<html><head><meta http-equiv="Content-Type" content="text/html charset=iso-8859-1"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><br><div><div>On Sep 28, 2012, at 9:45 AM, James Molloy <<a href="mailto:james@jamesmolloy.co.uk">james@jamesmolloy.co.uk</a>> wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><span style="font-family: Helvetica; font-size: medium; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; display: inline !important; float: none; ">You can easily simplify this problem with a restriction in SPIR: disallow ConstantExpr casts - no ptrtoint constant expression. Because GlobalVariables have pointer type, if you disallow converting their type to non-pointer type in a constantexpr, the number of constantexpr subclasses you have to deal with is drastically reduced (to essentially just BitCast and GEP).</span></blockquote></div><br><div>Wouldn't an easier solution just be not to represent them as constants in the first place? For instance, you could have a built-in function to get the address of local N, where N is taken as a parameter. You can call the builtins at the beginning of the kernel, and then proceed to use them as you wish without having to worry about reversing a constant folding later. Plus, if a given vendor's backend <i>wants</i> the address to get constant folded, it's easy to do replaceAllUsesWith of the call with a global, and run an appropriate constant folding pass.</div><div><br></div><div>--Owen</div></body></html>