[dev.cc] runtime: convert parallel support code from C to Go

The conversion was done with an automated tool and then
modified only as necessary to make it compile and run.

[This CL is part of the removal of C code from package runtime.
See golang.org/s/dev.cc for an overview.]

LGTM=r
R=r, austin
CC=dvyukov, golang-codereviews, iant, khr
https://golang.org/cl/172250043

1 files changed, 0 insertions, 87 deletions

diff --git a/src/runtime/lfstack.c b/src/runtime/lfstack.c
deleted file mode 100644
index 57e0af2829..0000000000
--- a/src/runtime/lfstack.c
+++ /dev/null
@@ -1,87 +0,0 @@
-// Copyright 2012 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.
-
-// Lock-free stack.
-// The following code runs only on g0 stack.
-
-#include "runtime.h"
-#include "arch_GOARCH.h"
-
-#ifdef _64BIT
-// Amd64 uses 48-bit virtual addresses, 47-th bit is used as kernel/user flag.
-// So we use 17msb of pointers as ABA counter.
-# define PTR_BITS 47
-#else
-# define PTR_BITS 32
-#endif
-#define PTR_MASK ((1ull<<PTR_BITS)-1)
-#define CNT_MASK (0ull-1)
-
-#ifdef _64BIT
-#ifdef GOOS_solaris
-// SPARC64 and Solaris on AMD64 uses all 64 bits of virtual addresses.
-// Use low-order three bits as ABA counter.
-// http://docs.oracle.com/cd/E19120-01/open.solaris/816-5138/6mba6ua5p/index.html
-#undef PTR_BITS
-#undef CNT_MASK
-#undef PTR_MASK
-#define PTR_BITS 0
-#define CNT_MASK 7
-#define PTR_MASK ((0ull-1)<<3)
-#endif
-#endif
-
-void
-runtime·lfstackpush(uint64 *head, LFNode *node)
-{
-	uint64 old, new;
-
-	if((uintptr)node != ((uintptr)node&PTR_MASK)) {
-		runtime·printf("p=%p\n", node);
-		runtime·throw("runtime·lfstackpush: invalid pointer");
-	}
-
-	node->pushcnt++;
-	new = (uint64)(uintptr)node|(((uint64)node->pushcnt&CNT_MASK)<<PTR_BITS);
-	for(;;) {
-		old = runtime·atomicload64(head);
-		node->next = (LFNode*)(uintptr)(old&PTR_MASK);
-		if(runtime·cas64(head, old, new))
-			break;
-	}
-}
-
-LFNode*
-runtime·lfstackpop(uint64 *head)
-{
-	LFNode *node, *node2;
-	uint64 old, new;
-
-	for(;;) {
-		old = runtime·atomicload64(head);
-		if(old == 0)
-			return nil;
-		node = (LFNode*)(uintptr)(old&PTR_MASK);
-		node2 = runtime·atomicloadp(&node->next);
-		new = 0;
-		if(node2 != nil)
-			new = (uint64)(uintptr)node2|(((uint64)node2->pushcnt&CNT_MASK)<<PTR_BITS);
-		if(runtime·cas64(head, old, new))
-			return node;
-	}
-}
-
-void
-runtime·lfstackpush_m(void)
-{
-	runtime·lfstackpush(g->m->ptrarg[0], g->m->ptrarg[1]);
-	g->m->ptrarg[0] = nil;
-	g->m->ptrarg[1] = nil;
-}
-
-void
-runtime·lfstackpop_m(void)
-{
-	g->m->ptrarg[0] = runtime·lfstackpop(g->m->ptrarg[0]);
-}