From f791b288d1c65420ae6051cdc180e82716952737 Mon Sep 17 00:00:00 2001 From: Josh Bleecher Snyder Date: Thu, 9 Feb 2017 10:45:35 -0800 Subject: [PATCH] cmd/compile: remove some allocs from CSE MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Pick up a few pennies: * CSE gets run twice for each function, but the set of Aux values doesn't change. Avoid populating it twice. * Don't bother populating auxmap for values that can't be CSE'd anyway. name old alloc/op new alloc/op delta Template 41.0MB ± 0% 40.7MB ± 0% -0.61% (p=0.008 n=5+5) Unicode 32.3MB ± 0% 32.3MB ± 0% -0.22% (p=0.008 n=5+5) GoTypes 122MB ± 0% 121MB ± 0% -0.55% (p=0.008 n=5+5) Compiler 482MB ± 0% 479MB ± 0% -0.58% (p=0.008 n=5+5) SSA 865MB ± 0% 862MB ± 0% -0.35% (p=0.008 n=5+5) Flate 26.5MB ± 0% 26.5MB ± 0% ~ (p=0.056 n=5+5) GoParser 32.6MB ± 0% 32.4MB ± 0% -0.58% (p=0.008 n=5+5) Reflect 84.2MB ± 0% 83.8MB ± 0% -0.57% (p=0.008 n=5+5) Tar 27.7MB ± 0% 27.6MB ± 0% -0.37% (p=0.008 n=5+5) XML 44.7MB ± 0% 44.5MB ± 0% -0.53% (p=0.008 n=5+5) name old allocs/op new allocs/op delta Template 373k ± 0% 373k ± 1% ~ (p=1.000 n=5+5) Unicode 326k ± 0% 325k ± 0% ~ (p=0.548 n=5+5) GoTypes 1.16M ± 0% 1.16M ± 0% ~ (p=0.841 n=5+5) Compiler 4.16M ± 0% 4.15M ± 0% ~ (p=0.222 n=5+5) SSA 7.57M ± 0% 7.56M ± 0% -0.22% (p=0.008 n=5+5) Flate 238k ± 1% 239k ± 1% ~ (p=0.690 n=5+5) GoParser 304k ± 0% 304k ± 0% ~ (p=1.000 n=5+5) Reflect 1.01M ± 0% 1.00M ± 0% -0.31% (p=0.016 n=4+5) Tar 245k ± 0% 245k ± 1% ~ (p=0.548 n=5+5) XML 393k ± 0% 391k ± 1% ~ (p=0.095 n=5+5) Change-Id: I78f1ffe129bd8fd590b7511717dd2bf9f5ecbd6d Reviewed-on: https://go-review.googlesource.com/36690 Run-TryBot: Josh Bleecher Snyder TryBot-Result: Gobot Gobot Reviewed-by: Daniel Martí Reviewed-by: Cherry Zhang --- src/cmd/compile/internal/ssa/cse.go | 12 +++++++----- src/cmd/compile/internal/ssa/func.go | 2 ++ 2 files changed, 9 insertions(+), 5 deletions(-) diff --git a/src/cmd/compile/internal/ssa/cse.go b/src/cmd/compile/internal/ssa/cse.go index 39861b6e2a..10f3b883b4 100644 --- a/src/cmd/compile/internal/ssa/cse.go +++ b/src/cmd/compile/internal/ssa/cse.go @@ -30,19 +30,21 @@ func cse(f *Func) { // Make initial coarse partitions by using a subset of the conditions above. a := make([]*Value, 0, f.NumValues()) - auxIDs := auxmap{} + if f.auxmap == nil { + f.auxmap = auxmap{} + } for _, b := range f.Blocks { for _, v := range b.Values { - if auxIDs[v.Aux] == 0 { - auxIDs[v.Aux] = int32(len(auxIDs)) + 1 - } if v.Type.IsMemory() { continue // memory values can never cse } + if f.auxmap[v.Aux] == 0 { + f.auxmap[v.Aux] = int32(len(f.auxmap)) + 1 + } a = append(a, v) } } - partition := partitionValues(a, auxIDs) + partition := partitionValues(a, f.auxmap) // map from value id back to eqclass id valueEqClass := make([]ID, f.NumValues()) diff --git a/src/cmd/compile/internal/ssa/func.go b/src/cmd/compile/internal/ssa/func.go index ea259190da..439e0b0394 100644 --- a/src/cmd/compile/internal/ssa/func.go +++ b/src/cmd/compile/internal/ssa/func.go @@ -43,6 +43,8 @@ type Func struct { cachedSdom SparseTree // cached dominator tree cachedLoopnest *loopnest // cached loop nest information + auxmap auxmap // map from aux values to opaque ids used by CSE + constants map[int64][]*Value // constants cache, keyed by constant value; users must check value's Op and Type }