cmd/compile: reduce amount of code generated for block rewrite rules

Add a Reset method to blocks that allows us to reduce the amount of
code we generate for block rewrite rules.

Thanks to Cherry for suggesting a similar fix to this in CL 196557.

Compilebench result:

name                      old time/op       new time/op       delta
Template                        211ms ± 1%        211ms ± 1%   -0.30%  (p=0.028 n=19+20)
Unicode                        83.7ms ± 3%       83.0ms ± 2%   -0.79%  (p=0.029 n=18+19)
GoTypes                         757ms ± 1%        755ms ± 1%   -0.31%  (p=0.034 n=19+19)
Compiler                        3.51s ± 1%        3.50s ± 1%   -0.20%  (p=0.013 n=18+18)
SSA                             11.7s ± 1%        11.7s ± 1%   -0.38%  (p=0.000 n=19+19)
Flate                           131ms ± 1%        130ms ± 1%   -0.32%  (p=0.024 n=18+18)
GoParser                        162ms ± 1%        162ms ± 1%     ~     (p=0.059 n=20+18)
Reflect                         471ms ± 0%        470ms ± 0%   -0.24%  (p=0.045 n=20+17)
Tar                             187ms ± 1%        186ms ± 1%     ~     (p=0.157 n=20+20)
XML                             255ms ± 1%        255ms ± 1%     ~     (p=0.461 n=19+20)
LinkCompiler                    754ms ± 2%        755ms ± 2%     ~     (p=0.919 n=17+17)
ExternalLinkCompiler            2.82s ±16%        2.37s ±10%  -15.94%  (p=0.000 n=20+20)
LinkWithoutDebugCompiler        439ms ± 4%        442ms ± 6%     ~     (p=0.461 n=18+19)
StdCmd                          25.8s ± 2%        25.5s ± 1%   -0.95%  (p=0.000 n=20+20)

name                      old user-time/op  new user-time/op  delta
Template                        240ms ± 8%        238ms ± 7%     ~     (p=0.301 n=20+20)
Unicode                         107ms ±18%        104ms ±13%     ~     (p=0.149 n=20+20)
GoTypes                         883ms ± 3%        888ms ± 2%     ~     (p=0.211 n=20+20)
Compiler                        4.22s ± 1%        4.20s ± 1%     ~     (p=0.077 n=20+18)
SSA                             14.1s ± 1%        14.1s ± 2%     ~     (p=0.192 n=20+20)
Flate                           145ms ±10%        148ms ± 5%     ~     (p=0.126 n=20+18)
GoParser                        186ms ± 7%        186ms ± 7%     ~     (p=0.779 n=20+20)
Reflect                         538ms ± 3%        541ms ± 3%     ~     (p=0.192 n=20+20)
Tar                             218ms ± 4%        217ms ± 6%     ~     (p=0.835 n=19+20)
XML                             298ms ± 5%        298ms ± 5%     ~     (p=0.749 n=19+20)
LinkCompiler                    818ms ± 5%        825ms ± 8%     ~     (p=0.461 n=20+20)
ExternalLinkCompiler            1.55s ± 4%        1.53s ± 5%     ~     (p=0.063 n=20+18)
LinkWithoutDebugCompiler        460ms ±12%        460ms ± 7%     ~     (p=0.925 n=20+20)

name                      old object-bytes  new object-bytes  delta
Template                        554kB ± 0%        554kB ± 0%     ~     (all equal)
Unicode                         215kB ± 0%        215kB ± 0%     ~     (all equal)
GoTypes                        2.01MB ± 0%       2.01MB ± 0%     ~     (all equal)
Compiler                       7.97MB ± 0%       7.97MB ± 0%   +0.00%  (p=0.000 n=20+20)
SSA                            26.8MB ± 0%       26.9MB ± 0%   +0.27%  (p=0.000 n=20+20)
Flate                           340kB ± 0%        340kB ± 0%     ~     (all equal)
GoParser                        434kB ± 0%        434kB ± 0%     ~     (all equal)
Reflect                        1.34MB ± 0%       1.34MB ± 0%     ~     (all equal)
Tar                             480kB ± 0%        480kB ± 0%     ~     (all equal)
XML                             622kB ± 0%        622kB ± 0%     ~     (all equal)

