runtime: move stubs.goc code into runtime.c

Now that the calling conventions are the same,
there's no danger to using plain C for these.

LGTM=bradfitz
R=golang-codereviews, bradfitz
CC=dvyukov, golang-codereviews, iant, khr, r
https://golang.org/cl/134580043

src/pkg/runtime/runtime.c

@@ -341,3 +341,51 @@ runtime·timediv(int64 v, int32 div, int32 *rem)
 		*rem = v;
 	return res;
 }
+
+// Helpers for Go. Must be NOSPLIT, must only call NOSPLIT functions, and must not block.
+
+#pragma textflag NOSPLIT
+G*
+runtime·getg(void)
+{
+	return g;
+}
+
+#pragma textflag NOSPLIT
+M*
+runtime·acquirem(void)
+{
+	g->m->locks++;
+	return g->m;
+}
+
+#pragma textflag NOSPLIT
+void
+runtime·releasem(M *mp)
+{
+	mp->locks--;
+	if(mp->locks == 0 && g->preempt) {
+		// restore the preemption request in case we've cleared it in newstack
+		g->stackguard0 = StackPreempt;
+	}
+}
+
+#pragma textflag NOSPLIT
+MCache*
+runtime·gomcache(void)
+{
+	return g->m->mcache;
+}
+
+#pragma textflag NOSPLIT
+Slice
+reflect·typelinks(void)
+{
+	extern Type *runtime·typelink[], *runtime·etypelink[];
+	Slice ret;
+
+	ret.array = (byte*)runtime·typelink;
+	ret.len = runtime·etypelink - runtime·typelink;
+	ret.cap = ret.len;
+	return ret;
+}

src/pkg/runtime/stubs.goc

-// Copyright 2014 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 runtime
-#include "runtime.h"
-#include "arch_GOARCH.h"
-#include "malloc.h"
-#include "stack.h"
-#include "textflag.h"
-
-// This file contains functions called by Go but written
-// in C.  These functions are problematic for the garbage
-// collector and stack copier because we don't have
-// stack maps for them.  So we must ensure that the
-// garbage collector and stack copier cannot see these
-// frames.  So we impose the following invariants:
-
-// 1) Functions should be marked NOSPLIT and call
-//    out to only NOSPLIT functions (recursively).
-// 2) Functions should not block.
-
-// These invariants do not hold yet but will be established once we have
-// finished converting runtime support code from C to Go.
-
-#pragma textflag NOSPLIT
-func runtime·getg() (ret *G) {
-	ret = g;
-}
-
-#pragma textflag NOSPLIT
-func runtime·acquirem() (ret *M) {
-	ret = g->m;
-	ret->locks++;
-}
-
-#pragma textflag NOSPLIT
-func runtime·releasem(mp *M) {
-	mp->locks--;
-	if(mp->locks == 0 && g->preempt) {
-		// restore the preemption request in case we've cleared it in newstack
-		g->stackguard0 = StackPreempt;
-	}
-}
-
-#pragma textflag NOSPLIT
-func runtime·gomcache() (ret *MCache) {
-	ret = g->m->mcache;
-}
-
-#pragma textflag NOSPLIT
-func reflect·typelinks() (ret Slice) {
-        extern Type *runtime·typelink[], *runtime·etypelink[];
-        ret.array = (byte*)runtime·typelink;
-        ret.len = runtime·etypelink - runtime·typelink;
-        ret.cap = ret.len;
-}