Rename ImplSymblicWitness to LookupImplWitness (#5201)

The instruction does act somewhat like a witness, saying that an impl
does exist for a lookup, but the instruction more concretely represents
an impl lookup - since that is done when it is evaluated.

toolchain/check/eval_inst.cpp

@@ -223,7 +223,7 @@ auto EvalConstantInst(Context& /*context*/, SemIRLoc /*loc*/,
 }
 
 auto EvalConstantInst(Context& context, SemIRLoc loc,
-                      SemIR::ImplSymbolicWitness inst) -> ConstantEvalResult {
+                      SemIR::LookupImplWitness inst) -> ConstantEvalResult {
   auto result = EvalLookupSingleImplWitness(
       context, UnwrapSemIRLoc()(context, loc), inst);
   if (!result.has_value()) {

toolchain/check/impl_lookup.cpp

@@ -322,7 +322,7 @@ static auto FindWitnessInFacet(
 }
 
 // Begin a search for an impl declaration matching the query. We do this by
-// creating an ImplSymbolicWitness instruction and evaluating. If it's able to
+// creating an LookupImplWitness instruction and evaluating. If it's able to
 // find a final concrete impl, then it will evaluate to that `ImplWitness` but
 // if not, it will evaluate to itself as a symbolic witness to be further
 // evaluated with a more specific query when building a specific for the generic
@@ -333,7 +333,7 @@ static auto FindWitnessInImpls(Context& context, SemIR::LocId loc_id,
     -> SemIR::InstId {
   auto witness_const_id = TryEvalInst(
       context, loc_id, SemIR::InstId::None,
-      SemIR::ImplSymbolicWitness{
+      SemIR::LookupImplWitness{
           .type_id =
               GetSingletonType(context, SemIR::WitnessType::SingletonInstId),
           .query_self_inst_id =
@@ -342,7 +342,7 @@ static auto FindWitnessInImpls(Context& context, SemIR::LocId loc_id,
               context.specific_interfaces().Add(interface),
       });
   // We use a NotConstant result from eval to communicate back an impl
-  // lookup failure. See `EvalConstantInst()` for `ImplSymbolicWitness`.
+  // lookup failure. See `EvalConstantInst()` for `LookupImplWitness`.
   if (!witness_const_id.is_constant()) {
     return SemIR::InstId::None;
   }
@@ -546,7 +546,7 @@ static auto CollectCandidateImplsForQuery(
 }
 
 auto EvalLookupSingleImplWitness(Context& context, SemIR::LocId loc_id,
-                                 SemIR::ImplSymbolicWitness eval_query)
+                                 SemIR::LookupImplWitness eval_query)
     -> EvalImplLookupResult {
   SemIR::ConstantId query_self_const_id =
       context.constant_values().Get(eval_query.query_self_inst_id);

toolchain/check/impl_lookup.h

@@ -90,11 +90,11 @@ class EvalImplLookupResult {
 
 // Looks for a witness instruction of an impl declaration for a query consisting
 // of a type value or facet value, and a single interface. This is for eval to
-// execute lookup via the ImplSymbolicWitness instruction. It does not consider
+// execute lookup via the LookupImplWitness instruction. It does not consider
 // the self facet value for finding a witness, since LookupImplWitness() would
 // have found that and not caused us to defer lookup to here.
 auto EvalLookupSingleImplWitness(Context& context, SemIR::LocId loc_id,
-                                 SemIR::ImplSymbolicWitness eval_query)
+                                 SemIR::LookupImplWitness eval_query)
     -> EvalImplLookupResult;
 
