[TLI] Unify LibFunc signature checking. NFCI.

[ab]

Summary

I tried to be as close as possible to the strongest check that existed before; cleaning these up properly is left for future work.

The PointerSize is a little awkward; alternatives welcome. I thought about making TLI require DataLayout as well, but you'd have the same problem of picking a default.

Also, I'm playing with a new tablegen backend for these; what do people think?

[mehdi_amini]

I thought about making TLI require DataLayout as well, but you'd have the same problem of picking a default.

I'm not sure to follow: if you require the DataLayout why would you have a problem with a "default"? You always have the value don't you?

[ab]

In D19469#410333, @joker.eph wrote:

I thought about making TLI require DataLayout as well, but you'd have the same problem of picking a default.

I'm not sure to follow: if you require the DataLayout why would you have a problem with a "default"? You always have the value don't you?

The analysis isn't always built with a module context; the 0-argument constructor would only have the empty DataLayout.

[mehdi_amini]

Well either the Caller of getLibFunc supplies it or there should be some "doInitialization()` like every pass?

[ab]

Well either the Caller of getLibFunc supplies it or there should be some "doInitialization()` like every pass?

How about this: get the DataLayout from the function's parent, if it has one. Otherwise, default to isIntegerTy()?

[mehdi_amini]

There is no *if*. The data layout is not optional on the Module. There is always one.

[mehdi_amini]

Following our discussion offline, LGTM.

include/llvm/Analysis/TargetLibraryInfo.h

class TargetLibraryInfoImpl {
   }
 
   /// Vectorization descriptors - sorted by ScalarFnName.
   std::vector<VecDesc> VectorDescs;
   /// Scalarization descriptors - same content as VectorDescs but sorted based
   /// on VectorFnName rather than ScalarFnName.
   std::vector<VecDesc> ScalarDescs;
 
+  /// The size (in bits) of a pointer in addresspace 0.
+  /// Used to verify the integer width of size_t types, for, e.g., strlen.
+  /// If 0 (unknown), these types only need to be integers: width isn't checked.
+  unsigned PointerSize = 0;
+
+  /// Return true if the function type FTy is valid for the library function
+  /// F, regardless of whether the function is available.
+  bool isValidProtoForLibFunc(const FunctionType &FTy, LibFunc::Func F) const;
+
 public:
   /// List of known vector-functions libraries.
   ///
   /// The vector-functions library defines, which functions are vectorizable
   /// and with which factor. The library can be specified by either frontend,
   /// or a commandline option, and then used by
   /// addVectorizableFunctionsFromVecLib for filling up the tables of
   /// vectorizable functions.
public:
   TargetLibraryInfoImpl &operator=(TargetLibraryInfoImpl &&TLI);
 
   /// Searches for a particular function name.
   ///
   /// If it is one of the known library functions, return true and set F to the
   /// corresponding value.
   bool getLibFunc(StringRef funcName, LibFunc::Func &F) const;
 
+  /// Searches for a particular function name, also checking that its type is
+  /// valid for the library function matching that name.
+  ///
+  /// If it is one of the known library functions, return true and set F to the
+  /// corresponding value.
+  bool getLibFunc(const Function &FDecl, LibFunc::Func &F) const;
+
   /// Forces a function to be marked as unavailable.
   void setUnavailable(LibFunc::Func F) {
     setState(F, Unavailable);
   }
 
   /// Forces a function to be marked as available.
   void setAvailable(LibFunc::Func F) {
     setState(F, StandardName);
public:
   /// Searches for a particular function name.
   ///
   /// If it is one of the known library functions, return true and set F to the
   /// corresponding value.
   bool getLibFunc(StringRef funcName, LibFunc::Func &F) const {
     return Impl->getLibFunc(funcName, F);
   }
 
+  bool getLibFunc(const Function &FDecl, LibFunc::Func &F) const {
+    return Impl->getLibFunc(FDecl, F);
+  }
+
   /// Tests whether a library function is available.
   bool has(LibFunc::Func F) const {
     return Impl->getState(F) != TargetLibraryInfoImpl::Unavailable;
   }
   bool isFunctionVectorizable(StringRef F, unsigned VF) const {
     return Impl->isFunctionVectorizable(F, VF);
   }
   bool isFunctionVectorizable(StringRef F) const {

lib/Analysis/BasicAliasAnalysis.cpp

do {
     return AAResultBase::pointsToConstantMemory(Loc, OrLocal);
 
   } while (!Worklist.empty() && --MaxLookup);
 
   Visited.clear();
   return Worklist.empty();
 }
 
-// FIXME: This code is duplicated with MemoryLocation and should be hoisted to
-// some common utility location.
-static bool isMemsetPattern16(const Function *MS,
-                              const TargetLibraryInfo &TLI) {
-  if (TLI.has(LibFunc::memset_pattern16) &&
-      MS->getName() == "memset_pattern16") {
-    FunctionType *MemsetType = MS->getFunctionType();
-    if (!MemsetType->isVarArg() && MemsetType->getNumParams() == 3 &&
-        isa<PointerType>(MemsetType->getParamType(0)) &&
-        isa<PointerType>(MemsetType->getParamType(1)) &&
-        isa<IntegerType>(MemsetType->getParamType(2)))
-      return true;
-  }
-  return false;
-}
-
 /// Returns the behavior when calling the given call site.
 FunctionModRefBehavior BasicAAResult::getModRefBehavior(ImmutableCallSite CS) {
   if (CS.doesNotAccessMemory())
     // Can't do better than this.
     return FMRB_DoesNotAccessMemory;
 
   FunctionModRefBehavior Min = FMRB_UnknownModRefBehavior;
 
case Intrinsic::memmove:
         return true;
     }
 
   // We can bound the aliasing properties of memset_pattern16 just as we can
   // for memcpy/memset.  This is particularly important because the
   // LoopIdiomRecognizer likes to turn loops into calls to memset_pattern16
   // whenever possible.  Note that all but the missing writeonly attribute are
   // handled via InferFunctionAttr.
-  if (CS.getCalledFunction() && isMemsetPattern16(CS.getCalledFunction(), TLI))
+  LibFunc::Func F;
+  if (CS.getCalledFunction() && TLI.getLibFunc(*CS.getCalledFunction(), F) &&
+      F == LibFunc::memset_pattern16 && TLI.has(F))
     if (ArgIdx == 0)
       return true;
 
   // TODO: memset_pattern4, memset_pattern8
   // TODO: _chk variants
   // TODO: strcmp, strcpy
 
   return false;

lib/Analysis/MemoryLocation.cpp

MemoryLocation MemoryLocation::getForDest(const MemIntrinsic *MTI) {
   // memcpy/memmove can have AA tags. For memcpy, they apply
   // to both the source and the destination.
   AAMDNodes AATags;
   MTI->getAAMetadata(AATags);
 
   return MemoryLocation(MTI->getRawDest(), Size, AATags);
 }
 
-// FIXME: This code is duplicated with BasicAliasAnalysis and should be hoisted
-// to some common utility location.
-static bool isMemsetPattern16(const Function *MS,
-                              const TargetLibraryInfo &TLI) {
-  if (TLI.has(LibFunc::memset_pattern16) &&
-      MS->getName() == "memset_pattern16") {
-    FunctionType *MemsetType = MS->getFunctionType();
-    if (!MemsetType->isVarArg() && MemsetType->getNumParams() == 3 &&
-        isa<PointerType>(MemsetType->getParamType(0)) &&
-        isa<PointerType>(MemsetType->getParamType(1)) &&
-        isa<IntegerType>(MemsetType->getParamType(2)))
-      return true;
-  }
-
-  return false;
-}
-
 MemoryLocation MemoryLocation::getForArgument(ImmutableCallSite CS,
                                               unsigned ArgIdx,
                                               const TargetLibraryInfo &TLI) {
   AAMDNodes AATags;
   CS->getAAMetadata(AATags);
   const Value *Arg = CS.getArgument(ArgIdx);
 
   // We may be able to produce an exact size for known intrinsics.
case Intrinsic::arm_neon_vst1:
           Arg, DL.getTypeStoreSize(II->getArgOperand(1)->getType()), AATags);
     }
   }
 
   // We can bound the aliasing properties of memset_pattern16 just as we can
   // for memcpy/memset.  This is particularly important because the
   // LoopIdiomRecognizer likes to turn loops into calls to memset_pattern16
   // whenever possible.
-  if (CS.getCalledFunction() &&
-      isMemsetPattern16(CS.getCalledFunction(), TLI)) {
+  LibFunc::Func F;
+  if (CS.getCalledFunction() && TLI.getLibFunc(*CS.getCalledFunction(), F) &&
+      F == LibFunc::memset_pattern16 && TLI.has(F)) {
     assert((ArgIdx == 0 || ArgIdx == 1) &&
            "Invalid argument index for memset_pattern16");
     if (ArgIdx == 1)
       return MemoryLocation(Arg, 16, AATags);
     if (const ConstantInt *LenCI = dyn_cast<ConstantInt>(CS.getArgument(2)))
       return MemoryLocation(Arg, LenCI->getZExtValue(), AATags);
   }
   // FIXME: Handle memset_pattern4 and memset_pattern8 also.
 
   return MemoryLocation(CS.getArgument(ArgIdx), UnknownSize, AATags);
 }

lib/Analysis/TargetLibraryInfo.cpp

if (T.isNVPTX()) {
     TLI.setAvailable(LibFunc::nvvm_reflect);
   } else {
     TLI.setUnavailable(LibFunc::nvvm_reflect);
   }
 
   TLI.addVectorizableFunctionsFromVecLib(ClVectorLibrary);
 }
 
+/// Figure out the pointer integer size (for things like size_t) from the arch.
+static unsigned getTriplePointerBitWidth(const Triple &T) {
+  if (T.isArch64Bit())
+    return 64;
+  if (T.isArch32Bit())
+    return 32;
+  if (T.isArch16Bit())
+    return 16;
+  return 0;
+}
+
 TargetLibraryInfoImpl::TargetLibraryInfoImpl() {
   // Default to everything being available.
   memset(AvailableArray, -1, sizeof(AvailableArray));
 
   initialize(*this, Triple(), StandardNames);
 }
 
 TargetLibraryInfoImpl::TargetLibraryInfoImpl(const Triple &T) {
   // Default to everything being available.
   memset(AvailableArray, -1, sizeof(AvailableArray));
 
   initialize(*this, T, StandardNames);
+  PointerSize = getTriplePointerBitWidth(T);
 }
 
 TargetLibraryInfoImpl::TargetLibraryInfoImpl(const TargetLibraryInfoImpl &TLI)
-    : CustomNames(TLI.CustomNames) {
+    : CustomNames(TLI.CustomNames), PointerSize(TLI.PointerSize) {
   memcpy(AvailableArray, TLI.AvailableArray, sizeof(AvailableArray));
   VectorDescs = TLI.VectorDescs;
   ScalarDescs = TLI.ScalarDescs;
 }
 
 TargetLibraryInfoImpl::TargetLibraryInfoImpl(TargetLibraryInfoImpl &&TLI)
-    : CustomNames(std::move(TLI.CustomNames)) {
+    : CustomNames(std::move(TLI.CustomNames)), PointerSize(TLI.PointerSize) {
   std::move(std::begin(TLI.AvailableArray), std::end(TLI.AvailableArray),
             AvailableArray);
   VectorDescs = TLI.VectorDescs;
   ScalarDescs = TLI.ScalarDescs;
 }
 
 TargetLibraryInfoImpl &TargetLibraryInfoImpl::operator=(const TargetLibraryInfoImpl &TLI) {
   CustomNames = TLI.CustomNames;
const char *const *I = std::lower_bound(
       });
   if (I != End && *I == funcName) {
     F = (LibFunc::Func)(I - Start);
     return true;
   }
   return false;
 }
 
