Vendor import of llvm release_32 branch r168974 (effectively, 3.2 RC2):

http://llvm.org/svn/llvm-project/llvm/branches/release_32@168974

1 files changed, 1149 insertions, 0 deletions

diff --git a/lib/Transforms/Utils/SimplifyLibCalls.cpp b/lib/Transforms/Utils/SimplifyLibCalls.cpp
new file mode 100644
index 0000000..c3ea638
--- /dev/null
+++ b/lib/Transforms/Utils/SimplifyLibCalls.cpp
@@ -0,0 +1,1149 @@
+//===------ SimplifyLibCalls.cpp - Library calls simplifier ---------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This is a utility pass used for testing the InstructionSimplify analysis.
+// The analysis is applied to every instruction, and if it simplifies then the
+// instruction is replaced by the simplification.  If you are looking for a pass
+// that performs serious instruction folding, use the instcombine pass instead.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Transforms/Utils/SimplifyLibCalls.h"
+#include "llvm/DataLayout.h"
+#include "llvm/ADT/StringMap.h"
+#include "llvm/Analysis/ValueTracking.h"
+#include "llvm/Function.h"
+#include "llvm/IRBuilder.h"
+#include "llvm/LLVMContext.h"
+#include "llvm/Target/TargetLibraryInfo.h"
+#include "llvm/Transforms/Utils/BuildLibCalls.h"
+
+using namespace llvm;
+
+/// This class is the abstract base class for the set of optimizations that
+/// corresponds to one library call.
+namespace {
+class LibCallOptimization {
+protected:
+  Function *Caller;
+  const DataLayout *TD;
+  const TargetLibraryInfo *TLI;
+  const LibCallSimplifier *LCS;
+  LLVMContext* Context;
+public:
+  LibCallOptimization() { }
+  virtual ~LibCallOptimization() {}
+
+  /// callOptimizer - This pure virtual method is implemented by base classes to
+  /// do various optimizations.  If this returns null then no transformation was
+  /// performed.  If it returns CI, then it transformed the call and CI is to be
+  /// deleted.  If it returns something else, replace CI with the new value and
+  /// delete CI.
+  virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B)
+    =0;
+
+  Value *optimizeCall(CallInst *CI, const DataLayout *TD,
+                      const TargetLibraryInfo *TLI,
+                      const LibCallSimplifier *LCS, IRBuilder<> &B) {
+    Caller = CI->getParent()->getParent();
+    this->TD = TD;
+    this->TLI = TLI;
+    this->LCS = LCS;
+    if (CI->getCalledFunction())
+      Context = &CI->getCalledFunction()->getContext();
+
+    // We never change the calling convention.
+    if (CI->getCallingConv() != llvm::CallingConv::C)
+      return NULL;
+
+    return callOptimizer(CI->getCalledFunction(), CI, B);
+  }
+};
+
+//===----------------------------------------------------------------------===//
+// Helper Functions
+//===----------------------------------------------------------------------===//
+
+/// isOnlyUsedInZeroEqualityComparison - Return true if it only matters that the
+/// value is equal or not-equal to zero.
+static bool isOnlyUsedInZeroEqualityComparison(Value *V) {
+  for (Value::use_iterator UI = V->use_begin(), E = V->use_end();
+       UI != E; ++UI) {
+    if (ICmpInst *IC = dyn_cast<ICmpInst>(*UI))
+      if (IC->isEquality())
+        if (Constant *C = dyn_cast<Constant>(IC->getOperand(1)))
+          if (C->isNullValue())
+            continue;
+    // Unknown instruction.
+    return false;
+  }
+  return true;
+}
+
+/// isOnlyUsedInEqualityComparison - Return true if it is only used in equality
+/// comparisons with With.
+static bool isOnlyUsedInEqualityComparison(Value *V, Value *With) {
+  for (Value::use_iterator UI = V->use_begin(), E = V->use_end();
+       UI != E; ++UI) {
+    if (ICmpInst *IC = dyn_cast<ICmpInst>(*UI))
+      if (IC->isEquality() && IC->getOperand(1) == With)
+        continue;
+    // Unknown instruction.
+    return false;
+  }
+  return true;
+}
+
+//===----------------------------------------------------------------------===//
+// Fortified Library Call Optimizations
+//===----------------------------------------------------------------------===//
+
+struct FortifiedLibCallOptimization : public LibCallOptimization {
+protected:
+  virtual bool isFoldable(unsigned SizeCIOp, unsigned SizeArgOp,
+			  bool isString) const = 0;
+};
+
+struct InstFortifiedLibCallOptimization : public FortifiedLibCallOptimization {
+  CallInst *CI;
+
+  bool isFoldable(unsigned SizeCIOp, unsigned SizeArgOp, bool isString) const {
+    if (CI->getArgOperand(SizeCIOp) == CI->getArgOperand(SizeArgOp))
+      return true;
+    if (ConstantInt *SizeCI =
+                           dyn_cast<ConstantInt>(CI->getArgOperand(SizeCIOp))) {
+      if (SizeCI->isAllOnesValue())
+        return true;
+      if (isString) {
+        uint64_t Len = GetStringLength(CI->getArgOperand(SizeArgOp));
+        // If the length is 0 we don't know how long it is and so we can't
+        // remove the check.
+        if (Len == 0) return false;
+        return SizeCI->getZExtValue() >= Len;
+      }
+      if (ConstantInt *Arg = dyn_cast<ConstantInt>(
+                                                  CI->getArgOperand(SizeArgOp)))
+        return SizeCI->getZExtValue() >= Arg->getZExtValue();
+    }
+    return false;
+  }
+};
+
+struct MemCpyChkOpt : public InstFortifiedLibCallOptimization {
+  virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+    this->CI = CI;
+    FunctionType *FT = Callee->getFunctionType();
+    LLVMContext &Context = CI->getParent()->getContext();
+
+    // Check if this has the right signature.
