Source code
Revision control
Copy as Markdown
Other Tools
/*!
Backend for [SPIR-V][spv] (Standard Portable Intermediate Representation).
*/
mod block;
mod helpers;
mod image;
mod index;
mod instructions;
mod layout;
mod ray;
mod recyclable;
mod selection;
mod subgroup;
mod writer;
pub use spirv::{Capability, SourceLanguage};
use crate::arena::{Handle, HandleVec};
use crate::proc::{BoundsCheckPolicies, TypeResolution};
use spirv::Word;
use std::ops;
use thiserror::Error;
#[derive(Clone)]
struct PhysicalLayout {
magic_number: Word,
version: Word,
generator: Word,
bound: Word,
instruction_schema: Word,
}
#[derive(Default)]
struct LogicalLayout {
capabilities: Vec<Word>,
extensions: Vec<Word>,
ext_inst_imports: Vec<Word>,
memory_model: Vec<Word>,
entry_points: Vec<Word>,
execution_modes: Vec<Word>,
debugs: Vec<Word>,
annotations: Vec<Word>,
declarations: Vec<Word>,
function_declarations: Vec<Word>,
function_definitions: Vec<Word>,
}
struct Instruction {
op: spirv::Op,
wc: u32,
type_id: Option<Word>,
result_id: Option<Word>,
operands: Vec<Word>,
}
const BITS_PER_BYTE: crate::Bytes = 8;
#[derive(Clone, Debug, Error)]
pub enum Error {
#[error("The requested entry point couldn't be found")]
EntryPointNotFound,
#[error("target SPIRV-{0}.{1} is not supported")]
UnsupportedVersion(u8, u8),
#[error("using {0} requires at least one of the capabilities {1:?}, but none are available")]
MissingCapabilities(&'static str, Vec<Capability>),
#[error("unimplemented {0}")]
FeatureNotImplemented(&'static str),
#[error("module is not validated properly: {0}")]
Validation(&'static str),
#[error("overrides should not be present at this stage")]
Override,
}
#[derive(Default)]
struct IdGenerator(Word);
impl IdGenerator {
fn next(&mut self) -> Word {
self.0 += 1;
self.0
}
}
#[derive(Debug, Clone)]
pub struct DebugInfo<'a> {
pub source_code: &'a str,
pub file_name: &'a std::path::Path,
pub language: SourceLanguage,
}
/// A SPIR-V block to which we are still adding instructions.
///
/// A `Block` represents a SPIR-V block that does not yet have a termination
/// instruction like `OpBranch` or `OpReturn`.
///
/// The `OpLabel` that starts the block is implicit. It will be emitted based on
/// `label_id` when we write the block to a `LogicalLayout`.
///
/// To terminate a `Block`, pass the block and the termination instruction to
/// `Function::consume`. This takes ownership of the `Block` and transforms it
/// into a `TerminatedBlock`.
struct Block {
label_id: Word,
body: Vec<Instruction>,
}
/// A SPIR-V block that ends with a termination instruction.
struct TerminatedBlock {
label_id: Word,
body: Vec<Instruction>,
}
impl Block {
const fn new(label_id: Word) -> Self {
Block {
label_id,
body: Vec::new(),
}
}
}
struct LocalVariable {
id: Word,
instruction: Instruction,
}
struct ResultMember {
id: Word,
type_id: Word,
built_in: Option<crate::BuiltIn>,
}
struct EntryPointContext {
argument_ids: Vec<Word>,
results: Vec<ResultMember>,
}
#[derive(Default)]
struct Function {
signature: Option<Instruction>,
parameters: Vec<FunctionArgument>,
variables: crate::FastHashMap<Handle<crate::LocalVariable>, LocalVariable>,
/// A map taking an expression that yields a composite value (array, matrix)
/// to the temporary variables we have spilled it to, if any. Spilling
/// allows us to render an arbitrary chain of [`Access`] and [`AccessIndex`]
/// expressions as an `OpAccessChain` and an `OpLoad` (plus bounds checks).
/// This supports dynamic indexing of by-value arrays and matrices, which
/// SPIR-V does not.
