runtime: remove fallback to pipe on platforms with pipe2

On Linux, the minimum required kernel version for Go 1.18 was be changed
to 2.6.32, see #45964. The pipe2 syscall was added in 2.6.27.

All other platforms already provide the pipe2 syscall in the minimum
supported version:
- DragonFly BSD added it in version 4.2, see
  https://www.dragonflybsd.org/release42/
- FreeBSD added it in version 10.0, see
  https://www.freebsd.org/cgi/man.cgi?pipe(2)#end
- NetBSD added it in version 6.0, see
  https://man.netbsd.org/pipe2.2#HISTORY
- OpenBSD added it in version 5.7, see
  https://man.openbsd.org/pipe.2#HISTORY
- Illumos supports it since 2013, see
  https://www.illumos.org/issues/3714
- Solaris supports it since 11.4

This also allows to remove setNonblock which was only used in the pipe
fallback path on these platforms.

Change-Id: I1f40d32fd3065d74e22af77b9ff2292b9cf66706
Reviewed-on: https://go-review.googlesource.com/c/go/+/389354
Trust: Tobias Klauser <tobias.klauser@gmail.com>
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

src/runtime/defs1_netbsd_386.go

@@ -7,7 +7,6 @@ const (
 	_EINTR  = 0x4
 	_EFAULT = 0xe
 	_EAGAIN = 0x23
-	_ENOSYS = 0x4e
 
 	_O_NONBLOCK = 0x4
 	_O_CLOEXEC  = 0x400000

src/runtime/defs1_netbsd_amd64.go

@@ -7,7 +7,6 @@ const (
 	_EINTR  = 0x4
 	_EFAULT = 0xe
 	_EAGAIN = 0x23
-	_ENOSYS = 0x4e
 
 	_O_NONBLOCK = 0x4
 	_O_CLOEXEC  = 0x400000

src/runtime/defs1_netbsd_arm.go

@@ -7,7 +7,6 @@ const (
 	_EINTR  = 0x4
 	_EFAULT = 0xe
 	_EAGAIN = 0x23
-	_ENOSYS = 0x4e
 
 	_O_NONBLOCK = 0x4
 	_O_CLOEXEC  = 0x400000

src/runtime/defs1_netbsd_arm64.go

@@ -7,7 +7,6 @@ const (
 	_EINTR  = 0x4
 	_EFAULT = 0xe
 	_EAGAIN = 0x23
-	_ENOSYS = 0x4e
 
 	_O_NONBLOCK = 0x4
 	_O_CLOEXEC  = 0x400000

src/runtime/defs1_solaris_amd64.go

@@ -13,7 +13,6 @@ const (
 	_ETIMEDOUT   = 0x91
 	_EWOULDBLOCK = 0xb
 	_EINPROGRESS = 0x96
-	_ENOSYS      = 0x59
 
 	_PROT_NONE  = 0x0
 	_PROT_READ  = 0x1

src/runtime/defs_dragonfly.go

@@ -31,7 +31,6 @@ const (
 	EFAULT = C.EFAULT
 	EBUSY  = C.EBUSY
 	EAGAIN = C.EAGAIN
-	ENOSYS = C.ENOSYS
 
 	O_NONBLOCK = C.O_NONBLOCK
 	O_CLOEXEC  = C.O_CLOEXEC

src/runtime/defs_dragonfly_amd64.go

@@ -10,7 +10,6 @@ const (
 	_EFAULT = 0xe
 	_EBUSY  = 0x10
 	_EAGAIN = 0x23
-	_ENOSYS = 0x4e
 
 	_O_NONBLOCK = 0x4
 	_O_CLOEXEC  = 0x20000

src/runtime/defs_freebsd.go

@@ -48,7 +48,6 @@ const (
 	EINTR  = C.EINTR
 	EFAULT = C.EFAULT
 	EAGAIN = C.EAGAIN
-	ENOSYS = C.ENOSYS
 
 	O_NONBLOCK = C.O_NONBLOCK
 	O_CLOEXEC  = C.O_CLOEXEC

src/runtime/defs_freebsd_386.go

@@ -16,7 +16,6 @@ const (
 	_EINTR     = 0x4
 	_EFAULT    = 0xe
 	_EAGAIN    = 0x23
-	_ENOSYS    = 0x4e
 	_ETIMEDOUT = 0x3c
 
 	_O_NONBLOCK = 0x4

src/runtime/defs_freebsd_amd64.go

@@ -16,7 +16,6 @@ const (
 	_EINTR     = 0x4
 	_EFAULT    = 0xe
 	_EAGAIN    = 0x23
-	_ENOSYS    = 0x4e
 	_ETIMEDOUT = 0x3c
 
 	_O_NONBLOCK = 0x4

src/runtime/defs_freebsd_arm.go

@@ -16,7 +16,6 @@ const (
 	_EINTR     = 0x4
 	_EFAULT    = 0xe
 	_EAGAIN    = 0x23
-	_ENOSYS    = 0x4e
 	_ETIMEDOUT = 0x3c
 
 	_O_NONBLOCK = 0x4

src/runtime/defs_freebsd_arm64.go

@@ -16,7 +16,6 @@ const (
 	_EINTR     = 0x4
 	_EFAULT    = 0xe
 	_EAGAIN    = 0x23
-	_ENOSYS    = 0x4e
 	_ETIMEDOUT = 0x3c
 
 	_O_NONBLOCK = 0x4

src/runtime/defs_linux.go

@@ -37,7 +37,6 @@ const (
 	EINTR  = C.EINTR
 	EAGAIN = C.EAGAIN
 	ENOMEM = C.ENOMEM
-	ENOSYS = C.ENOSYS
 
 	PROT_NONE  = C.PROT_NONE
 	PROT_READ  = C.PROT_READ
@@ -91,7 +90,7 @@ const (
 	SIGPWR    = C.SIGPWR
 	SIGSYS    = C.SIGSYS
 
-	SIGRTMIN  = C.SIGRTMIN
+	SIGRTMIN = C.SIGRTMIN
 
 	FPE_INTDIV = C.FPE_INTDIV
 	FPE_INTOVF = C.FPE_INTOVF

src/runtime/defs_linux_386.go

@@ -9,7 +9,6 @@ const (
 	_EINTR  = 0x4
 	_EAGAIN = 0xb
 	_ENOMEM = 0xc
-	_ENOSYS = 0x26
 
 	_PROT_NONE  = 0x0
 	_PROT_READ  = 0x1

src/runtime/defs_linux_amd64.go

@@ -9,7 +9,6 @@ const (
 	_EINTR  = 0x4
 	_EAGAIN = 0xb
 	_ENOMEM = 0xc
-	_ENOSYS = 0x26
 
 	_PROT_NONE  = 0x0
 	_PROT_READ  = 0x1

src/runtime/defs_linux_arm.go

@@ -11,7 +11,6 @@ const (
 	_EINTR  = 0x4
 	_ENOMEM = 0xc
 	_EAGAIN = 0xb
-	_ENOSYS = 0x26
 