+    if (FT->getNumParams() != 4 || FT->getReturnType() != FT->getParamType(0) ||
+        !FT->getParamType(0)->isPointerTy() ||
+        !FT->getParamType(1)->isPointerTy() ||
+        FT->getParamType(2) != TD->getIntPtrType(Context) ||
+        FT->getParamType(3) != TD->getIntPtrType(Context))
+      return 0;
+
+    if (isFoldable(3, 2, false)) {
+      B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(1),
+                     CI->getArgOperand(2), 1);
+      return CI->getArgOperand(0);
+    }
+    return 0;
+  }
+};
+
+struct MemMoveChkOpt : public InstFortifiedLibCallOptimization {
+  virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+    this->CI = CI;
+    FunctionType *FT = Callee->getFunctionType();
+    LLVMContext &Context = CI->getParent()->getContext();
+
+    // Check if this has the right signature.
+    if (FT->getNumParams() != 4 || FT->getReturnType() != FT->getParamType(0) ||
+        !FT->getParamType(0)->isPointerTy() ||
+        !FT->getParamType(1)->isPointerTy() ||
+        FT->getParamType(2) != TD->getIntPtrType(Context) ||
+        FT->getParamType(3) != TD->getIntPtrType(Context))
+      return 0;
+
+    if (isFoldable(3, 2, false)) {
+      B.CreateMemMove(CI->getArgOperand(0), CI->getArgOperand(1),
+                      CI->getArgOperand(2), 1);
+      return CI->getArgOperand(0);
+    }
+    return 0;
+  }
+};
+
+struct MemSetChkOpt : public InstFortifiedLibCallOptimization {
+  virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+    this->CI = CI;
+    FunctionType *FT = Callee->getFunctionType();
+    LLVMContext &Context = CI->getParent()->getContext();
+
+    // Check if this has the right signature.
+    if (FT->getNumParams() != 4 || FT->getReturnType() != FT->getParamType(0) ||
+        !FT->getParamType(0)->isPointerTy() ||
+        !FT->getParamType(1)->isIntegerTy() ||
+        FT->getParamType(2) != TD->getIntPtrType(Context) ||
+        FT->getParamType(3) != TD->getIntPtrType(Context))
+      return 0;
+
+    if (isFoldable(3, 2, false)) {
+      Value *Val = B.CreateIntCast(CI->getArgOperand(1), B.getInt8Ty(),
+                                   false);
+      B.CreateMemSet(CI->getArgOperand(0), Val, CI->getArgOperand(2), 1);
+      return CI->getArgOperand(0);
+    }
+    return 0;
+  }
+};
+
+struct StrCpyChkOpt : public InstFortifiedLibCallOptimization {
+  virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+    this->CI = CI;
+    StringRef Name = Callee->getName();
+    FunctionType *FT = Callee->getFunctionType();
+    LLVMContext &Context = CI->getParent()->getContext();
+
+    // Check if this has the right signature.
+    if (FT->getNumParams() != 3 ||
+        FT->getReturnType() != FT->getParamType(0) ||
+        FT->getParamType(0) != FT->getParamType(1) ||
+        FT->getParamType(0) != Type::getInt8PtrTy(Context) ||
+        FT->getParamType(2) != TD->getIntPtrType(Context))
+      return 0;
+
+    Value *Dst = CI->getArgOperand(0), *Src = CI->getArgOperand(1);
+    if (Dst == Src)      // __strcpy_chk(x,x)  -> x
+      return Src;
+
+    // If a) we don't have any length information, or b) we know this will
+    // fit then just lower to a plain strcpy. Otherwise we'll keep our
+    // strcpy_chk call which may fail at runtime if the size is too long.
+    // TODO: It might be nice to get a maximum length out of the possible
+    // string lengths for varying.
+    if (isFoldable(2, 1, true)) {
+      Value *Ret = EmitStrCpy(Dst, Src, B, TD, TLI, Name.substr(2, 6));
+      return Ret;
+    } else {
+      // Maybe we can stil fold __strcpy_chk to __memcpy_chk.
+      uint64_t Len = GetStringLength(Src);
+      if (Len == 0) return 0;
+
+      // This optimization require DataLayout.
+      if (!TD) return 0;
+
+      Value *Ret =
+	EmitMemCpyChk(Dst, Src,
+                      ConstantInt::get(TD->getIntPtrType(Context), Len),
+                      CI->getArgOperand(2), B, TD, TLI);
+      return Ret;
+    }
+    return 0;
+  }
+};
+
+struct StpCpyChkOpt : public InstFortifiedLibCallOptimization {
+  virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+    this->CI = CI;
+    StringRef Name = Callee->getName();
+    FunctionType *FT = Callee->getFunctionType();
+    LLVMContext &Context = CI->getParent()->getContext();
+
+    // Check if this has the right signature.
+    if (FT->getNumParams() != 3 ||
+        FT->getReturnType() != FT->getParamType(0) ||
+        FT->getParamType(0) != FT->getParamType(1) ||
+        FT->getParamType(0) != Type::getInt8PtrTy(Context) ||
+        FT->getParamType(2) != TD->getIntPtrType(FT->getParamType(0)))
+      return 0;
+
+    Value *Dst = CI->getArgOperand(0), *Src = CI->getArgOperand(1);
+    if (Dst == Src) {  // stpcpy(x,x)  -> x+strlen(x)
+      Value *StrLen = EmitStrLen(Src, B, TD, TLI);
+      return StrLen ? B.CreateInBoundsGEP(Dst, StrLen) : 0;
+    }
+
+    // If a) we don't have any length information, or b) we know this will
+    // fit then just lower to a plain stpcpy. Otherwise we'll keep our
+    // stpcpy_chk call which may fail at runtime if the size is too long.
+    // TODO: It might be nice to get a maximum length out of the possible
+    // string lengths for varying.
+    if (isFoldable(2, 1, true)) {
+      Value *Ret = EmitStrCpy(Dst, Src, B, TD, TLI, Name.substr(2, 6));
+      return Ret;
+    } else {
+      // Maybe we can stil fold __stpcpy_chk to __memcpy_chk.
+      uint64_t Len = GetStringLength(Src);
+      if (Len == 0) return 0;
+
+      // This optimization require DataLayout.
