diff --git a/src/librustc_mir/transform/const_prop.rs b/src/librustc_mir/transform/const_prop.rs index 51d0ab7943c7..da11a7446bbe 100644 --- a/src/librustc_mir/transform/const_prop.rs +++ b/src/librustc_mir/transform/const_prop.rs @@ -648,8 +648,21 @@ impl<'mir, 'tcx> ConstPropagator<'mir, 'tcx> { } } - fn should_const_prop(&self) -> bool { - self.tcx.sess.opts.debugging_opts.mir_opt_level >= 2 + fn should_const_prop(&mut self, op: OpTy<'tcx>) -> bool { + if self.tcx.sess.opts.debugging_opts.mir_opt_level >= 2 { + return true; + } else if self.tcx.sess.opts.debugging_opts.mir_opt_level == 0 { + return false; + } + + match *op { + interpret::Operand::Immediate(Immediate::Scalar(ScalarMaybeUndef::Scalar(s))) => + s.is_bits(), + interpret::Operand::Immediate(Immediate::ScalarPair(ScalarMaybeUndef::Scalar(l), + ScalarMaybeUndef::Scalar(r))) => + l.is_bits() && r.is_bits(), + _ => false + } } } @@ -749,15 +762,15 @@ impl<'mir, 'tcx> MutVisitor<'tcx> for ConstPropagator<'mir, 'tcx> { if self.can_const_prop[local] { trace!("propagated into {:?}", local); - if self.should_const_prop() { - let value = - self.get_const(local).expect("local was dead/uninitialized"); - trace!("replacing {:?} with {:?}", rval, value); - self.replace_with_const( - rval, - value, - statement.source_info, - ); + if let Some(value) = self.get_const(local) { + if self.should_const_prop(value) { + trace!("replacing {:?} with {:?}", rval, value); + self.replace_with_const( + rval, + value, + statement.source_info, + ); + } } } else { trace!("can't propagate into {:?}", local); @@ -859,7 +872,7 @@ impl<'mir, 'tcx> MutVisitor<'tcx> for ConstPropagator<'mir, 'tcx> { &msg, ); } else { - if self.should_const_prop() { + if self.should_const_prop(value) { if let ScalarMaybeUndef::Scalar(scalar) = value_const { *cond = self.operand_from_scalar( scalar, @@ -872,8 +885,8 @@ impl<'mir, 'tcx> MutVisitor<'tcx> for ConstPropagator<'mir, 'tcx> { } }, TerminatorKind::SwitchInt { ref mut discr, switch_ty, .. } => { - if self.should_const_prop() { - if let Some(value) = self.eval_operand(&discr, source_info) { + if let Some(value) = self.eval_operand(&discr, source_info) { + if self.should_const_prop(value) { if let ScalarMaybeUndef::Scalar(scalar) = self.ecx.read_scalar(value).unwrap() { *discr = self.operand_from_scalar(scalar, switch_ty, source_info.span); diff --git a/src/test/codegen/optimize-attr-1.rs b/src/test/codegen/optimize-attr-1.rs index 4a5b7c05231d..a8be10ba3ce0 100644 --- a/src/test/codegen/optimize-attr-1.rs +++ b/src/test/codegen/optimize-attr-1.rs @@ -8,7 +8,7 @@ // CHECK-LABEL: define i32 @nothing // CHECK-SAME: [[NOTHING_ATTRS:#[0-9]+]] -// NO-OPT: ret i32 %_1.0 +// NO-OPT: ret i32 4 // SIZE-OPT: ret i32 4 // SPEEC-OPT: ret i32 4 #[no_mangle] @@ -18,7 +18,7 @@ pub fn nothing() -> i32 { // CHECK-LABEL: define i32 @size // CHECK-SAME: [[SIZE_ATTRS:#[0-9]+]] -// NO-OPT: