[TLI] Unify LibFunc signature checking. NFCI.

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

Differential Revision: http://reviews.llvm.org/D19469

llvm-svn: 267758

1 files changed, 531 insertions, 0 deletions

diff --git a/llvm/lib/Analysis/TargetLibraryInfo.cpp b/llvm/lib/Analysis/TargetLibraryInfo.cpp
index 2d34ac2bd5c..36f83adeaa1 100644
--- a/llvm/lib/Analysis/TargetLibraryInfo.cpp
+++ b/llvm/lib/Analysis/TargetLibraryInfo.cpp
@@ -479,6 +479,537 @@ bool TargetLibraryInfoImpl::getLibFunc(StringRef funcName,
   return false;
 }
 
+bool TargetLibraryInfoImpl::isValidProtoForLibFunc(const FunctionType &FTy,
+                                                   LibFunc::Func F,
+                                                   const DataLayout *DL) const {
+  LLVMContext &Ctx = FTy.getContext();
+  Type *PCharTy = Type::getInt8PtrTy(Ctx);
+  Type *SizeTTy = DL ? DL->getIntPtrType(Ctx, /*AS=*/0) : nullptr;
+  auto IsSizeTTy = [SizeTTy](Type *Ty) {
+    return SizeTTy ? Ty == SizeTTy : 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 (!IsSizeTTy(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 (!IsSizeTTy(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 (!IsSizeTTy(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() &&
+            IsSizeTTy(FTy.getParamType(2)));
+
+  case LibFunc::memset_chk:
+    --NumParams;
+    if (!IsSizeTTy(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() &&
+            IsSizeTTy(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 {
+  const DataLayout *DL =
+      FDecl.getParent() ? &FDecl.getParent()->getDataLayout() : nullptr;
+  return getLibFunc(FDecl.getName(), F) &&
+         isValidProtoForLibFunc(*FDecl.getFunctionType(), F, DL);
+}
+
 void TargetLibraryInfoImpl::disableAllFunctions() {
   memset(AvailableArray, 0, sizeof(AvailableArray));
 }