diff options
Diffstat (limited to 'libgo/go/runtime/symtab.go')
| -rw-r--r-- | libgo/go/runtime/symtab.go | 38 |
1 files changed, 27 insertions, 11 deletions
diff --git a/libgo/go/runtime/symtab.go b/libgo/go/runtime/symtab.go index bad0347..3d15fc8 100644 --- a/libgo/go/runtime/symtab.go +++ b/libgo/go/runtime/symtab.go @@ -7,6 +7,7 @@ package runtime // Frames may be used to get function/file/line information for a // slice of PC values returned by Callers. type Frames struct { + // callers is a slice of PCs that have not yet been expanded. callers []uintptr // The last PC we saw. @@ -18,23 +19,34 @@ type Frames struct { // Frame is the information returned by Frames for each call frame. type Frame struct { - // Program counter for this frame; multiple frames may have - // the same PC value. + // PC is the program counter for the location in this frame. + // For a frame that calls another frame, this will be the + // program counter of a call instruction. Because of inlining, + // multiple frames may have the same PC value, but different + // symbolic information. PC uintptr - // Func for this frame; may be nil for non-Go code or fully - // inlined functions. + // Func is the Func value of this call frame. This may be nil + // for non-Go code or fully inlined functions. Func *Func - // Function name, file name, and line number for this call frame. - // May be the empty string or zero if not known. + // Function is the package path-qualified function name of + // this call frame. If non-empty, this string uniquely + // identifies a single function in the program. + // This may be the empty string if not known. // If Func is not nil then Function == Func.Name(). Function string - File string - Line int - // Entry point for the function; may be zero if not known. - // If Func is not nil then Entry == Func.Entry(). + // File and Line are the file name and line number of the + // location in this frame. For non-leaf frames, this will be + // the location of a call. These may be the empty string and + // zero, respectively, if not known. + File string + Line int + + // Entry point program counter for the function; may be zero + // if not known. If Func is not nil then Entry == + // Func.Entry(). Entry uintptr } @@ -94,7 +106,8 @@ func (ci *Frames) Next() (frame Frame, more bool) { // NOTE: Func does not expose the actual unexported fields, because we return *Func // values to users, and we want to keep them from being able to overwrite the data // with (say) *f = Func{}. -// All code operating on a *Func must call raw to get the *_func instead. +// All code operating on a *Func must call raw() to get the *_func +// or funcInfo() to get the funcInfo instead. // A Func represents a Go function in the running binary. type Func struct { @@ -104,6 +117,9 @@ type Func struct { // FuncForPC returns a *Func describing the function that contains the // given program counter address, or else nil. +// +// If pc represents multiple functions because of inlining, it returns +// the *Func describing the outermost function. func FuncForPC(pc uintptr) *Func { name, _, _ := funcfileline(pc, -1) if name == "" { |