<pre>
<i>// Loop over all of the phi nodes in a basic block</i>
BasicBlock::iterator BBI = BB->begin();
- for (; <a href="#PhiNode">PHINode</a> *PN = dyn_cast<<a href="#PHINode">PHINode</a>>(&*BBI); ++BBI)
+ for (; <a href="#PhiNode">PHINode</a> *PN = dyn_cast<<a href="#PHINode">PHINode</a>>(BBI); ++BBI)
cerr << *PN;
</pre><p>
Using the <tt>DEBUG()</tt> macro instead of a home brewed solution allows you to
now have to create "yet another" command line option for the debug output for
-your pass. Note that <tt>DEBUG()</tt> macros are disabled for optimized
-builds, so they do not cause a performance impact at all.<p>
+your pass. Note that <tt>DEBUG()</tt> macros are disabled for optimized builds,
+so they do not cause a performance impact at all (for the same reason, they
+should also not contain side-effects!).<p>
+
+One additional nice thing about the <tt>DEBUG()</tt> macro is that you can
+enable or disable it directly in gdb. Just use "<tt>set DebugFlag=0</tt>" or
+"<tt>set DebugFlag=1</tt>" from the gdb if the program is running. If the
+program hasn't been started yet, you can always just run it with
+<tt>-debug</tt>.<p>
<!-- ======================================================================= -->
<pre>Instruction* pinst = i;</pre>
-<b>Caveat emptor</b>: The above syntax works <i>only</i> when you're <i>not</i>
-working with <tt>dyn_cast</tt>. The template definition of <tt><a
-href="#isa">dyn_cast</a></tt> isn't implemented to handle this yet, so you'll
-still need the following in order for things to work properly:
-
-<pre>
-BasicBlock::iterator bbi = ...;
-<a href="#BranchInst">BranchInst</a>* b = <a href="#isa">dyn_cast</a><<a href="#BranchInst">BranchInst</a>>(&*bbi);
-</pre>
-
It's also possible to turn a class pointer into the corresponding
iterator. Usually, this conversion is quite inexpensive. The
following code snippet illustrates use of the conversion constructors
AllocaInst* instToReplace = ...;
BasicBlock::iterator ii(instToReplace);
ReplaceInstWithInst(instToReplace->getParent()->getInstList(), ii,
- new AllocaInst(Type::IntTy, 0, "ptrToReplacedInt");
+ new AllocaInst(Type::IntTy, 0, "ptrToReplacedInt"));
</pre>
</ul>
Returns the <a href="#BasicBlock"><tt>BasicBlock</tt></a> that this
<tt>Instruction</tt> is embedded into.<p>
-<li><tt>bool
hasSideEffects()</tt><p>
+<li><tt>bool
mayWriteToMemory()</tt><p>
-Returns true if the instruction has side effects, i.e. it is a <tt>call</tt>,
+Returns true if the instruction writes to memory, i.e. it is a <tt>call</tt>,
<tt>free</tt>, <tt>invoke</tt>, or <tt>store</tt>.<p>
<li><tt>unsigned getOpcode()</tt><p>
and returns the return type of the function, or the <a
href="#FunctionType"><tt>FunctionType</tt></a> of the actual function.<p>
-
-<li><tt>bool hasSymbolTable() const</tt><p>
-
-Return true if the <tt>Function</tt> has a symbol table allocated to it and if
-there is at least one entry in it.<p>
-
<li><tt><a href="#SymbolTable">SymbolTable</a> *getSymbolTable()</tt><p>
Return a pointer to the <a href="#SymbolTable"><tt>SymbolTable</tt></a> for this
-<tt>Function</tt> or a null pointer if one has not been allocated (because there
-are no named values in the function).<p>
-
-<li><tt><a href="#SymbolTable">SymbolTable</a> *getSymbolTableSure()</tt><p>
-
-Return a pointer to the <a href="#SymbolTable"><tt>SymbolTable</tt></a> for this
-<tt>Function</tt> or allocate a new <a
-href="#SymbolTable"><tt>SymbolTable</tt></a> if one is not already around. This
-should only be used when adding elements to the <a
-href="#SymbolTable"><tt>SymbolTable</tt></a>, so that empty symbol tables are
-not left laying around.<p>
+<tt>Function</tt>.<p>
<!-- Symbol table stuff -->
<hr size=0>
-<li><tt>bool hasSymbolTable() const</tt><p>
-
-Return true if the <tt>Module</tt> has a symbol table allocated to it and if
-there is at least one entry in it.<p>
-
<li><tt><a href="#SymbolTable">SymbolTable</a> *getSymbolTable()</tt><p>
-Return a pointer to the <a href="#SymbolTable"><tt>SymbolTable</tt></a> for this
-<tt>Module</tt> or a null pointer if one has not been allocated (because there
-are no named values in the function).<p>
-
-<li><tt><a href="#SymbolTable">SymbolTable</a> *getSymbolTableSure()</tt><p>
-
-Return a pointer to the <a href="#SymbolTable"><tt>SymbolTable</tt></a> for this
-<tt>Module</tt> or allocate a new <a
-href="#SymbolTable"><tt>SymbolTable</tt></a> if one is not already around. This
-should only be used when adding elements to the <a
-href="#SymbolTable"><tt>SymbolTable</tt></a>, so that empty symbol tables are
-not left laying around.<p>
+Return a reference to the <a href="#SymbolTable"><tt>SymbolTable</tt></a> for
+this <tt>Module</tt>.<p>
<!-- Convenience methods -->
<a href="mailto:sabre@nondot.org">Chris Lattner</a></address>
<!-- Created: Tue Aug 6 15:00:33 CDT 2002 -->
<!-- hhmts start -->
-Last modified: Sun Oct 20 21:37:06 CDT 2002
+Last modified: Wed Apr 23 11:21:57 CDT 2003
<!-- hhmts end -->
</font></body></html>
projects / oota-llvm.git / blobdiff