runtime: drop haveexperiment, sys.GOEXPERIMENT

We have ways to statically access experiments now, so we don't need a
relatively clunky string-parsing dynamic way to do it.

Change-Id: I5d75480916eef4bde2c30d5fe30593180da77ff2
Reviewed-on: https://go-review.googlesource.com/c/go/+/307815
Trust: Austin Clements <austin@google.com>
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

diff --git a/src/cmd/internal/objabi/util.go b/src/cmd/internal/objabi/util.go
index ae03aac31ac4539311a32b09fc2300c729b0a603..ca3d3fc1a3269acffb177c879e9c5b210231d770 100644 (file)
--- a/src/cmd/internal/objabi/util.go
+++ b/src/cmd/internal/objabi/util.go
@@ -171,7 +171,6 @@ func init() {
        }
 
        // Set GOEXPERIMENT to the parsed and canonicalized set of experiments.
-       // This format must be parseable by runtime.haveexperiment.
        GOEXPERIMENT = expList()
 }
 

diff --git a/src/cmd/link/internal/ld/main.go b/src/cmd/link/internal/ld/main.go
index 78df50ee2d4a9d03c98d08465fc5c40ec0953b52..95c89f813be8f0fc7c0d6a56de19977065b152a9 100644 (file)
--- a/src/cmd/link/internal/ld/main.go
+++ b/src/cmd/link/internal/ld/main.go
@@ -118,8 +118,6 @@ func Main(arch *sys.Arch, theArch Arch) {
        addstrdata1(ctxt, "runtime.defaultGOROOT="+final)
        addstrdata1(ctxt, "cmd/internal/objabi.defaultGOROOT="+final)
 
-       addstrdata1(ctxt, "runtime/internal/sys.GOEXPERIMENT="+objabi.GOEXPERIMENT)
-
        // TODO(matloob): define these above and then check flag values here
        if ctxt.Arch.Family == sys.AMD64 && objabi.GOOS == "plan9" {
                flag.BoolVar(&flag8, "8", false, "use 64-bit addresses in symbol table")

diff --git a/src/runtime/heapdump.go b/src/runtime/heapdump.go
index e0913162a431484ed0da158a70de0f6bb9f872e2..934e55f49523061a8787551c0aff15d3e92a0ffa 100644 (file)
--- a/src/runtime/heapdump.go
+++ b/src/runtime/heapdump.go
@@ -532,7 +532,7 @@ func dumpparams() {
        dumpint(uint64(arenaStart))
        dumpint(uint64(arenaEnd))
        dumpstr(sys.GOARCH)
-       dumpstr(sys.GOEXPERIMENT)
+       dumpstr(buildVersion)
        dumpint(uint64(ncpu))
 }
 

diff --git a/src/runtime/internal/sys/arch.go b/src/runtime/internal/sys/arch.go
index f00c55913f824693526a144c06a718c957fd573b..3c99a2f7da0831048e2aa5ae24cb8914e5d83785 100644 (file)
--- a/src/runtime/internal/sys/arch.go
+++ b/src/runtime/internal/sys/arch.go
@@ -52,5 +52,3 @@ const MinFrameSize = _MinFrameSize
 // StackAlign is the required alignment of the SP register.
 // The stack must be at least word aligned, but some architectures require more.
 const StackAlign = _StackAlign
-
-var GOEXPERIMENT string // set by cmd/link

diff --git a/src/runtime/proc.go b/src/runtime/proc.go
index a256b6e04afa6ac49c9e21438c368fcdab659566..583ed73d848ce55affce4e3080031389b47cac7d 100644 (file)
--- a/src/runtime/proc.go
+++ b/src/runtime/proc.go
@@ -5,7 +5,6 @@
 package runtime
 
 import (
-       "internal/bytealg"
        "internal/cpu"
        "runtime/internal/atomic"
        "runtime/internal/sys"
@@ -6039,26 +6038,6 @@ func setMaxThreads(in int) (out int) {
        return
 }
 
-func haveexperiment(name string) bool {
-       // GOEXPERIMENT is a comma-separated list of enabled
-       // experiments. It's not the raw environment variable, but a
-       // pre-processed list from cmd/internal/objabi.
-       x := sys.GOEXPERIMENT
-       for x != "" {
-               xname := ""
-               i := bytealg.IndexByteString(x, ',')
-               if i < 0 {
-                       xname, x = x, ""
-               } else {
-                       xname, x = x[:i], x[i+1:]
-               }
-               if xname == name {
-                       return true
-               }
-       }
-       return false
-}
-
 //go:nosplit
 func procPin() int {
        _g_ := getg()