Rollup merge of #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 #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`.

src/tools/clippy/clippy_lints/src/non_copy_const.rs

@@ -290,14 +290,14 @@ impl NonCopyConst {
             promoted: None,
         };
         let param_env = cx.tcx.param_env(def_id).with_reveal_all_normalized(cx.tcx);
-        let result = cx.tcx.const_eval_global_id_for_typeck(param_env, cid, None);
+        let result = cx.tcx.const_eval_global_id_for_typeck(param_env, cid, rustc_span::DUMMY_SP);
         self.is_value_unfrozen_raw(cx, result, ty)
     }
 
     fn is_value_unfrozen_expr<'tcx>(&self, cx: &LateContext<'tcx>, hir_id: HirId, def_id: DefId, ty: Ty<'tcx>) -> bool {
         let args = cx.typeck_results().node_args(hir_id);
 
-        let result = Self::const_eval_resolve(cx.tcx, cx.param_env, ty::UnevaluatedConst::new(def_id, args), None);
+        let result = Self::const_eval_resolve(cx.tcx, cx.param_env, ty::UnevaluatedConst::new(def_id, args), rustc_span::DUMMY_SP);
         self.is_value_unfrozen_raw(cx, result, ty)
     }
 
@@ -305,7 +305,7 @@ impl NonCopyConst {
         tcx: TyCtxt<'tcx>,
         param_env: ty::ParamEnv<'tcx>,
         ct: ty::UnevaluatedConst<'tcx>,
-        span: Option<Span>,
+        span: Span,
     ) -> EvalToValTreeResult<'tcx> {
         match ty::Instance::resolve(tcx, param_env, ct.def, ct.args) {
             Ok(Some(instance)) => {
@@ -315,8 +315,8 @@ impl NonCopyConst {
                 };
                 tcx.const_eval_global_id_for_typeck(param_env, cid, span)
             },
-            Ok(None) => Err(ErrorHandled::TooGeneric(span.unwrap_or(rustc_span::DUMMY_SP))),
-            Err(err) => Err(ErrorHandled::Reported(err.into(), span.unwrap_or(rustc_span::DUMMY_SP))),
+            Ok(None) => Err(ErrorHandled::TooGeneric(span)),
+            Err(err) => Err(ErrorHandled::Reported(err.into(), span)),
         }
     }
 }

src/tools/clippy/clippy_utils/src/consts.rs

@@ -550,7 +550,7 @@ impl<'a, 'tcx> ConstEvalLateContext<'a, 'tcx> {
                 let result = self
                     .lcx
                     .tcx
-                    .const_eval_resolve(self.param_env, mir::UnevaluatedConst::new(def_id, args), None)
+                    .const_eval_resolve(self.param_env, mir::UnevaluatedConst::new(def_id, args), qpath.span())
                     .ok()
                     .map(|val| rustc_middle::mir::Const::from_value(val, ty))?;
                 let result = mir_to_const(self.lcx, result)?;

src/tools/miri/src/machine.rs

@@ -1503,7 +1503,7 @@ impl<'mir, 'tcx> Machine<'mir, 'tcx> for MiriMachine<'mir, 'tcx> {
     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>>
@@ -1511,7 +1511,7 @@ impl<'mir, 'tcx> Machine<'mir, 'tcx> for MiriMachine<'mir, 'tcx> {
         F: Fn(
             &InterpCx<'mir, 'tcx, Self>,
             mir::Const<'tcx>,
-            Option<Span>,
+            Span,
             Option<TyAndLayout<'tcx>>,
         ) -> InterpResult<'tcx, OpTy<'tcx, Self::Provenance>>,
     {

src/tools/miri/src/shims/intrinsics/simd.rs

@@ -549,7 +549,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
 
                 let index = generic_args[2]
                     .expect_const()
-                    .eval(*this.tcx, this.param_env(), Some(this.tcx.span))
+                    .eval(*this.tcx, this.param_env(), this.tcx.span)
                     .unwrap()
                     .unwrap_branch();
                 let index_len = index.len();