[LLVMdev] API CHANGE: Contexts for Passes

[Owen Anderson]

Hey folks,

As a number of people have observed, the current mechanism for  
providing an LLVMContext to each pass is extremely hackish, and tends  
to break down in lots of interesting ways.  In light of this, I've  
decided to drop the automagical nature of this mechanism.  Because  
types now hold references to contexts, it is now trivial to get a  
context from within a pass, and I am adding a getContext() accessor to  
Value to make it even simpler.

Summary:  The Context member of Pass will be going away.  Please fetch  
a context from a Type or Value instead.

--Owen