///
/// [`Access`]: crate::Expression::Access
/// [`AccessIndex`]: crate::Expression::AccessIndex
spilled_composites: crate::FastIndexMap<Handle<crate::Expression>, LocalVariable>,
/// A set of expressions that are either in [`spilled_composites`] or refer
/// to some component/element of such.
///
/// [`spilled_composites`]: Function::spilled_composites
spilled_accesses: crate::arena::HandleSet<crate::Expression>,
/// A map taking each expression to the number of [`Access`] and
/// [`AccessIndex`] expressions that uses it as a base value. If an
/// expression has no entry, its count is zero: it is never used as a
/// [`Access`] or [`AccessIndex`] base.
///
/// We use this, together with [`ExpressionInfo::ref_count`], to recognize
/// the tips of chains of [`Access`] and [`AccessIndex`] expressions that
/// access spilled values --- expressions in [`spilled_composites`]. We
/// defer generating code for the chain until we reach its tip, so we can
/// handle it with a single instruction.
///
/// [`Access`]: crate::Expression::Access
/// [`AccessIndex`]: crate::Expression::AccessIndex
/// [`ExpressionInfo::ref_count`]: crate::valid::ExpressionInfo
/// [`spilled_composites`]: Function::spilled_composites
access_uses: crate::FastHashMap<Handle<crate::Expression>, usize>,
blocks: Vec<TerminatedBlock>,
entry_point_context: Option<EntryPointContext>,
}
impl Function {
fn consume(&mut self, mut block: Block, termination: Instruction) {
block.body.push(termination);
self.blocks.push(TerminatedBlock {
label_id: block.label_id,
body: block.body,
})
}
fn parameter_id(&self, index: u32) -> Word {
match self.entry_point_context {
Some(ref context) => context.argument_ids[index as usize],
None => self.parameters[index as usize]
.instruction
.result_id
.unwrap(),
}
}
}
/// Characteristics of a SPIR-V `OpTypeImage` type.
///
/// SPIR-V requires non-composite types to be unique, including images. Since we
/// use `LocalType` for this deduplication, it's essential that `LocalImageType`
/// be equal whenever the corresponding `OpTypeImage`s would be. To reduce the
/// likelihood of mistakes, we use fields that correspond exactly to the
/// operands of an `OpTypeImage` instruction, using the actual SPIR-V types
/// where practical.
#[derive(Debug, PartialEq, Hash, Eq, Copy, Clone)]
struct LocalImageType {
sampled_type: crate::Scalar,
dim: spirv::Dim,
flags: ImageTypeFlags,
image_format: spirv::ImageFormat,
}
bitflags::bitflags! {
/// Flags corresponding to the boolean(-ish) parameters to OpTypeImage.
#[derive(Clone, Copy, Debug, Eq, Hash, PartialEq)]
pub struct ImageTypeFlags: u8 {
const DEPTH = 0x1;
const ARRAYED = 0x2;
const MULTISAMPLED = 0x4;
const SAMPLED = 0x8;
}
}
impl LocalImageType {
/// Construct a `LocalImageType` from the fields of a `TypeInner::Image`.
fn from_inner(dim: crate::ImageDimension, arrayed: bool, class: crate::ImageClass) -> Self {
let make_flags = |multi: bool, other: ImageTypeFlags| -> ImageTypeFlags {
let mut flags = other;
flags.set(ImageTypeFlags::ARRAYED, arrayed);
flags.set(ImageTypeFlags::MULTISAMPLED, multi);
flags
};
let dim = spirv::Dim::from(dim);
match class {
crate::ImageClass::Sampled { kind, multi } => LocalImageType {
sampled_type: crate::Scalar { kind, width: 4 },
dim,
flags: make_flags(multi, ImageTypeFlags::SAMPLED),
image_format: spirv::ImageFormat::Unknown,
},
crate::ImageClass::Depth { multi } => LocalImageType {
sampled_type: crate::Scalar {
kind: crate::ScalarKind::Float,
width: 4,
},
dim,
flags: make_flags(multi, ImageTypeFlags::DEPTH | ImageTypeFlags::SAMPLED),
image_format: spirv::ImageFormat::Unknown,
},
crate::ImageClass::Storage { format, access: _ } => LocalImageType {
sampled_type: format.into(),
dim,
flags: make_flags(false, ImageTypeFlags::empty()),
image_format: format.into(),
},
}
}
}
/// A numeric type, for use in [`LocalType`].
