nac3/nac3core/src/codegen/stmt.rs
David Mak e95586f61e core: Fix IR generation of for loop containing break/continue
Fix cases where the body BB would have two terminators because of a
preceding continue/break statement already emitting a terminator.
2023-11-01 13:21:27 +08:00

1187 lines
48 KiB
Rust

use super::{
super::symbol_resolver::ValueEnum,
expr::destructure_range,
irrt::{handle_slice_indices, list_slice_assignment},
CodeGenContext, CodeGenerator,
};
use crate::{
codegen::{
expr::gen_binop_expr,
gen_in_range_check,
},
toplevel::{DefinitionId, TopLevelDef},
typecheck::typedef::{FunSignature, Type, TypeEnum},
};
use inkwell::{
attributes::{Attribute, AttributeLoc},
basic_block::BasicBlock,
types::BasicTypeEnum,
values::{BasicValue, BasicValueEnum, FunctionValue, PointerValue},
IntPredicate,
};
use nac3parser::ast::{
Constant, ExcepthandlerKind, Expr, ExprKind, Location, Stmt, StmtKind, StrRef,
};
use std::convert::TryFrom;
/// See [CodeGenerator::gen_var_alloc].
pub fn gen_var<'ctx, 'a>(
ctx: &mut CodeGenContext<'ctx, 'a>,
ty: BasicTypeEnum<'ctx>,
name: Option<&str>,
) -> Result<PointerValue<'ctx>, String> {
// Restore debug location
let di_loc = ctx.debug_info.0.create_debug_location(
ctx.ctx,
ctx.current_loc.row as u32,
ctx.current_loc.column as u32,
ctx.debug_info.2,
None,
);
// put the alloca in init block
let current = ctx.builder.get_insert_block().unwrap();
// position before the last branching instruction...
ctx.builder.position_before(&ctx.init_bb.get_last_instruction().unwrap());
ctx.builder.set_current_debug_location(di_loc);
let ptr = ctx.builder.build_alloca(ty, name.unwrap_or(""));
ctx.builder.position_at_end(current);
ctx.builder.set_current_debug_location(di_loc);
Ok(ptr)
}
/// See [CodeGenerator::gen_store_target].
pub fn gen_store_target<'ctx, 'a, G: CodeGenerator>(
generator: &mut G,
ctx: &mut CodeGenContext<'ctx, 'a>,
pattern: &Expr<Option<Type>>,
name: Option<&str>,
) -> Result<PointerValue<'ctx>, String> {
// very similar to gen_expr, but we don't do an extra load at the end
// and we flatten nested tuples
Ok(match &pattern.node {
ExprKind::Name { id, .. } => match ctx.var_assignment.get(id) {
None => {
let ptr_ty = ctx.get_llvm_type(generator, pattern.custom.unwrap());
let ptr = generator.gen_var_alloc(ctx, ptr_ty, name)?;
ctx.var_assignment.insert(*id, (ptr, None, 0));
ptr
}
Some(v) => {
let (ptr, counter) = (v.0, v.2);
ctx.var_assignment.insert(*id, (ptr, None, counter));
ptr
}
}
ExprKind::Attribute { value, attr, .. } => {
let index = ctx.get_attr_index(value.custom.unwrap(), *attr);
let val = generator.gen_expr(ctx, value)?.unwrap().to_basic_value_enum(
ctx,
generator,
value.custom.unwrap(),
)?;
let ptr = if let BasicValueEnum::PointerValue(v) = val {
v
} else {
unreachable!();
};
unsafe {
ctx.builder.build_in_bounds_gep(
ptr,
&[
ctx.ctx.i32_type().const_zero(),
ctx.ctx.i32_type().const_int(index as u64, false),
],
name.unwrap_or(""),
)
}
}
ExprKind::Subscript { value, slice, .. } => {
assert!(matches!(
ctx.unifier.get_ty_immutable(value.custom.unwrap()).as_ref(),
TypeEnum::TList { .. },
));
let i32_type = ctx.ctx.i32_type();
let zero = i32_type.const_zero();
let v = generator
.gen_expr(ctx, value)?
.unwrap()
.to_basic_value_enum(ctx, generator, value.custom.unwrap())?
.into_pointer_value();
let len = ctx
.build_gep_and_load(v, &[zero, i32_type.const_int(1, false)], Some("len"))
.into_int_value();
let raw_index = generator
.gen_expr(ctx, slice)?
.unwrap()
.to_basic_value_enum(ctx, generator, slice.custom.unwrap())?
.into_int_value();
let raw_index = ctx.builder.build_int_s_extend(
raw_index,
generator.get_size_type(ctx.ctx),
"sext",
);
// handle negative index
let is_negative = ctx.builder.build_int_compare(
IntPredicate::SLT,
raw_index,
generator.get_size_type(ctx.ctx).const_zero(),
"is_neg",
);
let adjusted = ctx.builder.build_int_add(raw_index, len, "adjusted");
let index = ctx
.builder
.build_select(is_negative, adjusted, raw_index, "index")
.into_int_value();
// unsigned less than is enough, because negative index after adjustment is
// bigger than the length (for unsigned cmp)
let bound_check = ctx.builder.build_int_compare(
IntPredicate::ULT,
index,
len,
"inbound",
);
ctx.make_assert(
generator,
bound_check,
"0:IndexError",
"index {0} out of bounds 0:{1}",
[Some(raw_index), Some(len), None],
slice.location,
);
unsafe {
let arr_ptr = ctx
.build_gep_and_load(v, &[i32_type.const_zero(), i32_type.const_zero()], Some("arr.addr"))
.into_pointer_value();
ctx.builder.build_gep(arr_ptr, &[index], name.unwrap_or(""))
}
}
_ => unreachable!(),
})
}
/// See [CodeGenerator::gen_assign].
pub fn gen_assign<'ctx, 'a, G: CodeGenerator>(
generator: &mut G,
ctx: &mut CodeGenContext<'ctx, 'a>,
target: &Expr<Option<Type>>,
value: ValueEnum<'ctx>,
) -> Result<(), String> {
match &target.node {
ExprKind::Tuple { elts, .. } => {
if let BasicValueEnum::StructValue(v) =
value.to_basic_value_enum(ctx, generator, target.custom.unwrap())?
