From 90c7731f6cca6e4c741c5f465b307b4ac4a7f31f Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?D=C3=A1niel=20Buga?= Date: Wed, 23 Sep 2020 15:54:21 +0200 Subject: [PATCH] Enable const prop into operands at mir_opt_level=2 --- compiler/rustc_mir/src/transform/const_prop.rs | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/compiler/rustc_mir/src/transform/const_prop.rs b/compiler/rustc_mir/src/transform/const_prop.rs index aa88719c26a49..0f04ead94dd33 100644 --- a/compiler/rustc_mir/src/transform/const_prop.rs +++ b/compiler/rustc_mir/src/transform/const_prop.rs @@ -1046,9 +1046,9 @@ impl<'mir, 'tcx> MutVisitor<'tcx> for ConstPropagator<'mir, 'tcx> { fn visit_operand(&mut self, operand: &mut Operand<'tcx>, location: Location) { self.super_operand(operand, location); - // Only const prop copies and moves on `mir_opt_level=3` as doing so - // currently increases compile time. - if self.tcx.sess.opts.debugging_opts.mir_opt_level >= 3 { + // Only const prop copies and moves on `mir_opt_level=2` as doing so + // currently slightly increases compile time in some cases. + if self.tcx.sess.opts.debugging_opts.mir_opt_level >= 2 { self.propagate_operand(operand) } } @@ -1246,8 +1246,8 @@ impl<'mir, 'tcx> MutVisitor<'tcx> for ConstPropagator<'mir, 'tcx> { | TerminatorKind::InlineAsm { .. } => {} // Every argument in our function calls have already been propagated in `visit_operand`. // - // NOTE: because LLVM codegen gives performance regressions with it, so this is gated - // on `mir_opt_level=3`. + // NOTE: because LLVM codegen gives slight performance regressions with it, so this is + // gated on `mir_opt_level=2`. TerminatorKind::Call { .. } => {} }