Every time an event happens in the library that the user should be
aware of, the callback will be invoked.
The existing diagnostic mechanism is hijacked internally by a
callback that creates an diagnostic object each time an event
happens.
Use libspirv::CapabilitySet instead of a 64-bit mask.
Remove dead function spvOpcodeRequiresCapability and its tests.
The JSON grammar parser is simplified since it just writes the
list of capabilities as a braced list, and takes advantage of
the CapabilitySet intializer-list constructor.
* Creates an ID class which manages definition and use of IDs
* Moved tracking code from validate.cpp to validate_id.cpp
* Rename and combine SsaPass and ProcessIds into IdPass
* Remove module dependency in Function
For dominance calculations we use an "augmented" CFG
where we always add a pseudo-entry node that is the predecessor
in the augmented CFG to any nodes that have no predecessors in the
regular CFG. Similarly, we add a pseudo-exit node that is the
predecessor in the augmented CFG that is a successor to any
node that has no successors in the regular CFG.
Pseudo entry and exit blocks live in the Function object.
Fixes a subtle problem where we were implicitly creating
the block_details for the pseudo-exit node since it didn't
appear in the idoms map, and yet we referenced it. In such a case the
contents of the block details could be garbage, or zero-initialized.
That sometimes caused incorrect calculation of immediate dominators
and post-dominators. For example, on a debug build where the details
could be zero-initialized, the dominator of an unreachable block would
be given as the pseudo-exit node. Bizarre.
Also, enforce the rule that you must have an OpFunctionEnd to close off
the last function.
