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/*!
This module provides functionality for polyfilling `f16` input/output variables
when the `StorageInputOutput16` capability is not available or disabled.
It works by:
1. Declaring `f16` I/O variables as `f32` in SPIR-V
2. Converting between `f16` and `f32` at runtime using `OpFConvert`
3. Maintaining mappings to track which variables need conversion
*/
use crate::back::spv::{Instruction, LocalType, NumericType, Word};
use alloc::vec::Vec;
/// Manages `f16` I/O polyfill state and operations.
#[derive(Default)]
pub(in crate::back::spv) struct F16IoPolyfill {
use_native: bool,
io_var_to_f32_type: crate::FastHashMap<Word, Word>,
}
impl F16IoPolyfill {
pub fn new(use_storage_input_output_16: bool) -> Self {
Self {
use_native: use_storage_input_output_16,
io_var_to_f32_type: crate::FastHashMap::default(),
}
}
pub fn needs_polyfill(&self, ty_inner: &crate::TypeInner) -> bool {
use crate::{ScalarKind as Sk, TypeInner};
!self.use_native
&& match *ty_inner {
TypeInner::Scalar(ref s) if s.kind == Sk::Float && s.width == 2 => true,
TypeInner::Vector { scalar, .. }
if scalar.kind == Sk::Float && scalar.width == 2 =>
{
true
}
_ => false,
}
}
pub fn register_io_var(&mut self, variable_id: Word, f32_type_id: Word) {
self.io_var_to_f32_type.insert(variable_id, f32_type_id);
}
pub fn get_f32_io_type(&self, variable_id: Word) -> Option<Word> {
self.io_var_to_f32_type.get(&variable_id).copied()
}
pub fn emit_f16_to_f32_conversion(
f16_value_id: Word,
f32_type_id: Word,
converted_id: Word,
body: &mut Vec<Instruction>,
) {
body.push(Instruction::unary(
spirv::Op::FConvert,
f32_type_id,
converted_id,
f16_value_id,
));
}
pub fn emit_f32_to_f16_conversion(
f32_value_id: Word,
f16_type_id: Word,
converted_id: Word,
body: &mut Vec<Instruction>,
) {
body.push(Instruction::unary(
spirv::Op::FConvert,
f16_type_id,
converted_id,
f32_value_id,
));
}
pub fn create_polyfill_type(ty_inner: &crate::TypeInner) -> Option<LocalType> {
use crate::{ScalarKind as Sk, TypeInner};
match *ty_inner {
TypeInner::Scalar(ref s) if s.kind == Sk::Float && s.width == 2 => {
Some(LocalType::Numeric(NumericType::Scalar(crate::Scalar::F32)))
}
TypeInner::Vector { size, scalar } if scalar.kind == Sk::Float && scalar.width == 2 => {
Some(LocalType::Numeric(NumericType::Vector {
size,
scalar: crate::Scalar::F32,
}))
}
_ => None,
}
}
}
impl crate::back::spv::recyclable::Recyclable for F16IoPolyfill {
fn recycle(mut self) -> Self {
self.io_var_to_f32_type = self.io_var_to_f32_type.recycle();
self
}
}