mikros/rust
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Auto merge of #107851 - cjgillot:sroa-const, r=oli-obk

Browse Source 
Put deaggregated statements after original constant.

Fixes https://github.com/rust-lang/rust/issues/107818
This commit is contained in:
bors 2023-02-11 20:59:18 +00:00
commit 585f3eef26
3 changed files with 57 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
compiler/rustc_mir_transform/src/sroa.rs
View File

@ -318,6 +318,8 @@ fn visit_statement(&mut self, statement: &mut Statement<'tcx>, location: Locatio
// ConstProp will pick up the pieces and replace them by actual constants.
StatementKind::Assign(box (place, Rvalue::Use(Operand::Constant(_)))) => {
if let Some(final_locals) = self.replacements.place_fragments(place) {
// Put the deaggregated statements *after* the original one.
let location = location.successor_within_block();
for (field, ty, new_local) in final_locals {
let rplace = self.tcx.mk_place_field(place, field, ty);
let rvalue = Rvalue::Use(Operand::Move(rplace));

46
tests/mir-opt/sroa.constant.ScalarReplacementOfAggregates.diff Normal file
View File

@ -0,0 +1,46 @@
- // MIR for `constant` before ScalarReplacementOfAggregates
+ // MIR for `constant` after ScalarReplacementOfAggregates
fn constant() -> () {
let mut _0: (); // return place in scope 0 at $DIR/sroa.rs:+0:15: +0:15
let _1: (usize, u8); // in scope 0 at $DIR/sroa.rs:+2:9: +2:10
+ let _4: usize; // in scope 0 at $DIR/sroa.rs:+2:9: +2:10
+ let _5: u8; // in scope 0 at $DIR/sroa.rs:+2:9: +2:10
scope 1 {
- debug y => _1; // in scope 1 at $DIR/sroa.rs:+2:9: +2:10
+ debug y => (usize, u8){ .0 => _4, .1 => _5, }; // in scope 1 at $DIR/sroa.rs:+2:9: +2:10
let _2: usize; // in scope 1 at $DIR/sroa.rs:+3:9: +3:10
scope 2 {
debug t => _2; // in scope 2 at $DIR/sroa.rs:+3:9: +3:10
let _3: u8; // in scope 2 at $DIR/sroa.rs:+4:9: +4:10
scope 3 {
debug u => _3; // in scope 3 at $DIR/sroa.rs:+4:9: +4:10
}
}
}
bb0: {
- StorageLive(_1); // scope 0 at $DIR/sroa.rs:+2:9: +2:10
+ StorageLive(_4); // scope 0 at $DIR/sroa.rs:+2:9: +2:10
+ StorageLive(_5); // scope 0 at $DIR/sroa.rs:+2:9: +2:10
+ nop; // scope 0 at $DIR/sroa.rs:+2:9: +2:10
_1 = const _; // scope 0 at $DIR/sroa.rs:+2:13: +2:14
+ _4 = move (_1.0: usize); // scope 1 at $DIR/sroa.rs:+3:9: +3:10
+ _5 = move (_1.1: u8); // scope 1 at $DIR/sroa.rs:+3:9: +3:10
StorageLive(_2); // scope 1 at $DIR/sroa.rs:+3:9: +3:10
- _2 = (_1.0: usize); // scope 1 at $DIR/sroa.rs:+3:13: +3:16
+ _2 = _4; // scope 1 at $DIR/sroa.rs:+3:13: +3:16
StorageLive(_3); // scope 2 at $DIR/sroa.rs:+4:9: +4:10
- _3 = (_1.1: u8); // scope 2 at $DIR/sroa.rs:+4:13: +4:16
+ _3 = _5; // scope 2 at $DIR/sroa.rs:+4:13: +4:16
_0 = const (); // scope 0 at $DIR/sroa.rs:+0:15: +5:2
StorageDead(_3); // scope 2 at $DIR/sroa.rs:+5:1: +5:2
StorageDead(_2); // scope 1 at $DIR/sroa.rs:+5:1: +5:2
- StorageDead(_1); // scope 0 at $DIR/sroa.rs:+5:1: +5:2
+ StorageDead(_4); // scope 0 at $DIR/sroa.rs:+5:1: +5:2
+ StorageDead(_5); // scope 0 at $DIR/sroa.rs:+5:1: +5:2
+ nop; // scope 0 at $DIR/sroa.rs:+5:1: +5:2
return; // scope 0 at $DIR/sroa.rs:+5:2: +5:2
}
}

9
tests/mir-opt/sroa.rs
View File

@ -87,6 +87,13 @@ fn ref_copies(x: &Foo) {
let u = y.c;
}
fn constant() {
const U: (usize, u8) = (5, 9);
let y = U;
let t = y.0;
let u = y.1;
}
fn main() {
dropping();
enums(5);
@ -96,6 +103,7 @@ fn main() {
escaping();
copies(Foo { a: 5, b: (), c: "a", d: Some(-4) });
ref_copies(&Foo { a: 5, b: (), c: "a", d: Some(-4) });
constant();
}
// EMIT_MIR sroa.dropping.ScalarReplacementOfAggregates.diff
@ -106,3 +114,4 @@ fn main() {
// EMIT_MIR sroa.escaping.ScalarReplacementOfAggregates.diff
// EMIT_MIR sroa.copies.ScalarReplacementOfAggregates.diff
// EMIT_MIR sroa.ref_copies.ScalarReplacementOfAggregates.diff
// EMIT_MIR sroa.constant.ScalarReplacementOfAggregates.diff