//===- InferFunctionAttrs.cpp - Infer implicit function attributes --------===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// #include "llvm/Transforms/IPO/InferFunctionAttrs.h" #include "llvm/ADT/Statistic.h" #include "llvm/Analysis/TargetLibraryInfo.h" #include "llvm/Analysis/MemoryBuiltins.h" #include "llvm/IR/Function.h" #include "llvm/IR/LLVMContext.h" #include "llvm/IR/Module.h" #include "llvm/Support/Debug.h" #include "llvm/Support/raw_ostream.h" using namespace llvm; #define DEBUG_TYPE "inferattrs" STATISTIC(NumReadNone, "Number of functions inferred as readnone"); STATISTIC(NumReadOnly, "Number of functions inferred as readonly"); STATISTIC(NumArgMemOnly, "Number of functions inferred as argmemonly"); STATISTIC(NumNoUnwind, "Number of functions inferred as nounwind"); STATISTIC(NumNoCapture, "Number of arguments inferred as nocapture"); STATISTIC(NumReadOnlyArg, "Number of arguments inferred as readonly"); STATISTIC(NumNoAlias, "Number of function returns inferred as noalias"); STATISTIC(NumNonNull, "Number of function returns inferred as nonnull returns"); static bool setDoesNotAccessMemory(Function &F) { if (F.doesNotAccessMemory()) return false; F.setDoesNotAccessMemory(); ++NumReadNone; return true; } static bool setOnlyReadsMemory(Function &F) { if (F.onlyReadsMemory()) return false; F.setOnlyReadsMemory(); ++NumReadOnly; return true; } static bool setOnlyAccessesArgMemory(Function &F) { if (F.onlyAccessesArgMemory()) return false; F.setOnlyAccessesArgMemory (); ++NumArgMemOnly; return true; } static bool setDoesNotThrow(Function &F) { if (F.doesNotThrow()) return false; F.setDoesNotThrow(); ++NumNoUnwind; return true; } static bool setDoesNotCapture(Function &F, unsigned n) { if (F.doesNotCapture(n)) return false; F.setDoesNotCapture(n); ++NumNoCapture; return true; } static bool setOnlyReadsMemory(Function &F, unsigned n) { if (F.onlyReadsMemory(n)) return false; F.setOnlyReadsMemory(n); ++NumReadOnlyArg; return true; } static bool setDoesNotAlias(Function &F, unsigned n) { if (F.doesNotAlias(n)) return false; F.setDoesNotAlias(n); ++NumNoAlias; return true; } static bool setNonNull(Function &F, unsigned n) { assert((n != AttributeSet::ReturnIndex || F.getReturnType()->isPointerTy()) && "nonnull applies only to pointers"); if (F.getAttributes().hasAttribute(n, Attribute::NonNull)) return false; F.addAttribute(n, Attribute::NonNull); ++NumNonNull; return true; } /// Analyze the name and prototype of the given function and set any applicable /// 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; LibFunc::Func TheLibFunc; if (!(TLI.getLibFunc(F, TheLibFunc) && TLI.has(TheLibFunc))) return false; bool Changed = false; switch (TheLibFunc) { case LibFunc::strlen: Changed |= setOnlyReadsMemory(F); Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); return Changed; case LibFunc::strchr: case LibFunc::strrchr: 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: 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: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 2); Changed |= setOnlyReadsMemory(F, 2); return Changed; case LibFunc::strxfrm: 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: // Changed |= setOnlyReadsMemory(F); Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setDoesNotCapture(F, 2); return Changed; case LibFunc::strstr: case LibFunc::strpbrk: Changed |= setOnlyReadsMemory(F); Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 2); return Changed; case LibFunc::strtok: case LibFunc::strtok_r: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 2); Changed |= setOnlyReadsMemory(F, 2); return Changed; case LibFunc::scanf: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setOnlyReadsMemory(F, 1); return Changed; case LibFunc::setbuf: case LibFunc::setvbuf: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); return Changed; case LibFunc::strdup: case LibFunc::strndup: Changed |= setDoesNotThrow(F); Changed |= setDoesNotAlias(F, 0); Changed |= setDoesNotCapture(F, 1); Changed |= setOnlyReadsMemory(F, 1); return Changed; case LibFunc::stat: case LibFunc::statvfs: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setDoesNotCapture(F, 