Octoproc ISA

	A	B	C	D	E	F	G	H	I	J	K	L
1	21-23	18-20	15-17	12-14	9-11	6-8	3-5	0-2	Mnemonic	Usage	Description	Notes
2			imm	r0	rd		0	0	LOAD	load rd, imm(r0)	Loads data from memory into a register.	rd = *(r0 + imm)
3			imm	r1	r0		0	1	STORE	store r0, imm(r1)	Stores data from a register into memory.	Acts like load.
4			imm	r0	rd	0	0	2	ADD IMM	add rd, r0, imm	Adds a register and an immediate.
5			imm	r0	rd	1	0	2	SUB IMM	sub rd, r0, imm	Subtracts a register and an immediate.
6	0	0	1	r0	rd	2	0	2	OSR IMM	osr rd, r0	Performs an right octit shift on a register.	Immediate is set to 001 for forwards compatibility for when I get around to makin a barrel shifter in V2.
7			r1	r0	rd	0	0	3	ADD REG	add rd, r0, r1	Adds two registers together.
8			r1	r0	rd	1	0	3	SUB REG	sub rd, r0, r1	Subtracts two registers together.
9				label	rd		0	4	JAL	jal rd, label	Jumps to the address given and saves the old program counter in a register.	Immediate is an offset from the current program counter.
10				r0	rd		0	5	JALR	jal rd, r0	Jumps to an address in a register and saves the old program counter in a register.
11			label	r1	r0	0	0	6	BLT	blt r0, r1, label	Branches to an address if r0 < r1 (signed).	Immediate is an offset from the current program counter.
12			label	r1	r0	1	0	6	BLTU	bltu r0, r1, label	Branches to an address if r0 < r1 (unsigned).	^
13			label	r1	r0	2	0	6	BEQ	beq r0, r1, label	Branches to an address if r0 == r1.	^
14			label	r1	r0	3	0	6	BNE	bne r0, r1, label	Branches to an address if r0 != r1.	^
15				imm	rd	0	0	7	LLI	lli rd, imm	Loads the immediate into the lower 12 bits of a register, sign extended.
16				imm	rd	1	0	7	AUI	aui rd, imm	Adds the immediate into the upper 12 bits of a register.
17												All immediates are sign extended.
18				mr	r0		1	0	MLOAD	mload mr, r0	Loads a register into a machine register.
19				mr	rd		1	1	MSTORE	mstore rd, mr	Stores a machine register into a register.
20				mr	rd		1	2	MSWAP	mswap mr, rd	Swaps the contents of a machine register and a register.
21							1	3	SYSCALL	syscall	Performs a syscall in user mode to machine mode.
22							1	4	MRET	mret	Performs a return from an interrupt, updating the current mode and exception enables.
23							1	5
24							1	6
25							1	7
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