runtime: merge lfstack{Pack,Unpack} into one file

Merge the remaining lfstack{Pack,Unpack} implemetations into one file.

unsafe.Sizeof(uintptr(0)) == 4 is a constant comparison so this branch
folds away at compile time.

Dmitry confirmed that the upper 17 bits of an address will be zero for a
user mode pointer, so there is no need to sign extend on amd64 during
unpack, so we can reuse the same implementation as all othe 64 bit
archs.

Change-Id: I99f589416d8b181ccde5364c9c2e78e4a5efc7f1
Reviewed-on: https://go-review.googlesource.com/21597
Run-TryBot: Dave Cheney <dave@cheney.net>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Minux Ma <minux@golang.org>

1 files changed, 0 insertions, 19 deletions

diff --git a/src/runtime/lfstack_32bit.go b/src/runtime/lfstack_32bit.go
deleted file mode 100644
index 2f59e0212e..0000000000
--- a/src/runtime/lfstack_32bit.go
+++ /dev/null
@@ -1,19 +0,0 @@
-// 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.
-
-// +build 386 arm nacl
-
-package runtime
-
-import "unsafe"
-
-// On 32-bit systems, the stored uint64 has a 32-bit pointer and 32-bit count.
-
-func lfstackPack(node *lfnode, cnt uintptr) uint64 {
-	return uint64(uintptr(unsafe.Pointer(node)))<<32 | uint64(cnt)
-}
-
-func lfstackUnpack(val uint64) *lfnode {
-	return (*lfnode)(unsafe.Pointer(uintptr(val >> 32)))
-}