[pypy-svn] pypy jit-shadowstack: Uh, we don't need to clear the shadow stack's memory (which is

[arigo]

Author: Armin Rigo <arigo at tunes.org>
Branch: jit-shadowstack
Changeset: r43023:aa9a6e1e4778
Date: 2011-03-30 17:24 +0200
http://bitbucket.org/pypy/pypy/changeset/aa9a6e1e4778/

Log:	Uh, we don't need to clear the shadow stack's memory (which is
	important in case we create a lot of threads). It is going to
	contain random stuff anyway after a few pushes and pops. No code
	should access it past the root_stack_top limit, and (at least
	nowadays) the shadow stack is not emitted by genc but allocated
	dynamically.

diff --git a/pypy/rpython/memory/gctransform/framework.py b/pypy/rpython/memory/gctransform/framework.py
--- a/pypy/rpython/memory/gctransform/framework.py
+++ b/pypy/rpython/memory/gctransform/framework.py
@@ -1336,10 +1336,7 @@
         return top.address[0]
 
     def allocate_stack(self):
-        result = llmemory.raw_malloc(self.rootstacksize)
-        if result:
-            llmemory.raw_memclear(result, self.rootstacksize)
-        return result
+        return llmemory.raw_malloc(self.rootstacksize)
 
     def setup_root_walker(self):
         stackbase = self.allocate_stack()