<HTML><BODY style="word-wrap: break-word; -khtml-nbsp-mode: space; -khtml-line-break: after-white-space; "><BR><DIV><DIV>On Mar 30, 2007, at 12:30 PM, Devang Patel wrote:</DIV><BR class="Apple-interchange-newline"><BLOCKQUOTE type="cite"><BR><DIV><DIV>On Mar 30, 2007, at 10:29 AM, Christopher Lamb wrote:</DIV><BR class="Apple-interchange-newline"><BLOCKQUOTE type="cite"><SPAN class="Apple-style-span" style="border-collapse: separate; border-spacing: 0px 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-align: auto; -khtml-text-decorations-in-effect: none; text-indent: 0px; -apple-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><BLOCKQUOTE type="cite"><DIV style="color: rgb(0, 0, 221); "><DIV style="color: rgb(0, 0, 221); "><SPAN class="Apple-style-span" style="color: rgb(0, 0, 221); ">1) Update LLVM LD/ST instructions to maintain alignment information</SPAN></DIV></DIV></BLOCKQUOTE><DIV><BR class="khtml-block-placeholder"></DIV><DIV>Is this referring to the language itself, i.e. the bytecode/assembly format and associated readers/writers? If so this is probably the portion that it's most likely I could help with.</DIV><BR class="Apple-interchange-newline"></SPAN></BLOCKQUOTE></DIV><BR><DIV>Yes.</DIV></BLOCKQUOTE></DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>For the assembly format I assume that it would be a simple optional comma delimited alignment parameter at the end of the instruction, such as:</DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>%tmp5 = load i32* %tmp4, align 4</DIV><DIV>store i32 %val, i32* %tmp3, align 4</DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>Has the format for the extension of the load/store bytecode been determined? This would need to be applied to both normal and volatile load/store instructions, and I see three options.</DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>1. Add the ability to encode optional arguments on any load/store and volatile variants. This is general, but I can see why it could be bad given how frequent load/stores tend to be. Perhaps this is why pseudo ops were chosen for the volatile versions?</DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>2. Create pseudo opcodes for the permutations of volatility and alignment. This will consume 4 more opcodes, but it would not bloat the bytecode when natural alignment is used.</DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>3. Create pseudo ops for 'attributed' load/store instructions. These instructions contain a set of optional attributes encoded in some way. The current volatile load/store instructions could be subsumed by these instructions.</DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>I'm leaning away from 1, but unsure whether 2 or 3 is better.</DIV><DIV><BR class="khtml-block-placeholder"></DIV>Thanks<BR><DIV> <SPAN class="Apple-style-span" style="border-collapse: separate; border-spacing: 0px 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-align: auto; -khtml-text-decorations-in-effect: none; text-indent: 0px; -apple-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><SPAN class="Apple-style-span" style="border-collapse: separate; border-spacing: 0px 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-align: auto; -khtml-text-decorations-in-effect: none; text-indent: 0px; -apple-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><DIV>--</DIV><DIV>Christopher Lamb</DIV><DIV><BR class="khtml-block-placeholder"></DIV><BR class="Apple-interchange-newline"></SPAN></SPAN> </DIV><BR></BODY></HTML>