Auto merge of #105119 - JakobDegen:inline-experiments, r=cjgillot

Disable top down MIR inlining

The current MIR inliner has exponential behavior in some cases: <https://godbolt.org/z/7jnWah4fE>. The cause of this is top-down inlining, where we repeatedly do inlining like `call_a() => { call_b(); call_b(); }`. Each decision on its own seems to make sense, but the result is exponential.

Disabling top-down inlining fundamentally prevents this. Each call site in the original, unoptimized source code is now considered for inlining exactly one time, which means that the total growth in MIR size is limited to number of call sites * inlining threshold.

Top down inlining may be worth re-introducing at some point, but it needs to be accompanied with a principled way to prevent this kind of behavior.
This commit is contained in:
bors 2022-12-06 00:53:01 +00:00
commit 226202d902
10 changed files with 245 additions and 117 deletions

View File

@ -8,7 +8,6 @@ use rustc_middle::mir::visit::*;
use rustc_middle::mir::*;
use rustc_middle::ty::{self, Instance, InstanceDef, ParamEnv, Ty, TyCtxt};
use rustc_session::config::OptLevel;
use rustc_span::def_id::DefId;
use rustc_span::{hygiene::ExpnKind, ExpnData, LocalExpnId, Span};
use rustc_target::abi::VariantIdx;
use rustc_target::spec::abi::Abi;
@ -87,13 +86,8 @@ fn inline<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) -> bool {
let param_env = tcx.param_env_reveal_all_normalized(def_id);
let mut this = Inliner {
tcx,
param_env,
codegen_fn_attrs: tcx.codegen_fn_attrs(def_id),
history: Vec::new(),
changed: false,
};
let mut this =
Inliner { tcx, param_env, codegen_fn_attrs: tcx.codegen_fn_attrs(def_id), changed: false };
let blocks = BasicBlock::new(0)..body.basic_blocks.next_index();
this.process_blocks(body, blocks);
this.changed
@ -104,12 +98,6 @@ struct Inliner<'tcx> {
param_env: ParamEnv<'tcx>,
/// Caller codegen attributes.
codegen_fn_attrs: &'tcx CodegenFnAttrs,
/// Stack of inlined instances.
/// We only check the `DefId` and not the substs because we want to
/// avoid inlining cases of polymorphic recursion.
/// The number of `DefId`s is finite, so checking history is enough
/// to ensure that we do not loop endlessly while inlining.
history: Vec<DefId>,
/// Indicates that the caller body has been modified.
changed: bool,
}
@ -134,12 +122,12 @@ impl<'tcx> Inliner<'tcx> {
debug!("not-inlined {} [{}]", callsite.callee, reason);
continue;
}
Ok(new_blocks) => {
Ok(_) => {
debug!("inlined {}", callsite.callee);
self.changed = true;
self.history.push(callsite.callee.def_id());
self.process_blocks(caller_body, new_blocks);
self.history.pop();
// We could process the blocks returned by `try_inlining` here. However, that
// leads to exponential compile times due to the top-down nature of this kind
// of inlining.
}
}
}
@ -313,10 +301,6 @@ impl<'tcx> Inliner<'tcx> {
return None;
}
if self.history.contains(&callee.def_id()) {
return None;
}
let fn_sig = self.tcx.bound_fn_sig(def_id).subst(self.tcx, substs);
return Some(CallSite {