name                      old export-bytes  new export-bytes  delta
Template                       20.4kB ± 0%       20.4kB ± 0%     ~     (all equal)
Unicode                        8.21kB ± 0%       8.21kB ± 0%     ~     (all equal)
GoTypes                        36.6kB ± 0%       36.6kB ± 0%     ~     (all equal)
Compiler                        115kB ± 0%        115kB ± 0%   +0.08%  (p=0.000 n=20+20)
SSA                             141kB ± 0%        141kB ± 0%   +0.07%  (p=0.000 n=20+20)
Flate                          5.11kB ± 0%       5.11kB ± 0%     ~     (all equal)
GoParser                       8.93kB ± 0%       8.93kB ± 0%     ~     (all equal)
Reflect                        11.8kB ± 0%       11.8kB ± 0%     ~     (all equal)
Tar                            10.9kB ± 0%       10.9kB ± 0%     ~     (all equal)
XML                            17.4kB ± 0%       17.4kB ± 0%     ~     (all equal)

name                      old text-bytes    new text-bytes    delta
HelloSize                       742kB ± 0%        742kB ± 0%     ~     (all equal)
CmdGoSize                      10.7MB ± 0%       10.7MB ± 0%     ~     (all equal)

name                      old data-bytes    new data-bytes    delta
HelloSize                      10.7kB ± 0%       10.7kB ± 0%     ~     (all equal)
CmdGoSize                       312kB ± 0%        312kB ± 0%     ~     (all equal)

name                      old bss-bytes     new bss-bytes     delta
HelloSize                       122kB ± 0%        122kB ± 0%     ~     (all equal)
CmdGoSize                       146kB ± 0%        146kB ± 0%     ~     (all equal)

name                      old exe-bytes     new exe-bytes     delta
HelloSize                      1.10MB ± 0%       1.10MB ± 0%     ~     (all equal)
CmdGoSize                      14.9MB ± 0%       14.9MB ± 0%     ~     (all equal)

Change-Id: Ic89a8e62423b3d9fd9391159e0663acf450803b5
Reviewed-on: https://go-review.googlesource.com/c/go/+/198419
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>

