Documentation ¶
Index ¶
- Constants
- Variables
- func Aconv(a As) string
- func Bool2int(b bool) int
- func CConv(s uint8) string
- func Cputime() float64
- func Dconv(p *Prog, a *Addr) string
- func Expstring() string
- func Flagcount(name, usage string, val *int)
- func Flagfn0(name, usage string, f func())
- func Flagfn1(name, usage string, f func(string))
- func Flagfn2(string, string, func(string, string))
- func Flagint32(name, usage string, val *int32)
- func Flagint64(name, usage string, val *int64)
- func Flagparse(usage func())
- func Flagprint(fd int)
- func Flagstr(name, usage string, val *string)
- func Flushplist(ctxt *Link)
- func FlushplistNoFree(ctxt *Link)
- func Getcallerpc(interface{}) uintptr
- func Getgo386() string
- func Getgoarch() string
- func Getgoarm() int32
- func Getgoextlinkenabled() string
- func Getgoos() string
- func Getgoroot() string
- func Getgoversion() string
- func Headstr(v int) string
- func Linkprfile(ctxt *Link, line int)
- func Linksymfmt(s *LSym) string
- func Mconv(a *Addr) string
- func Nopout(p *Prog)
- func Rconv(reg int) string
- func RegisterOpcode(lo As, Anames []string)
- func RegisterRegister(lo, hi int, Rconv func(int) string)
- func Setuintxx(ctxt *Link, s *LSym, off int64, v uint64, wid int64) int64
- func WriteObjFile(ctxt *Link, b *bio.Writer)
- func Writeobjdirect(ctxt *Link, b *bio.Writer)
- type Addr
- type AddrType
- type As
- type AsmBuf
- func (a *AsmBuf) Bytes() []byte
- func (a *AsmBuf) Insert(i int, b byte)
- func (a *AsmBuf) Last() byte
- func (a *AsmBuf) Len() int
- func (a *AsmBuf) Peek(i int) byte
- func (a *AsmBuf) Put(b []byte)
- func (a *AsmBuf) Put1(x byte)
- func (a *AsmBuf) Put2(x, y byte)
- func (a *AsmBuf) Put3(x, y, z byte)
- func (a *AsmBuf) Put4(x, y, z, w byte)
- func (a *AsmBuf) PutInt16(v int16)
- func (a *AsmBuf) PutInt32(v int32)
- func (a *AsmBuf) PutInt64(v int64)
- func (a *AsmBuf) Reset()
- type Auto
- type LSym
- func (s *LSym) Grow(lsiz int64)
- func (s *LSym) GrowCap(c int64)
- func (s *LSym) String() string
- func (s *LSym) WriteAddr(ctxt *Link, off int64, siz int, rsym *LSym, roff int64)
- func (s *LSym) WriteBytes(ctxt *Link, off int64, b []byte) int64
- func (s *LSym) WriteFloat32(ctxt *Link, off int64, f float32)
- func (s *LSym) WriteFloat64(ctxt *Link, off int64, f float64)
- func (s *LSym) WriteInt(ctxt *Link, off int64, siz int, i int64)
- func (s *LSym) WriteOff(ctxt *Link, off int64, rsym *LSym, roff int64)
- func (s *LSym) WriteString(ctxt *Link, off int64, siz int, str string)
- type LineHist
- func (h *LineHist) AbsFileLine(lineno int) (file string, line int)
- func (h *LineHist) At(lineno int) *LineStack
- func (h *LineHist) FileLine(lineno int) (file string, line int)
- func (h *LineHist) LineString(lineno int) string
- func (h *LineHist) Pop(lineno int)
- func (h *LineHist) Push(lineno int, file string)
- func (h *LineHist) Update(lineno int, file string, line int)
- type LineRange
- type LineStack
- type Link
- type LinkArch
- type Pcdata
- type Pcln
- type Plist
- type Prog
- type ProgInfo
- type Reloc
- type SymVer
Constants ¶
const ( PCDATA_StackMapIndex = 0 FUNCDATA_ArgsPointerMaps = 0 FUNCDATA_LocalsPointerMaps = 1 ArgsSizeUnknown = -0x80000000 )
ArgsSizeUnknown is set in Func.argsize to mark all functions whose argument size is unknown (C vararg functions, and assembly code without an explicit specification). This value is generated by the compiler, assembler, or linker.
