From 204c618f0a0b175d840bfeb50cb5356deb165f51 Mon Sep 17 00:00:00 2001 From: Than McIntosh Date: Wed, 11 Jul 2018 12:30:05 -0400 Subject: [PATCH] cmd/link: eliminate a couple of unused DWARF attrs The linker's DWARF generation occasionally computes and attaches an attribute X to a type even though the type's abbrev doesn't have the specified attr. For example, the DW_TAG_subroutine_type abbrev entry has no type attribute, but a type attr is given to it (wasting memory). Similarly there are some places where a byte size attr is added to a DIE whose abbrev lacks that attr. This patch trims away a few of these not-needed attrs, saving some very tiny amount of memory. Updates #26186 Change-Id: I69e853df468ac54b07772a614b4106d7c4dae01d Reviewed-on: https://go-review.googlesource.com/123296 Reviewed-by: Heschi Kreinick Run-TryBot: Heschi Kreinick TryBot-Result: Gobot Gobot --- src/cmd/link/internal/ld/dwarf.go | 3 --- 1 file changed, 3 deletions(-) diff --git a/src/cmd/link/internal/ld/dwarf.go b/src/cmd/link/internal/ld/dwarf.go index 830d81d446..ae6f90b079 100644 --- a/src/cmd/link/internal/ld/dwarf.go +++ b/src/cmd/link/internal/ld/dwarf.go @@ -451,7 +451,6 @@ func newtype(ctxt *Link, gotype *sym.Symbol) *dwarf.DWDie { case objabi.KindChan: die = newdie(ctxt, &dwtypes, dwarf.DW_ABRV_CHANTYPE, name, 0) - newattr(die, dwarf.DW_AT_byte_size, dwarf.DW_CLS_CONSTANT, bytesize, 0) s := decodetypeChanElem(ctxt.Arch, gotype) newrefattr(die, dwarf.DW_AT_go_elem, defgotype(ctxt, s)) // Save elem type for synthesizechantypes. We could synthesize here @@ -462,7 +461,6 @@ func newtype(ctxt *Link, gotype *sym.Symbol) *dwarf.DWDie { die = newdie(ctxt, &dwtypes, dwarf.DW_ABRV_FUNCTYPE, name, 0) newattr(die, dwarf.DW_AT_byte_size, dwarf.DW_CLS_CONSTANT, bytesize, 0) dotypedef(ctxt, &dwtypes, name, die) - newrefattr(die, dwarf.DW_AT_type, mustFind(ctxt, "void")) nfields := decodetypeFuncInCount(ctxt.Arch, gotype) for i := 0; i < nfields; i++ { s := decodetypeFuncInType(ctxt.Arch, gotype, i) @@ -483,7 +481,6 @@ func newtype(ctxt *Link, gotype *sym.Symbol) *dwarf.DWDie { case objabi.KindInterface: die = newdie(ctxt, &dwtypes, dwarf.DW_ABRV_IFACETYPE, name, 0) dotypedef(ctxt, &dwtypes, name, die) - newattr(die, dwarf.DW_AT_byte_size, dwarf.DW_CLS_CONSTANT, bytesize, 0) nfields := int(decodetypeIfaceMethodCount(ctxt.Arch, gotype)) var s *sym.Symbol if nfields == 0 { -- 2.50.0