DSGraph questions

I'll try to answer these because Chris is really busy this week.

From: Xiaodong Li <xli3@santoor.cs.uiuc.edu>
Subject: [LLVMdev] DSGraph questions
Sender: llvmdev-admin@cs.uiuc.edu
Date: Sun, 10 Nov 2002 11:25:53 -0600 (CST)

1. What is the difference between DSNodeHandle and DSNode? What do the
functions getLink() and getSize() do?

DSNodeHandle is essentially like an edge in the DSGraph.
It serves two main purposes:
(1) It keeps track of which byte offset is being pointed to within
    the target node.
(2) It keeps track of how many objects have pointers to a DSNode,
    so that it can check if the number is zero and free a node
    (reference counting)

getLink(Offset) returns the outgoing edge at byte offset "Offset"
from the current node. (think of each node as a struct, so there
can be pointers at different byte offsets within the struct.)

getSize() returns the max #bytes for any object folded into this node.

2. In the previous email, you mentioned that we can use
DSNode::getPointerSize() to get the number of links, But I checked the
doxygen documentation, there is no such member for DSNode.

Check the header file. The doxygen docs were a little out of date
(but Chris has updated them now).

3. Previously I use the following code:
for( df_iterator<DSNode*> I = df_begin(pnode), E=df_end(pnode); I!=E; ++i)
  ... ;
and got lots of error messages when I compile. And the reply was:
>What is the type of pnode? Guessing from the error message, I would think
>it's a 'const DSNode*'. You need to use either df_iterator<const DSNode*>
>or a DSNode* argument, you can't mix them.

I checked and found out that I was using
DSNode *pnode = dsg->getNodeforValue(fi).getNode() to get pnode.
So I think it's a DSNode.

I would have to see the error messages. In generally, if you have any
const variables or functions, you will get lots of error messages unless
you use them very carefully.


Dear Prof. Adve,

I recently checked out the llvm using
cvs update
command under the llvm directory. But when I went to see the DSNode.h,
there is no getPointerSize function. I checked the doxygen tree, it's
there. So that means I didn't update my cvs tree correctly. Could you let
me know how to update my CVS tree? Or there is a problem at somewhere


Sorry, it was not yet in the CSIL tree. I've updated it now.