cling/lib/Interpreter/StoredValueRef.cpp

//------------------------------------------------------------------------------
// CLING - the C++ LLVM-based InterpreterG :)
// version: $Id: ValuePrinter.cpp 46307 2012-10-04 06:53:23Z axel $
// author:  Axel Naumann <axel@cern.ch>
//------------------------------------------------------------------------------

#include "cling/Interpreter/StoredValueRef.h"
#include "clang/AST/ASTContext.h"

using namespace cling;
using namespace clang;
using namespace llvm;

StoredValueRef::StoredValue::StoredValue(const ASTContext& ctx, QualType t):
m_Mem(0) {
  type = t;
  if (!(t->isIntegralOrEnumerationType()
        || t->isRealFloatingType()
        || t->hasPointerRepresentation())) {
    const uint64_t size = (uint64_t)getAllocSizeInBytes(ctx);
    if (size > sizeof(m_Buf))
      m_Mem = new char[size];
    else m_Mem = m_Buf;
    value = llvm::PTOGV(m_Mem);
  };
}

StoredValueRef::StoredValue::~StoredValue() {
  if (m_Mem != m_Buf)
    delete [] m_Mem;
}

int64_t StoredValueRef::StoredValue::getAllocSizeInBytes(
                                                  const ASTContext& ctx) const {
  return ctx.getTypeSizeInChars(type).getQuantity();
}




StoredValueRef StoredValueRef::allocate(const ASTContext& ctx, QualType t) {
  return new StoredValue(ctx, t);
}

StoredValueRef StoredValueRef::bitwiseCopy(const ASTContext& ctx,
                                           const Value& value) {
  StoredValue* SValue = new StoredValue(ctx, value.type);
  if (SValue->m_Mem) {
    const char* src = (const char*)value.value.PointerVal;
    // It's not a pointer. LLVM stores a char[5] (i.e. 5 x i8) as an i40,
    // so use that instead. We don't keep it as an int; instead, we "allocate"
    // it as a "proper" char[5] in the m_Mem. "Allocate" because it uses the
    // m_Buf, so no actual allocation happens.
    uint64_t IntVal = value.value.IntVal.getSExtValue();
    if (!src) src = (const char*)&IntVal;
    memcpy(SValue->m_Mem, src,
           SValue->getAllocSizeInBytes(ctx));
  } else {
    SValue->value = value.value;
  }
  return SValue;
}