+      if (!TD) return 0;
+
+      Type *PT = FT->getParamType(0);
+      Value *LenV = ConstantInt::get(TD->getIntPtrType(PT), Len);
+      Value *DstEnd = B.CreateGEP(Dst,
+                                  ConstantInt::get(TD->getIntPtrType(PT),
+                                                   Len - 1));
+      if (!EmitMemCpyChk(Dst, Src, LenV, CI->getArgOperand(2), B, TD, TLI))
+        return 0;
+      return DstEnd;
+    }
+    return 0;
+  }
+};
+
+struct StrNCpyChkOpt : public InstFortifiedLibCallOptimization {
+  virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+    this->CI = CI;
+    StringRef Name = Callee->getName();
+    FunctionType *FT = Callee->getFunctionType();
+    LLVMContext &Context = CI->getParent()->getContext();
+
+    // Check if this has the right signature.
+    if (FT->getNumParams() != 4 || FT->getReturnType() != FT->getParamType(0) ||
+        FT->getParamType(0) != FT->getParamType(1) ||
+        FT->getParamType(0) != Type::getInt8PtrTy(Context) ||
+        !FT->getParamType(2)->isIntegerTy() ||
+        FT->getParamType(3) != TD->getIntPtrType(Context))
+      return 0;
+
+    if (isFoldable(3, 2, false)) {
+      Value *Ret = EmitStrNCpy(CI->getArgOperand(0), CI->getArgOperand(1),
+                               CI->getArgOperand(2), B, TD, TLI,
+                               Name.substr(2, 7));
+      return Ret;
+    }
+    return 0;
+  }
+};
+
+//===----------------------------------------------------------------------===//
+// String and Memory Library Call Optimizations
+//===----------------------------------------------------------------------===//
+
+struct StrCatOpt : public LibCallOptimization {
+  virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+    // Verify the "strcat" function prototype.
+    FunctionType *FT = Callee->getFunctionType();
+    if (FT->getNumParams() != 2 ||
+        FT->getReturnType() != B.getInt8PtrTy() ||
+        FT->getParamType(0) != FT->getReturnType() ||
+        FT->getParamType(1) != FT->getReturnType())
+      return 0;
+
+    // Extract some information from the instruction
+    Value *Dst = CI->getArgOperand(0);
+    Value *Src = CI->getArgOperand(1);
+
+    // See if we can get the length of the input string.
+    uint64_t Len = GetStringLength(Src);
+    if (Len == 0) return 0;
+    --Len;  // Unbias length.
+
+    // Handle the simple, do-nothing case: strcat(x, "") -> x
+    if (Len == 0)
+      return Dst;
+
+    // These optimizations require DataLayout.
+    if (!TD) return 0;
+
+    return emitStrLenMemCpy(Src, Dst, Len, B);
+  }
+
+  Value *emitStrLenMemCpy(Value *Src, Value *Dst, uint64_t Len,
+                          IRBuilder<> &B) {
+    // We need to find the end of the destination string.  That's where the
+    // memory is to be moved to. We just generate a call to strlen.
+    Value *DstLen = EmitStrLen(Dst, B, TD, TLI);
+    if (!DstLen)
+      return 0;
+
+    // Now that we have the destination's length, we must index into the
+    // destination's pointer to get the actual memcpy destination (end of
+    // the string .. we're concatenating).
+    Value *CpyDst = B.CreateGEP(Dst, DstLen, "endptr");
+
+    // We have enough information to now generate the memcpy call to do the
+    // concatenation for us.  Make a memcpy to copy the nul byte with align = 1.
+    B.CreateMemCpy(CpyDst, Src,
+                   ConstantInt::get(TD->getIntPtrType(*Context), Len + 1), 1);
+    return Dst;
+  }
+};
+
+struct StrNCatOpt : public StrCatOpt {
+  virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+    // Verify the "strncat" function prototype.
+    FunctionType *FT = Callee->getFunctionType();
+    if (FT->getNumParams() != 3 ||
+        FT->getReturnType() != B.getInt8PtrTy() ||
+        FT->getParamType(0) != FT->getReturnType() ||
+        FT->getParamType(1) != FT->getReturnType() ||
+        !FT->getParamType(2)->isIntegerTy())
+      return 0;
+
+    // Extract some information from the instruction
+    Value *Dst = CI->getArgOperand(0);
+    Value *Src = CI->getArgOperand(1);
+    uint64_t Len;
+
+    // We don't do anything if length is not constant
+    if (ConstantInt *LengthArg = dyn_cast<ConstantInt>(CI->getArgOperand(2)))
+      Len = LengthArg->getZExtValue();
+    else
+      return 0;
+
+    // See if we can get the length of the input string.
+    uint64_t SrcLen = GetStringLength(Src);
+    if (SrcLen == 0) return 0;
+    --SrcLen;  // Unbias length.
+
+    // Handle the simple, do-nothing cases:
+    // strncat(x, "", c) -> x
+    // strncat(x,  c, 0) -> x
+    if (SrcLen == 0 || Len == 0) return Dst;
+
+    // These optimizations require DataLayout.
+    if (!TD) return 0;
+
+    // We don't optimize this case
+    if (Len < SrcLen) return 0;
+
+    // strncat(x, s, c) -> strcat(x, s)
+    // s is constant so the strcat can be optimized further
+    return emitStrLenMemCpy(Src, Dst, SrcLen, B);
+  }
+};
+
+struct StrChrOpt : public LibCallOptimization {
+  virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+    // Verify the "strchr" function prototype.
+    FunctionType *FT = Callee->getFunctionType();
+    if (FT->getNumParams() != 2 ||
+        FT->getReturnType() != B.getInt8PtrTy() ||
+        FT->getParamType(0) != FT->getReturnType() ||
+        !FT->getParamType(1)->isIntegerTy(32))
+      return 0;
+
+    Value *SrcStr = CI->getArgOperand(0);
+
+    // If the second operand is non-constant, see if we can compute the length
+    // of the input string and turn this into memchr.
+    ConstantInt *CharC = dyn_cast<ConstantInt>(CI->getArgOperand(1));
+    if (CharC == 0) {
+      // These optimizations require DataLayout.
