Lox language
TODOs
- (Partially complete) unreachable code. if a "return" has been found in a local scope and we encounter other code directly following then we error
- values never read/used
RISCV-Meta-Assembler
RISC-V meta assembler that adds quality of life features to assembly
Memory map (pg 40 of TheReader)
- sp = 0xbfffffff
- 0->128K is reserved
- code starts at 0x00010001
- static data follows
- then Dynamic data
- and finally the Stack which grows downward.
Code example
import {
"stdio" as std
}
const {
GPIO_BASE = 0x10012000, // GPIO base
GPIO_RED = 0x400000
}
// Program code section.
// align code to 2^2 bytes = word alignment
// declares "main" symbol as global
// positions code at address 0x00010001
[alignTo word, global, at 0x00010001]
code main {
use std
addi sp,sp,-16 // allocate stack frame
sw ra,12(sp) // save return address
// Setup function parameters
lui a0,%hi(hello) // compute address of hello upper 20
addi a0,a0,%lo(hello) // lower 12
lui a1,%hi(world)
addi a1,a1,%lo(world)
call printf // call std's printf
lw ra,12(sp) // restore return address
addi sp,sp,16 // deallocate stack frame
li a0,0 // load return value 0
ret
}
[readOnly, alignTo bytes<4>, at 0x10000000]
data {
string hello "Hello, %s\n", // null terminated
string world "world",
char ['a', 'b', 'c'],
byte [0x20, 0x0f, 0x40, 0x0a]
half [0xff01,0xab02]
word [0xffff001],
}
[readWrite, alignTo bytes(4)]
data {
global int<4> count, // 4 byte integer = word
}