+bool TargetLibraryInfoImpl::isValidProtoForLibFunc(const FunctionType &FTy,
+                                                   LibFunc::Func F) const {
+  LLVMContext &Ctx = FTy.getContext();
+  Type *PCharTy = Type::getInt8PtrTy(Ctx);
+  auto IsIntPtrTy = [this](Type *Ty) {
+    return PointerSize ? Ty->isIntegerTy(PointerSize) : Ty->isIntegerTy();
+  };
+  unsigned NumParams = FTy.getNumParams();
+
+  switch (F) {
+  case LibFunc::strlen:
+    return (NumParams == 1 && FTy.getParamType(0)->isPointerTy() &&
+            FTy.getReturnType()->isIntegerTy());
+
+  case LibFunc::strchr:
+  case LibFunc::strrchr:
+    return (NumParams == 2 && FTy.getReturnType()->isPointerTy() &&
+            FTy.getParamType(0) == FTy.getReturnType() &&
+            FTy.getParamType(1)->isIntegerTy());
+
+  case LibFunc::strtol:
+  case LibFunc::strtod:
+  case LibFunc::strtof:
+  case LibFunc::strtoul:
+  case LibFunc::strtoll:
+  case LibFunc::strtold:
+  case LibFunc::strtoull:
+    return ((NumParams == 2 || NumParams == 3) &&
+            FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(1)->isPointerTy());
+  case LibFunc::strcat:
+    return (NumParams == 2 && FTy.getReturnType()->isPointerTy() &&
+            FTy.getParamType(0) == FTy.getReturnType() &&
+            FTy.getParamType(1) == FTy.getReturnType());
+
+  case LibFunc::strncat:
+    return (NumParams == 3 && FTy.getReturnType()->isPointerTy() &&
+            FTy.getParamType(0) == FTy.getReturnType() &&
+            FTy.getParamType(1) == FTy.getReturnType() &&
+            FTy.getParamType(2)->isIntegerTy());
+
+  case LibFunc::strcpy_chk:
+  case LibFunc::stpcpy_chk:
+    --NumParams;
+    if (!IsIntPtrTy(FTy.getParamType(NumParams)))
+      return false;
+  // fallthrough
+  case LibFunc::strcpy:
+  case LibFunc::stpcpy:
+    return (NumParams == 2 && FTy.getReturnType() == FTy.getParamType(0) &&
+            FTy.getParamType(0) == FTy.getParamType(1) &&
+            FTy.getParamType(0) == PCharTy);
+
+  case LibFunc::strncpy_chk:
+  case LibFunc::stpncpy_chk:
+    --NumParams;
+    if (!IsIntPtrTy(FTy.getParamType(NumParams)))
+      return false;
+  // fallthrough
+  case LibFunc::strncpy:
+  case LibFunc::stpncpy:
+    return (NumParams == 3 && FTy.getReturnType() == FTy.getParamType(0) &&
+            FTy.getParamType(0) == FTy.getParamType(1) &&
+            FTy.getParamType(0) == PCharTy &&
+            FTy.getParamType(2)->isIntegerTy());
+
+  case LibFunc::strxfrm:
+    return (NumParams == 3 && FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(1)->isPointerTy());
+
+  case LibFunc::strcmp:
+    return (NumParams == 2 && FTy.getReturnType()->isIntegerTy(32) &&
+            FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(0) == FTy.getParamType(1));
+
+  case LibFunc::strncmp:
+    return (NumParams == 3 && FTy.getReturnType()->isIntegerTy(32) &&
+            FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(0) == FTy.getParamType(1) &&
+            FTy.getParamType(2)->isIntegerTy());
+
+  case LibFunc::strspn:
+  case LibFunc::strcspn:
+    return (NumParams == 2 && FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(0) == FTy.getParamType(1) &&
+            FTy.getReturnType()->isIntegerTy());
+
+  case LibFunc::strcoll:
+  case LibFunc::strcasecmp:
+  case LibFunc::strncasecmp:
+    return (NumParams >= 2 && FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(1)->isPointerTy());
+
+  case LibFunc::strstr:
+    return (NumParams == 2 && FTy.getReturnType()->isPointerTy() &&
+            FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(1)->isPointerTy());
+
+  case LibFunc::strpbrk:
+    return (NumParams == 2 && FTy.getParamType(0)->isPointerTy() &&
+            FTy.getReturnType() == FTy.getParamType(0) &&
+            FTy.getParamType(0) == FTy.getParamType(1));
+
+  case LibFunc::strtok:
+  case LibFunc::strtok_r:
+    return (NumParams >= 2 && FTy.getParamType(1)->isPointerTy());
+  case LibFunc::scanf:
+    return (NumParams >= 1 && FTy.getParamType(0)->isPointerTy());
+  case LibFunc::setbuf:
+  case LibFunc::setvbuf:
+    return (NumParams >= 1 && FTy.getParamType(0)->isPointerTy());
+  case LibFunc::strdup:
+  case LibFunc::strndup:
+    return (NumParams >= 1 && FTy.getReturnType()->isPointerTy() &&
+            FTy.getParamType(0)->isPointerTy());
+  case LibFunc::stat:
+  case LibFunc::statvfs:
+    return (NumParams >= 2 && FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(1)->isPointerTy());
+  case LibFunc::sscanf:
+    return (NumParams >= 2 && FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(1)->isPointerTy());
+  case LibFunc::sprintf:
+    return (NumParams >= 2 && FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(1)->isPointerTy());
+  case LibFunc::snprintf:
+    return (NumParams == 3 && FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(2)->isPointerTy());
+  case LibFunc::setitimer:
+    return (NumParams == 3 && FTy.getParamType(1)->isPointerTy() &&
+            FTy.getParamType(2)->isPointerTy());
+  case LibFunc::system:
+    return (NumParams == 1 && FTy.getParamType(0)->isPointerTy());
+  case LibFunc::malloc:
+    return (NumParams == 1 && FTy.getReturnType()->isPointerTy());
+  case LibFunc::memcmp:
+    return (NumParams == 3 && FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(1)->isPointerTy() &&
+            FTy.getReturnType()->isIntegerTy(32));
+
+  case LibFunc::memchr:
+  case LibFunc::memrchr:
+    return (NumParams == 3 && FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(1)->isIntegerTy(32) &&
+            FTy.getParamType(2)->isIntegerTy() &&
+            FTy.getReturnType()->isPointerTy());
+  case LibFunc::modf:
+  case LibFunc::modff:
+  case LibFunc::modfl:
+    return (NumParams >= 2 && FTy.getParamType(1)->isPointerTy());
+
+  case LibFunc::memcpy_chk:
+  case LibFunc::memmove_chk:
+    --NumParams;
+    if (!IsIntPtrTy(FTy.getParamType(NumParams)))
+      return false;
+  // fallthrough
+  case LibFunc::memcpy:
+  case LibFunc::memmove:
+    return (NumParams == 3 && FTy.getReturnType() == FTy.getParamType(0) &&
+            FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(1)->isPointerTy() &&
+            IsIntPtrTy(FTy.getParamType(2)));
+
+  case LibFunc::memset_chk:
+    --NumParams;
+    if (!IsIntPtrTy(FTy.getParamType(NumParams)))
+      return false;
+  // fallthrough
+  case LibFunc::memset:
+    return (NumParams == 3 && FTy.getReturnType() == FTy.getParamType(0) &&
+            FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(1)->isIntegerTy() &&
+            IsIntPtrTy(FTy.getParamType(2)));
+
+  case LibFunc::memccpy:
+    return (NumParams >= 2 && FTy.getParamType(1)->isPointerTy());
+  case LibFunc::memalign:
+    return (FTy.getReturnType()->isPointerTy());
+  case LibFunc::mkdir:
+    return (NumParams == 0 && FTy.getParamType(0)->isPointerTy());
+  case LibFunc::mktime:
+    return (NumParams == 0 && FTy.getParamType(0)->isPointerTy());
+  case LibFunc::realloc:
+    return (NumParams == 2 && FTy.getParamType(0)->isPointerTy() &&
+            FTy.getReturnType()->isPointerTy());
+  case LibFunc::read:
+    return (NumParams == 3 && FTy.getParamType(1)->isPointerTy());
+  case LibFunc::rewind:
+    return (NumParams >= 1 && FTy.getParamType(0)->isPointerTy());
+  case LibFunc::rmdir:
+  case LibFunc::remove:
+  case LibFunc::realpath:
+    return (NumParams >= 1 && FTy.getParamType(0)->isPointerTy());
+  case LibFunc::rename:
+    return (NumParams >= 2 && FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(1)->isPointerTy());
+  case LibFunc::readlink:
+    return (NumParams >= 2 && FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(1)->isPointerTy());
+  case LibFunc::write:
+    return (NumParams == 3 && FTy.getParamType(1)->isPointerTy());
+  case LibFunc::bcopy:
+    return (NumParams == 3 && FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(1)->isPointerTy());
+  case LibFunc::bcmp:
+    return (NumParams == 3 && FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(1)->isPointerTy());
+  case LibFunc::bzero:
+    return (NumParams == 2 && FTy.getParamType(0)->isPointerTy());
+  case LibFunc::calloc:
+    return (NumParams == 2 && FTy.getReturnType()->isPointerTy());
+  case LibFunc::chmod:
+  case LibFunc::chown:
+    return (NumParams == 0 && FTy.getParamType(0)->isPointerTy());
+  case LibFunc::ctermid:
+  case LibFunc::clearerr:
+  case LibFunc::closedir:
+    return (NumParams == 0 && FTy.getParamType(0)->isPointerTy());
+  case LibFunc::atoi:
+  case LibFunc::atol:
+  case LibFunc::atof:
+  case LibFunc::atoll:
+    return (NumParams == 1 && FTy.getParamType(0)->isPointerTy());
+  case LibFunc::access:
+    return (NumParams == 2 && FTy.getParamType(0)->isPointerTy());
+  case LibFunc::fopen:
+    return (NumParams == 2 && FTy.getReturnType()->isPointerTy() &&
+            FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(1)->isPointerTy());
+  case LibFunc::fdopen:
+    return (NumParams == 2 && FTy.getReturnType()->isPointerTy() &&
+            FTy.getParamType(1)->isPointerTy());
+  case LibFunc::feof:
+  case LibFunc::free:
+  case LibFunc::fseek:
+  case LibFunc::ftell:
+  case LibFunc::fgetc:
+  case LibFunc::fseeko:
+  case LibFunc::ftello:
+  case LibFunc::fileno:
+  case LibFunc::fflush:
+  case LibFunc::fclose:
+  case LibFunc::fsetpos:
+  case LibFunc::flockfile:
+  case LibFunc::funlockfile:
+  case LibFunc::ftrylockfile:
+    return (NumParams == 0 && FTy.getParamType(0)->isPointerTy());
+  case LibFunc::ferror:
+    return (NumParams == 1 && FTy.getParamType(0)->isPointerTy());
+  case LibFunc::fputc:
+  case LibFunc::fstat:
+  case LibFunc::frexp:
+  case LibFunc::frexpf:
+  case LibFunc::frexpl:
+  case LibFunc::fstatvfs:
+    return (NumParams == 2 && FTy.getParamType(1)->isPointerTy());
+  case LibFunc::fgets:
+    return (NumParams == 3 && FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(2)->isPointerTy());
+  case LibFunc::fread:
+    return (NumParams == 4 && FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(3)->isPointerTy());
+  case LibFunc::fwrite:
+    return (NumParams == 4 && FTy.getReturnType()->isIntegerTy() &&
+            FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(1)->isIntegerTy() &&
+            FTy.getParamType(2)->isIntegerTy() &&
+            FTy.getParamType(3)->isPointerTy());
+  case LibFunc::fputs:
+    return (NumParams >= 2 && FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(1)->isPointerTy());
+  case LibFunc::fscanf:
+  case LibFunc::fprintf:
+    return (NumParams >= 2 && FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(1)->isPointerTy());
+  case LibFunc::fgetpos:
+    return (NumParams >= 2 && FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(1)->isPointerTy());
+  case LibFunc::getc:
+  case LibFunc::getlogin_r:
+  case LibFunc::getc_unlocked:
+    return (NumParams == 0 && FTy.getParamType(0)->isPointerTy());
+  case LibFunc::getenv:
+    return (NumParams == 1 && FTy.getParamType(0)->isPointerTy());
+  case LibFunc::gets:
+  case LibFunc::getchar:
+  case LibFunc::getitimer:
+    return (NumParams == 2 && FTy.getParamType(1)->isPointerTy());
+  case LibFunc::getpwnam:
+    return (NumParams == 1 && FTy.getParamType(0)->isPointerTy());
+  case LibFunc::ungetc:
+    return (NumParams == 2 && FTy.getParamType(1)->isPointerTy());
+  case LibFunc::uname:
+    return (NumParams == 1 && FTy.getParamType(0)->isPointerTy());
+  case LibFunc::unlink:
+    return (NumParams == 1 && FTy.getParamType(0)->isPointerTy());
+  case LibFunc::unsetenv:
+    return (NumParams == 1 && FTy.getParamType(0)->isPointerTy());
+  case LibFunc::utime:
+  case LibFunc::utimes:
+    return (NumParams == 2 && FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(1)->isPointerTy());
+  case LibFunc::putc:
+    return (NumParams == 2 && FTy.getParamType(1)->isPointerTy());
+  case LibFunc::puts:
+  case LibFunc::printf:
+  case LibFunc::perror:
+    return (NumParams == 1 && FTy.getParamType(0)->isPointerTy());
+  case LibFunc::pread:
+  case LibFunc::pwrite:
+    return (NumParams == 4 && FTy.getParamType(1)->isPointerTy());
+  case LibFunc::putchar:
+  case LibFunc::popen:
+    return (NumParams == 2 && FTy.getReturnType()->isPointerTy() &&
+            FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(1)->isPointerTy());
+  case LibFunc::pclose:
+    return (NumParams == 1 && FTy.getParamType(0)->isPointerTy());
+  case LibFunc::vscanf:
+    return (NumParams == 2 && FTy.getParamType(1)->isPointerTy());
+  case LibFunc::vsscanf:
+    return (NumParams == 3 && FTy.getParamType(1)->isPointerTy() &&
+            FTy.getParamType(2)->isPointerTy());
+  case LibFunc::vfscanf:
+    return (NumParams == 3 && FTy.getParamType(1)->isPointerTy() &&
+            FTy.getParamType(2)->isPointerTy());
+  case LibFunc::valloc:
+    return (FTy.getReturnType()->isPointerTy());
+  case LibFunc::vprintf:
+    return (NumParams == 2 && FTy.getParamType(0)->isPointerTy());
+  case LibFunc::vfprintf:
+  case LibFunc::vsprintf:
+    return (NumParams == 3 && FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(1)->isPointerTy());
+  case LibFunc::vsnprintf:
+    return (NumParams == 4 && FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(2)->isPointerTy());
+  case LibFunc::open:
+    return (NumParams >= 2 && FTy.getParamType(0)->isPointerTy());
+  case LibFunc::opendir:
+    return (NumParams == 1 && FTy.getReturnType()->isPointerTy() &&
+            FTy.getParamType(0)->isPointerTy());
+  case LibFunc::tmpfile:
+    return (FTy.getReturnType()->isPointerTy());
+  case LibFunc::times:
+    return (NumParams == 1 && FTy.getParamType(0)->isPointerTy());
+  case LibFunc::htonl:
+  case LibFunc::htons:
+  case LibFunc::ntohl:
+  case LibFunc::ntohs:
+  case LibFunc::lstat:
+    return (NumParams == 2 && FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(1)->isPointerTy());
+  case LibFunc::lchown:
+    return (NumParams == 3 && FTy.getParamType(0)->isPointerTy());
+  case LibFunc::qsort:
+    return (NumParams == 4 && FTy.getParamType(3)->isPointerTy());
+  case LibFunc::dunder_strdup:
+  case LibFunc::dunder_strndup:
+    return (NumParams >= 1 && FTy.getReturnType()->isPointerTy() &&
+            FTy.getParamType(0)->isPointerTy());
+  case LibFunc::dunder_strtok_r:
+    return (NumParams == 3 && FTy.getParamType(1)->isPointerTy());
+  case LibFunc::under_IO_getc:
+    return (NumParams == 1 && FTy.getParamType(0)->isPointerTy());
+  case LibFunc::under_IO_putc:
+    return (NumParams == 2 && FTy.getParamType(1)->isPointerTy());
+  case LibFunc::dunder_isoc99_scanf:
+    return (NumParams >= 1 && FTy.getParamType(0)->isPointerTy());
+  case LibFunc::stat64:
+  case LibFunc::lstat64:
+  case LibFunc::statvfs64:
+    return (NumParams >= 1 && FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(1)->isPointerTy());
+  case LibFunc::dunder_isoc99_sscanf:
+    return (NumParams >= 1 && FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(1)->isPointerTy());
+  case LibFunc::fopen64:
+    return (NumParams == 2 && FTy.getReturnType()->isPointerTy() &&
+            FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(1)->isPointerTy());
+  case LibFunc::fseeko64:
+  case LibFunc::ftello64:
+    return (NumParams == 0 && FTy.getParamType(0)->isPointerTy());
+  case LibFunc::tmpfile64:
+    return (FTy.getReturnType()->isPointerTy());
+  case LibFunc::fstat64:
+  case LibFunc::fstatvfs64:
+    return (NumParams == 2 && FTy.getParamType(1)->isPointerTy());
+  case LibFunc::open64:
+    return (NumParams >= 2 && FTy.getParamType(0)->isPointerTy());
+  case LibFunc::gettimeofday:
+    return (NumParams == 2 && FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(1)->isPointerTy());
+
+  case LibFunc::Znwj:                    // new(unsigned int);
+  case LibFunc::Znwm:                    // new(unsigned long);
+  case LibFunc::Znaj:                    // new[](unsigned int);
+  case LibFunc::Znam:                    // new[](unsigned long);
+  case LibFunc::msvc_new_int:            // new(unsigned int);
+  case LibFunc::msvc_new_longlong:       // new(unsigned long long);
+  case LibFunc::msvc_new_array_int:      // new[](unsigned int);
+  case LibFunc::msvc_new_array_longlong: // new[](unsigned long long);
+    return (NumParams == 1);
+
+  case LibFunc::memset_pattern16:
+    return (!FTy.isVarArg() && NumParams == 3 &&
+            isa<PointerType>(FTy.getParamType(0)) &&
+            isa<PointerType>(FTy.getParamType(1)) &&
+            isa<IntegerType>(FTy.getParamType(2)));
+
+  // int __nvvm_reflect(const char *);
+  case LibFunc::nvvm_reflect:
+    return (NumParams == 1 && isa<PointerType>(FTy.getParamType(0)));
+
+  case LibFunc::sin:
+  case LibFunc::sinf:
+  case LibFunc::sinl:
+  case LibFunc::cos:
+  case LibFunc::cosf:
+  case LibFunc::cosl:
+  case LibFunc::exp:
+  case LibFunc::expf:
+  case LibFunc::expl:
+  case LibFunc::exp2:
+  case LibFunc::exp2f:
+  case LibFunc::exp2l:
+  case LibFunc::log:
+  case LibFunc::logf:
+  case LibFunc::logl:
+  case LibFunc::log10:
+  case LibFunc::log10f:
+  case LibFunc::log10l:
+  case LibFunc::log2:
+  case LibFunc::log2f:
+  case LibFunc::log2l:
+  case LibFunc::fabs:
+  case LibFunc::fabsf:
+  case LibFunc::fabsl:
+  case LibFunc::floor:
+  case LibFunc::floorf:
+  case LibFunc::floorl:
+  case LibFunc::ceil:
+  case LibFunc::ceilf:
+  case LibFunc::ceill:
+  case LibFunc::trunc:
+  case LibFunc::truncf:
+  case LibFunc::truncl:
+  case LibFunc::rint:
+  case LibFunc::rintf:
+  case LibFunc::rintl:
+  case LibFunc::nearbyint:
+  case LibFunc::nearbyintf:
+  case LibFunc::nearbyintl:
+  case LibFunc::round:
+  case LibFunc::roundf:
+  case LibFunc::roundl:
+  case LibFunc::sqrt:
+  case LibFunc::sqrtf:
+  case LibFunc::sqrtl:
+    return (NumParams == 1 && FTy.getReturnType()->isFloatingPointTy() &&
+            FTy.getReturnType() == FTy.getParamType(0));
+
+  case LibFunc::fmin:
+  case LibFunc::fminf:
+  case LibFunc::fminl:
+  case LibFunc::fmax:
+  case LibFunc::fmaxf:
+  case LibFunc::fmaxl:
+  case LibFunc::copysign:
+  case LibFunc::copysignf:
+  case LibFunc::copysignl:
+  case LibFunc::pow:
+  case LibFunc::powf:
+  case LibFunc::powl:
+    return (NumParams == 2 && FTy.getReturnType()->isFloatingPointTy() &&
+            FTy.getReturnType() == FTy.getParamType(0) &&
+            FTy.getReturnType() == FTy.getParamType(1));
+
+  case LibFunc::ffs:
+  case LibFunc::ffsl:
+  case LibFunc::ffsll:
+  case LibFunc::isdigit:
+  case LibFunc::isascii:
+  case LibFunc::toascii:
+    return (NumParams == 1 && FTy.getReturnType()->isIntegerTy(32) &&
+            FTy.getParamType(0)->isIntegerTy());
+
+  case LibFunc::fls:
+  case LibFunc::flsl:
+  case LibFunc::flsll:
+  case LibFunc::abs:
+  case LibFunc::labs:
+  case LibFunc::llabs:
+    return (NumParams == 1 && FTy.getReturnType()->isIntegerTy() &&
+            FTy.getReturnType() == FTy.getParamType(0));
+
+  case LibFunc::cxa_atexit:
+    return (NumParams == 3 && FTy.getReturnType()->isIntegerTy() &&
+            FTy.getParamType(0)->isPointerTy() &&
+            FTy.getParamType(1)->isPointerTy() &&
+            FTy.getParamType(2)->isPointerTy());
+
+  case LibFunc::sinpi:
+  case LibFunc::cospi:
+    return (NumParams == 1 && FTy.getReturnType()->isDoubleTy() &&
+            FTy.getReturnType() == FTy.getParamType(0));
+
+  case LibFunc::sinpif:
+  case LibFunc::cospif:
+    return (NumParams == 1 && FTy.getReturnType()->isFloatTy() &&
+            FTy.getReturnType() == FTy.getParamType(0));
+
+  default:
+    // Assume the other functions are correct.
+    // FIXME: It'd be really nice to cover them all.
+    return true;
+  }
+}
+
+bool TargetLibraryInfoImpl::getLibFunc(const Function &FDecl,
+                                       LibFunc::Func &F) const {
+  return getLibFunc(FDecl.getName(), F) &&
+         isValidProtoForLibFunc(*FDecl.getFunctionType(), F);
+}
+
 void TargetLibraryInfoImpl::disableAllFunctions() {
   memset(AvailableArray, 0, sizeof(AvailableArray));
 }
 
