diff --git a/compiler/rustc_mir_transform/src/inline.rs b/compiler/rustc_mir_transform/src/inline.rs
index 12f955d46bd31..8c3eefdeb825a 100644
--- a/compiler/rustc_mir_transform/src/inline.rs
+++ b/compiler/rustc_mir_transform/src/inline.rs
@@ -42,19 +42,7 @@ struct CallSite<'tcx> {
impl<'tcx> MirPass<'tcx> for Inline {
fn is_enabled(&self, sess: &rustc_session::Session) -> bool {
- if let Some(enabled) = sess.opts.unstable_opts.inline_mir {
- return enabled;
- }
-
- match sess.mir_opt_level() {
- 0 | 1 => false,
- 2 => {
- (sess.opts.optimize == OptLevel::Default
- || sess.opts.optimize == OptLevel::Aggressive)
- && sess.opts.incremental == None
- }
- _ => true,
- }
+ InlinerConfig::new(sess).is_ok()
}
fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
@@ -69,6 +57,67 @@ impl<'tcx> MirPass<'tcx> for Inline {
}
}
+impl Inline {
+ pub fn is_enabled_and_needs_mir_inliner_callees(sess: &rustc_session::Session) -> bool {
+ match InlinerConfig::new(sess) {
+ Ok(config) => config.inline_local_fns,
+ Err(_) => false,
+ }
+ }
+}
+
+struct InlinerConfig {
+ /// Inline functions with `#[inline(always)]` attribute
+ inline_fns_with_inline_always_hint: bool,
+ /// Inline functions with `#[inline]` attribute
+ inline_fns_with_inline_hint: bool,
+ /// Inline functions without `#[inline]` attribute
+ /// Inline functions with `#[inline(always)]` attribute
+ inline_fns_without_hint: bool,
+ /// Inline function from current crate (much heavier during incremental compilation)
+ inline_local_fns: bool,
+}
+
+impl InlinerConfig {
+ fn new(sess: &rustc_session::Session) -> Result<InlinerConfig, InliningIsDisabled> {
+ match sess.opts.unstable_opts.inline_mir {
+ Some(true) => return Ok(InlinerConfig::full()),
+ Some(false) => return Err(InliningIsDisabled),
+ None => {}
+ }
+ match sess.mir_opt_level() {
+ 0 | 1 => Err(InliningIsDisabled),
+ 2 => {
+ let optimize = sess.opts.optimize;
+ if optimize == OptLevel::Default || optimize == OptLevel::Aggressive {
+ let is_non_incremental = sess.opts.incremental == None;
+ Ok(InlinerConfig {
+ inline_fns_with_inline_always_hint: true,
+ inline_fns_with_inline_hint: is_non_incremental,
+ inline_fns_without_hint: is_non_incremental,
+ inline_local_fns: is_non_incremental,
+ })
+ } else {
+ Err(InliningIsDisabled)
+ }
+ }
+ _ => Ok(InlinerConfig::full()),
+ }
+ }
+
+ fn full() -> InlinerConfig {
+ InlinerConfig {
+ inline_fns_with_inline_always_hint: true,
+ inline_fns_with_inline_hint: true,
+ inline_fns_without_hint: true,
+ inline_local_fns: true,
+ }
+ }
+}
+
+#[derive(Debug)]
+struct InliningIsDisabled;
+
fn inline<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) -> bool {
let def_id = body.source.def_id().expect_local();
@@ -91,6 +140,7 @@ fn inline<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) -> bool {
let mut this = Inliner {
tcx,
param_env,
+ config: InlinerConfig::new(tcx.sess).unwrap_or_else(|_| InlinerConfig::full()),
codegen_fn_attrs: tcx.codegen_fn_attrs(def_id),
history: Vec::new(),
changed: false,
@@ -103,6 +153,7 @@ fn inline<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) -> bool {
struct Inliner<'tcx> {
tcx: TyCtxt<'tcx>,
param_env: ParamEnv<'tcx>,
+ config: InlinerConfig,
/// Caller codegen attributes.
codegen_fn_attrs: &'tcx CodegenFnAttrs,
/// Stack of inlined instances.
