<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><br><div><div>On Dec 18, 2009, at 12:15 PM, Victor Hernandez wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><br><div><div>On Dec 17, 2009, at 12:06 AM, Chris Lattner wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><span class="Apple-style-span" style="border-collapse: separate; font-family: Helvetica; font-size: medium; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><div>On Dec 16, 2009, at 10:56 AM, Devang Patel wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><span class="Apple-style-span" style="border-collapse: separate; font-family: Helvetica; font-size: medium; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><blockquote type="cite"><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div><blockquote type="cite"><div><br>Is this new field copied by MetadataContextImpl::copyMD?<font class="Apple-style-span"><font class="Apple-style-span" color="#144FAE"><br></font></font></div></blockquote><div><div><br></div><div>The semantic is that if an MDNode is created function-local, then it will continue to be function-local even if its operands are modified to no longer refer to any function-specific IR.</div></div></div></div></blockquote><div><br></div><div>That'll break MDNode unique-ness.</div></span></blockquote><div><br></div>We don't guarantee MDNode uniqueness, we just endeavor to preserve it when it isn't "too hard".</span></blockquote></div><br><div>Devang, you were concerned that 2 MDNodes with identical operands would not be the same if one is function-local and the other is not (can happen if an originally function-local MDNode has its operands modified to match those of a pre-existing non-function-local MDNode). Are there any issues with making these MDNodes be distinct?</div></div></blockquote><div><br></div>Again, as Dan asked earlier, what's the use ? IMO, verifier needs are not at all "too hard" in this case. As Chris agreed, we can have one utility routine to satisfy verifier's needs. I do not see any need to 1) add Function * in MDNode, 2) or add a bit in MDNode, 3) or extend MDNode class hierarchy, just for verifier. Let's focus on completing @llvm.dbg.var support and we can revisit this when there is a real need.</div><div><br></div><div>-</div><div>Devan</div></body></html>