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-rw-r--r--lib/Transforms/IPO/StripDeadPrototypes.cpp61
1 files changed, 61 insertions, 0 deletions
diff --git a/lib/Transforms/IPO/StripDeadPrototypes.cpp b/lib/Transforms/IPO/StripDeadPrototypes.cpp
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+++ b/lib/Transforms/IPO/StripDeadPrototypes.cpp
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+//===-- StripDeadPrototypes.cpp - Removed unused function declarations ----===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file was developed by Reid Spencer and is distributed under the
+// University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This pass loops over all of the functions in the input module, looking for
+// dead declarations and removes them.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Transforms/IPO.h"
+#include "llvm/Pass.h"
+#include "llvm/Module.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/Support/Debug.h"
+#include <vector>
+using namespace llvm;
+
+STATISTIC(NumDeadPrototypes, "Number of dead prototypes removed");
+
+namespace {
+
+/// @brief Pass to remove unused function declarations.
+class StripDeadPrototypesPass : public ModulePass {
+public:
+ StripDeadPrototypesPass() { }
+ virtual bool runOnModule(Module &M);
+};
+RegisterPass<StripDeadPrototypesPass> X("strip-dead-prototypes",
+ "Strip Unused Function Prototypes");
+
+bool StripDeadPrototypesPass::runOnModule(Module &M) {
+ // Collect all the functions we want to erase
+ std::vector<Function*> FuncsToErase;
+ for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I)
+ if (I->isDeclaration() && // Function must be only a prototype
+ I->use_empty()) { // Function must not be used
+ FuncsToErase.push_back(&(*I));
+ }
+
+ // Erase the functions
+ for (std::vector<Function*>::iterator I = FuncsToErase.begin(),
+ E = FuncsToErase.end(); I != E; ++I )
+ (*I)->eraseFromParent();
+
+ // Increment the statistic
+ NumDeadPrototypes += FuncsToErase.size();
+
+ // Return an indication of whether we changed anything or not.
+ return !FuncsToErase.empty();
+}
+
+} // end anonymous namespace
+
+ModulePass *llvm::createStripDeadPrototypesPass() {
+ return new StripDeadPrototypesPass();
+}