[llvm-commits] CVS: llvm/lib/Analysis/IPA/CallGraphSCCPass.cpp

[Chris Lattner]

Changes in directory llvm/lib/Analysis/IPA:

CallGraphSCCPass.cpp added (r1.1)

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Log message:

Initial checkin of the CallGraphSCCPass class


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Diffs of the changes:

Index: llvm/lib/Analysis/IPA/CallGraphSCCPass.cpp
diff -c /dev/null llvm/lib/Analysis/IPA/CallGraphSCCPass.cpp:1.1
*** /dev/null	Sat Aug 30 20:55:07 2003
--- llvm/lib/Analysis/IPA/CallGraphSCCPass.cpp	Sat Aug 30 20:54:57 2003
***************
*** 0 ****
--- 1,30 ----
+ //===- CallGraphSCCPass.cpp - Pass that operates BU on call graph ---------===//
+ //
+ // This file implements the CallGraphSCCPass class, which is used for passes
+ // which are implemented as bottom-up traversals on the call graph.  Because
+ // there may be cycles in the call graph, passes of this type operate on the
+ // call-graph in SCC order: that is, they process function bottom-up, except for
+ // recursive functions, which they process all at once.
+ //
+ //===----------------------------------------------------------------------===//
+ 
+ #include "llvm/CallGraphSCCPass.h"
+ #include "llvm/Analysis/CallGraph.h"
+ #include "Support/TarjanSCCIterator.h"
+ 
+ /// getAnalysisUsage - For this class, we declare that we require and preserve
+ /// the call graph.  If the derived class implements this method, it should
+ /// always explicitly call the implementation here.
+ void CallGraphSCCPass::getAnalysisUsage(AnalysisUsage &AU) const {
+   AU.addRequired<CallGraph>();
+   AU.addPreserved<CallGraph>();
+ }
+ 
+ bool CallGraphSCCPass::run(Module &M) {
+   CallGraph &CG = getAnalysis<CallGraph>();
+   bool Changed = false;
+   for (TarjanSCC_iterator<CallGraph*> I = tarj_begin(&CG), E = tarj_end(&CG);
+        I != E; ++I)
+     Changed = runOnSCC(**I);
+   return Changed;
+ }