 }  // namespace Carbon::Check

toolchain/check/import_ref.cpp

@@ -2511,7 +2511,7 @@ static auto TryResolveTypedInst(ImportRefResolver& resolver,
 }
 
 static auto TryResolveTypedInst(ImportRefResolver& resolver,
-                                SemIR::ImplSymbolicWitness inst)
+                                SemIR::LookupImplWitness inst)
     -> ResolveResult {
   auto query_self_inst_id =
       GetLocalConstantInstId(resolver, inst.query_self_inst_id);
@@ -2529,7 +2529,7 @@ static auto TryResolveTypedInst(ImportRefResolver& resolver,
       resolver, import_specific_interface.specific_id, data);
   auto query_specific_interface_id =
       resolver.local_specific_interfaces().Add(specific_interface);
-  return ResolveAs<SemIR::ImplSymbolicWitness>(
+  return ResolveAs<SemIR::LookupImplWitness>(
       resolver,
       {.type_id = GetSingletonType(resolver.local_context(),
                                    SemIR::WitnessType::SingletonInstId),
@@ -2935,7 +2935,7 @@ static auto TryResolveInstCanonical(ImportRefResolver& resolver,
     case CARBON_KIND(SemIR::ImplDecl inst): {
       return TryResolveTypedInst(resolver, inst, const_id);
     }
-    case CARBON_KIND(SemIR::ImplSymbolicWitness inst): {
+    case CARBON_KIND(SemIR::LookupImplWitness inst): {
       return TryResolveTypedInst(resolver, inst);
     }
     case CARBON_KIND(SemIR::ImplWitness inst): {

toolchain/check/testdata/facet/min_prelude/convert_facet_value_to_narrowed_facet_type.carbon

