The previous API for forward declarations broke when more than one
definition was done. Forward references on instructions that are not
labels were only needed for phi nodes, so it has been replaced with a
deferred phi node instruction and a method to patch these after
everything has been defined.
These Vulkan 1.1 operations can be used in place of
`OpSubgroup{All,Any,AllEqual,Ballot}KHR`, among other things.
For `OpGroupNonUniformShuffleXor`, which was already implemented, turns
out the scope argument needs to be encoded not as an immediate, but as
an id that points to a constant integer.
Before this commit sirit generated a stream of tokens that would then be
inserted to the final SPIR-V binary. This design was carried from the
initial design of manually inserting opcodes into the code. Now that
all instructions but labels are inserted when their respective function
is called, the old design can be dropped in favor of generating a valid
stream of SPIR-V opcodes.
The API for variables is broken, but adopting the new one is trivial.
Instead of calling OpVariable and then adding a global or local
variable, OpVariable was removed and global or local variables are
generated when they are called.
Avoiding duplicates is now done with an std::unordered_set instead of
using a linear search jumping through vtables.
Enable cast warnings in gcc and clang and always treat warnings as
errors.
GetWordCount now returns std::size_t for simplicity and the word count
is asserted and casted in WordCount (now called CalculateTotalWords.
Silence warnings.
All instructions but OpVariable and OpLabel are automatically emitted.
These functions have to call AddLocalVariable/AddGlobalVariable or
AddLabel respectively.
