gc

package
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Published: Jul 3, 2016 License: BSD-3-Clause, MIT Imports: 28 Imported by: 0

Documentation

Index

Constants

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const (
	WORDBITS  = 32
	WORDMASK  = WORDBITS - 1
	WORDSHIFT = 5
)
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const (
	EscFuncUnknown = 0 + iota
	EscFuncPlanned
	EscFuncStarted
	EscFuncTagged
)
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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.

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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 Nodes	Nodes
		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 (
	UINF            = 100
	BADWIDTH        = -1000000000
	MaxStackVarSize = 10 * 1024 * 1024
)
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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.
	// Originally for understanding ADC, RCR, and so on, but now also
	// tracks set, use, and kill of the zero and overflow bits as well.
	// TODO rename to {Set,Use,Kill}Flags
	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
)
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const (
	EOF = -1
	BOM = 0xFEFF
)
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const (

	// names and literals
	LNAME = utf8.RuneSelf + iota
	LLITERAL

	// operator-based operations
	LOPER
	LASOP
	LINCOP

	// miscellaneous
	LCOLAS
	LCOMM
	LDDD

	// keywords
	LBREAK
	LCASE
	LCHAN
	LCONST
	LCONTINUE
	LDEFAULT
	LDEFER
	LELSE
	LFALL
	LFOR
	LFUNC
	LGO
	LGOTO
	LIF
	LIMPORT
	LINTERFACE
	LMAP
	LPACKAGE
	LRANGE
	LRETURN
	LSELECT
	LSTRUCT
	LSWITCH
	LTYPE
	LVAR

	LIGNORE
)
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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 (
	UNVISITED = 0
	VISITED   = 1
)
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const (
	H0 = 2166136261
	Hp = 16777619
)

FNV-1 hash function constants.

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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
)
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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 (
	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          // +{List} (string addition, list elements are strings)
	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.Sym (Left is of struct type)
	ODOTPTR   // Left.Sym (Left is of pointer to struct type)
	ODOTMETH  // Left.Sym (Left is non-interface, Right is method name)
	ODOTINTER // Left.Sym (Left is interface, Right is method name)
	OXDOT     // Left.Sym (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)

	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
	OVARLIVE    // variable is alive

	// 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 (
	Txxx = iota

	TINT8
	TUINT8
	TINT16
	TUINT16
	TINT32
	TUINT32
	TINT64
	TUINT64
	TINT
	TUINT
	TUINTPTR

	TCOMPLEX64
	TCOMPLEX128

	TFLOAT32
	TFLOAT64

	TBOOL

	TPTR32
	TPTR64

	TFUNC
	TSLICE
	TARRAY
	TSTRUCT
	TCHAN
	TMAP
	TINTER
	TFORW
	TANY
	TSTRING
	TUNSAFEPTR

	// pseudo-types for literals
	TIDEAL
	TNIL
	TBLANK

	// pseudo-types for frame layout
	TFUNCARGS
	TCHANARGS
	TINTERMETH

	// pseudo-types for import/export
	TDDDFIELD // wrapper: contained type is a ... field

	NTYPE
)
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const (
	Etop      = 1 << iota // evaluated at statement level
	Erv                   // evaluated in value context
	Etype                 // evaluated in type context
	Ecall                 // call-only expressions are ok
	Efnstruct             // multivalue function returns are ok
	Easgn                 // assigning to expression
	Ecomplit              // type in composite literal
)
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const (
	ArhdrSize = 60
)

architecture-independent object file output

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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.

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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.

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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 NOTALOOPDEPTH = -1

Variables

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var (
	Isint     [NTYPE]bool
	Isfloat   [NTYPE]bool
	Iscomplex [NTYPE]bool
)
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var (
	Debug_append  int
	Debug_closure int
	Debug_panic   int
	Debug_slice   int
	Debug_wb      int
)
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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)
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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 // len(funcstack) during parsing, but then forced to be the same later during compilation
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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

Types stores pointers to predeclared named types.

It also stores pointers to several special types:

  • Types[TANY] is the placeholder "any" type recognized by substArgTypes.
  • Types[TBLANK] represents the blank variable's type.
  • Types[TIDEAL] represents untyped numeric constants.
  • Types[TNIL] represents the predeclared "nil" value's type.
  • Types[TUNSAFEPTR] is package unsafe's Pointer type.
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var Widthint int
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var Widthptr int
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var Widthreg int

Functions

func AddAux

func AddAux(a *obj.Addr, v *ssa.Value)

AddAux adds the offset in the aux fields (AuxInt and Aux) of v to a.

func AddAux2

func AddAux2(a *obj.Addr, v *ssa.Value, offset int64)

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 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 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 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 Eqtype

func Eqtype(t1, t2 *Type) bool

Eqtype reports whether 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 Fatalf

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

func Fixlargeoffset

func Fixlargeoffset(n *Node)

func Fldconv

func Fldconv(f *Field, flag FmtFlag) string

func Flowend

func Flowend(graph *Graph)

func Flusherrors

func Flusherrors()

func Gbranch

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

func Genlist

func Genlist(l Nodes)

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 Gvarkill

func Gvarkill(n *Node)

func Gvarlive

func Gvarlive(n *Node)

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 *bufio.Reader)

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 Ismem

func Ismem(n *Node) bool

Is this node a memory operand?

func IterFields

func IterFields(t *Type) (*Field, Iter)

IterFields returns the first field or method in struct or interface type t and an Iter value to continue iterating across the rest.