{
for (i, elt) in elts.iter().enumerate() {
let v = ctx
.builder
.build_extract_value(v, u32::try_from(i).unwrap(), "struct_elem")
.unwrap();
generator.gen_assign(ctx, elt, v.into())?;
}
} else {
unreachable!()
}
}
ExprKind::Subscript { value: ls, slice, .. }
if matches!(&slice.node, ExprKind::Slice { .. }) =>
{
if let ExprKind::Slice { lower, upper, step } = &slice.node {
let ls = generator
.gen_expr(ctx, ls)?
.unwrap()
.to_basic_value_enum(ctx, generator, ls.custom.unwrap())?
.into_pointer_value();
let (start, end, step) =
handle_slice_indices(lower, upper, step, ctx, generator, ls)?;
let value = value
.to_basic_value_enum(ctx, generator, target.custom.unwrap())?
.into_pointer_value();
let ty =
if let TypeEnum::TList { ty } = &*ctx.unifier.get_ty(target.custom.unwrap()) {
ctx.get_llvm_type(generator, *ty)
} else {
unreachable!()
};
let src_ind = handle_slice_indices(&None, &None, &None, ctx, generator, value)?;
list_slice_assignment(generator, ctx, ty, ls, (start, end, step), value, src_ind)
} else {
unreachable!()
}
}
_ => {
let name = if let ExprKind::Name { id, .. } = &target.node {
format!("{}.addr", id.to_string())
} else {
String::from("target.addr")
};
let ptr = generator.gen_store_target(ctx, target, Some(name.as_str()))?;
if let ExprKind::Name { id, .. } = &target.node {
let (_, static_value, counter) = ctx.var_assignment.get_mut(id).unwrap();
*counter += 1;
if let ValueEnum::Static(s) = &value {
*static_value = Some(s.clone());
}
}
let val = value.to_basic_value_enum(ctx, generator, target.custom.unwrap())?;
ctx.builder.build_store(ptr, val);
}
};
Ok(())
}
/// See [CodeGenerator::gen_for].
pub fn gen_for<'ctx, 'a, G: CodeGenerator>(
generator: &mut G,
ctx: &mut CodeGenContext<'ctx, 'a>,
stmt: &Stmt<Option<Type>>,
) -> Result<(), String> {
if let StmtKind::For { iter, target, body, orelse, .. } = &stmt.node {
// var_assignment static values may be changed in another branch
// if so, remove the static value as it may not be correct in this branch
let var_assignment = ctx.var_assignment.clone();
let int32 = ctx.ctx.i32_type();
let size_t = generator.get_size_type(ctx.ctx);
let zero = int32.const_zero();
let current = ctx.builder.get_insert_block().and_then(|bb| bb.get_parent()).unwrap();
let body_bb = ctx.ctx.append_basic_block(current, "for.body");
let cont_bb = ctx.ctx.append_basic_block(current, "for.end");
// if there is no orelse, we just go to cont_bb
let orelse_bb = if orelse.is_empty() {
cont_bb
} else {
ctx.ctx.append_basic_block(current, "for.orelse")
};
// Whether the iterable is a range() expression
let is_iterable_range_expr = ctx.unifier.unioned(iter.custom.unwrap(), ctx.primitives.range);
// The BB containing the increment expression
let incr_bb = ctx.ctx.append_basic_block(current, "for.incr");
// The BB containing the loop condition check
let cond_bb = ctx.ctx.append_basic_block(current, "for.cond");
// store loop bb information and restore it later
let loop_bb = ctx.loop_target.replace((incr_bb, cont_bb));
let iter_val = generator.gen_expr(ctx, iter)?.unwrap().to_basic_value_enum(
ctx,
generator,
iter.custom.unwrap(),
)?;
if is_iterable_range_expr {
let iter_val = iter_val.into_pointer_value();
// Internal variable for loop; Cannot be assigned
let i = generator.gen_var_alloc(ctx, int32.into(), Some("for.i.addr"))?;
// Variable declared in "target" expression of the loop; Can be reassigned *or* shadowed
let target_i = generator.gen_store_target(ctx, target, Some("for.target.addr"))?;
let (start, stop, step) = destructure_range(ctx, iter_val);
ctx.builder.build_store(i, start);
// Check "If step is zero, ValueError is raised."