const ( NAME_NONE = 0 + iota NAME_EXTERN NAME_STATIC NAME_AUTO NAME_PARAM // A reference to name@GOT(SB) is a reference to the entry in the global offset // table for 'name'. NAME_GOTREF )
const ( ABase386 = (1 + iota) << 12 ABaseARM ABaseAMD64 ABasePPC64 ABaseARM64 ABaseMIPS64 ABaseS390X AMask = 1<<12 - 1 // AND with this to use the opcode as an array index. )
Each architecture is allotted a distinct subspace of opcode values for declaring its arch-specific opcodes. Within this subspace, the first arch-specific opcode should be at offset A_ARCHSPECIFIC.
Subspaces are aligned to a power of two so opcodes can be masked with AMask and used as compact array indices.
const ( Sxxx = iota STEXT SELFRXSECT STYPE SSTRING SGOSTRING SGOSTRINGHDR SGOFUNC SGCBITS SRODATA SFUNCTAB // Types STYPE-SFUNCTAB above are written to the .rodata section by default. // When linking a shared object, some conceptually "read only" types need to // be written to by relocations and putting them in a section called // ".rodata" interacts poorly with the system linkers. The GNU linkers // support this situation by arranging for sections of the name // ".data.rel.ro.XXX" to be mprotected read only by the dynamic linker after // relocations have applied, so when the Go linker is creating a shared // object it checks all objects of the above types and bumps any object that // has a relocation to it to the corresponding type below, which are then // written to sections with appropriate magic names. STYPERELRO SSTRINGRELRO SGOSTRINGRELRO SGOSTRINGHDRRELRO SGOFUNCRELRO SGCBITSRELRO SRODATARELRO SFUNCTABRELRO STYPELINK SITABLINK SSYMTAB SPCLNTAB SELFROSECT SMACHOPLT SELFSECT SMACHO SMACHOGOT SWINDOWS SELFGOT SNOPTRDATA SINITARR SDATA SBSS SNOPTRBSS STLSBSS SXREF SMACHOSYMSTR SMACHOSYMTAB SMACHOINDIRECTPLT SMACHOINDIRECTGOT SFILE SFILEPATH SCONST SDYNIMPORT SHOSTOBJ SDWARFSECT SDWARFINFO SSUB = 1 << 8 SMASK = SSUB - 1 SHIDDEN = 1 << 9 SCONTAINER = 1 << 10 // has a sub-symbol )
LSym.type
const ( R_ADDR = 1 + iota // R_ADDRPOWER relocates a pair of "D-form" instructions (instructions with 16-bit // immediates in the low half of the instruction word), usually addis followed by // another add or a load, inserting the "high adjusted" 16 bits of the address of // the referenced symbol into the immediate field of the first instruction and the // low 16 bits into that of the second instruction. R_ADDRPOWER // R_ADDRARM64 relocates an adrp, add pair to compute the address of the // referenced symbol. R_ADDRARM64 // R_ADDRMIPS (only used on mips64) resolves to a 32-bit external address, // by loading the address into a register with two instructions (lui, ori). R_ADDRMIPS // R_ADDROFF resolves to a 32-bit offset from the beginning of the section // holding the data being relocated to the referenced symbol. R_ADDROFF R_SIZE R_CALL R_CALLARM R_CALLARM64 R_CALLIND R_CALLPOWER // R_CALLMIPS (only used on mips64) resolves to non-PC-relative target address // of a CALL (JAL) instruction, by encoding the address into the instruction. R_CALLMIPS R_CONST R_PCREL // R_TLS_LE, used on 386, amd64, and ARM, resolves to the offset of the // thread-local symbol from the thread local base and is used to implement the // "local exec" model for tls access (r.Sym is not set on intel platforms but is // set to a TLS symbol -- runtime.tlsg -- in the linker when externally linking). R_TLS_LE // R_TLS_IE, used 386, amd64, and ARM resolves to the PC-relative offset to a GOT // slot containing the offset from the thread-local symbol from the thread local // base and is used to implemented the "initial exec" model for tls access (r.Sym // is not set on intel platforms but is set to a TLS symbol -- runtime.tlsg -- in // the linker when externally linking). R_TLS_IE R_GOTOFF R_PLT0 R_PLT1 R_PLT2 R_USEFIELD // R_USETYPE resolves to an *rtype, but no relocation is created. The // linker uses this as a signal that the pointed-to type information // should be linked into the final binary, even if there are no other // direct references. (This is used for types reachable by reflection.) R_USETYPE // R_METHODOFF resolves to a 32-bit offset from the beginning of the section // holding the data being relocated to the referenced symbol. // It is a variant of R_ADDROFF used when linking from the uncommonType of a // *rtype, and may be set to zero by the linker if it determines the method // text is unreachable by the linked program. R_METHODOFF R_POWER_TOC R_GOTPCREL // R_JMPMIPS (only used on mips64) resolves to non-PC-relative target address // of a JMP instruction, by encoding the address into the instruction. // The stack nosplit check ignores this since it is not a function call. R_JMPMIPS // R_DWARFREF resolves to the offset of the symbol from its section. R_DWARFREF // Set a MOV[NZ] immediate field to bits [15:0] of the offset from the thread // local base to the thread local variable defined by the referenced (thread // local) symbol. Error if the offset does not fit into 16 bits. R_ARM64_TLS_LE // Relocates an ADRP; LD64 instruction sequence to load the offset between // the thread local base and the thread local variable defined by the // referenced (thread local) symbol from the GOT. R_ARM64_TLS_IE // R_ARM64_GOTPCREL relocates an adrp, ld64 pair to compute the address of the GOT // slot of the referenced symbol. R_ARM64_GOTPCREL // R_POWER_TLS_LE is used to implement the "local exec" model for tls // access. It resolves to the offset of the thread-local symbol from the // thread pointer (R13) and inserts this value into the low 16 bits of an // instruction word. R_POWER_TLS_LE // R_POWER_TLS_IE is used to implement the "initial exec" model for tls access. It // relocates a D-form, DS-form instruction sequence like R_ADDRPOWER_DS. It // inserts to the offset of GOT slot for the thread-local symbol from the TOC (the // GOT slot is filled by the dynamic linker with the offset of the thread-local // symbol from the thread pointer (R13)). R_POWER_TLS_IE // R_POWER_TLS marks an X-form instruction such as "MOVD 0(R13)(R31*1), g" as // accessing a particular thread-local symbol. It does not affect code generation // but is used by the system linker when relaxing "initial exec" model code to // "local exec" model code. R_POWER_TLS // R_ADDRPOWER_DS is similar to R_ADDRPOWER above, but assumes the second // instruction is a "DS-form" instruction, which has an immediate field occupying // bits [15:2] of the instruction word. Bits [15:2] of the address of the // relocated symbol are inserted into this field; it is an error if the last two // bits of the address are not 0. R_ADDRPOWER_DS // R_ADDRPOWER_PCREL relocates a D-form, DS-form instruction sequence like // R_ADDRPOWER_DS but inserts the offset of the GOT slot for the