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-rw-r--r--lib/Transforms/Scalar/MarkModRef.cpp69
1 files changed, 0 insertions, 69 deletions
diff --git a/lib/Transforms/Scalar/MarkModRef.cpp b/lib/Transforms/Scalar/MarkModRef.cpp
deleted file mode 100644
index 5e83ee9310..0000000000
--- a/lib/Transforms/Scalar/MarkModRef.cpp
+++ /dev/null
@@ -1,69 +0,0 @@
-//===--------- MarkModRef.cpp - Mark functions readnone/readonly ----------===//
-//
-// The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// This pass marks functions readnone/readonly based on the results of alias
-// analysis. This requires a sufficiently powerful alias analysis, such as
-// GlobalsModRef (invoke as "opt ... -globalsmodref-aa -markmodref ...").
-//
-//===----------------------------------------------------------------------===//
-
-#define DEBUG_TYPE "markmodref"
-#include "llvm/ADT/Statistic.h"
-#include "llvm/Analysis/AliasAnalysis.h"
-#include "llvm/Support/Compiler.h"
-#include "llvm/Transforms/Scalar.h"
-#include "llvm/Function.h"
-#include "llvm/Pass.h"
-using namespace llvm;
-
-STATISTIC(NumReadNone, "Number of functions marked readnone");
-STATISTIC(NumReadOnly, "Number of functions marked readonly");
-
-namespace {
- struct VISIBILITY_HIDDEN MarkModRef : public FunctionPass {
- static char ID; // Pass identification, replacement for typeid
- MarkModRef() : FunctionPass(&ID) {}
-
- bool runOnFunction(Function &F);
-
- virtual void getAnalysisUsage(AnalysisUsage &AU) const {
- AU.setPreservesCFG();
- AU.addRequired<AliasAnalysis>();
- AU.addPreserved<AliasAnalysis>();
- }
- };
-}
-
-char MarkModRef::ID = 0;
-static RegisterPass<MarkModRef>
-X("markmodref", "Mark functions readnone/readonly");
-
-bool MarkModRef::runOnFunction(Function &F) {
- // FIXME: Wrong for functions with weak linkage.
- if (F.doesNotAccessMemory())
- // Cannot do better.
- return false;
-
- AliasAnalysis &AA = getAnalysis<AliasAnalysis>();
- AliasAnalysis::ModRefBehavior ModRef = AA.getModRefBehavior(&F);
- if (ModRef == AliasAnalysis::DoesNotAccessMemory) {
- F.setDoesNotAccessMemory();
- NumReadNone++;
- return true;
- } else if (ModRef == AliasAnalysis::OnlyReadsMemory && !F.onlyReadsMemory()) {
- F.setOnlyReadsMemory();
- NumReadOnly++;
- return true;
- }
- return false;
-}
-
-FunctionPass *llvm::createMarkModRefPass() {
- return new MarkModRef();
-}