+      if (!TD) return 0;
+
+      uint64_t Len = GetStringLength(SrcStr);
+      if (Len == 0 || !FT->getParamType(1)->isIntegerTy(32))// memchr needs i32.
+        return 0;
+
+      return EmitMemChr(SrcStr, CI->getArgOperand(1), // include nul.
+                        ConstantInt::get(TD->getIntPtrType(*Context), Len),
+                        B, TD, TLI);
+    }
+
+    // Otherwise, the character is a constant, see if the first argument is
+    // a string literal.  If so, we can constant fold.
+    StringRef Str;
+    if (!getConstantStringInfo(SrcStr, Str))
+      return 0;
+
+    // Compute the offset, make sure to handle the case when we're searching for
+    // zero (a weird way to spell strlen).
+    size_t I = CharC->getSExtValue() == 0 ?
+        Str.size() : Str.find(CharC->getSExtValue());
+    if (I == StringRef::npos) // Didn't find the char.  strchr returns null.
+      return Constant::getNullValue(CI->getType());
+
+    // strchr(s+n,c)  -> gep(s+n+i,c)
+    return B.CreateGEP(SrcStr, B.getInt64(I), "strchr");
+  }
+};
+
+struct StrRChrOpt : public LibCallOptimization {
+  virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+    // Verify the "strrchr" function prototype.
+    FunctionType *FT = Callee->getFunctionType();
+    if (FT->getNumParams() != 2 ||
+        FT->getReturnType() != B.getInt8PtrTy() ||
+        FT->getParamType(0) != FT->getReturnType() ||
+        !FT->getParamType(1)->isIntegerTy(32))
+      return 0;
+
+    Value *SrcStr = CI->getArgOperand(0);
+    ConstantInt *CharC = dyn_cast<ConstantInt>(CI->getArgOperand(1));
+
+    // Cannot fold anything if we're not looking for a constant.
+    if (!CharC)
+      return 0;
+
+    StringRef Str;
+    if (!getConstantStringInfo(SrcStr, Str)) {
+      // strrchr(s, 0) -> strchr(s, 0)
+      if (TD && CharC->isZero())
+        return EmitStrChr(SrcStr, '\0', B, TD, TLI);
+      return 0;
+    }
+
+    // Compute the offset.
+    size_t I = CharC->getSExtValue() == 0 ?
+        Str.size() : Str.rfind(CharC->getSExtValue());
+    if (I == StringRef::npos) // Didn't find the char. Return null.
+      return Constant::getNullValue(CI->getType());
+
+    // strrchr(s+n,c) -> gep(s+n+i,c)
+    return B.CreateGEP(SrcStr, B.getInt64(I), "strrchr");
+  }
+};
+
+struct StrCmpOpt : public LibCallOptimization {
+  virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+    // Verify the "strcmp" function prototype.
+    FunctionType *FT = Callee->getFunctionType();
+    if (FT->getNumParams() != 2 ||
+        !FT->getReturnType()->isIntegerTy(32) ||
+        FT->getParamType(0) != FT->getParamType(1) ||
+        FT->getParamType(0) != B.getInt8PtrTy())
+      return 0;
+
+    Value *Str1P = CI->getArgOperand(0), *Str2P = CI->getArgOperand(1);
+    if (Str1P == Str2P)      // strcmp(x,x)  -> 0
+      return ConstantInt::get(CI->getType(), 0);
+
+    StringRef Str1, Str2;
+    bool HasStr1 = getConstantStringInfo(Str1P, Str1);
+    bool HasStr2 = getConstantStringInfo(Str2P, Str2);
+
+    // strcmp(x, y)  -> cnst  (if both x and y are constant strings)
+    if (HasStr1 && HasStr2)
+      return ConstantInt::get(CI->getType(), Str1.compare(Str2));
+
+    if (HasStr1 && Str1.empty()) // strcmp("", x) -> -*x
+      return B.CreateNeg(B.CreateZExt(B.CreateLoad(Str2P, "strcmpload"),
+                                      CI->getType()));
+
+    if (HasStr2 && Str2.empty()) // strcmp(x,"") -> *x
+      return B.CreateZExt(B.CreateLoad(Str1P, "strcmpload"), CI->getType());
+
+    // strcmp(P, "x") -> memcmp(P, "x", 2)
+    uint64_t Len1 = GetStringLength(Str1P);
+    uint64_t Len2 = GetStringLength(Str2P);
+    if (Len1 && Len2) {
+      // These optimizations require DataLayout.
+      if (!TD) return 0;
+
+      return EmitMemCmp(Str1P, Str2P,
+                        ConstantInt::get(TD->getIntPtrType(*Context),
+                        std::min(Len1, Len2)), B, TD, TLI);
+    }
+
+    return 0;
+  }
+};
+
+struct StrNCmpOpt : public LibCallOptimization {
+  virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+    // Verify the "strncmp" function prototype.
+    FunctionType *FT = Callee->getFunctionType();
+    if (FT->getNumParams() != 3 ||
+        !FT->getReturnType()->isIntegerTy(32) ||
+        FT->getParamType(0) != FT->getParamType(1) ||
+        FT->getParamType(0) != B.getInt8PtrTy() ||
+        !FT->getParamType(2)->isIntegerTy())
+      return 0;
+
+    Value *Str1P = CI->getArgOperand(0), *Str2P = CI->getArgOperand(1);
+    if (Str1P == Str2P)      // strncmp(x,x,n)  -> 0
+      return ConstantInt::get(CI->getType(), 0);
+
+    // Get the length argument if it is constant.