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 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 FmtFlag) 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 Patch

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

func Prog

func Prog(as obj.As) *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 SSAGenFPJump

func SSAGenFPJump(s *SSAGenState, b, next *ssa.Block, jumps *[2][2]FloatingEQNEJump)

func SSARegNum

func SSARegNum(v *ssa.Value) int16

SSARegNum returns the register (in cmd/internal/obj numbering) to which v has been allocated. Panics if v is not assigned to a register. TODO: Make this panic again once it stops happening routinely.

func STORE

func STORE(r *Reg, z int) uint64

func Samereg

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

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 FmtFlag) 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 Warn

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

func Warnl

func Warnl(line int32, fmt_ string, args ...interface{})

func Yyerror

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

Types

type AlgKind

type AlgKind int

AlgKind describes the kind of algorithms used for comparing and hashing a Type.

const (
	// These values are known by runtime.
	ANOEQ AlgKind = iota
	AMEM0
	AMEM8
	AMEM16
	AMEM32
	AMEM64
	AMEM128
	ASTRING
	AINTER
	ANILINTER
	AFLOAT32
	AFLOAT64
	ACPLX64
	ACPLX128

	// Type can be compared/hashed as regular memory.
	AMEM AlgKind = 100

	// Type needs special comparison/hashing functions.
	ASPECIAL AlgKind = -1
)

type Arch

type Arch struct {
	LinkArch *obj.LinkArch

	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)
	RightShiftWithCarry func(*Node, uint, *Node)  // only on systems without RROTC instruction
	AddSetCarry         func(*Node, *Node, *Node) // only on systems when ADD does not update carry flag
	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(obj.As, *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(obj.As, *Node)

	Ginscon      func(obj.As, int64, *Node)
	Ginsnop      func()
	Gmove        func(*Node, *Node)
	Igenindex    func(*Node, *Node, bool) *obj.Prog
	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(obj.As, *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) obj.As
	Doregbits    func(int) uint64
	Regnames     func(*int) []string
	Use387       bool // should 8g use 387 FP instructions instead of sse2.

	// SSARegToReg maps ssa register numbers to obj register numbers.
	SSARegToReg []int16

	// SSAMarkMoves marks any MOVXconst ops that need to avoid clobbering flags.
	SSAMarkMoves func(*SSAGenState, *ssa.Block)

	// SSAGenValue emits Prog(s) for the Value.
	SSAGenValue func(*SSAGenState, *ssa.Value)

	// SSAGenBlock emits end-of-block Progs. SSAGenValue should be called
	// for all values in the block before SSAGenBlock.
	SSAGenBlock func(s *SSAGenState, b, next *ssa.Block)
}
var Thearch Arch

type ArrayType

type ArrayType struct {
	Elem        *Type // element type
	Bound       int64 // number of elements; <0 if unknown yet
	Haspointers uint8 // 0 unknown, 1 no, 2 yes
}

ArrayType contains Type fields specific to array types.

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 Branch

type Branch struct {
	P *obj.Prog  // branch instruction
	B *ssa.Block // target
}

Branch is an unresolved branch.

type ChanArgsType

type ChanArgsType struct {
	T *Type // reference to a chan type whose elements need a width check
}

ChanArgsType contains Type fields specific to TCHANARGS types.

type ChanDir

type ChanDir uint8

ChanDir is whether a channel can send, receive, or both.

const (
	// types of channel
	// must match ../../../../reflect/type.go:/ChanDir
	Crecv ChanDir = 1 << 0
	Csend ChanDir = 1 << 1
	Cboth ChanDir = Crecv | Csend
)

func (ChanDir) CanRecv

func (c ChanDir) CanRecv() bool

func (ChanDir) CanSend

func (c ChanDir) CanSend() bool

type ChanType

type ChanType struct {
	Elem *Type   // element type
	Dir  ChanDir // channel direction
}

ChanType contains Type fields specific to channel types.

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
	PAUTOHEAP       // local variable or parameter moved to heap
	PPARAM          // input arguments
	PPARAMOUT       // output results
	PFUNC           // global function

	PDISCARD // discard during parse of duplicate import
)

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 DDDFieldType

type DDDFieldType struct {
	T *Type // reference to a slice type for ... args
}

DDDFieldType contains Type fields specific to TDDDFIELD types.

type Dlist

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

A Dlist stores a pointer to a TFIELD Type embedded within a TSTRUCT or TINTER Type.

type EType

type EType uint8

EType describes a kind of type.