 static bool compareByScalarFnName(const VecDesc &LHS, const VecDesc &RHS) {
   return std::strncmp(LHS.ScalarFnName, RHS.ScalarFnName,
                       std::strlen(RHS.ScalarFnName)) < 0;
 }

lib/Analysis/ValueTracking.cpp

case Instruction::Mul: {
     }
   }
   }
 
   // We could not determine if V is a multiple of Base.
   return false;
 }
 
-/// \brief Check call has a unary float signature
-/// It checks following:
-/// a) call should have a single argument
-/// b) argument type should be floating point type
-/// c) call instruction type and argument type should be same
-/// d) call should only reads memory.
-/// If all these condition is met then return ValidIntrinsicID
-/// else return not_intrinsic.
-static Intrinsic::ID checkUnaryFloatSignature(ImmutableCallSite ICS,
-                                              Intrinsic::ID ValidIntrinsicID) {
-  if (ICS.getNumArgOperands() != 1 ||
-      !ICS.getArgOperand(0)->getType()->isFloatingPointTy() ||
-      ICS.getType() != ICS.getArgOperand(0)->getType() ||
-      !ICS.onlyReadsMemory())
-    return Intrinsic::not_intrinsic;
-
-  return ValidIntrinsicID;
-}
-
-/// \brief Check call has a binary float signature
-/// It checks following:
-/// a) call should have 2 arguments.
-/// b) arguments type should be floating point type
-/// c) call instruction type and arguments type should be same
-/// d) call should only reads memory.
-/// If all these condition is met then return ValidIntrinsicID
-/// else return not_intrinsic.
-static Intrinsic::ID checkBinaryFloatSignature(ImmutableCallSite ICS,
-                                               Intrinsic::ID ValidIntrinsicID) {
-  if (ICS.getNumArgOperands() != 2 ||
-      !ICS.getArgOperand(0)->getType()->isFloatingPointTy() ||
-      !ICS.getArgOperand(1)->getType()->isFloatingPointTy() ||
-      ICS.getType() != ICS.getArgOperand(0)->getType() ||
-      ICS.getType() != ICS.getArgOperand(1)->getType() ||
-      !ICS.onlyReadsMemory())
-    return Intrinsic::not_intrinsic;
-
-  return ValidIntrinsicID;
-}
-
 Intrinsic::ID llvm::getIntrinsicForCallSite(ImmutableCallSite ICS,
                                             const TargetLibraryInfo *TLI) {
   const Function *F = ICS.getCalledFunction();
   if (!F)
     return Intrinsic::not_intrinsic;
 
   if (F->isIntrinsic())
     return F->getIntrinsicID();
 
   if (!TLI)
     return Intrinsic::not_intrinsic;
 
   LibFunc::Func Func;
   // We're going to make assumptions on the semantics of the functions, check
   // that the target knows that it's available in this environment and it does
   // not have local linkage.
-  if (!F || F->hasLocalLinkage() || !TLI->getLibFunc(F->getName(), Func))
+  if (!F || F->hasLocalLinkage() || !TLI->getLibFunc(*F, Func))
+    return Intrinsic::not_intrinsic;
+
+  if (!ICS.onlyReadsMemory())
     return Intrinsic::not_intrinsic;
 
   // Otherwise check if we have a call to a function that can be turned into a
   // vector intrinsic.
   switch (Func) {
   default:
     break;
   case LibFunc::sin:
   case LibFunc::sinf:
   case LibFunc::sinl:
-    return checkUnaryFloatSignature(ICS, Intrinsic::sin);
+    return Intrinsic::sin;
   case LibFunc::cos:
   case LibFunc::cosf:
   case LibFunc::cosl:
-    return checkUnaryFloatSignature(ICS, Intrinsic::cos);
+    return Intrinsic::cos;
   case LibFunc::exp:
   case LibFunc::expf:
   case LibFunc::expl:
-    return checkUnaryFloatSignature(ICS, Intrinsic::exp);
+    return Intrinsic::exp;
   case LibFunc::exp2:
   case LibFunc::exp2f:
   case LibFunc::exp2l:
-    return checkUnaryFloatSignature(ICS, Intrinsic::exp2);
+    return Intrinsic::exp2;
   case LibFunc::log:
   case LibFunc::logf:
   case LibFunc::logl:
-    return checkUnaryFloatSignature(ICS, Intrinsic::log);
+    return Intrinsic::log;
   case LibFunc::log10:
   case LibFunc::log10f:
   case LibFunc::log10l:
-    return checkUnaryFloatSignature(ICS, Intrinsic::log10);
+    return Intrinsic::log10;
   case LibFunc::log2:
   case LibFunc::log2f:
   case LibFunc::log2l:
-    return checkUnaryFloatSignature(ICS, Intrinsic::log2);
+    return Intrinsic::log2;
   case LibFunc::fabs:
   case LibFunc::fabsf:
   case LibFunc::fabsl:
-    return checkUnaryFloatSignature(ICS, Intrinsic::fabs);
+    return Intrinsic::fabs;
   case LibFunc::fmin:
   case LibFunc::fminf:
   case LibFunc::fminl:
-    return checkBinaryFloatSignature(ICS, Intrinsic::minnum);
+    return Intrinsic::minnum;
   case LibFunc::fmax:
   case LibFunc::fmaxf:
   case LibFunc::fmaxl:
-    return checkBinaryFloatSignature(ICS, Intrinsic::maxnum);
+    return Intrinsic::maxnum;
   case LibFunc::copysign:
   case LibFunc::copysignf:
   case LibFunc::copysignl:
-    return checkBinaryFloatSignature(ICS, Intrinsic::copysign);
+    return Intrinsic::copysign;
   case LibFunc::floor:
   case LibFunc::floorf:
   case LibFunc::floorl:
-    return checkUnaryFloatSignature(ICS, Intrinsic::floor);
+    return Intrinsic::floor;
   case LibFunc::ceil:
   case LibFunc::ceilf:
   case LibFunc::ceill:
-    return checkUnaryFloatSignature(ICS, Intrinsic::ceil);
+    return Intrinsic::ceil;
   case LibFunc::trunc:
   case LibFunc::truncf:
   case LibFunc::truncl:
-    return checkUnaryFloatSignature(ICS, Intrinsic::trunc);
+    return Intrinsic::trunc;
   case LibFunc::rint:
   case LibFunc::rintf:
   case LibFunc::rintl:
-    return checkUnaryFloatSignature(ICS, Intrinsic::rint);
+    return Intrinsic::rint;
   case LibFunc::nearbyint:
   case LibFunc::nearbyintf:
   case LibFunc::nearbyintl:
-    return checkUnaryFloatSignature(ICS, Intrinsic::nearbyint);
+    return Intrinsic::nearbyint;
   case LibFunc::round:
   case LibFunc::roundf:
   case LibFunc::roundl:
-    return checkUnaryFloatSignature(ICS, Intrinsic::round);
+    return Intrinsic::round;
   case LibFunc::pow:
   case LibFunc::powf:
   case LibFunc::powl:
-    return checkBinaryFloatSignature(ICS, Intrinsic::pow);
+    return Intrinsic::pow;
   case LibFunc::sqrt:
   case LibFunc::sqrtf:
   case LibFunc::sqrtl:
     if (ICS->hasNoNaNs())
-      return checkUnaryFloatSignature(ICS, Intrinsic::sqrt);
+      return Intrinsic::sqrt;
     return Intrinsic::not_intrinsic;
   }
 
   return Intrinsic::not_intrinsic;
 }
 
 /// Return true if we can prove that the specified FP value is never equal to
 /// -0.0.

lib/Transforms/IPO/GlobalOpt.cpp

bool GlobalOpt::OptimizeGlobalAliases(Module &M) {
   }
 
   Used.syncVariablesAndSets();
 
   return Changed;
 }
 
 static Function *FindCXAAtExit(Module &M, TargetLibraryInfo *TLI) {
-  if (!TLI->has(LibFunc::cxa_atexit))
+  LibFunc::Func F = LibFunc::cxa_atexit;
+  if (!TLI->has(F))
     return nullptr;
 
-  Function *Fn = M.getFunction(TLI->getName(LibFunc::cxa_atexit));
-
+  Function *Fn = M.getFunction(TLI->getName(F));
   if (!Fn)
     return nullptr;
 
-  FunctionType *FTy = Fn->getFunctionType();
-
-  // Checking that the function has the right return type, the right number of
-  // parameters and that they all have pointer types should be enough.
-  if (!FTy->getReturnType()->isIntegerTy() ||
-      FTy->getNumParams() != 3 ||
-      !FTy->getParamType(0)->isPointerTy() ||
-      !FTy->getParamType(1)->isPointerTy() ||
-      !FTy->getParamType(2)->isPointerTy())
+  // Make sure that the function has the correct prototype.
+  if (!TLI->getLibFunc(*Fn, F) || F != LibFunc::cxa_atexit)
     return nullptr;
 
   return Fn;
 }
 
 /// Returns whether the given function is an empty C++ destructor and can
 /// therefore be eliminated.
 /// Note that we assume that other optimization passes have already simplified

lib/Transforms/IPO/InferFunctionAttrs.cpp

 /// attributes.
 ///
 /// Returns true if any attributes were set and false otherwise.
 static bool inferPrototypeAttributes(Function &F,
                                      const TargetLibraryInfo &TLI) {
   if (F.hasFnAttribute(Attribute::OptimizeNone))
     return false;
 
