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diff --git a/docs/libIndex.html b/docs/libIndex.html deleted file mode 100644 index e722ee1..0000000 --- a/docs/libIndex.html +++ /dev/null @@ -1,267 +0,0 @@ -<html> -<head> - <title>The Index Library</title> - <link type="text/css" rel="stylesheet" href="../menu.css" /> - <link type="text/css" rel="stylesheet" href="../content.css" /> - <style type="text/css"> - td { - vertical-align: top; - } - </style> -</head> - -<body> - -<!--#include virtual="../menu.html.incl"--> - -<div id="content"> - -<h1>The Index Library</h1> - - <p><b>Table of Contents</b></p> - <ul> - <li><a href="#philosophy">Design Philosophy</a></li> - <li><a href="#classes">Classes</a> - <ul> - <li><a href="#entity">Entity</a></li> - <li><a href="#astlocation">ASTLocation</a></li> - <li><a href="#declreferencemap">DeclReferenceMap</a></li> - </ul> - </li> - <li><a href="#functions">Functions</a> - <ul> - <li><a href="#resolveloc">ResolveLocationInAST</a></li> - </ul> - </li> - <li><a href="#astfiles">AST Files</a></li> - <li><a href="#indextest">index-test tool</a> - <ul> - <li><a href="#indextestusage">Usage</a></li> - <li><a href="#indextestexamples">Examples</a></li> - </ul> - </li> -</ul> - -<h2 id="philosophy">Design Philosophy</h2> - -<p> The Index library is meant to provide the basic infrastructure for - cross-translation-unit analysis and is primarily focused on indexing - related functionality. It provides an API for clients that need to - accurately map the AST nodes of the ASTContext to the locations in the source files. -It also allows them to analyze information across multiple translation units.</p> - -<p>As a "general rule", ASTContexts are considered the primary source of -information that a client wants about a translation unit. There will be no such class as an - "indexing database" that stores, for example, source locations of identifiers separately from ASTContext. -All the information that a client needs from a translation unit will be extracted from the ASTContext.</p> - -<h2 id="classes">Classes</h2> - -<h3 id="entity">Entity</h3> - -<p>To be able to reason about semantically the same Decls that are contained in multiple ASTContexts, the 'Entity' class was introduced. -An Entity is an ASTContext-independent "token" that can be created from a Decl (and a typename in the future) with -the purpose to "resolve" it into a Decl belonging to another ASTContext. Some examples to make the concept of Entities more clear:</p> - -<p> -t1.c: -<pre class="code_example"> -void foo(void); -void bar(void); -</pre> -</p> - -<p> -t2.c: -<pre class="code_example"> -void foo(void) { -} -</pre> -</p> - -<p> -Translation unit <code>t1.c</code> contains 2 Entities <code>foo</code> and <code>bar</code>, while <code>t2.c</code> contains 1 Entity <code>foo</code>. -Entities are uniqued in such a way that the Entity* pointer for <code>t1.c/foo</code> is the same as the Entity* pointer for <code>t2.c/foo</code>. -An Entity doesn't convey any information about the declaration, it is more like an opaque pointer used only to get the -associated Decl out of an ASTContext so that the actual information for the declaration can be accessed. -Another important aspect of Entities is that they can only be created/associated for declarations that are visible outside the -translation unit. This means that for: -</p> -<p> -t3.c: -<pre class="code_example"> -static void foo(void); -</pre> -</p> -<p> -there can be no Entity (if you ask for the Entity* of the static function <code>foo</code> you'll get a null pointer). -This is for 2 reasons: -<ul> -<li>To preserve the invariant that the same Entity* pointers refer to the same semantic Decls. - In the above example <code>t1.c/foo</code> and <code>t2.c/foo</code> are the same, while <code>t3.c/foo</code> is different.</li> -<li>The purpose of Entity is to get the same semantic Decl from multiple ASTContexts. For a Decl that is not visible - outside of its own translation unit, you don't need an Entity since it won't appear in another ASTContext.