llvm/docs/tutorial/LangImpl4.html

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<title>Kaleidoscope: Adding JIT and Optimizer Support</title>
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<meta name="author" content="Chris Lattner">
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<div class="doc_title">Kaleidoscope: Adding JIT and Optimizer Support</div>
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<p>Written by <a href="mailto:sabre@nondot.org">Chris Lattner</a></p>
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<div class="doc_section"><a name="intro">Part 4 Introduction</a></div>
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<div class="doc_text">
<p>Welcome to part 4 of the "<a href="index.html">Implementing a language with
LLVM</a>" tutorial.</p>
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<div class="doc_section"><a name="basics">Code Generation setup</a></div>
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<p>
In order to generate LLVM IR, we want some simple setup to get started. First,
we define virtual codegen methods in each AST class:</p>
<div class="doc_code">
<pre>
/// ExprAST - Base class for all expression nodes.
class ExprAST {
public:
virtual ~ExprAST() {}
virtual Value *Codegen() = 0;
};
/// NumberExprAST - Expression class for numeric literals like "1.0".
class NumberExprAST : public ExprAST {
double Val;
public:
explicit NumberExprAST(double val) : Val(val) {}
virtual Value *Codegen();
};
...
</pre>
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<a href="mailto:sabre@nondot.org">Chris Lattner</a><br>
<a href="http://llvm.org">The LLVM Compiler Infrastructure</a><br>
Last modified: $Date: 2007-10-17 11:05:13 -0700 (Wed, 17 Oct 2007) $
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