-  FunctionType *FTy = F.getFunctionType();
   LibFunc::Func TheLibFunc;
-  if (!(TLI.getLibFunc(F.getName(), TheLibFunc) && TLI.has(TheLibFunc)))
+  if (!(TLI.getLibFunc(F, TheLibFunc) && TLI.has(TheLibFunc)))
     return false;
 
   bool Changed = false;
   switch (TheLibFunc) {
   case LibFunc::strlen:
-    if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
-      return false;
     Changed |= setOnlyReadsMemory(F);
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     return Changed;
   case LibFunc::strchr:
   case LibFunc::strrchr:
-    if (FTy->getNumParams() != 2 || !FTy->getParamType(0)->isPointerTy() ||
-        !FTy->getParamType(1)->isIntegerTy())
-      return false;
     Changed |= setOnlyReadsMemory(F);
     Changed |= setDoesNotThrow(F);
     return Changed;
   case LibFunc::strtol:
   case LibFunc::strtod:
   case LibFunc::strtof:
   case LibFunc::strtoul:
   case LibFunc::strtoll:
   case LibFunc::strtold:
   case LibFunc::strtoull:
-    if (FTy->getNumParams() < 2 || !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 2);
     Changed |= setOnlyReadsMemory(F, 1);
     return Changed;
   case LibFunc::strcpy:
   case LibFunc::stpcpy:
   case LibFunc::strcat:
   case LibFunc::strncat:
   case LibFunc::strncpy:
   case LibFunc::stpncpy:
-    if (FTy->getNumParams() < 2 || !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 2);
     Changed |= setOnlyReadsMemory(F, 2);
     return Changed;
   case LibFunc::strxfrm:
-    if (FTy->getNumParams() != 3 || !FTy->getParamType(0)->isPointerTy() ||
-        !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setDoesNotCapture(F, 2);
     Changed |= setOnlyReadsMemory(F, 2);
     return Changed;
   case LibFunc::strcmp:      // 0,1
   case LibFunc::strspn:      // 0,1
   case LibFunc::strncmp:     // 0,1
   case LibFunc::strcspn:     // 0,1
   case LibFunc::strcoll:     // 0,1
   case LibFunc::strcasecmp:  // 0,1
   case LibFunc::strncasecmp: //
-    if (FTy->getNumParams() < 2 || !FTy->getParamType(0)->isPointerTy() ||
-        !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setOnlyReadsMemory(F);
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setDoesNotCapture(F, 2);
     return Changed;
   case LibFunc::strstr:
   case LibFunc::strpbrk:
-    if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setOnlyReadsMemory(F);
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 2);
     return Changed;
   case LibFunc::strtok:
   case LibFunc::strtok_r:
-    if (FTy->getNumParams() < 2 || !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 2);
     Changed |= setOnlyReadsMemory(F, 2);
     return Changed;
   case LibFunc::scanf:
-    if (FTy->getNumParams() < 1 || !FTy->getParamType(0)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setOnlyReadsMemory(F, 1);
     return Changed;
   case LibFunc::setbuf:
   case LibFunc::setvbuf:
-    if (FTy->getNumParams() < 1 || !FTy->getParamType(0)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     return Changed;
   case LibFunc::strdup:
   case LibFunc::strndup:
-    if (FTy->getNumParams() < 1 || !FTy->getReturnType()->isPointerTy() ||
-        !FTy->getParamType(0)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotAlias(F, 0);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setOnlyReadsMemory(F, 1);
     return Changed;
   case LibFunc::stat:
   case LibFunc::statvfs:
-    if (FTy->getNumParams() < 2 || !FTy->getParamType(0)->isPointerTy() ||
-        !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setDoesNotCapture(F, 2);
     Changed |= setOnlyReadsMemory(F, 1);
     return Changed;
   case LibFunc::sscanf:
-    if (FTy->getNumParams() < 2 || !FTy->getParamType(0)->isPointerTy() ||
-        !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setDoesNotCapture(F, 2);
     Changed |= setOnlyReadsMemory(F, 1);
     Changed |= setOnlyReadsMemory(F, 2);
     return Changed;
   case LibFunc::sprintf:
-    if (FTy->getNumParams() < 2 || !FTy->getParamType(0)->isPointerTy() ||
-        !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setDoesNotCapture(F, 2);
     Changed |= setOnlyReadsMemory(F, 2);
     return Changed;
   case LibFunc::snprintf:
-    if (FTy->getNumParams() != 3 || !FTy->getParamType(0)->isPointerTy() ||
-        !FTy->getParamType(2)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setDoesNotCapture(F, 3);
     Changed |= setOnlyReadsMemory(F, 3);
     return Changed;
   case LibFunc::setitimer:
-    if (FTy->getNumParams() != 3 || !FTy->getParamType(1)->isPointerTy() ||
-        !FTy->getParamType(2)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 2);
     Changed |= setDoesNotCapture(F, 3);
     Changed |= setOnlyReadsMemory(F, 2);
     return Changed;
   case LibFunc::system:
-    if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
-      return false;
     // May throw; "system" is a valid pthread cancellation point.
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setOnlyReadsMemory(F, 1);
     return Changed;
   case LibFunc::malloc:
-    if (FTy->getNumParams() != 1 || !FTy->getReturnType()->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotAlias(F, 0);
     return Changed;
   case LibFunc::memcmp:
-    if (FTy->getNumParams() != 3 || !FTy->getParamType(0)->isPointerTy() ||
-        !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setOnlyReadsMemory(F);
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setDoesNotCapture(F, 2);
     return Changed;
   case LibFunc::memchr:
   case LibFunc::memrchr:
-    if (FTy->getNumParams() != 3)
-      return false;
     Changed |= setOnlyReadsMemory(F);
     Changed |= setDoesNotThrow(F);
     return Changed;
   case LibFunc::modf:
   case LibFunc::modff:
   case LibFunc::modfl:
-    if (FTy->getNumParams() < 2 || !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 2);
     return Changed;
   case LibFunc::memcpy:
   case LibFunc::memccpy:
   case LibFunc::memmove:
-    if (FTy->getNumParams() < 2 || !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 2);
     Changed |= setOnlyReadsMemory(F, 2);
     return Changed;
   case LibFunc::memalign:
-    if (!FTy->getReturnType()->isPointerTy())
-      return false;
     Changed |= setDoesNotAlias(F, 0);
     return Changed;
   case LibFunc::mkdir:
-    if (FTy->getNumParams() == 0 || !FTy->getParamType(0)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setOnlyReadsMemory(F, 1);
     return Changed;
   case LibFunc::mktime:
-    if (FTy->getNumParams() == 0 || !FTy->getParamType(0)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     return Changed;
   case LibFunc::realloc:
-    if (FTy->getNumParams() != 2 || !FTy->getParamType(0)->isPointerTy() ||
-        !FTy->getReturnType()->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotAlias(F, 0);
     Changed |= setDoesNotCapture(F, 1);
     return Changed;
   case LibFunc::read:
-    if (FTy->getNumParams() != 3 || !FTy->getParamType(1)->isPointerTy())
-      return false;
     // May throw; "read" is a valid pthread cancellation point.
     Changed |= setDoesNotCapture(F, 2);
     return Changed;
   case LibFunc::rewind:
-    if (FTy->getNumParams() < 1 || !FTy->getParamType(0)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     return Changed;
   case LibFunc::rmdir:
   case LibFunc::remove:
   case LibFunc::realpath:
-    if (FTy->getNumParams() < 1 || !FTy->getParamType(0)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setOnlyReadsMemory(F, 1);
     return Changed;
   case LibFunc::rename:
-    if (FTy->getNumParams() < 2 || !FTy->getParamType(0)->isPointerTy() ||
-        !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setDoesNotCapture(F, 2);
     Changed |= setOnlyReadsMemory(F, 1);
     Changed |= setOnlyReadsMemory(F, 2);
     return Changed;
   case LibFunc::readlink:
-    if (FTy->getNumParams() < 2 || !FTy->getParamType(0)->isPointerTy() ||
-        !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setDoesNotCapture(F, 2);
     Changed |= setOnlyReadsMemory(F, 1);
     return Changed;
   case LibFunc::write:
-    if (FTy->getNumParams() != 3 || !FTy->getParamType(1)->isPointerTy())
-      return false;
     // May throw; "write" is a valid pthread cancellation point.
     Changed |= setDoesNotCapture(F, 2);
     Changed |= setOnlyReadsMemory(F, 2);
     return Changed;
   case LibFunc::bcopy:
-    if (FTy->getNumParams() != 3 || !FTy->getParamType(0)->isPointerTy() ||
-        !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setDoesNotCapture(F, 2);
     Changed |= setOnlyReadsMemory(F, 1);
     return Changed;
   case LibFunc::bcmp:
-    if (FTy->getNumParams() != 3 || !FTy->getParamType(0)->isPointerTy() ||
-        !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setOnlyReadsMemory(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setDoesNotCapture(F, 2);
     return Changed;
   case LibFunc::bzero:
-    if (FTy->getNumParams() != 2 || !FTy->getParamType(0)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     return Changed;
   case LibFunc::calloc:
-    if (FTy->getNumParams() != 2 || !FTy->getReturnType()->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotAlias(F, 0);
     return Changed;
   case LibFunc::chmod:
   case LibFunc::chown:
-    if (FTy->getNumParams() == 0 || !FTy->getParamType(0)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setOnlyReadsMemory(F, 1);
     return Changed;
   case LibFunc::ctermid:
   case LibFunc::clearerr:
   case LibFunc::closedir:
-    if (FTy->getNumParams() == 0 || !FTy->getParamType(0)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     return Changed;
   case LibFunc::atoi:
   case LibFunc::atol:
   case LibFunc::atof:
   case LibFunc::atoll:
-    if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setOnlyReadsMemory(F);
     Changed |= setDoesNotCapture(F, 1);
     return Changed;
   case LibFunc::access:
-    if (FTy->getNumParams() != 2 || !FTy->getParamType(0)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setOnlyReadsMemory(F, 1);
     return Changed;
   case LibFunc::fopen:
-    if (FTy->getNumParams() != 2 || !FTy->getReturnType()->isPointerTy() ||
-        !FTy->getParamType(0)->isPointerTy() ||
-        !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotAlias(F, 0);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setDoesNotCapture(F, 2);
     Changed |= setOnlyReadsMemory(F, 1);
     Changed |= setOnlyReadsMemory(F, 2);
     return Changed;
   case LibFunc::fdopen:
-    if (FTy->getNumParams() != 2 || !FTy->getReturnType()->isPointerTy() ||
-        !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotAlias(F, 0);
     Changed |= setDoesNotCapture(F, 2);
     Changed |= setOnlyReadsMemory(F, 2);
     return Changed;
   case LibFunc::feof:
   case LibFunc::free:
   case LibFunc::fseek:
   case LibFunc::ftell:
   case LibFunc::fgetc:
   case LibFunc::fseeko:
   case LibFunc::ftello:
   case LibFunc::fileno:
   case LibFunc::fflush:
   case LibFunc::fclose:
   case LibFunc::fsetpos:
   case LibFunc::flockfile:
   case LibFunc::funlockfile:
   case LibFunc::ftrylockfile:
-    if (FTy->getNumParams() == 0 || !FTy->getParamType(0)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     return Changed;
   case LibFunc::ferror:
-    if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setOnlyReadsMemory(F);
     return Changed;
   case LibFunc::fputc:
   case LibFunc::fstat:
   case LibFunc::frexp:
   case LibFunc::frexpf:
   case LibFunc::frexpl:
   case LibFunc::fstatvfs:
-    if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 2);
     return Changed;
   case LibFunc::fgets:
-    if (FTy->getNumParams() != 3 || !FTy->getParamType(0)->isPointerTy() ||
-        !FTy->getParamType(2)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 3);
     return Changed;
   case LibFunc::fread:
-    if (FTy->getNumParams() != 4 || !FTy->getParamType(0)->isPointerTy() ||
-        !FTy->getParamType(3)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setDoesNotCapture(F, 4);
     return Changed;
   case LibFunc::fwrite:
-    if (FTy->getNumParams() != 4 || !FTy->getParamType(0)->isPointerTy() ||
-        !FTy->getParamType(3)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setDoesNotCapture(F, 4);
     return Changed;
   case LibFunc::fputs:
-    if (FTy->getNumParams() < 2 || !FTy->getParamType(0)->isPointerTy() ||
-        !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setDoesNotCapture(F, 2);
     Changed |= setOnlyReadsMemory(F, 1);
     return Changed;
   case LibFunc::fscanf:
   case LibFunc::fprintf:
-    if (FTy->getNumParams() < 2 || !FTy->getParamType(0)->isPointerTy() ||
-        !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setDoesNotCapture(F, 2);
     Changed |= setOnlyReadsMemory(F, 2);
     return Changed;
   case LibFunc::fgetpos:
-    if (FTy->getNumParams() < 2 || !FTy->getParamType(0)->isPointerTy() ||
-        !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setDoesNotCapture(F, 2);
     return Changed;
   case LibFunc::getc:
   case LibFunc::getlogin_r:
   case LibFunc::getc_unlocked:
-    if (FTy->getNumParams() == 0 || !FTy->getParamType(0)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     return Changed;
   case LibFunc::getenv:
-    if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setOnlyReadsMemory(F);
     Changed |= setDoesNotCapture(F, 1);
     return Changed;
   case LibFunc::gets:
   case LibFunc::getchar:
     Changed |= setDoesNotThrow(F);
     return Changed;
   case LibFunc::getitimer:
-    if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 2);
     return Changed;
   case LibFunc::getpwnam:
-    if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setOnlyReadsMemory(F, 1);
     return Changed;
   case LibFunc::ungetc:
-    if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 2);
     return Changed;
   case LibFunc::uname:
-    if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     return Changed;
   case LibFunc::unlink:
-    if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setOnlyReadsMemory(F, 1);
     return Changed;
   case LibFunc::unsetenv:
-    if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setOnlyReadsMemory(F, 1);
     return Changed;
   case LibFunc::utime:
   case LibFunc::utimes:
-    if (FTy->getNumParams() != 2 || !FTy->getParamType(0)->isPointerTy() ||
-        !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setDoesNotCapture(F, 2);
     Changed |= setOnlyReadsMemory(F, 1);
     Changed |= setOnlyReadsMemory(F, 2);
     return Changed;
   case LibFunc::putc:
-    if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 2);
     return Changed;
   case LibFunc::puts:
   case LibFunc::printf:
   case LibFunc::perror:
-    if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setOnlyReadsMemory(F, 1);
     return Changed;
   case LibFunc::pread:
-    if (FTy->getNumParams() != 4 || !FTy->getParamType(1)->isPointerTy())
-      return false;
     // May throw; "pread" is a valid pthread cancellation point.
     Changed |= setDoesNotCapture(F, 2);
     return Changed;
   case LibFunc::pwrite:
-    if (FTy->getNumParams() != 4 || !FTy->getParamType(1)->isPointerTy())
-      return false;
     // May throw; "pwrite" is a valid pthread cancellation point.
     Changed |= setDoesNotCapture(F, 2);
     Changed |= setOnlyReadsMemory(F, 2);
     return Changed;
   case LibFunc::putchar:
     Changed |= setDoesNotThrow(F);
     return Changed;
   case LibFunc::popen:
-    if (FTy->getNumParams() != 2 || !FTy->getReturnType()->isPointerTy() ||
-        !FTy->getParamType(0)->isPointerTy() ||
-        !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotAlias(F, 0);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setDoesNotCapture(F, 2);
     Changed |= setOnlyReadsMemory(F, 1);
     Changed |= setOnlyReadsMemory(F, 2);
     return Changed;
   case LibFunc::pclose:
-    if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     return Changed;
   case LibFunc::vscanf:
-    if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setOnlyReadsMemory(F, 1);
     return Changed;
   case LibFunc::vsscanf:
-    if (FTy->getNumParams() != 3 || !FTy->getParamType(1)->isPointerTy() ||
-        !FTy->getParamType(2)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setDoesNotCapture(F, 2);
     Changed |= setOnlyReadsMemory(F, 1);
     Changed |= setOnlyReadsMemory(F, 2);
     return Changed;
   case LibFunc::vfscanf:
-    if (FTy->getNumParams() != 3 || !FTy->getParamType(1)->isPointerTy() ||
-        !FTy->getParamType(2)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setDoesNotCapture(F, 2);
     Changed |= setOnlyReadsMemory(F, 2);
     return Changed;
   case LibFunc::valloc:
-    if (!FTy->getReturnType()->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotAlias(F, 0);
     return Changed;
   case LibFunc::vprintf:
-    if (FTy->getNumParams() != 2 || !FTy->getParamType(0)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setOnlyReadsMemory(F, 1);
     return Changed;
   case LibFunc::vfprintf:
   case LibFunc::vsprintf:
-    if (FTy->getNumParams() != 3 || !FTy->getParamType(0)->isPointerTy() ||
-        !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setDoesNotCapture(F, 2);
     Changed |= setOnlyReadsMemory(F, 2);
     return Changed;
   case LibFunc::vsnprintf:
-    if (FTy->getNumParams() != 4 || !FTy->getParamType(0)->isPointerTy() ||
-        !FTy->getParamType(2)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setDoesNotCapture(F, 3);
     Changed |= setOnlyReadsMemory(F, 3);
     return Changed;
   case LibFunc::open:
-    if (FTy->getNumParams() < 2 || !FTy->getParamType(0)->isPointerTy())
-      return false;
     // May throw; "open" is a valid pthread cancellation point.
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setOnlyReadsMemory(F, 1);
     return Changed;
   case LibFunc::opendir:
-    if (FTy->getNumParams() != 1 || !FTy->getReturnType()->isPointerTy() ||
-        !FTy->getParamType(0)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotAlias(F, 0);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setOnlyReadsMemory(F, 1);
     return Changed;
   case LibFunc::tmpfile:
-    if (!FTy->getReturnType()->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotAlias(F, 0);
     return Changed;
   case LibFunc::times:
-    if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     return Changed;
   case LibFunc::htonl:
   case LibFunc::htons:
   case LibFunc::ntohl:
   case LibFunc::ntohs:
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotAccessMemory(F);
     return Changed;
   case LibFunc::lstat:
-    if (FTy->getNumParams() != 2 || !FTy->getParamType(0)->isPointerTy() ||
-        !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setDoesNotCapture(F, 2);
     Changed |= setOnlyReadsMemory(F, 1);
     return Changed;
   case LibFunc::lchown:
-    if (FTy->getNumParams() != 3 || !FTy->getParamType(0)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setOnlyReadsMemory(F, 1);
     return Changed;
   case LibFunc::qsort:
-    if (FTy->getNumParams() != 4 || !FTy->getParamType(3)->isPointerTy())
-      return false;
     // May throw; places call through function pointer.
     Changed |= setDoesNotCapture(F, 4);
     return Changed;
   case LibFunc::dunder_strdup:
   case LibFunc::dunder_strndup:
-    if (FTy->getNumParams() < 1 || !FTy->getReturnType()->isPointerTy() ||
-        !FTy->getParamType(0)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotAlias(F, 0);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setOnlyReadsMemory(F, 1);
     return Changed;
   case LibFunc::dunder_strtok_r:
-    if (FTy->getNumParams() != 3 || !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 2);
     Changed |= setOnlyReadsMemory(F, 2);
     return Changed;
   case LibFunc::under_IO_getc:
-    if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     return Changed;
   case LibFunc::under_IO_putc:
-    if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 2);
     return Changed;
   case LibFunc::dunder_isoc99_scanf:
-    if (FTy->getNumParams() < 1 || !FTy->getParamType(0)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setOnlyReadsMemory(F, 1);
     return Changed;
   case LibFunc::stat64:
   case LibFunc::lstat64:
   case LibFunc::statvfs64:
-    if (FTy->getNumParams() < 1 || !FTy->getParamType(0)->isPointerTy() ||
-        !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setDoesNotCapture(F, 2);
     Changed |= setOnlyReadsMemory(F, 1);
     return Changed;
   case LibFunc::dunder_isoc99_sscanf:
-    if (FTy->getNumParams() < 1 || !FTy->getParamType(0)->isPointerTy() ||
-        !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setDoesNotCapture(F, 2);
     Changed |= setOnlyReadsMemory(F, 1);
     Changed |= setOnlyReadsMemory(F, 2);
     return Changed;
   case LibFunc::fopen64:
-    if (FTy->getNumParams() != 2 || !FTy->getReturnType()->isPointerTy() ||
-        !FTy->getParamType(0)->isPointerTy() ||
-        !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotAlias(F, 0);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setDoesNotCapture(F, 2);
     Changed |= setOnlyReadsMemory(F, 1);
     Changed |= setOnlyReadsMemory(F, 2);
     return Changed;
   case LibFunc::fseeko64:
   case LibFunc::ftello64:
-    if (FTy->getNumParams() == 0 || !FTy->getParamType(0)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     return Changed;
   case LibFunc::tmpfile64:
-    if (!FTy->getReturnType()->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotAlias(F, 0);
     return Changed;
   case LibFunc::fstat64:
   case LibFunc::fstatvfs64:
-    if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
-      return false;
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 2);
     return Changed;
   case LibFunc::open64:
-    if (FTy->getNumParams() < 2 || !FTy->getParamType(0)->isPointerTy())
-      return false;
     // May throw; "open" is a valid pthread cancellation point.
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setOnlyReadsMemory(F, 1);
     return Changed;
   case LibFunc::gettimeofday:
-    if (FTy->getNumParams() != 2 || !FTy->getParamType(0)->isPointerTy() ||
-        !FTy->getParamType(1)->isPointerTy())
-      return false;
     // Currently some platforms have the restrict keyword on the arguments to
     // gettimeofday. To be conservative, do not add noalias to gettimeofday's
     // arguments.
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotCapture(F, 1);
     Changed |= setDoesNotCapture(F, 2);
     return Changed;
-
   case LibFunc::Znwj: // new(unsigned int)
   case LibFunc::Znwm: // new(unsigned long)
   case LibFunc::Znaj: // new[](unsigned int)
   case LibFunc::Znam: // new[](unsigned long)
   case LibFunc::msvc_new_int: // new(unsigned int)
   case LibFunc::msvc_new_longlong: // new(unsigned long long)
   case LibFunc::msvc_new_array_int: // new[](unsigned int)
   case LibFunc::msvc_new_array_longlong: // new[](unsigned long long)
-    if (FTy->getNumParams() != 1)
-      return false;
     // Operator new always returns a nonnull noalias pointer
     Changed |= setNonNull(F, AttributeSet::ReturnIndex);
     Changed |= setDoesNotAlias(F, AttributeSet::ReturnIndex);
     return Changed;
-
   //TODO: add LibFunc entries for:
   //case LibFunc::memset_pattern4:
   //case LibFunc::memset_pattern8:
   case LibFunc::memset_pattern16:
-    if (FTy->isVarArg() || FTy->getNumParams() != 3 ||
-        !isa<PointerType>(FTy->getParamType(0)) ||
-        !isa<PointerType>(FTy->getParamType(1)) ||
-        !isa<IntegerType>(FTy->getParamType(2)))
-      return false;
-
     Changed |= setOnlyAccessesArgMemory(F);
     Changed |= setOnlyReadsMemory(F, 2);
     return Changed;
-
   // int __nvvm_reflect(const char *)
   case LibFunc::nvvm_reflect:
-    if (FTy->getNumParams() != 1 || !isa<PointerType>(FTy->getParamType(0)))
-      return false;
-
     Changed |= setDoesNotAccessMemory(F);
     Changed |= setDoesNotThrow(F);
     return Changed;
 
