If statements work with the addition of jmp and jnz

This commit is contained in:
Nathan Braswell
2018-02-27 21:27:29 -05:00
parent adcebb3284
commit dad97a25a5
2 changed files with 51 additions and 4 deletions

View File

@@ -78,6 +78,8 @@ adt byte_inst {
add: add,
ldr: ldr,
str: str,
jmp: jmp,
jnz: jnz,
call,
ret
}
@@ -100,6 +102,13 @@ obj str {
var offset: int
var from_reg: int
}
obj jmp {
var offset: int
}
obj jnz {
var reg: int
var offset: int
}
fun to_string(b: byte_inst): string {
match (b) {
@@ -108,6 +117,8 @@ fun to_string(b: byte_inst): string {
byte_inst::add(a) return string("r") + a.to_reg + " = r" + a.a + " + r" + a.b
byte_inst::ldr(l) return string("r") + l.to_reg + " = ldr r" + l.from_reg + " (" + l.offset + ")"
byte_inst::str(s) return string("str(r") + s.to_reg + "(" + s.offset + ") <= r" + s.from_reg + ")"
byte_inst::jmp(j) return string("jmp(pc += ") + j.offset + ")"
byte_inst::jnz(j) return string("jmp(r") + j.reg + " != 0, pc += " + j.offset + ")"
byte_inst::call() return string("call")
byte_inst::ret() return string("ret")
}
@@ -164,8 +175,9 @@ obj bytecode_function (Object) {
res += "\t\t" + n->identifier.name + ": r0 + " + o
})
res += "\n\t bytecode\n"
var pc = 0
instructions.for_each(fun(b: byte_inst) {
res += "\t\t" + to_string(b) + "\n"
res += string("\t\t") + pc++ + string(": ") + to_string(b) + "\n"
})
return res
}
@@ -277,10 +289,19 @@ obj bytecode_generator (Object) {
return -1
}
fun generate_if_statement(node: *ast_node): int {
generate(node->if_statement.condition)
var cond_reg = generate(node->if_statement.condition)
var jnz_index = functions.last().instructions.size
emit_jnz(cond_reg,0)
generate(node->if_statement.then_part)
if (node->if_statement.else_part)
if (node->if_statement.else_part) {
var jmp_index = functions.last().instructions.size
emit_jmp(0)
functions.last().instructions[jnz_index].jnz.offset = functions.last().instructions.size - jnz_index
generate(node->if_statement.else_part)
functions.last().instructions[jmp_index].jmp.offset = functions.last().instructions.size - jmp_index
} else {
functions.last().instructions[jnz_index].jnz.offset = functions.last().instructions.size - jnz_index
}
return -1
}
fun generate_while_loop(node: *ast_node): int {
@@ -325,7 +346,10 @@ obj bytecode_generator (Object) {
return generate(node->cast.value)
}
fun generate_value(node: *ast_node): int {
return emit_imm(string_to_num<int>(node->value.string_value))
if (node->value.value_type->is_bool())
return emit_imm((node->value.string_value == "true") cast int)
else
return emit_imm(string_to_num<int>(node->value.string_value))
}
fun generate_code_block(node: *ast_node): int {
node->code_block.children.for_each(fun(child: *ast_node) {
@@ -410,6 +434,19 @@ obj bytecode_generator (Object) {
functions.last().instructions.add(byte_inst::str(s))
return -1
}
fun emit_jmp(offset: int): int {
var j: jmp
j.offset = offset
functions.last().instructions.add(byte_inst::jmp(j))
return -1
}
fun emit_jnz(reg: int, offset: int): int {
var j: jnz
j.reg = reg
j.offset = offset
functions.last().instructions.add(byte_inst::jnz(j))
return -1
}
fun emit_ret(): int {
functions.last().instructions.add(byte_inst::ret())
return -1
@@ -429,12 +466,16 @@ obj bytecode_generator (Object) {
stack_mem.size = 10
stack_mem.for_each(fun(i: ref int) { i = 0; })
for (var i = 0; i < main_entry.instructions.size; i++;) {
println(string("evaling: ") + i + ": " + to_string(main_entry.instructions[i]))
match(main_entry.instructions[i]) {
byte_inst::nop() {}
byte_inst::imm(i) registers[i.reg] = i.val
byte_inst::add(a) registers[a.to_reg] = registers[a.a] + registers[a.b]
byte_inst::ldr(l) registers[l.to_reg] = stack_mem[registers[l.from_reg] + l.offset]
byte_inst::str(s) stack_mem[registers[s.to_reg] + s.offset] = registers[s.from_reg]
byte_inst::jmp(j) i += j.offset - 1 // to counteract pc inc
byte_inst::jnz(j) if (registers[j.reg] != 0)
i += j.offset - 1 // to counteract pc inc
byte_inst::call() error("call")
/*byte_inst::ret() return stack_mem[registers[0]]*/
byte_inst::ret() {

View File

@@ -231,6 +231,12 @@ obj type (Object) {
}
return false
}
fun is_bool(): bool {
match (base) {
base_type::boolean() return true
}
return false
}
fun is_function(): bool {
match (base) {
base_type::function() return true