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)

func (EType) String

func (et EType) String() string

type Error

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

type EscState

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

type EscStep

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

An EscStep documents one step in the path from memory that is heap allocated to the (alleged) reason for the heap allocation.

type Field

type Field struct {
	Nointerface bool
	Embedded    uint8 // embedded field
	Funarg      Funarg
	Broke       bool // broken field definition
	Isddd       bool // field is ... argument

	Sym   *Sym
	Nname *Node

	Type *Type // field type

	// Offset in bytes of this field or method within its enclosing struct
	// or interface Type.
	Offset int64

	Note string // literal string annotation
}

A Field represents a field in a struct or a method in an interface or associated with a named type.

func (*Field) Copy

func (f *Field) Copy() *Field

func (*Field) End

func (f *Field) End() int64

End returns the offset of the first byte immediately after this field.

type Fields

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

Fields is a pointer to a slice of *Field. This saves space in Types that do not have fields or methods compared to a simple slice of *Field.

func (*Fields) Append

func (f *Fields) Append(s ...*Field)

Append appends entries to f.

func (*Fields) Index

func (f *Fields) Index(i int) *Field

Index returns the i'th element of Fields. It panics if f does not have at least i+1 elements.

func (*Fields) Iter

func (fs *Fields) Iter() (*Field, Iter)

Iter returns the first field in fs and an Iter value to continue iterating across its successor fields. Deprecated: New code should use Slice instead.

func (*Fields) Len

func (f *Fields) Len() int

Len returns the number of entries in f.

func (*Fields) Set

func (f *Fields) Set(s []*Field)

Set sets f to a slice. This takes ownership of the slice.

func (*Fields) Slice

func (f *Fields) Slice() []*Field

Slice returns the entries in f as a slice. Changes to the slice entries will be reflected in f.

type FloatingEQNEJump

type FloatingEQNEJump struct {
	Jump  obj.As
	Index int
}

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 FmtFlag

type FmtFlag int

A FmtFlag value is a set of flags (or 0). They control how the Xconv functions format their values. See the respective function's documentation for details.

const (
	FmtWidth    FmtFlag = 1 << iota
	FmtLeft             // "-"
	FmtSharp            // "#"
	FmtSign             // "+"
	FmtUnsigned         // "u"
	FmtShort            // "h"
	FmtLong             // "l"
	FmtComma            // ","
	FmtByte             // "hh"
	FmtBody             // for printing export bodies
)

type ForwardType

type ForwardType struct {
	Copyto      []*Node // where to copy the eventual value to
	Embedlineno int32   // first use of this type as an embedded type
}

ForwardType contains Type fields specific to forward types.

type Funarg

type Funarg uint8

Fnstruct records the kind of function argument

const (
	FunargNone    Funarg = iota
	FunargRcvr           // receiver
	FunargParams         // input parameters
	FunargResults        // output results
)

type Func

type Func struct {
	Shortname  *Node
	Enter      Nodes // for example, allocate and initialize memory for escaping parameters
	Exit       Nodes
	Cvars      Nodes   // closure params
	Dcl        []*Node // autodcl for this func/closure
	Inldcl     Nodes   // copy of dcl for use in inlining
	Closgen    int
	Outerfunc  *Node // outer function (for closure)
	FieldTrack map[*Sym]struct{}
	Ntype      *Node // signature
	Top        int   // top context (Ecall, Eproc, etc)
	Closure    *Node // OCLOSURE <-> ODCLFUNC
	FCurfn     *Node
	Nname      *Node

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

	Endlineno int32
	WBLineno  int32 // line number of first write barrier

	Pragma        Pragma // go:xxx function annotations
	Dupok         bool   // duplicate definitions ok
	Wrapper       bool   // is method wrapper
	Needctxt      bool   // function uses context register (has closure variables)
	ReflectMethod bool   // function calls reflect.Type.Method or MethodByName
}

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

type FuncArgsType

type FuncArgsType struct {
	T *Type // reference to a func type whose elements need a width check
}

// FuncArgsType contains Type fields specific to TFUNCARGS types.

type FuncType

type FuncType struct {
	Receiver *Type // function receiver
	Results  *Type // function results
	Params   *Type // function params

	Nname *Node

	// Argwid is the total width of the function receiver, params, and results.
	// It gets calculated via a temporary TFUNCARGS type.
	// Note that TFUNC's Width is Widthptr.
	Argwid int64

	Outnamed bool
}

FuncType contains Type fields specific to func types.

