<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><br><div><div>On Sep 12, 2011, at 2:22 AM, Chandler Carruth wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><span class="Apple-style-span" style="border-collapse: separate; font-family: Helvetica; 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-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; font-size: medium; "><div>I think this patch is a really useful improvement in accuracy, but it does add some non-trivial overhead to the process of adding implicit destructors into the CFG for automatic variables.. Does it seem acceptable? I don't see particularly cleaner ways of doing this... =/</div></span></blockquote><div><br></div><div>I think this is a reasonable approach.</div><div><br></div><div>By non-trivial overhead, are you talking about something that is actually measurable in terms of -fsyntax-only time? Do you have any numbers?</div><div><br></div><blockquote type="cite"><span class="Apple-style-span" style="border-collapse: separate; font-family: Helvetica; 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-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; font-size: medium; "><div><br></div><div>If this patch is OK, or after any performance tuning you'd like to see here, I think I also better understand the FIXME in the analysis file. Do you actually want to switch the CFG to have *no* successors for blocks which contain a no-return element?<span class="Apple-converted-space"> </span></div></span></blockquote></div><br><div>No at all. That's definitely not the invariant we are going for. We want all blocks to be reverse-reachable from the exit block. This is needed for servicing reverse dataflow analyses.</div></body></html>