View File

@ -10,8 +10,6 @@
+ let _3: (); // in scope 1 at $DIR/cycle.rs:6:5: 6:8
+ let mut _4: &fn() {main}; // in scope 1 at $DIR/cycle.rs:6:5: 6:6
+ let mut _5: (); // in scope 1 at $DIR/cycle.rs:6:5: 6:8
+ scope 2 (inlined <fn() {main} as Fn<()>>::call - shim(fn() {main})) { // at $DIR/cycle.rs:6:5: 6:8
+ }
+ }
bb0: {
@ -29,7 +27,10 @@
+ StorageLive(_4); // scope 1 at $DIR/cycle.rs:6:5: 6:6
+ _4 = &_2; // scope 1 at $DIR/cycle.rs:6:5: 6:6
+ StorageLive(_5); // scope 1 at $DIR/cycle.rs:6:5: 6:8
+ _3 = move (*_4)() -> [return: bb4, unwind: bb2]; // scope 2 at $SRC_DIR/core/src/ops/function.rs:LL:COL
+ _3 = <fn() {main} as Fn<()>>::call(move _4, move _5) -> [return: bb2, unwind: bb3]; // scope 1 at $DIR/cycle.rs:6:5: 6:8
+ // mir::Constant
+ // + span: $DIR/cycle.rs:6:5: 6:6
+ // + literal: Const { ty: for<'a> extern "rust-call" fn(&'a fn() {main}, ()) -> <fn() {main} as FnOnce<()>>::Output {<fn() {main} as Fn<()>>::call}, val: Value(<ZST>) }
}
bb1: {
@ -39,19 +40,19 @@
return; // scope 0 at $DIR/cycle.rs:+2:2: +2:2
+ }
+
+ bb2 (cleanup): {
+ drop(_2) -> bb3; // scope 1 at $DIR/cycle.rs:7:1: 7:2
+ }
+
+ bb3 (cleanup): {
+ resume; // scope 1 at $DIR/cycle.rs:5:1: 7:2
+ }
+
+ bb4: {
+ bb2: {
+ StorageDead(_5); // scope 1 at $DIR/cycle.rs:6:7: 6:8
+ StorageDead(_4); // scope 1 at $DIR/cycle.rs:6:7: 6:8
+ StorageDead(_3); // scope 1 at $DIR/cycle.rs:6:8: 6:9
+ drop(_2) -> bb1; // scope 1 at $DIR/cycle.rs:7:1: 7:2
+ }
+
+ bb3 (cleanup): {
+ drop(_2) -> bb4; // scope 1 at $DIR/cycle.rs:7:1: 7:2
+ }
+
+ bb4 (cleanup): {
+ resume; // scope 1 at $DIR/cycle.rs:5:1: 7:2
}
}

View File

@ -10,18 +10,6 @@
+ let _3: (); // in scope 1 at $DIR/cycle.rs:6:5: 6:8
+ let mut _4: &fn() {g}; // in scope 1 at $DIR/cycle.rs:6:5: 6:6
+ let mut _5: (); // in scope 1 at $DIR/cycle.rs:6:5: 6:8
+ scope 2 (inlined <fn() {g} as Fn<()>>::call - shim(fn() {g})) { // at $DIR/cycle.rs:6:5: 6:8
+ scope 3 (inlined g) { // at $SRC_DIR/core/src/ops/function.rs:LL:COL
+ let mut _6: fn() {main}; // in scope 3 at $DIR/cycle.rs:12:5: 12:12
+ scope 4 (inlined f::<fn() {main}>) { // at $DIR/cycle.rs:12:5: 12:12
+ debug g => _6; // in scope 4 at $DIR/cycle.rs:5:6: 5:7
+ let _7: (); // in scope 4 at $DIR/cycle.rs:6:5: 6:8
+ let mut _8: &fn() {main}; // in scope 4 at $DIR/cycle.rs:6:5: 6:6
+ scope 5 (inlined <fn() {main} as Fn<()>>::call - shim(fn() {main})) { // at $DIR/cycle.rs:6:5: 6:8
+ }
+ }
+ }
+ }
+ }
bb0: {
@ -39,11 +27,10 @@
+ StorageLive(_4); // scope 1 at $DIR/cycle.rs:6:5: 6:6
+ _4 = &_2; // scope 1 at $DIR/cycle.rs:6:5: 6:6
+ StorageLive(_5); // scope 1 at $DIR/cycle.rs:6:5: 6:8
+ StorageLive(_6); // scope 3 at $DIR/cycle.rs:12:5: 12:12
+ StorageLive(_7); // scope 4 at $DIR/cycle.rs:6:5: 6:8
+ StorageLive(_8); // scope 4 at $DIR/cycle.rs:6:5: 6:6
+ _8 = &_6; // scope 4 at $DIR/cycle.rs:6:5: 6:6
+ _7 = move (*_8)() -> [return: bb4, unwind: bb2]; // scope 5 at $SRC_DIR/core/src/ops/function.rs:LL:COL
+ _3 = <fn() {g} as Fn<()>>::call(move _4, move _5) -> [return: bb2, unwind: bb3]; // scope 1 at $DIR/cycle.rs:6:5: 6:8
+ // mir::Constant
+ // + span: $DIR/cycle.rs:6:5: 6:6
+ // + literal: Const { ty: for<'a> extern "rust-call" fn(&'a fn() {g}, ()) -> <fn() {g} as FnOnce<()>>::Output {<fn() {g} as Fn<()>>::call}, val: Value(<ZST>) }
}
bb1: {
@ -53,22 +40,19 @@
return; // scope 0 at $DIR/cycle.rs:+2:2: +2:2
+ }
+
+ bb2 (cleanup): {
+ drop(_2) -> bb3; // scope 1 at $DIR/cycle.rs:7:1: 7:2
+ }
+
+ bb3 (cleanup): {
+ resume; // scope 1 at $DIR/cycle.rs:5:1: 7:2
+ }
+
+ bb4: {
+ StorageDead(_8); // scope 4 at $DIR/cycle.rs:6:7: 6:8
+ StorageDead(_7); // scope 4 at $DIR/cycle.rs:6:8: 6:9
+ StorageDead(_6); // scope 3 at $DIR/cycle.rs:12:5: 12:12
+ bb2: {
+ StorageDead(_5); // scope 1 at $DIR/cycle.rs:6:7: 6:8
+ StorageDead(_4); // scope 1 at $DIR/cycle.rs:6:7: 6:8
+ StorageDead(_3); // scope 1 at $DIR/cycle.rs:6:8: 6:9
+ drop(_2) -> bb1; // scope 1 at $DIR/cycle.rs:7:1: 7:2
+ }
+
+ bb3 (cleanup): {
+ drop(_2) -> bb4; // scope 1 at $DIR/cycle.rs:7:1: 7:2
+ }
+
+ bb4 (cleanup): {
+ resume; // scope 1 at $DIR/cycle.rs:5:1: 7:2
}
}