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 InitEntry

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

type InitPlan

type InitPlan struct {
	E []InitEntry
}

type InterMethType

type InterMethType struct {
	Nname *Node
}

InterMethType contains Type fields specific to interface method psuedo-types.

type InterType

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

InterType contains Type fields specific to interface types.

type Iter

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

Iter provides an abstraction for iterating across struct fields and interface methods.

func (*Iter) Next

func (i *Iter) Next() *Field

Next returns the next field or method, if any.

type Label

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

	// 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 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 MapType

type MapType struct {
	Key *Type // Key type
	Val *Type // Val (elem) type

	Bucket *Type // internal struct type representing a hash bucket
	Hmap   *Type // internal struct type representing the Hmap (map header object)
	Hiter  *Type // internal struct type representing hash iterator state
}

MapType contains Type fields specific to maps.

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) Add

func (a *Mpflt) Add(b *Mpflt)

func (*Mpflt) AddFloat64

func (a *Mpflt) AddFloat64(c float64)

func (*Mpflt) Cmp

func (a *Mpflt) Cmp(b *Mpflt) int

func (*Mpflt) CmpFloat64

func (a *Mpflt) CmpFloat64(c float64) int

func (*Mpflt) Float32

func (a *Mpflt) Float32() float64

func (*Mpflt) Float64

func (a *Mpflt) Float64() float64

func (*Mpflt) Mul

func (a *Mpflt) Mul(b *Mpflt)

func (*Mpflt) MulFloat64

func (a *Mpflt) MulFloat64(c float64)

func (*Mpflt) Neg

func (a *Mpflt) Neg()

func (*Mpflt) Quo

func (a *Mpflt) Quo(b *Mpflt)

func (*Mpflt) Set

func (a *Mpflt) Set(b *Mpflt)

func (*Mpflt) SetFloat64

func (a *Mpflt) SetFloat64(c float64)

func (*Mpflt) SetInt

func (a *Mpflt) SetInt(b *Mpint)

func (*Mpflt) SetString

func (a *Mpflt) SetString(as string)

floating point input required syntax is [+-]d*[.]d*[e[+-]d*] or [+-]0xH*[e[+-]d*]

func (*Mpflt) String

func (f *Mpflt) String() string

func (*Mpflt) Sub

func (a *Mpflt) Sub(b *Mpflt)

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) Add

func (a *Mpint) Add(b *Mpint)

func (*Mpint) And

func (a *Mpint) And(b *Mpint)

func (*Mpint) AndNot

func (a *Mpint) AndNot(b *Mpint)

func (*Mpint) Cmp

func (a *Mpint) Cmp(b *Mpint) int

func (*Mpint) CmpInt64

func (a *Mpint) CmpInt64(c int64) int

func (*Mpint) Int64

func (a *Mpint) Int64() int64

func (*Mpint) Lsh

func (a *Mpint) Lsh(b *Mpint)

func (*Mpint) Mul

func (a *Mpint) Mul(b *Mpint)

func (*Mpint) Neg

func (a *Mpint) Neg()

func (*Mpint) Or

func (a *Mpint) Or(b *Mpint)

func (*Mpint) Quo

func (a *Mpint) Quo(b *Mpint)

func (*Mpint) Rem

func (a *Mpint) Rem(b *Mpint)

func (*Mpint) Rsh

func (a *Mpint) Rsh(b *Mpint)

func (*Mpint) Set

func (a *Mpint) Set(b *Mpint)

func (*Mpint) SetFloat

func (a *Mpint) SetFloat(b *Mpflt) int

func (*Mpint) SetInt64

func (a *Mpint) SetInt64(c int64)

func (*Mpint) SetOverflow

func (a *Mpint) SetOverflow()

func (*Mpint) SetString

func (a *Mpint) SetString(as string)

func (*Mpint) String

func (x *Mpint) String() string

func (*Mpint) Sub

func (a *Mpint) Sub(b *Mpint)

func (*Mpint) Xor

func (a *Mpint) Xor(b *Mpint)

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 (could move to Param?)
	Inlvar    *Node  // ONAME substitute while inlining (could move to Param?)
	Defn      *Node  // initializing assignment
	Curfn     *Node  // function for local variables
	Param     *Param // additional fields for ONAME, ODCLFIELD
	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
	Keepalive bool // mark value live across unknown assembly call
}

Name holds Node fields used only by named nodes (ONAME, OPACK, OLABEL, ODCLFIELD, 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 Nodes
	Nbody Nodes
	List  Nodes
	Rlist Nodes

	// 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

	// Various. Usually an offset into a struct. For example, ONAME nodes
	// that refer to local variables use it to identify their stack frame
	// position. ODOT, ODOTPTR, and OINDREG use it to indicate offset
	// relative to their base address. ONAME nodes on the left side of an
	// OKEY within an OSTRUCTLIT use it to store the named field's offset.
	// OXCASE and OXFALL use it to validate the use of fallthrough.
	// Possibly still more uses. If you find any, document them.
	Xoffset int64