let rangenez = ctx.builder.build_int_compare(IntPredicate::NE, step, int32.const_zero(), "");
ctx.make_assert(
generator,
rangenez,
"ValueError",
"range() arg 3 must not be zero",
[None, None, None],
ctx.current_loc
);
ctx.builder.build_unconditional_branch(cond_bb);
{
ctx.builder.position_at_end(cond_bb);
ctx.builder.build_conditional_branch(
gen_in_range_check(
ctx,
ctx.builder.build_load(i, "").into_int_value(),
stop,
step
),
body_bb,
orelse_bb,
);
}
ctx.builder.position_at_end(incr_bb);
let next_i = ctx.builder.build_int_add(
ctx.builder.build_load(i, "").into_int_value(),
step,
"inc",
);
ctx.builder.build_store(i, next_i);
ctx.builder.build_unconditional_branch(cond_bb);
ctx.builder.position_at_end(body_bb);
ctx.builder.build_store(target_i, ctx.builder.build_load(i, "").into_int_value());
gen_block(generator, ctx, body.iter())?;
} else {
let index_addr = generator.gen_var_alloc(ctx, size_t.into(), Some("for.index.addr"))?;
ctx.builder.build_store(index_addr, size_t.const_zero());
let len = ctx
.build_gep_and_load(
iter_val.into_pointer_value(),
&[zero, int32.const_int(1, false)],
Some("len")
)
.into_int_value();
ctx.builder.build_unconditional_branch(cond_bb);
ctx.builder.position_at_end(cond_bb);
let index = ctx.builder.build_load(index_addr, "for.index").into_int_value();
let cmp = ctx.builder.build_int_compare(IntPredicate::SLT, index, len, "cond");
ctx.builder.build_conditional_branch(cmp, body_bb, orelse_bb);
ctx.builder.position_at_end(incr_bb);
let index = ctx.builder.build_load(index_addr, "").into_int_value();
let inc = ctx.builder.build_int_add(index, size_t.const_int(1, true), "inc");
ctx.builder.build_store(index_addr, inc);
ctx.builder.build_unconditional_branch(cond_bb);
ctx.builder.position_at_end(body_bb);
let arr_ptr = ctx
.build_gep_and_load(iter_val.into_pointer_value(), &[zero, zero], Some("arr.addr"))
.into_pointer_value();
let index = ctx.builder.build_load(index_addr, "for.index").into_int_value();
let val = ctx.build_gep_and_load(arr_ptr, &[index], Some("val"));
generator.gen_assign(ctx, target, val.into())?;
gen_block(generator, ctx, body.iter())?;
}
for (k, (_, _, counter)) in var_assignment.iter() {
let (_, static_val, counter2) = ctx.var_assignment.get_mut(k).unwrap();
if counter != counter2 {
*static_val = None;
}
}
if !ctx.is_terminated() {
ctx.builder.build_unconditional_branch(incr_bb);
}
if !orelse.is_empty() {
ctx.builder.position_at_end(orelse_bb);
gen_block(generator, ctx, orelse.iter())?;
if !ctx.is_terminated() {
ctx.builder.build_unconditional_branch(cont_bb);
}
}
for (k, (_, _, counter)) in var_assignment.iter() {
let (_, static_val, counter2) = ctx.var_assignment.get_mut(k).unwrap();
if counter != counter2 {
*static_val = None;
}
}
ctx.builder.position_at_end(cont_bb);
ctx.loop_target = loop_bb;
} else {
unreachable!()
}
Ok(())
}
/// See [CodeGenerator::gen_while].
pub fn gen_while<'ctx, 'a, G: CodeGenerator>(
generator: &mut G,
ctx: &mut CodeGenContext<'ctx, 'a>,
stmt: &Stmt<Option<Type>>,
) -> Result<(), String> {
if let StmtKind::While { test, body, orelse, .. } = &stmt.node {
// var_assignment static values may be changed in another branch
// if so, remove the static value as it may not be correct in this branch
let var_assignment = ctx.var_assignment.clone();
let current = ctx.builder.get_insert_block().unwrap().get_parent().unwrap();
let test_bb = ctx.ctx.append_basic_block(current, "while.test");
let body_bb = ctx.ctx.append_basic_block(current, "while.body");
let cont_bb = ctx.ctx.append_basic_block(current, "while.cont");
// if there is no orelse, we just go to cont_bb
let orelse_bb =
if orelse.is_empty() { cont_bb } else { ctx.ctx.append_basic_block(current, "while.orelse") };
// store loop bb information and restore it later
let loop_bb = ctx.loop_target.replace((test_bb, cont_bb));
ctx.builder.build_unconditional_branch(test_bb);
ctx.builder.position_at_end(test_bb);
let test = generator.gen_expr(ctx, test)?.unwrap().to_basic_value_enum(
ctx,
generator,
test.custom.unwrap(),
)?;
if let BasicValueEnum::IntValue(test) = test {
ctx.builder.build_conditional_branch(generator.bool_to_i1(ctx, test), body_bb, orelse_bb);
} else {
unreachable!()
};
ctx.builder.position_at_end(body_bb);
gen_block(generator, ctx, body.iter())?;
for (k, (_, _, counter)) in var_assignment.iter() {
let (_, static_val, counter2) = ctx.var_assignment.get_mut(k).unwrap();
if counter != counter2 {
*static_val = None;
}
}
if !ctx.is_terminated() {
ctx.builder.build_unconditional_branch(test_bb);
}
if !orelse.is_empty() {
ctx.builder.position_at_end(orelse_bb);
gen_block(generator, ctx, orelse.iter())?;
if !ctx.is_terminated() {
ctx.builder.build_unconditional_branch(cont_bb);
}
}
for (k, (_, _, counter)) in var_assignment.iter() {
let (_, static_val, counter2) = ctx.var_assignment.get_mut(k).unwrap();
if counter != counter2 {
*static_val = None;
}
}
ctx.builder.position_at_end(cont_bb);
ctx.loop_target = loop_bb;
} else {
unreachable!()
}
Ok(())
}
/// See [CodeGenerator::gen_if].
pub fn gen_if<'ctx, 'a, G: CodeGenerator>(
generator: &mut G,
ctx: &mut CodeGenContext<'ctx, 'a>,
stmt: &Stmt<Option<Type>>,
) -> Result<(), String> {
if let StmtKind::If { test, body, orelse, .. } = &stmt.node {
// var_assignment static values may be changed in another branch
// if so, remove the static value as it may not be correct in this branch
let var_assignment = ctx.var_assignment.clone();
let current = ctx.builder.get_insert_block().unwrap().get_parent().unwrap();
let test_bb = ctx.ctx.append_basic_block(current, "if.test");
let body_bb = ctx.ctx.append_basic_block(current, "if.body");
let mut cont_bb = None;
// if there is no orelse, we just go to cont_bb
let orelse_bb = if orelse.is_empty() {
cont_bb = Some(ctx.ctx.append_basic_block(current, "if.cont"));
cont_bb.unwrap()
} else {
ctx.ctx.append_basic_block(current, "if.orelse")
};
ctx.builder.build_unconditional_branch(test_bb);
ctx.builder.position_at_end(test_bb);
let test = generator.gen_expr(ctx, test)?