 	_PROT_NONE  = 0
 	_PROT_READ  = 0x1

src/runtime/defs_linux_arm64.go

@@ -9,7 +9,6 @@ const (
 	_EINTR  = 0x4
 	_EAGAIN = 0xb
 	_ENOMEM = 0xc
-	_ENOSYS = 0x26
 
 	_PROT_NONE  = 0x0
 	_PROT_READ  = 0x1

src/runtime/defs_linux_mips64x.go

@@ -12,7 +12,6 @@ const (
 	_EINTR  = 0x4
 	_EAGAIN = 0xb
 	_ENOMEM = 0xc
-	_ENOSYS = 0x59
 
 	_PROT_NONE  = 0x0
 	_PROT_READ  = 0x1

src/runtime/defs_linux_mipsx.go

@@ -12,7 +12,6 @@ const (
 	_EINTR  = 0x4
 	_EAGAIN = 0xb
 	_ENOMEM = 0xc
-	_ENOSYS = 0x59
 
 	_PROT_NONE  = 0x0
 	_PROT_READ  = 0x1

src/runtime/defs_linux_ppc64.go

@@ -9,7 +9,6 @@ const (
 	_EINTR  = 0x4
 	_EAGAIN = 0xb
 	_ENOMEM = 0xc
-	_ENOSYS = 0x26
 
 	_PROT_NONE  = 0x0
 	_PROT_READ  = 0x1

src/runtime/defs_linux_ppc64le.go

@@ -9,7 +9,6 @@ const (
 	_EINTR  = 0x4
 	_EAGAIN = 0xb
 	_ENOMEM = 0xc
-	_ENOSYS = 0x26
 
 	_PROT_NONE  = 0x0
 	_PROT_READ  = 0x1

src/runtime/defs_linux_riscv64.go

@@ -10,7 +10,6 @@ const (
 	_EINTR  = 0x4
 	_EAGAIN = 0xb
 	_ENOMEM = 0xc
-	_ENOSYS = 0x26
 
 	_PROT_NONE  = 0x0
 	_PROT_READ  = 0x1

src/runtime/defs_linux_s390x.go

@@ -10,7 +10,6 @@ const (
 	_EINTR  = 0x4
 	_EAGAIN = 0xb
 	_ENOMEM = 0xc
-	_ENOSYS = 0x26
 
 	_PROT_NONE  = 0x0
 	_PROT_READ  = 0x1

src/runtime/defs_netbsd.go

@@ -33,7 +33,6 @@ const (
 	EINTR  = C.EINTR
 	EFAULT = C.EFAULT
 	EAGAIN = C.EAGAIN
-	ENOSYS = C.ENOSYS
 
 	O_NONBLOCK = C.O_NONBLOCK
 	O_CLOEXEC  = C.O_CLOEXEC

src/runtime/defs_openbsd.go

@@ -34,7 +34,6 @@ const (
 	EINTR  = C.EINTR
 	EFAULT = C.EFAULT
 	EAGAIN = C.EAGAIN
-	ENOSYS = C.ENOSYS
 
 	O_NONBLOCK = C.O_NONBLOCK
 	O_CLOEXEC  = C.O_CLOEXEC

src/runtime/defs_openbsd_386.go

@@ -9,7 +9,6 @@ const (
 	_EINTR  = 0x4
 	_EFAULT = 0xe
 	_EAGAIN = 0x23
-	_ENOSYS = 0x4e
 
 	_O_NONBLOCK = 0x4
 	_O_CLOEXEC  = 0x10000

src/runtime/defs_openbsd_amd64.go

@@ -9,7 +9,6 @@ const (
 	_EINTR  = 0x4
 	_EFAULT = 0xe
 	_EAGAIN = 0x23
-	_ENOSYS = 0x4e
 
 	_O_NONBLOCK = 0x4
 	_O_CLOEXEC  = 0x10000

src/runtime/defs_openbsd_arm.go

@@ -9,7 +9,6 @@ const (
 	_EINTR  = 0x4
 	_EFAULT = 0xe
 	_EAGAIN = 0x23
-	_ENOSYS = 0x4e
 
 	_O_NONBLOCK = 0x4
 	_O_CLOEXEC  = 0x10000

src/runtime/defs_openbsd_arm64.go

@@ -10,7 +10,6 @@ const (
 	_EINTR  = 0x4
 	_EFAULT = 0xe
 	_EAGAIN = 0x23
-	_ENOSYS = 0x4e
 
 	_O_NONBLOCK = 0x4
 	_O_CLOEXEC  = 0x10000

src/runtime/defs_openbsd_mips64.go

@@ -16,7 +16,6 @@ const (
 	_EINTR  = 0x4
 	_EFAULT = 0xe
 	_EAGAIN = 0x23
-	_ENOSYS = 0x4e
 
 	_O_NONBLOCK = 0x4
 	_O_CLOEXEC  = 0x10000

src/runtime/defs_solaris.go

@@ -43,7 +43,6 @@ const (
 	ETIMEDOUT   = C.ETIMEDOUT
 	EWOULDBLOCK = C.EWOULDBLOCK
 	EINPROGRESS = C.EINPROGRESS
-	ENOSYS      = C.ENOSYS
 
 	PROT_NONE  = C.PROT_NONE
 	PROT_READ  = C.PROT_READ

src/runtime/export_aix_test.go

@@ -5,3 +5,4 @@
 package runtime
 
 var Fcntl = syscall_fcntl1
+var SetNonblock = setNonblock

src/runtime/export_darwin_test.go

@@ -11,3 +11,5 @@ func Fcntl(fd, cmd, arg uintptr) (uintptr, uintptr) {
 	}
 	return uintptr(r), 0
 }
+
+var SetNonblock = setNonblock

src/runtime/export_pipe2_test.go

@@ -7,9 +7,5 @@
 package runtime
 
 func Pipe() (r, w int32, errno int32) {
-	r, w, errno = pipe2(0)
-	if errno == _ENOSYS {
-		return pipe()
-	}
-	return r, w, errno
+	return pipe2(0)
 }

src/runtime/export_unix_test.go

@@ -9,7 +9,6 @@ package runtime
 import "unsafe"
 
 var NonblockingPipe = nonblockingPipe
-var SetNonblock = setNonblock
 var Closeonexec = closeonexec
 
 func sigismember(mask *sigset, i int) bool {

src/runtime/nbpipe_pipe2.go

@@ -7,16 +7,5 @@
 package runtime
 
 func nonblockingPipe() (r, w int32, errno int32) {
-	r, w, errno = pipe2(_O_NONBLOCK | _O_CLOEXEC)
-	if errno == -_ENOSYS {
-		r, w, errno = pipe()
-		if errno != 0 {
-			return -1, -1, errno
-		}
-		closeonexec(r)
-		setNonblock(r)
-		closeonexec(w)
-		setNonblock(w)
-	}
-	return r, w, errno
+	return pipe2(_O_NONBLOCK | _O_CLOEXEC)
 }