@@ -743,9 +743,9 @@ fn CallsWithTypeExplicit(U:! type) {
 // CHECK:STDOUT:   %W.as_wit.iface0: <witness> = facet_access_witness %W, element0 [symbolic]
 // CHECK:STDOUT:   %Animal.facet: %Animal.type = facet_value %W.as_type, (%W.as_wit.iface0) [symbolic]
 // CHECK:STDOUT:   %impl_witness.1d8: <witness> = impl_witness (), @impl.e7b(%Animal.facet) [symbolic]
-// CHECK:STDOUT:   %Eats.impl_symbolic_witness: <witness> = impl_symbolic_witness %W, @Eats [symbolic]
+// CHECK:STDOUT:   %Eats.lookup_impl_witness: <witness> = lookup_impl_witness %W, @Eats [symbolic]
 // CHECK:STDOUT:   %W.as_wit.iface1: <witness> = facet_access_witness %W, element1 [symbolic]
-// CHECK:STDOUT:   %facet_value: %facet_type.6ff = facet_value %W.as_type, (%Eats.impl_symbolic_witness, %W.as_wit.iface1) [symbolic]
+// CHECK:STDOUT:   %facet_value: %facet_type.6ff = facet_value %W.as_type, (%Eats.lookup_impl_witness, %W.as_wit.iface1) [symbolic]
 // CHECK:STDOUT:   %FeedTame2.specific_fn: <specific function> = specific_function %FeedTame2, @FeedTame2(%facet_value) [symbolic]
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
@@ -942,8 +942,8 @@ fn CallsWithTypeExplicit(U:! type) {
 // CHECK:STDOUT:   %W.as_wit.iface0.loc12_14.3: <witness> = facet_access_witness %W.loc11_22.2, element0 [symbolic = %W.as_wit.iface0.loc12_14.3 (constants.%W.as_wit.iface0)]
 // CHECK:STDOUT:   %Animal.facet.loc12_14.3: %Animal.type = facet_value %W.as_type.loc11_44.2, (%W.as_wit.iface0.loc12_14.3) [symbolic = %Animal.facet.loc12_14.3 (constants.%Animal.facet)]
 // CHECK:STDOUT:   %W.as_wit.iface1.loc12_14.3: <witness> = facet_access_witness %W.loc11_22.2, element1 [symbolic = %W.as_wit.iface1.loc12_14.3 (constants.%W.as_wit.iface1)]
-// CHECK:STDOUT:   %Eats.impl_symbolic_witness: <witness> = impl_symbolic_witness %W.loc11_22.2, @Eats [symbolic = %Eats.impl_symbolic_witness (constants.%Eats.impl_symbolic_witness)]
-// CHECK:STDOUT:   %facet_value.loc12_14.3: %facet_type.6ff = facet_value %W.as_type.loc11_44.2, (%Eats.impl_symbolic_witness, %W.as_wit.iface1.loc12_14.3) [symbolic = %facet_value.loc12_14.3 (constants.%facet_value)]
+// CHECK:STDOUT:   %Eats.lookup_impl_witness: <witness> = lookup_impl_witness %W.loc11_22.2, @Eats [symbolic = %Eats.lookup_impl_witness (constants.%Eats.lookup_impl_witness)]
+// CHECK:STDOUT:   %facet_value.loc12_14.3: %facet_type.6ff = facet_value %W.as_type.loc11_44.2, (%Eats.lookup_impl_witness, %W.as_wit.iface1.loc12_14.3) [symbolic = %facet_value.loc12_14.3 (constants.%facet_value)]
 // CHECK:STDOUT:   %FeedTame2.specific_fn.loc12_3.2: <specific function> = specific_function constants.%FeedTame2, @FeedTame2(%facet_value.loc12_14.3) [symbolic = %FeedTame2.specific_fn.loc12_3.2 (constants.%FeedTame2.specific_fn)]
 // CHECK:STDOUT:
 // CHECK:STDOUT:   fn[%W.patt.loc11_22.1: %facet_type.65c](%w.param_patt: @HandleTameAnimal2.%W.as_type.loc11_44.2 (%W.as_type)) {
@@ -956,7 +956,7 @@ fn CallsWithTypeExplicit(U:! type) {
