Rollup merge of rust-lang#122480 - oli-obk:const-eval-span-no-opt, r=RalfJung

Avoid various uses of `Option<Span>` in favor of using `DUMMY_SP` in the few cases that used `None`

based on rust-lang#122471

`DUMMY_SP` is already the sentinel value we have that says "no span". We don't need to wrap these `Span`s in a separate `Option`.

Author: matthiaskrgr

compiler/rustc_codegen_cranelift/src/constant.rs

@@ -74,7 +74,7 @@ pub(crate) fn eval_mir_constant<'tcx>(
     let cv = fx.monomorphize(constant.const_);
     // This cannot fail because we checked all required_consts in advance.
     let val = cv
-        .eval(fx.tcx, ty::ParamEnv::reveal_all(), Some(constant.span))
+        .eval(fx.tcx, ty::ParamEnv::reveal_all(), constant.span)
         .expect("erroneous constant missed by mono item collection");
     (val, cv.ty())
 }

compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs

@@ -728,8 +728,10 @@ fn codegen_regular_intrinsic_call<'tcx>(
         | sym::variant_count => {
             intrinsic_args!(fx, args => (); intrinsic);
 
-            let const_val =
-                fx.tcx.const_eval_instance(ParamEnv::reveal_all(), instance, None).unwrap();
+            let const_val = fx
+                .tcx
+                .const_eval_instance(ParamEnv::reveal_all(), instance, source_info.span)
+                .unwrap();
             let val = crate::constant::codegen_const_value(fx, const_val, ret.layout().ty);
             ret.write_cvalue(fx, val);
         }

compiler/rustc_codegen_cranelift/src/intrinsics/simd.rs

@@ -131,7 +131,7 @@ pub(super) fn codegen_simd_intrinsic_call<'tcx>(
 
             let idx = generic_args[2]
                 .expect_const()
-                .eval(fx.tcx, ty::ParamEnv::reveal_all(), Some(span))
+                .eval(fx.tcx, ty::ParamEnv::reveal_all(), span)
                 .unwrap()
                 .unwrap_branch();
 

compiler/rustc_codegen_llvm/src/intrinsic.rs

@@ -1129,7 +1129,7 @@ fn generic_simd_intrinsic<'ll, 'tcx>(
     if name == sym::simd_shuffle_generic {
         let idx = fn_args[2]
             .expect_const()
-            .eval(tcx, ty::ParamEnv::reveal_all(), Some(span))
+            .eval(tcx, ty::ParamEnv::reveal_all(), span)
             .unwrap()
             .unwrap_branch();
         let n = idx.len() as u64;

compiler/rustc_codegen_ssa/src/debuginfo/type_names.rs

@@ -19,6 +19,7 @@ use rustc_hir::{CoroutineDesugaring, CoroutineKind, CoroutineSource, Mutability}
 use rustc_middle::ty::layout::{IntegerExt, TyAndLayout};
 use rustc_middle::ty::{self, ExistentialProjection, ParamEnv, Ty, TyCtxt};
 use rustc_middle::ty::{GenericArgKind, GenericArgsRef};
+use rustc_span::DUMMY_SP;
 use rustc_target::abi::Integer;
 use smallvec::SmallVec;
 
@@ -704,7 +705,7 @@ fn push_const_param<'tcx>(tcx: TyCtxt<'tcx>, ct: ty::Const<'tcx>, output: &mut S
                 // avoiding collisions and will make the emitted type names shorter.
                 let hash_short = tcx.with_stable_hashing_context(|mut hcx| {
                     let mut hasher = StableHasher::new();
-                    let ct = ct.eval(tcx, ty::ParamEnv::reveal_all(), None).unwrap();
+                    let ct = ct.eval(tcx, ty::ParamEnv::reveal_all(), DUMMY_SP).unwrap();
                     hcx.while_hashing_spans(false, |hcx| ct.hash_stable(hcx, &mut hasher));
                     hasher.finish::<Hash64>()
                 });

compiler/rustc_codegen_ssa/src/mir/constant.rs

@@ -24,7 +24,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
         // `MirUsedCollector` visited all required_consts before codegen began, so if we got here
         // there can be no more constants that fail to evaluate.
         self.monomorphize(constant.const_)
-            .eval(self.cx.tcx(), ty::ParamEnv::reveal_all(), Some(constant.span))
+            .eval(self.cx.tcx(), ty::ParamEnv::reveal_all(), constant.span)
             .expect("erroneous constant missed by mono item collection")
     }
 
