dashboard: remove noregabi builders

Regabi on AMD64 is now always enabled and cannot be disabled by
GOEXPERIMENT. It is not necessary to keep those builders.

Updates golang/go#40724.

Change-Id: I7c0d7782ad9e76a60c40675bec97dfe0a23833cf
Reviewed-on: https://go-review.googlesource.com/c/build/+/347390
Trust: Cherry Mui <cherryyz@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
diff --git a/dashboard/builders.go b/dashboard/builders.go
index 3969e20..0c4e56a 100644
--- a/dashboard/builders.go
+++ b/dashboard/builders.go
@@ -1729,59 +1729,6 @@
 		numTryTestHelpers: 4,
 	})
 	addBuilder(BuildConfig{
-		Name:     "linux-amd64-noregabi",
-		HostType: "host-linux-buster",
-		Notes:    "builder with GOEXPERIMENT=noregabi, see golang.org/issue/40724",
-		buildsRepo: func(repo, branch, goBranch string) bool {
-			return repo == "go" && branch == "master"
-		},
-		env: []string{
-			"GO_DISABLE_OUTBOUND_NETWORK=1",
-			"GOEXPERIMENT=noregabi",
-		},
-		GoDeps: []string{
-			"89b44b4e2bb2f88474d6b8476f5c28ea2aea9b28", // A master commit from 2020/12/20, just before a merge into dev.regabi, before the GOEXPERIMENT is used anywhere
-		},
-	})
-	addBuilder(BuildConfig{
-		Name:     "windows-amd64-noregabi",
-		HostType: "host-windows-amd64-2016",
-		Notes:    "builder with GOEXPERIMENT=noregabi, see golang.org/issue/40724",
-		buildsRepo: func(repo, branch, goBranch string) bool {
-			return repo == "go" && branch == "master"
-		},
-		env: []string{
-			"GO_DISABLE_OUTBOUND_NETWORK=1",
-			"GOEXPERIMENT=noregabi",
-			"GOARCH=amd64",
-			"GOHOSTARCH=amd64",
-			// cmd/go takes ~188 seconds on windows-amd64
-			// now, which is over the 180 second default
-			// dist test timeout. So, bump this builder
-			// up:
-			"GO_TEST_TIMEOUT_SCALE=2",
-		},
-		GoDeps: []string{
-			"89b44b4e2bb2f88474d6b8476f5c28ea2aea9b28", // A master commit from 2020/12/20, just before a merge into dev.regabi, before the GOEXPERIMENT is used anywhere
-		},
-	})
-	addBuilder(BuildConfig{
-		Name:           "darwin-amd64-noregabi",
-		HostType:       "host-darwin-10_15",
-		distTestAdjust: macTestPolicy,
-		Notes:          "builder with GOEXPERIMENT=noregabi, see golang.org/issue/40724",
-		buildsRepo: func(repo, branch, goBranch string) bool {
-			return repo == "go" && branch == "master"
-		},
-		env: []string{
-			"GO_DISABLE_OUTBOUND_NETWORK=1",
-			"GOEXPERIMENT=noregabi",
-		},
-		GoDeps: []string{
-			"89b44b4e2bb2f88474d6b8476f5c28ea2aea9b28", // A master commit from 2020/12/20, just before a merge into dev.regabi, before the GOEXPERIMENT is used anywhere
-		},
-	})
-	addBuilder(BuildConfig{
 		Name:                "linux-amd64-racecompile",
 		HostType:            "host-linux-bullseye",
 		tryBot:              nil, // TODO: add a func to conditionally run this trybot if compiler dirs are touched
diff --git a/dashboard/builders_test.go b/dashboard/builders_test.go
index 25eaa56..6851c05 100644
--- a/dashboard/builders_test.go
+++ b/dashboard/builders_test.go
@@ -611,9 +611,6 @@
 		{b("linux-amd64-unified@dev.typeparams", "go"), both},
 		{b("linux-amd64-unified@dev.typeparams", "tools"), both},
 		{b("linux-amd64-unified@dev.typeparams", "net"), none},
-
-		{b("linux-amd64-noregabi", "go"), onlyPost},
-		{b("linux-amd64-noregabi", "net"), none},
 	}
 	for _, tt := range tests {
 		t.Run(tt.br.testName, func(t *testing.T) {