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@ -0,0 +1,50 @@
- // MIR for `main` before Inline
+ // MIR for `main` after Inline
fn main() -> () {
let mut _0: (); // return place in scope 0 at $DIR/exponential_runtime.rs:+0:11: +0:11
let _1: (); // in scope 0 at $DIR/exponential_runtime.rs:+1:5: +1:22
+ scope 1 (inlined <() as G>::call) { // at $DIR/exponential_runtime.rs:86:5: 86:22
+ let _2: (); // in scope 1 at $DIR/exponential_runtime.rs:73:9: 73:25
+ let _3: (); // in scope 1 at $DIR/exponential_runtime.rs:74:9: 74:25
+ let _4: (); // in scope 1 at $DIR/exponential_runtime.rs:75:9: 75:25
+ }
bb0: {
StorageLive(_1); // scope 0 at $DIR/exponential_runtime.rs:+1:5: +1:22
- _1 = <() as G>::call() -> bb1; // scope 0 at $DIR/exponential_runtime.rs:+1:5: +1:22
+ StorageLive(_2); // scope 1 at $DIR/exponential_runtime.rs:73:9: 73:25
+ _2 = <() as F>::call() -> bb1; // scope 1 at $DIR/exponential_runtime.rs:73:9: 73:25
// mir::Constant
- // + span: $DIR/exponential_runtime.rs:86:5: 86:20
- // + literal: Const { ty: fn() {<() as G>::call}, val: Value(<ZST>) }
+ // + span: $DIR/exponential_runtime.rs:73:9: 73:23
+ // + literal: Const { ty: fn() {<() as F>::call}, val: Value(<ZST>) }
}
bb1: {
+ StorageDead(_2); // scope 1 at $DIR/exponential_runtime.rs:73:25: 73:26
+ StorageLive(_3); // scope 1 at $DIR/exponential_runtime.rs:74:9: 74:25
+ _3 = <() as F>::call() -> bb2; // scope 1 at $DIR/exponential_runtime.rs:74:9: 74:25
+ // mir::Constant
+ // + span: $DIR/exponential_runtime.rs:74:9: 74:23
+ // + literal: Const { ty: fn() {<() as F>::call}, val: Value(<ZST>) }
+ }
+
+ bb2: {
+ StorageDead(_3); // scope 1 at $DIR/exponential_runtime.rs:74:25: 74:26
+ StorageLive(_4); // scope 1 at $DIR/exponential_runtime.rs:75:9: 75:25
+ _4 = <() as F>::call() -> bb3; // scope 1 at $DIR/exponential_runtime.rs:75:9: 75:25
+ // mir::Constant
+ // + span: $DIR/exponential_runtime.rs:75:9: 75:23
+ // + literal: Const { ty: fn() {<() as F>::call}, val: Value(<ZST>) }
+ }
+
+ bb3: {
+ StorageDead(_4); // scope 1 at $DIR/exponential_runtime.rs:75:25: 75:26
StorageDead(_1); // scope 0 at $DIR/exponential_runtime.rs:+1:22: +1:23
_0 = const (); // scope 0 at $DIR/exponential_runtime.rs:+0:11: +2:2
return; // scope 0 at $DIR/exponential_runtime.rs:+2:2: +2:2
}
}

