<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:st1="urn:schemas-microsoft-com:office:smarttags" xmlns="http://www.w3.org/TR/REC-html40">
<head>
<meta http-equiv=Content-Type content="text/html; charset=us-ascii">
<meta name=Generator content="Microsoft Word 11 (filtered medium)">
<!--[if !mso]>
<style>
v\:* {behavior:url(#default#VML);}
o\:* {behavior:url(#default#VML);}
w\:* {behavior:url(#default#VML);}
.shape {behavior:url(#default#VML);}
</style>
<![endif]--><o:SmartTagType
namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="PersonName"/>
<!--[if !mso]>
<style>
st1\:*{behavior:url(#default#ieooui) }
</style>
<![endif]-->
<style>
<!--
/* Font Definitions */
@font-face
{font-family:"MS Mincho";
panose-1:2 2 6 9 4 2 5 8 3 4;}
@font-face
{font-family:Tahoma;
panose-1:2 11 6 4 3 5 4 4 2 4;}
@font-face
{font-family:"\@MS Mincho";
panose-1:2 2 6 9 4 2 5 8 3 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:"Times New Roman";}
a:link, span.MsoHyperlink
{color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{color:purple;
text-decoration:underline;}
span.EmailStyle18
{mso-style-type:personal-reply;
font-family:Arial;
color:navy;}
@page Section1
{size:8.5in 11.0in;
margin:1.0in 1.25in 1.0in 1.25in;}
div.Section1
{page:Section1;}
-->
</style>
</head>
<body lang=EN-US link=blue vlink=purple style='word-wrap: break-word;
-webkit-nbsp-mode: space;-webkit-line-break: after-white-space'>
<div class=Section1>
<p class=MsoNormal><font size=2 color=navy face=Arial><span lang=FR
style='font-size:10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<div>
<div class=MsoNormal align=center style='text-align:center'><font size=3
face="Times New Roman"><span style='font-size:12.0pt'>
<hr size=2 width="100%" align=center tabindex=-1>
</span></font></div>
<p class=MsoNormal><b><font size=2 face=Tahoma><span style='font-size:10.0pt;
font-family:Tahoma;font-weight:bold'>From:</span></font></b><font size=2
face=Tahoma><span style='font-size:10.0pt;font-family:Tahoma'>
llvmdev-bounces@cs.uiuc.edu [mailto:llvmdev-bounces@cs.uiuc.edu] <b><span
style='font-weight:bold'>On Behalf Of </span></b>Chris Lattner<br>
<b><span style='font-weight:bold'>Sent:</span></b> Friday, September 19, 2008
10:49 AM<br>
<b><span style='font-weight:bold'>To:</span></b> <st1:PersonName w:st="on">LLVM
Developers Mailing List</st1:PersonName><br>
<b><span style='font-weight:bold'>Subject:</span></b> Re: [LLVMdev] Custom
Opcodes versus built-in opcodes</span></font><o:p></o:p></p>
</div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
<div>
<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>On Sep 18, 2008, at 4:04 PM, Villmow, Micah wrote:<o:p></o:p></span></font></p>
</div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><br>
<br>
<o:p></o:p></span></font></p>
<span style='orphans: 2;text-align:auto;widows: 2;-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: 0;word-spacing:0px'><u1:smarttagtype namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="Street"><u1:smarttagtype namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="address"><u1:smarttagtype namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="City"><u1:smarttagtype namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="place">
<div link=blue vlink=purple>
<div>
<div>
<p class=MsoNormal><font size=2 color=black face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:black'>I am using lowering instructions and
using custom opcodes that I can more easily directly map to my backend. These
opcodes are then used to emit a custom set of instructions into the
MachineBasicBlock. I’ve been able to get one to work correctly, however, I’ve
ran into an issue where my second one is being confused as a FRAMEADDR opcode
instead of my opcode.</span></font><font color=black><span style='color:black'><o:p></o:p></span></font></p>
</div>
</div>
</div>
</span></u1:smarttagtype></u1:smarttagtype></u1:smarttagtype></u1:smarttagtype>
<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
</div>
<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>Make sure to use DAG.getTargetNode() with custom opcodes.
"target" nodes are encoded with an implicit delta added to
their enum value.<o:p></o:p></span></font></p>
</div>
<div>
<p class=MsoNormal><font size=3 color=navy face="Times New Roman"><span
style='font-size:12.0pt;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Is this documented anywhere that
getTargetNode is the preferred method to use in a Custom Lowering function?
Even the other backends use getNode in their lowering functions with custom
opcodes.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>This is from SparcISelLowering.cpp<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>CompareFlag = DAG.getNode(SPISD::CMPFCC,
MVT::Flag, LHS, RHS);<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'> if (SPCC == ~0U) SPCC =
FPCondCCodeToFCC(CC);<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'> Opc = SPISD::BRFCC;<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'> }<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'> return DAG.getNode(Opc, MVT::Other,
Chain, Dest,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>
</span></font><font size=2 color=navy face=Arial><span lang=FR
style='font-size:10.0pt;font-family:Arial;color:navy'>DAG.getConstant(SPCC,
MVT::i32), CompareFlag);<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span lang=FR
style='font-size:10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span lang=FR
style='font-size:10.0pt;font-family:Arial;color:navy'>Micah<o:p></o:p></span></font></p>
</div>
<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
</div>
</div>
</div>
</body>
</html>