src/runtime/nbpipe_pipe_test.go

@@ -0,0 +1,38 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build aix || darwin
+
+package runtime_test
+
+import (
+	"runtime"
+	"syscall"
+	"testing"
+)
+
+func TestSetNonblock(t *testing.T) {
+	t.Parallel()
+
+	r, w, errno := runtime.Pipe()
+	if errno != 0 {
+		t.Fatal(syscall.Errno(errno))
+	}
+	defer func() {
+		runtime.Close(r)
+		runtime.Close(w)
+	}()
+
+	checkIsPipe(t, r, w)
+
+	runtime.SetNonblock(r)
+	runtime.SetNonblock(w)
+	checkNonblocking(t, r, "reader")
+	checkNonblocking(t, w, "writer")
+
+	runtime.Closeonexec(r)
+	runtime.Closeonexec(w)
+	checkCloseonexec(t, r, "reader")
+	checkCloseonexec(t, w, "writer")
+}

src/runtime/nbpipe_test.go

@@ -66,28 +66,3 @@ func checkCloseonexec(t *testing.T, fd int32, name string) {
 		t.Errorf("FD_CLOEXEC not set in %s flags %#x", name, flags)
 	}
 }
-
-func TestSetNonblock(t *testing.T) {
-	t.Parallel()
-
-	r, w, errno := runtime.Pipe()
-	if errno != 0 {
-		t.Fatal(syscall.Errno(errno))
-	}
-	defer func() {
-		runtime.Close(r)
-		runtime.Close(w)
-	}()
-
-	checkIsPipe(t, r, w)
-
-	runtime.SetNonblock(r)
-	runtime.SetNonblock(w)
-	checkNonblocking(t, r, "reader")
-	checkNonblocking(t, w, "writer")
-
-	runtime.Closeonexec(r)
-	runtime.Closeonexec(w)
-	checkCloseonexec(t, r, "reader")
-	checkCloseonexec(t, w, "writer")
-}

src/runtime/os3_solaris.go

@@ -561,13 +561,6 @@ func write1(fd uintptr, buf unsafe.Pointer, nbyte int32) int32 {
 	return -int32(err)
 }
 
-//go:nosplit
-func pipe() (r, w int32, errno int32) {
-	var p [2]int32
-	_, e := sysvicall1Err(&libc_pipe, uintptr(noescape(unsafe.Pointer(&p))))
-	return p[0], p[1], int32(e)
-}
-
 //go:nosplit
 func pipe2(flags int32) (r, w int32, errno int32) {
 	var p [2]int32
@@ -580,12 +573,6 @@ func closeonexec(fd int32) {
 	fcntl(fd, _F_SETFD, _FD_CLOEXEC)
 }
 
-//go:nosplit
-func setNonblock(fd int32) {
-	flags := fcntl(fd, _F_GETFL, 0)
-	fcntl(fd, _F_SETFL, flags|_O_NONBLOCK)
-}
-
 func osyield1()
 
 //go:nosplit

src/runtime/os_dragonfly.go

@@ -62,10 +62,8 @@ func kqueue() int32
 //go:noescape
 func kevent(kq int32, ch *keventt, nch int32, ev *keventt, nev int32, ts *timespec) int32
 
-func pipe() (r, w int32, errno int32)
 func pipe2(flags int32) (r, w int32, errno int32)
 func closeonexec(fd int32)
-func setNonblock(fd int32)
 
 // From DragonFly's <sys/sysctl.h>
 const (

src/runtime/os_freebsd.go

@@ -47,10 +47,8 @@ func kqueue() int32
 //go:noescape
 func kevent(kq int32, ch *keventt, nch int32, ev *keventt, nev int32, ts *timespec) int32
 
-func pipe() (r, w int32, errno int32)
 func pipe2(flags int32) (r, w int32, errno int32)
 func closeonexec(fd int32)
-func setNonblock(fd int32)
 
 // From FreeBSD's <sys/sysctl.h>
 const (

src/runtime/os_linux.go

@@ -446,9 +446,7 @@ func osyield_no_g() {
 	osyield()
 }
 
-func pipe() (r, w int32, errno int32)
 func pipe2(flags int32) (r, w int32, errno int32)
-func setNonblock(fd int32)
 
 const (
 	_si_max_size    = 128

src/runtime/os_netbsd.go

@@ -78,10 +78,8 @@ func kqueue() int32
 //go:noescape
 func kevent(kq int32, ch *keventt, nch int32, ev *keventt, nev int32, ts *timespec) int32
 
-func pipe() (r, w int32, errno int32)
 func pipe2(flags int32) (r, w int32, errno int32)
 func closeonexec(fd int32)
-func setNonblock(fd int32)
 
 const (
 	_ESRCH     = 3

src/runtime/os_openbsd_syscall2.go

@@ -70,7 +70,6 @@ func sigprocmask(how int32, new, old *sigset) {
 	}
 }
 
-func pipe() (r, w int32, errno int32)
 func pipe2(flags int32) (r, w int32, errno int32)
 
 //go:noescape
@@ -95,6 +94,5 @@ func nanotime1() int64
 func sigaltstack(new, old *stackt)
 
 func closeonexec(fd int32)
-func setNonblock(fd int32)
 
 func walltime() (sec int64, nsec int32)

src/runtime/sys_dragonfly_amd64.s

@@ -109,21 +109,6 @@ TEXT runtime·read(SB),NOSPLIT,$-8
 	MOVL	AX, ret+24(FP)
 	RET
 
-// func pipe() (r, w int32, errno int32)
-TEXT runtime·pipe(SB),NOSPLIT,$0-12
-	MOVL	$42, AX
-	SYSCALL
-	JCC	pipeok
-	MOVL	$-1,r+0(FP)
-	MOVL	$-1,w+4(FP)
-	MOVL	AX, errno+8(FP)
-	RET
-pipeok:
-	MOVL	AX, r+0(FP)
-	MOVL	DX, w+4(FP)
-	MOVL	$0, errno+8(FP)
-	RET
-
 // func pipe2(flags int32) (r, w int32, errno int32)
 TEXT runtime·pipe2(SB),NOSPLIT,$0-20
 	MOVL	$0, DI
@@ -402,18 +387,3 @@ TEXT runtime·closeonexec(SB),NOSPLIT,$0
 	MOVL	$92, AX		// fcntl
 	SYSCALL
 	RET
-
-// func runtime·setNonblock(int32 fd)
-TEXT runtime·setNonblock(SB),NOSPLIT,$0-4
-	MOVL    fd+0(FP), DI  // fd
-	MOVQ    $3, SI  // F_GETFL
-	MOVQ    $0, DX
-	MOVL	$92, AX // fcntl
-	SYSCALL
-	MOVL	fd+0(FP), DI // fd
-	MOVQ	$4, SI // F_SETFL
-	MOVQ	$4, DX // O_NONBLOCK
-	ORL	AX, DX
-	MOVL	$92, AX // fcntl
-	SYSCALL
-	RET

src/runtime/sys_freebsd_386.s

@@ -101,21 +101,6 @@ TEXT runtime·read(SB),NOSPLIT,$-4
 	MOVL	AX, ret+12(FP)
 	RET
 
