cmd/compile: remove loopbce pass

prove now is able to do what loopbce used to do.

Passes toolstash -cmp.

Compilebench of the whole serie (master 9967582f77):

name       old time/op     new time/op     delta
Template       208ms ±18%      198ms ± 4%    ~     (p=0.690 n=5+5)
Unicode       99.1ms ±19%     96.5ms ± 4%    ~     (p=0.548 n=5+5)
GoTypes        623ms ± 1%      633ms ± 1%    ~     (p=0.056 n=5+5)
Compiler       2.94s ± 2%      3.02s ± 4%    ~     (p=0.095 n=5+5)
SSA            6.77s ± 1%      7.11s ± 2%  +4.94%  (p=0.008 n=5+5)
Flate          129ms ± 1%      136ms ± 0%  +4.87%  (p=0.016 n=5+4)
GoParser       152ms ± 3%      156ms ± 1%    ~     (p=0.095 n=5+5)
Reflect        380ms ± 2%      392ms ± 1%  +3.30%  (p=0.008 n=5+5)
Tar            185ms ± 6%      184ms ± 2%    ~     (p=0.690 n=5+5)
XML            223ms ± 2%      228ms ± 3%    ~     (p=0.095 n=5+5)
StdCmd         26.8s ± 2%      28.0s ± 5%  +4.46%  (p=0.032 n=5+5)

name       old user-ns/op  new user-ns/op  delta
Template        252M ± 5%       248M ± 3%    ~     (p=1.000 n=5+5)
Unicode         118M ± 7%       121M ± 4%    ~     (p=0.548 n=5+5)
GoTypes         790M ± 2%       793M ± 2%    ~     (p=0.690 n=5+5)
Compiler       3.78G ± 3%      3.91G ± 4%    ~     (p=0.056 n=5+5)
SSA            8.98G ± 2%      9.52G ± 3%  +6.08%  (p=0.008 n=5+5)
Flate           155M ± 1%       160M ± 0%  +3.47%  (p=0.016 n=5+4)
GoParser        185M ± 4%       187M ± 2%    ~     (p=0.310 n=5+5)
Reflect         469M ± 1%       481M ± 1%  +2.52%  (p=0.016 n=5+5)
Tar             222M ± 4%       222M ± 2%    ~     (p=0.841 n=5+5)
XML             269M ± 1%       274M ± 2%  +1.88%  (p=0.032 n=5+5)

name       old text-bytes  new text-bytes  delta
HelloSize       664k ± 0%       664k ± 0%    ~     (all equal)
CmdGoSize      7.23M ± 0%      7.22M ± 0%  -0.06%  (p=0.008 n=5+5)

name       old data-bytes  new data-bytes  delta
HelloSize       134k ± 0%       134k ± 0%    ~     (all equal)
CmdGoSize       390k ± 0%       390k ± 0%    ~     (all equal)

name       old exe-bytes   new exe-bytes   delta
HelloSize      1.39M ± 0%      1.39M ± 0%    ~     (all equal)
CmdGoSize      14.4M ± 0%      14.4M ± 0%  -0.06%  (p=0.008 n=5+5)

Go1 of the whole serie:

name                      old time/op    new time/op    delta
BinaryTree17-16              5.40s ± 6%     5.38s ± 4%     ~     (p=1.000 n=12+10)
Fannkuch11-16                4.04s ± 3%     3.81s ± 3%   -5.70%  (p=0.000 n=11+11)
FmtFprintfEmpty-16          60.7ns ± 2%    60.2ns ± 3%     ~     (p=0.136 n=11+10)
FmtFprintfString-16          115ns ± 2%     114ns ± 4%     ~     (p=0.175 n=11+10)
FmtFprintfInt-16             118ns ± 2%     125ns ± 2%   +5.76%  (p=0.000 n=11+10)
FmtFprintfIntInt-16          196ns ± 2%     204ns ± 3%   +4.42%  (p=0.000 n=10+11)
FmtFprintfPrefixedInt-16     207ns ± 2%     214ns ± 2%   +3.23%  (p=0.000 n=10+11)
FmtFprintfFloat-16           364ns ± 3%     357ns ± 2%   -1.88%  (p=0.002 n=11+11)
FmtManyArgs-16               773ns ± 2%     775ns ± 1%     ~     (p=0.457 n=11+10)
GobDecode-16                11.2ms ± 4%    11.0ms ± 3%   -1.51%  (p=0.022 n=10+9)
GobEncode-16                9.91ms ± 6%    9.81ms ± 5%     ~     (p=0.699 n=11+11)
Gzip-16                      339ms ± 1%     338ms ± 1%     ~     (p=0.438 n=11+11)
Gunzip-16                   64.4ms ± 1%    65.2ms ± 1%   +1.28%  (p=0.001 n=10+11)
HTTPClientServer-16          157µs ± 7%     160µs ± 5%     ~     (p=0.133 n=11+11)
JSONEncode-16               22.3ms ± 4%    23.2ms ± 4%   +3.79%  (p=0.000 n=11+11)
JSONDecode-16               96.7ms ± 3%    96.6ms ± 1%     ~     (p=0.562 n=11+11)
Mandelbrot200-16            6.42ms ± 1%    6.40ms ± 1%     ~     (p=0.365 n=11+11)
GoParse-16                  5.59ms ± 7%    5.42ms ± 5%   -3.07%  (p=0.020 n=11+10)
RegexpMatchEasy0_32-16       113ns ± 2%     113ns ± 3%     ~     (p=0.968 n=11+10)
RegexpMatchEasy0_1K-16       417ns ± 1%     416ns ± 3%     ~     (p=0.742 n=11+10)
RegexpMatchEasy1_32-16       106ns ± 1%     107ns ± 3%     ~     (p=0.223 n=11+11)
RegexpMatchEasy1_1K-16       654ns ± 2%     657ns ± 1%     ~     (p=0.672 n=11+8)
RegexpMatchMedium_32-16      176ns ± 3%     177ns ± 1%     ~     (p=0.664 n=11+9)
RegexpMatchMedium_1K-16     56.3µs ± 3%    56.7µs ± 3%     ~     (p=0.171 n=11+11)
RegexpMatchHard_32-16       2.83µs ± 5%    2.83µs ± 4%     ~     (p=0.735 n=11+11)
RegexpMatchHard_1K-16       82.7µs ± 2%    82.7µs ± 2%     ~     (p=0.853 n=10+10)
Revcomp-16                   679ms ± 9%     782ms ±29%  +15.16%  (p=0.031 n=9+11)
Template-16                  118ms ± 1%     109ms ± 2%   -7.49%  (p=0.000 n=11+11)
TimeParse-16                 474ns ± 1%     462ns ± 1%   -2.59%  (p=0.000 n=11+11)
TimeFormat-16                482ns ± 1%     494ns ± 1%   +2.49%  (p=0.000 n=10+11)

name                      old speed      new speed      delta
GobDecode-16              68.7MB/s ± 4%  69.8MB/s ± 3%   +1.52%  (p=0.022 n=10+9)
GobEncode-16              77.6MB/s ± 6%  78.3MB/s ± 5%     ~     (p=0.699 n=11+11)
Gzip-16                   57.2MB/s ± 1%  57.3MB/s ± 1%     ~     (p=0.428 n=11+11)
Gunzip-16                  301MB/s ± 2%   298MB/s ± 1%   -1.07%  (p=0.007 n=11+11)
JSONEncode-16             86.9MB/s ± 4%  83.7MB/s ± 4%   -3.63%  (p=0.000 n=11+11)
JSONDecode-16             20.1MB/s ± 3%  20.1MB/s ± 1%     ~     (p=0.529 n=11+11)
GoParse-16                10.4MB/s ± 6%  10.7MB/s ± 4%   +3.12%  (p=0.020 n=11+10)
RegexpMatchEasy0_32-16     282MB/s ± 2%   282MB/s ± 3%     ~     (p=0.756 n=11+10)
RegexpMatchEasy0_1K-16    2.45GB/s ± 1%  2.46GB/s ± 2%     ~     (p=0.705 n=11+10)
RegexpMatchEasy1_32-16     299MB/s ± 1%   297MB/s ± 2%     ~     (p=0.151 n=11+11)
RegexpMatchEasy1_1K-16    1.56GB/s ± 2%  1.56GB/s ± 1%     ~     (p=0.717 n=11+8)
RegexpMatchMedium_32-16   5.67MB/s ± 4%  5.63MB/s ± 1%     ~     (p=0.538 n=11+9)
RegexpMatchMedium_1K-16   18.2MB/s ± 3%  18.1MB/s ± 3%     ~     (p=0.156 n=11+11)
RegexpMatchHard_32-16     11.3MB/s ± 5%  11.3MB/s ± 4%     ~     (p=0.711 n=11+11)
RegexpMatchHard_1K-16     12.4MB/s ± 1%  12.4MB/s ± 2%     ~     (p=0.535 n=9+10)
Revcomp-16                 370MB/s ± 5%   332MB/s ±24%     ~     (p=0.062 n=8+11)
Template-16               16.5MB/s ± 1%  17.8MB/s ± 2%   +8.11%  (p=0.000 n=11+11)

Change-Id: I41e46f375ee127785c6491f7ef5bd35581261ae6
Reviewed-on: https://go-review.googlesource.com/104039
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
This commit is contained in:
Giovanni Bajo 2018-04-02 01:27:01 +02:00
parent 7ec25d0acf
commit f49369b67c
2 changed files with 0 additions and 132 deletions

View file

@ -342,7 +342,6 @@ var passes = [...]pass{
{name: "phiopt", fn: phiopt},
{name: "nilcheckelim", fn: nilcheckelim},
{name: "prove", fn: prove},
{name: "loopbce", fn: loopbce},
{name: "decompose builtin", fn: decomposeBuiltIn, required: true},
{name: "softfloat", fn: softfloat, required: true},
{name: "late opt", fn: opt, required: true}, // TODO: split required rules and optimizing rules

View file

@ -159,127 +159,6 @@ nextb:
return iv
}
// loopbce performs loop based bounds check elimination.
func loopbce(f *Func) {
ivList := findIndVar(f)
m := make(map[*Value]indVar)
for _, iv := range ivList {
m[iv.ind] = iv
}
removeBoundsChecks(f, m)
}
// removesBoundsChecks remove IsInBounds and IsSliceInBounds based on the induction variables.
func removeBoundsChecks(f *Func, m map[*Value]indVar) {
sdom := f.sdom()
for _, b := range f.Blocks {
if b.Kind != BlockIf {
continue
}
v := b.Control
// Simplify:
// (IsInBounds ind max) where 0 <= const == min <= ind < max.
// (IsSliceInBounds ind max) where 0 <= const == min <= ind < max.
// Found in:
// for i := range a {
// use a[i]
// use a[i:]
// use a[:i]
// }
if v.Op == OpIsInBounds || v.Op == OpIsSliceInBounds {
ind, add := dropAdd64(v.Args[0])
if ind.Op != OpPhi {
goto skip1
}
if v.Op == OpIsInBounds && add != 0 {
goto skip1
}
if v.Op == OpIsSliceInBounds && (0 > add || add > 1) {
goto skip1
}
if iv, has := m[ind]; has && sdom.isAncestorEq(iv.entry, b) && isNonNegative(iv.min) {
if v.Args[1] == iv.max {
if f.pass.debug > 0 {
f.Warnl(b.Pos, "Found redundant %s", v.Op)
}
goto simplify
}
}
}
skip1:
// Simplify:
// (IsSliceInBounds ind (SliceCap a)) where 0 <= min <= ind < max == (SliceLen a)
// Found in:
// for i := range a {
// use a[:i]
// use a[:i+1]
// }
if v.Op == OpIsSliceInBounds {
ind, add := dropAdd64(v.Args[0])
if ind.Op != OpPhi {
goto skip2
}
if 0 > add || add > 1 {
goto skip2
}
if iv, has := m[ind]; has && sdom.isAncestorEq(iv.entry, b) && isNonNegative(iv.min) {
if v.Args[1].Op == OpSliceCap && iv.max.Op == OpSliceLen && v.Args[1].Args[0] == iv.max.Args[0] {
if f.pass.debug > 0 {
f.Warnl(b.Pos, "Found redundant %s (len promoted to cap)", v.Op)
}
goto simplify
}
}
}
skip2:
// Simplify
// (IsInBounds (Add64 ind) (Const64 [c])) where 0 <= min <= ind < max <= (Const64 [c])
// (IsSliceInBounds ind (Const64 [c])) where 0 <= min <= ind < max <= (Const64 [c])
if v.Op == OpIsInBounds || v.Op == OpIsSliceInBounds {
ind, add := dropAdd64(v.Args[0])
if ind.Op != OpPhi {
goto skip3
}
// ind + add >= 0 <-> min + add >= 0 <-> min >= -add
if iv, has := m[ind]; has && sdom.isAncestorEq(iv.entry, b) && isGreaterOrEqualThan(iv.min, -add) {
if !v.Args[1].isGenericIntConst() || !iv.max.isGenericIntConst() {
goto skip3
}
limit := v.Args[1].AuxInt
if v.Op == OpIsSliceInBounds {
// If limit++ overflows signed integer then 0 <= max && max <= limit will be false.
limit++
}
if max := iv.max.AuxInt + add; 0 <= max && max <= limit { // handle overflow
if f.pass.debug > 0 {
f.Warnl(b.Pos, "Found redundant (%s ind %d), ind < %d", v.Op, v.Args[1].AuxInt, iv.max.AuxInt+add)
}
goto simplify
}
}
}
skip3:
continue
simplify:
f.Logf("removing bounds check %v at %v in %s\n", b.Control, b, f.Name)
b.Kind = BlockFirst
b.SetControl(nil)
}
}
func dropAdd64(v *Value) (*Value, int64) {
if v.Op == OpAdd64 && v.Args[0].Op == OpConst64 {
return v.Args[1], v.Args[0].AuxInt
@ -289,13 +168,3 @@ func dropAdd64(v *Value) (*Value, int64) {
}
return v, 0
}
func isGreaterOrEqualThan(v *Value, c int64) bool {
if c == 0 {
return isNonNegative(v)
}
if v.isGenericIntConst() && v.AuxInt >= c {
return true
}
return false
}