1 //===-- InstrinsicInst.cpp - Intrinsic Instruction Wrappers ---------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This file implements methods that make it really easy to deal with intrinsic 11 // functions. 12 // 13 // All intrinsic function calls are instances of the call instruction, so these 14 // are all subclasses of the CallInst class. Note that none of these classes 15 // has state or virtual methods, which is an important part of this gross/neat 16 // hack working. 17 // 18 // In some cases, arguments to intrinsics need to be generic and are defined as 19 // type pointer to empty struct { }*. To access the real item of interest the 20 // cast instruction needs to be stripped away. 21 // 22 //===----------------------------------------------------------------------===// 23 24 #include "llvm/IR/IntrinsicInst.h" 25 #include "llvm/IR/Constants.h" 26 #include "llvm/IR/GlobalVariable.h" 27 #include "llvm/IR/Metadata.h" 28 #include "llvm/Support/raw_ostream.h" 29 using namespace llvm; 30 31 //===----------------------------------------------------------------------===// 32 /// DbgInfoIntrinsic - This is the common base class for debug info intrinsics 33 /// 34 35 Value *DbgInfoIntrinsic::getVariableLocation(bool AllowNullOp) const { 36 Value *Op = getArgOperand(0); 37 if (AllowNullOp && !Op) 38 return nullptr; 39 40 auto *MD = cast<MetadataAsValue>(Op)->getMetadata(); 41 if (auto *V = dyn_cast<ValueAsMetadata>(MD)) 42 return V->getValue(); 43 44 // When the value goes to null, it gets replaced by an empty MDNode. 45 assert(!cast<MDNode>(MD)->getNumOperands() && "Expected an empty MDNode"); 46 return nullptr; 47 } 48 49 int llvm::Intrinsic::lookupLLVMIntrinsicByName(ArrayRef<const char *> NameTable, 50 StringRef Name) { 51 assert(Name.startswith("llvm.")); 52 53 // Do successive binary searches of the dotted name components. For 54 // "llvm.gc.experimental.statepoint.p1i8.p1i32", we will find the range of 55 // intrinsics starting with "llvm.gc", then "llvm.gc.experimental", then 56 // "llvm.gc.experimental.statepoint", and then we will stop as the range is 57 // size 1. During the search, we can skip the prefix that we already know is 58 // identical. By using strncmp we consider names with differing suffixes to 59 // be part of the equal range. 60 size_t CmpStart = 0; 61 size_t CmpEnd = 4; // Skip the "llvm" component. 62 const char *const *Low = NameTable.begin(); 63 const char *const *High = NameTable.end(); 64 const char *const *LastLow = Low; 65 while (CmpEnd < Name.size() && High - Low > 0) { 66 CmpStart = CmpEnd; 67 CmpEnd = Name.find('.', CmpStart + 1); 68 CmpEnd = CmpEnd == StringRef::npos ? Name.size() : CmpEnd; 69 auto Cmp = [CmpStart, CmpEnd](const char *LHS, const char *RHS) { 70 return strncmp(LHS + CmpStart, RHS + CmpStart, CmpEnd - CmpStart) < 0; 71 }; 72 LastLow = Low; 73 std::tie(Low, High) = std::equal_range(Low, High, Name.data(), Cmp); 74 } 75 if (High - Low > 0) 76 LastLow = Low; 77 78 if (LastLow == NameTable.end()) 79 return -1; 80 StringRef NameFound = *LastLow; 81 if (Name == NameFound || 82 (Name.startswith(NameFound) && Name[NameFound.size()] == '.')) 83 return LastLow - NameTable.begin(); 84 return -1; 85 } 86
