pointer first.
This most important effect of this is that accesses to that
field don't need to be dynamically offsetted past an arbitrary
number of value witnesses, which is pretty nice for the
generic value witnesses.
Swift SVN r16243
This is easier to emit optimal code for on our target platforms, and is more likely to find a contiguous range of spare bits to place the tag in.
Swift SVN r12435
Export EnumImplStrategy from the GenEnum.h header, and add some accessors that LLDB or other interested parties can use to work out how an enum is laid out:
- getElementsWithPayload() and getElementsWithNoPayload(), to pick out the cases that were laid out as nonempty and empty (including those that are considered no-payload due to empty type optimization);
- getBitPatternForNoPayloadElement() to return the unique bit pattern representing a no-payload case; and
- getTagBitsForPayloads() to return the bitmask of the discriminator tag for payload cases.
Swift SVN r12269