#[derive(Debug, PartialEq, Hash, Eq, Copy, Clone)]
enum NumericType {
Scalar(crate::Scalar),
Vector {
size: crate::VectorSize,
scalar: crate::Scalar,
},
Matrix {
columns: crate::VectorSize,
rows: crate::VectorSize,
scalar: crate::Scalar,
},
}
impl NumericType {
const fn from_inner(inner: &crate::TypeInner) -> Option<Self> {
match *inner {
crate::TypeInner::Scalar(scalar) | crate::TypeInner::Atomic(scalar) => {
Some(NumericType::Scalar(scalar))
}
crate::TypeInner::Vector { size, scalar } => Some(NumericType::Vector { size, scalar }),
crate::TypeInner::Matrix {
columns,
rows,
scalar,
} => Some(NumericType::Matrix {
columns,
rows,
scalar,
}),
_ => None,
}
}
}
/// A SPIR-V type constructed during code generation.
///
/// This is the variant of [`LookupType`] used to represent types that might not
/// be available in the arena. Variants are present here for one of two reasons:
///
/// - They represent types synthesized during code generation, as explained
/// in the documentation for [`LookupType`].
///
/// - They represent types for which SPIR-V forbids duplicate `OpType...`
/// instructions, requiring deduplication.
///
/// This is not a complete copy of [`TypeInner`]: for example, SPIR-V generation
/// never synthesizes new struct types, so `LocalType` has nothing for that.
///
/// Each `LocalType` variant should be handled identically to its analogous
/// `TypeInner` variant. You can use the [`LocalType::from_inner`] function to
/// help with this, by converting everything possible to a `LocalType` before
/// inspecting it.
///
/// ## `LocalType` equality and SPIR-V `OpType` uniqueness
///
/// The definition of `Eq` on `LocalType` is carefully chosen to help us follow
/// certain SPIR-V rules. SPIR-V §2.8 requires some classes of `OpType...`
/// instructions to be unique; for example, you can't have two `OpTypeInt 32 1`
/// instructions in the same module. All 32-bit signed integers must use the
/// same type id.
///
/// All SPIR-V types that must be unique can be represented as a `LocalType`,
/// and two `LocalType`s are always `Eq` if SPIR-V would require them to use the
/// same `OpType...` instruction. This lets us avoid duplicates by recording the
/// ids of the type instructions we've already generated in a hash table,
/// [`Writer::lookup_type`], keyed by `LocalType`.
///
/// As another example, [`LocalImageType`], stored in the `LocalType::Image`
/// variant, is designed to help us deduplicate `OpTypeImage` instructions. See
/// its documentation for details.
///
/// `LocalType` also includes variants like `Pointer` that do not need to be
/// unique - but it is harmless to avoid the duplication.
///
/// As it always must, the `Hash` implementation respects the `Eq` relation.
///
/// [`TypeInner`]: crate::TypeInner
#[derive(Debug, PartialEq, Hash, Eq, Copy, Clone)]
enum LocalType {
/// A numeric type.
Numeric(NumericType),
LocalPointer {
base: NumericType,
class: spirv::StorageClass,
},
Pointer {
base: Handle<crate::Type>,
class: spirv::StorageClass,
},
Image(LocalImageType),
SampledImage {
image_type_id: Word,
},
Sampler,
/// Equivalent to a [`LocalType::Pointer`] whose `base` is a Naga IR [`BindingArray`]. SPIR-V
/// permits duplicated `OpTypePointer` ids, so it's fine to have two different [`LocalType`]
/// representations for pointer types.
///
/// [`BindingArray`]: crate::TypeInner::BindingArray
PointerToBindingArray {
base: Handle<crate::Type>,
size: u32,
space: crate::AddressSpace,
},
BindingArray {
base: Handle<crate::Type>,
size: u32,
},
AccelerationStructure,
RayQuery,
}
/// A type encountered during SPIR-V generation.
///
/// In the process of writing SPIR-V, we need to synthesize various types for
/// intermediate results and such: pointer types, vector/matrix component types,
/// or even booleans, which usually appear in SPIR-V code even when they're not
/// used by the module source.