+    uint64_t Length;
+    if (ConstantInt *LengthArg = dyn_cast<ConstantInt>(CI->getArgOperand(2)))
+      Length = LengthArg->getZExtValue();
+    else
+      return 0;
+
+    if (Length == 0) // strncmp(x,y,0)   -> 0
+      return ConstantInt::get(CI->getType(), 0);
+
+    if (TD && Length == 1) // strncmp(x,y,1) -> memcmp(x,y,1)
+      return EmitMemCmp(Str1P, Str2P, CI->getArgOperand(2), B, TD, TLI);
+
+    StringRef Str1, Str2;
+    bool HasStr1 = getConstantStringInfo(Str1P, Str1);
+    bool HasStr2 = getConstantStringInfo(Str2P, Str2);
+
+    // strncmp(x, y)  -> cnst  (if both x and y are constant strings)
+    if (HasStr1 && HasStr2) {
+      StringRef SubStr1 = Str1.substr(0, Length);
+      StringRef SubStr2 = Str2.substr(0, Length);
+      return ConstantInt::get(CI->getType(), SubStr1.compare(SubStr2));
+    }
+
+    if (HasStr1 && Str1.empty())  // strncmp("", x, n) -> -*x
+      return B.CreateNeg(B.CreateZExt(B.CreateLoad(Str2P, "strcmpload"),
+                                      CI->getType()));
+
+    if (HasStr2 && Str2.empty())  // strncmp(x, "", n) -> *x
+      return B.CreateZExt(B.CreateLoad(Str1P, "strcmpload"), CI->getType());
+
+    return 0;
+  }
+};
+
+struct StrCpyOpt : public LibCallOptimization {
+  virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+    // Verify the "strcpy" function prototype.
+    FunctionType *FT = Callee->getFunctionType();
+    if (FT->getNumParams() != 2 ||
+        FT->getReturnType() != FT->getParamType(0) ||
+        FT->getParamType(0) != FT->getParamType(1) ||
+        FT->getParamType(0) != B.getInt8PtrTy())
+      return 0;
+
+    Value *Dst = CI->getArgOperand(0), *Src = CI->getArgOperand(1);
+    if (Dst == Src)      // strcpy(x,x)  -> x
+      return Src;
+
+    // These optimizations require DataLayout.
+    if (!TD) return 0;
+
+    // See if we can get the length of the input string.
+    uint64_t Len = GetStringLength(Src);
+    if (Len == 0) return 0;
+
+    // We have enough information to now generate the memcpy call to do the
+    // copy for us.  Make a memcpy to copy the nul byte with align = 1.
+    B.CreateMemCpy(Dst, Src,
+		   ConstantInt::get(TD->getIntPtrType(*Context), Len), 1);
+    return Dst;
+  }
+};
+
+struct StpCpyOpt: public LibCallOptimization {
+  virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+    // Verify the "stpcpy" function prototype.
+    FunctionType *FT = Callee->getFunctionType();
+    if (FT->getNumParams() != 2 ||
+        FT->getReturnType() != FT->getParamType(0) ||
+        FT->getParamType(0) != FT->getParamType(1) ||
+        FT->getParamType(0) != B.getInt8PtrTy())
+      return 0;
+
+    // These optimizations require DataLayout.
+    if (!TD) return 0;
+
+    Value *Dst = CI->getArgOperand(0), *Src = CI->getArgOperand(1);
+    if (Dst == Src) {  // stpcpy(x,x)  -> x+strlen(x)
+      Value *StrLen = EmitStrLen(Src, B, TD, TLI);
+      return StrLen ? B.CreateInBoundsGEP(Dst, StrLen) : 0;
+    }
+
+    // See if we can get the length of the input string.
+    uint64_t Len = GetStringLength(Src);
+    if (Len == 0) return 0;
+
+    Type *PT = FT->getParamType(0);
+    Value *LenV = ConstantInt::get(TD->getIntPtrType(PT), Len);
+    Value *DstEnd = B.CreateGEP(Dst,
+                                ConstantInt::get(TD->getIntPtrType(PT),
+                                                 Len - 1));
+
+    // We have enough information to now generate the memcpy call to do the
+    // copy for us.  Make a memcpy to copy the nul byte with align = 1.
+    B.CreateMemCpy(Dst, Src, LenV, 1);
+    return DstEnd;
+  }
+};
+
+struct StrNCpyOpt : public LibCallOptimization {
+  virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+    FunctionType *FT = Callee->getFunctionType();
+    if (FT->getNumParams() != 3 || FT->getReturnType() != FT->getParamType(0) ||
+        FT->getParamType(0) != FT->getParamType(1) ||
+        FT->getParamType(0) != B.getInt8PtrTy() ||
+        !FT->getParamType(2)->isIntegerTy())
+      return 0;
+
+    Value *Dst = CI->getArgOperand(0);
+    Value *Src = CI->getArgOperand(1);
+    Value *LenOp = CI->getArgOperand(2);
+
+    // See if we can get the length of the input string.
+    uint64_t SrcLen = GetStringLength(Src);
+    if (SrcLen == 0) return 0;
+    --SrcLen;
+
+    if (SrcLen == 0) {
+      // strncpy(x, "", y) -> memset(x, '\0', y, 1)
+      B.CreateMemSet(Dst, B.getInt8('\0'), LenOp, 1);
+      return Dst;
+    }
+
+    uint64_t Len;
+    if (ConstantInt *LengthArg = dyn_cast<ConstantInt>(LenOp))
+      Len = LengthArg->getZExtValue();
+    else
+      return 0;
+
+    if (Len == 0) return Dst; // strncpy(x, y, 0) -> x
+
+    // These optimizations require DataLayout.