-// func pipe() (r, w int32, errno int32)
-TEXT runtime·pipe(SB),NOSPLIT,$8-12
-	MOVL	$42, AX
-	INT	$0x80
-	JAE	ok
-	MOVL	$0, r+0(FP)
-	MOVL	$0, w+4(FP)
-	MOVL	AX, errno+8(FP)
-	RET
-ok:
-	MOVL	AX, r+0(FP)
-	MOVL	DX, w+4(FP)
-	MOVL	$0, errno+8(FP)
-	RET
-
 // func pipe2(flags int32) (r, w int32, errno int32)
 TEXT runtime·pipe2(SB),NOSPLIT,$12-16
 	MOVL	$542, AX
@@ -443,23 +428,6 @@ TEXT runtime·closeonexec(SB),NOSPLIT,$32
 	NEGL	AX
 	RET
 
-// func runtime·setNonblock(fd int32)
-TEXT runtime·setNonblock(SB),NOSPLIT,$16-4
-	MOVL	$92, AX // fcntl
-	MOVL	fd+0(FP), BX // fd
-	MOVL	BX, 4(SP)
-	MOVL	$3, 8(SP) // F_GETFL
-	MOVL	$0, 12(SP)
-	INT	$0x80
-	MOVL	fd+0(FP), BX // fd
-	MOVL	BX, 4(SP)
-	MOVL	$4, 8(SP) // F_SETFL
-	ORL	$4, AX // O_NONBLOCK
-	MOVL	AX, 12(SP)
-	MOVL	$92, AX // fcntl
-	INT	$0x80
-	RET
-
 // func cpuset_getaffinity(level int, which int, id int64, size int, mask *byte) int32
 TEXT runtime·cpuset_getaffinity(SB), NOSPLIT, $0-28
 	MOVL	$487, AX

src/runtime/sys_freebsd_amd64.s

@@ -102,21 +102,6 @@ TEXT runtime·read(SB),NOSPLIT,$-8
 	MOVL	AX, ret+24(FP)
 	RET
 
-// func pipe() (r, w int32, errno int32)
-TEXT runtime·pipe(SB),NOSPLIT,$0-12
-	MOVL	$42, AX
-	SYSCALL
-	JCC	ok
-	MOVL	$0, r+0(FP)
-	MOVL	$0, w+4(FP)
-	MOVL	AX, errno+8(FP)
-	RET
-ok:
-	MOVL	AX, r+0(FP)
-	MOVL	DX, w+4(FP)
-	MOVL	$0, errno+8(FP)
-	RET
-
 // func pipe2(flags int32) (r, w int32, errno int32)
 TEXT runtime·pipe2(SB),NOSPLIT,$0-20
 	LEAQ	r+8(FP), DI
@@ -491,21 +476,6 @@ TEXT runtime·closeonexec(SB),NOSPLIT,$0
 	SYSCALL
 	RET
 
-// func runtime·setNonblock(int32 fd)
-TEXT runtime·setNonblock(SB),NOSPLIT,$0-4
-	MOVL    fd+0(FP), DI  // fd
-	MOVQ    $3, SI  // F_GETFL
-	MOVQ    $0, DX
-	MOVL	$92, AX // fcntl
-	SYSCALL
-	MOVL	fd+0(FP), DI // fd
-	MOVQ	$4, SI // F_SETFL
-	MOVQ	$4, DX // O_NONBLOCK
-	ORL	AX, DX
-	MOVL	$92, AX // fcntl
-	SYSCALL
-	RET
-
 // func cpuset_getaffinity(level int, which int, id int64, size int, mask *byte) int32
 TEXT runtime·cpuset_getaffinity(SB), NOSPLIT, $0-44
 	MOVQ	level+0(FP), DI

src/runtime/sys_freebsd_arm.s

@@ -20,7 +20,6 @@
 #define SYS_close (SYS_BASE + 6)
 #define SYS_getpid (SYS_BASE + 20)
 #define SYS_kill (SYS_BASE + 37)
-#define SYS_pipe (SYS_BASE + 42)
 #define SYS_sigaltstack (SYS_BASE + 53)
 #define SYS_munmap (SYS_BASE + 73)
 #define SYS_madvise (SYS_BASE + 75)
@@ -123,23 +122,6 @@ TEXT runtime·read(SB),NOSPLIT|NOFRAME,$0
 	MOVW	R0, ret+12(FP)
 	RET
 
-// func pipe() (r, w int32, errno int32)
-TEXT runtime·pipe(SB),NOSPLIT,$0-12
-	MOVW	$SYS_pipe, R7
-	SWI	$0
-	BCC	ok
-	MOVW	$0, R1
-	MOVW	R1, r+0(FP)
-	MOVW	R1, w+4(FP)
-	MOVW	R0, errno+8(FP)
-	RET
-ok:
-	MOVW	R0, r+0(FP)
-	MOVW	R1, w+4(FP)
-	MOVW	$0, R1
-	MOVW	R1, errno+8(FP)
-	RET
-
 // func pipe2(flags int32) (r, w int32, errno int32)
 TEXT runtime·pipe2(SB),NOSPLIT,$0-16
 	MOVW	$r+4(FP), R0
@@ -414,20 +396,6 @@ TEXT runtime·closeonexec(SB),NOSPLIT,$0
 	SWI $0
 	RET
 
-// func runtime·setNonblock(fd int32)
-TEXT runtime·setNonblock(SB),NOSPLIT,$0-4
-	MOVW	fd+0(FP), R0	// fd
-	MOVW	$3, R1	// F_GETFL
-	MOVW	$0, R2
-	MOVW	$SYS_fcntl, R7
-	SWI	$0
-	ORR	$0x4, R0, R2	// O_NONBLOCK
-	MOVW	fd+0(FP), R0	// fd
-	MOVW	$4, R1	// F_SETFL
-	MOVW	$SYS_fcntl, R7
-	SWI	$0
-	RET
-
 // TODO: this is only valid for ARMv7+
 TEXT ·publicationBarrier(SB),NOSPLIT|NOFRAME,$0-0
 	B	runtime·armPublicationBarrier(SB)

src/runtime/sys_freebsd_arm64.s

@@ -133,18 +133,6 @@ ok:
 	MOVW	R0, ret+8(FP)
 	RET
 
-// func pipe() (r, w int32, errno int32)
-TEXT runtime·pipe(SB),NOSPLIT|NOFRAME,$0-12
-	MOVD	$r+0(FP), R0
-	MOVW	$0, R1
-	MOVD	$SYS_pipe2, R8
-	SVC
-	BCC	ok
-	NEG	R0, R0
-ok:
-	MOVW	R0, errno+8(FP)
-	RET
-
 // func pipe2(flags int32) (r, w int32, errno int32)
 TEXT runtime·pipe2(SB),NOSPLIT|NOFRAME,$0-20
 	MOVD	$r+8(FP), R0
@@ -492,20 +480,6 @@ TEXT runtime·closeonexec(SB),NOSPLIT|NOFRAME,$0
 	SVC
 	RET
 
