There is no polymorphism here, and StreamRef already contains a
StreamInterface pointer. Dropping the base class makes StreamRef more
transparent to the compiler, for example it can find unused variables.
llvm-svn: 275013
Somehow all the functionality to write PDB files got removed,
probably accidentally when uploading the patch perhaps the wrong
one got uploaded. This re-adds all the code, as well as the
corresponding test.
llvm-svn: 274248
This reverts commit 879139e1c6577b09df52de56a6bab856a19ed185.
This was committed accidentally when I blindly typed git svn
dcommit instead of the command to generate a patch.
llvm-svn: 272693
This adds method and tests for writing to a PDB stream. With
this, even a PDB stream which is discontiguous can be treated
as a sequential stream of bytes for the purposes of writing.
Reviewed By: ruiu
Differential Revision: http://reviews.llvm.org/D21157
llvm-svn: 272369
This first pass only splits apart the records and dumps the line
info kinds and binary data. Subsequent patches will parse out
the binary data into more useful information and dump it in
detail.
llvm-svn: 271576
StreamRef was designed to be a thin wrapper over an abstract
stream interface that could itself be treated the same as any
other stream interface. For this reason, it inherited publicly
from StreamInterface, and stored a StreamInterface* internally.
But StreamRef was also designed to be lightweight and easily
copyable, similar to ArrayRef. This led to two misuses of
the classes.
1) When creating a StreamRef A from another StreamRef B, it was
possible to end up with A storing a pointer to B, even when
B was a temporary object, leading to use after free.
2) The above situation could be repeated ad nauseum, so that
A stores a pointer to B, which itself stores a pointer to
another StreamRef C, and so on and so on, creating an
unnecessarily level of nesting depth.
This patch removes the public inheritance relationship between
StreamRef and StreamInterface, making it so that we can never
accidentally convert a StreamRef to a StreamInterface.
llvm-svn: 271570
We only considered the length of the operation and the length of the
StreamRef without considered what it meant for the offset to be at a
non-zero position.
llvm-svn: 271496
This converts remaining uses of ByteStream, which was still
left in the symbol stream and type stream, to using the new
StreamInterface zero-copy classes.
RecordIterator is finally deleted, so this is the only way left
now. Additionally, more error checking is added when iterating
the various streams.
With this, the transition to zero copy pdb access is complete.
llvm-svn: 271101
PDBs can be extremely large. We're already mapping the entire
PDB into the process's address space, but to make matters worse
the blocks of the PDB are not arranged contiguously. So, when
we have something like an array or a string embedded into the
stream, we have to make a copy. Since it's convenient to use
traditional data structures to iterate and manipulate these
records, we need the memory to be contiguous.
As a result of this, we were using roughly twice as much memory
as the file size of the PDB, because every stream was copied
out and re-stitched together contiguously.
This patch addresses this by improving the MappedBlockStream
to allocate from a BumpPtrAllocator only when a read requires
a discontiguous read. Furthermore, it introduces some data
structures backed by a stream which can iterate over both
fixed and variable length records of a PDB. Since everything
is backed by a stream and not a buffer, we can read almost
everything from the PDB with zero copies.
Differential Revision: http://reviews.llvm.org/D20654
Reviewed By: ruiu
llvm-svn: 270951