.unwrap()
.to_basic_value_enum(ctx, generator, test.custom.unwrap())?;
if let BasicValueEnum::IntValue(test) = test {
ctx.builder.build_conditional_branch(generator.bool_to_i1(ctx, test), body_bb, orelse_bb);
} else {
unreachable!()
};
ctx.builder.position_at_end(body_bb);
gen_block(generator, ctx, body.iter())?;
for (k, (_, _, counter)) in var_assignment.iter() {
let (_, static_val, counter2) = ctx.var_assignment.get_mut(k).unwrap();
if counter != counter2 {
*static_val = None;
}
}
if !ctx.is_terminated() {
if cont_bb.is_none() {
cont_bb = Some(ctx.ctx.append_basic_block(current, "cont"));
}
ctx.builder.build_unconditional_branch(cont_bb.unwrap());
}
if !orelse.is_empty() {
ctx.builder.position_at_end(orelse_bb);
gen_block(generator, ctx, orelse.iter())?;
if !ctx.is_terminated() {
if cont_bb.is_none() {
cont_bb = Some(ctx.ctx.append_basic_block(current, "cont"));
}
ctx.builder.build_unconditional_branch(cont_bb.unwrap());
}
}
if let Some(cont_bb) = cont_bb {
ctx.builder.position_at_end(cont_bb);
}
for (k, (_, _, counter)) in var_assignment.iter() {
let (_, static_val, counter2) = ctx.var_assignment.get_mut(k).unwrap();
if counter != counter2 {
*static_val = None;
}
}
} else {
unreachable!()
}
Ok(())
}
pub fn final_proxy<'ctx, 'a>(
ctx: &mut CodeGenContext<'ctx, 'a>,
target: BasicBlock<'ctx>,
block: BasicBlock<'ctx>,
final_data: &mut (PointerValue, Vec<BasicBlock<'ctx>>, Vec<BasicBlock<'ctx>>),
) {
let (final_state, final_targets, final_paths) = final_data;
let prev = ctx.builder.get_insert_block().unwrap();
ctx.builder.position_at_end(block);
unsafe {
ctx.builder.build_store(*final_state, target.get_address().unwrap());
}
ctx.builder.position_at_end(prev);
final_targets.push(target);
final_paths.push(block);
}
/// Inserts the declaration of the builtin function with the specified `symbol` name, and returns
/// the function.
pub fn get_builtins<'ctx, 'a>(
generator: &mut dyn CodeGenerator,
ctx: &mut CodeGenContext<'ctx, 'a>,
symbol: &str,
) -> FunctionValue<'ctx> {
ctx.module.get_function(symbol).unwrap_or_else(|| {
let ty = match symbol {
"__nac3_raise" => ctx
.ctx
.void_type()
.fn_type(&[ctx.get_llvm_type(generator, ctx.primitives.exception).into()], false),
"__nac3_resume" => ctx.ctx.void_type().fn_type(&[], false),
"__nac3_end_catch" => ctx.ctx.void_type().fn_type(&[], false),
_ => unimplemented!(),
};
let fun = ctx.module.add_function(symbol, ty, None);
if symbol == "__nac3_raise" || symbol == "__nac3_resume" {
fun.add_attribute(
AttributeLoc::Function,
ctx.ctx.create_enum_attribute(Attribute::get_named_enum_kind_id("noreturn"), 0),
);
}
fun
})
}
pub fn exn_constructor<'ctx, 'a>(
ctx: &mut CodeGenContext<'ctx, 'a>,
obj: Option<(Type, ValueEnum<'ctx>)>,
_fun: (&FunSignature, DefinitionId),
mut args: Vec<(Option<StrRef>, ValueEnum<'ctx>)>,
generator: &mut dyn CodeGenerator,
) -> Result<Option<BasicValueEnum<'ctx>>, String> {
let (zelf_ty, zelf) = obj.unwrap();
let zelf = zelf.to_basic_value_enum(ctx, generator, zelf_ty)?.into_pointer_value();
let int32 = ctx.ctx.i32_type();
let zero = int32.const_zero();
let zelf_id = {
if let TypeEnum::TObj { obj_id, .. } = &*ctx.unifier.get_ty(zelf_ty) {
obj_id.0
} else {
unreachable!()
}
};
let defs = ctx.top_level.definitions.read();
let def = defs[zelf_id].read();
let zelf_name =
if let TopLevelDef::Class { name, .. } = &*def { *name } else { unreachable!() };
let exception_name = format!("{}:{}", ctx.resolver.get_exception_id(zelf_id), zelf_name);
unsafe {
let id_ptr = ctx.builder.build_in_bounds_gep(zelf, &[zero, zero], "exn.id");
let id = ctx.resolver.get_string_id(&exception_name);
ctx.builder.build_store(id_ptr, int32.const_int(id as u64, false));
let empty_string = ctx.gen_const(generator, &Constant::Str("".into()), ctx.primitives.str);
let ptr =
ctx.builder.build_in_bounds_gep(zelf, &[zero, int32.const_int(5, false)], "exn.msg");
let msg = if !args.is_empty() {
args.remove(0).1.to_basic_value_enum(ctx, generator, ctx.primitives.str)?
} else {
empty_string
};
ctx.builder.build_store(ptr, msg);
for i in [6, 7, 8].iter() {
let value = if !args.is_empty() {
args.remove(0).1.to_basic_value_enum(ctx, generator, ctx.primitives.int64)?