-// func runtime·setNonblock(fd int32)
-TEXT runtime·setNonblock(SB),NOSPLIT,$0-4
-	MOVW	fd+0(FP), R0
-	MOVD	$F_GETFL, R1
-	MOVD	$0, R2
-	MOVD	$SYS_fcntl, R8
-	SVC
-	ORR	$O_NONBLOCK, R0, R2
-	MOVW	fd+0(FP), R0
-	MOVW	$F_SETFL, R1
-	MOVW	$SYS_fcntl, R7
-	SVC
-	RET
-
 // func getCntxct(physical bool) uint32
 TEXT runtime·getCntxct(SB),NOSPLIT,$0
 	MOVB	physical+0(FP), R0

src/runtime/sys_linux_386.s

@@ -32,7 +32,6 @@
 #define SYS_getpid		20
 #define SYS_access		33
 #define SYS_kill		37
-#define SYS_pipe		42
 #define SYS_brk 		45
 #define SYS_fcntl		55
 #define SYS_munmap		91
@@ -130,14 +129,6 @@ TEXT runtime·read(SB),NOSPLIT,$0
 	MOVL	AX, ret+12(FP)
 	RET
 
-// func pipe() (r, w int32, errno int32)
-TEXT runtime·pipe(SB),NOSPLIT,$0-12
-	MOVL	$SYS_pipe, AX
-	LEAL	r+0(FP), BX
-	INVOKE_SYSCALL
-	MOVL	AX, errno+8(FP)
-	RET
-
 // func pipe2(flags int32) (r, w int32, errno int32)
 TEXT runtime·pipe2(SB),NOSPLIT,$0-16
 	MOVL	$SYS_pipe2, AX
@@ -782,21 +773,6 @@ TEXT runtime·closeonexec(SB),NOSPLIT,$0
 	INVOKE_SYSCALL
 	RET
 
-// func runtime·setNonblock(fd int32)
-TEXT runtime·setNonblock(SB),NOSPLIT,$0-4
-	MOVL	$SYS_fcntl, AX
-	MOVL	fd+0(FP), BX // fd
-	MOVL	$3, CX // F_GETFL
-	MOVL	$0, DX
-	INVOKE_SYSCALL
-	MOVL	fd+0(FP), BX // fd
-	MOVL	$4, CX // F_SETFL
-	MOVL	$0x800, DX // O_NONBLOCK
-	ORL	AX, DX
-	MOVL	$SYS_fcntl, AX
-	INVOKE_SYSCALL
-	RET
-
 // int access(const char *name, int mode)
 TEXT runtime·access(SB),NOSPLIT,$0
 	MOVL	$SYS_access, AX

src/runtime/sys_linux_amd64.s

@@ -22,7 +22,6 @@
 #define SYS_rt_sigaction	13
 #define SYS_rt_sigprocmask	14
 #define SYS_rt_sigreturn	15
-#define SYS_pipe		22
 #define SYS_sched_yield 	24
 #define SYS_mincore		27
 #define SYS_madvise		28
@@ -114,14 +113,6 @@ TEXT runtime·read(SB),NOSPLIT,$0-28
 	MOVL	AX, ret+24(FP)
 	RET
 
-// func pipe() (r, w int32, errno int32)
-TEXT runtime·pipe(SB),NOSPLIT,$0-12
-	LEAQ	r+0(FP), DI
-	MOVL	$SYS_pipe, AX
-	SYSCALL
-	MOVL	AX, errno+8(FP)
-	RET
-
 // func pipe2(flags int32) (r, w int32, errno int32)
 TEXT runtime·pipe2(SB),NOSPLIT,$0-20
 	LEAQ	r+8(FP), DI
@@ -708,21 +699,6 @@ TEXT runtime·closeonexec(SB),NOSPLIT,$0
 	SYSCALL
 	RET
 
-// func runtime·setNonblock(int32 fd)
-TEXT runtime·setNonblock(SB),NOSPLIT,$0-4
-	MOVL    fd+0(FP), DI  // fd
-	MOVQ    $3, SI  // F_GETFL
-	MOVQ    $0, DX
-	MOVL	$SYS_fcntl, AX
-	SYSCALL
-	MOVL	fd+0(FP), DI // fd
-	MOVQ	$4, SI // F_SETFL
-	MOVQ	$0x800, DX // O_NONBLOCK
-	ORL	AX, DX
-	MOVL	$SYS_fcntl, AX
-	SYSCALL
-	RET
-
 // int access(const char *name, int mode)
 TEXT runtime·access(SB),NOSPLIT,$0
 	// This uses faccessat instead of access, because Android O blocks access.

src/runtime/sys_linux_arm.s

@@ -23,7 +23,6 @@
 #define SYS_close (SYS_BASE + 6)
 #define SYS_getpid (SYS_BASE + 20)
 #define SYS_kill (SYS_BASE + 37)
-#define SYS_pipe (SYS_BASE + 42)
 #define SYS_clone (SYS_BASE + 120)
 #define SYS_rt_sigreturn (SYS_BASE + 173)
 #define SYS_rt_sigaction (SYS_BASE + 174)
@@ -98,14 +97,6 @@ TEXT runtime·read(SB),NOSPLIT,$0
 	MOVW	R0, ret+12(FP)
 	RET
 
-// func pipe() (r, w int32, errno int32)
-TEXT runtime·pipe(SB),NOSPLIT,$0-12
-	MOVW	$r+0(FP), R0
-	MOVW	$SYS_pipe, R7
-	SWI	$0
-	MOVW	R0, errno+8(FP)
-	RET
-
 // func pipe2(flags int32) (r, w int32, errno int32)
 TEXT runtime·pipe2(SB),NOSPLIT,$0-16
 	MOVW	$r+4(FP), R0
@@ -717,20 +708,6 @@ TEXT runtime·closeonexec(SB),NOSPLIT,$0
 	SWI	$0
 	RET
 
-// func runtime·setNonblock(fd int32)
-TEXT runtime·setNonblock(SB),NOSPLIT,$0-4
-	MOVW	fd+0(FP), R0	// fd
-	MOVW	$3, R1	// F_GETFL
-	MOVW	$0, R2
-	MOVW	$SYS_fcntl, R7
-	SWI	$0
-	ORR	$0x800, R0, R2	// O_NONBLOCK
-	MOVW	fd+0(FP), R0	// fd
-	MOVW	$4, R1	// F_SETFL
-	MOVW	$SYS_fcntl, R7
-	SWI	$0
-	RET
-
 // b __kuser_get_tls @ 0xffff0fe0
 TEXT runtime·read_tls_fallback(SB),NOSPLIT|NOFRAME,$0
 	MOVW	$0xffff0fe0, R0

src/runtime/sys_linux_arm64.s

@@ -113,15 +113,6 @@ TEXT runtime·read(SB),NOSPLIT|NOFRAME,$0-28
 	MOVW	R0, ret+24(FP)
 	RET
 
