For the varargs functions that used the Type field to validate their parameters, now a hidden additional argument is passed which contains a byte array with the type info for the current call's arguments. Since this is static per call location it can be better prepared once when the code is being compiled instead of being put in a runtime created array for each invocation. Everything else uses the per-function instance of the same data.
The only thing that still needed the type field with a VMValue is the defaults array, so this uses a different struct type now to store its data.
Currently used for loading parameters into registers.
For checking parameters of native functions some more work is needed to get the info to the function. Currently it doesn't receive the function descriptor.
src/scripting/vm/jit_call.cpp:164:38: warning: offset of on non-standard-layout type 'VMScriptFunction' [-Winvalid-offsetof]
src/scripting/vm/jit_load.cpp:87:50: warning: offset of on non-standard-layout type 'DObject' [-Winvalid-offsetof]
src/scripting/vm/jit_load.cpp:96:50: warning: offset of on non-standard-layout type 'DObject' [-Winvalid-offsetof]
src/scripting/vm/jit_load.cpp:257:53: warning: offset of on non-standard-layout type 'DObject' [-Winvalid-offsetof]
The amount of support code for this minor optimization was quite large and this stood in the way of streamlining the VM's calling convention, so it was preferable to remove it before moving on.
With a proper count value available this can be done properly. The only relevant targets are the jumps immediately succeeding the IJMP instructions, nothing else.
This isn't used for the 3 action function calls because it requires an array allocation which would be a bit too costly for something as frequently called as action functions.
They will need a different approach.
The instruction one free instruction byte so it's now using that to extend its argument's register range to 65535.
For param this is needed because it passes strings by reference and creating an implicit temporary copy for string constants does not work here.