1 files changed, 33 insertions, 99 deletions

diff --git a/src/cmd/compile/internal/ssa/rewriteMIPS64.go b/src/cmd/compile/internal/ssa/rewriteMIPS64.go
index 226dc00952..c9cc5ce4f9 100644
--- a/src/cmd/compile/internal/ssa/rewriteMIPS64.go
+++ b/src/cmd/compile/internal/ssa/rewriteMIPS64.go
@@ -9747,10 +9747,8 @@ func rewriteBlockMIPS64(b *Block) bool {
 		for b.Controls[0].Op == OpMIPS64FPFlagTrue {
 			v_0 := b.Controls[0]
 			cmp := v_0.Args[0]
-			b.Kind = BlockMIPS64FPF
-			b.ResetControls()
+			b.Reset(BlockMIPS64FPF)
 			b.AddControl(cmp)
-			b.Aux = nil
 			return true
 		}
 		// match: (EQ (FPFlagFalse cmp) yes no)
@@ -9758,10 +9756,8 @@ func rewriteBlockMIPS64(b *Block) bool {
 		for b.Controls[0].Op == OpMIPS64FPFlagFalse {
 			v_0 := b.Controls[0]
 			cmp := v_0.Args[0]
-			b.Kind = BlockMIPS64FPT
-			b.ResetControls()
+			b.Reset(BlockMIPS64FPT)
 			b.AddControl(cmp)
-			b.Aux = nil
 			return true
 		}
 		// match: (EQ (XORconst [1] cmp:(SGT _ _)) yes no)
@@ -9776,10 +9772,8 @@ func rewriteBlockMIPS64(b *Block) bool {
 				break
 			}
 			_ = cmp.Args[1]
-			b.Kind = BlockMIPS64NE
-			b.ResetControls()
+			b.Reset(BlockMIPS64NE)
 			b.AddControl(cmp)
-			b.Aux = nil
 			return true
 		}
 		// match: (EQ (XORconst [1] cmp:(SGTU _ _)) yes no)
@@ -9794,10 +9788,8 @@ func rewriteBlockMIPS64(b *Block) bool {
 				break
 			}
 			_ = cmp.Args[1]
-			b.Kind = BlockMIPS64NE
-			b.ResetControls()
+			b.Reset(BlockMIPS64NE)
 			b.AddControl(cmp)
-			b.Aux = nil
 			return true
 		}
 		// match: (EQ (XORconst [1] cmp:(SGTconst _)) yes no)
@@ -9811,10 +9803,8 @@ func rewriteBlockMIPS64(b *Block) bool {
 			if cmp.Op != OpMIPS64SGTconst {
 				break
 			}
-			b.Kind = BlockMIPS64NE
-			b.ResetControls()
+			b.Reset(BlockMIPS64NE)
 			b.AddControl(cmp)
-			b.Aux = nil
 			return true
 		}
 		// match: (EQ (XORconst [1] cmp:(SGTUconst _)) yes no)
@@ -9828,10 +9818,8 @@ func rewriteBlockMIPS64(b *Block) bool {
 			if cmp.Op != OpMIPS64SGTUconst {
 				break
 			}
-			b.Kind = BlockMIPS64NE
-			b.ResetControls()
+			b.Reset(BlockMIPS64NE)
 			b.AddControl(cmp)
-			b.Aux = nil
 			return true
 		}
 		// match: (EQ (SGTUconst [1] x) yes no)
@@ -9842,10 +9830,8 @@ func rewriteBlockMIPS64(b *Block) bool {
 				break
 			}
 			x := v_0.Args[0]
-			b.Kind = BlockMIPS64NE
-			b.ResetControls()
+			b.Reset(BlockMIPS64NE)
 			b.AddControl(x)
-			b.Aux = nil
 			return true
 		}
 		// match: (EQ (SGTU x (MOVVconst [0])) yes no)
@@ -9858,10 +9844,8 @@ func rewriteBlockMIPS64(b *Block) bool {
 			if v_0_1.Op != OpMIPS64MOVVconst || v_0_1.AuxInt != 0 {
 				break
 			}
-			b.Kind = BlockMIPS64EQ
-			b.ResetControls()
+			b.Reset(BlockMIPS64EQ)
 			b.AddControl(x)
-			b.Aux = nil
 			return true
 		}
 		// match: (EQ (SGTconst [0] x) yes no)
@@ -9872,10 +9856,8 @@ func rewriteBlockMIPS64(b *Block) bool {
 				break
 			}
 			x := v_0.Args[0]
-			b.Kind = BlockMIPS64GEZ
-			b.ResetControls()
+			b.Reset(BlockMIPS64GEZ)
 			b.AddControl(x)
-			b.Aux = nil
 			return true
 		}
 		// match: (EQ (SGT x (MOVVconst [0])) yes no)
@@ -9888,10 +9870,8 @@ func rewriteBlockMIPS64(b *Block) bool {
 			if v_0_1.Op != OpMIPS64MOVVconst || v_0_1.AuxInt != 0 {
 				break
 			}
-			b.Kind = BlockMIPS64LEZ
