[PATCH] D22974: pdbdump: Dump Free Page Map contents.

[Rui Ueyama via llvm-commits]

ruiu added inline comments.

================
Comment at: lib/DebugInfo/PDB/Raw/PDBFile.cpp:52
@@ +51,3 @@
+// because otherwise the result would be large, as most pages are unused.)
+Expected<std::vector<uint32_t>> PDBFile::getUsedBlockList() const {
+  uint64_t Offset = ContainerLayout.SB->FreeBlockMapBlock * getBlockSize();
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zturner wrote:
> ruiu wrote:
> > zturner wrote:
> > > How about adding another field to the `MsfLayout` class called `FreePageMap`?  You will need to set the value in `MsfBuilder::build()` before returning, and you will also need to set it in `PDBFile::parseFileHeaders()`.
> > > 
> > > This way you wouldn't need to return an `Expected<std::vector<uint32_t>>` but rather a `const BitVector&`, and the reading / writing code would share the same common structures.
> > What is a bit annoying is that BitVector doesn't provide a way to map itself onto an existing bitmap, so I need to examine each bit and flip a bit in a BitVector. But, because the number of bits we have here is small anyways, it is probably okay to copy bit by bit. I'll try to add BitVector to MsfLayout.
> It seems like we could just add a new constructor to the `BitVector` class like this:
> 
> `BitVector(BitWord *Buffer, uint32_t NumBits)`;
BitWord is an internal thing of BitVector, so it probably should be `uint8_t *` and NumBits, or ArrayRef<uint8_t>. I'll try to see if I can add a new constructor.


https://reviews.llvm.org/D22974