ret i32 %_1.0 +// NO-OPT: ret i32 6 // SIZE-OPT: ret i32 6 // SPEED-OPT: ret i32 6 #[optimize(size)] @@ -31,7 +31,7 @@ pub fn size() -> i32 { // NO-OPT-SAME: [[NOTHING_ATTRS]] // SPEED-OPT-SAME: [[NOTHING_ATTRS]] // SIZE-OPT-SAME: [[SPEED_ATTRS:#[0-9]+]] -// NO-OPT: ret i32 %_1.0 +// NO-OPT: ret i32 8 // SIZE-OPT: ret i32 8 // SPEED-OPT: ret i32 8 #[optimize(speed)] diff --git a/src/test/incremental/hashes/while_let_loops.rs b/src/test/incremental/hashes/while_let_loops.rs index 1e628d019196..615f1fe1fd0b 100644 --- a/src/test/incremental/hashes/while_let_loops.rs +++ b/src/test/incremental/hashes/while_let_loops.rs @@ -48,7 +48,7 @@ pub fn change_loop_condition() { } #[cfg(not(cfail1))] -#[rustc_clean(cfg="cfail2", except="HirBody, mir_built, optimized_mir")] +#[rustc_clean(cfg="cfail2", except="HirBody, mir_built")] #[rustc_clean(cfg="cfail3")] pub fn change_loop_condition() { let mut _x = 0; @@ -70,7 +70,7 @@ pub fn add_break() { } #[cfg(not(cfail1))] -#[rustc_clean(cfg="cfail2", except="HirBody, mir_built, optimized_mir, typeck_tables_of")] +#[rustc_clean(cfg="cfail2", except="HirBody, mir_built, typeck_tables_of")] #[rustc_clean(cfg="cfail3")] pub fn add_break() { let mut _x = 0; @@ -141,7 +141,7 @@ pub fn change_break_label() { } #[cfg(not(cfail1))] -#[rustc_clean(cfg="cfail2", except="HirBody, mir_built, optimized_mir")] +#[rustc_clean(cfg="cfail2", except="HirBody, mir_built")] #[rustc_clean(cfg="cfail3")] pub fn change_break_label() { let mut _x = 0; @@ -191,7 +191,7 @@ pub fn change_continue_label() { } #[cfg(not(cfail1))] -#[rustc_clean(cfg="cfail2", except="HirBody, mir_built, optimized_mir")] +#[rustc_clean(cfg="cfail2", except="HirBody, mir_built")] #[rustc_clean(cfg="cfail3")] pub fn change_continue_label() { let mut _x = 0; @@ -216,7 +216,7 @@ pub fn change_continue_to_break() { } #[cfg(not(cfail1))] -#[rustc_clean(cfg="cfail2", except="HirBody, mir_built, optimized_mir")] +#[rustc_clean(cfg="cfail2", except="HirBody, mir_built")] #[rustc_clean(cfg="cfail3")] pub fn change_continue_to_break() { let mut _x = 0; diff --git a/src/test/incremental/hashes/while_loops.rs b/src/test/incremental/hashes/while_loops.rs index 295c2244879f..70d0f86c3d26 100644 --- a/src/test/incremental/hashes/while_loops.rs +++ b/src/test/incremental/hashes/while_loops.rs @@ -48,7 +48,7 @@ pub fn change_loop_condition() { } #[cfg(not(cfail1))] -#[rustc_clean(cfg="cfail2", except="HirBody, mir_built, optimized_mir")] +#[rustc_clean(cfg="cfail2", except="HirBody, mir_built")] #[rustc_clean(cfg="cfail3")] pub fn change_loop_condition() { let mut _x = 0; @@ -191,7 +191,7 @@ pub fn change_continue_label() { } #[cfg(not(cfail1))] -#[rustc_clean(cfg="cfail2", except="HirBody, mir_built, optimized_mir")] +#[rustc_clean(cfg="cfail2", except="HirBody, mir_built")] #[rustc_clean(cfg="cfail3")] pub fn change_continue_label() { let mut _x = 0;