diff options
Diffstat (limited to 'compiler/rustc_mir/src/transform')
| -rw-r--r-- | compiler/rustc_mir/src/transform/inline.rs | 137 |
1 files changed, 60 insertions, 77 deletions
diff --git a/compiler/rustc_mir/src/transform/inline.rs b/compiler/rustc_mir/src/transform/inline.rs index 944f41c61a2..010a7470ccd 100644 --- a/compiler/rustc_mir/src/transform/inline.rs +++ b/compiler/rustc_mir/src/transform/inline.rs @@ -93,96 +93,79 @@ impl Inliner<'tcx> { return; } - let mut local_change; let mut changed = false; + while let Some(callsite) = callsites.pop_front() { + debug!("checking whether to inline callsite {:?}", callsite); - loop { - local_change = false; - while let Some(callsite) = callsites.pop_front() { - debug!("checking whether to inline callsite {:?}", callsite); - - if let InstanceDef::Item(_) = callsite.callee.def { - if !self.tcx.is_mir_available(callsite.callee.def_id()) { - debug!( - "checking whether to inline callsite {:?} - MIR unavailable", - callsite, - ); - continue; - } + if let InstanceDef::Item(_) = callsite.callee.def { + if !self.tcx.is_mir_available(callsite.callee.def_id()) { + debug!("checking whether to inline callsite {:?} - MIR unavailable", callsite,); + continue; } + } - let callee_body = if let Some(callee_def_id) = callsite.callee.def_id().as_local() { - let callee_hir_id = self.tcx.hir().local_def_id_to_hir_id(callee_def_id); - // Avoid a cycle here by only using `instance_mir` only if we have - // a lower `HirId` than the callee. This ensures that the callee will - // not inline us. This trick only works without incremental compilation. - // So don't do it if that is enabled. Also avoid inlining into generators, - // since their `optimized_mir` is used for layout computation, which can - // create a cycle, even when no attempt is made to inline the function - // in the other direction. - if !self.tcx.dep_graph.is_fully_enabled() - && self_hir_id < callee_hir_id - && caller_body.generator_kind.is_none() - { - self.tcx.instance_mir(callsite.callee.def) - } else { - continue; - } - } else { - // This cannot result in a cycle since the callee MIR is from another crate - // and is already optimized. + let callee_body = if let Some(callee_def_id) = callsite.callee.def_id().as_local() { + let callee_hir_id = self.tcx.hir().local_def_id_to_hir_id(callee_def_id); + // Avoid a cycle here by only using `instance_mir` only if we have + // a lower `HirId` than the callee. This ensures that the callee will + // not inline us. This trick only works without incremental compilation. + // So don't do it if that is enabled. Also avoid inlining into generators, + // since their `optimized_mir` is used for layout computation, which can + // create a cycle, even when no attempt is made to inline the function + // in the other direction. + if !self.tcx.dep_graph.is_fully_enabled() + && self_hir_id < callee_hir_id + && caller_body.generator_kind.is_none() + { self.tcx.instance_mir(callsite.callee.def) - }; - - let callee_body: &Body<'tcx> = &*callee_body; - - let callee_body = if self.consider_optimizing(callsite, callee_body) { - self.tcx.subst_and_normalize_erasing_regions( - &callsite.callee.substs, - self.param_env, - callee_body, - ) } else { continue; - }; + } + } else { + // This cannot result in a cycle since the callee MIR is from another crate + // and is already optimized. + self.tcx.instance_mir(callsite.callee.def) + }; - // Copy only unevaluated constants from the callee_body into the caller_body. - // Although we are only pushing `ConstKind::Unevaluated` consts to - // `required_consts`, here we may not only have `ConstKind::Unevaluated` - // because we are calling `subst_and_normalize_erasing_regions`. - caller_body.required_consts.extend( - callee_body.required_consts.iter().copied().filter(|&constant| { - matches!(constant.literal.val, ConstKind::Unevaluated(_, _, _)) - }), - ); + let callee_body: &Body<'tcx> = &*callee_body; - let start = caller_body.basic_blocks().len(); - debug!("attempting to inline callsite {:?} - body={:?}", callsite, callee_body); - if !self.inline_call(callsite, caller_body, callee_body) { - debug!("attempting to inline callsite {:?} - failure", callsite); - continue; - } - debug!("attempting to inline callsite {:?} - success", callsite); - - // Add callsites from inlined function - for (bb, bb_data) in caller_body.basic_blocks().iter_enumerated().skip(start) { - if let Some(new_callsite) = - self.get_valid_function_call(bb, bb_data, caller_body) - { - // Don't inline the same function multiple times. - if callsite.callee != new_callsite.callee { - callsites.push_back(new_callsite); - } + let callee_body = if self.consider_optimizing(callsite, callee_body) { + self.tcx.subst_and_normalize_erasing_regions( + &callsite.callee.substs, + self.param_env, + callee_body, + ) + } else { + continue; + }; + + // Copy only unevaluated constants from the callee_body into the caller_body. + // Although we are only pushing `ConstKind::Unevaluated` consts to + // `required_consts`, here we may not only have `ConstKind::Unevaluated` + // because we are calling `subst_and_normalize_erasing_regions`. + caller_body.required_consts.extend(callee_body.required_consts.iter().copied().filter( + |&constant| matches!(constant.literal.val, ConstKind::Unevaluated(_, _, _)), + )); + + let start = caller_body.basic_blocks().len(); + debug!("attempting to inline callsite {:?} - body={:?}", callsite, callee_body); + if !self.inline_call(callsite, caller_body, callee_body) { + debug!("attempting to inline callsite {:?} - failure", callsite); + continue; + } + debug!("attempting to inline callsite {:?} - success", callsite); + + // Add callsites from inlined function + for (bb, bb_data) in caller_body.basic_blocks().iter_enumerated().skip(start) { + if let Some(new_callsite) = self.get_valid_function_call(bb, bb_data, caller_body) { + // Don't inline the same function multiple times. + if callsite.callee != new_callsite.callee { + callsites.push_back(new_callsite); } } - - local_change = true; - changed = true; } - if !local_change { - break; - } + changed = true; } // Simplify if we inlined anything. |