2); Changed |= setOnlyReadsMemory(F, 1); return Changed; case LibFunc::sscanf: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setDoesNotCapture(F, 2); Changed |= setOnlyReadsMemory(F, 1); Changed |= setOnlyReadsMemory(F, 2); return Changed; case LibFunc::sprintf: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setDoesNotCapture(F, 2); Changed |= setOnlyReadsMemory(F, 2); return Changed; case LibFunc::snprintf: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setDoesNotCapture(F, 3); Changed |= setOnlyReadsMemory(F, 3); return Changed; case LibFunc::setitimer: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 2); Changed |= setDoesNotCapture(F, 3); Changed |= setOnlyReadsMemory(F, 2); return Changed; case LibFunc::system: // May throw; "system" is a valid pthread cancellation point. Changed |= setDoesNotCapture(F, 1); Changed |= setOnlyReadsMemory(F, 1); return Changed; case LibFunc::malloc: Changed |= setDoesNotThrow(F); Changed |= setDoesNotAlias(F, 0); return Changed; case LibFunc::memcmp: Changed |= setOnlyReadsMemory(F); Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setDoesNotCapture(F, 2); return Changed; case LibFunc::memchr: case LibFunc::memrchr: Changed |= setOnlyReadsMemory(F); Changed |= setDoesNotThrow(F); return Changed; case LibFunc::modf: case LibFunc::modff: case LibFunc::modfl: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 2); return Changed; case LibFunc::memcpy: case LibFunc::memccpy: case LibFunc::memmove: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 2); Changed |= setOnlyReadsMemory(F, 2); return Changed; case LibFunc::memalign: Changed |= setDoesNotAlias(F, 0); return Changed; case LibFunc::mkdir: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setOnlyReadsMemory(F, 1); return Changed; case LibFunc::mktime: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); return Changed; case LibFunc::realloc: Changed |= setDoesNotThrow(F); Changed |= setDoesNotAlias(F, 0); Changed |= setDoesNotCapture(F, 1); return Changed; case LibFunc::read: // May throw; "read" is a valid pthread cancellation point. Changed |= setDoesNotCapture(F, 2); return Changed; case LibFunc::rewind: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); return Changed; case LibFunc::rmdir: case LibFunc::remove: case LibFunc::realpath: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setOnlyReadsMemory(F, 1); return Changed; case LibFunc::rename: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setDoesNotCapture(F, 2); Changed |= setOnlyReadsMemory(F, 1); Changed |= setOnlyReadsMemory(F, 2); return Changed; case LibFunc::readlink: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setDoesNotCapture(F, 2); Changed |= setOnlyReadsMemory(F, 1); return Changed; case LibFunc::write: // May throw; "write" is a valid pthread cancellation point. Changed |= setDoesNotCapture(F, 2); Changed |= setOnlyReadsMemory(F, 2); return Changed; case LibFunc::bcopy: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setDoesNotCapture(F, 2); Changed |= setOnlyReadsMemory(F, 1); return Changed; case LibFunc::bcmp: Changed |= setDoesNotThrow(F); Changed |= setOnlyReadsMemory(F); Changed |= setDoesNotCapture(F, 1); Changed |= setDoesNotCapture(F, 2); return Changed; case LibFunc::bzero: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); return Changed; case LibFunc::calloc: Changed |= setDoesNotThrow(F); Changed |= setDoesNotAlias(F, 0); return Changed; case LibFunc::chmod: case LibFunc::chown: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setOnlyReadsMemory(F, 1); return Changed; case LibFunc::ctermid: case LibFunc::clearerr: case LibFunc::closedir: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); return Changed; case LibFunc::atoi: case LibFunc::atol: case LibFunc::atof: case LibFunc::atoll: Changed |= setDoesNotThrow(F); Changed |= setOnlyReadsMemory(F); Changed |= setDoesNotCapture(F, 1); return Changed; case LibFunc::access: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setOnlyReadsMemory(F, 1); return Changed; case LibFunc::fopen: 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: 