-// func pipe() (r, w int32, errno int32)
-TEXT runtime·pipe(SB),NOSPLIT|NOFRAME,$0-12
-	MOVD	$r+0(FP), R0
-	MOVW	$0, R1
-	MOVW	$SYS_pipe2, R8
-	SVC
-	MOVW	R0, errno+8(FP)
-	RET
-
 // func pipe2(flags int32) (r, w int32, errno int32)
 TEXT runtime·pipe2(SB),NOSPLIT|NOFRAME,$0-20
 	MOVD	$r+8(FP), R0
@@ -740,21 +731,6 @@ TEXT runtime·closeonexec(SB),NOSPLIT|NOFRAME,$0
 	SVC
 	RET
 
-// func runtime·setNonblock(int32 fd)
-TEXT runtime·setNonblock(SB),NOSPLIT|NOFRAME,$0-4
-	MOVW	fd+0(FP), R0 // fd
-	MOVD	$3, R1	// F_GETFL
-	MOVD	$0, R2
-	MOVD	$SYS_fcntl, R8
-	SVC
-	MOVD	$0x800, R2 // O_NONBLOCK
-	ORR	R0, R2
-	MOVW	fd+0(FP), R0 // fd
-	MOVD	$4, R1	// F_SETFL
-	MOVD	$SYS_fcntl, R8
-	SVC
-	RET
-
 // int access(const char *name, int mode)
 TEXT runtime·access(SB),NOSPLIT,$0-20
 	MOVD	$AT_FDCWD, R0

src/runtime/sys_linux_mips64x.s

@@ -113,17 +113,6 @@ TEXT runtime·read(SB),NOSPLIT|NOFRAME,$0-28
 	MOVW	R2, ret+24(FP)
 	RET
 
-// func pipe() (r, w int32, errno int32)
-TEXT runtime·pipe(SB),NOSPLIT|NOFRAME,$0-12
-	MOVV	$r+0(FP), R4
-	MOVV	R0, R5
-	MOVV	$SYS_pipe2, R2
-	SYSCALL
-	BEQ	R7, 2(PC)
-	SUBVU	R2, R0, R2	// caller expects negative errno
-	MOVW	R2, errno+8(FP)
-	RET
-
 // func pipe2(flags int32) (r, w int32, errno int32)
 TEXT runtime·pipe2(SB),NOSPLIT|NOFRAME,$0-20
 	MOVV	$r+8(FP), R4
@@ -635,21 +624,6 @@ TEXT runtime·closeonexec(SB),NOSPLIT|NOFRAME,$0
 	SYSCALL
 	RET
 
-// func runtime·setNonblock(int32 fd)
-TEXT runtime·setNonblock(SB),NOSPLIT|NOFRAME,$0-4
-	MOVW	fd+0(FP), R4 // fd
-	MOVV	$3, R5	// F_GETFL
-	MOVV	$0, R6
-	MOVV	$SYS_fcntl, R2
-	SYSCALL
-	MOVW	$0x80, R6 // O_NONBLOCK
-	OR	R2, R6
-	MOVW	fd+0(FP), R4 // fd
-	MOVV	$4, R5	// F_SETFL
-	MOVV	$SYS_fcntl, R2
-	SYSCALL
-	RET
-
 // func sbrk0() uintptr
 TEXT runtime·sbrk0(SB),NOSPLIT|NOFRAME,$0-8
 	// Implemented as brk(NULL).

src/runtime/sys_linux_mipsx.s

@@ -19,7 +19,6 @@
 #define SYS_close		4006
 #define SYS_getpid		4020
 #define SYS_kill		4037
-#define SYS_pipe		4042
 #define SYS_brk			4045
 #define SYS_fcntl		4055
 #define SYS_mmap		4090
@@ -112,23 +111,6 @@ TEXT runtime·read(SB),NOSPLIT,$0-16
 	MOVW	R2, ret+12(FP)
 	RET
 
-// func pipe() (r, w int32, errno int32)
-TEXT runtime·pipe(SB),NOSPLIT,$0-12
-	MOVW	$SYS_pipe, R2
-	SYSCALL
-	BEQ	R7, pipeok
-	MOVW	$-1, R1
-	MOVW	R1, r+0(FP)
-	MOVW	R1, w+4(FP)
-	SUBU	R2, R0, R2	// caller expects negative errno
-	MOVW	R2, errno+8(FP)
-	RET
-pipeok:
-	MOVW	R2, r+0(FP)
-	MOVW	R3, w+4(FP)
-	MOVW	R0, errno+8(FP)
-	RET
-
 // func pipe2(flags int32) (r, w int32, errno int32)
 TEXT runtime·pipe2(SB),NOSPLIT,$0-16
 	MOVW	$r+4(FP), R4
@@ -559,21 +541,6 @@ TEXT runtime·closeonexec(SB),NOSPLIT,$0-4
 	SYSCALL
 	RET
 
-// func runtime·setNonblock(int32 fd)
-TEXT runtime·setNonblock(SB),NOSPLIT,$0-4
-	MOVW	fd+0(FP), R4 // fd
-	MOVW	$3, R5	// F_GETFL
-	MOVW	$0, R6
-	MOVW	$SYS_fcntl, R2
-	SYSCALL
-	MOVW	$0x80, R6 // O_NONBLOCK
-	OR	R2, R6
-	MOVW	fd+0(FP), R4 // fd
-	MOVW	$4, R5	// F_SETFL
-	MOVW	$SYS_fcntl, R2
-	SYSCALL
-	RET
-
 // func sbrk0() uintptr
 TEXT runtime·sbrk0(SB),NOSPLIT,$0-4
 	// Implemented as brk(NULL).

src/runtime/sys_linux_ppc64x.s

@@ -20,7 +20,6 @@
 #define SYS_close		  6
 #define SYS_getpid		 20
 #define SYS_kill		 37
-#define SYS_pipe		 42
 #define SYS_brk			 45
 #define SYS_fcntl		 55
 #define SYS_mmap		 90
@@ -104,13 +103,6 @@ TEXT runtime·read(SB),NOSPLIT|NOFRAME,$0-28
 	MOVW	R3, ret+24(FP)
 	RET
 
-// func pipe() (r, w int32, errno int32)
-TEXT runtime·pipe(SB),NOSPLIT|NOFRAME,$0-12
-	ADD	$FIXED_FRAME, R1, R3
-	SYSCALL	$SYS_pipe
-	MOVW	R3, errno+8(FP)
-	RET
-
 // func pipe2(flags int32) (r, w int32, errno int32)
 TEXT runtime·pipe2(SB),NOSPLIT|NOFRAME,$0-20
 	ADD	$FIXED_FRAME+8, R1, R3
@@ -933,18 +925,6 @@ TEXT runtime·closeonexec(SB),NOSPLIT|NOFRAME,$0
 	SYSCALL	$SYS_fcntl
 	RET
 
