Re: [PATCH 3/4] sparse, llvm: base load/store address type on insn_symbol_type()

["Jonathan Neuschäfer" <j.neuschaefer@gmx.net>]

On Sat, May 18, 2013 at 06:45:18PM -0400, Xi Wang wrote:
> On 05/18/2013 01:52 PM, Jonathan Neuschäfer wrote:
> >   	/* convert address back to pointer */
> > -	addr = LLVMBuildIntToPtr(fn->builder, addr_i,
> > -				 LLVMTypeOf(src_p), "addr");
> > +	addr = LLVMBuildIntToPtr(fn->builder, addr_i, addr_type, "addr");
> 
> Actually, we shouldn't convert pointers to integers in the first place.
> This effectively disables pointer analysis and future optimizations.
> 
> A better way is to use LLVM's GEP for pointer arithmetic, by converting
> pointers to `char *', rather than integers.
> 
> See more examples here:
> http://www.spinics.net/lists/linux-sparse/msg02768.html
> 
> Jonathan, how about this version using `char *' based on your patchset?

It looks good. ACK.

> +	LLVMTypeRef type = LLVMTypeOf(base);
> +	unsigned int as = LLVMGetPointerAddressSpace(type);

Right, I was sloppy about address spaces. :-)


Thanks,
Jonathan
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