+    if (!TD) return 0;
+
+    // Let strncpy handle the zero padding
+    if (Len > SrcLen+1) return 0;
+
+    Type *PT = FT->getParamType(0);
+    // strncpy(x, s, c) -> memcpy(x, s, c, 1) [s and c are constant]
+    B.CreateMemCpy(Dst, Src,
+                   ConstantInt::get(TD->getIntPtrType(PT), Len), 1);
+
+    return Dst;
+  }
+};
+
+struct StrLenOpt : public LibCallOptimization {
+  virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+    FunctionType *FT = Callee->getFunctionType();
+    if (FT->getNumParams() != 1 ||
+        FT->getParamType(0) != B.getInt8PtrTy() ||
+        !FT->getReturnType()->isIntegerTy())
+      return 0;
+
+    Value *Src = CI->getArgOperand(0);
+
+    // Constant folding: strlen("xyz") -> 3
+    if (uint64_t Len = GetStringLength(Src))
+      return ConstantInt::get(CI->getType(), Len-1);
+
+    // strlen(x) != 0 --> *x != 0
+    // strlen(x) == 0 --> *x == 0
+    if (isOnlyUsedInZeroEqualityComparison(CI))
+      return B.CreateZExt(B.CreateLoad(Src, "strlenfirst"), CI->getType());
+    return 0;
+  }
+};
+
+struct StrPBrkOpt : public LibCallOptimization {
+  virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+    FunctionType *FT = Callee->getFunctionType();
+    if (FT->getNumParams() != 2 ||
+        FT->getParamType(0) != B.getInt8PtrTy() ||
+        FT->getParamType(1) != FT->getParamType(0) ||
+        FT->getReturnType() != FT->getParamType(0))
+      return 0;
+
+    StringRef S1, S2;
+    bool HasS1 = getConstantStringInfo(CI->getArgOperand(0), S1);
+    bool HasS2 = getConstantStringInfo(CI->getArgOperand(1), S2);
+
+    // strpbrk(s, "") -> NULL
+    // strpbrk("", s) -> NULL
+    if ((HasS1 && S1.empty()) || (HasS2 && S2.empty()))
+      return Constant::getNullValue(CI->getType());
+
+    // Constant folding.
+    if (HasS1 && HasS2) {
+      size_t I = S1.find_first_of(S2);
+      if (I == std::string::npos) // No match.
+        return Constant::getNullValue(CI->getType());
+
+      return B.CreateGEP(CI->getArgOperand(0), B.getInt64(I), "strpbrk");
+    }
+
+    // strpbrk(s, "a") -> strchr(s, 'a')
+    if (TD && HasS2 && S2.size() == 1)
+      return EmitStrChr(CI->getArgOperand(0), S2[0], B, TD, TLI);
+
+    return 0;
+  }
+};
+
+struct StrToOpt : public LibCallOptimization {
+  virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+    FunctionType *FT = Callee->getFunctionType();
+    if ((FT->getNumParams() != 2 && FT->getNumParams() != 3) ||
+        !FT->getParamType(0)->isPointerTy() ||
+        !FT->getParamType(1)->isPointerTy())
+      return 0;
+
+    Value *EndPtr = CI->getArgOperand(1);
+    if (isa<ConstantPointerNull>(EndPtr)) {
+      // With a null EndPtr, this function won't capture the main argument.
+      // It would be readonly too, except that it still may write to errno.
+      CI->addAttribute(1, Attributes::get(Callee->getContext(),
+                                          Attributes::NoCapture));
+    }
+
+    return 0;
+  }
+};
+
+struct StrSpnOpt : public LibCallOptimization {
+  virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+    FunctionType *FT = Callee->getFunctionType();
+    if (FT->getNumParams() != 2 ||
+        FT->getParamType(0) != B.getInt8PtrTy() ||
+        FT->getParamType(1) != FT->getParamType(0) ||
+        !FT->getReturnType()->isIntegerTy())
+      return 0;
+
+    StringRef S1, S2;
+    bool HasS1 = getConstantStringInfo(CI->getArgOperand(0), S1);
+    bool HasS2 = getConstantStringInfo(CI->getArgOperand(1), S2);
+
+    // strspn(s, "") -> 0
+    // strspn("", s) -> 0
+    if ((HasS1 && S1.empty()) || (HasS2 && S2.empty()))
+      return Constant::getNullValue(CI->getType());
+
+    // Constant folding.
+    if (HasS1 && HasS2) {
+      size_t Pos = S1.find_first_not_of(S2);
+      if (Pos == StringRef::npos) Pos = S1.size();
+      return ConstantInt::get(CI->getType(), Pos);
+    }
+
+    return 0;
+  }
+};
+
+struct StrCSpnOpt : public LibCallOptimization {
+  virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+    FunctionType *FT = Callee->getFunctionType();
+    if (FT->getNumParams() != 2 ||
+        FT->getParamType(0) != B.getInt8PtrTy() ||
+        FT->getParamType(1) != FT->getParamType(0) ||
+        !FT->getReturnType()->isIntegerTy())
+      return 0;
+
+    StringRef S1, S2;
+    bool HasS1 = getConstantStringInfo(CI->getArgOperand(0), S1);
+    bool HasS2 = getConstantStringInfo(CI->getArgOperand(1), S2);
+
+    // strcspn("", s) -> 0
+    if (HasS1 && S1.empty())
+      return Constant::getNullValue(CI->getType());
+
+    // Constant folding.
+    if (HasS1 && HasS2) {
+      size_t Pos = S1.find_first_of(S2);
+      if (Pos == StringRef::npos) Pos = S1.size();
+      return ConstantInt::get(CI->getType(), Pos);
+    }
+
+    // strcspn(s, "") -> strlen(s)
+    if (TD && HasS2 && S2.empty())
+      return EmitStrLen(CI->getArgOperand(0), B, TD, TLI);
+
+    return 0;
+  }
+};
+
+struct StrStrOpt : public LibCallOptimization {
+  virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+    FunctionType *FT = Callee->getFunctionType();
+    if (FT->getNumParams() != 2 ||
+        !FT->getParamType(0)->isPointerTy() ||
+        !FT->getParamType(1)->isPointerTy() ||
+        !FT->getReturnType()->isPointerTy())
+      return 0;
+
+    // fold strstr(x, x) -> x.
+    if (CI->getArgOperand(0) == CI->getArgOperand(1))
+      return B.CreateBitCast(CI->getArgOperand(0), CI->getType());
+
+    // fold strstr(a, b) == a -> strncmp(a, b, strlen(b)) == 0
+    if (TD && isOnlyUsedInEqualityComparison(CI, CI->getArgOperand(0))) {
+      Value *StrLen = EmitStrLen(CI->getArgOperand(1), B, TD, TLI);
+      if (!StrLen)
+        return 0;
+      Value *StrNCmp = EmitStrNCmp(CI->getArgOperand(0), CI->getArgOperand(1),
+                                   StrLen, B, TD, TLI);
+      if (!StrNCmp)
+        return 0;
+      for (Value::use_iterator UI = CI->use_begin(), UE = CI->use_end();
+           UI != UE; ) {
+        ICmpInst *Old = cast<ICmpInst>(*UI++);
+        Value *Cmp = B.CreateICmp(Old->getPredicate(), StrNCmp,
+                                  ConstantInt::getNullValue(StrNCmp->getType()),
+                                  "cmp");
+        LCS->replaceAllUsesWith(Old, Cmp);
+      }
+      return CI;
+    }
+
+    // See if either input string is a constant string.
