type // TFIELD in arg struct

	// ONAME closure param with PPARAMREF
	Outer   *Node // outer PPARAMREF in nested closure
	Closure *Node // ONAME/PHEAP <-> ONAME/PPARAMREF
}

type Pkg 

type Pkg struct {
	Name     string // package name
	Path     string // string literal used in import statement
	Pathsym  *Sym
	Prefix   string // escaped path for use in symbol table
	Imported bool   // export data of this package was parsed
	Exported bool   // import line written in export data
	Direct   bool   // imported directly
	Safe     bool   // whether the package is marked as safe
	Syms     map[string]*Sym
}
var Runtimepkg *Pkg // package runtime

func (*Pkg) Lookup 

func (pkg *Pkg) Lookup(name string) *Sym

func (*Pkg) LookupBytes 

func (pkg *Pkg) LookupBytes(name []byte) *Sym

type Reg 

type Reg struct {
	// contains filtered or unexported fields
}

A Reg is a wrapper around a single Prog (one instruction) that holds register optimization information while the optimizer runs. r->prog is the instruction.

type Rgn 

type Rgn struct {
	// contains filtered or unexported fields
}

A Rgn represents a single regopt variable over a region of code where a register could potentially be dedicated to that variable. The code encompassed by a Rgn is defined by the flow graph, starting at enter, flood-filling forward while varno is refahead and backward while varno is refbehind, and following branches. A single variable may be represented by multiple disjoint Rgns and each Rgn may choose a different register for that variable. Registers are allocated to regions greedily in order of descending cost.

type Sig 

type Sig struct {
	// contains filtered or unexported fields
}

type Sym 

type Sym struct {
	Lexical   uint16
	Flags     uint8
	Link      *Sym
	Uniqgen   uint32
	Importdef *Pkg   // where imported definition was found
	Linkname  string // link name

	// saved and restored by dcopy
	Pkg        *Pkg
	Name       string // variable name
	Def        *Node  // definition: ONAME OTYPE OPACK or OLITERAL
	Label      *Label // corresponding label (ephemeral)
	Block      int32  // blocknumber to catch redeclaration
	Lastlineno int32  // last declaration for diagnostic
	Origpkg    *Pkg   // original package for . import
	Lsym       *obj.LSym
	Fsym       *Sym // funcsym
}

func Lookup 

func Lookup(name string) *Sym

func LookupBytes 

func LookupBytes(name []byte) *Sym

func Lookupf 

func Lookupf(format string, a ...interface{}) *Sym

func Pkglookup 

func Pkglookup(name string, pkg *Pkg) *Sym

func (*Sym) String 

func (s *Sym) String() string
type Symlink struct {
	// contains filtered or unexported fields
}

code to help generate trampoline functions for methods on embedded subtypes. these are approx the same as the corresponding adddot routines except that they expect to be called with unique tasks and they return the actual methods.

type TempVar 

type TempVar struct {
	// contains filtered or unexported fields
}

type Type 

type Type struct {
	Etype       EType
	Nointerface bool
	Noalg       bool
	Chan        uint8
	Trecur      uint8 // to detect loops
	Printed     bool
	Embedded    uint8 // TFIELD embedded type
	Funarg      bool  // on TSTRUCT and TFIELD
	Copyany     bool
	Local       bool // created in this file
	Deferwidth  bool
	Broke       bool // broken type definition.
	Isddd       bool // TFIELD is ... argument
	Align       uint8
	Haspointers uint8 // 0 unknown, 1 no, 2 yes

	Nod    *Node // canonical OTYPE node
	Orig   *Type // original type (type literal or predefined type)
	Lineno int

	// TFUNC
	Thistuple int
	Outtuple  int
	Intuple   int
	Outnamed  bool

	Method  *Type
	Xmethod *Type

	Sym    *Sym
	Vargen int32 // unique name for OTYPE/ONAME

	Nname  *Node
	Argwid int64

	// most nodes
	Type  *Type // actual type for TFIELD, element type for TARRAY, TCHAN, TMAP, TPTRxx
	Width int64 // offset in TFIELD, width in all others

	// TFIELD
	Down  *Type   // next struct field, also key type in TMAP
	Outer *Type   // outer struct
	Note  *string // literal string annotation

	// TARRAY
	Bound int64 // negative is dynamic array

	// TMAP
	Bucket *Type // internal type representing a hash bucket
	Hmap   *Type // internal type representing a Hmap (map header object)
	Hiter  *Type // internal type representing hash iterator state
	Map    *Type // link from the above 3 internal types back to the map type.

	Maplineno   int32 // first use of TFORW as map key
	Embedlineno int32 // first use of TFORW as embedded type

	// for TFORW, where to copy the eventual value to
	Copyto []*Node

	Lastfn *Node // for usefield
}

func Getoutarg 

func Getoutarg(t *Type) **Type

func Ptrto 

func Ptrto(t *Type) *Type

Ptrto returns the Type *t. The returned struct must not be modified.

func Structfirst 

func Structfirst(s *Iter, nn **Type) *Type

iterator to walk a structure declaration

func (*Type) String 

func (t *Type) String() string

type TypeList 

type TypeList struct {
	// contains filtered or unexported fields
}

when a type's width should be known, we call checkwidth to compute it. during a declaration like 

type T *struct { next T }

it is necessary to defer the calculation of the struct width until after T has been initialized to be a pointer to that struct. similarly, during import processing structs may be used before their definition. in those situations, calling defercheckwidth() stops width calculations until resumecheckwidth() is called, at which point all the checkwidths that were deferred are executed. dowidth should only be called when the type's size is needed immediately. checkwidth makes sure the size is evaluated eventually.

type TypePairList 

type TypePairList struct {
	// contains filtered or unexported fields
}

type Typedef 

type Typedef struct {
	Name   string
	Etype  EType
	Sameas EType
}

type Val 

type Val struct {
	// U contains one of:
	// bool     bool when n.ValCtype() == CTBOOL
	// *Mpint   int when n.ValCtype() == CTINT, rune when n.ValCtype() == CTRUNE
	// *Mpflt   float when n.ValCtype() == CTFLT
	// *Mpcplx  pair of floats when n.ValCtype() == CTCPLX
	// string   string when n.ValCtype() == CTSTR
	// *Nilval  when n.ValCtype() == CTNIL
	U interface{}
}

func (Val) Ctype 

func (v Val) Ctype() Ctype

type Var 

type Var struct {
	// contains filtered or unexported fields
}

A Var represents a single variable that may be stored in a register. That variable may itself correspond to a hardware register, to represent the use of registers in the unoptimized instruction stream.

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