[WIP] qptr/simplify: add "partition" and "propagate" passes for funct…

…ion-local variables.

examples/spv-lower-link-qptr-lift.rs

@@ -92,6 +92,12 @@ fn main() -> std::io::Result<()> {
  eprintln!("qptr::lower_from_spv_ptrs");
  after_pass("qptr::lower_from_spv_ptrs", &module)?;
 
+ eprint_duration(|| {
+ spirt::passes::qptr::partition_and_propagate(&mut module, layout_config)
+ });
+ eprintln!("qptr::partition_and_propagate");
+ after_pass("qptr::partition_and_propagate", &module)?;
+
  eprint_duration(|| spirt::passes::qptr::analyze_uses(&mut module, layout_config));
  eprintln!("qptr::analyze_uses");
  after_pass("qptr::analyze_uses", &module)?;

src/passes/qptr.rs

@@ -1,7 +1,7 @@
 //! [`QPtr`](crate::TypeKind::QPtr) transforms.
 
 use crate::visit::{InnerVisit, Visitor};
-use crate::{qptr, DataInstForm};
+use crate::{qptr, DataInstForm, DeclDef};
 use crate::{AttrSet, Const, Context, Func, FxIndexSet, GlobalVar, Module, Type};
 
 pub fn lower_from_spv_ptrs(module: &mut Module, layout_config: &qptr::LayoutConfig) {
@@ -35,6 +35,53 @@ pub fn lower_from_spv_ptrs(module: &mut Module, layout_config: &qptr::LayoutConf
  }
 }
 
+// FIXME(eddyb) split this into separate passes, but the looping complicates things.
+pub fn partition_and_propagate(module: &mut Module, layout_config: &qptr::LayoutConfig) {
+ let cx = &module.cx();
+
+ let (_seen_global_vars, seen_funcs) = {
+ // FIXME(eddyb) reuse this collection work in some kind of "pass manager".
+ let mut collector = ReachableUseCollector {
+ cx,
+ module,
+
+ seen_types: FxIndexSet::default(),
+ seen_consts: FxIndexSet::default(),
+ seen_data_inst_forms: FxIndexSet::default(),
+ seen_global_vars: FxIndexSet::default(),
+ seen_funcs: FxIndexSet::default(),
+ };
+ for (export_key, &exportee) in &module.exports {
+ export_key.inner_visit_with(&mut collector);
+ exportee.inner_visit_with(&mut collector);
+ }
+ (collector.seen_global_vars, collector.seen_funcs)
+ };
+
+ for func in seen_funcs {
+ if let DeclDef::Present(func_def_body) = &mut module.funcs[func].def {
+ // FIXME(eddyb) reuse `LayoutCache` and whatnot, between functions,
+ // or at least iterations of this loop.
+ loop {
+ qptr::simplify::partition_local_vars_in_func(
+ cx.clone(),
+ layout_config,
+ func_def_body,
+ );
+
+ let report = qptr::simplify::propagate_contents_of_local_vars_in_func(
+ cx.clone(),
+ layout_config,
+ func_def_body,
+ );
+ if !report.any_qptrs_propagated {
+ break;
+ }
+ }
+ }
+ }
+}
+
 pub fn analyze_uses(module: &mut Module, layout_config: &qptr::LayoutConfig) {
  qptr::analyze::InferUsage::new(module.cx(), layout_config).infer_usage_in_module(module);
 }

src/qptr/analyze.rs

@@ -1,9 +1,9 @@
 //! [`QPtr`](crate::TypeKind::QPtr) usage analysis (for legalizing/lifting).
 
 // HACK(eddyb) sharing layout code with other modules.
-use super::{layout::*, QPtrMemUsageKind};
+use super::layout::*;
 
-use super::{shapes, QPtrAttr, QPtrMemUsage, QPtrOp, QPtrUsage};
+use super::{shapes, QPtrAttr, QPtrMemUsage, QPtrMemUsageKind, QPtrOp, QPtrUsage};
 use crate::func_at::FuncAt;
 use crate::visit::{InnerVisit, Visitor};
 use crate::{

src/qptr/mod.rs

@@ -18,6 +18,7 @@ mod layout;
 pub mod lift;
 pub mod lower;
 pub mod shapes;
+pub mod simplify;
 
 pub use layout::LayoutConfig;