referenced symbol // from the TOC rather than the symbol's address. R_ADDRPOWER_GOT // R_ADDRPOWER_PCREL relocates two D-form instructions like R_ADDRPOWER, but // inserts the displacement from the place being relocated to the address of the // the relocated symbol instead of just its address. R_ADDRPOWER_PCREL // R_ADDRPOWER_TOCREL relocates two D-form instructions like R_ADDRPOWER, but // inserts the offset from the TOC to the address of the the relocated symbol // rather than the symbol's address. R_ADDRPOWER_TOCREL // R_ADDRPOWER_TOCREL relocates a D-form, DS-form instruction sequence like // R_ADDRPOWER_DS but inserts the offset from the TOC to the address of the the // relocated symbol rather than the symbol's address. R_ADDRPOWER_TOCREL_DS // R_PCRELDBL relocates s390x 2-byte aligned PC-relative addresses. // TODO(mundaym): remove once variants can be serialized - see issue 14218. R_PCRELDBL )
Reloc.type
const ( A_AUTO = 1 + iota A_PARAM )
Auto.name
const ( Hunknown = 0 + iota Hdarwin Hdragonfly Hfreebsd Hlinux Hnacl Hnetbsd Hopenbsd Hplan9 Hsolaris Hwindows )
executable header types
const ( STACKSYSTEM = 0 StackSystem = STACKSYSTEM StackBig = 4096 StackGuard = 720*stackGuardMultiplier + StackSystem StackSmall = 128 StackLimit = StackGuard - StackSystem - StackSmall )
const ( // Don't profile the marked routine. // // Deprecated: Not implemented, do not use. NOPROF = 1 // It is ok for the linker to get multiple of these symbols. It will // pick one of the duplicates to use. DUPOK = 2 // Don't insert stack check preamble. NOSPLIT = 4 // Put this data in a read-only section. RODATA = 8 // This data contains no pointers. NOPTR = 16 // This is a wrapper function and should not count as disabling 'recover'. WRAPPER = 32 // This function uses its incoming context register. NEEDCTXT = 64 // When passed to ggloblsym, causes Local to be set to true on the LSym it creates. LOCAL = 128 // Allocate a word of thread local storage and store the offset from the // thread local base to the thread local storage in this variable. TLSBSS = 256 // Do not insert instructions to allocate a stack frame for this function. // Only valid on functions that declare a frame size of 0. // TODO(mwhudson): only implemented for ppc64x at present. NOFRAME = 512 // Function can call reflect.Type.Method or reflect.Type.MethodByName. REFLECTMETHOD = 1024 )
const ( KindBool = 1 + iota KindInt KindInt8 KindInt16 KindInt32 KindInt64 KindUint KindUint8 KindUint16 KindUint32 KindUint64 KindUintptr KindFloat32 KindFloat64 KindComplex64 KindComplex128 KindArray KindChan KindFunc KindInterface KindMap KindPtr KindSlice KindString KindStruct KindUnsafePointer KindDirectIface = 1 << 5 KindGCProg = 1 << 6 KindNoPointers = 1 << 7 KindMask = (1 << 5) - 1 )
const ( C_SCOND = (1 << 4) - 1 C_SBIT = 1 << 4 C_PBIT = 1 << 5 C_WBIT = 1 << 6 C_FBIT = 1 << 7 C_UBIT = 1 << 7 C_SCOND_XOR = 14 )
ARM scond byte
const ( // Because of masking operations in the encodings, each register // space should start at 0 modulo some power of 2. RBase386 = 1 * 1024 RBaseAMD64 = 2 * 1024 RBaseARM = 3 * 1024 RBasePPC64 = 4 * 1024 // range [4k, 8k) RBaseARM64 = 8 * 1024 // range [8k, 13k) RBaseMIPS64 = 13 * 1024 // range [13k, 14k) RBaseS390X = 14 * 1024 // range [14k, 15k) )
const (
HistVersion = 1
)
symbol version, incremented each time a file is loaded. version==1 is reserved for savehist.