	Lineno int32

	// OREGISTER, OINDREG
	Reg int16

	Esc uint16 // EscXXX

	Op        Op
	Ullman    uint8 // sethi/ullman number
	Addable   bool  // addressable
	Etype     EType // op for OASOP, etype for OTYPE, exclam for export, 6g saved reg, ChanDir for OTCHAN
	Bounded   bool  // bounds check unnecessary
	NonNil    bool  // guaranteed to be non-nil
	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
	// 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 AutoVar

func AutoVar(v *ssa.Value) (*Node, int64)

AutoVar returns a *Node and int64 representing the auto variable and offset within it where v should be spilled.

func CgenTemp

func CgenTemp(n *Node) *Node

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

func NegOne

func NegOne(t *Type) *Node

NegOne returns a Node of type t with value -1.

func Nod

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

func NodSym

func NodSym(op Op, left *Node, sym *Sym) *Node

NodSym makes a Node with Op op and with the Left field set to left and the Sym field set to sym. This is for ODOT and friends.

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) HasBreak

func (n *Node) HasBreak() bool

func (*Node) Int64

func (n *Node) Int64() int64

Int64 returns n as an int64. n must be an integer or rune constant.

func (*Node) IntLiteral

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

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

func (*Node) Line

func (n *Node) Line() string

func (*Node) NotLiveAtEnd

func (n *Node) NotLiveAtEnd() bool

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) SetHasBreak

func (n *Node) SetHasBreak(b bool)

func (*Node) SetInt

func (n *Node) SetInt(i int64)

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

func (*Node) SetNotLiveAtEnd

func (n *Node) SetNotLiveAtEnd(b bool)

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) SetSliceBounds

func (n *Node) SetSliceBounds(low, high, max *Node)

SetSliceBounds sets n's slice bounds, where n is a slice expression. n must be a slice expression. If max is non-nil, n must be a full slice expression.

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) SliceBounds

func (n *Node) SliceBounds() (low, high, max *Node)

SliceBounds returns n's slice bounds: low, high, and max in expr[low:high:max]. n must be a slice expression. max is nil if n is a simple slice expression.

func (*Node) String

func (n *Node) String() string

func (*Node) Typ

func (n *Node) Typ() ssa.Type

func (*Node) Val

func (n *Node) Val() Val

Val returns the Val for the node.

type NodeEscState

type NodeEscState struct {
	Curfn             *Node
	Escflowsrc        []EscStep // flow(this, src)
	Escretval         Nodes     // 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
	Maxextraloopdepth int32
}

type Nodes

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

Nodes is a pointer to a slice of *Node. For fields that are not used in most nodes, this is used instead of a slice to save space.

func (Nodes) Addr

func (n Nodes) Addr(i int) **Node

Addr returns the address of the i'th element of Nodes. It panics if n does not have at least i+1 elements.

func (*Nodes) Append

func (n *Nodes) Append(a ...*Node)

Append appends entries to Nodes. If a slice is passed in, this will take ownership of it.

func (*Nodes) AppendNodes

func (n *Nodes) AppendNodes(n2 *Nodes)

AppendNodes appends the contents of *n2 to n, then clears n2.

func (Nodes) First

func (n Nodes) First() *Node

First returns the first element of Nodes (same as n.Index(0)). It panics if n has no elements.

func (Nodes) Index

func (n Nodes) Index(i int) *Node

Index returns the i'th element of Nodes. It panics if n does not have at least i+1 elements.

func (Nodes) Len

func (n Nodes) Len() int

Len returns the number of entries in Nodes.

func (*Nodes) MoveNodes

func (n *Nodes) MoveNodes(n2 *Nodes)

MoveNodes sets n to the contents of n2, then clears n2.

func (Nodes) Second

func (n Nodes) Second() *Node

Second returns the second element of Nodes (same as n.Index(1)). It panics if n has fewer than two elements.

func (*Nodes) Set

func (n *Nodes) Set(s []*Node)

Set sets n to a slice. This takes ownership of the slice.

func (*Nodes) Set1

func (n *Nodes) Set1(node *Node)

Set1 sets n to a slice containing a single node.

func (Nodes) SetIndex

func (n Nodes) SetIndex(i int, node *Node)

SetIndex sets the i'th element of Nodes to node. It panics if n does not have at least i+1 elements.

func (Nodes) Slice

func (n Nodes) Slice() []*Node

Slice returns the entries in Nodes as a slice. Changes to the slice entries (as in s[i] = n) will be reflected in the Nodes.

func (Nodes) String

func (n Nodes) 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 >.

func (Op) GoString

func (o Op) GoString() string

func (Op) IsSlice3

func (o Op) IsSlice3() bool

IsSlice3 reports whether o is a slice3 op (OSLICE3, OSLICE3ARR). o must be a slicing op.

