runtime,reflect: clean duplicate definitions runtimeSelect

src/cmd/internal/objabi/pkgspecial.go

@@ -57,6 +57,8 @@ var runtimePkgs = []string{
 	"internal/godebugs",
 	"internal/goexperiment",
 	"internal/goos",
+
+	"internal/runtime/rchan",
 }
 
 // extraNoInstrumentPkgs is the set of packages in addition to runtimePkgs that

src/go/build/deps_test.go

@@ -54,7 +54,7 @@ var depsRules = `
 	internal/goarch, unsafe
 	< internal/abi, internal/chacha8rand;
 
-	unsafe < maps;
+	unsafe < maps, internal/runtime/rchan;
 
 	# RUNTIME is the core runtime group of packages, all of them very light-weight.
 	internal/abi,
@@ -63,6 +63,7 @@ var depsRules = `
 	internal/cpu,
 	internal/goarch,
 	internal/godebugs,
+	internal/runtime/rchan,
 	internal/goexperiment,
 	internal/goos
 	< internal/bytealg
@@ -189,7 +190,7 @@ var depsRules = `
 
 	# FMT is OS (which includes string routines) plus reflect and fmt.
 	# It does not include package log, which should be avoided in core packages.
-	arena, strconv, unicode
+	arena, strconv, unicode, internal/runtime/rchan
 	< reflect;
 
 	os, reflect

src/internal/runtime/rchan/select.go

@@ -0,0 +1,27 @@
+// Copyright 2024 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.
+
+package rchan
+
+import (
+	"unsafe"
+)
+
+// A Select is a single case passed to rselect.
+type Select struct {
+	Dir SelectDir
+	Typ unsafe.Pointer // channel type (not used here)
+	Ch  unsafe.Pointer // channel
+	Val unsafe.Pointer // ptr to data (SendDir) or ptr to receive buffer (RecvDir)
+}
+
+// These values must match ../reflect/value.go:/SelectDir.
+type SelectDir int
+
+const (
+	_             SelectDir = iota
+	SelectSend              // case Chan <- Send
+	SelectRecv              // case <-Chan:
+	SelectDefault           // default
+)

src/reflect/value.go

@@ -9,6 +9,7 @@ import (
 	"internal/abi"
 	"internal/goarch"
 	"internal/itoa"
+	"internal/runtime/rchan"
 	"internal/unsafeheader"
 	"math"
 	"runtime"
@@ -3015,15 +3016,6 @@ func Copy(dst, src Value) int {
 	return typedslicecopy(de.Common(), ds, ss)
 }
 
-// A runtimeSelect is a single case passed to rselect.
-// This must match ../runtime/select.go:/runtimeSelect
-type runtimeSelect struct {
-	dir SelectDir      // SelectSend, SelectRecv or SelectDefault
-	typ *rtype         // channel type
-	ch  unsafe.Pointer // channel
-	val unsafe.Pointer // ptr to data (SendDir) or ptr to receive buffer (RecvDir)
-}
-
 // rselect runs a select. It returns the index of the chosen case.
 // If the case was a receive, val is filled in with the received value.
 // The conventional OK bool indicates whether the receive corresponds
@@ -3035,7 +3027,7 @@ type runtimeSelect struct {
 // that with a forced escape in function Select.
 //
 //go:noescape
-func rselect([]runtimeSelect) (chosen int, recvOK bool)
+func rselect([]rchan.Select) (chosen int, recvOK bool)
 
 // A SelectDir describes the communication direction of a select case.
 type SelectDir int
@@ -3086,19 +3078,19 @@ func Select(cases []SelectCase) (chosen int, recv Value, recvOK bool) {
 	// NOTE: Do not trust that caller is not modifying cases data underfoot.
 	// The range is safe because the caller cannot modify our copy of the len
 	// and each iteration makes its own copy of the value c.
-	var runcases []runtimeSelect
+	var runcases []rchan.Select
 	if len(cases) > 4 {
 		// Slice is heap allocated due to runtime dependent capacity.
-		runcases = make([]runtimeSelect, len(cases))
+		runcases = make([]rchan.Select, len(cases))
 	} else {
 		// Slice can be stack allocated due to constant capacity.
-		runcases = make([]runtimeSelect, len(cases), 4)
+		runcases = make([]rchan.Select, len(cases), 4)
 	}
 