+    StringRef SearchStr, ToFindStr;
+    bool HasStr1 = getConstantStringInfo(CI->getArgOperand(0), SearchStr);
+    bool HasStr2 = getConstantStringInfo(CI->getArgOperand(1), ToFindStr);
+
+    // fold strstr(x, "") -> x.
+    if (HasStr2 && ToFindStr.empty())
+      return B.CreateBitCast(CI->getArgOperand(0), CI->getType());
+
+    // If both strings are known, constant fold it.
+    if (HasStr1 && HasStr2) {
+      std::string::size_type Offset = SearchStr.find(ToFindStr);
+
+      if (Offset == StringRef::npos) // strstr("foo", "bar") -> null
+        return Constant::getNullValue(CI->getType());
+
+      // strstr("abcd", "bc") -> gep((char*)"abcd", 1)
+      Value *Result = CastToCStr(CI->getArgOperand(0), B);
+      Result = B.CreateConstInBoundsGEP1_64(Result, Offset, "strstr");
+      return B.CreateBitCast(Result, CI->getType());
+    }
+
+    // fold strstr(x, "y") -> strchr(x, 'y').
+    if (HasStr2 && ToFindStr.size() == 1) {
+      Value *StrChr= EmitStrChr(CI->getArgOperand(0), ToFindStr[0], B, TD, TLI);
+      return StrChr ? B.CreateBitCast(StrChr, CI->getType()) : 0;
+    }
+    return 0;
+  }
+};
+
+struct MemCmpOpt : public LibCallOptimization {
+  virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+    FunctionType *FT = Callee->getFunctionType();
+    if (FT->getNumParams() != 3 || !FT->getParamType(0)->isPointerTy() ||
+        !FT->getParamType(1)->isPointerTy() ||
+        !FT->getReturnType()->isIntegerTy(32))
+      return 0;
+
+    Value *LHS = CI->getArgOperand(0), *RHS = CI->getArgOperand(1);
+
+    if (LHS == RHS)  // memcmp(s,s,x) -> 0
+      return Constant::getNullValue(CI->getType());
+
+    // Make sure we have a constant length.
+    ConstantInt *LenC = dyn_cast<ConstantInt>(CI->getArgOperand(2));
+    if (!LenC) return 0;
+    uint64_t Len = LenC->getZExtValue();
+
+    if (Len == 0) // memcmp(s1,s2,0) -> 0
+      return Constant::getNullValue(CI->getType());
+
+    // memcmp(S1,S2,1) -> *(unsigned char*)LHS - *(unsigned char*)RHS
+    if (Len == 1) {
+      Value *LHSV = B.CreateZExt(B.CreateLoad(CastToCStr(LHS, B), "lhsc"),
+                                 CI->getType(), "lhsv");
+      Value *RHSV = B.CreateZExt(B.CreateLoad(CastToCStr(RHS, B), "rhsc"),
+                                 CI->getType(), "rhsv");
+      return B.CreateSub(LHSV, RHSV, "chardiff");
+    }
+
+    // Constant folding: memcmp(x, y, l) -> cnst (all arguments are constant)
+    StringRef LHSStr, RHSStr;
+    if (getConstantStringInfo(LHS, LHSStr) &&
+        getConstantStringInfo(RHS, RHSStr)) {
+      // Make sure we're not reading out-of-bounds memory.
+      if (Len > LHSStr.size() || Len > RHSStr.size())
+        return 0;
+      uint64_t Ret = memcmp(LHSStr.data(), RHSStr.data(), Len);
+      return ConstantInt::get(CI->getType(), Ret);
+    }
+
+    return 0;
+  }
+};
+
+struct MemCpyOpt : public LibCallOptimization {
+  virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+    // These optimizations require DataLayout.
+    if (!TD) return 0;
+
+    FunctionType *FT = Callee->getFunctionType();
+    if (FT->getNumParams() != 3 || FT->getReturnType() != FT->getParamType(0) ||
+        !FT->getParamType(0)->isPointerTy() ||
+        !FT->getParamType(1)->isPointerTy() ||
+        FT->getParamType(2) != TD->getIntPtrType(*Context))
+      return 0;
+
+    // memcpy(x, y, n) -> llvm.memcpy(x, y, n, 1)
+    B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(1),
+                   CI->getArgOperand(2), 1);
+    return CI->getArgOperand(0);
+  }
+};
+
+struct MemMoveOpt : public LibCallOptimization {
+  virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+    // These optimizations require DataLayout.
+    if (!TD) return 0;
+
+    FunctionType *FT = Callee->getFunctionType();
+    if (FT->getNumParams() != 3 || FT->getReturnType() != FT->getParamType(0) ||
+        !FT->getParamType(0)->isPointerTy() ||
+        !FT->getParamType(1)->isPointerTy() ||
+        FT->getParamType(2) != TD->getIntPtrType(*Context))
+      return 0;
+
+    // memmove(x, y, n) -> llvm.memmove(x, y, n, 1)
+    B.CreateMemMove(CI->getArgOperand(0), CI->getArgOperand(1),
+                    CI->getArgOperand(2), 1);
+    return CI->getArgOperand(0);
+  }
+};
+
+struct MemSetOpt : public LibCallOptimization {
+  virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+    // These optimizations require DataLayout.
