Skip to content

feat: handle constant index operations on simple slices #3464

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
TomAFrench merged 3 commits into from
Nov 9, 2023
Merged

feat: handle constant index operations on simple slices #3464

Changes from all commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
3b798a5
feat: handle constant index operations on simple slices
TomAFrench Nov 9, 2023
c6b5d62
fix: account for slices inside arrays
TomAFrench Nov 9, 2023
ba0c6fa
Update compiler/noirc_evaluator/src/ssa/acir_gen/mod.rs
TomAFrench Nov 9, 2023
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
123 changes: 62 additions & 61 deletions compiler/noirc_evaluator/src/ssa/acir_gen/mod.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -658,75 +658,76 @@ impl Context {
store_value: Option<ValueId>,
) -> Result<bool, RuntimeError> {
let index_const = dfg.get_numeric_constant(index);
match dfg.type_of_value(array) {
Type::Array(_, _) => {
match self.convert_value(array, dfg) {
AcirValue::Var(acir_var, _) => {
return Err(RuntimeError::InternalError(InternalError::UnExpected {
expected: "an array value".to_string(),
found: format!("{acir_var:?}"),
call_stack: self.acir_context.get_call_stack(),
}))
}
AcirValue::Array(array) => {
if let Some(index_const) = index_const {
let array_size = array.len();
let index = match index_const.try_to_u64() {
Some(index_const) => index_const as usize,
None => {
let call_stack = self.acir_context.get_call_stack();
return Err(RuntimeError::TypeConversion {
from: "array index".to_string(),
into: "u64".to_string(),
call_stack,
});
let value_type = dfg.type_of_value(array);
let (Type::Array(element_types, _) | Type::Slice(element_types)) = &value_type else {
unreachable!("ICE: expected array or slice type");

};

// TODO(#3188): Need to be able to handle constant index for slices to seriously reduce
// constraint sizes of nested slices
// This can only be done if we accurately flatten nested slices as otherwise we will reach
// index out of bounds errors. If the slice is already flat then we can treat them similarly to arrays.
if matches!(value_type, Type::Slice(_))
&& element_types.iter().any(|element| element.contains_slice_element())
{
return Ok(false);
}

match self.convert_value(array, dfg) {
AcirValue::Var(acir_var, _) => {
return Err(RuntimeError::InternalError(InternalError::UnExpected {
expected: "an array value".to_string(),
found: format!("{acir_var:?}"),
call_stack: self.acir_context.get_call_stack(),
}))
}
AcirValue::Array(array) => {
if let Some(index_const) = index_const {
let array_size = array.len();
let index = match index_const.try_to_u64() {
Some(index_const) => index_const as usize,
None => {
let call_stack = self.acir_context.get_call_stack();
return Err(RuntimeError::TypeConversion {
from: "array index".to_string(),
into: "u64".to_string(),
call_stack,
});
}
};
if self.acir_context.is_constant_one(&self.current_side_effects_enabled_var) {
// Report the error if side effects are enabled.
if index >= array_size {
let call_stack = self.acir_context.get_call_stack();
return Err(RuntimeError::IndexOutOfBounds {
index,
array_size,
call_stack,
});
} else {
let value = match store_value {
Some(store_value) => {
let store_value = self.convert_value(store_value, dfg);
AcirValue::Array(array.update(index, store_value))
}
None => array[index].clone(),
};
if self
.acir_context
.is_constant_one(&self.current_side_effects_enabled_var)
{
// Report the error if side effects are enabled.
if index >= array_size {
let call_stack = self.acir_context.get_call_stack();
return Err(RuntimeError::IndexOutOfBounds {
index,
array_size,
call_stack,
});
} else {
let value = match store_value {
Some(store_value) => {
let store_value = self.convert_value(store_value, dfg);
AcirValue::Array(array.update(index, store_value))
}
None => array[index].clone(),
};

self.define_result(dfg, instruction, value);
return Ok(true);
}
}
// If there is a predicate and the index is not out of range, we can directly perform the read
else if index < array_size && store_value.is_none() {
self.define_result(dfg, instruction, array[index].clone());
return Ok(true);
}
self.define_result(dfg, instruction, value);
return Ok(true);
}
}
AcirValue::DynamicArray(_) => (),
// If there is a predicate and the index is not out of range, we can directly perform the read
else if index < array_size && store_value.is_none() {
self.define_result(dfg, instruction, array[index].clone());
return Ok(true);
}
}
}
Type::Slice(_) => {
// TODO(#3188): Need to be able to handle constant index for slices to seriously reduce
// constraint sizes of nested slices
// This can only be done if we accurately flatten nested slices as other we will reach
// index out of bounds errors.
AcirValue::DynamicArray(_) => (),
};

// Do nothing we only want dynamic checks for slices
}
_ => unreachable!("ICE: expected array or slice type"),
}
Ok(false)
}

Expand Down