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Dynamic VLIW
Allows a dynamic number of instructions to be queued for simultaneous execution
All inputs within the same queue will be calculated before outputs
`mov R0, R1` and `mov R1, R0` put into the same queue will result in swapping R0 and R1
If any exception occurs during the execution of the queued instructions, all output will be discarded
If multiple exceptions would have theoretically occurred, which one is triggered is undefined
If outputs from multiple instructions overlap, which one is written to the overlapping area is undefined
If an exception would be generated by attempting to write one value there but not the other, the exception might not occur if the other value is what is written in the end
This includes indirect writes via instructions such as `jmp` and `push`
Current format ideas:
A)
effects:
uses space efficiently when using many repetitions of the same opcodes
allows reuse of immediate references
easier for the CPU to parse
requires all parameter lengths to be the same within the opcode
wastes space when few repetitions of the same opcode exists and immediate references are rarely reused
format:
num_opcodes
for each:
opcode
num_instructions
for each:
parameters
size_of_immediate_references
for each:
value
B)
effects:
allows variable length parameters
harder for the CPU to parse
format:
size_of_queue
for each instruction:
opcode
parameters
immediate references
C)
effects:
allows variable length parameters
allows reuse of immediate references
harder for the CPU to parse
larger if immediate references are not reused
format:
size_of_instructions
for each instruction:
opcode
parameters
size_of_immediate_references
for each:
value
A minimum of <n> instructions must be accepted by all CPUs
TODO: define n
Specific implementations may accept more, up to the maximum specifiable by the format
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