   default:
     // FIXME: It'd be really nice to cover all the library functions we're
     // aware of here.
     return false;

lib/Transforms/Utils/SimplifyLibCalls.cpp

case Type::FloatTyID:
     return TLI->has(FloatFn);
   case Type::DoubleTyID:
     return TLI->has(DoubleFn);
   default:
     return TLI->has(LongDoubleFn);
   }
 }
 
-/// \brief Returns whether \p F matches the signature expected for the
-/// string/memory copying library function \p Func.
-/// Acceptable functions are st[rp][n]?cpy, memove, memcpy, and memset.
-/// Their fortified (_chk) counterparts are also accepted.
-static bool checkStringCopyLibFuncSignature(Function *F, LibFunc::Func Func) {
-  const DataLayout &DL = F->getParent()->getDataLayout();
-  FunctionType *FT = F->getFunctionType();
-  LLVMContext &Context = F->getContext();
-  Type *PCharTy = Type::getInt8PtrTy(Context);
-  Type *SizeTTy = DL.getIntPtrType(Context);
-  unsigned NumParams = FT->getNumParams();
-
-  // All string libfuncs return the same type as the first parameter.
-  if (FT->getReturnType() != FT->getParamType(0))
-    return false;
-
-  switch (Func) {
-  default:
-    llvm_unreachable("Can't check signature for non-string-copy libfunc.");
-  case LibFunc::stpncpy_chk:
-  case LibFunc::strncpy_chk:
-    --NumParams; // fallthrough
-  case LibFunc::stpncpy:
-  case LibFunc::strncpy: {
-    if (NumParams != 3 || FT->getParamType(0) != FT->getParamType(1) ||
-        FT->getParamType(0) != PCharTy || !FT->getParamType(2)->isIntegerTy())
-      return false;
-    break;
-  }
-  case LibFunc::strcpy_chk:
-  case LibFunc::stpcpy_chk:
-    --NumParams; // fallthrough
-  case LibFunc::stpcpy:
-  case LibFunc::strcpy: {
-    if (NumParams != 2 || FT->getParamType(0) != FT->getParamType(1) ||
-        FT->getParamType(0) != PCharTy)
-      return false;
-    break;
-  }
-  case LibFunc::memmove_chk:
-  case LibFunc::memcpy_chk:
-    --NumParams; // fallthrough
-  case LibFunc::memmove:
-  case LibFunc::memcpy: {
-    if (NumParams != 3 || !FT->getParamType(0)->isPointerTy() ||
-        !FT->getParamType(1)->isPointerTy() || FT->getParamType(2) != SizeTTy)
-      return false;
-    break;
-  }
-  case LibFunc::memset_chk:
-    --NumParams; // fallthrough
-  case LibFunc::memset: {
-    if (NumParams != 3 || !FT->getParamType(0)->isPointerTy() ||
-        !FT->getParamType(1)->isIntegerTy() || FT->getParamType(2) != SizeTTy)
-      return false;
-    break;
-  }
-  }
-  // If this is a fortified libcall, the last parameter is a size_t.
-  if (NumParams == FT->getNumParams() - 1)
-    return FT->getParamType(FT->getNumParams() - 1) == SizeTTy;
-  return true;
-}
-
 //===----------------------------------------------------------------------===//
 // String and Memory Library Call Optimizations
 //===----------------------------------------------------------------------===//
 
 Value *LibCallSimplifier::optimizeStrCat(CallInst *CI, IRBuilder<> &B) {
-  Function *Callee = CI->getCalledFunction();
-  // 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 nullptr;
-
   // 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 nullptr;
Value *LibCallSimplifier::emitStrLenMemCpy(Value *Src, Value *Dst, uint64_t Len,
   // concatenation for us.  Make a memcpy to copy the nul byte with align = 1.
   B.CreateMemCpy(CpyDst, Src,
                  ConstantInt::get(DL.getIntPtrType(Src->getContext()), Len + 1),
                  1);
   return Dst;
 }
 
 Value *LibCallSimplifier::optimizeStrNCat(CallInst *CI, IRBuilder<> &B) {
-  Function *Callee = CI->getCalledFunction();
-  // 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 nullptr;
-
   // 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();
Value *LibCallSimplifier::optimizeStrNCat(CallInst *CI, IRBuilder<> &B) {
 
   // strncat(x, s, c) -> strcat(x, s)
   // s is constant so the strcat can be optimized further.
   return emitStrLenMemCpy(Src, Dst, SrcLen, B);
 }
 
 Value *LibCallSimplifier::optimizeStrChr(CallInst *CI, IRBuilder<> &B) {
   Function *Callee = CI->getCalledFunction();
-  // 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 nullptr;
-
   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) {
     uint64_t Len = GetStringLength(SrcStr);
     if (Len == 0 || !FT->getParamType(1)->isIntegerTy(32)) // memchr needs i32.
Value *LibCallSimplifier::optimizeStrChr(CallInst *CI, IRBuilder<> &B) {
   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(B.getInt8Ty(), SrcStr, B.getInt64(I), "strchr");
 }
 
 Value *LibCallSimplifier::optimizeStrRChr(CallInst *CI, IRBuilder<> &B) {
-  Function *Callee = CI->getCalledFunction();
-  // 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 nullptr;
-
   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 nullptr;
 
   StringRef Str;
Value *LibCallSimplifier::optimizeStrRChr(CallInst *CI, IRBuilder<> &B) {
   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(B.getInt8Ty(), SrcStr, B.getInt64(I), "strrchr");
 }
 