const (
LOG = 5
)
const REG_NONE = 0
const (
StackPreempt = -1314 // 0xfff...fade
)
Variables ¶
var ( Framepointer_enabled int Fieldtrack_enabled int )
var Anames = []string{
"XXX",
"CALL",
"CHECKNIL",
"DUFFCOPY",
"DUFFZERO",
"END",
"FUNCDATA",
"GLOBL",
"JMP",
"NOP",
"PCDATA",
"RET",
"TEXT",
"TYPE",
"UNDEF",
"USEFIELD",
"VARDEF",
"VARKILL",
"VARLIVE",
}
Functions ¶
func Flushplist ¶
func Flushplist(ctxt *Link)
func FlushplistNoFree ¶
func FlushplistNoFree(ctxt *Link)
func Getcallerpc ¶
func Getcallerpc(interface{}) uintptr
func Getgoextlinkenabled ¶
func Getgoextlinkenabled() string
func Getgoversion ¶
func Getgoversion() string
func Linkprfile ¶
func Linksymfmt ¶
func RegisterOpcode ¶
RegisterOpcode binds a list of instruction names to a given instruction number range.
func RegisterRegister ¶
RegisterRegister binds a pretty-printer (Rconv) for register numbers to a given register number range. Lo is inclusive, hi exclusive (valid registers are lo through hi-1).
func WriteObjFile ¶
func Writeobjdirect ¶
The Go and C compilers, and the assembler, call writeobj to write out a Go object file. The linker does not call this; the linker does not write out object files.
Types ¶
type Addr ¶
type Addr struct { Reg int16 Index int16 Scale int16 // Sometimes holds a register. Type AddrType Name int8 Class int8 Etype uint8 Offset int64 Width int64 Sym *LSym Gotype *LSym // argument value: // for TYPE_SCONST, a string // for TYPE_FCONST, a float64 // for TYPE_BRANCH, a *Prog (optional) // for TYPE_TEXTSIZE, an int32 (optional) Val interface{} Node interface{} // for use by compiler }
An Addr is an argument to an instruction. The general forms and their encodings are:
sym±offset(symkind)(reg)(index*scale) Memory reference at address &sym(symkind) + offset + reg + index*scale. Any of sym(symkind), ±offset, (reg), (index*scale), and *scale can be omitted. If (reg) and *scale are both omitted, the resulting expression (index) is parsed as (reg). To force a parsing as index*scale, write (index*1). Encoding: type = TYPE_MEM name = symkind (NAME_AUTO, ...) or 0 (NAME_NONE) sym = sym offset = ±offset reg = reg (REG_*) index = index (REG_*) scale = scale (1, 2, 4, 8) $<mem> Effective address of memory reference <mem>, defined above. Encoding: same as memory reference, but type = TYPE_ADDR. $<±integer value> This is a special case of $<mem>, in which only ±offset is present. It has a separate type for easy recognition. Encoding: type = TYPE_CONST offset = ±integer value *<mem> Indirect reference through memory reference <mem>, defined above. Only used on x86 for CALL/JMP *sym(SB), which calls/jumps to a function pointer stored in the data word sym(SB), not a function named sym(SB). Encoding: same as above, but type = TYPE_INDIR. $*$<mem> No longer used. On machines with actual SB registers, $*$<mem> forced the instruction encoding to use a full 32-bit constant, never a reference relative to SB. $<floating point literal> Floating point constant value. Encoding: type = TYPE_FCONST val = floating point value $<string literal, up to 8 chars> String literal value (raw bytes used for DATA instruction). Encoding: type = TYPE_SCONST val = string <register name> Any register: integer, floating point, control, segment, and so on. If looking for specific register kind, must check type and reg value range. Encoding: type = TYPE_REG reg = reg (REG_*) x(PC) Encoding: type = TYPE_BRANCH val = Prog* reference OR ELSE offset = target pc (branch takes priority) $±x-±y Final argument to TEXT, specifying local frame size x and argument size y. In this form, x and y are integer literals only, not arbitrary expressions. This avoids parsing ambiguities due to the use of - as a separator. The ± are optional. If the final argument to TEXT omits the -±y, the encoding should still use TYPE_TEXTSIZE (not TYPE_CONST), with u.argsize = ArgsSizeUnknown. Encoding: type = TYPE_TEXTSIZE offset = x val = int32(y) reg<<shift, reg>>shift, reg->shift, reg@>shift Shifted register value, for ARM. In this form, reg must be a register and shift can be a register or an integer constant. Encoding: type = TYPE_SHIFT offset = (reg&15) | shifttype<<5 | count shifttype = 0, 1, 2, 3 for <<, >>, ->, @> count = (reg&15)<<8 | 1<<4 for a register shift count, (n&31)<<7 for an integer constant. (reg, reg) A destination register pair. When used as the last argument of an instruction, this form makes clear that both registers are destinations. Encoding: type = TYPE_REGREG reg = first register offset = second register [reg, reg, reg-reg] Register list for ARM. Encoding: type = TYPE_REGLIST offset = bit mask of registers in list; R0 is low bit. reg, reg Register pair for ARM. TYPE_REGREG2 (reg+reg) Register pair for PPC64. Encoding: type = TYPE_MEM reg = first register index = second register scale = 1
type As ¶
type As int16
An As denotes an assembler opcode. There are some portable opcodes, declared here in package obj, that are common to all architectures. However, the majority of opcodes are arch-specific and are declared in their respective architecture's subpackage.