///
/// However, we can't use `crate::Type` or `crate::TypeInner` for these, as the
/// type arena may not contain what we need (it only contains types used
/// directly by other parts of the IR), and the IR module is immutable, so we
/// can't add anything to it.
///
/// So for local use in the SPIR-V writer, we use this type, which holds either
/// a handle into the arena, or a [`LocalType`] containing something synthesized
/// locally.
///
/// This is very similar to the [`proc::TypeResolution`] enum, with `LocalType`
/// playing the role of `TypeInner`. However, `LocalType` also has other
/// properties needed for SPIR-V generation; see the description of
/// [`LocalType`] for details.
///
/// [`proc::TypeResolution`]: crate::proc::TypeResolution
#[derive(Debug, PartialEq, Hash, Eq, Copy, Clone)]
enum LookupType {
Handle(Handle<crate::Type>),
Local(LocalType),
}
impl From<LocalType> for LookupType {
fn from(local: LocalType) -> Self {
Self::Local(local)
}
}
#[derive(Debug, PartialEq, Clone, Hash, Eq)]
struct LookupFunctionType {
parameter_type_ids: Vec<Word>,
return_type_id: Word,
}
impl LocalType {
fn from_inner(inner: &crate::TypeInner) -> Option<Self> {
Some(match *inner {
crate::TypeInner::Scalar(_)
| crate::TypeInner::Atomic(_)
| crate::TypeInner::Vector { .. }
| crate::TypeInner::Matrix { .. } => {
// We expect `NumericType::from_inner` to handle all
// these cases, so unwrap.
LocalType::Numeric(NumericType::from_inner(inner).unwrap())
}
crate::TypeInner::Pointer { base, space } => LocalType::Pointer {
base,
class: helpers::map_storage_class(space),
},
crate::TypeInner::ValuePointer {
size: Some(size),
scalar,
space,
} => LocalType::LocalPointer {
base: NumericType::Vector { size, scalar },
class: helpers::map_storage_class(space),
},
crate::TypeInner::ValuePointer {
size: None,
scalar,
space,
} => LocalType::LocalPointer {
base: NumericType::Scalar(scalar),
class: helpers::map_storage_class(space),
},
crate::TypeInner::Image {
dim,
arrayed,
class,
} => LocalType::Image(LocalImageType::from_inner(dim, arrayed, class)),
crate::TypeInner::Sampler { comparison: _ } => LocalType::Sampler,
crate::TypeInner::AccelerationStructure => LocalType::AccelerationStructure,
crate::TypeInner::RayQuery => LocalType::RayQuery,
crate::TypeInner::Array { .. }
| crate::TypeInner::Struct { .. }
| crate::TypeInner::BindingArray { .. } => return None,
})
}
}
#[derive(Debug)]
enum Dimension {
Scalar,
Vector,
Matrix,
}
/// A map from evaluated [`Expression`](crate::Expression)s to their SPIR-V ids.
///
/// When we emit code to evaluate a given `Expression`, we record the
/// SPIR-V id of its value here, under its `Handle<Expression>` index.
///
/// A `CachedExpressions` value can be indexed by a `Handle<Expression>` value.
///
/// [emit]: index.html#expression-evaluation-time-and-scope
#[derive(Default)]
struct CachedExpressions {
ids: HandleVec<crate::Expression, Word>,
}
impl CachedExpressions {
fn reset(&mut self, length: usize) {
self.ids.clear();
self.ids.resize(length, 0);
}
}
impl ops::Index<Handle<crate::Expression>> for CachedExpressions {
type Output = Word;
fn index(&self, h: Handle<crate::Expression>) -> &Word {
let id = &self.ids[h];
if *id == 0 {
unreachable!("Expression {:?} is not cached!", h);
}
id
}
}
impl ops::IndexMut<Handle<crate::Expression>> for CachedExpressions {
fn index_mut(&mut self, h: Handle<crate::Expression>) -> &mut Word {
let id = &mut self.ids[h];
if *id != 0 {
unreachable!("Expression {:?} is already cached!", h);
}
id
}
}
impl recyclable::Recyclable for CachedExpressions {
fn recycle(self) -> Self {
CachedExpressions {
ids: self.ids.recycle(),
}
}
}
#[derive(Eq, Hash, PartialEq)]
enum CachedConstant {
Literal(crate::proc::HashableLiteral),
Composite {
ty: LookupType,
constituent_ids: Vec<Word>,
},
ZeroValue(Word),
}
/// The SPIR-V representation of a [`crate::GlobalVariable`].
