<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><br><div><div>On Jan 16, 2012, at 11:35 PM, Jakob Stoklund Olesen 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 style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div><blockquote type="cite"><div class="gmail_quote"><blockquote class="gmail_quote" style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0.8ex; border-left-width: 1px; border-left-color: rgb(204, 204, 204); border-left-style: solid; padding-left: 1ex; position: static; z-index: auto; "><div class="im">><br>> This patch adds BitVector operations to efficiently apply literal bit<br>> masks specified as arrays of uint32_t. Since each array entry always<br>> holds exactly 32 bits, these portable bit masks can be source code<br>> literals, probably produced by TableGen.<br><br></div>Out of curiosity, why not arrays of uint64_t? It will be faster on 64-bit platforms, and shouldn't really be a penalty on 32-bit either.<br></blockquote></div></blockquote><div><br></div><div>It's a speed / size tradeoff. The typical use case is bit vectors of physical registers, which means a bit vector with 160 entries on x86. Using uint64_t would mean a 20% space overhead compared to uint32_t.</div></div></div></span><br class="Apple-interchange-newline"></blockquote></div><br><div>Ok! Thanks Jakob,</div><div><br></div><div>-Chris</div><div><br></div></body></html>