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-rw-r--r--third_party/rust/naga/src/front/spv/function.rs674
1 files changed, 674 insertions, 0 deletions
diff --git a/third_party/rust/naga/src/front/spv/function.rs b/third_party/rust/naga/src/front/spv/function.rs
new file mode 100644
index 0000000000..198d9c52dd
--- /dev/null
+++ b/third_party/rust/naga/src/front/spv/function.rs
@@ -0,0 +1,674 @@
+use crate::{
+ arena::{Arena, Handle},
+ front::spv::{BlockContext, BodyIndex},
+};
+
+use super::{Error, Instruction, LookupExpression, LookupHelper as _};
+use crate::proc::Emitter;
+
+pub type BlockId = u32;
+
+#[derive(Copy, Clone, Debug)]
+pub struct MergeInstruction {
+ pub merge_block_id: BlockId,
+ pub continue_block_id: Option<BlockId>,
+}
+
+impl<I: Iterator<Item = u32>> super::Frontend<I> {
+ // Registers a function call. It will generate a dummy handle to call, which
+ // gets resolved after all the functions are processed.
+ pub(super) fn add_call(
+ &mut self,
+ from: spirv::Word,
+ to: spirv::Word,
+ ) -> Handle<crate::Function> {
+ let dummy_handle = self
+ .dummy_functions
+ .append(crate::Function::default(), Default::default());
+ self.deferred_function_calls.push(to);
+ self.function_call_graph.add_edge(from, to, ());
+ dummy_handle
+ }
+
+ pub(super) fn parse_function(&mut self, module: &mut crate::Module) -> Result<(), Error> {
+ let start = self.data_offset;
+ self.lookup_expression.clear();
+ self.lookup_load_override.clear();
+ self.lookup_sampled_image.clear();
+
+ let result_type_id = self.next()?;
+ let fun_id = self.next()?;
+ let _fun_control = self.next()?;
+ let fun_type_id = self.next()?;
+
+ let mut fun = {
+ let ft = self.lookup_function_type.lookup(fun_type_id)?;
+ if ft.return_type_id != result_type_id {
+ return Err(Error::WrongFunctionResultType(result_type_id));
+ }
+ crate::Function {
+ name: self.future_decor.remove(&fun_id).and_then(|dec| dec.name),
+ arguments: Vec::with_capacity(ft.parameter_type_ids.len()),
+ result: if self.lookup_void_type == Some(result_type_id) {
+ None
+ } else {
+ let lookup_result_ty = self.lookup_type.lookup(result_type_id)?;
+ Some(crate::FunctionResult {
+ ty: lookup_result_ty.handle,
+ binding: None,
+ })
+ },
+ local_variables: Arena::new(),
+ expressions: self
+ .make_expression_storage(&module.global_variables, &module.constants),
+ named_expressions: crate::NamedExpressions::default(),
+ body: crate::Block::new(),
+ }
+ };
+
+ // read parameters
+ for i in 0..fun.arguments.capacity() {
+ let start = self.data_offset;
+ match self.next_inst()? {
+ Instruction {
+ op: spirv::Op::FunctionParameter,
+ wc: 3,
+ } => {
+ let type_id = self.next()?;
+ let id = self.next()?;
+ let handle = fun.expressions.append(
+ crate::Expression::FunctionArgument(i as u32),
+ self.span_from(start),
+ );
+ self.lookup_expression.insert(
+ id,
+ LookupExpression {
+ handle,
+ type_id,
+ // Setting this to an invalid id will cause get_expr_handle
+ // to default to the main body making sure no load/stores
+ // are added.
+ block_id: 0,
+ },
+ );
+ //Note: we redo the lookup in order to work around `self` borrowing
+
+ if type_id
+ != self
+ .lookup_function_type
+ .lookup(fun_type_id)?
