Go: cmd/internal/src Index | Files

package src

import "cmd/internal/src"

Index

Package Files

pos.go xpos.go

Constants

const (
    // It is expected that the front end or a phase in SSA will usually generate positions tagged with
    // PosDefaultStmt, but note statement boundaries with PosIsStmt.  Simple statements will have a single
    // boundary; for loops with initialization may have one for their entry and one for their back edge
    // (this depends on exactly how the loop is compiled; the intent is to provide a good experience to a
    // user debugging a program; the goal is that a breakpoint set on the loop line fires both on entry
    // and on iteration).  Proper treatment of non-gofmt input with multiple simple statements on a single
    // line is TBD.
    //
    // Optimizing compilation will move instructions around, and some of these will become known-bad as
    // step targets for debugging purposes (examples: register spills and reloads; code generated into
    // the entry block; invariant code hoisted out of loops) but those instructions will still have interesting
    // positions for profiling purposes. To reflect this these positions will be changed to PosNotStmt.
    //
    // When the optimizer removes an instruction marked PosIsStmt; it should attempt to find a nearby
    // instruction with the same line marked PosDefaultStmt to be the new statement boundary.  I.e., the
    // optimizer should make a best-effort to conserve statement boundary positions, and might be enhanced
    // to note when a statement boundary is not conserved.
    //
    // Code cloning, e.g. loop unrolling or loop unswitching, is an exception to the conservation rule
    // because a user running a debugger would expect to see breakpoints active in the copies of the code.
    //
    // In non-optimizing compilation there is still a role for PosNotStmt because of code generation
    // into the entry block.  PosIsStmt statement positions should be conserved.
    //
    // When code generation occurs any remaining default-marked positions are replaced with not-statement
    // positions.
    //
    PosDefaultStmt uint = iota // Default; position is not a statement boundary, but might be if optimization removes the designated statement boundary
    PosIsStmt                  // Position is a statement bounday; if optimization removes the corresponding instruction, it should attempt to find a new instruction to be the boundary.
    PosNotStmt                 // Position should not be a statement boundary, but line should be preserved for profiling and low-level debugging purposes.
)
const FileSymPrefix = "gofile.."

type Pos Uses

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

A Pos encodes a source position consisting of a (line, column) number pair and a position base. A zero Pos is a ready to use "unknown" position (nil position base and zero line number).

The (line, column) values refer to a position in a file independent of any position base ("absolute" file position).

The position base is used to determine the "relative" position, that is the filename and line number relative to the position base. If the base refers to the current file, there is no difference between absolute and relative positions. If it refers to a //line directive, a relative position is relative to that directive. A position base in turn contains the position at which it was introduced in the current file.

var NoPos Pos

NoPos is a valid unknown position.

func MakePos Uses

func MakePos(base *PosBase, line, col uint) Pos

MakePos creates a new Pos value with the given base, and (file-absolute) line and column.

func (Pos) AbsFilename Uses

func (p Pos) AbsFilename() string

AbsFilename() returns the absolute filename recorded with the position's base.

func (Pos) After Uses

func (p Pos) After(q Pos) bool

After reports whether the position p comes after q in the source. For positions in different files, ordering is by filename.

func (Pos) Base Uses

func (p Pos) Base() *PosBase

Base returns the position base.

func (Pos) Before Uses

func (p Pos) Before(q Pos) bool

Before reports whether the position p comes before q in the source. For positions in different files, ordering is by filename.

func (Pos) Col Uses

func (x Pos) Col() uint

func (Pos) Filename Uses

func (p Pos) Filename() string

Filename returns the name of the actual file containing this position.

func (Pos) Format Uses

func (p Pos) Format(showCol, showOrig bool) string

Format formats a position as "filename:line" or "filename:line:column", controlled by the showCol flag and if the column is known (!= 0). For positions relative to line directives, the original position is shown as well, as in "filename:line[origfile:origline:origcolumn] if showOrig is set.

func (Pos) IsKnown Uses

func (p Pos) IsKnown() bool

IsKnown reports whether the position p is known. A position is known if it either has a non-nil position base, or a non-zero line number.

func (Pos) IsStmt Uses

func (x Pos) IsStmt() uint

func (Pos) Line Uses

func (x Pos) Line() uint

func (Pos) LineNumber Uses

func (p Pos) LineNumber() string

func (Pos) LineNumberHTML Uses

func (p Pos) LineNumberHTML() string

func (Pos) RelCol Uses

func (p Pos) RelCol() uint

RelCol returns the column number relative to the position's base.

func (Pos) RelFilename Uses

func (p Pos) RelFilename() string

RelFilename returns the filename recorded with the position's base.

func (Pos) RelLine Uses

func (p Pos) RelLine() uint

RelLine returns the line number relative to the position's base.

func (*Pos) SetBase Uses

func (p *Pos) SetBase(base *PosBase)

SetBase sets the position base.