@@ -56,11 +56,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
             other => span_bug!(constant.span, "{other:#?}"),
         };
         let uv = self.monomorphize(uv);
-        self.cx.tcx().const_eval_resolve_for_typeck(
-            ty::ParamEnv::reveal_all(),
-            uv,
-            Some(constant.span),
-        )
+        self.cx.tcx().const_eval_resolve_for_typeck(ty::ParamEnv::reveal_all(), uv, constant.span)
     }
 
     /// process constant containing SIMD shuffle indices

compiler/rustc_codegen_ssa/src/mir/intrinsic.rs

@@ -130,7 +130,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
             | sym::variant_count => {
                 let value = bx
                     .tcx()
-                    .const_eval_instance(ty::ParamEnv::reveal_all(), instance, None)
+                    .const_eval_instance(ty::ParamEnv::reveal_all(), instance, span)
                     .unwrap();
                 OperandRef::from_const(bx, value, ret_ty).immediate_or_packed_pair(bx)
             }

compiler/rustc_const_eval/src/interpret/eval_context.rs

@@ -826,7 +826,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
             for &const_ in &body.required_consts {
                 let c = self
                     .instantiate_from_current_frame_and_normalize_erasing_regions(const_.const_)?;
-                c.eval(*self.tcx, self.param_env, Some(const_.span)).map_err(|err| {
+                c.eval(*self.tcx, self.param_env, const_.span).map_err(|err| {
                     err.emit_note(*self.tcx);
                     err
                 })?;
@@ -1174,7 +1174,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
     pub fn eval_mir_constant(
         &self,
         val: &mir::Const<'tcx>,
-        span: Option<Span>,
+        span: Span,
         layout: Option<TyAndLayout<'tcx>>,
     ) -> InterpResult<'tcx, OpTy<'tcx, M::Provenance>> {
         M::eval_mir_constant(self, *val, span, layout, |ecx, val, span, layout| {

compiler/rustc_const_eval/src/interpret/intrinsics.rs

@@ -153,9 +153,8 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
                     sym::type_name => Ty::new_static_str(self.tcx.tcx),
                     _ => bug!(),
                 };
-                let val = self.ctfe_query(|tcx| {
-                    tcx.const_eval_global_id(self.param_env, gid, Some(tcx.span))
-                })?;
+                let val =
+                    self.ctfe_query(|tcx| tcx.const_eval_global_id(self.param_env, gid, tcx.span))?;
                 let val = self.const_val_to_op(val, ty, Some(dest.layout))?;
                 self.copy_op(&val, dest)?;
             }

compiler/rustc_const_eval/src/interpret/machine.rs

@@ -525,15 +525,15 @@ pub trait Machine<'mir, 'tcx: 'mir>: Sized {
     fn eval_mir_constant<F>(
         ecx: &InterpCx<'mir, 'tcx, Self>,
         val: mir::Const<'tcx>,
-        span: Option<Span>,
+        span: Span,
         layout: Option<TyAndLayout<'tcx>>,
         eval: F,
     ) -> InterpResult<'tcx, OpTy<'tcx, Self::Provenance>>
     where
         F: Fn(
             &InterpCx<'mir, 'tcx, Self>,
             mir::Const<'tcx>,
-            Option<Span>,
+            Span,
             Option<TyAndLayout<'tcx>>,
         ) -> InterpResult<'tcx, OpTy<'tcx, Self::Provenance>>,
     {