///
/// In the Vulkan spec 1.3.296, the section [Descriptor Set Interface][dsi] says:
///
/// > Variables identified with the `Uniform` storage class are used to access
/// > transparent buffer backed resources. Such variables *must* be:
/// >
/// > - typed as `OpTypeStruct`, or an array of this type,
/// >
/// > - identified with a `Block` or `BufferBlock` decoration, and
/// >
/// > - laid out explicitly using the `Offset`, `ArrayStride`, and `MatrixStride`
/// > decorations as specified in "Offset and Stride Assignment".
///
/// This is followed by identical language for the `StorageBuffer`,
/// except that a `BufferBlock` decoration is not allowed.
///
/// When we encounter a global variable in the [`Storage`] or [`Uniform`]
/// address spaces whose type is not already [`Struct`], this backend implicitly
/// wraps the global variable in a struct: we generate a SPIR-V global variable
/// holding an `OpTypeStruct` with a single member, whose type is what the Naga
/// global's type would suggest, decorated as required above.
///
/// The [`helpers::global_needs_wrapper`] function determines whether a given
/// [`crate::GlobalVariable`] needs to be wrapped.
///
/// [`Storage`]: crate::AddressSpace::Storage
/// [`Uniform`]: crate::AddressSpace::Uniform
/// [`Struct`]: crate::TypeInner::Struct
#[derive(Clone)]
struct GlobalVariable {
/// The SPIR-V id of the `OpVariable` that declares the global.
///
/// If this global has been implicitly wrapped in an `OpTypeStruct`, this id
/// refers to the wrapper, not the original Naga value it contains. If you
/// need the Naga value, use [`access_id`] instead of this field.
///
/// If this global is not implicitly wrapped, this is the same as
/// [`access_id`].
///
/// This is used to compute the `access_id` pointer in function prologues,
/// and used for `ArrayLength` expressions, which need to pass the wrapper
/// struct.
///
/// [`access_id`]: GlobalVariable::access_id
var_id: Word,
/// The loaded value of a `AddressSpace::Handle` global variable.
///
/// If the current function uses this global variable, this is the id of an
/// `OpLoad` instruction in the function's prologue that loads its value.
/// (This value is assigned as we write the prologue code of each function.)
/// It is then used for all operations on the global, such as `OpImageSample`.
handle_id: Word,
/// The SPIR-V id of a pointer to this variable's Naga IR value.
///
/// If the current function uses this global variable, and it has been
/// implicitly wrapped in an `OpTypeStruct`, this is the id of an
/// `OpAccessChain` instruction in the function's prologue that refers to
/// the wrapped value inside the struct. (This value is assigned as we write
/// the prologue code of each function.) If you need the wrapper struct
/// itself, use [`var_id`] instead of this field.
///
/// If this global is not implicitly wrapped, this is the same as
/// [`var_id`].
///
/// [`var_id`]: GlobalVariable::var_id
access_id: Word,
}
impl GlobalVariable {
const fn dummy() -> Self {
Self {
var_id: 0,
handle_id: 0,
access_id: 0,
}
}
const fn new(id: Word) -> Self {
Self {
var_id: id,
handle_id: 0,
access_id: 0,
}
}
/// Prepare `self` for use within a single function.
fn reset_for_function(&mut self) {
self.handle_id = 0;
self.access_id = 0;
}
}
struct FunctionArgument {
/// Actual instruction of the argument.
