Initial checkin of new "Internalize" pass for GCCLD
llvm-svn: 2362
diff --git a/llvm/lib/Transforms/IPO/Internalize.cpp b/llvm/lib/Transforms/IPO/Internalize.cpp
new file mode 100644
index 0000000..aadde7c
--- /dev/null
+++ b/llvm/lib/Transforms/IPO/Internalize.cpp
@@ -0,0 +1,38 @@
+//===-- Internalize.cpp - Mark functions internal -------------------------===//
+//
+// This pass loops over all of the functions in the input module, looking for a
+// main function. If a main function is found, all other functions are marked
+// as internal.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Transforms/IPO/Internalize.h"
+#include "llvm/Pass.h"
+#include "llvm/Module.h"
+#include "llvm/Function.h"
+
+class InternalizePass : public Pass {
+ virtual bool run(Module *M) {
+ bool FoundMain = false; // Look for a function named main...
+ for (Module::iterator I = M->begin(), E = M->end(); I != E; ++I)
+ if ((*I)->getName() == "main") {
+ FoundMain = true;
+ break;
+ }
+
+ if (!FoundMain) return false; // No main found, must be a library...
+
+ bool Changed = false;
+
+ // Found a main function, mark all functions not named main as internal.
+ for (Module::iterator I = M->begin(), E = M->end(); I != E; ++I)
+ if ((*I)->getName() != "main") // Leave the main function external
+ (*I)->setInternalLinkage(Changed = true);
+
+ return Changed;
+ }
+};
+
+Pass *createInternalizePass() {
+ return new InternalizePass();
+}