cmd/compile: don't create 2 Sym's and 2 Node's for every string
For every string constant the compiler was creating 2 Sym's and 2
Node's. It would never refer to them again, but would keep them alive
in gostringpkg. This changes the code to just use obj.LSym's instead.
When compiling x/tools/go/types, this yields about a 15% reduction in
the number of calls to newname and a 3% reduction in the total number of
Node objects. Unfortunately I couldn't see any change in compile time,
but reducing memory usage is desirable anyhow.
Passes toolstash -cmp.
Change-Id: I24f1cb1e6cff0a3afba4ca66f7166874917a036b
Reviewed-on: https://go-review.googlesource.com/20792
Reviewed-by: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
diff --git a/src/cmd/compile/internal/gc/ssa.go b/src/cmd/compile/internal/gc/ssa.go
index 716be35..06e317e 100644
--- a/src/cmd/compile/internal/gc/ssa.go
+++ b/src/cmd/compile/internal/gc/ssa.go
@@ -3845,7 +3845,14 @@
switch sym := v.Aux.(type) {
case *ssa.ExternSymbol:
a.Name = obj.NAME_EXTERN
- a.Sym = Linksym(sym.Sym.(*Sym))
+ switch s := sym.Sym.(type) {
+ case *Sym:
+ a.Sym = Linksym(s)
+ case *obj.LSym:
+ a.Sym = s
+ default:
+ v.Fatalf("ExternSymbol.Sym is %T", s)
+ }
case *ssa.ArgSymbol:
n := sym.Node.(*Node)
a.Name = obj.NAME_PARAM
