You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
79 lines
1.8 KiB
79 lines
1.8 KiB
//===--- InterpStack.cpp - Stack implementation for the VM ------*- C++ -*-===//
|
|
//
|
|
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
|
|
// See https://llvm.org/LICENSE.txt for license information.
|
|
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include <cassert>
|
|
#include <cstdlib>
|
|
#include "InterpStack.h"
|
|
|
|
using namespace clang;
|
|
using namespace clang::interp;
|
|
|
|
InterpStack::~InterpStack() {
|
|
clear();
|
|
}
|
|
|
|
void InterpStack::clear() {
|
|
if (Chunk && Chunk->Next)
|
|
free(Chunk->Next);
|
|
if (Chunk)
|
|
free(Chunk);
|
|
Chunk = nullptr;
|
|
StackSize = 0;
|
|
}
|
|
|
|
void *InterpStack::grow(size_t Size) {
|
|
assert(Size < ChunkSize - sizeof(StackChunk) && "Object too large");
|
|
|
|
if (!Chunk || sizeof(StackChunk) + Chunk->size() + Size > ChunkSize) {
|
|
if (Chunk && Chunk->Next) {
|
|
Chunk = Chunk->Next;
|
|
} else {
|
|
StackChunk *Next = new (malloc(ChunkSize)) StackChunk(Chunk);
|
|
if (Chunk)
|
|
Chunk->Next = Next;
|
|
Chunk = Next;
|
|
}
|
|
}
|
|
|
|
auto *Object = reinterpret_cast<void *>(Chunk->End);
|
|
Chunk->End += Size;
|
|
StackSize += Size;
|
|
return Object;
|
|
}
|
|
|
|
void *InterpStack::peek(size_t Size) {
|
|
assert(Chunk && "Stack is empty!");
|
|
|
|
StackChunk *Ptr = Chunk;
|
|
while (Size > Ptr->size()) {
|
|
Size -= Ptr->size();
|
|
Ptr = Ptr->Prev;
|
|
assert(Ptr && "Offset too large");
|
|
}
|
|
|
|
return reinterpret_cast<void *>(Ptr->End - Size);
|
|
}
|
|
|
|
void InterpStack::shrink(size_t Size) {
|
|
assert(Chunk && "Chunk is empty!");
|
|
|
|
while (Size > Chunk->size()) {
|
|
Size -= Chunk->size();
|
|
if (Chunk->Next) {
|
|
free(Chunk->Next);
|
|
Chunk->Next = nullptr;
|
|
}
|
|
Chunk->End = Chunk->start();
|
|
Chunk = Chunk->Prev;
|
|
assert(Chunk && "Offset too large");
|
|
}
|
|
|
|
Chunk->End -= Size;
|
|
StackSize -= Size;
|
|
}
|