</li> -</ul> -</p> - -<h3 id="astlocation">ASTLocation</h3> - -Encapsulates a "point" in the AST tree of the ASTContext. -It represents either a Decl*, or a Stmt* along with its immediate Decl* parent. -An example for its usage is that libIndex will provide the references of <code>foo</code> in the form of ASTLocations, -"pointing" at the expressions that reference <code>foo</code>. - -<h3 id="declreferencemap">DeclReferenceMap</h3> - -Accepts an ASTContext and creates a mapping from NamedDecls to the ASTLocations that reference them (in the same ASTContext). - -<h2 id="functions">Functions</h2> - -<h3 id="resolveloc">ResolveLocationInAST</h3> - -A function that accepts an ASTContext and a SourceLocation which it resolves into an ASTLocation. - -<h2 id="astfiles">AST Files</h2> - -The precompiled headers implementation of clang (<a href="http://clang.llvm.org/docs/PCHInternals.html">PCH</a>) is ideal for storing an ASTContext in a compact form that -will be loaded later for AST analysis. An "AST file" refers to a translation unit that was "compiled" into a precompiled header file. - -<h2 id="indextest">index-test tool</h2> - -<h3 id="indextestusage">Usage</h3> - -A command-line tool that exercises the libIndex API, useful for testing its features. -As input it accepts multiple AST files (representing multiple translation units) and a few options: - -<p> -<pre class="code_example"> - -point-at [file:line:column] -</pre> -Resolves a [file:line:column] triplet into a ASTLocation from the first AST file. If no other option is specified, it prints the ASTLocation. -It also prints a declaration's associated doxygen comment, if one is available. -</p> - -<p> -<pre class="code_example"> - -print-refs -</pre> -Prints the ASTLocations that reference the declaration that was resolved out of the [file:line:column] triplet -</p> - -<p> -<pre class="code_example"> - -print-defs -</pre> -Prints the ASTLocations that define the resolved declaration -</p> - -<p> -<pre class="code_example"> - -print-decls -</pre> -Prints the ASTLocations that declare the resolved declaration -</p> - -<h3 id="indextestexamples">Examples</h3> - -<p> -Here's an example of using index-test: -</p> - -<p> -We have 3 files, -</p> - -<p> -foo.h: -<pre class="code_example"> -extern int global_var; - -void foo_func(int param1); -void bar_func(void); -</pre> - -t1.c: -<pre class="code_example"> -#include "foo.h" - -void foo_func(int param1) { - int local_var = global_var; - for (int for_var = 100; for_var < 500; ++for_var) { - local_var = param1 + for_var; - } - bar_func(); -} -</pre> - -t2.c: -<pre class="code_example"> -#include "foo.h" - -int global_var = 10; - -void bar_func(void) { - global_var += 100; - foo_func(global_var); -} -</pre> -</p> - -<p> -You first get AST files out of <code>t1.c</code> and <code>t2.c</code>: - -<pre class="code_example"> -$ clang -emit-ast t1.c -o t1.ast -$ clang -emit-ast t2.c -o t2.ast -</pre> -</p> - -<p> -Find the ASTLocation under this position of <code>t1.c</code>: -<pre class="code_example"> -[...] -void foo_func(int param1) { - int local_var = global_var; - ^ -[...] -</pre> - -<pre class="code_example"> -$ index-test t1.ast -point-at t1.c:4:23 -> [Decl: Var local_var | Stmt: DeclRefExpr global_var] <t1.c:4:19, t1.c:4:19> -</pre> -</p> - -<p> -Find the declaration: - -<pre class="code_example"> -$ index-test t1.ast -point-at t1.c:4:23 -print-decls -> [Decl: Var global_var] <foo.h:1:12, foo.h:1:12> -</pre> -</p> - -<p> -Find the references: - -<pre class="code_example"> -$ index-test t1.ast t2.ast -point-at t1.c:4:23 -print-refs -> [Decl: Var local_var | Stmt: DeclRefExpr global_var] <t1.c:4:19, t1.c:4:19> -> [Decl: Function bar_func | Stmt: DeclRefExpr global_var] <t2.c:6:3, t2.c:6:3> -> [Decl: Function bar_func | Stmt: DeclRefExpr global_var] <t2.c:7:12, t2.c:7:12> -</pre> -</p> - -<p> -Find definitions: - -<pre class="code_example"> -$ index-test t1.ast t2.ast -point-at t1.c:4:23 -print-defs -> [Decl: Var global_var] <t2.c:3:5, t2.c:3:18> -</pre> -</p> - -</div> - -</body> -</html> |