} else {
ctx.ctx.i64_type().const_zero().into()
};
let ptr = ctx.builder.build_in_bounds_gep(
zelf,
&[zero, int32.const_int(*i, false)],
"exn.param",
);
ctx.builder.build_store(ptr, value);
}
// set file, func to empty string
for i in [1, 4].iter() {
let ptr = ctx.builder.build_in_bounds_gep(
zelf,
&[zero, int32.const_int(*i, false)],
"exn.str",
);
ctx.builder.build_store(ptr, empty_string);
}
// set ints to zero
for i in [2, 3].iter() {
let ptr = ctx.builder.build_in_bounds_gep(
zelf,
&[zero, int32.const_int(*i, false)],
"exn.ints",
);
ctx.builder.build_store(ptr, zero);
}
}
Ok(Some(zelf.into()))
}
/// Generates IR for a `raise` statement.
///
/// * `exception` - The exception thrown by the `raise` statement.
/// * `loc` - The location where the exception is raised from.
pub fn gen_raise<'ctx, 'a>(
generator: &mut dyn CodeGenerator,
ctx: &mut CodeGenContext<'ctx, 'a>,
exception: Option<&BasicValueEnum<'ctx>>,
loc: Location,
) {
if let Some(exception) = exception {
unsafe {
let int32 = ctx.ctx.i32_type();
let zero = int32.const_zero();
let exception = exception.into_pointer_value();
let file_ptr = ctx.builder.build_in_bounds_gep(
exception,
&[zero, int32.const_int(1, false)],
"file_ptr",
);
let filename = ctx.gen_string(generator, loc.file.0);
ctx.builder.build_store(file_ptr, filename);
let row_ptr = ctx.builder.build_in_bounds_gep(
exception,
&[zero, int32.const_int(2, false)],
"row_ptr",
);
ctx.builder.build_store(row_ptr, int32.const_int(loc.row as u64, false));
let col_ptr = ctx.builder.build_in_bounds_gep(
exception,
&[zero, int32.const_int(3, false)],
"col_ptr",
);
ctx.builder.build_store(col_ptr, int32.const_int(loc.column as u64, false));
let current_fun = ctx.builder.get_insert_block().unwrap().get_parent().unwrap();
let fun_name = ctx.gen_string(generator, current_fun.get_name().to_str().unwrap());
let name_ptr = ctx.builder.build_in_bounds_gep(
exception,
&[zero, int32.const_int(4, false)],
"name_ptr",
);
ctx.builder.build_store(name_ptr, fun_name);
}
let raise = get_builtins(generator, ctx, "__nac3_raise");
let exception = *exception;
ctx.build_call_or_invoke(raise, &[exception], "raise");
} else {
let resume = get_builtins(generator, ctx, "__nac3_resume");
ctx.build_call_or_invoke(resume, &[], "resume");
}
ctx.builder.build_unreachable();
}
/// Generates IR for a `try` statement.
pub fn gen_try<'ctx, 'a, G: CodeGenerator>(
generator: &mut G,
ctx: &mut CodeGenContext<'ctx, 'a>,
target: &Stmt<Option<Type>>,
) -> Result<(), String> {
if let StmtKind::Try { body, handlers, orelse, finalbody, .. } = &target.node {
// if we need to generate anything related to exception, we must have personality defined
let personality_symbol = ctx.top_level.personality_symbol.as_ref().unwrap();
let personality = ctx.module.get_function(personality_symbol).unwrap_or_else(|| {
let ty = ctx.ctx.i32_type().fn_type(&[], true);
ctx.module.add_function(personality_symbol, ty, None)
});
let exception_type = ctx.get_llvm_type(generator, ctx.primitives.exception);
let ptr_type = ctx.ctx.i8_type().ptr_type(inkwell::AddressSpace::default());
let current_block = ctx.builder.get_insert_block().unwrap();
let current_fun = current_block.get_parent().unwrap();
let landingpad = ctx.ctx.append_basic_block(current_fun, "try.landingpad");
let dispatcher = ctx.ctx.append_basic_block(current_fun, "try.dispatch");
let mut dispatcher_end = dispatcher;
ctx.builder.position_at_end(dispatcher);
let exn = ctx.builder.build_phi(exception_type, "exn");
ctx.builder.position_at_end(current_block);
let mut cleanup = None;
let mut old_loop_target = None;
let mut old_return = None;
let mut final_data = None;
let has_cleanup = !finalbody.is_empty();
if has_cleanup {
let final_state = generator.gen_var_alloc(ctx, ptr_type.into(), Some("try.final_state.addr"))?;
final_data = Some((final_state, Vec::new(), Vec::new()));
if let Some((continue_target, break_target)) = ctx.loop_target {
let break_proxy = ctx.ctx.append_basic_block(current_fun, "try.break");
let continue_proxy = ctx.ctx.append_basic_block(current_fun, "try.continue");
final_proxy(ctx, break_target, break_proxy, final_data.as_mut().unwrap());
final_proxy(ctx, continue_target, continue_proxy, final_data.as_mut().unwrap());
old_loop_target = ctx.loop_target.replace((continue_proxy, break_proxy));
}
let return_proxy = ctx.ctx.append_basic_block(current_fun, "try.return");
if let Some(return_target) = ctx.return_target {
final_proxy(ctx, return_target, return_proxy, final_data.as_mut().unwrap());
} else {
let return_target = ctx.ctx.append_basic_block(current_fun, "try.return_target");
ctx.builder.position_at_end(return_target);
let return_value = ctx.return_buffer.map(|v| ctx.builder.build_load(v, "$ret"));
ctx.builder.build_return(return_value.as_ref().map(|v| v as &dyn BasicValue));