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@ -0,0 +1,87 @@
// Checks that code with exponential runtime does not have exponential behavior in inlining.
trait A {
fn call();
}
trait B {
fn call();
}
impl<T: A> B for T {
#[inline]
fn call() {
<T as A>::call();
<T as A>::call();
<T as A>::call();
}
}
trait C {
fn call();
}
impl<T: B> C for T {
#[inline]
fn call() {
<T as B>::call();
<T as B>::call();
<T as B>::call();
}
}
trait D {
fn call();
}
impl<T: C> D for T {
#[inline]
fn call() {
<T as C>::call();
<T as C>::call();
<T as C>::call();
}
}
trait E {
fn call();
}
impl<T: D> E for T {
#[inline]
fn call() {
<T as D>::call();
<T as D>::call();
<T as D>::call();
}
}
trait F {
fn call();
}
impl<T: E> F for T {
#[inline]
fn call() {
<T as E>::call();
<T as E>::call();
<T as E>::call();
}
}
trait G {
fn call();
}
impl<T: F> G for T {
#[inline]
fn call() {
<T as F>::call();
<T as F>::call();
<T as F>::call();
}
}
impl A for () {
#[inline(never)]
fn call() {}
}
// EMIT_MIR exponential_runtime.main.Inline.diff
fn main() {
<() as G>::call();
}

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@ -5,20 +5,17 @@
let mut _0: (); // return place in scope 0 at $DIR/inline_cycle.rs:+0:10: +0:10
let _1: (); // in scope 0 at $DIR/inline_cycle.rs:+1:5: +1:24
+ scope 1 (inlined <C as Call>::call) { // at $DIR/inline_cycle.rs:14:5: 14:24
+ scope 2 (inlined <A<C> as Call>::call) { // at $DIR/inline_cycle.rs:43:9: 43:23
+ scope 3 (inlined <B<C> as Call>::call) { // at $DIR/inline_cycle.rs:28:9: 28:31
+ }
+ }
+ }
bb0: {
StorageLive(_1); // scope 0 at $DIR/inline_cycle.rs:+1:5: +1:24
- _1 = <C as Call>::call() -> bb1; // scope 0 at $DIR/inline_cycle.rs:+1:5: +1:24
+ _1 = <C as Call>::call() -> bb1; // scope 3 at $DIR/inline_cycle.rs:36:9: 36:28
+ _1 = <A<C> as Call>::call() -> bb1; // scope 1 at $DIR/inline_cycle.rs:43:9: 43:23
// mir::Constant
- // + span: $DIR/inline_cycle.rs:14:5: 14:22
+ // + span: $DIR/inline_cycle.rs:36:9: 36:26
// + literal: Const { ty: fn() {<C as Call>::call}, val: Value(<ZST>) }
- // + literal: Const { ty: fn() {<C as Call>::call}, val: Value(<ZST>) }
+ // + span: $DIR/inline_cycle.rs:43:9: 43:21
+ // + literal: Const { ty: fn() {<A<C> as Call>::call}, val: Value(<ZST>) }
}
bb1: {