type AsmBuf ¶
type AsmBuf struct {
// contains filtered or unexported fields
}
AsmBuf is a simple buffer to assemble variable-length x86 instructions into.
type LSym ¶
type LSym struct { Name string Type int16 Version int16 Dupok bool Cfunc bool Nosplit bool Leaf bool Seenglobl bool Onlist bool // ReflectMethod means the function may call reflect.Type.Method or // reflect.Type.MethodByName. Matching is imprecise (as reflect.Type // can be used through a custom interface), so ReflectMethod may be // set in some cases when the reflect package is not called. // // Used by the linker to determine what methods can be pruned. ReflectMethod bool // Local means make the symbol local even when compiling Go code to reference Go // symbols in other shared libraries, as in this mode symbols are global by // default. "local" here means in the sense of the dynamic linker, i.e. not // visible outside of the module (shared library or executable) that contains its // definition. (When not compiling to support Go shared libraries, all symbols are // local in this sense unless there is a cgo_export_* directive). Local bool RefIdx int // Index of this symbol in the symbol reference list. Args int32 Locals int32 Size int64 Gotype *LSym Autom *Auto Text *Prog Pcln *Pcln P []byte R []Reloc }
An LSym is the sort of symbol that is written to an object file.
func (*LSym) String ¶
The compiler needs LSym to satisfy fmt.Stringer, because it stores an LSym in ssa.ExternSymbol.
func (*LSym) WriteAddr ¶
WriteAddr writes an address of size siz into s at offset off. rsym and roff specify the relocation for the address.
func (*LSym) WriteBytes ¶
WriteBytes writes a slice of bytes into s at offset off.
func (*LSym) WriteFloat32 ¶
WriteFloat32 writes f into s at offset off.
func (*LSym) WriteFloat64 ¶
WriteFloat64 writes f into s at offset off.
type LineHist ¶
type LineHist struct { Top *LineStack // current top of stack Ranges []LineRange // ranges for lookup Dir string // directory to qualify relative paths TrimPathPrefix string // remove leading TrimPath from recorded file names PrintFilenameOnly bool // ignore path when pretty-printing a line; internal use only GOROOT string // current GOROOT GOROOT_FINAL string // target GOROOT }
A LineHist records the history of the file input stack, which maps the virtual line number, an incrementing count of lines processed in any input file and typically named lineno, to a stack of file:line pairs showing the path of inclusions that led to that position. The first line directive (//line in Go, #line in assembly) is treated as pushing a new entry on the stack, so that errors can report both the actual and translated line number.