ctx.builder.position_at_end(current_block);
final_proxy(ctx, return_target, return_proxy, final_data.as_mut().unwrap());
}
old_return = ctx.return_target.replace(return_proxy);
cleanup = Some(ctx.ctx.append_basic_block(current_fun, "try.cleanup"));
}
let mut clauses = Vec::new();
let mut found_catch_all = false;
for handler_node in handlers.iter() {
let ExcepthandlerKind::ExceptHandler { type_, .. } = &handler_node.node;
// none or Exception
if type_.is_none()
|| ctx
.unifier
.unioned(type_.as_ref().unwrap().custom.unwrap(), ctx.primitives.exception)
{
clauses.push(None);
found_catch_all = true;
break;
} else {
let type_ = type_.as_ref().unwrap();
let exn_name = ctx.resolver.get_type_name(
&ctx.top_level.definitions.read(),
&mut ctx.unifier,
type_.custom.unwrap(),
);
let obj_id = if let TypeEnum::TObj { obj_id, .. } = &*ctx.unifier.get_ty(type_.custom.unwrap()) {
*obj_id
} else {
unreachable!()
};
let exception_name = format!("{}:{}", ctx.resolver.get_exception_id(obj_id.0), exn_name);
let exn_id = ctx.resolver.get_string_id(&exception_name);
let exn_id_global =
ctx.module.add_global(ctx.ctx.i32_type(), None, &format!("exn.{}", exn_id));
exn_id_global.set_initializer(&ctx.ctx.i32_type().const_int(exn_id as u64, false));
clauses.push(Some(exn_id_global.as_pointer_value().as_basic_value_enum()));
}
}
let mut all_clauses = clauses.clone();
if let Some(old_clauses) = &ctx.outer_catch_clauses {
if !found_catch_all {
all_clauses.extend_from_slice(&old_clauses.0)
}
}
let old_clauses = ctx.outer_catch_clauses.replace((all_clauses, dispatcher, exn));
let old_unwind = ctx.unwind_target.replace(landingpad);
gen_block(generator, ctx, body.iter())?;
if ctx.builder.get_insert_block().unwrap().get_terminator().is_none() {
gen_block(generator, ctx, orelse.iter())?;
}
let body = ctx.builder.get_insert_block().unwrap();
// reset old_clauses and old_unwind
let (all_clauses, _, _) = ctx.outer_catch_clauses.take().unwrap();
ctx.outer_catch_clauses = old_clauses;
ctx.unwind_target = old_unwind;
ctx.return_target = old_return;
ctx.loop_target = old_loop_target.or(ctx.loop_target).take();
let old_unwind = if !finalbody.is_empty() {
let final_landingpad = ctx.ctx.append_basic_block(current_fun, "try.catch.final");
ctx.builder.position_at_end(final_landingpad);
ctx.builder.build_landing_pad(
ctx.ctx.struct_type(&[ptr_type.into(), exception_type], false),
personality,
&[],
true,
"try.catch.final",
);
ctx.builder.build_unconditional_branch(cleanup.unwrap());
ctx.builder.position_at_end(body);
ctx.unwind_target.replace(final_landingpad)
} else {
None
};
// run end_catch before continue/break/return
let mut final_proxy_lambda =
|ctx: &mut CodeGenContext<'ctx, 'a>,
target: BasicBlock<'ctx>,
block: BasicBlock<'ctx>| final_proxy(ctx, target, block, final_data.as_mut().unwrap());
let mut redirect_lambda = |ctx: &mut CodeGenContext<'ctx, 'a>,
target: BasicBlock<'ctx>,
block: BasicBlock<'ctx>| {
ctx.builder.position_at_end(block);
ctx.builder.build_unconditional_branch(target);
ctx.builder.position_at_end(body);
};
let redirect = if has_cleanup {
&mut final_proxy_lambda
as &mut dyn FnMut(&mut CodeGenContext<'ctx, 'a>, BasicBlock<'ctx>, BasicBlock<'ctx>)
} else {
&mut redirect_lambda
as &mut dyn FnMut(&mut CodeGenContext<'ctx, 'a>, BasicBlock<'ctx>, BasicBlock<'ctx>)
};
let resume = get_builtins(generator, ctx, "__nac3_resume");
let end_catch = get_builtins(generator, ctx, "__nac3_end_catch");
if let Some((continue_target, break_target)) = ctx.loop_target.take() {
let break_proxy = ctx.ctx.append_basic_block(current_fun, "try.break");
let continue_proxy = ctx.ctx.append_basic_block(current_fun, "try.continue");
ctx.builder.position_at_end(break_proxy);
ctx.builder.build_call(end_catch, &[], "end_catch");
ctx.builder.position_at_end(continue_proxy);
ctx.builder.build_call(end_catch, &[], "end_catch");
ctx.builder.position_at_end(body);
redirect(ctx, break_target, break_proxy);
redirect(ctx, continue_target, continue_proxy);
ctx.loop_target = Some((continue_proxy, break_proxy));
old_loop_target = Some((continue_target, break_target));
}
let return_proxy = ctx.ctx.append_basic_block(current_fun, "try.return");
ctx.builder.position_at_end(return_proxy);
ctx.builder.build_call(end_catch, &[], "end_catch");
let return_target = ctx.return_target.take().unwrap_or_else(|| {
let doreturn = ctx.ctx.append_basic_block(current_fun, "try.doreturn");
ctx.builder.position_at_end(doreturn);
let return_value = ctx.return_buffer.map(|v| ctx.builder.build_load(v, "$ret"));
ctx.builder.build_return(return_value.as_ref().map(|v| v as &dyn BasicValue));
doreturn
});
redirect(ctx, return_target, return_proxy);
ctx.return_target = Some(return_proxy);
old_return = Some(return_target);
let mut post_handlers = Vec::new();
let exnid = if !handlers.is_empty() {