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@ -9,11 +9,6 @@
+ debug f => _2; // in scope 1 at $DIR/inline_cycle.rs:53:22: 53:23
+ let _3: (); // in scope 1 at $DIR/inline_cycle.rs:54:5: 54:8
+ let mut _4: (); // in scope 1 at $DIR/inline_cycle.rs:54:5: 54:8
+ scope 2 (inlined <fn() {f} as FnOnce<()>>::call_once - shim(fn() {f})) { // at $DIR/inline_cycle.rs:54:5: 54:8
+ scope 3 (inlined f) { // at $SRC_DIR/core/src/ops/function.rs:LL:COL
+ let _5: (); // in scope 3 at $DIR/inline_cycle.rs:59:5: 59:12
+ }
+ }
+ }
bb0: {
@ -23,23 +18,19 @@
+ _2 = f; // scope 0 at $DIR/inline_cycle.rs:+1:5: +1:12
// mir::Constant
- // + span: $DIR/inline_cycle.rs:49:5: 49:9
+ // + span: $DIR/inline_cycle.rs:49:10: 49:11
+ // + literal: Const { ty: fn() {f}, val: Value(<ZST>) }
- // + literal: Const { ty: fn(fn() {f}) {call::<fn() {f}>}, val: Value(<ZST>) }
- // mir::Constant
// + span: $DIR/inline_cycle.rs:49:10: 49:11
// + literal: Const { ty: fn() {f}, val: Value(<ZST>) }
+ StorageLive(_3); // scope 1 at $DIR/inline_cycle.rs:54:5: 54:8
+ StorageLive(_4); // scope 1 at $DIR/inline_cycle.rs:54:5: 54:8
+ StorageLive(_5); // scope 3 at $DIR/inline_cycle.rs:59:5: 59:12
+ _5 = call::<fn() {f}>(f) -> bb1; // scope 3 at $DIR/inline_cycle.rs:59:5: 59:12
+ _3 = <fn() {f} as FnOnce<()>>::call_once(move _2, move _4) -> bb1; // scope 1 at $DIR/inline_cycle.rs:54:5: 54:8
+ // mir::Constant
+ // + span: $DIR/inline_cycle.rs:59:5: 59:9
// + literal: Const { ty: fn(fn() {f}) {call::<fn() {f}>}, val: Value(<ZST>) }
// mir::Constant
- // + span: $DIR/inline_cycle.rs:49:10: 49:11
+ // + span: $DIR/inline_cycle.rs:59:10: 59:11
// + literal: Const { ty: fn() {f}, val: Value(<ZST>) }
+ // + span: $DIR/inline_cycle.rs:54:5: 54:6
+ // + literal: Const { ty: extern "rust-call" fn(fn() {f}, ()) -> <fn() {f} as FnOnce<()>>::Output {<fn() {f} as FnOnce<()>>::call_once}, val: Value(<ZST>) }
}
bb1: {
+ StorageDead(_5); // scope 3 at $DIR/inline_cycle.rs:59:12: 59:13
+ StorageDead(_4); // scope 1 at $DIR/inline_cycle.rs:54:7: 54:8
+ StorageDead(_3); // scope 1 at $DIR/inline_cycle.rs:54:8: 54:9
+ StorageDead(_2); // scope 0 at $DIR/inline_cycle.rs:+1:5: +1:12

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@ -6,21 +6,18 @@
let _1: (); // in scope 0 at $DIR/inline_cycle_generic.rs:+1:5: +1:24
+ scope 1 (inlined <C as Call>::call) { // at $DIR/inline_cycle_generic.rs:9:5: 9:24
+ scope 2 (inlined <B<A> as Call>::call) { // at $DIR/inline_cycle_generic.rs:38:9: 38:31
+ scope 3 (inlined <A as Call>::call) { // at $DIR/inline_cycle_generic.rs:31:9: 31:28
+ scope 4 (inlined <B<C> as Call>::call) { // at $DIR/inline_cycle_generic.rs:23:9: 23:31
+ }
+ }
+ }
+ }
bb0: {
StorageLive(_1); // scope 0 at $DIR/inline_cycle_generic.rs:+1:5: +1:24
- _1 = <C as Call>::call() -> bb1; // scope 0 at $DIR/inline_cycle_generic.rs:+1:5: +1:24
+ _1 = <C as Call>::call() -> bb1; // scope 4 at $DIR/inline_cycle_generic.rs:31:9: 31:28
+ _1 = <A as Call>::call() -> bb1; // scope 2 at $DIR/inline_cycle_generic.rs:31:9: 31:28
// mir::Constant
- // + span: $DIR/inline_cycle_generic.rs:9:5: 9:22
- // + literal: Const { ty: fn() {<C as Call>::call}, val: Value(<ZST>) }
+ // + span: $DIR/inline_cycle_generic.rs:31:9: 31:26
// + literal: Const { ty: fn() {<C as Call>::call}, val: Value(<ZST>) }
+ // + literal: Const { ty: fn() {<A as Call>::call}, val: Value(<ZST>) }
}
bb1: {

