This is a proposal for the stack based vm. It is somewhat based on my previous StackVM. The only difference being that all operations happen on the stack and not in registers.
Registers
ip Points to the current instructions, adjusted after the instruction finishes
sp Points to the current top of the stack.
fp Points to the current stack frame.
Instructions
Instructions can (when it makes sense) dereference their argument.
TODO: Define instruction encoding.
Arithmetic
add
sub
mul
div unsigned division
sdiv signed divison
rem unsigned remainder
srem signed remainder
Floating-point arithmetic
fadd
fsub
fmul
fdiv
frem
fexp
Comparison
lt unsigned less than
slt signed less than
lteq unsigned less than or equal
slteq signed less than or equal
gt unsigned greater than
sgt signed greater than
gteq unsigned greater than or equal
sgteq signed greater than or equal
flt
fgt
Bitwise instructions
shr Shift right
shl Shift left
and
xor
or
not
Type conversions
inttofp Integer to floating-point
sinttofp Signed integer to floating-point
fptoint Floating-point to signed integer.
Stack instructions
asp Add a given value signed int to the stack pointer
load Load a value from fp + offset onto the stack
store Pop a value from the stack to fp + offset
push Push an immediate value onto the stack
Memory IO
read Read a value from an address and push it onto the stack
write Write a value from the stack to an address
copy Copy a value from an address to another address
move Move a value from an address to another address
malloc Allocate memory, pushing the address onto the stack
free Free memory
Control-flow
jmp Unconditional jump to address
jmpz Jump to address if top of the stack is 0
jmpnz Jump to address if top of the stack is not 0
call Unconditional jump to address. Pushes a stack frame
This is a proposal for the stack based vm. It is somewhat based on my previous StackVM. The only difference being that all operations happen on the stack and not in registers.
Registers
ipPoints to the current instructions, adjusted after the instruction finishesspPoints to the current top of the stack.fpPoints to the current stack frame.Instructions
Instructions can (when it makes sense) dereference their argument.
TODO: Define instruction encoding.
Arithmetic
addsubmuldivunsigned divisionsdivsigned divisonremunsigned remaindersremsigned remainderFloating-point arithmetic
faddfsubfmulfdivfremfexpComparison
ltunsigned less thansltsigned less thanltequnsigned less than or equalslteqsigned less than or equalgtunsigned greater thansgtsigned greater thangtequnsigned greater than or equalsgteqsigned greater than or equalfltfgtBitwise instructions
shrShift rightshlShift leftandxorornotType conversions
inttofpInteger to floating-pointsinttofpSigned integer to floating-pointfptointFloating-point to signed integer.Stack instructions
aspAdd a given valuesigned intto the stack pointerloadLoad a value fromfp + offsetonto the stackstorePop a value from the stack tofp + offsetpushPush an immediate value onto the stackMemory IO
readRead a value from an address and push it onto the stackwriteWrite a value from the stack to an addresscopyCopy a value from an address to another addressmoveMove a value from an address to another addressmallocAllocate memory, pushing the address onto the stackfreeFree memoryControl-flow
jmpUnconditional jump to addressjmpzJump to address if top of the stack is0jmpnzJump to address if top of the stack is not0callUnconditional jump to address. Pushes a stack frameretReturn from the current stack frame