ctx.builder.position_at_end(dispatcher);
unsafe {
let zero = ctx.ctx.i32_type().const_zero();
let exnid_ptr = ctx.builder.build_gep(
exn.as_basic_value().into_pointer_value(),
&[zero, zero],
"exnidptr",
);
Some(ctx.builder.build_load(exnid_ptr, "exnid"))
}
} else {
None
};
for (handler_node, exn_type) in handlers.iter().zip(clauses.iter()) {
let ExcepthandlerKind::ExceptHandler { type_, name, body } = &handler_node.node;
let handler_bb = ctx.ctx.append_basic_block(current_fun, "try.handler");
ctx.builder.position_at_end(handler_bb);
if let Some(name) = name {
let exn_ty = ctx.get_llvm_type(generator, type_.as_ref().unwrap().custom.unwrap());
let exn_store = generator.gen_var_alloc(ctx, exn_ty, Some("try.exn_store.addr"))?;
ctx.var_assignment.insert(*name, (exn_store, None, 0));
ctx.builder.build_store(exn_store, exn.as_basic_value());
}
gen_block(generator, ctx, body.iter())?;
let current = ctx.builder.get_insert_block().unwrap();
// only need to call end catch if not terminated
// otherwise, we already handled in return/break/continue/raise
if current.get_terminator().is_none() {
ctx.builder.build_call(end_catch, &[], "end_catch");
}
post_handlers.push(current);
ctx.builder.position_at_end(dispatcher_end);
if let Some(exn_type) = exn_type {
let dispatcher_cont =
ctx.ctx.append_basic_block(current_fun, "try.dispatcher_cont");
let actual_id = exnid.unwrap().into_int_value();
let expected_id = ctx
.builder
.build_load(exn_type.into_pointer_value(), "expected_id")
.into_int_value();
let result = ctx.builder.build_int_compare(IntPredicate::EQ, actual_id, expected_id, "exncheck");
ctx.builder.build_conditional_branch(result, handler_bb, dispatcher_cont);
dispatcher_end = dispatcher_cont;
} else {
ctx.builder.build_unconditional_branch(handler_bb);
break;
}
}
ctx.unwind_target = old_unwind;
ctx.loop_target = old_loop_target.or(ctx.loop_target).take();
ctx.return_target = old_return;
ctx.builder.position_at_end(landingpad);
let clauses: Vec<_> = if finalbody.is_empty() { &all_clauses } else { &clauses }
.iter()
.map(|v| v.unwrap_or(ptr_type.const_zero().into()))
.collect();
let landingpad_value = ctx
.builder
.build_landing_pad(
ctx.ctx.struct_type(&[ptr_type.into(), exception_type], false),
personality,
&clauses,
has_cleanup,
"try.landingpad",
)
.into_struct_value();
let exn_val = ctx.builder.build_extract_value(landingpad_value, 1, "exn").unwrap();
ctx.builder.build_unconditional_branch(dispatcher);
exn.add_incoming(&[(&exn_val, landingpad)]);
if dispatcher_end.get_terminator().is_none() {
ctx.builder.position_at_end(dispatcher_end);
if let Some(cleanup) = cleanup {
ctx.builder.build_unconditional_branch(cleanup);
} else if let Some((_, outer_dispatcher, phi)) = ctx.outer_catch_clauses {
phi.add_incoming(&[(&exn_val, dispatcher_end)]);
ctx.builder.build_unconditional_branch(outer_dispatcher);
} else {
ctx.build_call_or_invoke(resume, &[], "resume");
ctx.builder.build_unreachable();
}
}
if finalbody.is_empty() {
let tail = ctx.ctx.append_basic_block(current_fun, "try.tail");
if body.get_terminator().is_none() {
ctx.builder.position_at_end(body);
ctx.builder.build_unconditional_branch(tail);
}
if matches!(cleanup, Some(cleanup) if cleanup.get_terminator().is_none()) {
ctx.builder.position_at_end(cleanup.unwrap());
ctx.builder.build_unconditional_branch(tail);
}
for post_handler in post_handlers {
if post_handler.get_terminator().is_none() {
ctx.builder.position_at_end(post_handler);
ctx.builder.build_unconditional_branch(tail);
}
}
ctx.builder.position_at_end(tail);
} else {
// exception path
let cleanup = cleanup.unwrap();
ctx.builder.position_at_end(cleanup);
gen_block(generator, ctx, finalbody.iter())?;
if !ctx.is_terminated() {
ctx.build_call_or_invoke(resume, &[], "resume");
ctx.builder.build_unreachable();
}
// normal path
let (final_state, mut final_targets, final_paths) = final_data.unwrap();
let tail = ctx.ctx.append_basic_block(current_fun, "try.tail");
final_targets.push(tail);
let finalizer = ctx.ctx.append_basic_block(current_fun, "try.finally");
ctx.builder.position_at_end(finalizer);
gen_block(generator, ctx, finalbody.iter())?;
if !ctx.is_terminated() {
let dest = ctx.builder.build_load(final_state, "final_dest");
ctx.builder.build_indirect_branch(dest, &final_targets);
}
for block in final_paths.iter() {
if block.get_terminator().is_none() {
ctx.builder.position_at_end(*block);
ctx.builder.build_unconditional_branch(finalizer);
}
}
for block in [body].iter().chain(post_handlers.iter()) {
if block.get_terminator().is_none() {
ctx.builder.position_at_end(*block);
unsafe {
ctx.builder.build_store(final_state, tail.get_address().unwrap());
}
ctx.builder.build_unconditional_branch(finalizer);
}
}
ctx.builder.position_at_end(tail);
}
Ok(())
} else {
unreachable!()
}
}
/// See [CodeGenerator::gen_with].
