diff --git a/compiler/rustc_codegen_cranelift/src/constant.rs b/compiler/rustc_codegen_cranelift/src/constant.rs index 5478caee57d..077f33bb99c 100644 --- a/compiler/rustc_codegen_cranelift/src/constant.rs +++ b/compiler/rustc_codegen_cranelift/src/constant.rs @@ -38,22 +38,8 @@ impl ConstantCx { pub(crate) fn check_constants(fx: &mut FunctionCx<'_, '_, '_>) -> bool { let mut all_constants_ok = true; for constant in &fx.mir.required_consts { - let unevaluated = match fx.monomorphize(constant.literal) { - ConstantKind::Ty(_) => unreachable!(), - ConstantKind::Unevaluated(uv, _) => uv, - ConstantKind::Val(..) => continue, - }; - - if let Err(err) = fx.tcx.const_eval_resolve(ParamEnv::reveal_all(), unevaluated, None) { + if eval_mir_constant(fx, constant).is_none() { all_constants_ok = false; - match err { - ErrorHandled::Reported(_) => { - fx.tcx.sess.span_err(constant.span, "erroneous constant encountered"); - } - ErrorHandled::TooGeneric => { - span_bug!(constant.span, "codegen encountered polymorphic constant: {:?}", err); - } - } } } all_constants_ok @@ -80,15 +66,15 @@ pub(crate) fn codegen_tls_ref<'tcx>( } pub(crate) fn eval_mir_constant<'tcx>( - fx: &mut FunctionCx<'_, '_, 'tcx>, + fx: &FunctionCx<'_, '_, 'tcx>, constant: &Constant<'tcx>, -) -> (ConstValue<'tcx>, Ty<'tcx>) { +) -> Option<(ConstValue<'tcx>, Ty<'tcx>)> { let constant_kind = fx.monomorphize(constant.literal); let uv = match constant_kind { ConstantKind::Ty(const_) => match const_.kind() { ty::ConstKind::Unevaluated(uv) => uv.expand(), ty::ConstKind::Value(val) => { - return (fx.tcx.valtree_to_const_val((const_.ty(), val)), const_.ty()); + return Some((fx.tcx.valtree_to_const_val((const_.ty(), val)), const_.ty())); } err => span_bug!( constant.span, @@ -102,22 +88,31 @@ pub(crate) fn eval_mir_constant<'tcx>( span_bug!(constant.span, "MIR constant refers to static"); } ConstantKind::Unevaluated(uv, _) => uv, - ConstantKind::Val(val, _) => return (val, constant_kind.ty()), + ConstantKind::Val(val, _) => return Some((val, constant_kind.ty())), }; - ( - fx.tcx.const_eval_resolve(ty::ParamEnv::reveal_all(), uv, None).unwrap_or_else(|_err| { - span_bug!(constant.span, "erroneous constant not captured by required_consts"); - }), - constant_kind.ty(), - ) + let val = fx + .tcx + .const_eval_resolve(ty::ParamEnv::reveal_all(), uv, None) + .map_err(|err| match err { + ErrorHandled::Reported(_) => { + fx.tcx.sess.span_err(constant.span, "erroneous constant encountered"); + } + ErrorHandled::TooGeneric => { + span_bug!(constant.span, "codegen encountered polymorphic constant: {:?}", err); + } + }) + .ok(); + val.map(|val| (val, constant_kind.ty())) } pub(crate) fn codegen_constant_operand<'tcx>( fx: &mut FunctionCx<'_, '_, 'tcx>, constant: &Constant<'tcx>, ) -> CValue<'tcx> { - let (const_val, ty) = eval_mir_constant(fx, constant); + let (const_val, ty) = eval_mir_constant(fx, constant).unwrap_or_else(|| { + span_bug!(constant.span, "erroneous constant not captured by required_consts") + }); codegen_const_value(fx, const_val, ty) } @@ -453,20 +448,13 @@ fn define_all_allocs(tcx: TyCtxt<'_>, module: &mut dyn Module, cx: &mut Constant assert!(cx.todo.is_empty(), "{:?}", cx.todo); } +/// Used only for intrinsic implementations that need a compile-time constant pub(crate) fn mir_operand_get_const_val<'tcx>( fx: &FunctionCx<'_, '_, 'tcx>, operand: &Operand<'tcx>, ) -> Option> { match operand { - Operand::Constant(const_) => match fx.monomorphize(const_.literal) { - ConstantKind::Ty(const_) => Some( - const_.eval_for_mir(fx.tcx, ParamEnv::reveal_all()).try_to_value(fx.tcx).unwrap(), - ), - ConstantKind::Val(val, _) => Some(val), - ConstantKind::Unevaluated(uv, _) => { - Some(fx.tcx.const_eval_resolve(ParamEnv::reveal_all(), uv, None).unwrap()) - } - }, + Operand::Constant(const_) => Some(eval_mir_constant(fx, const_).unwrap().0), // FIXME(rust-lang/rust#85105): Casts like `IMM8 as u32` result in the const being stored // inside a temporary before being passed to the intrinsic requiring the const argument. // This code tries to find a single constant defining definition of the referenced local. diff --git a/compiler/rustc_codegen_ssa/src/mir/constant.rs b/compiler/rustc_codegen_ssa/src/mir/constant.rs index 4c6ab457c49..53ff3c24096 100644 --- a/compiler/rustc_codegen_ssa/src/mir/constant.rs +++ b/compiler/rustc_codegen_ssa/src/mir/constant.rs @@ -42,7 +42,14 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> { }; self.cx.tcx().const_eval_resolve(ty::ParamEnv::reveal_all(), uv, None).map_err(|err| { - self.cx.tcx().sess.span_err(constant.span, "erroneous constant encountered"); + match err { + ErrorHandled::Reported(_) => { + self.cx.tcx().sess.span_err(constant.span, "erroneous constant encountered"); + } + ErrorHandled::TooGeneric => { + span_bug!(constant.span, "codegen encountered polymorphic constant: {:?}", err); + } + } err }) } diff --git a/compiler/rustc_middle/src/ty/consts.rs b/compiler/rustc_middle/src/ty/consts.rs index 37153a63944..9a58a196ed7 100644 --- a/compiler/rustc_middle/src/ty/consts.rs +++ b/compiler/rustc_middle/src/ty/consts.rs @@ -1,5 +1,4 @@ use crate::mir::interpret::LitToConstInput; -use crate::mir::ConstantKind; use crate::ty::{self, DefIdTree, InternalSubsts, ParamEnv, ParamEnvAnd, Ty, TyCtxt}; use rustc_data_structures::intern::Interned; use rustc_hir as hir; @@ -230,20 +229,6 @@ impl<'tcx> Const<'tcx> { } } - #[inline] - /// Tries to evaluate the constant if it is `Unevaluated` and creates a ConstValue if the - /// evaluation succeeds. If it doesn't succeed, returns the unevaluated constant. - pub fn eval_for_mir(self, tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx>) -> ConstantKind<'tcx> { - if let Some(val) = self.kind().try_eval_for_mir(tcx, param_env) { - match val { - Ok(const_val) => ConstantKind::from_value(const_val, self.ty()), - Err(guar) => ConstantKind::Ty(tcx.const_error_with_guaranteed(self.ty(), guar)), - } - } else { - ConstantKind::Ty(self) - } - } - #[inline] /// Panics if the value cannot be evaluated or doesn't contain a valid integer of the given type. pub fn eval_bits(self, tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx>, ty: Ty<'tcx>) -> u128 {