runtime: document implicit fields at the end of _func

Currently these are only implicitly documented by the code that
generates and consumes them. Add explicit documentation.

Change-Id: I25a1294f04dc11785242643bec83370c66ff7a20
Reviewed-on: https://go-review.googlesource.com/c/go/+/427954
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Run-TryBot: Michael Pratt <mpratt@google.com>
This commit is contained in:
Michael Pratt 2022-09-02 10:10:54 -04:00
parent d1681120be
commit e406112011

View file

@ -873,6 +873,28 @@ type _func struct {
flag funcFlag
_ [1]byte // pad
nfuncdata uint8 // must be last, must end on a uint32-aligned boundary
// The end of the struct is followed immediately by two variable-length
// arrays that reference the pcdata and funcdata locations for this
// function.
// pcdata contains the offset into moduledata.pctab for the start of
// that index's table. e.g.,
// &moduledata.pctab[_func.pcdata[_PCDATA_UnsafePoint]] is the start of
// the unsafe point table.
//
// An offset of 0 indicates that there is no table.
//
// pcdata [npcdata]uint32
// funcdata contains the offset past moduledata.gofunc which contains a
// pointer to that index's funcdata. e.g.,
// *(moduledata.gofunc + _func.funcdata[_FUNCDATA_ArgsPointerMaps]) is
// the argument pointer map.
//
// An offset of ^uint32(0) indicates that there is no entry.
//
// funcdata [nfuncdata]uint32
}
// Pseudo-Func that is returned for PCs that occur in inlined code.