[llvm] r221794 - Return the number of read bytes in MemoryObject::readBytes.

[Jay Foad]

On 12 November 2014 17:11, Rafael Espindola <rafael.espindola at gmail.com> wrote:
> -int RawMemoryObject::readBytes(uint64_t address,
> -                               uint64_t size,
> -                               uint8_t *buf) const {
> -  if (!validAddress(address) || !validAddress(address + size - 1)) return -1;
> -  memcpy(buf, (uint8_t *)(uintptr_t)(address + FirstChar), size);
> -  return size;
> +uint64_t RawMemoryObject::readBytes(uint8_t *Buf, uint64_t Size,
> +                                    uint64_t Address) const {
> +  uint64_t BufferSize = LastChar - FirstChar;
> +  if (Address >= BufferSize)
> +    return 0;
> +
> +  uint64_t End = Address + Size;
> +  if (End > BufferSize)
> +    End = BufferSize;
> +
> +  Size = End - Address;
> +  assert(Size >= 0);

/home/admin/llvm-project/llvm/lib/Support/StreamingMemoryObject.cpp:63:18:
warning: comparison of unsigned expression >= 0 is always true
[-Wtype-limits]

> +  memcpy(Buf, (uint8_t *)(Address + FirstChar), Size);
> +  return Size;
>  }
>
>  const uint8_t *RawMemoryObject::getPointer(uint64_t address,
> @@ -91,12 +99,20 @@ uint64_t StreamingMemoryObject::getExten
>    return ObjectSize;
>  }
>
> -int StreamingMemoryObject::readBytes(uint64_t address,
> -                                     uint64_t size,
> -                                     uint8_t *buf) const {
> -  if (!fetchToPos(address + size - 1)) return -1;
> -  memcpy(buf, &Bytes[address + BytesSkipped], size);
> -  return 0;
> +uint64_t StreamingMemoryObject::readBytes(uint8_t *Buf, uint64_t Size,
> +                                          uint64_t Address) const {
> +  fetchToPos(Address + Size - 1);
> +  uint64_t BufferSize = Bytes.size() - BytesSkipped;
> +  if (Address >= BufferSize)
> +    return 0;
> +
> +  uint64_t End = Address + Size;
> +  if (End > BufferSize)
> +    End = BufferSize;
> +  Size = End - Address;
> +  assert(Size >= 0);

/home/admin/llvm-project/llvm/lib/Support/StreamingMemoryObject.cpp:100:18:
warning: comparison of unsigned expression >= 0 is always true
[-Wtype-limits]

Jay.