func (Op) String

func (o Op) String() string

type OpPrec

type OpPrec int
const (
	// Precedences of binary operators (must be > 0).
	PCOMM OpPrec = 1 + iota
	POROR
	PANDAND
	PCMP
	PADD
	PMUL
)

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 PAUTOHEAP
	Stackcopy *Node // the PPARAM/PPARAMOUT on-stack slot (moved func params only)

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

	// ONAME closure linkage
	// Consider:
	//
	//	func f() {
	//		x := 1 // x1
	//		func() {
	//			use(x) // x2
	//			func() {
	//				use(x) // x3
	//				--- parser is here ---
	//			}()
	//		}()
	//	}
	//
	// There is an original declaration of x and then a chain of mentions of x
	// leading into the current function. Each time x is mentioned in a new closure,
	// we create a variable representing x for use in that specific closure,
	// since the way you get to x is different in each closure.
	//
	// Let's number the specific variables as shown in the code:
	// x1 is the original x, x2 is when mentioned in the closure,
	// and x3 is when mentioned in the closure in the closure.
	//
	// We keep these linked (assume N > 1):
	//
	//   - x1.Defn = original declaration statement for x (like most variables)
	//   - x1.Innermost = current innermost closure x (in this case x3), or nil for none
	//   - x1.isClosureVar() = false
	//
	//   - xN.Defn = x1, N > 1
	//   - xN.isClosureVar() = true, N > 1
	//   - x2.Outer = nil
	//   - xN.Outer = x(N-1), N > 2
	//
	//
	// When we look up x in the symbol table, we always get x1.
	// Then we can use x1.Innermost (if not nil) to get the x
	// for the innermost known closure function,
	// but the first reference in a closure will find either no x1.Innermost
	// or an x1.Innermost with .Funcdepth < Funcdepth.
	// In that case, a new xN must be created, linked in with:
	//
	//     xN.Defn = x1
	//     xN.Outer = x1.Innermost
	//     x1.Innermost = xN
	//
	// When we finish the function, we'll process its closure variables
	// and find xN and pop it off the list using:
	//
	//     x1 := xN.Defn
	//     x1.Innermost = xN.Outer
	//
	// We leave xN.Innermost set so that we can still get to the original
	// variable quickly. Not shown here, but once we're
	// done parsing a function and no longer need xN.Outer for the
	// lexical x reference links as described above, closurebody
	// recomputes xN.Outer as the semantic x reference link tree,
	// even filling in x in intermediate closures that might not
	// have mentioned it along the way to inner closures that did.
	// See closurebody for details.
	//
	// During the eventual compilation, then, for closure variables we have:
	//
	//     xN.Defn = original variable
	//     xN.Outer = variable captured in next outward scope
	//                to make closure where xN appears
	//
	// Because of the sharding of pieces of the node, x.Defn means x.Name.Defn
	// and x.Innermost/Outer means x.Name.Param.Innermost/Outer.
	Innermost *Node
	Outer     *Node
}

type Pkg

type Pkg struct {
	Name     string // package name, e.g. "sys"
	Path     string // string literal used in import statement, e.g. "runtime/internal/sys"
	Pathsym  *obj.LSym
	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 Pragma

type Pragma uint16
const (
	Nointerface       Pragma = 1 << iota
	Noescape                 // func parameters don't escape
	Norace                   // func must not have race detector annotations
	Nosplit                  // func should not execute on separate stack
	Noinline                 // func should not be inlined
	Systemstack              // func must run on system stack
	Nowritebarrier           // emit compiler error instead of write barrier
	Nowritebarrierrec        // error on write barrier in this or recursive callees
	CgoUnsafeArgs            // treat a pointer to one arg as a pointer to them all
)

type PtrType

type PtrType struct {
	Elem *Type // element type
}

PtrType contains Type fields specific to pointer types.

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 SSAGenState

type SSAGenState struct {
	// Branches remembers all the branch instructions we've seen
	// and where they would like to go.
	Branches []Branch
	// contains filtered or unexported fields
}

SSAGenState contains state needed during Prog generation.

func (*SSAGenState) Pc

func (s *SSAGenState) Pc() *obj.Prog

Pc returns the current Prog.

func (*SSAGenState) SetLineno

func (s *SSAGenState) SetLineno(l int32)

SetLineno sets the current source line number.

type Sig

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

type SliceType

type SliceType struct {
	Elem *Type // element type
}

SliceType contains Type fields specific to slice types.

type StructType

type StructType struct {

	// Maps have three associated internal structs (see struct MapType).
	// Map links such structs back to their map type.
	Map *Type

	Funarg      Funarg // type of function arguments for arg struct
	Haspointers uint8  // 0 unknown, 1 no, 2 yes
	// contains filtered or unexported fields
}

StructType contains Type fields specific to struct types.

type Sym

type Sym struct {
	Flags     SymFlags
	Link      *Sym
	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
	Block      int32  // blocknumber to catch redeclaration
	Lastlineno int32  // last declaration for diagnostic

	Label   *Label // corresponding label (ephemeral)
	Origpkg *Pkg   // original package for . import
	Lsym    *obj.LSym
	Fsym    *Sym // funcsym
}

Sym represents an object name. Most commonly, this is a Go identifier naming an object declared within a package, but Syms are also used to name internal synthesized objects.

