<div dir="ltr"><span class="" style="border-collapse:collapse;font-family:Arial,'Liberation Sans','DejaVu Sans',sans-serif;font-size:14px;line-height:18px;color:rgb(0,0,0)"><p style="margin-top:0px;margin-right:0px;margin-bottom:1em;margin-left:0px;padding-top:0px;padding-right:0px;padding-bottom:0px;padding-left:0px;border-top-width:0px;border-right-width:0px;border-bottom-width:0px;border-left-width:0px;border-style:initial;border-color:initial;font-size:14px;vertical-align:baseline;background-image:initial;background-color:transparent;clear:both;word-wrap:break-word">
I extended the LLVM Kaleidoscope example to support Strings. I added a StringExprAST, which has the virtual Codegen method impl as follows:</p><pre style="margin-top:0px;margin-right:0px;margin-bottom:10px;margin-left:0px;padding-top:5px;padding-right:5px;padding-bottom:5px;padding-left:5px;border-top-width:0px;border-right-width:0px;border-bottom-width:0px;border-left-width:0px;border-style:initial;border-color:initial;font-size:14px;vertical-align:baseline;background-image:initial;background-color:rgb(238,238,238);font-family:Consolas,Menlo,Monaco,'Lucida Console','Liberation Mono','DejaVu Sans Mono','Bitstream Vera Sans Mono','Courier New',monospace,serif;width:auto;max-height:600px">
<code style="margin-top:0px;margin-right:0px;margin-bottom:0px;margin-left:0px;padding-top:0px;padding-right:0px;padding-bottom:0px;padding-left:0px;border-top-width:0px;border-right-width:0px;border-bottom-width:0px;border-left-width:0px;border-style:initial;border-color:initial;font-size:14px;vertical-align:baseline;background-image:initial;background-color:rgb(238,238,238);font-family:Consolas,Menlo,Monaco,'Lucida Console','Liberation Mono','DejaVu Sans Mono','Bitstream Vera Sans Mono','Courier New',monospace,serif">Value *StringExprAST::Codegen() {
  StringRef r(Val);
  return ConstantDataArray::getString(getGlobalContext(), r, false);
}
</code></pre><p style="margin-top:0px;margin-right:0px;margin-bottom:1em;margin-left:0px;padding-top:0px;padding-right:0px;padding-bottom:0px;padding-left:0px;border-top-width:0px;border-right-width:0px;border-bottom-width:0px;border-left-width:0px;border-style:initial;border-color:initial;font-size:14px;vertical-align:baseline;background-image:initial;background-color:transparent;clear:both;word-wrap:break-word">
I am trying to concatenate Strings and have a ConcatExprAST with its Codegen method. Upon trying to access the data in the ConstantDataArray, I need to cast the Value* back to a ConstantDataArray* in order to use the getAsString() method.</p>
<p style="margin-top:0px;margin-right:0px;margin-bottom:1em;margin-left:0px;padding-top:0px;padding-right:0px;padding-bottom:0px;padding-left:0px;border-top-width:0px;border-right-width:0px;border-bottom-width:0px;border-left-width:0px;border-style:initial;border-color:initial;font-size:14px;vertical-align:baseline;background-image:initial;background-color:transparent;clear:both;word-wrap:break-word">
I tried:</p><p style="margin-top:0px;margin-right:0px;margin-bottom:1em;margin-left:0px;padding-top:0px;padding-right:0px;padding-bottom:0px;padding-left:0px;border-top-width:0px;border-right-width:0px;border-bottom-width:0px;border-left-width:0px;border-style:initial;border-color:initial;font-size:14px;vertical-align:baseline;background-image:initial;background-color:transparent;clear:both;word-wrap:break-word">
ConstantDataArray * cda = cast<ConstantDataArray>(v);</p><p style="margin-top:0px;margin-right:0px;margin-bottom:1em;margin-left:0px;padding-top:0px;padding-right:0px;padding-bottom:0px;padding-left:0px;border-top-width:0px;border-right-width:0px;border-bottom-width:0px;border-left-width:0px;border-style:initial;border-color:initial;font-size:14px;vertical-align:baseline;background-image:initial;background-color:transparent;clear:both;word-wrap:break-word">
where v is a Value*.  It does not work.</p><p style="margin-top:0px;margin-right:0px;margin-bottom:1em;margin-left:0px;padding-top:0px;padding-right:0px;padding-bottom:0px;padding-left:0px;border-top-width:0px;border-right-width:0px;border-bottom-width:0px;border-left-width:0px;border-style:initial;border-color:initial;font-size:14px;vertical-align:baseline;background-image:initial;background-color:transparent;clear:both;word-wrap:break-word">
How can I do this?</p><p style="margin-top:0px;margin-right:0px;margin-bottom:1em;margin-left:0px;padding-top:0px;padding-right:0px;padding-bottom:0px;padding-left:0px;border-top-width:0px;border-right-width:0px;border-bottom-width:0px;border-left-width:0px;border-style:initial;border-color:initial;font-size:14px;vertical-align:baseline;background-image:initial;background-color:transparent;clear:both;word-wrap:break-word">
Thanks for any help.</p></span></div>