| //===- LibCallSemantics.cpp - Describe library semantics ------------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements interfaces that can be used to describe language |
| // specific runtime library interfaces (e.g. libc, libm, etc) to LLVM |
| // optimizers. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "llvm/Analysis/LibCallSemantics.h" |
| #include "llvm/ADT/StringMap.h" |
| #include "llvm/ADT/StringSwitch.h" |
| #include "llvm/IR/Function.h" |
| using namespace llvm; |
| |
| /// This impl pointer in ~LibCallInfo is actually a StringMap. This |
| /// helper does the cast. |
| static StringMap<const LibCallFunctionInfo*> *getMap(void *Ptr) { |
| return static_cast<StringMap<const LibCallFunctionInfo*> *>(Ptr); |
| } |
| |
| LibCallInfo::~LibCallInfo() { |
| delete getMap(Impl); |
| } |
| |
| const LibCallLocationInfo &LibCallInfo::getLocationInfo(unsigned LocID) const { |
| // Get location info on the first call. |
| if (NumLocations == 0) |
| NumLocations = getLocationInfo(Locations); |
| |
| assert(LocID < NumLocations && "Invalid location ID!"); |
| return Locations[LocID]; |
| } |
| |
| |
| /// Return the LibCallFunctionInfo object corresponding to |
| /// the specified function if we have it. If not, return null. |
| const LibCallFunctionInfo * |
| LibCallInfo::getFunctionInfo(const Function *F) const { |
| StringMap<const LibCallFunctionInfo*> *Map = getMap(Impl); |
| |
| /// If this is the first time we are querying for this info, lazily construct |
| /// the StringMap to index it. |
| if (!Map) { |
| Impl = Map = new StringMap<const LibCallFunctionInfo*>(); |
| |
| const LibCallFunctionInfo *Array = getFunctionInfoArray(); |
| if (!Array) return nullptr; |
| |
| // We now have the array of entries. Populate the StringMap. |
| for (unsigned i = 0; Array[i].Name; ++i) |
| (*Map)[Array[i].Name] = Array+i; |
| } |
| |
| // Look up this function in the string map. |
| return Map->lookup(F->getName()); |
| } |
| |
| /// See if the given exception handling personality function is one that we |
| /// understand. If so, return a description of it; otherwise return Unknown. |
| EHPersonality llvm::classifyEHPersonality(const Value *Pers) { |
| const Function *F = dyn_cast<Function>(Pers->stripPointerCasts()); |
| if (!F) |
| return EHPersonality::Unknown; |
| return StringSwitch<EHPersonality>(F->getName()) |
| .Case("__gnat_eh_personality", EHPersonality::GNU_Ada) |
| .Case("__gxx_personality_v0", EHPersonality::GNU_CXX) |
| .Case("__gcc_personality_v0", EHPersonality::GNU_C) |
| .Case("__objc_personality_v0", EHPersonality::GNU_ObjC) |
| .Case("_except_handler3", EHPersonality::MSVC_X86SEH) |
| .Case("_except_handler4", EHPersonality::MSVC_X86SEH) |
| .Case("__C_specific_handler", EHPersonality::MSVC_Win64SEH) |
| .Case("__CxxFrameHandler3", EHPersonality::MSVC_CXX) |
| .Default(EHPersonality::Unknown); |
| } |
| |
| bool llvm::canSimplifyInvokeNoUnwind(const Function *F) { |
| EHPersonality Personality = classifyEHPersonality(F->getPersonalityFn()); |
| // We can't simplify any invokes to nounwind functions if the personality |
| // function wants to catch asynch exceptions. The nounwind attribute only |
| // implies that the function does not throw synchronous exceptions. |
| return !isAsynchronousEHPersonality(Personality); |
| } |