From daee726a0b7c932ed418e623ef29697c77d113a8 Mon Sep 17 00:00:00 2001 From: Cherry Zhang Date: Tue, 20 Apr 2021 20:33:43 -0400 Subject: [PATCH] cmd/compile: don't accumulate duplicated named slots Currently, in expand_calls, for each appearance of a named variables's component, we add the named slot to f.Names list. If a variable appears many times, we add it to f.Names many times. Furthure, for each duplicated named slot, its entry in f.NamedValues is a slice that contains all Values associated with that name. This leads to quadratic behavior when iterating named values like for _, name := range f.Names { for _, v := range f.NamedValues[name] { ... } } This CL makes it not to add duplicated entries to f.Names. Change-Id: I82a8d009db81ecf48b4577e0bca501feff677cdf Reviewed-on: https://go-review.googlesource.com/c/go/+/312093 Trust: Cherry Zhang Run-TryBot: Cherry Zhang TryBot-Result: Go Bot Reviewed-by: David Chase Reviewed-by: Than McIntosh --- src/cmd/compile/internal/ssa/expand_calls.go | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/src/cmd/compile/internal/ssa/expand_calls.go b/src/cmd/compile/internal/ssa/expand_calls.go index 46c2388e7b..48e40bb00a 100644 --- a/src/cmd/compile/internal/ssa/expand_calls.go +++ b/src/cmd/compile/internal/ssa/expand_calls.go @@ -1378,9 +1378,11 @@ func expandCalls(f *Func) { // Leaf types may have debug locations if !x.isAlreadyExpandedAggregateType(v.Type) { for _, l := range locs { + if _, ok := f.NamedValues[l]; !ok { + f.Names = append(f.Names, l) + } f.NamedValues[l] = append(f.NamedValues[l], v) } - f.Names = append(f.Names, locs...) continue } // Not-leaf types that had debug locations need to lose them. -- 2.50.0