[cfe-dev] Enhancing the DataFlowSolver in clang

[Simone Pellegrini]

On 07/20/2010 08:56 PM, Ted Kremenek wrote:
> On Jul 20, 2010, at 7:52 AM, Simone Pellegrini wrote:
>
>    
>> I run make tests from the root clang folder and none of the existing tests have been broken.
>>
>> In attachment the patch file with the fix to the DataFlowSolver.h
>>      
> I think this patch is mostly there, but the following assumes that ValTy is a bitvector:
>
> +		// if there the block value has been initialized, and this is the first
> +		// iteration, use the initialized value
> +		if(noEdges and !D.getBlockDataMap()[B].sizesEqual(ValTy()))
> +			Merge(V, D.getBlockDataMap()[B]);
>
> 'sizesEqual' should not appear anywhere in DataSolver.h.  The solver needs to be generic to not assume specific details of ValTy.
>    
Hello again,
I removed the sizesEqual check. Now, I just search for the block B in 
the map, if there is no entry in the BlockDataMap it means the user 
didn't provide any initialization. In this way we didn't assume any 
specific detail of ValTy.
> A performance nit: here 'getBlockDataMap()' is called twice.  That's wasteful as it requires two lookups in the hashtable instead of one.
>    
I also optimized the code by reducing the number of lookups to 1.
> Also, please use spaces instead of tabs.
ok.

cheers, Simone
-------------- next part --------------
A non-text attachment was scrubbed...
Name: DataFlowSolver.patch
Type: text/x-patch
Size: 1511 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/cfe-dev/attachments/20100721/6d8e97e7/attachment.bin>