instruction: Instruction,
handle_id: Word,
}
/// Tracks the expressions for which the backend emits the following instructions:
/// - OpConstantTrue
/// - OpConstantFalse
/// - OpConstant
/// - OpConstantComposite
/// - OpConstantNull
struct ExpressionConstnessTracker {
inner: crate::arena::HandleSet<crate::Expression>,
}
impl ExpressionConstnessTracker {
fn from_arena(arena: &crate::Arena<crate::Expression>) -> Self {
let mut inner = crate::arena::HandleSet::for_arena(arena);
for (handle, expr) in arena.iter() {
let insert = match *expr {
crate::Expression::Literal(_)
| crate::Expression::ZeroValue(_)
| crate::Expression::Constant(_) => true,
crate::Expression::Compose { ref components, .. } => {
components.iter().all(|&h| inner.contains(h))
}
crate::Expression::Splat { value, .. } => inner.contains(value),
_ => false,
};
if insert {
inner.insert(handle);
}
}
Self { inner }
}
fn is_const(&self, value: Handle<crate::Expression>) -> bool {
self.inner.contains(value)
}
}
/// General information needed to emit SPIR-V for Naga statements.
struct BlockContext<'w> {
/// The writer handling the module to which this code belongs.
writer: &'w mut Writer,
/// The [`Module`](crate::Module) for which we're generating code.
ir_module: &'w crate::Module,
/// The [`Function`](crate::Function) for which we're generating code.
ir_function: &'w crate::Function,
/// Information module validation produced about
/// [`ir_function`](BlockContext::ir_function).
fun_info: &'w crate::valid::FunctionInfo,
/// The [`spv::Function`](Function) to which we are contributing SPIR-V instructions.
function: &'w mut Function,
/// SPIR-V ids for expressions we've evaluated.
cached: CachedExpressions,
/// The `Writer`'s temporary vector, for convenience.
temp_list: Vec<Word>,
/// Tracks the constness of `Expression`s residing in `self.ir_function.expressions`
expression_constness: ExpressionConstnessTracker,
}
impl BlockContext<'_> {
fn gen_id(&mut self) -> Word {
self.writer.id_gen.next()
}
fn get_type_id(&mut self, lookup_type: LookupType) -> Word {
self.writer.get_type_id(lookup_type)
}
fn get_expression_type_id(&mut self, tr: &TypeResolution) -> Word {
self.writer.get_expression_type_id(tr)
}
fn get_index_constant(&mut self, index: Word) -> Word {
self.writer.get_constant_scalar(crate::Literal::U32(index))
}
fn get_scope_constant(&mut self, scope: Word) -> Word {
self.writer
.get_constant_scalar(crate::Literal::I32(scope as _))
}
fn get_pointer_id(&mut self, handle: Handle<crate::Type>, class: spirv::StorageClass) -> Word {
self.writer.get_pointer_id(handle, class)
}
}
pub struct Writer {
physical_layout: PhysicalLayout,
logical_layout: LogicalLayout,
id_gen: IdGenerator,
/// The set of capabilities modules are permitted to use.
///
/// This is initialized from `Options::capabilities`.
capabilities_available: Option<crate::FastHashSet<Capability>>,
/// The set of capabilities used by this module.
///
/// If `capabilities_available` is `Some`, then this is always a subset of
/// that.
capabilities_used: crate::FastIndexSet<Capability>,
/// The set of spirv extensions used.
extensions_used: crate::FastIndexSet<&'static str>,
debugs: Vec<Instruction>,
annotations: Vec<Instruction>,
flags: WriterFlags,
bounds_check_policies: BoundsCheckPolicies,
zero_initialize_workgroup_memory: ZeroInitializeWorkgroupMemoryMode,
void_type: Word,
//TODO: convert most of these into vectors, addressable by handle indices
lookup_type: crate::FastHashMap<LookupType, Word>,
lookup_function: crate::FastHashMap<Handle<crate::Function>, Word>,
lookup_function_type: crate::FastHashMap<LookupFunctionType, Word>,
/// Indexed by const-expression handle indexes
constant_ids: HandleVec<crate::Expression, Word>,
cached_constants: crate::FastHashMap<CachedConstant, Word>,
global_variables: HandleVec<crate::GlobalVariable, GlobalVariable>,
binding_map: BindingMap,
// Cached expressions are only meaningful within a BlockContext, but we
// retain the table here between functions to save heap allocations.
saved_cached: CachedExpressions,
gl450_ext_inst_id: Word,
// Just a temporary list of SPIR-V ids
temp_list: Vec<Word>,
}
bitflags::bitflags! {
#[derive(Clone, Copy, Debug, Eq, PartialEq)]
pub struct WriterFlags: u32 {
/// Include debug labels for everything.
const DEBUG = 0x1;
/// Flip Y coordinate of [`BuiltIn::Position`] output.