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: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); return Changed; case LibFunc::ferror: 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: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 2); return Changed; case LibFunc::fgets: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 3); return Changed; case LibFunc::fread: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setDoesNotCapture(F, 4); return Changed; case LibFunc::fwrite: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setDoesNotCapture(F, 4); return Changed; case LibFunc::fputs: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setDoesNotCapture(F, 2); Changed |= setOnlyReadsMemory(F, 1); return Changed; case LibFunc::fscanf: case LibFunc::fprintf: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setDoesNotCapture(F, 2); Changed |= setOnlyReadsMemory(F, 2); return Changed; case LibFunc::fgetpos: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setDoesNotCapture(F, 2); return Changed; case LibFunc::getc: case LibFunc::getlogin_r: case LibFunc::getc_unlocked: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); return Changed; case LibFunc::getenv: 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: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 2); return Changed; case LibFunc::getpwnam: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setOnlyReadsMemory(F, 1); return Changed; case LibFunc::ungetc: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 2); return Changed; case LibFunc::uname: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); return Changed; case LibFunc::unlink: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setOnlyReadsMemory(F, 1); return Changed; case LibFunc::unsetenv: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setOnlyReadsMemory(F, 1); return Changed; case LibFunc::utime: case LibFunc::utimes: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setDoesNotCapture(F, 2); Changed |= setOnlyReadsMemory(F, 1); Changed |= setOnlyReadsMemory(F, 2); return Changed; case LibFunc::putc: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 2); return Changed; case LibFunc::puts: case LibFunc::printf: case LibFunc::perror: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setOnlyReadsMemory(F, 1); return Changed; case LibFunc::pread: // May throw; "pread" is a valid pthread cancellation point. Changed |= setDoesNotCapture(F, 2); return Changed; case LibFunc::pwrite: // 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: 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: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); return Changed; case LibFunc::vscanf: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setOnlyReadsMemory(F, 1); return Changed; case LibFunc::vsscanf: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setDoesNotCapture(F, 2); Changed |= setOnlyReadsMemory(F, 1); Changed |= setOnlyReadsMemory(F, 2); return Changed; case LibFunc::vfscanf: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setDoesNotCapture(F, 2); Changed |= setOnlyReadsMemory(F, 2); return Changed; case LibFunc::valloc: Changed |= setDoesNotThrow(F); Changed |= setDoesNotAlias(F, 0); return Changed; case LibFunc::vprintf: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setOnlyReadsMemory(F, 1); return Changed; case LibFunc::vfprintf: case LibFunc::vsprintf: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setDoesNotCapture(F, 2); Changed |= setOnlyReadsMemory(F, 2); return Changed; case LibFunc::vsnprintf: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setDoesNotCapture(F, 3); Changed |= setOnlyReadsMemory(F, 3); return Changed; case LibFunc::open: // May throw; "open" is a valid pthread cancellation point. Changed |= setDoesNotCapture(F, 1); Changed |= setOnlyReadsMemory(F, 1); return Changed; case LibFunc::opendir: Changed |= setDoesNotThrow(F); Changed |= setDoesNotAlias(F, 0); Changed |= setDoesNotCapture(F, 1); Changed |= setOnlyReadsMemory(F, 1); return Changed; case LibFunc::tmpfile: Changed |= setDoesNotThrow(F); Changed |= setDoesNotAlias(F, 