-			b.ResetControls()
+			b.Reset(BlockMIPS64LEZ)
 			b.AddControl(x)
-			b.Aux = nil
 			return true
 		}
 		// match: (EQ (MOVVconst [0]) yes no)
@@ -9901,9 +9881,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 			if v_0.AuxInt != 0 {
 				break
 			}
-			b.Kind = BlockFirst
-			b.ResetControls()
-			b.Aux = nil
+			b.Reset(BlockFirst)
 			return true
 		}
 		// match: (EQ (MOVVconst [c]) yes no)
@@ -9915,9 +9893,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 			if !(c != 0) {
 				break
 			}
-			b.Kind = BlockFirst
-			b.ResetControls()
-			b.Aux = nil
+			b.Reset(BlockFirst)
 			b.swapSuccessors()
 			return true
 		}
@@ -9931,9 +9907,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 			if !(c >= 0) {
 				break
 			}
-			b.Kind = BlockFirst
-			b.ResetControls()
-			b.Aux = nil
+			b.Reset(BlockFirst)
 			return true
 		}
 		// match: (GEZ (MOVVconst [c]) yes no)
@@ -9945,9 +9919,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 			if !(c < 0) {
 				break
 			}
-			b.Kind = BlockFirst
-			b.ResetControls()
-			b.Aux = nil
+			b.Reset(BlockFirst)
 			b.swapSuccessors()
 			return true
 		}
@@ -9961,9 +9933,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 			if !(c > 0) {
 				break
 			}
-			b.Kind = BlockFirst
-			b.ResetControls()
-			b.Aux = nil
+			b.Reset(BlockFirst)
 			return true
 		}
 		// match: (GTZ (MOVVconst [c]) yes no)
@@ -9975,9 +9945,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 			if !(c <= 0) {
 				break
 			}
-			b.Kind = BlockFirst
-			b.ResetControls()
-			b.Aux = nil
+			b.Reset(BlockFirst)
 			b.swapSuccessors()
 			return true
 		}
@@ -9986,10 +9954,8 @@ func rewriteBlockMIPS64(b *Block) bool {
 		// result: (NE cond yes no)
 		for {
 			cond := b.Controls[0]
-			b.Kind = BlockMIPS64NE
-			b.ResetControls()
+			b.Reset(BlockMIPS64NE)
 			b.AddControl(cond)
-			b.Aux = nil
 			return true
 		}
 	case BlockMIPS64LEZ:
@@ -10002,9 +9968,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 			if !(c <= 0) {
 				break
 			}
-			b.Kind = BlockFirst
-			b.ResetControls()
-			b.Aux = nil
+			b.Reset(BlockFirst)
 			return true
 		}
 		// match: (LEZ (MOVVconst [c]) yes no)
@@ -10016,9 +9980,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 			if !(c > 0) {
 				break
 			}
-			b.Kind = BlockFirst
-			b.ResetControls()
-			b.Aux = nil
+			b.Reset(BlockFirst)
 			b.swapSuccessors()
 			return true
 		}
@@ -10032,9 +9994,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 			if !(c < 0) {
 				break
 			}
-			b.Kind = BlockFirst
-			b.ResetControls()
-			b.Aux = nil
+			b.Reset(BlockFirst)
 			return true
 		}
 		// match: (LTZ (MOVVconst [c]) yes no)
@@ -10046,9 +10006,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 			if !(c >= 0) {
 				break
 			}
-			b.Kind = BlockFirst
-			b.ResetControls()
-			b.Aux = nil
+			b.Reset(BlockFirst)
 			b.swapSuccessors()
 			return true
 		}
@@ -10058,10 +10016,8 @@ func rewriteBlockMIPS64(b *Block) bool {
 		for b.Controls[0].Op == OpMIPS64FPFlagTrue {
 			v_0 := b.Controls[0]
 			cmp := v_0.Args[0]
-			b.Kind = BlockMIPS64FPT
-			b.ResetControls()
+			b.Reset(BlockMIPS64FPT)
 			b.AddControl(cmp)
-			b.Aux = nil
 			return true
 		}
 		// match: (NE (FPFlagFalse cmp) yes no)