+ .parameter_type_ids[i]
+ {
+ return Err(Error::WrongFunctionArgumentType(type_id));
+ }
+ let ty = self.lookup_type.lookup(type_id)?.handle;
+ let decor = self.future_decor.remove(&id).unwrap_or_default();
+ fun.arguments.push(crate::FunctionArgument {
+ name: decor.name,
+ ty,
+ binding: None,
+ });
+ }
+ Instruction { op, .. } => return Err(Error::InvalidParameter(op)),
+ }
+ }
+
+ // Read body
+ self.function_call_graph.add_node(fun_id);
+ let mut parameters_sampling =
+ vec![super::image::SamplingFlags::empty(); fun.arguments.len()];
+
+ let mut block_ctx = BlockContext {
+ phis: Default::default(),
+ blocks: Default::default(),
+ body_for_label: Default::default(),
+ mergers: Default::default(),
+ bodies: Default::default(),
+ function_id: fun_id,
+ expressions: &mut fun.expressions,
+ local_arena: &mut fun.local_variables,
+ const_arena: &mut module.constants,
+ const_expressions: &mut module.const_expressions,
+ type_arena: &module.types,
+ global_arena: &module.global_variables,
+ arguments: &fun.arguments,
+ parameter_sampling: &mut parameters_sampling,
+ };
+ // Insert the main body whose parent is also himself
+ block_ctx.bodies.push(super::Body::with_parent(0));
+
+ // Scan the blocks and add them as nodes
+ loop {
+ let fun_inst = self.next_inst()?;
+ log::debug!("{:?}", fun_inst.op);
+ match fun_inst.op {
+ spirv::Op::Line => {
+ fun_inst.expect(4)?;
+ let _file_id = self.next()?;
+ let _row_id = self.next()?;
+ let _col_id = self.next()?;
+ }
+ spirv::Op::Label => {
+ // Read the label ID
+ fun_inst.expect(2)?;
+ let block_id = self.next()?;
+
+ self.next_block(block_id, &mut block_ctx)?;
+ }
+ spirv::Op::FunctionEnd => {
+ fun_inst.expect(1)?;
+ break;
+ }
+ _ => {
+ return Err(Error::UnsupportedInstruction(self.state, fun_inst.op));
+ }
+ }
+ }
+
+ if let Some(ref prefix) = self.options.block_ctx_dump_prefix {
+ let dump_suffix = match self.lookup_entry_point.get(&fun_id) {
+ Some(ep) => format!("block_ctx.{:?}-{}.txt", ep.stage, ep.name),
+ None => format!("block_ctx.Fun-{}.txt", module.functions.len()),
+ };
+ let dest = prefix.join(dump_suffix);
+ let dump = format!("{block_ctx:#?}");
+ if let Err(e) = std::fs::write(&dest, dump) {
+ log::error!("Unable to dump the block context into {:?}: {}", dest, e);
+ }
+ }
+
+ // Emit `Store` statements to properly initialize all the local variables we
+ // created for `phi` expressions.
+ //
+ // Note that get_expr_handle also contributes slightly odd entries to this table,
+ // to get the spill.
+ for phi in block_ctx.phis.iter() {
+ // Get a pointer to the local variable for the phi's value.
+ let phi_pointer = block_ctx.expressions.append(
+ crate::Expression::LocalVariable(phi.local),
+ crate::Span::default(),
+ );
+
+ // At the end of each of `phi`'s predecessor blocks, store the corresponding
+ // source value in the phi's local variable.
+ for &(source, predecessor) in phi.expressions.iter() {
+ let source_lexp = &self.lookup_expression[&source];
+ let predecessor_body_idx = block_ctx.body_for_label[&predecessor];
+ // If the expression is a global/argument it will have a 0 block
+ // id so we must use a default value instead of panicking
+ let source_body_idx = block_ctx
+ .body_for_label
+ .get(&source_lexp.block_id)
+ .copied()
+ .unwrap_or(0);
+
+ // If the Naga `Expression` generated for `source` is in scope, then we
+ // can simply store that in the phi's local variable.
+ //
+ // Otherwise, spill the source value to a local variable in the block that
+ // defines it. (We know this store dominates the predecessor; otherwise,
+ // the phi wouldn't have been able to refer to that source expression in
+ // the first place.) Then, the predecessor block can count on finding the
+ // source's value in that local variable.
+ let value = if super::is_parent(predecessor_body_idx, source_body_idx, &block_ctx) {
+ source_lexp.handle
+ } else {
+ // The source SPIR-V expression is not defined in the phi's
+ // predecessor block, nor is it a globally available expression. So it
+ // must be defined off in some other block that merely dominates the
+ // predecessor. This means that the corresponding Naga `Expression`
+ // may not be in scope in the predecessor block.
+ //
+ // In the block that defines `source`, spill it to a fresh local
+ // variable, to ensure we can still use it at the end of the
+ // predecessor.