///
/// [`BuiltIn::Position`]: crate::BuiltIn::Position
const ADJUST_COORDINATE_SPACE = 0x2;
/// Emit [`OpName`][op] for input/output locations.
///
/// Contrary to spec, some drivers treat it as semantic, not allowing
/// any conflicts.
///
const LABEL_VARYINGS = 0x4;
/// Emit [`PointSize`] output builtin to vertex shaders, which is
/// required for drawing with `PointList` topology.
///
/// [`PointSize`]: crate::BuiltIn::PointSize
const FORCE_POINT_SIZE = 0x8;
/// Clamp [`BuiltIn::FragDepth`] output between 0 and 1.
///
/// [`BuiltIn::FragDepth`]: crate::BuiltIn::FragDepth
const CLAMP_FRAG_DEPTH = 0x10;
}
}
#[derive(Clone, Debug, Default, PartialEq, Eq, Hash)]
#[cfg_attr(feature = "serialize", derive(serde::Serialize))]
#[cfg_attr(feature = "deserialize", derive(serde::Deserialize))]
pub struct BindingInfo {
/// If the binding is an unsized binding array, this overrides the size.
pub binding_array_size: Option<u32>,
}
// Using `BTreeMap` instead of `HashMap` so that we can hash itself.
pub type BindingMap = std::collections::BTreeMap<crate::ResourceBinding, BindingInfo>;
#[derive(Clone, Copy, Debug, PartialEq, Eq)]
pub enum ZeroInitializeWorkgroupMemoryMode {
/// Via `VK_KHR_zero_initialize_workgroup_memory` or Vulkan 1.3
Native,
/// Via assignments + barrier
Polyfill,
None,
}
#[derive(Debug, Clone)]
pub struct Options<'a> {
/// (Major, Minor) target version of the SPIR-V.
pub lang_version: (u8, u8),
/// Configuration flags for the writer.
pub flags: WriterFlags,
/// Map of resources to information about the binding.
pub binding_map: BindingMap,
/// If given, the set of capabilities modules are allowed to use. Code that
/// requires capabilities beyond these is rejected with an error.
///
/// If this is `None`, all capabilities are permitted.
pub capabilities: Option<crate::FastHashSet<Capability>>,
/// How should generate code handle array, vector, matrix, or image texel
/// indices that are out of range?
pub bounds_check_policies: BoundsCheckPolicies,
/// Dictates the way workgroup variables should be zero initialized
pub zero_initialize_workgroup_memory: ZeroInitializeWorkgroupMemoryMode,
pub debug_info: Option<DebugInfo<'a>>,
}
impl<'a> Default for Options<'a> {
fn default() -> Self {
let mut flags = WriterFlags::ADJUST_COORDINATE_SPACE
| WriterFlags::LABEL_VARYINGS
| WriterFlags::CLAMP_FRAG_DEPTH;
if cfg!(debug_assertions) {
flags |= WriterFlags::DEBUG;
}
Options {
lang_version: (1, 0),
flags,
binding_map: BindingMap::default(),
capabilities: None,
bounds_check_policies: BoundsCheckPolicies::default(),
zero_initialize_workgroup_memory: ZeroInitializeWorkgroupMemoryMode::Polyfill,
debug_info: None,
}
}
}
// A subset of options meant to be changed per pipeline.
#[derive(Debug, Clone)]
#[cfg_attr(feature = "serialize", derive(serde::Serialize))]
#[cfg_attr(feature = "deserialize", derive(serde::Deserialize))]
pub struct PipelineOptions {
/// The stage of the entry point.
pub shader_stage: crate::ShaderStage,
/// The name of the entry point.
///
/// If no entry point that matches is found while creating a [`Writer`], a error will be thrown.
pub entry_point: String,
}
pub fn write_vec(
module: &crate::Module,
info: &crate::valid::ModuleInfo,
options: &Options,
pipeline_options: Option<&PipelineOptions>,
) -> Result<Vec<u32>, Error> {
let mut words: Vec<u32> = Vec::new();
let mut w = Writer::new(options)?;
w.write(
module,
info,
pipeline_options,
&options.debug_info,
&mut words,
)?;
Ok(words)
}