func (Pos) String Uses

func (p Pos) String() string

func (Pos) SymFilename Uses

func (p Pos) SymFilename() string

SymFilename() returns the absolute filename recorded with the position's base, prefixed by FileSymPrefix to make it appropriate for use as a linker symbol.

func (Pos) Xlogue Uses

func (x Pos) Xlogue() PosXlogue

type PosBase Uses

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

A PosBase encodes a filename and base position. Typically, each file and line directive introduce a PosBase.

func NewFileBase Uses

func NewFileBase(filename, absFilename string) *PosBase

NewFileBase returns a new *PosBase for a file with the given (relative and absolute) filenames.

func NewInliningBase Uses

func NewInliningBase(old *PosBase, inlTreeIndex int) *PosBase

NewInliningBase returns a copy of the old PosBase with the given inlining index. If old == nil, the resulting PosBase has no filename.

func NewLinePragmaBase Uses

func NewLinePragmaBase(pos Pos, filename, absFilename string, line, col uint) *PosBase

NewLinePragmaBase returns a new *PosBase for a line directive of the form

//line filename:line:col
/*line filename:line:col*/

at position pos.

func (*PosBase) AbsFilename Uses

func (b *PosBase) AbsFilename() string

AbsFilename returns the absolute filename recorded with the base. If b == nil, the result is the empty string.

func (*PosBase) Col Uses

func (b *PosBase) Col() uint

Col returns the column number recorded with the base. If b == nil, the result is 0.

func (*PosBase) Filename Uses

func (b *PosBase) Filename() string

Filename returns the filename recorded with the base. If b == nil, the result is the empty string.

func (*PosBase) InliningIndex Uses

func (b *PosBase) InliningIndex() int

InliningIndex returns the index into the global inlining tree recorded with the base. If b == nil or the base has not been inlined, the result is < 0.

func (*PosBase) Line Uses

func (b *PosBase) Line() uint

Line returns the line number recorded with the base. If b == nil, the result is 0.

func (*PosBase) Pos Uses

func (b *PosBase) Pos() *Pos

Pos returns the position at which base is located. If b == nil, the result is the zero position.

func (*PosBase) SymFilename Uses

func (b *PosBase) SymFilename() string

SymFilename returns the absolute filename recorded with the base, prefixed by FileSymPrefix to make it appropriate for use as a linker symbol. If b is nil, SymFilename returns FileSymPrefix + "??".

type PosTable Uses

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

A PosTable tracks Pos -> XPos conversions and vice versa. Its zero value is a ready-to-use PosTable.

func (*PosTable) Pos Uses

func (t *PosTable) Pos(p XPos) Pos

Pos returns the corresponding Pos for the given p. If p cannot be translated via t, the function panics.

func (*PosTable) XPos Uses

func (t *PosTable) XPos(pos Pos) XPos

XPos returns the corresponding XPos for the given pos, adding pos to t if necessary.

type PosXlogue Uses

type PosXlogue uint
const (
    PosDefaultLogue PosXlogue = iota
    PosPrologueEnd
    PosEpilogueBegin
)

type XPos Uses

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

XPos is a more compact representation of Pos.

var NoXPos XPos

NoXPos is a valid unknown position.

func (XPos) After Uses

func (p XPos) After(q XPos) bool

After reports whether the position p comes after q in the source. For positions with different bases, ordering is by base index.

func (XPos) Before Uses

func (p XPos) Before(q XPos) bool

Before reports whether the position p comes before q in the source. For positions with different bases, ordering is by base index.

func (XPos) Col Uses

func (x XPos) Col() uint

func (XPos) IsKnown Uses

func (p XPos) IsKnown() bool

IsKnown reports whether the position p is known. XPos.IsKnown() matches Pos.IsKnown() for corresponding positions.

func (XPos) IsStmt Uses

func (x XPos) IsStmt() uint

func (XPos) Line Uses

func (x XPos) Line() uint

func (XPos) LineNumber Uses

func (p XPos) LineNumber() string

func (XPos) LineNumberHTML Uses

func (p XPos) LineNumberHTML() string

func (XPos) SameFile Uses

func (p XPos) SameFile(q XPos) bool

SameFile reports whether p and q are positions in the same file.

func (XPos) WithDefaultStmt Uses

func (p XPos) WithDefaultStmt() XPos

WithDefaultStmt returns the same location with undetermined is_stmt

func (XPos) WithIsStmt Uses

func (p XPos) WithIsStmt() XPos

WithIsStmt returns the same location to be marked with DWARF is_stmt=1

func (XPos) WithNotStmt Uses

func (p XPos) WithNotStmt() XPos

WithNotStmt returns the same location to be marked with DWARF is_stmt=0

func (XPos) WithXlogue Uses

func (p XPos) WithXlogue(x PosXlogue) XPos

WithXlogue returns the same location but marked with DWARF function prologue/epilogue

func (XPos) Xlogue Uses

func (x XPos) Xlogue() PosXlogue

Package src imports 2 packages (graph) and is imported by 18 packages. Updated 2019-03-15. Refresh now. Tools for package owners.