@@ -10069,10 +10025,8 @@ func rewriteBlockMIPS64(b *Block) bool {
 		for b.Controls[0].Op == OpMIPS64FPFlagFalse {
 			v_0 := b.Controls[0]
 			cmp := v_0.Args[0]
-			b.Kind = BlockMIPS64FPF
-			b.ResetControls()
+			b.Reset(BlockMIPS64FPF)
 			b.AddControl(cmp)
-			b.Aux = nil
 			return true
 		}
 		// match: (NE (XORconst [1] cmp:(SGT _ _)) yes no)
@@ -10087,10 +10041,8 @@ func rewriteBlockMIPS64(b *Block) bool {
 				break
 			}
 			_ = cmp.Args[1]
-			b.Kind = BlockMIPS64EQ
-			b.ResetControls()
+			b.Reset(BlockMIPS64EQ)
 			b.AddControl(cmp)
-			b.Aux = nil
 			return true
 		}
 		// match: (NE (XORconst [1] cmp:(SGTU _ _)) yes no)
@@ -10105,10 +10057,8 @@ func rewriteBlockMIPS64(b *Block) bool {
 				break
 			}
 			_ = cmp.Args[1]
-			b.Kind = BlockMIPS64EQ
-			b.ResetControls()
+			b.Reset(BlockMIPS64EQ)
 			b.AddControl(cmp)
-			b.Aux = nil
 			return true
 		}
 		// match: (NE (XORconst [1] cmp:(SGTconst _)) yes no)
@@ -10122,10 +10072,8 @@ func rewriteBlockMIPS64(b *Block) bool {
 			if cmp.Op != OpMIPS64SGTconst {
 				break
 			}
-			b.Kind = BlockMIPS64EQ
-			b.ResetControls()
+			b.Reset(BlockMIPS64EQ)
 			b.AddControl(cmp)
-			b.Aux = nil
 			return true
 		}
 		// match: (NE (XORconst [1] cmp:(SGTUconst _)) yes no)
@@ -10139,10 +10087,8 @@ func rewriteBlockMIPS64(b *Block) bool {
 			if cmp.Op != OpMIPS64SGTUconst {
 				break
 			}
-			b.Kind = BlockMIPS64EQ
-			b.ResetControls()
+			b.Reset(BlockMIPS64EQ)
 			b.AddControl(cmp)
-			b.Aux = nil
 			return true
 		}
 		// match: (NE (SGTUconst [1] x) yes no)
@@ -10153,10 +10099,8 @@ func rewriteBlockMIPS64(b *Block) bool {
 				break
 			}
 			x := v_0.Args[0]
-			b.Kind = BlockMIPS64EQ
-			b.ResetControls()
+			b.Reset(BlockMIPS64EQ)
 			b.AddControl(x)
-			b.Aux = nil
 			return true
 		}
 		// match: (NE (SGTU x (MOVVconst [0])) yes no)
@@ -10169,10 +10113,8 @@ func rewriteBlockMIPS64(b *Block) bool {
 			if v_0_1.Op != OpMIPS64MOVVconst || v_0_1.AuxInt != 0 {
 				break
 			}
-			b.Kind = BlockMIPS64NE
-			b.ResetControls()
+			b.Reset(BlockMIPS64NE)
 			b.AddControl(x)
-			b.Aux = nil
 			return true
 		}
 		// match: (NE (SGTconst [0] x) yes no)
@@ -10183,10 +10125,8 @@ func rewriteBlockMIPS64(b *Block) bool {
 				break
 			}
 			x := v_0.Args[0]
-			b.Kind = BlockMIPS64LTZ
-			b.ResetControls()
+			b.Reset(BlockMIPS64LTZ)
 			b.AddControl(x)
-			b.Aux = nil
 			return true
 		}
 		// match: (NE (SGT x (MOVVconst [0])) yes no)
@@ -10199,10 +10139,8 @@ func rewriteBlockMIPS64(b *Block) bool {
 			if v_0_1.Op != OpMIPS64MOVVconst || v_0_1.AuxInt != 0 {
 				break
 			}
-			b.Kind = BlockMIPS64GTZ
-			b.ResetControls()
+			b.Reset(BlockMIPS64GTZ)
 			b.AddControl(x)
-			b.Aux = nil
 			return true
 		}
 		// match: (NE (MOVVconst [0]) yes no)
@@ -10212,9 +10150,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 			if v_0.AuxInt != 0 {
 				break
 			}
-			b.Kind = BlockFirst
-			b.ResetControls()
-			b.Aux = nil
+			b.Reset(BlockFirst)
 			b.swapSuccessors()
 			return true
 		}
@@ -10227,9 +10163,7 @@ func rewriteBlockMIPS64(b *Block) bool {
 			if !(c != 0) {
 				break
 			}
-			b.Kind = BlockFirst
-			b.ResetControls()
-			b.Aux = nil
+			b.Reset(BlockFirst)
 			return true
 		}
 	}