0); return Changed; case LibFunc::times: 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: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setDoesNotCapture(F, 2); Changed |= setOnlyReadsMemory(F, 1); return Changed; case LibFunc::lchown: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setOnlyReadsMemory(F, 1); return Changed; case LibFunc::qsort: // May throw; places call through function pointer. Changed |= setDoesNotCapture(F, 4); return Changed; case LibFunc::dunder_strdup: case LibFunc::dunder_strndup: Changed |= setDoesNotThrow(F); Changed |= setDoesNotAlias(F, 0); Changed |= setDoesNotCapture(F, 1); Changed |= setOnlyReadsMemory(F, 1); return Changed; case LibFunc::dunder_strtok_r: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 2); Changed |= setOnlyReadsMemory(F, 2); return Changed; case LibFunc::under_IO_getc: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); return Changed; case LibFunc::under_IO_putc: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 2); return Changed; case LibFunc::dunder_isoc99_scanf: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setOnlyReadsMemory(F, 1); return Changed; case LibFunc::stat64: case LibFunc::lstat64: case LibFunc::statvfs64: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setDoesNotCapture(F, 2); Changed |= setOnlyReadsMemory(F, 1); return Changed; case LibFunc::dunder_isoc99_sscanf: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); Changed |= setDoesNotCapture(F, 2); Changed |= setOnlyReadsMemory(F, 1); Changed |= setOnlyReadsMemory(F, 2); return Changed; case LibFunc::fopen64: 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: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 1); return Changed; case LibFunc::tmpfile64: Changed |= setDoesNotThrow(F); Changed |= setDoesNotAlias(F, 0); return Changed; case LibFunc::fstat64: case LibFunc::fstatvfs64: Changed |= setDoesNotThrow(F); Changed |= setDoesNotCapture(F, 2); return Changed; case LibFunc::open64: // May throw; "open" is a valid pthread cancellation point. Changed |= setDoesNotCapture(F, 1); Changed |= setOnlyReadsMemory(F, 1); return Changed; case LibFunc::gettimeofday: // 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) // 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: Changed |= setOnlyAccessesArgMemory(F); Changed |= setOnlyReadsMemory(F, 2); return Changed; // int __nvvm_reflect(const char *) case LibFunc::nvvm_reflect: 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; } } static bool inferAllPrototypeAttributes(Module &M, const TargetLibraryInfo &TLI) { bool Changed = false; for (Function &F : M.functions()) // We only infer things using the prototype if the definition isn't around // to analyze directly. if (F.isDeclaration()) Changed |= inferPrototypeAttributes(F, TLI); return Changed; } PreservedAnalyses InferFunctionAttrsPass::run(Module &M, AnalysisManager &AM) { auto &TLI = AM.getResult(M); if (!inferAllPrototypeAttributes(M, TLI)) // If we didn't infer anything, preserve all analyses. return PreservedAnalyses::all(); // Otherwise, we may have changed fundamental function attributes, so clear // out all the passes. return PreservedAnalyses::none(); } namespace { struct InferFunctionAttrsLegacyPass : public ModulePass { static char ID; // Pass identification, replacement for typeid InferFunctionAttrsLegacyPass() : ModulePass(ID) { initializeInferFunctionAttrsLegacyPassPass( *PassRegistry::getPassRegistry()); } void getAnalysisUsage(AnalysisUsage &AU) const override { AU.addRequired(); } bool runOnModule(Module &M) override { if (skipModule(M)) return false; auto &TLI = getAnalysis().getTLI(); return inferAllPrototypeAttributes(M, TLI); } }; } char InferFunctionAttrsLegacyPass::ID = 0; INITIALIZE_PASS_BEGIN(InferFunctionAttrsLegacyPass, "inferattrs", "Infer set function attributes", false, false) INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfoWrapperPass) INITIALIZE_PASS_END(InferFunctionAttrsLegacyPass, "inferattrs", "Infer set function attributes", false, false) Pass *llvm::createInferFunctionAttrsLegacyPass() { return new InferFunctionAttrsLegacyPass(); }