If this is a problem for anyone (shared_ptr is two pointers in size,
whereas IntrusiveRefCntPtr is 1 - and the ref count control block that
make_shared adds is probably larger than the one int in RefCountedBase)
I'd prefer to address this by adding a lower-overhead version of
shared_ptr (possibly refactoring IntrusiveRefCntPtr into such a thing)
to avoid the intrusiveness - this allows memory ownership to remain
orthogonal to types and at least to me, seems to make code easier to
understand (since no implicit ownership acquisition can happen).
This recommits 291006, reverted in r291007.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291016 91177308-0d34-0410-b5e6-96231b3b80d8
Breaks Clang's use of bitcode. Reverting until I have a fix to go with
it there.
This reverts commit r291006.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291007 91177308-0d34-0410-b5e6-96231b3b80d8
If this is a problem for anyone (shared_ptr is two pointers in size,
whereas IntrusiveRefCntPtr is 1 - and the ref count control block that
make_shared adds is probably larger than the one int in RefCountedBase)
I'd prefer to address this by adding a lower-overhead version of
shared_ptr (possibly refactoring IntrusiveRefCntPtr into such a thing)
to avoid the intrusiveness - this allows memory ownership to remain
orthogonal to types and at least to me, seems to make code easier to
understand (since no implicit ownership acquisition can happen).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291006 91177308-0d34-0410-b5e6-96231b3b80d8
As proposed on llvm-dev:
http://lists.llvm.org/pipermail/llvm-dev/2016-October/106595.html
This change also fixes an API oddity where BitstreamCursor::Read() would
return zero for the first read past the end of the bitstream, but would
report_fatal_error for subsequent reads. Now we always report_fatal_error
for all reads past the end. Updated clients to check for the end of the
bitstream before reading from it.
I also needed to add padding to the invalid bitcode tests in
test/Bitcode/. This is because the streaming interface was not checking that
the file size is a multiple of 4.
Differential Revision: https://reviews.llvm.org/D26219
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@285773 91177308-0d34-0410-b5e6-96231b3b80d8
Explicitly check that artificial byte limit is rounded correctly by
exposing BitstreamReader::Size through a new accessor, getSizeIfKnown.
The original code for rounding (from r264547) wasn't obviously correct,
and even though r264623 cleaned it up (by calling llvm::alignTo) I think
it's worth testing.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@264650 91177308-0d34-0410-b5e6-96231b3b80d8
The implementation is fairly obvious. This is preparation for using
some blobs in bitcode.
For clarity (and perhaps future-proofing?), I moved the call to
JumpToBit in BitstreamCursor::readRecord ahead of calling
MemoryObject::getPointer, since JumpToBit can theoretically (a) read
bytes, which (b) invalidates the blob pointer.
This isn't strictly necessary the two memory objects we have:
- The return of RawMemoryObject::getPointer is valid until the memory
object is destroyed.
- StreamingMemoryObject::getPointer is valid until the next chunk is
read from the stream. Since the JumpToBit call is only going ahead
to a word boundary, we'll never load another chunk.
However, reordering makes it clear by inspection that the blob returned
by BitstreamCursor::readRecord will be valid.
I added some tests for StreamingMemoryObject::getPointer and
BitstreamCursor::readRecord.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@264549 91177308-0d34-0410-b5e6-96231b3b80d8
Allow users of SimpleBitstreamCursor to limit the number of bytes
available to the cursor. This is preparation for instantiating a cursor
that isn't allowed to load more bytes from a StreamingMemoryObject (just
move around the ones already-loaded).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@264547 91177308-0d34-0410-b5e6-96231b3b80d8
Add API to SimpleBitstreamCursor to allow users to translate between
byte addresses and pointers.
- jumpToPointer: move the bit position to a particular pointer.
- getPointerToByte: get the pointer for a particular byte.
- getPointerToBit: get the pointer for the byte of the current bit.
- getCurrentByteNo: convenience function for assertions and tests.
Mainly adds unit tests (getPointerToBit/Byte already has a use), but
also preparation for eventually using jumpToPointer.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@264546 91177308-0d34-0410-b5e6-96231b3b80d8
This avoids an issue where AtEndOfStream mistakenly returns true at the /start/ of
a stream.
(In the rare case that the size is known and actually 0, the slow path will still
handle it correctly.)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221840 91177308-0d34-0410-b5e6-96231b3b80d8