+ let ty = self.lookup_type[&source_lexp.type_id].handle;
+ let local = block_ctx.local_arena.append(
+ crate::LocalVariable {
+ name: None,
+ ty,
+ init: None,
+ },
+ crate::Span::default(),
+ );
+
+ let pointer = block_ctx.expressions.append(
+ crate::Expression::LocalVariable(local),
+ crate::Span::default(),
+ );
+
+ // Get the spilled value of the source expression.
+ let start = block_ctx.expressions.len();
+ let expr = block_ctx
+ .expressions
+ .append(crate::Expression::Load { pointer }, crate::Span::default());
+ let range = block_ctx.expressions.range_from(start);
+
+ block_ctx
+ .blocks
+ .get_mut(&predecessor)
+ .unwrap()
+ .push(crate::Statement::Emit(range), crate::Span::default());
+
+ // At the end of the block that defines it, spill the source
+ // expression's value.
+ block_ctx
+ .blocks
+ .get_mut(&source_lexp.block_id)
+ .unwrap()
+ .push(
+ crate::Statement::Store {
+ pointer,
+ value: source_lexp.handle,
+ },
+ crate::Span::default(),
+ );
+
+ expr
+ };
+
+ // At the end of the phi predecessor block, store the source
+ // value in the phi's value.
+ block_ctx.blocks.get_mut(&predecessor).unwrap().push(
+ crate::Statement::Store {
+ pointer: phi_pointer,
+ value,
+ },
+ crate::Span::default(),
+ )
+ }
+ }
+
+ fun.body = block_ctx.lower();
+
+ // done
+ let fun_handle = module.functions.append(fun, self.span_from_with_op(start));
+ self.lookup_function.insert(
+ fun_id,
+ super::LookupFunction {
+ handle: fun_handle,
+ parameters_sampling,
+ },
+ );
+
+ if let Some(ep) = self.lookup_entry_point.remove(&fun_id) {
+ // create a wrapping function
+ let mut function = crate::Function {
+ name: Some(format!("{}_wrap", ep.name)),
+ arguments: Vec::new(),
+ result: None,
+ local_variables: Arena::new(),
+ expressions: Arena::new(),
+ named_expressions: crate::NamedExpressions::default(),
+ body: crate::Block::new(),
+ };
+
+ // 1. copy the inputs from arguments to privates
+ for &v_id in ep.variable_ids.iter() {
+ let lvar = self.lookup_variable.lookup(v_id)?;
+ if let super::Variable::Input(ref arg) = lvar.inner {
+ let span = module.global_variables.get_span(lvar.handle);
+ let arg_expr = function.expressions.append(
+ crate::Expression::FunctionArgument(function.arguments.len() as u32),
+ span,
+ );
+ let load_expr = if arg.ty == module.global_variables[lvar.handle].ty {
+ arg_expr
+ } else {
+ // The only case where the type is different is if we need to treat
+ // unsigned integer as signed.
+ let mut emitter = Emitter::default();
+ emitter.start(&function.expressions);
+ let handle = function.expressions.append(
+ crate::Expression::As {
+ expr: arg_expr,
+ kind: crate::ScalarKind::Sint,
+ convert: Some(4),
+ },
+ span,
+ );
+ function.body.extend(emitter.finish(&function.expressions));
+ handle
+ };
+ function.body.push(
+ crate::Statement::Store {
+ pointer: function
+ .expressions
+ .append(crate::Expression::GlobalVariable(lvar.handle), span),
+ value: load_expr,
+ },
+ span,
+ );
+
+ let mut arg = arg.clone();
+ if ep.stage == crate::ShaderStage::Fragment {
+ if let Some(ref mut binding) = arg.binding {
+ binding.apply_default_interpolation(&module.types[arg.ty].inner);
+ }
+ }
+ function.arguments.push(arg);
+ }
+ }
+ // 2. call the wrapped function
+ let fake_id = !(module.entry_points.len() as u32); // doesn't matter, as long as it's not a collision
+ let dummy_handle = self.add_call(fake_id, fun_id);
+ function.body.push(
+ crate::Statement::Call {
+ function: dummy_handle,
+ arguments: Vec::new(),
+ result: None,
+ },
+ crate::Span::default(),
+ );
+
+ // 3. copy the outputs from privates to the result
+ let mut members = Vec::new();
+ let mut components = Vec::new();
+ for &v_id in ep.variable_ids.iter() {
+ let lvar = self.lookup_variable.lookup(v_id)?;
+ if let super::Variable::Output(ref result) = lvar.inner {
+ let span = module.global_variables.get_span(lvar.handle);
+ let expr_handle = function
+ .expressions
+ .append(crate::Expression::GlobalVariable(lvar.handle), span);
+
+ // Cull problematic builtins of gl_PerVertex.