@@ -352,11 +403,35 @@ impl<'tcx> Inliner<'tcx> {
if let InlineAttr::Never = callee_attrs.inline {
return Err("never inline hint");
}
+ match callee_attrs.inline {
+ InlineAttr::Never => return Err("never inline hint"),
+ InlineAttr::Always => {
+ if !self.config.inline_fns_with_inline_always_hint {
+ return Err("inliner is configured to ignore #[inline(always)] functions");
+ }
+ }
+ InlineAttr::Hint => {
+ if !self.config.inline_fns_with_inline_hint {
+ return Err("inliner is configured to ignore #[inline] functions");
+ }
+ }
+ _ => {
+ if !self.config.inline_fns_without_hint {
+ return Err("inliner is configured to ignore functions without #[inline]");
+ }
+ }
+ }
+
+ let callee_is_local = callsite.callee.def_id().is_local();
+
+ if callee_is_local && !self.config.inline_local_fns {
+ return Err("inliner is configured to ignore local functions");
+ }
// Only inline local functions if they would be eligible for cross-crate
// inlining. This is to ensure that the final crate doesn't have MIR that
// reference unexported symbols
- if callsite.callee.def_id().is_local() {
+ if callee_is_local {
let is_generic = callsite.callee.substs.non_erasable_generics().next().is_some();
if !is_generic && !callee_attrs.requests_inline() {
return Err("not exported");
diff --git a/compiler/rustc_mir_transform/src/lib.rs b/compiler/rustc_mir_transform/src/lib.rs
index 65864dc016f4f..c76d8e9edf16b 100644
--- a/compiler/rustc_mir_transform/src/lib.rs
+++ b/compiler/rustc_mir_transform/src/lib.rs
@@ -388,7 +388,7 @@ fn mir_drops_elaborated_and_const_checked(tcx: TyCtxt<'_>, def: LocalDefId) -> &
let is_fn_like = tcx.def_kind(def).is_fn_like();
if is_fn_like {
// Do not compute the mir call graph without said call graph actually being used.
- if inline::Inline.is_enabled(&tcx.sess) {
+ if inline::Inline::is_enabled_and_needs_mir_inliner_callees(&tcx.sess) {
tcx.ensure_with_value().mir_inliner_callees(ty::InstanceDef::Item(def.to_def_id()));
}
}
diff --git a/tests/codegen-units/partitioning/inlining-from-extern-crate.rs b/tests/codegen-units/partitioning/inlining-from-extern-crate.rs
index 1cc21632e4818..6ebe8aee6b7e9 100644
--- a/tests/codegen-units/partitioning/inlining-from-extern-crate.rs
+++ b/tests/codegen-units/partitioning/inlining-from-extern-crate.rs
@@ -4,6 +4,7 @@
// incremental
// compile-flags:-Zprint-mono-items=lazy
// compile-flags:-Zinline-in-all-cgus
+// compile-flags:-Zinline_mir=false
#![crate_type="lib"]
diff --git a/tests/incremental/hashes/function_interfaces.rs b/tests/incremental/hashes/function_interfaces.rs
index 182ca7d926c6b..23b81705f9aa0 100644
--- a/tests/incremental/hashes/function_interfaces.rs
+++ b/tests/incremental/hashes/function_interfaces.rs
@@ -302,7 +302,7 @@ pub fn return_impl_trait() -> i32 {
}
#[cfg(not(any(cfail1,cfail4)))]
-#[rustc_clean(cfg = "cfail2", except = "hir_owner, hir_owner_nodes, typeck, fn_sig, optimized_mir")]
+#[rustc_clean(cfg = "cfail2", except = "hir_owner, hir_owner_nodes, typeck, fn_sig")]
#[rustc_clean(cfg = "cfail3")]
#[rustc_clean(cfg = "cfail5", except = "hir_owner, hir_owner_nodes, typeck, fn_sig, optimized_mir")]
#[rustc_clean(cfg = "cfail6")]