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@ -19,14 +19,6 @@
+ scope 3 {
+ debug b => _9; // in scope 3 at $DIR/inline_diverging.rs:28:9: 28:10
+ }
+ scope 6 (inlined <fn() -> ! {sleep} as Fn<()>>::call - shim(fn() -> ! {sleep})) { // at $DIR/inline_diverging.rs:28:13: 28:16
+ scope 7 (inlined sleep) { // at $SRC_DIR/core/src/ops/function.rs:LL:COL
+ }
+ }
+ }
+ scope 4 (inlined <fn() -> ! {sleep} as Fn<()>>::call - shim(fn() -> ! {sleep})) { // at $DIR/inline_diverging.rs:27:13: 27:16
+ scope 5 (inlined sleep) { // at $SRC_DIR/core/src/ops/function.rs:LL:COL
+ }
+ }
+ }
@ -46,11 +38,51 @@
+ StorageLive(_4); // scope 1 at $DIR/inline_diverging.rs:27:13: 27:14
+ _4 = &_2; // scope 1 at $DIR/inline_diverging.rs:27:13: 27:14
+ StorageLive(_5); // scope 1 at $DIR/inline_diverging.rs:27:13: 27:16
+ goto -> bb1; // scope 5 at $DIR/inline_diverging.rs:39:5: 39:12
+ _3 = <fn() -> ! {sleep} as Fn<()>>::call(move _4, move _5) -> [return: bb1, unwind: bb5]; // scope 1 at $DIR/inline_diverging.rs:27:13: 27:16
+ // mir::Constant
+ // + span: $DIR/inline_diverging.rs:27:13: 27:14
+ // + literal: Const { ty: for<'a> extern "rust-call" fn(&'a fn() -> ! {sleep}, ()) -> <fn() -> ! {sleep} as FnOnce<()>>::Output {<fn() -> ! {sleep} as Fn<()>>::call}, val: Value(<ZST>) }
+ }
+
+ bb1: {
+ goto -> bb1; // scope 5 at $DIR/inline_diverging.rs:39:5: 39:12
+ StorageDead(_5); // scope 1 at $DIR/inline_diverging.rs:27:15: 27:16
+ StorageDead(_4); // scope 1 at $DIR/inline_diverging.rs:27:15: 27:16
+ StorageLive(_6); // scope 2 at $DIR/inline_diverging.rs:28:13: 28:14
+ _6 = &_2; // scope 2 at $DIR/inline_diverging.rs:28:13: 28:14
+ StorageLive(_7); // scope 2 at $DIR/inline_diverging.rs:28:13: 28:16
+ _9 = <fn() -> ! {sleep} as Fn<()>>::call(move _6, move _7) -> [return: bb2, unwind: bb4]; // scope 2 at $DIR/inline_diverging.rs:28:13: 28:16
+ // mir::Constant
+ // + span: $DIR/inline_diverging.rs:28:13: 28:14
+ // + literal: Const { ty: for<'a> extern "rust-call" fn(&'a fn() -> ! {sleep}, ()) -> <fn() -> ! {sleep} as FnOnce<()>>::Output {<fn() -> ! {sleep} as Fn<()>>::call}, val: Value(<ZST>) }
+ }
+
+ bb2: {
+ StorageDead(_7); // scope 2 at $DIR/inline_diverging.rs:28:15: 28:16
+ StorageDead(_6); // scope 2 at $DIR/inline_diverging.rs:28:15: 28:16
+ StorageLive(_8); // scope 3 at $DIR/inline_diverging.rs:29:6: 29:7
+ _8 = move _3; // scope 3 at $DIR/inline_diverging.rs:29:6: 29:7
+ Deinit(_1); // scope 3 at $DIR/inline_diverging.rs:29:5: 29:11
+ (_1.0: !) = move _8; // scope 3 at $DIR/inline_diverging.rs:29:5: 29:11
+ (_1.1: !) = move _9; // scope 3 at $DIR/inline_diverging.rs:29:5: 29:11
+ StorageDead(_8); // scope 3 at $DIR/inline_diverging.rs:29:10: 29:11
+ StorageDead(_3); // scope 1 at $DIR/inline_diverging.rs:30:1: 30:2
+ drop(_2) -> bb3; // scope 1 at $DIR/inline_diverging.rs:30:1: 30:2
+ }
+
+ bb3: {
+ unreachable; // scope 0 at $DIR/inline_diverging.rs:30:2: 30:2
+ }
+
+ bb4 (cleanup): {
+ drop(_3) -> bb5; // scope 1 at $DIR/inline_diverging.rs:30:1: 30:2
+ }
+
+ bb5 (cleanup): {
+ drop(_2) -> bb6; // scope 1 at $DIR/inline_diverging.rs:30:1: 30:2
+ }
+
+ bb6 (cleanup): {
+ resume; // scope 1 at $DIR/inline_diverging.rs:26:1: 30:2
}
}

