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Only emit DefAlloc edits when the "checker" feature is enabled.

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This reduces instruction counts by ~2% when disabled.
This commit is contained in:
Amanieu d'Antras
2022-01-11 11:32:16 +00:00
parent d95a9d9399
commit 693fb6a975
5 changed files with 121 additions and 113 deletions
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4
Cargo.toml
View File

@@ -25,4 +25,6 @@ overflow-checks = true
[features]
default = []
fuzzing = ["arbitrary"]
checker = []
fuzzing = ["arbitrary", "checker"]

8
src/checker.rs
View File

@@ -599,17 +599,11 @@ impl<'a, F: Function> Checker<'a, F> {
fn handle_edit(&mut self, block: Block, edit: &Edit) {
log::trace!("checker: adding edit {:?}", edit);
match edit {
&Edit::Move { from, to, to_vreg } => {
&Edit::Move { from, to } => {
self.bb_insts
.get_mut(&block)
.unwrap()
.push(CheckerInst::Move { into: to, from });
if let Some(vreg) = to_vreg {
self.bb_insts
.get_mut(&block)
.unwrap()
.push(CheckerInst::DefAlloc { alloc: to, vreg });
}
}
&Edit::DefAlloc { alloc, vreg } => {
self.bb_insts

120
src/ion/moves.rs
View File

@@ -472,12 +472,15 @@ impl<'a, F: Function> Env<'a, F> {
block = block.next();
}
#[cfg(feature = "checker")]
{
// If this is a blockparam vreg and the start of block
// is in this range, add to blockparam_allocs.
let (blockparam_block, blockparam_idx) =
self.cfginfo.vreg_def_blockparam[vreg.index()];
if blockparam_block.is_valid()
&& range.contains_point(self.cfginfo.block_entry[blockparam_block.index()])
&& range
.contains_point(self.cfginfo.block_entry[blockparam_block.index()])
{
self.blockparam_allocs.push((
blockparam_block,
@@ -487,6 +490,7 @@ impl<'a, F: Function> Env<'a, F> {
));
}
}
}
// Scan over def/uses and apply allocations.
for use_idx in 0..self.ranges[entry.index.index()].uses.len() {
@@ -930,6 +934,7 @@ impl<'a, F: Function> Env<'a, F> {
// regs, but this seems simpler.)
let mut int_moves: SmallVec<[InsertedMove; 8]> = smallvec![];
let mut float_moves: SmallVec<[InsertedMove; 8]> = smallvec![];
#[cfg(feature = "checker")]
let mut self_moves: SmallVec<[InsertedMove; 8]> = smallvec![];
for m in moves {
@@ -937,6 +942,7 @@ impl<'a, F: Function> Env<'a, F> {
debug_assert_eq!(m.from_alloc.class(), m.to_alloc.class());
}
if m.from_alloc == m.to_alloc {
#[cfg(feature = "checker")]
if m.to_vreg.is_some() {
self_moves.push(m.clone());
}
@@ -1002,88 +1008,71 @@ impl<'a, F: Function> Env<'a, F> {
}
if self.allocation_is_stack(src) && self.allocation_is_stack(dst) {
if !scratch_used_yet {
self.add_edit(
self.add_move_edit(
pos,
prio,
Edit::Move {
from: src,
to: Allocation::reg(scratch),
src,
Allocation::reg(scratch),
to_vreg,
},
);
self.add_edit(
self.add_move_edit(
pos,
prio,
Edit::Move {
from: Allocation::reg(scratch),
to: dst,
Allocation::reg(scratch),
dst,
to_vreg,
},
);
} else {
debug_assert!(extra_slot.is_some());
self.add_edit(
self.add_move_edit(
pos,
prio,
Edit::Move {
from: Allocation::reg(scratch),
to: extra_slot.unwrap(),
to_vreg: None,
},
Allocation::reg(scratch),
extra_slot.unwrap(),
None,
);
self.add_edit(
self.add_move_edit(
pos,
prio,
Edit::Move {
from: src,
to: Allocation::reg(scratch),
src,
Allocation::reg(scratch),
to_vreg,
},
);
self.add_edit(
self.add_move_edit(
pos,
prio,
Edit::Move {
from: Allocation::reg(scratch),
to: dst,
Allocation::reg(scratch),
dst,
to_vreg,
},
);
self.add_edit(
self.add_move_edit(
pos,
prio,
Edit::Move {
from: extra_slot.unwrap(),
to: Allocation::reg(scratch),
to_vreg: None,
},
extra_slot.unwrap(),
Allocation::reg(scratch),
None,
);
}
} else {
self.add_edit(
pos,
prio,
Edit::Move {
from: src,
to: dst,
to_vreg,
},
);
self.add_move_edit(pos, prio, src, dst, to_vreg);
}
} else {
log::trace!(" -> redundant move elided");
}
#[cfg(feature = "checker")]
if let Some((alloc, vreg)) = action.def_alloc {
log::trace!(
" -> converted to DefAlloc: alloc {} vreg {}",
alloc,
vreg
);
self.add_edit(pos, prio, Edit::DefAlloc { alloc, vreg });
self.edits
.push((pos.to_index(), prio, Edit::DefAlloc { alloc, vreg }));
}
}
}
#[cfg(feature = "checker")]
for m in &self_moves {
log::trace!(
"self move at pos {:?} prio {:?}: {} -> {} to_vreg {:?}",
@@ -1097,11 +1086,14 @@ impl<'a, F: Function> Env<'a, F> {
debug_assert!(action.elide);
if let Some((alloc, vreg)) = action.def_alloc {
log::trace!(" -> DefAlloc: alloc {} vreg {}", alloc, vreg);
self.add_edit(pos, prio, Edit::DefAlloc { alloc, vreg });
self.edits
.push((pos.to_index(), prio, Edit::DefAlloc { alloc, vreg }));
}
}
}
#[cfg(feature = "checker")]
{
// Add edits to describe blockparam locations too. This is
// required by the checker. This comes after any edge-moves.
self.blockparam_allocs
@@ -1126,11 +1118,12 @@ impl<'a, F: Function> Env<'a, F> {
debug_assert_eq!(vregs.len(), self.func.block_params(block).len());
debug_assert_eq!(allocs.len(), self.func.block_params(block).len());
for (vreg, alloc) in vregs.into_iter().zip(allocs.into_iter()) {
self.add_edit(
self.cfginfo.block_entry[block.index()],
self.edits.push((
self.cfginfo.block_entry[block.index()].to_index(),
InsertMovePrio::BlockParam,
Edit::DefAlloc { alloc, vreg },
);
));
}
}
}
@@ -1147,10 +1140,10 @@ impl<'a, F: Function> Env<'a, F> {
for i in 0..self.edits.len() {
let &(pos, _, ref edit) = &self.edits[i];
match edit {
&Edit::Move { from, to, to_vreg } => {
&Edit::Move { from, to } => {
self.annotate(
ProgPoint::from_index(pos),
format!("move {} -> {} ({:?})", from, to, to_vreg),
format!("move {} -> {})", from, to),
);
}
&Edit::DefAlloc { alloc, vreg } => {
@@ -1162,15 +1155,32 @@ impl<'a, F: Function> Env<'a, F> {
}
}
pub fn add_edit(&mut self, pos: ProgPoint, prio: InsertMovePrio, edit: Edit) {
match &edit {
&Edit::Move { from, to, to_vreg } if from == to && to_vreg.is_none() => return,
&Edit::Move { from, to, .. } if from.is_reg() && to.is_reg() => {
pub fn add_move_edit(
&mut self,
pos: ProgPoint,
prio: InsertMovePrio,
from: Allocation,
to: Allocation,
_to_vreg: Option<VReg>,
) {
if from != to {
if from.is_reg() && to.is_reg() {
debug_assert_eq!(from.as_reg().unwrap().class(), to.as_reg().unwrap().class());
}
_ => {}
self.edits
.push((pos.to_index(), prio, Edit::Move { from, to }));
}
self.edits.push((pos.to_index(), prio, edit));
#[cfg(feature = "checker")]
if let Some(to_vreg) = _to_vreg {
self.edits.push((
pos.to_index(),
prio,
Edit::DefAlloc {
alloc: to,
vreg: to_vreg,
},
));
}
}
}

