1 //===--- InterpStack.cpp - Stack implementation for the VM ------*- C++ -*-===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #include "InterpStack.h" 10 #include "Boolean.h" 11 #include "Floating.h" 12 #include "Integral.h" 13 #include <cassert> 14 #include <cstdlib> 15 16 using namespace clang; 17 using namespace clang::interp; 18 19 InterpStack::~InterpStack() { 20 clear(); 21 } 22 23 void InterpStack::clear() { 24 if (Chunk && Chunk->Next) 25 std::free(Chunk->Next); 26 if (Chunk) 27 std::free(Chunk); 28 Chunk = nullptr; 29 StackSize = 0; 30 #ifndef NDEBUG 31 ItemTypes.clear(); 32 #endif 33 } 34 35 void *InterpStack::grow(size_t Size) { 36 assert(Size < ChunkSize - sizeof(StackChunk) && "Object too large"); 37 38 if (!Chunk || sizeof(StackChunk) + Chunk->size() + Size > ChunkSize) { 39 if (Chunk && Chunk->Next) { 40 Chunk = Chunk->Next; 41 } else { 42 StackChunk *Next = new (std::malloc(ChunkSize)) StackChunk(Chunk); 43 if (Chunk) 44 Chunk->Next = Next; 45 Chunk = Next; 46 } 47 } 48 49 auto *Object = reinterpret_cast<void *>(Chunk->End); 50 Chunk->End += Size; 51 StackSize += Size; 52 return Object; 53 } 54 55 void *InterpStack::peekData(size_t Size) const { 56 assert(Chunk && "Stack is empty!"); 57 58 StackChunk *Ptr = Chunk; 59 while (Size > Ptr->size()) { 60 Size -= Ptr->size(); 61 Ptr = Ptr->Prev; 62 assert(Ptr && "Offset too large"); 63 } 64 65 return reinterpret_cast<void *>(Ptr->End - Size); 66 } 67 68 void InterpStack::shrink(size_t Size) { 69 assert(Chunk && "Chunk is empty!"); 70 71 while (Size > Chunk->size()) { 72 Size -= Chunk->size(); 73 if (Chunk->Next) { 74 std::free(Chunk->Next); 75 Chunk->Next = nullptr; 76 } 77 Chunk->End = Chunk->start(); 78 Chunk = Chunk->Prev; 79 assert(Chunk && "Offset too large"); 80 } 81 82 Chunk->End -= Size; 83 StackSize -= Size; 84 } 85 86 void InterpStack::dump() const { 87 #ifndef NDEBUG 88 llvm::errs() << "Items: " << ItemTypes.size() << ". Size: " << size() << "\n"; 89 if (ItemTypes.empty()) 90 return; 91 92 size_t Index = 0; 93 size_t Offset = align(primSize(ItemTypes[0])); 94 for (PrimType Ty : ItemTypes) { 95 llvm::errs() << Index << "/" << Offset << ": "; 96 TYPE_SWITCH(Ty, { 97 const T &V = peek<T>(Offset); 98 llvm::errs() << V; 99 }); 100 llvm::errs() << "\n"; 101 Offset += align(primSize(Ty)); 102 ++Index; 103 } 104 #endif 105 } 106