-// func runtime·setNonblock(int32 fd)
-TEXT runtime·setNonblock(SB),NOSPLIT|NOFRAME,$0-4
-	MOVW	fd+0(FP), R3 // fd
-	MOVD	$3, R4	// F_GETFL
-	MOVD	$0, R5
-	SYSCALL	$SYS_fcntl
-	OR	$0x800, R3, R5 // O_NONBLOCK
-	MOVW	fd+0(FP), R3 // fd
-	MOVD	$4, R4	// F_SETFL
-	SYSCALL	$SYS_fcntl
-	RET
-
 // func sbrk0() uintptr
 TEXT runtime·sbrk0(SB),NOSPLIT|NOFRAME,$0
 	// Implemented as brk(NULL).

src/runtime/sys_linux_riscv64.s

@@ -118,15 +118,6 @@ TEXT runtime·read(SB),NOSPLIT|NOFRAME,$0-28
 	MOVW	A0, ret+24(FP)
 	RET
 
-// func pipe() (r, w int32, errno int32)
-TEXT runtime·pipe(SB),NOSPLIT|NOFRAME,$0-12
-	MOV	$r+0(FP), A0
-	MOV	ZERO, A1
-	MOV	$SYS_pipe2, A7
-	ECALL
-	MOVW	A0, errno+8(FP)
-	RET
-
 // func pipe2(flags int32) (r, w int32, errno int32)
 TEXT runtime·pipe2(SB),NOSPLIT|NOFRAME,$0-20
 	MOV	$r+8(FP), A0
@@ -635,21 +626,6 @@ TEXT runtime·closeonexec(SB),NOSPLIT|NOFRAME,$0
 	ECALL
 	RET
 
-// func runtime·setNonblock(int32 fd)
-TEXT runtime·setNonblock(SB),NOSPLIT|NOFRAME,$0-4
-	MOVW	fd+0(FP), A0 // fd
-	MOV	$3, A1	// F_GETFL
-	MOV	$0, A2
-	MOV	$SYS_fcntl, A7
-	ECALL
-	MOV	$0x800, A2 // O_NONBLOCK
-	OR	A0, A2
-	MOVW	fd+0(FP), A0 // fd
-	MOV	$4, A1	// F_SETFL
-	MOV	$SYS_fcntl, A7
-	ECALL
-	RET
-
 // func sbrk0() uintptr
 TEXT runtime·sbrk0(SB),NOSPLIT,$0-8
 	// Implemented as brk(NULL).

src/runtime/sys_linux_s390x.s

@@ -16,7 +16,6 @@
 #define SYS_close                 6
 #define SYS_getpid               20
 #define SYS_kill                 37
-#define SYS_pipe		 42
 #define SYS_brk			 45
 #define SYS_fcntl                55
 #define SYS_mmap                 90
@@ -103,14 +102,6 @@ TEXT runtime·read(SB),NOSPLIT|NOFRAME,$0-28
 	MOVW	R2, ret+24(FP)
 	RET
 
-// func pipe() (r, w int32, errno int32)
-TEXT runtime·pipe(SB),NOSPLIT|NOFRAME,$0-12
-	MOVD	$r+0(FP), R2
-	MOVW	$SYS_pipe, R1
-	SYSCALL
-	MOVW	R2, errno+8(FP)
-	RET
-
 // func pipe2() (r, w int32, errno int32)
 TEXT runtime·pipe2(SB),NOSPLIT|NOFRAME,$0-20
 	MOVD	$r+8(FP), R2
@@ -497,21 +488,6 @@ TEXT runtime·closeonexec(SB),NOSPLIT|NOFRAME,$0
 	SYSCALL
 	RET
 
-// func runtime·setNonblock(int32 fd)
-TEXT runtime·setNonblock(SB),NOSPLIT|NOFRAME,$0-4
-	MOVW	fd+0(FP), R2 // fd
-	MOVD	$3, R3	// F_GETFL
-	XOR	R4, R4
-	MOVW	$SYS_fcntl, R1
-	SYSCALL
-	MOVD	$0x800, R4 // O_NONBLOCK
-	OR	R2, R4
-	MOVW	fd+0(FP), R2 // fd
-	MOVD	$4, R3	// F_SETFL
-	MOVW	$SYS_fcntl, R1
-	SYSCALL
-	RET
-
 // func sbrk0() uintptr
 TEXT runtime·sbrk0(SB),NOSPLIT|NOFRAME,$0-8
 	// Implemented as brk(NULL).

src/runtime/sys_netbsd_386.s

@@ -87,21 +87,6 @@ TEXT runtime·read(SB),NOSPLIT,$-4
 	MOVL	AX, ret+12(FP)
 	RET
 
-// func pipe() (r, w int32, errno int32)
-TEXT runtime·pipe(SB),NOSPLIT,$0-12
-	MOVL	$42, AX
-	INT	$0x80
-	JCC	pipeok
-	MOVL	$-1, r+0(FP)
-	MOVL	$-1, w+4(FP)
-	MOVL	AX, errno+8(FP)
-	RET
-pipeok:
-	MOVL	AX, r+0(FP)
-	MOVL	DX, w+4(FP)
-	MOVL	$0, errno+8(FP)
-	RET
-
 // func pipe2(flags int32) (r, w int32, errno int32)
 TEXT runtime·pipe2(SB),NOSPLIT,$12-16
 	MOVL	$453, AX
@@ -484,20 +469,3 @@ TEXT runtime·closeonexec(SB),NOSPLIT,$32
 	JAE	2(PC)
 	NEGL	AX
 	RET
-
-// func runtime·setNonblock(fd int32)
-TEXT runtime·setNonblock(SB),NOSPLIT,$16-4
-	MOVL	$92, AX // fcntl
-	MOVL	fd+0(FP), BX // fd
-	MOVL	BX, 4(SP)
-	MOVL	$3, 8(SP) // F_GETFL
-	MOVL	$0, 12(SP)
-	INT	$0x80
-	MOVL	fd+0(FP), BX // fd
-	MOVL	BX, 4(SP)
-	MOVL	$4, 8(SP) // F_SETFL
-	ORL	$4, AX // O_NONBLOCK
-	MOVL	AX, 12(SP)
-	MOVL	$92, AX // fcntl
-	INT	$0x80
-	RET

src/runtime/sys_netbsd_amd64.s

@@ -163,21 +163,6 @@ TEXT runtime·read(SB),NOSPLIT,$-8
 	MOVL	AX, ret+24(FP)
 	RET
 