 Value *LibCallSimplifier::optimizeStrCmp(CallInst *CI, IRBuilder<> &B) {
-  Function *Callee = CI->getCalledFunction();
-  // 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 nullptr;
-
   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);
 
return emitMemCmp(Str1P, Str2P,
                                        std::min(Len1, Len2)),
                       B, DL, TLI);
   }
 
   return nullptr;
 }
 
 Value *LibCallSimplifier::optimizeStrNCmp(CallInst *CI, IRBuilder<> &B) {
-  Function *Callee = CI->getCalledFunction();
-  // 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 nullptr;
-
   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();
Value *LibCallSimplifier::optimizeStrNCmp(CallInst *CI, IRBuilder<> &B) {
 
   if (HasStr2 && Str2.empty()) // strncmp(x, "", n) -> *x
     return B.CreateZExt(B.CreateLoad(Str1P, "strcmpload"), CI->getType());
 
   return nullptr;
 }
 
 Value *LibCallSimplifier::optimizeStrCpy(CallInst *CI, IRBuilder<> &B) {
-  Function *Callee = CI->getCalledFunction();
-
-  if (!checkStringCopyLibFuncSignature(Callee, LibFunc::strcpy))
-    return nullptr;
-
   Value *Dst = CI->getArgOperand(0), *Src = CI->getArgOperand(1);
   if (Dst == Src) // strcpy(x,x)  -> x
     return Src;
 
   // See if we can get the length of the input string.
   uint64_t Len = GetStringLength(Src);
   if (Len == 0)
     return nullptr;
 
   // 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(DL.getIntPtrType(CI->getContext()), Len), 1);
   return Dst;
 }
 
 Value *LibCallSimplifier::optimizeStpCpy(CallInst *CI, IRBuilder<> &B) {
   Function *Callee = CI->getCalledFunction();
-  if (!checkStringCopyLibFuncSignature(Callee, LibFunc::stpcpy))
-    return nullptr;
-
   Value *Dst = CI->getArgOperand(0), *Src = CI->getArgOperand(1);
   if (Dst == Src) { // stpcpy(x,x)  -> x+strlen(x)
     Value *StrLen = emitStrLen(Src, B, DL, TLI);
     return StrLen ? B.CreateInBoundsGEP(B.getInt8Ty(), Dst, StrLen) : nullptr;
   }
 
   // See if we can get the length of the input string.
   uint64_t Len = GetStringLength(Src);
   if (Len == 0)
     return nullptr;
 
   Type *PT = Callee->getFunctionType()->getParamType(0);
   Value *LenV = ConstantInt::get(DL.getIntPtrType(PT), Len);
   Value *DstEnd = B.CreateGEP(B.getInt8Ty(), Dst,
                               ConstantInt::get(DL.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;
 }
 
 Value *LibCallSimplifier::optimizeStrNCpy(CallInst *CI, IRBuilder<> &B) {
   Function *Callee = CI->getCalledFunction();
-  if (!checkStringCopyLibFuncSignature(Callee, LibFunc::strncpy))
-    return nullptr;
-
   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 nullptr;
Value *LibCallSimplifier::optimizeStrNCpy(CallInst *CI, IRBuilder<> &B) {
   Type *PT = Callee->getFunctionType()->getParamType(0);
   // strncpy(x, s, c) -> memcpy(x, s, c, 1) [s and c are constant]
   B.CreateMemCpy(Dst, Src, ConstantInt::get(DL.getIntPtrType(PT), Len), 1);
 
   return Dst;
 }
 
 Value *LibCallSimplifier::optimizeStrLen(CallInst *CI, IRBuilder<> &B) {
-  Function *Callee = CI->getCalledFunction();
-  FunctionType *FT = Callee->getFunctionType();
-  if (FT->getNumParams() != 1 || FT->getParamType(0) != B.getInt8PtrTy() ||
-      !FT->getReturnType()->isIntegerTy())
-    return nullptr;
-
   Value *Src = CI->getArgOperand(0);
 
   // Constant folding: strlen("xyz") -> 3
   if (uint64_t Len = GetStringLength(Src))
     return ConstantInt::get(CI->getType(), Len - 1);
 
   // If s is a constant pointer pointing to a string literal, we can fold
   // strlen(s + x) to strlen(s) - x, when x is known to be in the range 
Value *LibCallSimplifier::optimizeStrLen(CallInst *CI, IRBuilder<> &B) {
   // strlen(x) == 0 --> *x == 0
   if (isOnlyUsedInZeroEqualityComparison(CI))
     return B.CreateZExt(B.CreateLoad(Src, "strlenfirst"), CI->getType());
 
   return nullptr;
 }
 
 Value *LibCallSimplifier::optimizeStrPBrk(CallInst *CI, IRBuilder<> &B) {
-  Function *Callee = CI->getCalledFunction();
-  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 nullptr;
-
   StringRef S1, S2;
   bool HasS1 = getConstantStringInfo(CI->getArgOperand(0), S1);
   bool HasS2 = getConstantStringInfo(CI->getArgOperand(1), S2);
 
   // strpbrk(s, "") -> nullptr
   // strpbrk("", s) -> nullptr
   if ((HasS1 && S1.empty()) || (HasS2 && S2.empty()))
     return Constant::getNullValue(CI->getType());
Value *LibCallSimplifier::optimizeStrPBrk(CallInst *CI, IRBuilder<> &B) {
   // strpbrk(s, "a") -> strchr(s, 'a')
   if (HasS2 && S2.size() == 1)
     return emitStrChr(CI->getArgOperand(0), S2[0], B, TLI);
 
   return nullptr;
 }
 
 Value *LibCallSimplifier::optimizeStrTo(CallInst *CI, IRBuilder<> &B) {
-  Function *Callee = CI->getCalledFunction();
-  FunctionType *FT = Callee->getFunctionType();
-  if ((FT->getNumParams() != 2 && FT->getNumParams() != 3) ||
-      !FT->getParamType(0)->isPointerTy() ||
-      !FT->getParamType(1)->isPointerTy())
-    return nullptr;
-
   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, Attribute::NoCapture);
   }
 
   return nullptr;
 }
 
 Value *LibCallSimplifier::optimizeStrSpn(CallInst *CI, IRBuilder<> &B) {
-  Function *Callee = CI->getCalledFunction();
-  FunctionType *FT = Callee->getFunctionType();
-  if (FT->getNumParams() != 2 || FT->getParamType(0) != B.getInt8PtrTy() ||
-      FT->getParamType(1) != FT->getParamType(0) ||
-      !FT->getReturnType()->isIntegerTy())
-    return nullptr;
-
   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 nullptr;
 }
 
 Value *LibCallSimplifier::optimizeStrCSpn(CallInst *CI, IRBuilder<> &B) {
-  Function *Callee = CI->getCalledFunction();
-  FunctionType *FT = Callee->getFunctionType();
-  if (FT->getNumParams() != 2 || FT->getParamType(0) != B.getInt8PtrTy() ||
-      FT->getParamType(1) != FT->getParamType(0) ||
-      !FT->getReturnType()->isIntegerTy())
-    return nullptr;
-
   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 (HasS2 && S2.empty())
     return emitStrLen(CI->getArgOperand(0), B, DL, TLI);
 
   return nullptr;
 }
 
 Value *LibCallSimplifier::optimizeStrStr(CallInst *CI, IRBuilder<> &B) {
-  Function *Callee = CI->getCalledFunction();
-  FunctionType *FT = Callee->getFunctionType();
-  if (FT->getNumParams() != 2 || !FT->getParamType(0)->isPointerTy() ||
-      !FT->getParamType(1)->isPointerTy() ||
-      !FT->getReturnType()->isPointerTy())
-    return nullptr;
-
   // 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 (isOnlyUsedInEqualityComparison(CI, CI->getArgOperand(0))) {
     Value *StrLen = emitStrLen(CI->getArgOperand(1), B, DL, TLI);
     if (!StrLen)
Value *LibCallSimplifier::optimizeStrStr(CallInst *CI, IRBuilder<> &B) {
   if (HasStr2 && ToFindStr.size() == 1) {
     Value *StrChr = emitStrChr(CI->getArgOperand(0), ToFindStr[0], B, TLI);
     return StrChr ? B.CreateBitCast(StrChr, CI->getType()) : nullptr;
   }
   return nullptr;
 }
 
 Value *LibCallSimplifier::optimizeMemChr(CallInst *CI, IRBuilder<> &B) {
-  Function *Callee = CI->getCalledFunction();
-  FunctionType *FT = Callee->getFunctionType();
-  if (FT->getNumParams() != 3 || !FT->getParamType(0)->isPointerTy() ||
-      !FT->getParamType(1)->isIntegerTy(32) ||
-      !FT->getParamType(2)->isIntegerTy() ||
-      !FT->getReturnType()->isPointerTy())
-    return nullptr;
-
   Value *SrcStr = CI->getArgOperand(0);
   ConstantInt *CharC = dyn_cast<ConstantInt>(CI->getArgOperand(1));
   ConstantInt *LenC = dyn_cast<ConstantInt>(CI->getArgOperand(2));
 
   // memchr(x, y, 0) -> null
   if (LenC && LenC->isNullValue())
     return Constant::getNullValue(CI->getType());
 
Value *LibCallSimplifier::optimizeMemChr(CallInst *CI, IRBuilder<> &B) {
   if (I == StringRef::npos) // Didn't find the char.  memchr returns null.
     return Constant::getNullValue(CI->getType());
 
   // memchr(s+n,c,l) -> gep(s+n+i,c)
   return B.CreateGEP(B.getInt8Ty(), SrcStr, B.getInt64(I), "memchr");
 }
 
 Value *LibCallSimplifier::optimizeMemCmp(CallInst *CI, IRBuilder<> &B) {
-  Function *Callee = CI->getCalledFunction();
-  FunctionType *FT = Callee->getFunctionType();
-  if (FT->getNumParams() != 3 || !FT->getParamType(0)->isPointerTy() ||
-      !FT->getParamType(1)->isPointerTy() ||
-      !FT->getReturnType()->isIntegerTy(32))
-    return nullptr;
-
   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)
else if (Cmp > 0)
       Ret = 1;
     return ConstantInt::get(CI->getType(), Ret);
   }
 
   return nullptr;
 }
 
 Value *LibCallSimplifier::optimizeMemCpy(CallInst *CI, IRBuilder<> &B) {
-  Function *Callee = CI->getCalledFunction();
-
-  if (!checkStringCopyLibFuncSignature(Callee, LibFunc::memcpy))
-    return nullptr;
-
   // 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);
 }
 
 Value *LibCallSimplifier::optimizeMemMove(CallInst *CI, IRBuilder<> &B) {
-  Function *Callee = CI->getCalledFunction();
-
-  if (!checkStringCopyLibFuncSignature(Callee, LibFunc::memmove))
-    return nullptr;
-
   // 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);
 }
 
 // TODO: Does this belong in BuildLibCalls or should all of those similar
 // functions be moved here?
static Value *foldMallocMemset(CallInst *Memset, IRBuilder<> &B,
   // place of a memset library call.
   auto *Malloc = dyn_cast<CallInst>(Memset->getArgOperand(0));
   if (!Malloc || !Malloc->hasOneUse())
     return nullptr;
 
   // Is the inner call really malloc()?
   Function *InnerCallee = Malloc->getCalledFunction();
   LibFunc::Func Func;
-  if (!TLI.getLibFunc(InnerCallee->getName(), Func) || !TLI.has(Func) ||
+  if (!TLI.getLibFunc(*InnerCallee, Func) || !TLI.has(Func) ||
       Func != LibFunc::malloc)
     return nullptr;
 
-  // Matching the name is not good enough. Make sure the parameter and return
-  // type match the standard library signature.
-  FunctionType *FT = InnerCallee->getFunctionType();
-  if (FT->getNumParams() != 1 || !FT->getParamType(0)->isIntegerTy())
-    return nullptr;
-
-  auto *RetType = dyn_cast<PointerType>(FT->getReturnType());
-  if (!RetType || !RetType->getPointerElementType()->isIntegerTy(8))
-    return nullptr;
-
   // The memset must cover the same number of bytes that are malloc'd.
   if (Memset->getArgOperand(2) != Malloc->getArgOperand(0))
     return nullptr;
 
   // Replace the malloc with a calloc. We need the data layout to know what the
   // actual size of a 'size_t' parameter is. 
   B.SetInsertPoint(Malloc->getParent(), ++Malloc->getIterator());
   const DataLayout &DL = Malloc->getModule()->getDataLayout();
   IntegerType *SizeType = DL.getIntPtrType(B.GetInsertBlock()->getContext());
   Value *Calloc = emitCalloc(ConstantInt::get(SizeType, 1),
                              Malloc->getArgOperand(0), Malloc->getAttributes(),
                              B, TLI);
   if (!Calloc)
     return nullptr;
 
   Malloc->replaceAllUsesWith(Calloc);
   Malloc->eraseFromParent();
 
   return Calloc;
 }
 
 Value *LibCallSimplifier::optimizeMemSet(CallInst *CI, IRBuilder<> &B) {
-  Function *Callee = CI->getCalledFunction();
-
-  if (!checkStringCopyLibFuncSignature(Callee, LibFunc::memset))
-    return nullptr;
-
   if (auto *Calloc = foldMallocMemset(CI, B, *TLI))
     return Calloc;
 
   // 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);
 }
if (ConstantFP *Const = dyn_cast<ConstantFP>(Val)) {
     (void)F.convert(APFloat::IEEEsingle, APFloat::rmNearestTiesToEven,
                     &losesInfo);
     if (!losesInfo)
       return ConstantFP::get(Const->getContext(), F);
   }
   return nullptr;
 }
 
-/// Any floating-point library function that we're trying to simplify will have
-/// a signature of the form: fptype foo(fptype param1, fptype param2, ...).
-/// CheckDoubleTy indicates that 'fptype' must be 'double'.
-static bool matchesFPLibFunctionSignature(const Function *F, unsigned NumParams,
-                                          bool CheckDoubleTy) {
-  FunctionType *FT = F->getFunctionType();
-  if (FT->getNumParams() != NumParams)
-    return false;
-
-  // The return type must match what we're looking for.
-  Type *RetTy = FT->getReturnType();
-  if (CheckDoubleTy ? !RetTy->isDoubleTy() : !RetTy->isFloatingPointTy())
-    return false;
-
-  // Each parameter must match the return type, and therefore, match every other
-  // parameter too.
-  for (const Type *ParamTy : FT->params())
-    if (ParamTy != RetTy)
-      return false;
-
-  return true;
-}
-
 /// Shrink double -> float for unary functions like 'floor'.
 static Value *optimizeUnaryDoubleFP(CallInst *CI, IRBuilder<> &B,
                                     bool CheckRetType) {
   Function *Callee = CI->getCalledFunction();
-  if (!matchesFPLibFunctionSignature(Callee, 1, true))
+  // We know this libcall has a valid prototype, but we don't know which.
+  if (!CI->getType()->isDoubleTy())
     return nullptr;
 
   if (CheckRetType) {
     // Check if all the uses for function like 'sin' are converted to float.
     for (User *U : CI->users()) {
       FPTruncInst *Cast = dyn_cast<FPTruncInst>(U);
       if (!Cast || !Cast->getType()->isFloatTy())
         return nullptr;
static Value *optimizeUnaryDoubleFP(CallInst *CI, IRBuilder<> &B,
   }
 
   return B.CreateFPExt(V, B.getDoubleTy());
 }
 
 /// Shrink double -> float for binary functions like 'fmin/fmax'.
 static Value *optimizeBinaryDoubleFP(CallInst *CI, IRBuilder<> &B) {
   Function *Callee = CI->getCalledFunction();
-  if (!matchesFPLibFunctionSignature(Callee, 2, true))
+  // We know this libcall has a valid prototype, but we don't know which.
+  if (!CI->getType()->isDoubleTy())
     return nullptr;
 
