nac3/nac3artiq/src/codegen.rs
David Mak c93ad152d7 core: Codegen for ellipsis expression as NotImplemented
A lot of refactoring was performed, specifically with relaxing
expression codegen to return Option in case where ellipsis are used
within a subexpression.
2023-12-08 18:00:51 +08:00

700 lines
27 KiB
Rust

use nac3core::{
codegen::{
expr::gen_call,
stmt::{gen_block, gen_with},
CodeGenContext, CodeGenerator,
},
symbol_resolver::ValueEnum,
toplevel::{DefinitionId, GenCall},
typecheck::typedef::{FunSignature, FuncArg, Type, TypeEnum}
};
use nac3parser::ast::{Expr, ExprKind, Located, Stmt, StmtKind, StrRef};
use inkwell::{
context::Context, module::Linkage, types::IntType, values::BasicValueEnum, AddressSpace,
};
use pyo3::{PyObject, PyResult, Python, types::{PyDict, PyList}};
use crate::{symbol_resolver::InnerResolver, timeline::TimeFns};
use std::{
collections::hash_map::DefaultHasher,
collections::HashMap,
hash::{Hash, Hasher},
sync::Arc,
};
/// The parallelism mode within a block.
#[derive(Copy, Clone, Eq, PartialEq)]
enum ParallelMode {
/// No parallelism is currently registered for this context.
None,
/// Legacy (or shallow) parallelism. Default before NAC3.
///
/// Each statement within the `with` block is treated as statements to be executed in parallel.
Legacy,
/// Deep parallelism. Default since NAC3.
///
/// Each function call within the `with` block (except those within a nested `sequential` block)
/// are treated to be executed in parallel.
Deep
}
pub struct ArtiqCodeGenerator<'a> {
name: String,
/// The size of a `size_t` variable in bits.
size_t: u32,
/// Monotonic counter for naming `start`/`stop` variables used by `with parallel` blocks.
name_counter: u32,
/// Variable for tracking the start of a `with parallel` block.
start: Option<Expr<Option<Type>>>,
/// Variable for tracking the end of a `with parallel` block.
end: Option<Expr<Option<Type>>>,
timeline: &'a (dyn TimeFns + Sync),
/// The [ParallelMode] of the current parallel context.
///
/// The current parallel context refers to the nearest `with parallel` or `with legacy_parallel`
/// statement, which is used to determine when and how the timeline should be updated.
parallel_mode: ParallelMode,
}
impl<'a> ArtiqCodeGenerator<'a> {
pub fn new(
name: String,
size_t: u32,
timeline: &'a (dyn TimeFns + Sync),
) -> ArtiqCodeGenerator<'a> {
assert!(size_t == 32 || size_t == 64);
ArtiqCodeGenerator {
name,
size_t,
name_counter: 0,
start: None,
end: None,
timeline,
parallel_mode: ParallelMode::None,
}
}
/// If the generator is currently in a direct-`parallel` block context, emits IR that resets the
/// position of the timeline to the initial timeline position before entering the `parallel`
/// block.
///
/// Direct-`parallel` block context refers to when the generator is generating statements whose
/// closest parent `with` statement is a `with parallel` block.
fn timeline_reset_start<'ctx, 'b>(
&mut self,
ctx: &mut CodeGenContext<'ctx, 'b>
) -> Result<(), String> {
if let Some(start) = self.start.clone() {
let start_val = self.gen_expr(ctx, &start)?
.unwrap()
.to_basic_value_enum(ctx, self, start.custom.unwrap())?;
self.timeline.emit_at_mu(ctx, start_val);
}
Ok(())
}
/// If the generator is currently in a `parallel` block context, emits IR that updates the
/// maximum end position of the `parallel` block as specified by the timeline `end` value.
///
/// In general the `end` parameter should be set to `self.end` for updating the maximum end
/// position for the current `parallel` block. Other values can be passed in to update the
/// maximum end position for other `parallel` blocks.
///
/// `parallel`-block context refers to when the generator is generating statements within a
/// (possibly indirect) `parallel` block.
///
/// * `store_name` - The LLVM value name for the pointer to `end`. `.addr` will be appended to
/// the end of the provided value name.
fn timeline_update_end_max<'ctx, 'b>(
&mut self,
ctx: &mut CodeGenContext<'ctx, 'b>,
end: Option<Expr<Option<Type>>>,
store_name: Option<&str>,
) -> Result<(), String> {
if let Some(end) = end {
let old_end = self.gen_expr(ctx, &end)?
.unwrap()
.to_basic_value_enum(ctx, self, end.custom.unwrap())?;
let now = self.timeline.emit_now_mu(ctx);
let smax = ctx.module.get_function("llvm.smax.i64").unwrap_or_else(|| {
let i64 = ctx.ctx.i64_type();
ctx.module.add_function(
"llvm.smax.i64",
i64.fn_type(&[i64.into(), i64.into()], false),
None,
)
});
let max = ctx
.builder
.build_call(smax, &[old_end.into(), now.into()], "smax")
.try_as_basic_value()
.left()
.unwrap();
let end_store = self.gen_store_target(
ctx,
&end,
store_name.map(|name| format!("{name}.addr")).as_deref())?
.unwrap();
ctx.builder.build_store(end_store, max);
}
Ok(())
}
}
impl<'b> CodeGenerator for ArtiqCodeGenerator<'b> {
fn get_name(&self) -> &str {
&self.name
}
fn get_size_type<'ctx>(&self, ctx: &'ctx Context) -> IntType<'ctx> {
if self.size_t == 32 {
ctx.i32_type()
} else {
ctx.i64_type()
}
}
fn gen_block<'ctx, 'a, 'c, I: Iterator<Item=&'c Stmt<Option<Type>>>>(
&mut self,
ctx: &mut CodeGenContext<'ctx, 'a>,
stmts: I
) -> Result<(), String> where Self: Sized {
// Legacy parallel emits timeline end-update/timeline-reset after each top-level statement
// in the parallel block
if self.parallel_mode == ParallelMode::Legacy {
for stmt in stmts {
self.gen_stmt(ctx, stmt)?;
if ctx.is_terminated() {
break;
}
self.timeline_update_end_max(ctx, self.end.clone(), Some("end"))?;
self.timeline_reset_start(ctx)?;
}
Ok(())
} else {
gen_block(self, ctx, stmts)
}
}
fn gen_call<'ctx, 'a>(
&mut self,
ctx: &mut CodeGenContext<'ctx, 'a>,
obj: Option<(Type, ValueEnum<'ctx>)>,
fun: (&FunSignature, DefinitionId),
params: Vec<(Option<StrRef>, ValueEnum<'ctx>)>,
) -> Result<Option<BasicValueEnum<'ctx>>, String> {
let result = gen_call(self, ctx, obj, fun, params)?;
// Deep parallel emits timeline end-update/timeline-reset after each function call
if self.parallel_mode == ParallelMode::Deep {
self.timeline_update_end_max(ctx, self.end.clone(), Some("end"))?;
self.timeline_reset_start(ctx)?;
}
Ok(result)
}
fn gen_with<'ctx, 'a>(
&mut self,
ctx: &mut CodeGenContext<'ctx, 'a>,
stmt: &Stmt<Option<Type>>,
) -> Result<(), String> {
if let StmtKind::With { items, body, .. } = &stmt.node {
if items.len() == 1 && items[0].optional_vars.is_none() {
let item = &items[0];
// Behavior of parallel and sequential:
// Each function call (indirectly, can be inside a sequential block) within a parallel
// block will update the end variable to the maximum now_mu in the block.
// Each function call directly inside a parallel block will reset the timeline after
// execution. A parallel block within a sequential block (or not within any block) will
// set the timeline to the max now_mu within the block (and the outer max now_mu will also
// be updated).
//
// Implementation: We track the start and end separately.
// - If there is a start variable, it indicates that we are directly inside a
// parallel block and we have to reset the timeline after every function call.
// - If there is a end variable, it indicates that we are (indirectly) inside a
// parallel block, and we should update the max end value.
if let ExprKind::Name { id, ctx: name_ctx } = &item.context_expr.node {
if id == &"parallel".into() || id == &"legacy_parallel".into() {
let old_start = self.start.take();
let old_end = self.end.take();
let old_parallel_mode = self.parallel_mode;
let now = if let Some(old_start) = &old_start {
self.gen_expr(ctx, old_start)?
.unwrap()
.to_basic_value_enum(ctx, self, old_start.custom.unwrap())?
} else {
self.timeline.emit_now_mu(ctx)
};
// Emulate variable allocation, as we need to use the CodeGenContext
// HashMap to store our variable due to lifetime limitation
// Note: we should be able to store variables directly if generic
// associative type is used by limiting the lifetime of CodeGenerator to
// the LLVM Context.
// The name is guaranteed to be unique as users cannot use this as variable
// name.
self.start = old_start.clone().map_or_else(
|| {
let start = format!("with-{}-start", self.name_counter).into();
let start_expr = Located {
// location does not matter at this point
location: stmt.location,
node: ExprKind::Name { id: start, ctx: name_ctx.clone() },
custom: Some(ctx.primitives.int64),
};
let start = self
.gen_store_target(ctx, &start_expr, Some("start.addr"))?
.unwrap();
ctx.builder.build_store(start, now);
Ok(Some(start_expr)) as Result<_, String>
},
|v| Ok(Some(v)),
)?;
let end = format!("with-{}-end", self.name_counter).into();
let end_expr = Located {
// location does not matter at this point
location: stmt.location,
node: ExprKind::Name { id: end, ctx: name_ctx.clone() },
custom: Some(ctx.primitives.int64),
};
let end = self.gen_store_target(ctx, &end_expr, Some("end.addr"))?.unwrap();
ctx.builder.build_store(end, now);
self.end = Some(end_expr);
self.name_counter += 1;
self.parallel_mode = match id.to_string().as_str() {
"parallel" => ParallelMode::Deep,
"legacy_parallel" => ParallelMode::Legacy,
_ => unreachable!(),
};
self.gen_block(ctx, body.iter())?;
let current = ctx.builder.get_insert_block().unwrap();
// if the current block is terminated, move before the terminator
// we want to set the timeline before reaching the terminator
// TODO: This may be unsound if there are multiple exit paths in the
// block... e.g.
// if ...:
// return
// Perhaps we can fix this by using actual with block?
let reset_position = if let Some(terminator) = current.get_terminator() {
ctx.builder.position_before(&terminator);
true
} else {
false
};
// set duration
let end_expr = self.end.take().unwrap();
let end_val = self
.gen_expr(ctx, &end_expr)?
.unwrap()
.to_basic_value_enum(ctx, self, end_expr.custom.unwrap())?;
// inside a sequential block
if old_start.is_none() {
self.timeline.emit_at_mu(ctx, end_val);
}
// inside a parallel block, should update the outer max now_mu
self.timeline_update_end_max(ctx, old_end.clone(), Some("outer.end"))?;
self.parallel_mode = old_parallel_mode;
self.end = old_end;
self.start = old_start;
if reset_position {
ctx.builder.position_at_end(current);
}
return Ok(());
} else if id == &"sequential".into() {
// For deep parallel, temporarily take away start to avoid function calls in
// the block from resetting the timeline.
// This does not affect legacy parallel, as the timeline will be reset after
// this block finishes execution.
let start = self.start.take();
self.gen_block(ctx, body.iter())?;
self.start = start;
// Reset the timeline when we are exiting the sequential block
// Legacy parallel does not need this, since it will be reset after codegen
// for this statement is completed
if self.parallel_mode == ParallelMode::Deep {
self.timeline_reset_start(ctx)?;
}
return Ok(());
}
}
}
// not parallel/sequential
gen_with(self, ctx, stmt)
} else {
unreachable!()
}
}
}
fn gen_rpc_tag<'ctx, 'a>(
ctx: &mut CodeGenContext<'ctx, 'a>,
ty: Type,
buffer: &mut Vec<u8>,
) -> Result<(), String> {
use nac3core::typecheck::typedef::TypeEnum::*;
let int32 = ctx.primitives.int32;
let int64 = ctx.primitives.int64;
let float = ctx.primitives.float;
let bool = ctx.primitives.bool;
let str = ctx.primitives.str;
let none = ctx.primitives.none;
if ctx.unifier.unioned(ty, int32) {
buffer.push(b'i');
} else if ctx.unifier.unioned(ty, int64) {
buffer.push(b'I');
} else if ctx.unifier.unioned(ty, float) {
buffer.push(b'f');
} else if ctx.unifier.unioned(ty, bool) {
buffer.push(b'b');
} else if ctx.unifier.unioned(ty, str) {
buffer.push(b's');
} else if ctx.unifier.unioned(ty, none) {
buffer.push(b'n');
} else {
let ty_enum = ctx.unifier.get_ty(ty);
match &*ty_enum {
TTuple { ty } => {
buffer.push(b't');
buffer.push(ty.len() as u8);
for ty in ty {
gen_rpc_tag(ctx, *ty, buffer)?;
}
}
TList { ty } => {
buffer.push(b'l');
gen_rpc_tag(ctx, *ty, buffer)?;
}
_ => return Err(format!("Unsupported type: {:?}", ctx.unifier.stringify(ty))),
}
}
Ok(())
}
fn rpc_codegen_callback_fn<'ctx, 'a>(
ctx: &mut CodeGenContext<'ctx, 'a>,
obj: Option<(Type, ValueEnum<'ctx>)>,
fun: (&FunSignature, DefinitionId),
args: Vec<(Option<StrRef>, ValueEnum<'ctx>)>,
generator: &mut dyn CodeGenerator,
) -> Result<Option<BasicValueEnum<'ctx>>, String> {
let ptr_type = ctx.ctx.i8_type().ptr_type(inkwell::AddressSpace::default());
let size_type = generator.get_size_type(ctx.ctx);
let int8 = ctx.ctx.i8_type();
let int32 = ctx.ctx.i32_type();
let tag_ptr_type = ctx.ctx.struct_type(&[ptr_type.into(), size_type.into()], false);
let service_id = int32.const_int(fun.1.0 as u64, false);
// -- setup rpc tags
let mut tag = Vec::new();
if obj.is_some() {
tag.push(b'O');
}
for arg in fun.0.args.iter() {
gen_rpc_tag(ctx, arg.ty, &mut tag)?;
}
tag.push(b':');
gen_rpc_tag(ctx, fun.0.ret, &mut tag)?;
let mut hasher = DefaultHasher::new();
tag.hash(&mut hasher);
let hash = format!("{}", hasher.finish());
let tag_ptr = ctx
.module
.get_global(hash.as_str())
.unwrap_or_else(|| {
let tag_arr_ptr = ctx.module.add_global(
int8.array_type(tag.len() as u32),
None,
format!("tagptr{}", fun.1 .0).as_str(),
);
tag_arr_ptr.set_initializer(&int8.const_array(
&tag.iter().map(|v| int8.const_int(*v as u64, false)).collect::<Vec<_>>(),
));
tag_arr_ptr.set_linkage(Linkage::Private);
let tag_ptr = ctx.module.add_global(tag_ptr_type, None, &hash);
tag_ptr.set_linkage(Linkage::Private);
tag_ptr.set_initializer(&ctx.ctx.const_struct(
&[
tag_arr_ptr.as_pointer_value().const_cast(ptr_type).into(),
size_type.const_int(tag.len() as u64, false).into(),
],
false,
));
tag_ptr
})
.as_pointer_value();
let arg_length = args.len() + if obj.is_some() { 1 } else { 0 };
let stacksave = ctx.module.get_function("llvm.stacksave").unwrap_or_else(|| {
ctx.module.add_function("llvm.stacksave", ptr_type.fn_type(&[], false), None)
});
let stackrestore = ctx.module.get_function("llvm.stackrestore").unwrap_or_else(|| {
ctx.module.add_function(
"llvm.stackrestore",
ctx.ctx.void_type().fn_type(&[ptr_type.into()], false),
None,
)
});
let stackptr = ctx.builder.build_call(stacksave, &[], "rpc.stack");
let args_ptr = ctx.builder.build_array_alloca(
ptr_type,
ctx.ctx.i32_type().const_int(arg_length as u64, false),
"argptr",
);
// -- rpc args handling
let mut keys = fun.0.args.clone();
let mut mapping = HashMap::new();
for (key, value) in args.into_iter() {
mapping.insert(key.unwrap_or_else(|| keys.remove(0).name), value);
}
// default value handling
for k in keys.into_iter() {
mapping.insert(
k.name,
ctx.gen_symbol_val(generator, &k.default_value.unwrap(), k.ty).into()
);
}
// reorder the parameters
let mut real_params = fun
.0
.args
.iter()
.map(|arg| mapping.remove(&arg.name).unwrap().to_basic_value_enum(ctx, generator, arg.ty))
.collect::<Result<Vec<_>, _>>()?;
if let Some(obj) = obj {
if let ValueEnum::Static(obj) = obj.1 {
real_params.insert(0, obj.get_const_obj(ctx, generator));
} else {
// should be an error here...
panic!("only host object is allowed");
}
}
for (i, arg) in real_params.iter().enumerate() {
let arg_slot = generator.gen_var_alloc(ctx, arg.get_type(), Some(&format!("rpc.arg{i}"))).unwrap();
ctx.builder.build_store(arg_slot, *arg);
let arg_slot = ctx.builder.build_bitcast(arg_slot, ptr_type, "rpc.arg");
let arg_ptr = unsafe {
ctx.builder.build_gep(
args_ptr,
&[int32.const_int(i as u64, false)],
&format!("rpc.arg{}", i),
)
};
ctx.builder.build_store(arg_ptr, arg_slot);
}
// call
let rpc_send = ctx.module.get_function("rpc_send").unwrap_or_else(|| {
ctx.module.add_function(
"rpc_send",
ctx.ctx.void_type().fn_type(
&[
int32.into(),
tag_ptr_type.ptr_type(AddressSpace::default()).into(),
ptr_type.ptr_type(AddressSpace::default()).into(),
],
false,
),
None,
)
});
ctx.builder.build_call(
rpc_send,
&[service_id.into(), tag_ptr.into(), args_ptr.into()],
"rpc.send",
);
// reclaim stack space used by arguments
ctx.builder.build_call(
stackrestore,
&[stackptr.try_as_basic_value().unwrap_left().into()],
"rpc.stackrestore",
);
// -- receive value:
// T result = {
// void *ret_ptr = alloca(sizeof(T));
// void *ptr = ret_ptr;
// loop: int size = rpc_recv(ptr);
// // Non-zero: Provide `size` bytes of extra storage for variable-length data.
// if(size) { ptr = alloca(size); goto loop; }
// else *(T*)ret_ptr
// }
let rpc_recv = ctx.module.get_function("rpc_recv").unwrap_or_else(|| {
ctx.module.add_function("rpc_recv", int32.fn_type(&[ptr_type.into()], false), None)
});
if ctx.unifier.unioned(fun.0.ret, ctx.primitives.none) {
ctx.build_call_or_invoke(rpc_recv, &[ptr_type.const_null().into()], "rpc_recv");
return Ok(None);
}
let prehead_bb = ctx.builder.get_insert_block().unwrap();
let current_function = prehead_bb.get_parent().unwrap();
let head_bb = ctx.ctx.append_basic_block(current_function, "rpc.head");
let alloc_bb = ctx.ctx.append_basic_block(current_function, "rpc.continue");
let tail_bb = ctx.ctx.append_basic_block(current_function, "rpc.tail");
let ret_ty = ctx.get_llvm_abi_type(generator, fun.0.ret);
let need_load = !ret_ty.is_pointer_type();
let slot = ctx.builder.build_alloca(ret_ty, "rpc.ret.slot");
let slotgen = ctx.builder.build_bitcast(slot, ptr_type, "rpc.ret.ptr");
ctx.builder.build_unconditional_branch(head_bb);
ctx.builder.position_at_end(head_bb);
let phi = ctx.builder.build_phi(ptr_type, "rpc.ptr");
phi.add_incoming(&[(&slotgen, prehead_bb)]);
let alloc_size = ctx
.build_call_or_invoke(rpc_recv, &[phi.as_basic_value()], "rpc.size.next")
.unwrap()
.into_int_value();
let is_done = ctx.builder.build_int_compare(
inkwell::IntPredicate::EQ,
int32.const_zero(),
alloc_size,
"rpc.done",
);
ctx.builder.build_conditional_branch(is_done, tail_bb, alloc_bb);
ctx.builder.position_at_end(alloc_bb);
let alloc_ptr = ctx.builder.build_array_alloca(ptr_type, alloc_size, "rpc.alloc");
let alloc_ptr = ctx.builder.build_bitcast(alloc_ptr, ptr_type, "rpc.alloc.ptr");