 // CHECK:STDOUT:     %Animal.facet.loc12_14.1: %Animal.type = facet_value constants.%W.as_type, (%W.as_wit.iface0.loc12_14.1) [symbolic = %Animal.facet.loc12_14.3 (constants.%Animal.facet)]
 // CHECK:STDOUT:     %.loc12_14.2: %Animal.type = converted %.loc12_14.1, %Animal.facet.loc12_14.1 [symbolic = %Animal.facet.loc12_14.3 (constants.%Animal.facet)]
 // CHECK:STDOUT:     %W.as_wit.iface1.loc12_14.1: <witness> = facet_access_witness constants.%W, element1 [symbolic = %W.as_wit.iface1.loc12_14.3 (constants.%W.as_wit.iface1)]
-// CHECK:STDOUT:     %facet_value.loc12_14.1: %facet_type.6ff = facet_value constants.%W.as_type, (constants.%Eats.impl_symbolic_witness, %W.as_wit.iface1.loc12_14.1) [symbolic = %facet_value.loc12_14.3 (constants.%facet_value)]
+// CHECK:STDOUT:     %facet_value.loc12_14.1: %facet_type.6ff = facet_value constants.%W.as_type, (constants.%Eats.lookup_impl_witness, %W.as_wit.iface1.loc12_14.1) [symbolic = %facet_value.loc12_14.3 (constants.%facet_value)]
 // CHECK:STDOUT:     %.loc12_14.3: %facet_type.6ff = converted constants.%W.as_type, %facet_value.loc12_14.1 [symbolic = %facet_value.loc12_14.3 (constants.%facet_value)]
 // CHECK:STDOUT:     %W.as_type.loc12_14.2: type = facet_access_type constants.%W [symbolic = %W.as_type.loc11_44.2 (constants.%W.as_type)]
 // CHECK:STDOUT:     %.loc12_14.4: type = converted constants.%W, %W.as_type.loc12_14.2 [symbolic = %W.as_type.loc11_44.2 (constants.%W.as_type)]
@@ -964,7 +964,7 @@ fn CallsWithTypeExplicit(U:! type) {
 // CHECK:STDOUT:     %Animal.facet.loc12_14.2: %Animal.type = facet_value constants.%W.as_type, (%W.as_wit.iface0.loc12_14.2) [symbolic = %Animal.facet.loc12_14.3 (constants.%Animal.facet)]
 // CHECK:STDOUT:     %.loc12_14.5: %Animal.type = converted %.loc12_14.4, %Animal.facet.loc12_14.2 [symbolic = %Animal.facet.loc12_14.3 (constants.%Animal.facet)]
 // CHECK:STDOUT:     %W.as_wit.iface1.loc12_14.2: <witness> = facet_access_witness constants.%W, element1 [symbolic = %W.as_wit.iface1.loc12_14.3 (constants.%W.as_wit.iface1)]
-// CHECK:STDOUT:     %facet_value.loc12_14.2: %facet_type.6ff = facet_value constants.%W.as_type, (constants.%Eats.impl_symbolic_witness, %W.as_wit.iface1.loc12_14.2) [symbolic = %facet_value.loc12_14.3 (constants.%facet_value)]
+// CHECK:STDOUT:     %facet_value.loc12_14.2: %facet_type.6ff = facet_value constants.%W.as_type, (constants.%Eats.lookup_impl_witness, %W.as_wit.iface1.loc12_14.2) [symbolic = %facet_value.loc12_14.3 (constants.%facet_value)]
 // CHECK:STDOUT:     %.loc12_14.6: %facet_type.6ff = converted constants.%W.as_type, %facet_value.loc12_14.2 [symbolic = %facet_value.loc12_14.3 (constants.%facet_value)]
 // CHECK:STDOUT:     %FeedTame2.specific_fn.loc12_3.1: <specific function> = specific_function %FeedTame2.ref, @FeedTame2(constants.%facet_value) [symbolic = %FeedTame2.specific_fn.loc12_3.2 (constants.%FeedTame2.specific_fn)]
 // CHECK:STDOUT:     %FeedTame2.call: init %empty_tuple.type = call %FeedTame2.specific_fn.loc12_3.1(%w.ref)

