Instructions

# S - signed
# U - unsigned
# P - pseudo-instruction

# Arithmetic
add     t1, t2, t3
addi    t1, t2, -100
sub     t1, t2, t3
neg     t1, t2        # (P)

# Logical
and     t1, t2, t3
andi    t1, t2, -100
or      t1, t2, t3
ori     t1, t2, -100
xor     t1, t2, t3
xori    t1, t2, -100
not     t1, t2        # (P)

# Shifts
sll     t1, t2, t3    # left logical
slli    t1, t2, 33    # left logical
sra     t1, t2, t3    # right arithmetic (S)
srai    t1, t2, 33    # right arithmetic (S)
srl     t1, t2, t3    # right logical (U)
srli    t1, t2, 33    # right logical (U)

# Multiplication
mul     t1, t2, t3    # t1 <- t2*t3[31:0]
mulh    t1, t2, t3    # t1 <- t2*t3[63:32] (S)
mulhu   t1, t2, t3    # t1 <- t2*t3[63:32] (U)
mulhsu  t1, t2, t3    # t1 <- t2*t3[63:32] (t2 S, t3 U)

# Division, remainder
div     t1, t2, t3    # S
divu    t1, t2, t3    # U
rem     t1, t2, t3    # S
remu    t1, t2, t3    # U

# Load value from memory at (t2-100) to t1
lb      t1, -100(t2)  # sign-extended 8-bit
lbu     t1, -100(t2)  # zero-extended 8-bit
lh      t1, -100(t2)  # sign-extended 16-bit
lhu     t1, -100(t2)  # zero-extended 16-bit
lw      t1, -100(t2)  # 32-bit

# Store value t1 to memory at (t2-100)
sb      t1, -100(t2)  # 8-bit
sh      t1, -100(t2)  # 16-bit
sw      t1, -100(t2)  # 32-bit

# System
ecall
ebreak

# Upper immediates
lui     t1, imm       # t1 <- imm << 12
auipc   t1, imm       # t1 <- pc + (imm << 12)

# Other
mv      t1, t2        # t1 <- t2 (P)
li      t1, 1000      # t1 <- 1000 (P)
la      t1, label     # t1 <- label (P)
nop                   # no operation (P)

# Branches
beq     t1, t2, target  # if t1 == t2
bne     t1, t2, target  # if t1 != t2
blt     t1, t2, target  # if t1 < t2 (S)
bltu    t1, t2, target  # if t1 < t2 (U)
bgt     t1, t2, target  # if t1 > t2 (S) (P)
bgtu    t1, t2, target  # if t1 > t2 (U) (P)
ble     t1, t2, target  # if t1 <= t2 (S) (P)
bleu    t1, t2, target  # if t1 <= t2 (U) (P)
bge     t1, t2, target  # if t1 >= t2 (S)
bgeu    t1, t2, target  # if t1 >= t2 (U)
beqz    t1, target      # if t1 == 0 (P)
bnez    t1, target      # if t1 != 0 (P)
bltz    t1, target      # if t1 < 0 (P)
bgtz    t1, target      # if t1 > 0 (P)
blez    t1, target      # if t1 <= 0 (P)
bgez    t1, target      # if t1 >= 0 (P)

# Comparisons
slt     t1, t2, t3      # t1 <- t2 < t3 (S)
sltu    t1, t2, t3      # t1 <- t2 < t3 (U)
slti    t1, t2, -100    # t1 <- t2 < -100 (S)
sltiu   t1, t2, -100    # t1 <- t2 < -100 (U)
sgt     t1, t2, t3      # t1 <- t2 > t3 (S) (P)
sgtu    t1, t2, t3      # t1 <- t2 > t3 (U) (P)
seqz    t1, t2          # t1 <- t2 == 0 (P)
snez    t1, t2          # t1 <- t2 != 0 (P)
sltz    t1, t2          # t1 <- t2 < 0 (P)
sgtz    t1, t2          # t1 <- t2 > 0 (P)

# Jump and link
jal     t1, target      # t1 <- pc+4; pc = target
jal     target          # ra <- pc+4; pc = target (P)
j       target          # pc = target (P)
b       target          # pc = target (P)
jalr    t1, t2, -100    # t1 <- pc+4; pc = t2-100
jalr    t2, -100        # ra <- pc+4; pc = t2-100 (P)
jalr    t2              # ra <- pc+4; pc = t2 (P)
jr      t2, -100        # pc = t2-100 (P)
jr      t2              # pc = t2 (P)
ret                     # pc = ra (P)

Registers

Register  ABI name  Saver
x0        zero      --
x1        ra        Caller
x2        sp        Callee
x3        gp        --
x4        tp        Callee
x5-x7     t0-t2     Caller
x8        s0/fp     Callee
x9        s1        Callee
x10-x17   a0-a7     Caller
x18-x27   s2-s11    Callee
x28-x31   t3-t6     Caller

Sys. calls

1  PrintInt
2  PrintFloat
3  PrintDouble
4  PrintString
5  ReadInt
6  ReadFloat
7  ReadDouble
8  ReadString
9  Sbrk
10 Exit
11 PrintChar
12 ReadChar
17 GetCWD
30 Time
31 MidiOut
32 Sleep
33 MidiOutSync
34 PrintIntHex
35 PrintIntBinary
36 PrintIntUnsigned
40 RandSeed
41 RandInt
42 RandIntRange
43 RandFloat
44 RandDouble
50 ConfirmDialog
51 InputDialogInt
52 InputDialogFloat
53 InputDialogDouble
54 InputDialogString
55 MessageDialog
56 MessageDialogInt
57 Close
58 MessageDialogDouble
59 MessageDialogString
60 MessageDialogFloat
62 LSeek
63 Read
64 Write
93 Exit2 

Directives

# code section
.text           
# data section
.data           

.byte   x
.half   x
.word   x
.dword  x
.float  x
.double x

# align to 2^n
.align  n       
# reserve n bytes
.space  n       

# chars
.ascii  "abc"   
# null-terminated chars
.asciz  "abc"   
# alias for .asciz
.string "abc"   

.globl  f

.eqv    N, 10

.include "abc.asm"

.macro
.end_macro