+ // See the docs for `Frontend::gl_per_vertex_builtin_access`.
+ {
+ let ty = &module.types[result.ty];
+ match ty.inner {
+ crate::TypeInner::Struct {
+ members: ref original_members,
+ span,
+ } if ty.name.as_deref() == Some("gl_PerVertex") => {
+ let mut new_members = original_members.clone();
+ for member in &mut new_members {
+ if let Some(crate::Binding::BuiltIn(built_in)) = member.binding
+ {
+ if !self.gl_per_vertex_builtin_access.contains(&built_in) {
+ member.binding = None
+ }
+ }
+ }
+ if &new_members != original_members {
+ module.types.replace(
+ result.ty,
+ crate::Type {
+ name: ty.name.clone(),
+ inner: crate::TypeInner::Struct {
+ members: new_members,
+ span,
+ },
+ },
+ );
+ }
+ }
+ _ => {}
+ }
+ }
+
+ match module.types[result.ty].inner {
+ crate::TypeInner::Struct {
+ members: ref sub_members,
+ ..
+ } => {
+ for (index, sm) in sub_members.iter().enumerate() {
+ if sm.binding.is_none() {
+ continue;
+ }
+ let mut sm = sm.clone();
+
+ if let Some(ref mut binding) = sm.binding {
+ if ep.stage == crate::ShaderStage::Vertex {
+ binding.apply_default_interpolation(
+ &module.types[sm.ty].inner,
+ );
+ }
+ }
+
+ members.push(sm);
+
+ components.push(function.expressions.append(
+ crate::Expression::AccessIndex {
+ base: expr_handle,
+ index: index as u32,
+ },
+ span,
+ ));
+ }
+ }
+ ref inner => {
+ let mut binding = result.binding.clone();
+ if let Some(ref mut binding) = binding {
+ if ep.stage == crate::ShaderStage::Vertex {
+ binding.apply_default_interpolation(inner);
+ }
+ }
+
+ members.push(crate::StructMember {
+ name: None,
+ ty: result.ty,
+ binding,
+ offset: 0,
+ });
+ // populate just the globals first, then do `Load` in a
+ // separate step, so that we can get a range.
+ components.push(expr_handle);
+ }
+ }
+ }
+ }
+
+ for (member_index, member) in members.iter().enumerate() {
+ match member.binding {
+ Some(crate::Binding::BuiltIn(crate::BuiltIn::Position { .. }))
+ if self.options.adjust_coordinate_space =>
+ {
+ let mut emitter = Emitter::default();
+ emitter.start(&function.expressions);
+ let global_expr = components[member_index];
+ let span = function.expressions.get_span(global_expr);
+ let access_expr = function.expressions.append(
+ crate::Expression::AccessIndex {
+ base: global_expr,
+ index: 1,
+ },
+ span,
+ );
+ let load_expr = function.expressions.append(
+ crate::Expression::Load {
+ pointer: access_expr,
+ },
+ span,
+ );
+ let neg_expr = function.expressions.append(
+ crate::Expression::Unary {
+ op: crate::UnaryOperator::Negate,
+ expr: load_expr,
+ },
+ span,
+ );
+ function.body.extend(emitter.finish(&function.expressions));
+ function.body.push(
+ crate::Statement::Store {
+ pointer: access_expr,
+ value: neg_expr,
+ },
+ span,
+ );
+ }
+ _ => {}
+ }
+ }
+
+ let mut emitter = Emitter::default();
+ emitter.start(&function.expressions);
+ for component in components.iter_mut() {
+ let load_expr = crate::Expression::Load {
+ pointer: *component,
+ };
+ let span = function.expressions.get_span(*component);
+ *component = function.expressions.append(load_expr, span);
+ }
+
+ match members[..] {
+ [] => {}
+ [ref member] => {
+ function.body.extend(emitter.finish(&function.expressions));
+ let span = function.expressions.get_span(components[0]);
+ function.body.push(
+ crate::Statement::Return {
