<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div><div>On Jan 21, 2011, at 11:09 PM, Lu Mitnick wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div>I am adding a new target into LLVM. However there is a assembler for that target and I just want LLVM to generate assembly. I read the document "Writing an LLVM Backend". I am wondering to know whether I can ignore the Inst field in the following example:</div>
<div><font class="Apple-style-span" face="monospace"><span class="Apple-style-span" style="white-space: pre; font-size: medium;"><font class="Apple-style-span" face="arial"><span class="Apple-style-span" style="white-space: normal; font-size: small;"><br>
</span></font></span></font></div><div><span class="Apple-style-span" style="font-family: monospace; font-size: medium; white-space: pre; ">class InstSP<dag outs, dag ins, string asmstr, list<dag> pattern> : Instruction {</span></div>
<span class="Apple-style-span" style="font-family: Times; font-size: medium; "><pre> field bits<32> Inst;
let Namespace = "SP";
bits<2> op;
let Inst{31-30} = op;
dag OutOperandList = outs;
dag InOperandList = ins;
let AsmString = asmstr;
let Pattern = pattern;
}</pre><pre>And define the instruction class of ported target as:</pre><pre><span class="Apple-style-span" style="font-family: arial; white-space: normal; font-size: small; "><div><span class="Apple-style-span" style="font-family: monospace; font-size: medium; white-space: pre; ">class Instxxx<dag outs, dag ins, string asmstr, list<dag> pattern> : Instruction {</span></div>
<span class="Apple-style-span" style="font-family: Times; font-size: medium; "><pre> let Namespace = "xxx";
dag OutOperandList = outs;
dag InOperandList = ins;
let AsmString = asmstr;
let Pattern = pattern;
}</pre></span></span></pre></span></blockquote><div>Hi Yi-Hong,</div><div><br></div><div>Yes, you may go ahead and omit the Inst field. That's used to represent the instruction encoding.</div></div><br><div>-bw</div><div><br></div></body></html>