8
src/ion/redundant_moves.rs
View File

@@ -18,6 +18,7 @@ pub struct RedundantMoveEliminator {
#[derive(Copy, Clone, Debug)]
pub struct RedundantMoveAction {
pub elide: bool,
#[cfg(feature = "checker")]
pub def_alloc: Option<(Allocation, VReg)>,
}
@@ -58,6 +59,7 @@ impl RedundantMoveEliminator {
.insert(to, RedundantMoveState::Orig(to_vreg.unwrap()));
return RedundantMoveAction {
elide: true,
#[cfg(feature = "checker")]
def_alloc: Some((to, to_vreg.unwrap())),
};
}
@@ -111,7 +113,11 @@ impl RedundantMoveEliminator {
.push(to);
}
RedundantMoveAction { elide, def_alloc }
RedundantMoveAction {
elide,
#[cfg(feature = "checker")]
def_alloc,
}
}
pub fn clear(&mut self) {

12
src/lib.rs
View File

@@ -1105,20 +1105,16 @@ pub enum Edit {
/// register or a stack slot (spillslot). However, stack-to-stack
/// moves will never be generated.
///
/// `to_vreg`, if defined, is useful as metadata: it indicates
/// that the moved value is a def of a new vreg.
///
/// `Move` edits will be generated even if src and dst allocation
/// are the same if the vreg changes; this allows proper metadata
/// tracking even when moves are elided.
Move {
from: Allocation,
to: Allocation,
to_vreg: Option<VReg>,
},
Move { from: Allocation, to: Allocation },
/// Define a particular Allocation to contain a particular VReg. Useful
/// for the checker.
///
/// `DefAlloc` edits are only emitted when the `"checker"` Cargo feature is
/// enabled.
DefAlloc { alloc: Allocation, vreg: VReg },
}