As a special exception, field and method names that are exported use the Sym associated with localpkg instead of the package that declared them. This allows using Sym pointer equality to test for Go identifier uniqueness when handling selector expressions.

func Lookup

func Lookup(name string) *Sym

func LookupBytes

func LookupBytes(name []byte) *Sym

func LookupN

func LookupN(prefix string, n int) *Sym

LookupN looks up the symbol starting with prefix and ending with the decimal n. If prefix is too long, LookupN panics.

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 SymFlags

type SymFlags uint8
const (
	SymExport SymFlags = 1 << iota // to be exported
	SymPackage
	SymExported // already written out by export
	SymUniq
	SymSiggen
	SymAsm
	SymAlgGen
)
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 {
	// Extra contains extra etype-specific fields.
	// As an optimization, those etype-specific structs which contain exactly
	// one pointer-shaped field are stored as values rather than pointers when possible.
	//
	// TMAP: *MapType
	// TFORW: *ForwardType
	// TFUNC: *FuncType
	// TINTERMETHOD: InterMethType
	// TSTRUCT: *StructType
	// TINTER: *InterType
	// TDDDFIELD: DDDFieldType
	// TFUNCARGS: FuncArgsType
	// TCHANARGS: ChanArgsType
	// TCHAN: *ChanType
	// TPTR32, TPTR64: PtrType
	// TARRAY: *ArrayType
	// TSLICE: SliceType
	Extra interface{}

	// Width is the width of this Type in bytes.
	Width int64

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

	Sym    *Sym  // symbol containing name, for named types
	Vargen int32 // unique name for OTYPE/ONAME
	Lineno int32 // line at which this type was declared, implicitly or explicitly

	Etype      EType // kind of type
	Noalg      bool  // suppress hash and eq algorithm generation
	Trecur     uint8 // to detect loops
	Printed    bool  // prevent duplicate export printing
	Local      bool  // created in this file
	Deferwidth bool
	Broke      bool  // broken type definition.
	Align      uint8 // the required alignment of this type, in bytes
	// contains filtered or unexported fields
}

A Type represents a Go type.

func Ptrto

func Ptrto(t *Type) *Type

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

func (*Type) Alignment

func (t *Type) Alignment() int64

func (*Type) AllMethods

func (t *Type) AllMethods() *Fields

func (*Type) ArgWidth

func (t *Type) ArgWidth() int64

ArgWidth returns the total aligned argument size for a function. It includes the receiver, parameters, and results.

func (*Type) ChanArgs

func (t *Type) ChanArgs() *Type

ChanArgs returns the channel type for TCHANARGS type t.

func (*Type) ChanDir

func (t *Type) ChanDir() ChanDir

ChanDir returns the direction of a channel type t. The direction will be one of Crecv, Csend, or Cboth.

func (*Type) ChanType

func (t *Type) ChanType() *ChanType

ChanType returns t's extra channel-specific fields.

func (*Type) Compare

func (t *Type) Compare(u ssa.Type) ssa.Cmp

Compare compares types for purposes of the SSA back end, returning an ssa.Cmp (one of CMPlt, CMPeq, CMPgt). The answers are correct for an optimizer or code generator, but not necessarily typechecking. The order chosen is arbitrary, only consistency and division into equivalence classes (Types that compare CMPeq) matters.

func (*Type) Copy

func (t *Type) Copy() *Type

Copy returns a shallow copy of the Type.

func (*Type) DDDField

func (t *Type) DDDField() *Type

DDDField returns the slice ... type for TDDDFIELD type t.

func (*Type) Elem

func (t *Type) Elem() *Type

Elem returns the type of elements of t. Usable with pointers, channels, arrays, and slices.

func (*Type) ElemType

func (t *Type) ElemType() ssa.Type

func (*Type) Field

func (t *Type) Field(i int) *Field

Field returns the i'th field/method of struct/interface type t.

func (*Type) FieldName

func (t *Type) FieldName(i int) string

func (*Type) FieldOff

func (t *Type) FieldOff(i int) int64

func (*Type) FieldSlice

func (t *Type) FieldSlice() []*Field

FieldSlice returns a slice of containing all fields/methods of struct/interface type t.

func (*Type) FieldType

func (t *Type) FieldType(i int) ssa.Type

func (*Type) Fields

func (t *Type) Fields() *Fields

func (*Type) ForwardType

func (t *Type) ForwardType() *ForwardType

ForwardType returns t's extra forward-type-specific fields.

