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Include emergency stack slots when laying out the stack.

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Emergency stack slots are a new kind of stack slot added relatively
recently. They need to be allocated a stack offset just like explicit
and spill slots.

Also, make StackSlotData's offset field an Option, to catch problems
like this in the future. Previously the value 0 was used when offsets
weren't assigned yet, however that made it non-obvious when the field
meant "not assigned yet" and when it meant "assigned the value 0".
This commit is contained in:
Dan Gohman
2018-03-03 13:21:10 -08:00
parent a301280d94
commit 13b167770c
9 changed files with 81 additions and 60 deletions
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22
lib/cretonne/src/ir/stackslot.rs
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@@ -111,7 +111,7 @@ pub struct StackSlotData {
///
/// For `OutgoingArg` stack slots, the offset is relative to the current function's stack
/// pointer immediately before the call.
pub offset: StackOffset,
pub offset: Option<StackOffset>,
}
impl StackSlotData {
@@ -120,7 +120,7 @@ impl StackSlotData {
StackSlotData {
kind,
size,
offset: 0,
offset: None,
}
}
@@ -138,8 +138,8 @@ impl StackSlotData {
impl fmt::Display for StackSlotData {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "{} {}", self.kind, self.size)?;
if self.offset != 0 {
write!(f, ", offset {}", self.offset)?;
if let Some(offset) = self.offset {
write!(f, ", offset {}", offset)?;
}
Ok(())
}
@@ -204,7 +204,7 @@ impl StackSlots {
/// Set the offset of a stack slot.
pub fn set_offset(&mut self, ss: StackSlot, offset: StackOffset) {
self.slots[ss].offset = offset;
self.slots[ss].offset = Some(offset);
}
/// Get an iterator over all the stack slot keys.
@@ -245,7 +245,7 @@ impl StackSlots {
pub fn make_incoming_arg(&mut self, ty: Type, offset: StackOffset) -> StackSlot {
let mut data = StackSlotData::new(StackSlotKind::IncomingArg, ty.bytes());
assert!(offset <= StackOffset::max_value() - data.size as StackOffset);
data.offset = offset;
data.offset = Some(offset);
self.push(data)
}
@@ -261,7 +261,7 @@ impl StackSlots {
// Look for an existing outgoing stack slot with the same offset and size.
let inspos = match self.outgoing.binary_search_by_key(&(offset, size), |&ss| {
(self[ss].offset, self[ss].size)
(self[ss].offset.unwrap(), self[ss].size)
}) {
Ok(idx) => return self.outgoing[idx],
Err(idx) => idx,
@@ -270,7 +270,7 @@ impl StackSlots {
// No existing slot found. Make one and insert it into `outgoing`.
let mut data = StackSlotData::new(StackSlotKind::OutgoingArg, size);
assert!(offset <= StackOffset::max_value() - size as StackOffset);
data.offset = offset;
data.offset = Some(offset);
let ss = self.slots.push(data);
self.outgoing.insert(inspos, ss);
ss
@@ -344,13 +344,13 @@ mod tests {
let ss1 = sss.get_outgoing_arg(types::I32, 4);
let ss2 = sss.get_outgoing_arg(types::I64, 8);
assert_eq!(sss[ss0].offset, 8);
assert_eq!(sss[ss0].offset, Some(8));
assert_eq!(sss[ss0].size, 4);
assert_eq!(sss[ss1].offset, 4);
assert_eq!(sss[ss1].offset, Some(4));
assert_eq!(sss[ss1].size, 4);
assert_eq!(sss[ss2].offset, 8);
assert_eq!(sss[ss2].offset, Some(8));
assert_eq!(sss[ss2].size, 8);
assert_eq!(sss.get_outgoing_arg(types::I32, 8), ss0);