pub fn gen_with<'ctx, 'a, G: CodeGenerator>(
_: &mut G,
_: &mut CodeGenContext<'ctx, 'a>,
stmt: &Stmt<Option<Type>>,
) -> Result<(), String> {
// TODO: Implement with statement after finishing exceptions
Err(format!("With statement with custom types is not yet supported (at {})", stmt.location))
}
/// Generates IR for a `return` statement.
pub fn gen_return<'ctx, 'a, G: CodeGenerator>(
generator: &mut G,
ctx: &mut CodeGenContext<'ctx, 'a>,
value: &Option<Box<Expr<Option<Type>>>>,
) -> Result<(), String> {
let func = ctx.builder.get_insert_block().and_then(|bb| bb.get_parent()).unwrap();
let value = value
.as_ref()
.map(|v_expr| {
generator.gen_expr(ctx, v_expr).and_then(|v| {
v.unwrap().to_basic_value_enum(ctx, generator, v_expr.custom.unwrap())
})
})
.transpose()?;
if let Some(return_target) = ctx.return_target {
if let Some(value) = value {
ctx.builder.build_store(ctx.return_buffer.unwrap(), value);
}
ctx.builder.build_unconditional_branch(return_target);
} else if ctx.need_sret {
// sret
ctx.builder.build_store(ctx.return_buffer.unwrap(), value.unwrap());
ctx.builder.build_return(None);
} else {
// Remap boolean return type into i1
let value = value.map(|v| {
let expected_ty = func.get_type().get_return_type().unwrap();
let ret_val = v.as_basic_value_enum();
if expected_ty.is_int_type() && ret_val.is_int_value() {
let ret_type = expected_ty.into_int_type();
let ret_val = ret_val.into_int_value();
if ret_type.get_bit_width() == 1 && ret_val.get_type().get_bit_width() != 1 {
generator.bool_to_i1(ctx, ret_val)
} else {
ret_val
}.into()
} else {
ret_val
}
});
let value = value.as_ref().map(|v| v as &dyn BasicValue);
ctx.builder.build_return(value.into());
}
Ok(())
}
/// See [CodeGenerator::gen_stmt].
pub fn gen_stmt<'ctx, 'a, G: CodeGenerator>(
generator: &mut G,
ctx: &mut CodeGenContext<'ctx, 'a>,
stmt: &Stmt<Option<Type>>,
) -> Result<(), String> {
ctx.current_loc = stmt.location;
let loc = ctx.debug_info.0.create_debug_location(
ctx.ctx,
ctx.current_loc.row as u32,
ctx.current_loc.column as u32,
ctx.debug_info.2,
None,
);
ctx.builder.set_current_debug_location(loc);
match &stmt.node {
StmtKind::Pass { .. } => {}
StmtKind::Expr { value, .. } => {
generator.gen_expr(ctx, value)?;
}
StmtKind::Return { value, .. } => {
gen_return(generator, ctx, value)?;
}
StmtKind::AnnAssign { target, value, .. } => {
if let Some(value) = value {
let value = generator.gen_expr(ctx, value)?.unwrap();
generator.gen_assign(ctx, target, value)?;
}
}
StmtKind::Assign { targets, value, .. } => {
let value = generator.gen_expr(ctx, value)?.unwrap();
for target in targets.iter() {
generator.gen_assign(ctx, target, value.clone())?;
}
}
StmtKind::Continue { .. } => {
ctx.builder.build_unconditional_branch(ctx.loop_target.unwrap().0);
}
StmtKind::Break { .. } => {
ctx.builder.build_unconditional_branch(ctx.loop_target.unwrap().1);
}
StmtKind::If { .. } => generator.gen_if(ctx, stmt)?,
StmtKind::While { .. } => generator.gen_while(ctx, stmt)?,
StmtKind::For { .. } => generator.gen_for(ctx, stmt)?,
StmtKind::With { .. } => generator.gen_with(ctx, stmt)?,
StmtKind::AugAssign { target, op, value, .. } => {
let value = gen_binop_expr(generator, ctx, target, op, value, stmt.location, true)?;
generator.gen_assign(ctx, target, value.unwrap())?;
}
StmtKind::Try { .. } => gen_try(generator, ctx, stmt)?,
StmtKind::Raise { exc, .. } => {
if let Some(exc) = exc {
let exc = generator.gen_expr(ctx, exc)?.unwrap().to_basic_value_enum(
ctx,
generator,
exc.custom.unwrap(),
)?;
gen_raise(generator, ctx, Some(&exc), stmt.location);
} else {
gen_raise(generator, ctx, None, stmt.location);
}
}
StmtKind::Assert { test, msg, .. } => {
let test = generator.gen_expr(ctx, test)?.unwrap().to_basic_value_enum(
ctx,
generator,
test.custom.unwrap(),
)?;
let err_msg = match msg {
Some(msg) => generator.gen_expr(ctx, msg)?.unwrap().to_basic_value_enum(
ctx,
generator,
msg.custom.unwrap(),
)?,
None => ctx.gen_string(generator, ""),
};
ctx.make_assert_impl(
generator,
test.into_int_value(),
"0:AssertionError",
err_msg,
[None, None, None],
stmt.location,
)
}
_ => unimplemented!()
};
Ok(())
}
/// Generates IR for a block statement contains `stmts`.
pub fn gen_block<'ctx, 'a, 'b, G: CodeGenerator, I: Iterator<Item = &'b Stmt<Option<Type>>>>(
generator: &mut G,
ctx: &mut CodeGenContext<'ctx, 'a>,
stmts: I,
) -> Result<(), String> {
for stmt in stmts {
generator.gen_stmt(ctx, stmt)?;
if ctx.is_terminated() {
break;
}
}
Ok(())
}