use TypingEnv when no infcx is available

the behavior of the type system not only depends on the current
assumptions, but also the currentnphase of the compiler. This is
mostly necessary as we need to decide whether and how to reveal
opaque types. We track this via the `TypingMode`.

compiler/rustc_codegen_ssa/src/mir/block.rs

@@ -777,7 +777,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
 
             let do_panic = !bx
                 .tcx()
-                .check_validity_requirement((requirement, bx.param_env().and(ty)))
+                .check_validity_requirement((requirement, bx.typing_env().as_query_input(ty)))
                 .expect("expect to have layout during codegen");
 
             let layout = bx.layout_of(ty);
@@ -848,14 +848,8 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
         let (instance, mut llfn) = match *callee.layout.ty.kind() {
             ty::FnDef(def_id, args) => (
                 Some(
-                    ty::Instance::expect_resolve(
-                        bx.tcx(),
-                        ty::ParamEnv::reveal_all(),
-                        def_id,
-                        args,
-                        fn_span,
-                    )
-                    .polymorphize(bx.tcx()),
+                    ty::Instance::expect_resolve(bx.tcx(), bx.typing_env(), def_id, args, fn_span)
+                        .polymorphize(bx.tcx()),
                 ),
                 None,
             ),
@@ -1191,7 +1185,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                     if let ty::FnDef(def_id, args) = *const_.ty().kind() {
                         let instance = ty::Instance::resolve_for_fn_ptr(
                             bx.tcx(),
-                            ty::ParamEnv::reveal_all(),
+                            bx.typing_env(),
                             def_id,
                             args,
                         )

compiler/rustc_codegen_ssa/src/mir/constant.rs

@@ -1,6 +1,6 @@
 use rustc_abi::BackendRepr;
 use rustc_middle::mir::interpret::ErrorHandled;
-use rustc_middle::ty::layout::HasTyCtxt;
+use rustc_middle::ty::layout::{HasTyCtxt, HasTypingEnv};
 use rustc_middle::ty::{self, Ty};
 use rustc_middle::{bug, mir, span_bug};
 
@@ -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(), constant.span)
+            .eval(self.cx.tcx(), self.cx.typing_env(), constant.span)
             .expect("erroneous constant missed by mono item collection")
     }
 
@@ -57,7 +57,7 @@ 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, constant.span)
+        self.cx.tcx().const_eval_resolve_for_typeck(self.cx.typing_env(), uv, constant.span)
     }
 
     /// process constant containing SIMD shuffle indices & constant vectors

compiler/rustc_codegen_ssa/src/mir/intrinsic.rs

@@ -59,14 +59,14 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
         llresult: Bx::Value,
         span: Span,
     ) -> Result<(), ty::Instance<'tcx>> {
-        let callee_ty = instance.ty(bx.tcx(), ty::ParamEnv::reveal_all());
+        let callee_ty = instance.ty(bx.tcx(), bx.typing_env());
 
         let ty::FnDef(def_id, fn_args) = *callee_ty.kind() else {
             bug!("expected fn item type, found {}", callee_ty);
         };
 
         let sig = callee_ty.fn_sig(bx.tcx());
-        let sig = bx.tcx().normalize_erasing_late_bound_regions(ty::ParamEnv::reveal_all(), sig);
+        let sig = bx.tcx().normalize_erasing_late_bound_regions(bx.typing_env(), sig);
         let arg_tys = sig.inputs();
         let ret_ty = sig.output();
         let name = bx.tcx().item_name(def_id);

compiler/rustc_codegen_ssa/src/mir/mod.rs

@@ -4,7 +4,7 @@ use rustc_index::IndexVec;
 use rustc_index::bit_set::BitSet;
 use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrFlags;
 use rustc_middle::mir::{UnwindTerminateReason, traversal};
-use rustc_middle::ty::layout::{FnAbiOf, HasTyCtxt, TyAndLayout};
+use rustc_middle::ty::layout::{FnAbiOf, HasTyCtxt, HasTypingEnv, TyAndLayout};
 use rustc_middle::ty::{self, Instance, Ty, TyCtxt, TypeFoldable, TypeVisitableExt};
 use rustc_middle::{bug, mir, span_bug};
 use rustc_target::callconv::{FnAbi, PassMode};
@@ -128,7 +128,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
         debug!("monomorphize: self.instance={:?}", self.instance);
         self.instance.instantiate_mir_and_normalize_erasing_regions(
             self.cx.tcx(),
-            ty::ParamEnv::reveal_all(),
+            self.cx.typing_env(),
             ty::EarlyBinder::bind(value),
         )
     }

compiler/rustc_codegen_ssa/src/mir/rvalue.rs

@@ -474,7 +474,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                             ty::FnDef(def_id, args) => {
                                 let instance = ty::Instance::resolve_for_fn_ptr(
                                     bx.tcx(),
-                                    ty::ParamEnv::reveal_all(),
+                                    bx.typing_env(),
                                     def_id,
                                     args,
                                 )
@@ -709,7 +709,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                     mir::NullOp::OffsetOf(fields) => {
                         let val = bx
                             .tcx()
-                            .offset_of_subfield(bx.param_env(), layout, fields.iter())
+                            .offset_of_subfield(bx.typing_env(), layout, fields.iter())
                             .bytes();
                         bx.cx().const_usize(val)
                     }
@@ -727,7 +727,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
 
             mir::Rvalue::ThreadLocalRef(def_id) => {
                 assert!(bx.cx().tcx().is_static(def_id));
-                let layout = bx.layout_of(bx.cx().tcx().static_ptr_ty(def_id));
+                let layout = bx.layout_of(bx.cx().tcx().static_ptr_ty(def_id, bx.typing_env()));
                 let static_ = if !def_id.is_local() && bx.cx().tcx().needs_thread_local_shim(def_id)
                 {
                     let instance = ty::Instance {