func (*Type) FuncArgs

func (t *Type) FuncArgs() *Type

FuncArgs returns the channel type for TFUNCARGS type t.

func (*Type) FuncType

func (t *Type) FuncType() *FuncType

FuncType returns t's extra func-specific fields.

func (*Type) IncomparableField

func (t *Type) IncomparableField() *Field

IncomparableField returns an incomparable Field of struct Type t, if any.

func (*Type) IsArray

func (t *Type) IsArray() bool

func (*Type) IsBoolean

func (t *Type) IsBoolean() bool

func (*Type) IsChan

func (t *Type) IsChan() bool

func (*Type) IsComparable

func (t *Type) IsComparable() bool

IsComparable reports whether t is a comparable type.

func (*Type) IsComplex

func (t *Type) IsComplex() bool

func (*Type) IsEmptyInterface

func (t *Type) IsEmptyInterface() bool

IsEmptyInterface reports whether t is an empty interface type.

func (*Type) IsFlags

func (t *Type) IsFlags() bool

func (*Type) IsFloat

func (t *Type) IsFloat() bool

func (*Type) IsFuncArgStruct

func (t *Type) IsFuncArgStruct() bool

IsFuncArgStruct reports whether t is a struct representing function parameters.

func (*Type) IsInteger

func (t *Type) IsInteger() bool

func (*Type) IsInterface

func (t *Type) IsInterface() bool

func (*Type) IsKind

func (t *Type) IsKind(et EType) bool

IsKind reports whether t is a Type of the specified kind.

func (*Type) IsMap

func (t *Type) IsMap() bool

func (*Type) IsMemory

func (t *Type) IsMemory() bool

func (*Type) IsPtr

func (t *Type) IsPtr() bool

IsPtr reports whether t is a regular Go pointer type. This does not include unsafe.Pointer.

func (*Type) IsPtrShaped

func (t *Type) IsPtrShaped() bool

IsPtrShaped reports whether t is represented by a single machine pointer. In addition to regular Go pointer types, this includes map, channel, and function types and unsafe.Pointer. It does not include array or struct types that consist of a single pointer shaped type. TODO(mdempsky): Should it? See golang.org/issue/15028.

func (*Type) IsRegularMemory

func (t *Type) IsRegularMemory() bool

IsRegularMemory reports whether t can be compared/hashed as regular memory.

func (*Type) IsSigned

func (t *Type) IsSigned() bool

func (*Type) IsSlice

func (t *Type) IsSlice() bool

func (*Type) IsString

func (t *Type) IsString() bool

func (*Type) IsStruct

func (t *Type) IsStruct() bool

func (*Type) IsUnsafePtr

func (t *Type) IsUnsafePtr() bool

IsUnsafePtr reports whether t is an unsafe pointer.

func (*Type) IsUntyped

func (t *Type) IsUntyped() bool

IsUntyped reports whether t is an untyped type.

func (*Type) IsVoid

func (t *Type) IsVoid() bool

func (*Type) Key

func (t *Type) Key() *Type

Key returns the key type of map type t.

func (*Type) MapType

func (t *Type) MapType() *MapType

MapType returns t's extra map-specific fields.

func (*Type) Methods

func (t *Type) Methods() *Fields

func (*Type) Nname

func (t *Type) Nname() *Node

Nname returns the associated function's nname.

func (*Type) NumElem

func (t *Type) NumElem() int64

func (*Type) NumFields

func (t *Type) NumFields() int

func (*Type) Params

func (t *Type) Params() *Type

func (*Type) ParamsP

func (t *Type) ParamsP() **Type

func (*Type) PtrTo

func (t *Type) PtrTo() ssa.Type

func (*Type) Recv

func (t *Type) Recv() *Field

Recv returns the receiver of function type t, if any.

func (*Type) Recvs

func (t *Type) Recvs() *Type

func (*Type) RecvsP

func (t *Type) RecvsP() **Type

func (*Type) Results

func (t *Type) Results() *Type

func (*Type) ResultsP

func (t *Type) ResultsP() **Type

func (*Type) SetFields

func (t *Type) SetFields(fields []*Field)

SetFields sets struct/interface type t's fields/methods to fields.

func (*Type) SetNname

func (t *Type) SetNname(n *Node)

Nname sets the associated function's nname.

func (*Type) SetNumElem

func (t *Type) SetNumElem(n int64)

SetNumElem sets the number of elements in an array type. The only allowed use is on array types created with typDDDArray. For other uses, create a new array with typArray instead.

func (*Type) SimpleString

func (t *Type) SimpleString() string

func (*Type) Size

func (t *Type) Size() int64

func (*Type) String

func (t *Type) String() string

func (*Type) StructType

func (t *Type) StructType() *StructType

StructType returns t's extra struct-specific fields.

func (*Type) Val

func (t *Type) Val() *Type

Val returns the value type of map type t.

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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