   // If this is something like 'fmin((double)floatval1, (double)floatval2)',
   // or fmin(1.0, (double)floatval), then we convert it to fminf.
   Value *V1 = valueHasFloatPrecision(CI->getArgOperand(0));
   if (V1 == nullptr)
     return nullptr;
   Value *V2 = valueHasFloatPrecision(CI->getArgOperand(1));
static Value *optimizeBinaryDoubleFP(CallInst *CI, IRBuilder<> &B) {
   // TODO: Handle intrinsics in the same way as in optimizeUnaryDoubleFP().
   Value *V = emitBinaryFloatFnCall(V1, V2, Callee->getName(), B,
                                    Callee->getAttributes());
   return B.CreateFPExt(V, B.getDoubleTy());
 }
 
 Value *LibCallSimplifier::optimizeCos(CallInst *CI, IRBuilder<> &B) {
   Function *Callee = CI->getCalledFunction();
-  if (!matchesFPLibFunctionSignature(Callee, 1, false))
-    return nullptr;
-
   Value *Ret = nullptr;
   StringRef Name = Callee->getName();
   if (UnsafeFPShrink && Name == "cos" && hasFloatVersion(Name))
     Ret = optimizeUnaryDoubleFP(CI, B, true);
 
   // cos(-x) -> cos(x)
   Value *Op1 = CI->getArgOperand(0);
   if (BinaryOperator::isFNeg(Op1)) {
static Value *getPow(Value *InnerChain[33], unsigned Exp, IRBuilder<> &B) {
 
   InnerChain[Exp] = B.CreateFMul(getPow(InnerChain, AddChain[Exp][0], B),
                                  getPow(InnerChain, AddChain[Exp][1], B));
   return InnerChain[Exp];
 }
 
 Value *LibCallSimplifier::optimizePow(CallInst *CI, IRBuilder<> &B) {
   Function *Callee = CI->getCalledFunction();
-  if (!matchesFPLibFunctionSignature(Callee, 2, false))
-    return nullptr;
-
   Value *Ret = nullptr;
   StringRef Name = Callee->getName();
   if (UnsafeFPShrink && Name == "pow" && hasFloatVersion(Name))
     Ret = optimizeUnaryDoubleFP(CI, B, true);
 
   Value *Op1 = CI->getArgOperand(0), *Op2 = CI->getArgOperand(1);
   if (ConstantFP *Op1C = dyn_cast<ConstantFP>(Op1)) {
     // pow(1.0, x) -> 1.0
if (CI->hasUnsafeAlgebra()) {
     return FMul;
   }
 
   return nullptr;
 }
 
 Value *LibCallSimplifier::optimizeExp2(CallInst *CI, IRBuilder<> &B) {
   Function *Callee = CI->getCalledFunction();
-  if (!matchesFPLibFunctionSignature(Callee, 1, false))
-    return nullptr;
-
   Value *Ret = nullptr;
   StringRef Name = Callee->getName();
   if (UnsafeFPShrink && Name == "exp2" && hasFloatVersion(Name))
     Ret = optimizeUnaryDoubleFP(CI, B, true);
 
   Value *Op = CI->getArgOperand(0);
   // Turn exp2(sitofp(x)) -> ldexp(1.0, sext(x))  if sizeof(x) <= 32
   // Turn exp2(uitofp(x)) -> ldexp(1.0, zext(x))  if sizeof(x) < 32
if (LdExpArg) {
       return CI;
     }
   }
   return Ret;
 }
 
 Value *LibCallSimplifier::optimizeFabs(CallInst *CI, IRBuilder<> &B) {
   Function *Callee = CI->getCalledFunction();
-  if (!matchesFPLibFunctionSignature(Callee, 1, false))
-    return nullptr;
-
   Value *Ret = nullptr;
   StringRef Name = Callee->getName();
   if (Name == "fabs" && hasFloatVersion(Name))
     Ret = optimizeUnaryDoubleFP(CI, B, false);
 
   Value *Op = CI->getArgOperand(0);
   if (Instruction *I = dyn_cast<Instruction>(Op)) {
     // Fold fabs(x * x) -> x * x; any squared FP value must already be positive.
     if (I->getOpcode() == Instruction::FMul)
       if (I->getOperand(0) == I->getOperand(1))
         return Op;
   }
   return Ret;
 }
 
 Value *LibCallSimplifier::optimizeFMinFMax(CallInst *CI, IRBuilder<> &B) {
   Function *Callee = CI->getCalledFunction();
-  if (!matchesFPLibFunctionSignature(Callee, 2, false))
-    return nullptr;
-
   // If we can shrink the call to a float function rather than a double
   // function, do that first.
   StringRef Name = Callee->getName();
   if ((Name == "fmin" || Name == "fmax") && hasFloatVersion(Name))
     if (Value *Ret = optimizeBinaryDoubleFP(CI, B))
       return Ret;
 
   IRBuilder<>::FastMathFlagGuard Guard(B);
Value *LibCallSimplifier::optimizeFMinFMax(CallInst *CI, IRBuilder<> &B) {
   Value *Op1 = CI->getArgOperand(1);
   Value *Cmp = Callee->getName().startswith("fmin") ?
     B.CreateFCmpOLT(Op0, Op1) : B.CreateFCmpOGT(Op0, Op1);
   return B.CreateSelect(Cmp, Op0, Op1);
 }
 
 Value *LibCallSimplifier::optimizeLog(CallInst *CI, IRBuilder<> &B) {
   Function *Callee = CI->getCalledFunction();
-  if (!matchesFPLibFunctionSignature(Callee, 1, false))
-    return nullptr;
-
   Value *Ret = nullptr;
   StringRef Name = Callee->getName();
   if (UnsafeFPShrink && hasFloatVersion(Name))
     Ret = optimizeUnaryDoubleFP(CI, B, true);
 
   if (!CI->hasUnsafeAlgebra())
     return Ret;
   Value *Op1 = CI->getArgOperand(0);
return B.CreateFMul(
         emitUnaryFloatFnCall(ConstantFP::get(CI->getType(), 2.0),
                              Callee->getName(), B, Callee->getAttributes()),
         "logmul");
   return Ret;
 }
 
 Value *LibCallSimplifier::optimizeSqrt(CallInst *CI, IRBuilder<> &B) {
   Function *Callee = CI->getCalledFunction();
-  if (!matchesFPLibFunctionSignature(Callee, 1, false))
-    return nullptr;
-
   Value *Ret = nullptr;
   if (TLI->has(LibFunc::sqrtf) && (Callee->getName() == "sqrt" ||
                                    Callee->getIntrinsicID() == Intrinsic::sqrt))
     Ret = optimizeUnaryDoubleFP(CI, B, true);
 
   if (!CI->hasUnsafeAlgebra())
     return Ret;
 
if (OtherOp) {
     return B.CreateFMul(FabsCall, SqrtCall);
   }
   return FabsCall;
 }
 
 // TODO: Generalize to handle any trig function and its inverse.
 Value *LibCallSimplifier::optimizeTan(CallInst *CI, IRBuilder<> &B) {
   Function *Callee = CI->getCalledFunction();
-  if (!matchesFPLibFunctionSignature(Callee, 1, false))
-    return nullptr;
-
   Value *Ret = nullptr;
   StringRef Name = Callee->getName();
   if (UnsafeFPShrink && Name == "tan" && hasFloatVersion(Name))
     Ret = optimizeUnaryDoubleFP(CI, B, true);
 
   Value *Op1 = CI->getArgOperand(0);
   auto *OpC = dyn_cast<CallInst>(Op1);
   if (!OpC)
if (F && TLI->getLibFunc(F->getName(), Func) && TLI->has(Func) &&
       ((Func == LibFunc::atan && Callee->getName() == "tan") ||
        (Func == LibFunc::atanf && Callee->getName() == "tanf") ||
        (Func == LibFunc::atanl && Callee->getName() == "tanl")))
     Ret = OpC->getArgOperand(0);
   return Ret;
 }
 
 static bool isTrigLibCall(CallInst *CI) {
-  Function *Callee = CI->getCalledFunction();
-  FunctionType *FT = Callee->getFunctionType();
-
   // We can only hope to do anything useful if we can ignore things like errno
   // and floating-point exceptions.
-  bool AttributesSafe =
-  CI->hasFnAttr(Attribute::NoUnwind) && CI->hasFnAttr(Attribute::ReadNone);
-
-  // Other than that we need float(float) or double(double)
-  return AttributesSafe && FT->getNumParams() == 1 &&
-  FT->getReturnType() == FT->getParamType(0) &&
-  (FT->getParamType(0)->isFloatTy() ||
-   FT->getParamType(0)->isDoubleTy());
+  // We already checked the prototype.
+  return CI->hasFnAttr(Attribute::NoUnwind) &&
+         CI->hasFnAttr(Attribute::ReadNone);
 }
 
 static void insertSinCosCall(IRBuilder<> &B, Function *OrigCallee, Value *Arg,
                              bool UseFloat, Value *&Sin, Value *&Cos,
                              Value *&SinCos) {
   Type *ArgTy = Arg->getType();
   Type *ResTy;
   StringRef Name;
if (!CI)
     return;
 
   // Don't consider calls in other functions.
   if (CI->getFunction() != F)
     return;
 
   Function *Callee = CI->getCalledFunction();
   LibFunc::Func Func;
-  if (!Callee || !TLI->getLibFunc(Callee->getName(), Func) || !TLI->has(Func) ||
+  if (!Callee || !TLI->getLibFunc(*Callee, Func) || !TLI->has(Func) ||
       !isTrigLibCall(CI))
     return;
 
   if (IsFloat) {
     if (Func == LibFunc::sinpif)
       SinCalls.push_back(CI);
     else if (Func == LibFunc::cospif)
       CosCalls.push_back(CI);
void LibCallSimplifier::replaceTrigInsts(SmallVectorImpl<CallInst *> &Calls,
   for (CallInst *C : Calls)
     replaceAllUsesWith(C, Res);
 }
 
 //===----------------------------------------------------------------------===//
 // Integer Library Call Optimizations
 //===----------------------------------------------------------------------===//
 
-static bool checkIntUnaryReturnAndParam(Function *Callee) {
-  FunctionType *FT = Callee->getFunctionType();
-  return FT->getNumParams() == 1 && FT->getReturnType()->isIntegerTy(32) &&
-    FT->getParamType(0)->isIntegerTy();
-}
-
 Value *LibCallSimplifier::optimizeFFS(CallInst *CI, IRBuilder<> &B) {
   Function *Callee = CI->getCalledFunction();
-  if (!checkIntUnaryReturnAndParam(Callee))
-    return nullptr;
   Value *Op = CI->getArgOperand(0);
 
   // Constant fold.
   if (ConstantInt *CI = dyn_cast<ConstantInt>(Op)) {
     if (CI->isZero()) // ffs(0) -> 0.
       return B.getInt32(0);
     // ffs(c) -> cttz(c)+1
     return B.getInt32(CI->getValue().countTrailingZeros() + 1);
   }
 
   // ffs(x) -> x != 0 ? (i32)llvm.cttz(x)+1 : 0
   Type *ArgType = Op->getType();
   Value *F =
       Intrinsic::getDeclaration(Callee->getParent(), Intrinsic::cttz, ArgType);
   Value *V = B.CreateCall(F, {Op, B.getTrue()}, "cttz");
   V = B.CreateAdd(V, ConstantInt::get(V->getType(), 1));
   V = B.CreateIntCast(V, B.getInt32Ty(), false);
 
   Value *Cond = B.CreateICmpNE(Op, Constant::getNullValue(ArgType));
   return B.CreateSelect(Cond, V, B.getInt32(0));
 }
 
 Value *LibCallSimplifier::optimizeAbs(CallInst *CI, IRBuilder<> &B) {
-  Function *Callee = CI->getCalledFunction();
-  FunctionType *FT = Callee->getFunctionType();
-  // We require integer(integer) where the types agree.
-  if (FT->getNumParams() != 1 || !FT->getReturnType()->isIntegerTy() ||
-      FT->getParamType(0) != FT->getReturnType())
-    return nullptr;
-
   // abs(x) -> x >s -1 ? x : -x
   Value *Op = CI->getArgOperand(0);
   Value *Pos =
       B.CreateICmpSGT(Op, Constant::getAllOnesValue(Op->getType()), "ispos");
   Value *Neg = B.CreateNeg(Op, "neg");
   return B.CreateSelect(Pos, Op, Neg);
 }
 
 Value *LibCallSimplifier::optimizeIsDigit(CallInst *CI, IRBuilder<> &B) {
-  if (!checkIntUnaryReturnAndParam(CI->getCalledFunction()))
-    return nullptr;
-
   // isdigit(c) -> (c-'0') <u 10
   Value *Op = CI->getArgOperand(0);
   Op = B.CreateSub(Op, B.getInt32('0'), "isdigittmp");
   Op = B.CreateICmpULT(Op, B.getInt32(10), "isdigit");
   return B.CreateZExt(Op, CI->getType());
 }
 
 Value *LibCallSimplifier::optimizeIsAscii(CallInst *CI, IRBuilder<> &B) {
-  if (!checkIntUnaryReturnAndParam(CI->getCalledFunction()))
-    return nullptr;
-
   // isascii(c) -> c <u 128
   Value *Op = CI->getArgOperand(0);
   Op = B.CreateICmpULT(Op, B.getInt32(128), "isascii");
   return B.CreateZExt(Op, CI->getType());
 }
 
 Value *LibCallSimplifier::optimizeToAscii(CallInst *CI, IRBuilder<> &B) {
-  if (!checkIntUnaryReturnAndParam(CI->getCalledFunction()))
-    return nullptr;
-
   // toascii(c) -> c & 0x7f
   return B.CreateAnd(CI->getArgOperand(0),
                      ConstantInt::get(CI->getType(), 0x7F));
 }
 
 //===----------------------------------------------------------------------===//
 // Formatting and IO Library Call Optimizations
 //===----------------------------------------------------------------------===//
 
 static bool isReportingError(Function *Callee, CallInst *CI, int StreamArg);
 
 Value *LibCallSimplifier::optimizeErrorReporting(CallInst *CI, IRBuilder<> &B,
                                                  int StreamArg) {
+  Function *Callee = CI->getCalledFunction();
   // Error reporting calls should be cold, mark them as such.
   // This applies even to non-builtin calls: it is only a hint and applies to
   // functions that the frontend might not understand as builtins.
 
