cmd/compile/internal/ssa: optimize if control flow rule of loong64

goos: linux
goarch: loong64
pkg: cmd/compile/internal/test
cpu: Loongson-3A6000 @ 2500.00MHz
                                 │     old     │                 new                 │
                                 │   sec/op    │   sec/op     vs base                │
Switch8Predictable                 2.908n ± 0%   2.702n ± 2%   -7.10% (p=0.000 n=10)
Switch8Unpredictable               13.29n ± 0%   12.45n ± 0%   -6.32% (p=0.000 n=10)
Switch32Predictable                3.069n ± 0%   3.137n ± 0%   +2.23% (p=0.000 n=10)
Switch32Unpredictable              15.11n ± 0%   13.21n ± 0%  -12.57% (p=0.000 n=10)
SwitchStringPredictable            5.165n ± 0%   4.447n ± 0%  -13.90% (p=0.000 n=10)
SwitchStringUnpredictable          18.26n ± 0%   16.86n ± 0%   -7.67% (p=0.000 n=10)
SwitchTypePredictable              3.961n ± 0%   3.405n ± 0%  -14.04% (p=0.000 n=10)
SwitchTypeUnpredictable            17.92n ± 0%   16.17n ± 0%   -9.77% (p=0.000 n=10)
SwitchInterfaceTypePredictable     8.463n ± 0%   8.492n ± 0%   +0.34% (p=0.001 n=10)
SwitchInterfaceTypeUnpredictable   23.70n ± 0%   22.48n ± 0%   -5.15% (p=0.000 n=10)
geomean                            8.672n        8.018n        -7.54%

Change-Id: Iefbf8e9e784905779f1ebc9fd6a9b7a28cf2f6f4
Reviewed-on: https://go-review.googlesource.com/c/go/+/620815
Reviewed-by: abner chenc <chenguoqi@loongson.cn>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Michael Pratt <mpratt@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>

diff --git a/src/cmd/compile/internal/ssa/_gen/LOONG64.rules b/src/cmd/compile/internal/ssa/_gen/LOONG64.rules
index 64cbe76295c6918e5d7b809b24b43b9f3d5b0c80..923e8ef0e4c3c34b242d3c960e280d60feeec27c 100644 (file)
--- a/src/cmd/compile/internal/ssa/_gen/LOONG64.rules
+++ b/src/cmd/compile/internal/ssa/_gen/LOONG64.rules
@@ -453,6 +453,7 @@
 (GetCallerPC ...) => (LoweredGetCallerPC ...)
 
 (If cond yes no) => (NE (MOVBUreg <typ.UInt64> cond) yes no)
+(MOVBUreg x:(XOR (MOVVconst [1]) ((SGT|SGTU) _ _))) => x
 
 // Write barrier.
 (WB ...) => (LoweredWB ...)

diff --git a/src/cmd/compile/internal/ssa/rewriteLOONG64.go b/src/cmd/compile/internal/ssa/rewriteLOONG64.go
index df5043b949bcf2ecdbee423c8ea7610686ed09a0..abc92b189336630c9c39d70975c02324cc350599 100644 (file)
--- a/src/cmd/compile/internal/ssa/rewriteLOONG64.go
+++ b/src/cmd/compile/internal/ssa/rewriteLOONG64.go
@@ -1907,6 +1907,44 @@ func rewriteValueLOONG64_OpLOONG64MOVBUreg(v *Value) bool {
                v.AddArg(x)
                return true
        }
+       // match: (MOVBUreg x:(XOR (MOVVconst [1]) (SGT _ _)))
+       // result: x
+       for {
+               x := v_0
+               if x.Op != OpLOONG64XOR {
+                       break
+               }
+               _ = x.Args[1]
+               x_0 := x.Args[0]
+               x_1 := x.Args[1]
+               for _i0 := 0; _i0 <= 1; _i0, x_0, x_1 = _i0+1, x_1, x_0 {
+                       if x_0.Op != OpLOONG64MOVVconst || auxIntToInt64(x_0.AuxInt) != 1 || x_1.Op != OpLOONG64SGT {
+                               continue
+                       }
+                       v.copyOf(x)
+                       return true
+               }
+               break
+       }
+       // match: (MOVBUreg x:(XOR (MOVVconst [1]) (SGTU _ _)))
+       // result: x
+       for {
+               x := v_0
+               if x.Op != OpLOONG64XOR {
+                       break
+               }
+               _ = x.Args[1]
+               x_0 := x.Args[0]
+               x_1 := x.Args[1]
+               for _i0 := 0; _i0 <= 1; _i0, x_0, x_1 = _i0+1, x_1, x_0 {
+                       if x_0.Op != OpLOONG64MOVVconst || auxIntToInt64(x_0.AuxInt) != 1 || x_1.Op != OpLOONG64SGTU {
+                               continue
+                       }
+                       v.copyOf(x)
+                       return true
+               }
+               break
+       }
        // match: (MOVBUreg x:(SGT _ _))
        // result: x
        for {