From 7aa6e0faf20d48956eaeead4a71992dd53306c19 Mon Sep 17 00:00:00 2001 From: Cherry Zhang Date: Thu, 30 Apr 2020 17:45:00 -0400 Subject: [PATCH] [dev.link] cmd/link: drop fields of external symbols after LoadFull MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Free some memory. Linking cmd/compile with external linking, name old live-B new live-B delta Loadlibfull_GC 55.3M ± 0% 52.2M ± 0% -5.50% (p=0.008 n=5+5) Change-Id: Ib8de2e61f2b012efaf6bdd98f9e5c56a19910b47 Reviewed-on: https://go-review.googlesource.com/c/go/+/231224 Reviewed-by: Jeremy Faller Reviewed-by: Than McIntosh --- src/cmd/link/internal/loader/loader.go | 24 ++++++++++++++++++------ 1 file changed, 18 insertions(+), 6 deletions(-) diff --git a/src/cmd/link/internal/loader/loader.go b/src/cmd/link/internal/loader/loader.go index e1d5c864ab..f4d91644c9 100644 --- a/src/cmd/link/internal/loader/loader.go +++ b/src/cmd/link/internal/loader/loader.go @@ -2128,12 +2128,14 @@ func (l *Loader) LoadFull(arch *sys.Arch, syms *sym.Symbols, needReloc bool) { // Resolve ABI aliases for external symbols. This is only // needed for internal cgo linking. - for _, i := range l.extReader.syms { - if s := l.Syms[i]; s != nil && s.Attr.Reachable() { - for ri := range s.R { - r := &s.R[ri] - if r.Sym != nil && r.Sym.Type == sym.SABIALIAS { - r.Sym = r.Sym.R[0].Sym + if needReloc { + for _, i := range l.extReader.syms { + if s := l.Syms[i]; s != nil && s.Attr.Reachable() { + for ri := range s.R { + r := &s.R[ri] + if r.Sym != nil && r.Sym.Type == sym.SABIALIAS { + r.Sym = r.Sym.R[0].Sym + } } } } @@ -2170,6 +2172,16 @@ func (l *Loader) LoadFull(arch *sys.Arch, syms *sym.Symbols, needReloc bool) { l.dynid = nil l.relocVariant = nil l.extRelocs = nil + + // Drop fields that are no longer needed. + for _, i := range l.extReader.syms { + pp := l.getPayload(i) + pp.name = "" + pp.relocs = nil + pp.reltypes = nil + pp.auxs = nil + pp.data = nil + } } // ResolveABIAlias given a symbol returns the ABI alias target of that -- 2.50.0