   // This heuristic was suggested in:
   // Improving Static Branch Prediction in a Compiler
   // Brian L. Deitrich, Ben-Chung Cheng, Wen-mei W. Hwu
   // Proceedings of PACT'98, Oct. 1998, IEEE
-  Function *Callee = CI->getCalledFunction();
-
   if (!CI->hasFnAttr(Attribute::Cold) &&
       isReportingError(Callee, CI, StreamArg)) {
     CI->addAttribute(AttributeSet::FunctionIndex, Attribute::Cold);
   }
 
   return nullptr;
 }
 
if (FormatStr == "%s\n" && CI->getNumArgOperands() > 1 &&
       CI->getArgOperand(1)->getType()->isPointerTy())
     return emitPutS(CI->getArgOperand(1), B, TLI);
   return nullptr;
 }
 
 Value *LibCallSimplifier::optimizePrintF(CallInst *CI, IRBuilder<> &B) {
 
   Function *Callee = CI->getCalledFunction();
-  // Require one fixed pointer argument and an integer/void result.
   FunctionType *FT = Callee->getFunctionType();
-  if (FT->getNumParams() < 1 || !FT->getParamType(0)->isPointerTy() ||
-      !(FT->getReturnType()->isIntegerTy() || FT->getReturnType()->isVoidTy()))
-    return nullptr;
-
   if (Value *V = optimizePrintFString(CI, B)) {
     return V;
   }
 
   // printf(format, ...) -> iprintf(format, ...) if no floating point
   // arguments.
   if (TLI->has(LibFunc::iprintf) && !callHasFloatingPointArgument(CI)) {
     Module *M = B.GetInsertBlock()->getParent()->getParent();
if (FormatStr[1] == 's') {
     // The sprintf result is the unincremented number of bytes in the string.
     return B.CreateIntCast(Len, CI->getType(), false);
   }
   return nullptr;
 }
 
 Value *LibCallSimplifier::optimizeSPrintF(CallInst *CI, IRBuilder<> &B) {
   Function *Callee = CI->getCalledFunction();
-  // Require two fixed pointer arguments and an integer result.
   FunctionType *FT = Callee->getFunctionType();
-  if (FT->getNumParams() != 2 || !FT->getParamType(0)->isPointerTy() ||
-      !FT->getParamType(1)->isPointerTy() ||
-      !FT->getReturnType()->isIntegerTy())
-    return nullptr;
-
   if (Value *V = optimizeSPrintFString(CI, B)) {
     return V;
   }
 
   // sprintf(str, format, ...) -> siprintf(str, format, ...) if no floating
   // point arguments.
   if (TLI->has(LibFunc::siprintf) && !callHasFloatingPointArgument(CI)) {
     Module *M = B.GetInsertBlock()->getParent()->getParent();
if (!CI->getArgOperand(2)->getType()->isPointerTy())
       return nullptr;
     return emitFPutS(CI->getArgOperand(2), CI->getArgOperand(0), B, TLI);
   }
   return nullptr;
 }
 
 Value *LibCallSimplifier::optimizeFPrintF(CallInst *CI, IRBuilder<> &B) {
   Function *Callee = CI->getCalledFunction();
-  // Require two fixed paramters as pointers and integer result.
   FunctionType *FT = Callee->getFunctionType();
-  if (FT->getNumParams() != 2 || !FT->getParamType(0)->isPointerTy() ||
-      !FT->getParamType(1)->isPointerTy() ||
-      !FT->getReturnType()->isIntegerTy())
-    return nullptr;
-
   if (Value *V = optimizeFPrintFString(CI, B)) {
     return V;
   }
 
   // fprintf(stream, format, ...) -> fiprintf(stream, format, ...) if no
   // floating point arguments.
   if (TLI->has(LibFunc::fiprintf) && !callHasFloatingPointArgument(CI)) {
     Module *M = B.GetInsertBlock()->getParent()->getParent();
     Constant *FIPrintFFn =
         M->getOrInsertFunction("fiprintf", FT, Callee->getAttributes());
     CallInst *New = cast<CallInst>(CI->clone());
     New->setCalledFunction(FIPrintFFn);
     B.Insert(New);
     return New;
   }
   return nullptr;
 }
 
 Value *LibCallSimplifier::optimizeFWrite(CallInst *CI, IRBuilder<> &B) {
   optimizeErrorReporting(CI, B, 3);
 
-  Function *Callee = CI->getCalledFunction();
-  // Require a pointer, an integer, an integer, a pointer, returning integer.
-  FunctionType *FT = Callee->getFunctionType();
-  if (FT->getNumParams() != 4 || !FT->getParamType(0)->isPointerTy() ||
-      !FT->getParamType(1)->isIntegerTy() ||
-      !FT->getParamType(2)->isIntegerTy() ||
-      !FT->getParamType(3)->isPointerTy() ||
-      !FT->getReturnType()->isIntegerTy())
-    return nullptr;
-
   // Get the element size and count.
   ConstantInt *SizeC = dyn_cast<ConstantInt>(CI->getArgOperand(1));
   ConstantInt *CountC = dyn_cast<ConstantInt>(CI->getArgOperand(2));
   if (!SizeC || !CountC)
     return nullptr;
   uint64_t Bytes = SizeC->getZExtValue() * CountC->getZExtValue();
 
   // If this is writing zero records, remove the call (it's a noop).
Value *LibCallSimplifier::optimizeFWrite(CallInst *CI, IRBuilder<> &B) {
   }
 
   return nullptr;
 }
 
 Value *LibCallSimplifier::optimizeFPuts(CallInst *CI, IRBuilder<> &B) {
   optimizeErrorReporting(CI, B, 1);
 
-  Function *Callee = CI->getCalledFunction();
-
-  // Require two pointers.  Also, we can't optimize if return value is used.
-  FunctionType *FT = Callee->getFunctionType();
-  if (FT->getNumParams() != 2 || !FT->getParamType(0)->isPointerTy() ||
-      !FT->getParamType(1)->isPointerTy() || !CI->use_empty())
+  // We can't optimize if return value is used.
+  if (!CI->use_empty())
     return nullptr;
 
   // fputs(s,F) --> fwrite(s,1,strlen(s),F)
   uint64_t Len = GetStringLength(CI->getArgOperand(0));
   if (!Len)
     return nullptr;
 
   // Known to have no uses (see above).
   return emitFWrite(
       CI->getArgOperand(0),
       ConstantInt::get(DL.getIntPtrType(CI->getContext()), Len - 1),
       CI->getArgOperand(1), B, DL, TLI);
 }
 
 Value *LibCallSimplifier::optimizePuts(CallInst *CI, IRBuilder<> &B) {
-  Function *Callee = CI->getCalledFunction();
-  // Require one fixed pointer argument and an integer/void result.
-  FunctionType *FT = Callee->getFunctionType();
-  if (FT->getNumParams() < 1 || !FT->getParamType(0)->isPointerTy() ||
-      !(FT->getReturnType()->isIntegerTy() || FT->getReturnType()->isVoidTy()))
-    return nullptr;
-
   // Check for a constant string.
   StringRef Str;
   if (!getConstantStringInfo(CI->getArgOperand(0), Str))
     return nullptr;
 
   if (Str.empty() && CI->use_empty()) {
     // puts("") -> putchar('\n')
     Value *Res = emitPutChar(B.getInt32('\n'), B, TLI);
if (TLI->getLibFunc(FloatFuncName, Func))
     return TLI->has(Func);
   return false;
 }
 
 Value *LibCallSimplifier::optimizeStringMemoryLibCall(CallInst *CI,
                                                       IRBuilder<> &Builder) {
   LibFunc::Func Func;
   Function *Callee = CI->getCalledFunction();
-  StringRef FuncName = Callee->getName();
-
   // Check for string/memory library functions.
-  if (TLI->getLibFunc(FuncName, Func) && TLI->has(Func)) {
+  if (TLI->getLibFunc(*Callee, Func) && TLI->has(Func)) {
     // Make sure we never change the calling convention.
     assert((ignoreCallingConv(Func) ||
             CI->getCallingConv() == llvm::CallingConv::C) &&
       "Optimizing string/memory libcall would change the calling convention");
     switch (Func) {
     case LibFunc::strcat:
       return optimizeStrCat(CI, Builder);
     case LibFunc::strncat:
if (SimplifiedCI && SimplifiedCI->getCalledFunction()) {
         SimplifiedCI->eraseFromParent();
         return V;
       }
     }
     return SimplifiedFortifiedCI;
   }
 
   // Then check for known library functions.
-  if (TLI->getLibFunc(FuncName, Func) && TLI->has(Func)) {
+  if (TLI->getLibFunc(*Callee, Func) && TLI->has(Func)) {
     // We never change the calling convention.
     if (!ignoreCallingConv(Func) && !isCallingConvC)
       return nullptr;
     if (Value *V = optimizeStringMemoryLibCall(CI, Builder))
       return V;
     switch (Func) {
     case LibFunc::cosf:
     case LibFunc::cos:
if (ConstantInt *ObjSizeCI =
     if (ConstantInt *SizeCI = dyn_cast<ConstantInt>(CI->getArgOperand(SizeOp)))
       return ObjSizeCI->getZExtValue() >= SizeCI->getZExtValue();
   }
   return false;
 }
 
 Value *FortifiedLibCallSimplifier::optimizeMemCpyChk(CallInst *CI,
                                                      IRBuilder<> &B) {
-  Function *Callee = CI->getCalledFunction();
-
-  if (!checkStringCopyLibFuncSignature(Callee, LibFunc::memcpy_chk))
-    return nullptr;
-
   if (isFortifiedCallFoldable(CI, 3, 2, false)) {
     B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(1),
                    CI->getArgOperand(2), 1);
     return CI->getArgOperand(0);
   }
   return nullptr;
 }
 
 Value *FortifiedLibCallSimplifier::optimizeMemMoveChk(CallInst *CI,
                                                       IRBuilder<> &B) {
-  Function *Callee = CI->getCalledFunction();
-
-  if (!checkStringCopyLibFuncSignature(Callee, LibFunc::memmove_chk))
-    return nullptr;
-
   if (isFortifiedCallFoldable(CI, 3, 2, false)) {
     B.CreateMemMove(CI->getArgOperand(0), CI->getArgOperand(1),
                     CI->getArgOperand(2), 1);
     return CI->getArgOperand(0);
   }
   return nullptr;
 }
 
 Value *FortifiedLibCallSimplifier::optimizeMemSetChk(CallInst *CI,
                                                      IRBuilder<> &B) {
-  Function *Callee = CI->getCalledFunction();
-
-  if (!checkStringCopyLibFuncSignature(Callee, LibFunc::memset_chk))
-    return nullptr;
-
   // TODO: Try foldMallocMemset() here.
 
   if (isFortifiedCallFoldable(CI, 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 nullptr;
 }
 
 Value *FortifiedLibCallSimplifier::optimizeStrpCpyChk(CallInst *CI,
                                                       IRBuilder<> &B,
                                                       LibFunc::Func Func) {
   Function *Callee = CI->getCalledFunction();
   StringRef Name = Callee->getName();
   const DataLayout &DL = CI->getModule()->getDataLayout();
-
-  if (!checkStringCopyLibFuncSignature(Callee, Func))
-    return nullptr;
-
   Value *Dst = CI->getArgOperand(0), *Src = CI->getArgOperand(1),
         *ObjSize = CI->getArgOperand(2);
 
   // __stpcpy_chk(x,x,...)  -> x+strlen(x)
   if (Func == LibFunc::stpcpy_chk && !OnlyLowerUnknownSize && Dst == Src) {
     Value *StrLen = emitStrLen(Src, B, DL, TLI);
     return StrLen ? B.CreateInBoundsGEP(B.getInt8Ty(), Dst, StrLen) : nullptr;
   }
Value *FortifiedLibCallSimplifier::optimizeStrpCpyChk(CallInst *CI,
   return Ret;
 }
 
 Value *FortifiedLibCallSimplifier::optimizeStrpNCpyChk(CallInst *CI,
                                                        IRBuilder<> &B,
                                                        LibFunc::Func Func) {
   Function *Callee = CI->getCalledFunction();
   StringRef Name = Callee->getName();
-
-  if (!checkStringCopyLibFuncSignature(Callee, Func))
-    return nullptr;
   if (isFortifiedCallFoldable(CI, 3, 2, false)) {
     Value *Ret = emitStrNCpy(CI->getArgOperand(0), CI->getArgOperand(1),
                              CI->getArgOperand(2), B, TLI, Name.substr(2, 7));
     return Ret;
   }
   return nullptr;
 }
 
 Value *FortifiedLibCallSimplifier::optimizeCall(CallInst *CI) {
   // FIXME: We shouldn't be changing "nobuiltin" or TLI unavailable calls here.
   // Some clang users checked for _chk libcall availability using:
   //   __has_builtin(__builtin___memcpy_chk)
   // When compiling with -fno-builtin, this is always true.
   // When passing -ffreestanding/-mkernel, which both imply -fno-builtin, we
   // end up with fortified libcalls, which isn't acceptable in a freestanding
   // environment which only provides their non-fortified counterparts.
   //
   // Until we change clang and/or teach external users to check for availability
   // differently, disregard the "nobuiltin" attribute and TLI::has.
   //
   // PR23093.
 
   LibFunc::Func Func;
   Function *Callee = CI->getCalledFunction();
-  StringRef FuncName = Callee->getName();
 
   SmallVector<OperandBundleDef, 2> OpBundles;
   CI->getOperandBundlesAsDefs(OpBundles);
   IRBuilder<> Builder(CI, /*FPMathTag=*/nullptr, OpBundles);
   bool isCallingConvC = CI->getCallingConv() == llvm::CallingConv::C;
 
-  // First, check that this is a known library functions.
-  if (!TLI->getLibFunc(FuncName, Func))
+  // First, check that this is a known library functions and that the prototype
+  // is correct.
+  if (!TLI->getLibFunc(*Callee, Func))
     return nullptr;
 
   // We never change the calling convention.
   if (!ignoreCallingConv(Func) && !isCallingConvC)
     return nullptr;
 
   switch (Func) {
   case LibFunc::memcpy_chk: