use super::{call_args, custom, expr, function, generic, list, panic_expr};
use crate::plan::execution::lowering::graph::{DraftCursor, DraftFlow, DraftGraph, DraftTuple};
use crate::plan::execution::lowering::specialization::{
CompoundInhabitation, Representability, StoredValueShape,
};
use crate::plan::{execution, module};
pub(in crate::plan::execution::lowering) fn tuple_expr(
expression: &module::TupleExpr,
cursor: DraftCursor,
graph: &mut DraftGraph,
context: &mut super::super::LoweringContext,
) -> Representability<DraftFlow<DraftTuple>> {
use super::super::instruction::DraftTupleInstruction as I;
use module::TupleExprKind as E;
let elements = expression
.shape()
.iter()
.map(|shape| context.concrete_value_shape(shape))
.collect::<Vec<_>>();
if let CompoundInhabitation::Uninhabited(proof) =
context.representations.tuple_inhabitation(&elements)
{
return generic::tuple_never_expr(expression, &proof, cursor, graph, context)
.map(|_| DraftFlow::Diverged);
}
let stored = StoredValueShape::Tuple(elements.clone().into_boxed_slice());
match expression.kind() {
E::Value(values) => lower_values(values, cursor, graph, context).map(|flow| match flow {
DraftFlow::Diverged => DraftFlow::Diverged,
DraftFlow::Value {
mut cursor,
value: values,
} => {
let value = graph.tuple_instruction(
&mut cursor,
elements.clone().into_boxed_slice(),
I::Value(values),
);
DraftFlow::value(cursor, value)
}
}),
E::Constant(reference) => context.tuple_constant(reference).map(|id| {
let mut cursor = cursor;
let value = graph.tuple_instruction(
&mut cursor,
elements.clone().into_boxed_slice(),
I::Constant(execution::constant::ConstantId::new(id.index())),
);
DraftFlow::value(cursor, value)
}),
E::LocalGet { local, name: _ } => {
let value = cursor.scope().tuple(super::super::local::LocalKey::new(
super::super::local::LocalKind::Tuple,
local.0,
));
Representability::Inhabited(DraftFlow::value(cursor, value))
}
E::Call {
function,
args,
site,
} => call_args(args, cursor, graph, context).and_then(|flow| match flow {
DraftFlow::Diverged => Representability::Inhabited(DraftFlow::Diverged),
DraftFlow::Value {
mut cursor,
value: args,
} => context.tuple_function_id(function).map(|function| {
let value = graph.tuple_instruction(
&mut cursor,
elements.clone().into_boxed_slice(),
I::Call {
function,
args,
site: site.clone(),
},
);
DraftFlow::value(cursor, value)
}),
}),
E::FunctionCall {
function: value,
args,
site,
} => {
function::tuple_function_expr(value, cursor, graph, context).and_then(|flow| match flow
{
DraftFlow::Diverged => Representability::Inhabited(DraftFlow::Diverged),
DraftFlow::Value {
cursor,
value: function,
} => call_args(args, cursor, graph, context).map(|flow| match flow {
DraftFlow::Diverged => DraftFlow::Diverged,
DraftFlow::Value {
mut cursor,
value: args,
} => {
let value = graph.tuple_instruction(
&mut cursor,
elements.clone().into_boxed_slice(),
I::FunctionCall {
function: function.value().clone(),
args,
site: site.clone(),
},
);
DraftFlow::value(cursor, value)
}
}),
})
}
E::TupleIndex {
tuple: value,
index,
} => tuple_expr(value, cursor, graph, context).map(|flow| match flow {
DraftFlow::Diverged => DraftFlow::Diverged,
DraftFlow::Value {
mut cursor,
value: tuple,
} => {
let value = graph.tuple_instruction(
&mut cursor,
elements.clone().into_boxed_slice(),
I::TupleIndex {
tuple,
index: *index,
},
);
DraftFlow::value(cursor, value)
}
}),
E::CustomField(access) => {
custom::custom_expr(access.source(), cursor, graph, context).map(|flow| match flow {
DraftFlow::Diverged => DraftFlow::Diverged,
DraftFlow::Value {
mut cursor,
value: source,
} => {
let value = graph.tuple_instruction(
&mut cursor,
elements.clone().into_boxed_slice(),
I::CustomField {
source,
index: access.index(),
},
);
DraftFlow::value(cursor, value)
}
})
}
E::ListIndex { list: value, index } => list::tuple_list_expr(value, cursor, graph, context)
.map(|flow| match flow {
DraftFlow::Diverged => DraftFlow::Diverged,
DraftFlow::Value {
mut cursor,
value: list,
} => {
let value = graph.tuple_instruction(
&mut cursor,
elements.clone().into_boxed_slice(),
I::ListIndex {
list: list.value().clone(),
index: *index,
},
);
DraftFlow::value(cursor, value)
}
}),
E::Panic(value) => panic_expr(value, cursor, graph, context).map(|_| DraftFlow::Diverged),
E::BoolCase {
subject,
true_,
false_,
} => super::bool_case(
subject,
cursor,
super::case_lowering(graph, context, stored),
|cursor, graph, context| tuple_expr(true_, cursor, graph, context),
|cursor, graph, context| tuple_expr(false_, cursor, graph, context),
DraftTuple::from_ref,
),
E::IntCase {
subject,
clauses,
fallback,
} => super::int_case(
subject,
clauses,
fallback,
cursor,
super::case_lowering(graph, context, stored),
tuple_expr,
DraftTuple::from_ref,
),
E::StringCase {
subject,
clauses,
fallback,
} => super::string_case(
subject,
clauses,
fallback,
cursor,
super::case_lowering(graph, context, stored),
tuple_expr,
DraftTuple::from_ref,
),
E::FloatCase {
subject,
clauses,
fallback,
} => super::float_case(
subject,
clauses,
fallback,
cursor,
super::case_lowering(graph, context, stored),
tuple_expr,
DraftTuple::from_ref,
),
E::Block { steps, return_ } => super::super::step::steps(steps, cursor, graph, context)
.and_then(|flow| match flow {
DraftFlow::Diverged => Representability::Inhabited(DraftFlow::Diverged),
DraftFlow::Value { cursor, value: () } => {
tuple_expr(return_, cursor, graph, context)
}
}),
}
}
fn lower_values(
values: &[module::Expr],
mut cursor: DraftCursor,
graph: &mut DraftGraph,
context: &mut super::super::LoweringContext,
) -> Representability<DraftFlow<Vec<super::super::DraftValueRef>>> {
let mut lowered = Vec::with_capacity(values.len());
for value in values {
match expr(value, cursor, graph, context) {
Representability::Uninhabited => return Representability::Uninhabited,
Representability::Inhabited(DraftFlow::Diverged) => {
return Representability::Inhabited(DraftFlow::Diverged);
}
Representability::Inhabited(DraftFlow::Value {
cursor: next,
value,
}) => {
cursor = next;
lowered.push(value);
}
}
}
Representability::Inhabited(DraftFlow::value(cursor, lowered))
}
#[cfg(test)]
mod tests {
use super::tuple_expr;
use crate::plan::execution::lowering::graph::draft::DraftGraphBuilder;
use crate::plan::execution::lowering::graph::{DraftFlow, DraftValueRef};
use crate::plan::execution::lowering::specialization::{Representability, SpecializationKey};
use crate::plan::{
Expr, FunctionShape, FunctionTemplateId, IntExpr, PanicExpr, PanicSite, TupleExpr,
ValueShape, ValueType, monomorphic_function_instantiation,
};
#[derive(Debug, PartialEq, Eq)]
enum FlowOutcome {
Uninhabited,
Diverged,
Value,
}
fn flow_outcome<T>(flow: Representability<DraftFlow<T>>) -> FlowOutcome {
match flow {
Representability::Uninhabited => FlowOutcome::Uninhabited,
Representability::Inhabited(DraftFlow::Diverged) => FlowOutcome::Diverged,
Representability::Inhabited(DraftFlow::Value { .. }) => FlowOutcome::Value,
}
}
#[test]
fn tuple_construction_propagates_an_erased_element_specialization() {
let instantiation =
monomorphic_function_instantiation(0, FunctionShape::new(Vec::new(), ValueShape::Int));
let expressions = [
(
TupleExpr::value(
vec![Expr::int(IntExpr::value(1.into()))],
vec![ValueType::Int],
),
FlowOutcome::Value,
),
(
TupleExpr::value(
vec![Expr::int(IntExpr::panic(PanicExpr::panic_at(
None,
PanicSite::unknown(),
)))],
vec![ValueType::Int],
),
FlowOutcome::Diverged,
),
(
TupleExpr::value(
vec![Expr::int(IntExpr::call(instantiation, Vec::new()))],
vec![ValueType::Int],
),
FlowOutcome::Uninhabited,
),
];
let mut context =
crate::plan::execution::lowering::test_support::lowering_context(Vec::new());
context
.erased_specializations
.insert(SpecializationKey::monomorphic(FunctionTemplateId::new(0)));
let (mut graph, cursor) =
DraftGraphBuilder::<DraftValueRef, ()>::new(Vec::new(), Vec::new());
for (expression, expected) in expressions {
let cursor = graph.empty_block(cursor.scope().clone());
assert_eq!(
flow_outcome(tuple_expr(&expression, cursor, &mut graph, &mut context)),
expected,
);
}
}
#[test]
fn tuple_elements_preserve_left_to_right_source_stops() {
for (expression, expected) in [
("#(failed(\"first\"), failed(\"second\"))", "panic: first"),
("#(1, failed(\"second\"))", "panic: second"),
("#(panic as \"first\", panic as \"second\")", "panic: first"),
("#(1, panic as \"second\")", "panic: second"),
] {
assert_eq!(run(expression), expected);
}
}
fn run(expression: &str) -> String {
let source = format!(
r#"
fn failed(message: String) -> Int {{ panic as message }}
pub fn main() {{ {expression} }}
"#,
);
let typed = crate::compile_typed_module("main", "main.gleam", source.as_str())
.expect("source should compile");
let module = crate::plan_module(typed).expect("source should plan");
crate::run_main(
&crate::ExecutionPlan::from_module_plan(module),
&mut Vec::new(),
)
.unwrap_err()
.to_string()
}
}