 	haveDefault := false
 	for i, c := range cases {
 		rc := &runcases[i]
-		rc.dir = c.Dir
+		rc.Dir = rchan.SelectDir(c.Dir)
 		switch c.Dir {
 		default:
 			panic("reflect.Select: invalid Dir")
@@ -3126,22 +3118,22 @@ func Select(cases []SelectCase) (chosen int, recv Value, recvOK bool) {
 			if ChanDir(tt.Dir)&SendDir == 0 {
 				panic("reflect.Select: SendDir case using recv-only channel")
 			}
-			rc.ch = ch.pointer()
-			rc.typ = toRType(&tt.Type)
+			rc.Ch = ch.pointer()
+			rc.Typ = (unsafe.Pointer)(&tt.Type)
 			v := c.Send
 			if !v.IsValid() {
 				panic("reflect.Select: SendDir case missing Send value")
 			}
 			v.mustBeExported()
 			v = v.assignTo("reflect.Select", tt.Elem, nil)
 			if v.flag&flagIndir != 0 {
-				rc.val = v.ptr
+				rc.Val = v.ptr
 			} else {
-				rc.val = unsafe.Pointer(&v.ptr)
+				rc.Val = unsafe.Pointer(&v.ptr)
 			}
 			// The value to send needs to escape. See the comment at rselect for
 			// why we need forced escape.
-			escapes(rc.val)
+			escapes(rc.Val)
 
 		case SelectRecv:
 			if c.Send.IsValid() {
@@ -3157,17 +3149,17 @@ func Select(cases []SelectCase) (chosen int, recv Value, recvOK bool) {
 			if ChanDir(tt.Dir)&RecvDir == 0 {
 				panic("reflect.Select: RecvDir case using send-only channel")
 			}
-			rc.ch = ch.pointer()
-			rc.typ = toRType(&tt.Type)
-			rc.val = unsafe_New(tt.Elem)
+			rc.Ch = ch.pointer()
+			rc.Typ = (unsafe.Pointer)(&tt.Type)
+			rc.Val = unsafe_New(tt.Elem)
 		}
 	}
 
 	chosen, recvOK = rselect(runcases)
-	if runcases[chosen].dir == SelectRecv {
-		tt := (*chanType)(unsafe.Pointer(runcases[chosen].typ))
+	if runcases[chosen].Dir == rchan.SelectDir(SelectRecv) {
+		tt := (*chanType)(unsafe.Pointer(runcases[chosen].Typ))
 		t := tt.Elem
-		p := runcases[chosen].val
+		p := runcases[chosen].Val
 		fl := flag(t.Kind())
 		if t.IfaceIndir() {
 			recv = Value{t, p, fl | flagIndir}

src/runtime/select.go

@@ -8,6 +8,7 @@ package runtime
 
 import (
 	"internal/abi"
+	"internal/runtime/rchan"
 	"unsafe"
 )
 
@@ -519,27 +520,8 @@ func (c *hchan) sortkey() uintptr {
 	return uintptr(unsafe.Pointer(c))
 }
 
-// A runtimeSelect is a single case passed to rselect.
-// This must match ../reflect/value.go:/runtimeSelect
-type runtimeSelect struct {
-	dir selectDir
-	typ unsafe.Pointer // channel type (not used here)
-	ch  *hchan         // channel
-	val unsafe.Pointer // ptr to data (SendDir) or ptr to receive buffer (RecvDir)
-}
-
-// These values must match ../reflect/value.go:/SelectDir.
-type selectDir int
-
-const (
-	_             selectDir = iota
-	selectSend              // case Chan <- Send
-	selectRecv              // case <-Chan:
-	selectDefault           // default
-)
-
 //go:linkname reflect_rselect reflect.rselect
-func reflect_rselect(cases []runtimeSelect) (int, bool) {
+func reflect_rselect(cases []rchan.Select) (int, bool) {
 	if len(cases) == 0 {
 		block()
 	}
@@ -549,19 +531,19 @@ func reflect_rselect(cases []runtimeSelect) (int, bool) {
 	dflt := -1
 	for i, rc := range cases {
 		var j int
-		switch rc.dir {
-		case selectDefault:
+		switch rc.Dir {
+		case rchan.SelectDefault:
 			dflt = i
 			continue
-		case selectSend:
+		case rchan.SelectSend:
 			j = nsends
 			nsends++
-		case selectRecv:
+		case rchan.SelectRecv:
 			nrecvs++
 			j = len(cases) - nrecvs
 		}
 
-		sel[j] = scase{c: rc.ch, elem: rc.val}
+		sel[j] = scase{c: (*hchan)(rc.Ch), elem: rc.Val}
 		orig[j] = i
 	}