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@ -22,9 +22,6 @@
let mut _18: i32; // in scope 8 at $SRC_DIR/core/src/result.rs:LL:COL
scope 9 {
debug e => _16; // in scope 9 at $SRC_DIR/core/src/result.rs:LL:COL
scope 10 (inlined <i32 as From<i32>>::from) { // at $SRC_DIR/core/src/result.rs:LL:COL
debug t => _18; // in scope 10 at $SRC_DIR/core/src/convert/mod.rs:LL:COL
}
}
}
}
@ -95,18 +92,11 @@
StorageLive(_17); // scope 9 at $SRC_DIR/core/src/result.rs:LL:COL
StorageLive(_18); // scope 9 at $SRC_DIR/core/src/result.rs:LL:COL
_18 = move _16; // scope 9 at $SRC_DIR/core/src/result.rs:LL:COL
_17 = move _18; // scope 10 at $SRC_DIR/core/src/convert/mod.rs:LL:COL
StorageDead(_18); // scope 9 at $SRC_DIR/core/src/result.rs:LL:COL
Deinit(_0); // scope 9 at $SRC_DIR/core/src/result.rs:LL:COL
((_0 as Err).0: i32) = move _17; // scope 9 at $SRC_DIR/core/src/result.rs:LL:COL
discriminant(_0) = 1; // scope 9 at $SRC_DIR/core/src/result.rs:LL:COL
StorageDead(_17); // scope 9 at $SRC_DIR/core/src/result.rs:LL:COL
StorageDead(_16); // scope 8 at $SRC_DIR/core/src/result.rs:LL:COL
StorageDead(_8); // scope 2 at $DIR/separate_const_switch.rs:+1:9: +1:10
StorageDead(_6); // scope 0 at $DIR/separate_const_switch.rs:+1:9: +1:10
StorageDead(_2); // scope 0 at $DIR/separate_const_switch.rs:+1:10: +1:11
StorageDead(_3); // scope 0 at $DIR/separate_const_switch.rs:+2:1: +2:2
return; // scope 0 at $DIR/separate_const_switch.rs:+2:2: +2:2
- _17 = <i32 as From<i32>>::from(move _18) -> bb8; // scope 9 at $SRC_DIR/core/src/result.rs:LL:COL
+ _17 = <i32 as From<i32>>::from(move _18) -> bb7; // scope 9 at $SRC_DIR/core/src/result.rs:LL:COL
// mir::Constant
// + span: $SRC_DIR/core/src/result.rs:LL:COL
// + literal: Const { ty: fn(i32) -> i32 {<i32 as From<i32>>::from}, val: Value(<ZST>) }
}
- bb5: {
@ -152,5 +142,20 @@
+ _5 = discriminant(_3); // scope 0 at $DIR/separate_const_switch.rs:+1:8: +1:10
+ switchInt(move _5) -> [0_isize: bb1, 1_isize: bb3, otherwise: bb2]; // scope 0 at $DIR/separate_const_switch.rs:+1:8: +1:10
}
- bb8: {
+ bb7: {
StorageDead(_18); // scope 9 at $SRC_DIR/core/src/result.rs:LL:COL
Deinit(_0); // scope 9 at $SRC_DIR/core/src/result.rs:LL:COL
((_0 as Err).0: i32) = move _17; // scope 9 at $SRC_DIR/core/src/result.rs:LL:COL
discriminant(_0) = 1; // scope 9 at $SRC_DIR/core/src/result.rs:LL:COL
StorageDead(_17); // scope 9 at $SRC_DIR/core/src/result.rs:LL:COL
StorageDead(_16); // scope 8 at $SRC_DIR/core/src/result.rs:LL:COL
StorageDead(_8); // scope 2 at $DIR/separate_const_switch.rs:+1:9: +1:10
StorageDead(_6); // scope 0 at $DIR/separate_const_switch.rs:+1:9: +1:10
StorageDead(_2); // scope 0 at $DIR/separate_const_switch.rs:+1:10: +1:11
StorageDead(_3); // scope 0 at $DIR/separate_const_switch.rs:+2:1: +2:2
return; // scope 0 at $DIR/separate_const_switch.rs:+2:2: +2:2
}
}