+    if (!TD) return 0;
+
+    FunctionType *FT = Callee->getFunctionType();
+    if (FT->getNumParams() != 3 || FT->getReturnType() != FT->getParamType(0) ||
+        !FT->getParamType(0)->isPointerTy() ||
+        !FT->getParamType(1)->isIntegerTy() ||
+        FT->getParamType(2) != TD->getIntPtrType(*Context))
+      return 0;
+
+    // memset(p, v, n) -> llvm.memset(p, v, n, 1)
+    Value *Val = B.CreateIntCast(CI->getArgOperand(1), B.getInt8Ty(), false);
+    B.CreateMemSet(CI->getArgOperand(0), Val, CI->getArgOperand(2), 1);
+    return CI->getArgOperand(0);
+  }
+};
+
+} // End anonymous namespace.
+
+namespace llvm {
+
+class LibCallSimplifierImpl {
+  const DataLayout *TD;
+  const TargetLibraryInfo *TLI;
+  const LibCallSimplifier *LCS;
+  StringMap<LibCallOptimization*> Optimizations;
+
+  // Fortified library call optimizations.
+  MemCpyChkOpt MemCpyChk;
+  MemMoveChkOpt MemMoveChk;
+  MemSetChkOpt MemSetChk;
+  StrCpyChkOpt StrCpyChk;
+  StpCpyChkOpt StpCpyChk;
+  StrNCpyChkOpt StrNCpyChk;
+
+  // String library call optimizations.
+  StrCatOpt StrCat;
+  StrNCatOpt StrNCat;
+  StrChrOpt StrChr;
+  StrRChrOpt StrRChr;
+  StrCmpOpt StrCmp;
+  StrNCmpOpt StrNCmp;
+  StrCpyOpt StrCpy;
+  StpCpyOpt StpCpy;
+  StrNCpyOpt StrNCpy;
+  StrLenOpt StrLen;
+  StrPBrkOpt StrPBrk;
+  StrToOpt StrTo;
+  StrSpnOpt StrSpn;
+  StrCSpnOpt StrCSpn;
+  StrStrOpt StrStr;
+
+  // Memory library call optimizations.
+  MemCmpOpt MemCmp;
+  MemCpyOpt MemCpy;
+  MemMoveOpt MemMove;
+  MemSetOpt MemSet;
+
+  void initOptimizations();
+  void addOpt(LibFunc::Func F, LibCallOptimization* Opt);
+public:
+  LibCallSimplifierImpl(const DataLayout *TD, const TargetLibraryInfo *TLI,
+                        const LibCallSimplifier *LCS) {
+    this->TD = TD;
+    this->TLI = TLI;
+    this->LCS = LCS;
+  }
+
+  Value *optimizeCall(CallInst *CI);
+};
+
+void LibCallSimplifierImpl::initOptimizations() {
+  // Fortified library call optimizations.
+  Optimizations["__memcpy_chk"] = &MemCpyChk;
+  Optimizations["__memmove_chk"] = &MemMoveChk;
+  Optimizations["__memset_chk"] = &MemSetChk;
+  Optimizations["__strcpy_chk"] = &StrCpyChk;
+  Optimizations["__stpcpy_chk"] = &StpCpyChk;
+  Optimizations["__strncpy_chk"] = &StrNCpyChk;
+  Optimizations["__stpncpy_chk"] = &StrNCpyChk;
+
+  // String library call optimizations.
+  addOpt(LibFunc::strcat, &StrCat);
+  addOpt(LibFunc::strncat, &StrNCat);
+  addOpt(LibFunc::strchr, &StrChr);
+  addOpt(LibFunc::strrchr, &StrRChr);
+  addOpt(LibFunc::strcmp, &StrCmp);
+  addOpt(LibFunc::strncmp, &StrNCmp);
+  addOpt(LibFunc::strcpy, &StrCpy);
+  addOpt(LibFunc::stpcpy, &StpCpy);
+  addOpt(LibFunc::strncpy, &StrNCpy);
+  addOpt(LibFunc::strlen, &StrLen);
+  addOpt(LibFunc::strpbrk, &StrPBrk);
+  addOpt(LibFunc::strtol, &StrTo);
+  addOpt(LibFunc::strtod, &StrTo);
+  addOpt(LibFunc::strtof, &StrTo);
+  addOpt(LibFunc::strtoul, &StrTo);
+  addOpt(LibFunc::strtoll, &StrTo);
+  addOpt(LibFunc::strtold, &StrTo);
+  addOpt(LibFunc::strtoull, &StrTo);
+  addOpt(LibFunc::strspn, &StrSpn);
+  addOpt(LibFunc::strcspn, &StrCSpn);
+  addOpt(LibFunc::strstr, &StrStr);
+
+  // Memory library call optimizations.
+  addOpt(LibFunc::memcmp, &MemCmp);
+  addOpt(LibFunc::memcpy, &MemCpy);
+  addOpt(LibFunc::memmove, &MemMove);
+  addOpt(LibFunc::memset, &MemSet);
+}
+
+Value *LibCallSimplifierImpl::optimizeCall(CallInst *CI) {
+  if (Optimizations.empty())
+    initOptimizations();
+
+  Function *Callee = CI->getCalledFunction();
+  LibCallOptimization *LCO = Optimizations.lookup(Callee->getName());
+  if (LCO) {
+    IRBuilder<> Builder(CI);
+    return LCO->optimizeCall(CI, TD, TLI, LCS, Builder);
+  }
+  return 0;
+}
+
+void LibCallSimplifierImpl::addOpt(LibFunc::Func F, LibCallOptimization* Opt) {
+  if (TLI->has(F))
+    Optimizations[TLI->getName(F)] = Opt;
+}
+
+LibCallSimplifier::LibCallSimplifier(const DataLayout *TD,
+                                     const TargetLibraryInfo *TLI) {
+  Impl = new LibCallSimplifierImpl(TD, TLI, this);
+}
+
+LibCallSimplifier::~LibCallSimplifier() {
+  delete Impl;
+}
+
+Value *LibCallSimplifier::optimizeCall(CallInst *CI) {
+  return Impl->optimizeCall(CI);
+}
+
+void LibCallSimplifier::replaceAllUsesWith(Instruction *I, Value *With) const {
+  I->replaceAllUsesWith(With);
+  I->eraseFromParent();
+}
+
+}