-// func pipe() (r, w int32, errno int32)
-TEXT runtime·pipe(SB),NOSPLIT,$0-12
-	MOVL	$42, AX
-	SYSCALL
-	JCC	pipeok
-	MOVL	$-1, r+0(FP)
-	MOVL	$-1, w+4(FP)
-	MOVL	AX, errno+8(FP)
-	RET
-pipeok:
-	MOVL	AX, r+0(FP)
-	MOVL	DX, w+4(FP)
-	MOVL	$0, errno+8(FP)
-	RET
-
 // func pipe2(flags int32) (r, w int32, errno int32)
 TEXT runtime·pipe2(SB),NOSPLIT,$0-20
 	LEAQ	r+8(FP), DI
@@ -449,18 +434,3 @@ TEXT runtime·closeonexec(SB),NOSPLIT,$0
 	MOVL	$SYS_fcntl, AX
 	SYSCALL
 	RET
-
-// func runtime·setNonblock(int32 fd)
-TEXT runtime·setNonblock(SB),NOSPLIT,$0-4
-	MOVL    fd+0(FP), DI  // fd
-	MOVQ    $3, SI  // F_GETFL
-	MOVQ    $0, DX
-	MOVL	$92, AX // fcntl
-	SYSCALL
-	MOVL	fd+0(FP), DI // fd
-	MOVQ	$4, SI // F_SETFL
-	MOVQ	$4, DX // O_NONBLOCK
-	ORL	AX, DX
-	MOVL	$92, AX // fcntl
-	SYSCALL
-	RET

src/runtime/sys_netbsd_arm.s

@@ -96,22 +96,6 @@ TEXT runtime·read(SB),NOSPLIT|NOFRAME,$0
 	MOVW	R0, ret+12(FP)
 	RET
 
-// func pipe() (r, w int32, errno int32)
-TEXT runtime·pipe(SB),NOSPLIT,$0-12
-	SWI $0xa0002a
-	BCC pipeok
-	MOVW $-1,R2
-	MOVW R2, r+0(FP)
-	MOVW R2, w+4(FP)
-	MOVW R0, errno+8(FP)
-	RET
-pipeok:
-	MOVW $0, R2
-	MOVW R0, r+0(FP)
-	MOVW R1, w+4(FP)
-	MOVW R2, errno+8(FP)
-	RET
-
 // func pipe2(flags int32) (r, w int32, errno int32)
 TEXT runtime·pipe2(SB),NOSPLIT,$0-16
 	MOVW $r+4(FP), R0
@@ -422,18 +406,6 @@ TEXT runtime·closeonexec(SB),NOSPLIT,$0
 	SWI $SYS_fcntl
 	RET
 
-// func runtime·setNonblock(fd int32)
-TEXT runtime·setNonblock(SB),NOSPLIT,$0-4
-	MOVW fd+0(FP), R0	// fd
-	MOVW $3, R1	// F_GETFL
-	MOVW $0, R2
-	SWI $0xa0005c	// sys_fcntl
-	ORR $0x4, R0, R2	// O_NONBLOCK
-	MOVW fd+0(FP), R0	// fd
-	MOVW $4, R1	// F_SETFL
-	SWI $0xa0005c	// sys_fcntl
-	RET
-
 // TODO: this is only valid for ARMv7+
 TEXT ·publicationBarrier(SB),NOSPLIT|NOFRAME,$0-0
 	B	runtime·armPublicationBarrier(SB)

src/runtime/sys_netbsd_arm64.s

@@ -154,17 +154,6 @@ ok:
 	MOVW	R0, ret+24(FP)
 	RET
 
-// func pipe() (r, w int32, errno int32)
-TEXT runtime·pipe(SB),NOSPLIT|NOFRAME,$0-12
-	ADD	$8, RSP, R0
-	MOVW	$0, R1
-	SVC	$SYS_pipe2
-	BCC	pipeok
-	NEG	R0, R0
-pipeok:
-	MOVW	R0, errno+8(FP)
-	RET
-
 // func pipe2(flags int32) (r, w int32, errno int32)
 TEXT runtime·pipe2(SB),NOSPLIT|NOFRAME,$0-20
 	ADD	$16, RSP, R0
@@ -466,16 +455,3 @@ TEXT runtime·closeonexec(SB),NOSPLIT,$0
 	MOVW	$FD_CLOEXEC, R2
 	SVC	$SYS_fcntl
 	RET
-
-// func runtime·setNonblock(int32 fd)
-TEXT runtime·setNonblock(SB),NOSPLIT|NOFRAME,$0-4
-	MOVW	fd+0(FP), R0		// arg 1 - fd
-	MOVD	$F_GETFL, R1		// arg 2 - cmd
-	MOVD	$0, R2			// arg 3
-	SVC	$SYS_fcntl
-	MOVD	$O_NONBLOCK, R2
-	EOR	R0, R2			// arg 3 - flags
-	MOVW	fd+0(FP), R0		// arg 1 - fd
-	MOVD	$F_SETFL, R1		// arg 2 - cmd
-	SVC	$SYS_fcntl
-	RET

src/runtime/sys_openbsd2.go

@@ -111,10 +111,6 @@ func write1(fd uintptr, p unsafe.Pointer, n int32) int32 {
 }
 func write_trampoline()
 
-func pipe() (r, w int32, errno int32) {
-	return pipe2(0)
-}
-
 func pipe2(flags int32) (r, w int32, errno int32) {
 	var p [2]int32
 	args := struct {
@@ -258,12 +254,6 @@ func closeonexec(fd int32) {
 	fcntl(fd, _F_SETFD, _FD_CLOEXEC)
 }
 
-//go:nosplit
-func setNonblock(fd int32) {
-	flags := fcntl(fd, _F_GETFL, 0)
-	fcntl(fd, _F_SETFL, flags|_O_NONBLOCK)
-}
-
 // Tell the linker that the libc_* functions are to be found
 // in a system library, with the libc_ prefix missing.
 

src/runtime/sys_openbsd_mips64.s

@@ -64,17 +64,6 @@ TEXT runtime·read(SB),NOSPLIT|NOFRAME,$0
 	MOVW	R2, ret+24(FP)
 	RET
 
-// func pipe() (r, w int32, errno int32)
-TEXT runtime·pipe(SB),NOSPLIT|NOFRAME,$0-12
-	MOVV	$r+0(FP), R4
-	MOVW	$0, R5
-	MOVV	$101, R2		// sys_pipe2
-	SYSCALL
-	BEQ	R7, 2(PC)
-	SUBVU	R2, R0, R2	// caller expects negative errno
-	MOVW	R2, errno+8(FP)
-	RET
-
 // func pipe2(flags int32) (r, w int32, errno int32)
 TEXT runtime·pipe2(SB),NOSPLIT|NOFRAME,$0-20
 	MOVV	$r+8(FP), R4
@@ -383,18 +372,3 @@ TEXT runtime·closeonexec(SB),NOSPLIT,$0
 	MOVV	$92, R2			// sys_fcntl
 	SYSCALL
 	RET
-
-// func runtime·setNonblock(int32 fd)
-TEXT runtime·setNonblock(SB),NOSPLIT|NOFRAME,$0-4
-	MOVW	fd+0(FP), R4		// arg 1 - fd
-	MOVV	$3, R5			// arg 2 - cmd (F_GETFL)
-	MOVV	$0, R6			// arg 3
-	MOVV	$92, R2			// sys_fcntl
-	SYSCALL
-	MOVV	$4, R6			// O_NONBLOCK
-	OR	R2, R6			// arg 3 - flags
-	MOVW	fd+0(FP), R4		// arg 1 - fd
-	MOVV	$4, R5			// arg 2 - cmd (F_SETFL)
-	MOVV	$92, R2			// sys_fcntl
-	SYSCALL
-	RET