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["Adve, Vikram Sadanand" <vadve AT illinois.edu>]

Ah, John is right.  I don't know how I missed that... The theoretical 
requirements is that the pools at run-time must be at least as precise as the 
points-to sets computed by DSA(*), otherwise the soundness of pointer 
analysis or type information on DS nodes is not guaranteed.  The single 
global pool of course is less precise than DSA.

(*) More precisely, for every pair of DS nodes, n1 and n2, there must be no 
runtime pool instance that holds objects from both n1 and n2.  I.e., there 
must be a 1-many mapping of DS nodes to pool instances.

--Vikram
Associate Professor, Computer Science
University of Illinois at Urbana-Champaign
http://llvm.org/~vadve



On Mar 11, 2010, at 3:11 PM, John Criswell wrote:

> However, SAFECode's guarantee that pointers always access objects in the 
> correct points-to set (as computed by DSA) can be violated.  This is 
> because the PASimple.cpp pass does not correctly merge all nodes in the 
> points-to graph into a single node.  While a program is guaranteed to 
> access an object of the expected type, that object may belong to a 
> different points-to set than what DSA determined.