+ value: components.first().cloned(),
+ },
+ span,
+ );
+ function.result = Some(crate::FunctionResult {
+ ty: member.ty,
+ binding: member.binding.clone(),
+ });
+ }
+ _ => {
+ let span = crate::Span::total_span(
+ components.iter().map(|h| function.expressions.get_span(*h)),
+ );
+ let ty = module.types.insert(
+ crate::Type {
+ name: None,
+ inner: crate::TypeInner::Struct {
+ members,
+ span: 0xFFFF, // shouldn't matter
+ },
+ },
+ span,
+ );
+ let result_expr = function
+ .expressions
+ .append(crate::Expression::Compose { ty, components }, span);
+ function.body.extend(emitter.finish(&function.expressions));
+ function.body.push(
+ crate::Statement::Return {
+ value: Some(result_expr),
+ },
+ span,
+ );
+ function.result = Some(crate::FunctionResult { ty, binding: None });
+ }
+ }
+
+ module.entry_points.push(crate::EntryPoint {
+ name: ep.name,
+ stage: ep.stage,
+ early_depth_test: ep.early_depth_test,
+ workgroup_size: ep.workgroup_size,
+ function,
+ });
+ }
+
+ Ok(())
+ }
+}
+
+impl<'function> BlockContext<'function> {
+ pub(super) fn gctx(&self) -> crate::proc::GlobalCtx {
+ crate::proc::GlobalCtx {
+ types: self.type_arena,
+ constants: self.const_arena,
+ const_expressions: self.const_expressions,
+ }
+ }
+
+ /// Consumes the `BlockContext` producing a Ir [`Block`](crate::Block)
+ fn lower(mut self) -> crate::Block {
+ fn lower_impl(
+ blocks: &mut crate::FastHashMap<spirv::Word, crate::Block>,
+ bodies: &[super::Body],
+ body_idx: BodyIndex,
+ ) -> crate::Block {
+ let mut block = crate::Block::new();
+
+ for item in bodies[body_idx].data.iter() {
+ match *item {
+ super::BodyFragment::BlockId(id) => block.append(blocks.get_mut(&id).unwrap()),
+ super::BodyFragment::If {
+ condition,
+ accept,
+ reject,
+ } => {
+ let accept = lower_impl(blocks, bodies, accept);
+ let reject = lower_impl(blocks, bodies, reject);
+
+ block.push(
+ crate::Statement::If {
+ condition,
+ accept,
+ reject,
+ },
+ crate::Span::default(),
+ )
+ }
+ super::BodyFragment::Loop {
+ body,
+ continuing,
+ break_if,
+ } => {
+ let body = lower_impl(blocks, bodies, body);
+ let continuing = lower_impl(blocks, bodies, continuing);
+
+ block.push(
+ crate::Statement::Loop {
+ body,
+ continuing,
+ break_if,
+ },
+ crate::Span::default(),
+ )
+ }
+ super::BodyFragment::Switch {
+ selector,
+ ref cases,
+ default,
+ } => {
+ let mut ir_cases: Vec<_> = cases
+ .iter()
+ .map(|&(value, body_idx)| {
+ let body = lower_impl(blocks, bodies, body_idx);
+
+ // Handle simple cases that would make a fallthrough statement unreachable code
+ let fall_through = body.last().map_or(true, |s| !s.is_terminator());
+
+ crate::SwitchCase {
+ value: crate::SwitchValue::I32(value),
+ body,
+ fall_through,
+ }
+ })
+ .collect();
+ ir_cases.push(crate::SwitchCase {
+ value: crate::SwitchValue::Default,
+ body: lower_impl(blocks, bodies, default),
+ fall_through: false,
+ });
+
+ block.push(
+ crate::Statement::Switch {
+ selector,
+ cases: ir_cases,
+ },
+ crate::Span::default(),
+ )
+ }
+ super::BodyFragment::Break => {
+ block.push(crate::Statement::Break, crate::Span::default())
+ }
+ super::BodyFragment::Continue => {
+ block.push(crate::Statement::Continue, crate::Span::default())
+ }
+ }
+ }
+
+ block
+ }
+
+ lower_impl(&mut self.blocks, &self.bodies, 0)
+ }
+}