In typical use, the virtual lineno begins at 1, and file line numbers also begin at 1, but the only requirements placed upon the numbers by this code are:
- calls to Push, Update, and Pop must be monotonically increasing in lineno
- except as specified by those methods, virtual and file line number increase together, so that given (only) calls Push(10, "x.go", 1) and Pop(15), virtual line 12 corresponds to x.go line 3.
func (*LineHist) AbsFileLine ¶
AbsFileLine returns the absolute file name and line number at the top of the stack for the given lineno.
func (*LineHist) FileLine ¶
FileLine returns the file name and line number at the top of the stack for the given lineno.
func (*LineHist) LineString ¶
LineString returns a string giving the file and line number corresponding to lineno, for use in error messages.
type LineRange ¶
type LineRange struct { Start int // starting lineno Stack *LineStack // top of stack for this range }
The span of valid linenos in the recorded line history can be broken into a set of ranges, each with a particular stack. A LineRange records one such range.
type LineStack ¶
type LineStack struct { Parent *LineStack // parent in inclusion stack Lineno int // virtual line number where this entry takes effect File string // file name used to open source file, for error messages AbsFile string // absolute file name, for pcln tables FileLine int // line number in file at Lineno Directive bool Sym *LSym // for linkgetline - TODO(rsc): remove }
A LineStack is an entry in the recorded line history. Although the history at any given line number is a stack, the record for all line processed forms a tree, with common stack prefixes acting as parents.
type Link ¶
type Link struct { Goarm int32 Headtype int Arch *LinkArch Debugasm int32 Debugvlog int32 Debugdivmod int32 Debugpcln int32 Flag_dynlink bool Flag_optimize bool Bso *bufio.Writer Pathname string Goroot string Goroot_final string Hash map[SymVer]*LSym LineHist LineHist Imports []string Plist *Plist Plast *Plist Sym_div *LSym Sym_divu *LSym Sym_mod *LSym Sym_modu *LSym Plan9privates *LSym Curp *Prog Printp *Prog Blitrl *Prog Elitrl *Prog Rexflag int Vexflag int Rep int Repn int Lock int Asmode int AsmBuf AsmBuf // instruction buffer for x86 Instoffset int64 Autosize int32 Armsize int32 Pc int64 DiagFunc func(string, ...interface{}) Mode int Cursym *LSym Version int Textp *LSym Etextp *LSym Errors int // state for writing objects Text []*LSym Data []*LSym // contains filtered or unexported fields }
Link holds the context for writing object code from a compiler to be linker input or for reading that input into the linker.
func (*Link) FixedFrameSize ¶
The smallest possible offset from the hardware stack pointer to a local variable on the stack. Architectures that use a link register save its value on the stack in the function prologue and so always have a pointer between the hardware stack pointer and the local variable area.
type LinkArch ¶
type LinkArch struct { *sys.Arch Preprocess func(*Link, *LSym) Assemble func(*Link, *LSym) Follow func(*Link, *LSym) Progedit func(*Link, *Prog) UnaryDst map[As]bool // Instruction takes one operand, a destination. }
LinkArch is the definition of a single architecture.
type Prog ¶
type Prog struct { Ctxt *Link Link *Prog From Addr From3 *Addr // optional To Addr Opt interface{} Forwd *Prog Pcond *Prog Rel *Prog // Source of forward jumps on x86; pcrel on arm Pc int64 Lineno int32 Spadj int32 As As // Assembler opcode. Reg int16 RegTo2 int16 // 2nd register output operand Mark uint16 // bitmask of arch-specific items Optab uint16 Scond uint8 Back uint8 Ft uint8 Tt uint8 Isize uint8 // size of the instruction in bytes (x86 only) Mode int8 Info ProgInfo }
TODO(rsc): Describe prog. TODO(rsc): Describe TEXT/GLOBL flag in from3
func (*Prog) From3Offset ¶
From3Offset returns From3.Offset, or 0 when From3 is nil.
type ProgInfo ¶
type ProgInfo struct { Flags uint32 // flag bits Reguse uint64 // registers implicitly used by this instruction Regset uint64 // registers implicitly set by this instruction Regindex uint64 // registers used by addressing mode // contains filtered or unexported fields }
ProgInfo holds information about the instruction for use by clients such as the compiler. The exact meaning of this data is up to the client and is not interpreted by the cmd/internal/obj/... packages.