phi.add_incoming(&[(&alloc_ptr, alloc_bb)]);
ctx.builder.build_unconditional_branch(head_bb);
ctx.builder.position_at_end(tail_bb);
let result = ctx.builder.build_load(slot, "rpc.result");
if need_load {
ctx.builder.build_call(
stackrestore,
&[stackptr.try_as_basic_value().unwrap_left().into()],
"rpc.stackrestore",
);
}
Ok(Some(result))
}
pub fn attributes_writeback<'ctx, 'a>(
ctx: &mut CodeGenContext<'ctx, 'a>,
generator: &mut dyn CodeGenerator,
inner_resolver: &InnerResolver,
host_attributes: PyObject,
) -> Result<(), String> {
Python::with_gil(|py| -> PyResult<Result<(), String>> {
let host_attributes: &PyList = host_attributes.downcast(py)?;
let top_levels = ctx.top_level.definitions.read();
let globals = inner_resolver.global_value_ids.read();
let int32 = ctx.ctx.i32_type();
let zero = int32.const_zero();
let mut values = Vec::new();
let mut scratch_buffer = Vec::new();
for (_, val) in globals.iter() {
let val = val.as_ref(py);
let ty = inner_resolver.get_obj_type(py, val, &mut ctx.unifier, &top_levels, &ctx.primitives)?;
if let Err(ty) = ty {
return Ok(Err(ty))
}
let ty = ty.unwrap();
match &*ctx.unifier.get_ty(ty) {
TypeEnum::TObj { fields, obj_id, .. }
if *obj_id != ctx.primitives.option.get_obj_id(&ctx.unifier) =>
{
// we only care about primitive attributes
// for non-primitive attributes, they should be in another global
let mut attributes = Vec::new();
let obj = inner_resolver.get_obj_value(py, val, ctx, generator, ty)?.unwrap();
for (name, (field_ty, is_mutable)) in fields.iter() {
if !is_mutable {
continue
}
if gen_rpc_tag(ctx, *field_ty, &mut scratch_buffer).is_ok() {
attributes.push(name.to_string());
let index = ctx.get_attr_index(ty, *name);
values.push((*field_ty, ctx.build_gep_and_load(
obj.into_pointer_value(),
&[zero, int32.const_int(index as u64, false)], None)));
}
}
if !attributes.is_empty() {
let pydict = PyDict::new(py);
pydict.set_item("obj", val)?;
pydict.set_item("fields", attributes)?;
host_attributes.append(pydict)?;
}
},
TypeEnum::TList { ty: elem_ty } => {
if gen_rpc_tag(ctx, *elem_ty, &mut scratch_buffer).is_ok() {
let pydict = PyDict::new(py);
pydict.set_item("obj", val)?;
host_attributes.append(pydict)?;
values.push((ty, inner_resolver.get_obj_value(py, val, ctx, generator, ty)?.unwrap()));
}
},
_ => {}
}
}
let fun = FunSignature {
args: values.iter().enumerate().map(|(i, (ty, _))| FuncArg {
name: i.to_string().into(),
ty: *ty,
default_value: None
}).collect(),
ret: ctx.primitives.none,
vars: Default::default()
};
let args: Vec<_> = values.into_iter().map(|(_, val)| (None, ValueEnum::Dynamic(val))).collect();
if let Err(e) = rpc_codegen_callback_fn(ctx, None, (&fun, DefinitionId(0)), args, generator) {
return Ok(Err(e));
}
Ok(Ok(()))
}).unwrap()?;
Ok(())
}
pub fn rpc_codegen_callback() -> Arc<GenCall> {
Arc::new(GenCall::new(Box::new(|ctx, obj, fun, args, generator| {
rpc_codegen_callback_fn(ctx, obj, fun, args, generator)
})))
}