toolchain/check/testdata/facet/min_prelude/convert_facet_value_value_to_blanket_impl.carbon

@@ -45,8 +45,8 @@ fn HandleAnimal[T:! Animal](a: T) { Feed(a); }
 // CHECK:STDOUT:   %HandleAnimal: %HandleAnimal.type = struct_value () [concrete]
 // CHECK:STDOUT:   %require_complete.234: <witness> = require_complete_type %T.as_type.2ad [symbolic]
 // CHECK:STDOUT:   %impl_witness.11010a.2: <witness> = impl_witness (), @impl(%T.fd4) [symbolic]
-// CHECK:STDOUT:   %Eats.impl_symbolic_witness: <witness> = impl_symbolic_witness %T.fd4, @Eats [symbolic]
-// CHECK:STDOUT:   %Eats.facet: %Eats.type = facet_value %T.as_type.2ad, (%Eats.impl_symbolic_witness) [symbolic]
+// CHECK:STDOUT:   %Eats.lookup_impl_witness: <witness> = lookup_impl_witness %T.fd4, @Eats [symbolic]
+// CHECK:STDOUT:   %Eats.facet: %Eats.type = facet_value %T.as_type.2ad, (%Eats.lookup_impl_witness) [symbolic]
 // CHECK:STDOUT:   %Feed.specific_fn: <specific function> = specific_function %Feed, @Feed(%Eats.facet) [symbolic]
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
@@ -161,8 +161,8 @@ fn HandleAnimal[T:! Animal](a: T) { Feed(a); }
 // CHECK:STDOUT:
 // CHECK:STDOUT: !definition:
 // CHECK:STDOUT:   %require_complete: <witness> = require_complete_type @HandleAnimal.%T.as_type.loc21_32.2 (%T.as_type.2ad) [symbolic = %require_complete (constants.%require_complete.234)]
-// CHECK:STDOUT:   %Eats.impl_symbolic_witness: <witness> = impl_symbolic_witness %T.loc21_17.2, @Eats [symbolic = %Eats.impl_symbolic_witness (constants.%Eats.impl_symbolic_witness)]
-// CHECK:STDOUT:   %Eats.facet.loc21_43.3: %Eats.type = facet_value %T.as_type.loc21_32.2, (%Eats.impl_symbolic_witness) [symbolic = %Eats.facet.loc21_43.3 (constants.%Eats.facet)]
+// CHECK:STDOUT:   %Eats.lookup_impl_witness: <witness> = lookup_impl_witness %T.loc21_17.2, @Eats [symbolic = %Eats.lookup_impl_witness (constants.%Eats.lookup_impl_witness)]
+// CHECK:STDOUT:   %Eats.facet.loc21_43.3: %Eats.type = facet_value %T.as_type.loc21_32.2, (%Eats.lookup_impl_witness) [symbolic = %Eats.facet.loc21_43.3 (constants.%Eats.facet)]
 // CHECK:STDOUT:   %Feed.specific_fn.loc21_37.2: <specific function> = specific_function constants.%Feed, @Feed(%Eats.facet.loc21_43.3) [symbolic = %Feed.specific_fn.loc21_37.2 (constants.%Feed.specific_fn)]
 // CHECK:STDOUT:
 // CHECK:STDOUT:   fn[%T.patt.loc21_17.1: %Animal.type](%a.param_patt: @HandleAnimal.%T.as_type.loc21_32.2 (%T.as_type.2ad)) {
@@ -172,12 +172,12 @@ fn HandleAnimal[T:! Animal](a: T) { Feed(a); }
 // CHECK:STDOUT:     %T.as_type.loc21_43.1: type = facet_access_type constants.%T.fd4 [symbolic = %T.as_type.loc21_32.2 (constants.%T.as_type.2ad)]
 // CHECK:STDOUT:     %.loc21_43.1: type = converted constants.%T.fd4, %T.as_type.loc21_43.1 [symbolic = %T.as_type.loc21_32.2 (constants.%T.as_type.2ad)]
 // CHECK:STDOUT:     %.loc21_43.2: %Animal.type = converted %.loc21_43.1, constants.%T.fd4 [symbolic = %T.loc21_17.2 (constants.%T.fd4)]
-// CHECK:STDOUT:     %Eats.facet.loc21_43.1: %Eats.type = facet_value constants.%T.as_type.2ad, (constants.%Eats.impl_symbolic_witness) [symbolic = %Eats.facet.loc21_43.3 (constants.%Eats.facet)]
+// CHECK:STDOUT:     %Eats.facet.loc21_43.1: %Eats.type = facet_value constants.%T.as_type.2ad, (constants.%Eats.lookup_impl_witness) [symbolic = %Eats.facet.loc21_43.3 (constants.%Eats.facet)]
 // CHECK:STDOUT:     %.loc21_43.3: %Eats.type = converted constants.%T.as_type.2ad, %Eats.facet.loc21_43.1 [symbolic = %Eats.facet.loc21_43.3 (constants.%Eats.facet)]
 // CHECK:STDOUT:     %T.as_type.loc21_43.2: type = facet_access_type constants.%T.fd4 [symbolic = %T.as_type.loc21_32.2 (constants.%T.as_type.2ad)]
 // CHECK:STDOUT:     %.loc21_43.4: type = converted constants.%T.fd4, %T.as_type.loc21_43.2 [symbolic = %T.as_type.loc21_32.2 (constants.%T.as_type.2ad)]
 // CHECK:STDOUT:     %.loc21_43.5: %Animal.type = converted %.loc21_43.4, constants.%T.fd4 [symbolic = %T.loc21_17.2 (constants.%T.fd4)]
-// CHECK:STDOUT:     %Eats.facet.loc21_43.2: %Eats.type = facet_value constants.%T.as_type.2ad, (constants.%Eats.impl_symbolic_witness) [symbolic = %Eats.facet.loc21_43.3 (constants.%Eats.facet)]
+// CHECK:STDOUT:     %Eats.facet.loc21_43.2: %Eats.type = facet_value constants.%T.as_type.2ad, (constants.%Eats.lookup_impl_witness) [symbolic = %Eats.facet.loc21_43.3 (constants.%Eats.facet)]
 // CHECK:STDOUT:     %.loc21_43.6: %Eats.type = converted constants.%T.as_type.2ad, %Eats.facet.loc21_43.2 [symbolic = %Eats.facet.loc21_43.3 (constants.%Eats.facet)]
 // CHECK:STDOUT:     %Feed.specific_fn.loc21_37.1: <specific function> = specific_function %Feed.ref, @Feed(constants.%Eats.facet) [symbolic = %Feed.specific_fn.loc21_37.2 (constants.%Feed.specific_fn)]
 // CHECK:STDOUT:     %Feed.call: init %empty_tuple.type = call %Feed.specific_fn.loc21_37.1(%a.ref)

toolchain/check/testdata/facet/min_prelude/convert_facet_value_value_to_generic_facet_value_value.carbon

@@ -84,9 +84,9 @@ fn F() {
 // CHECK:STDOUT:   %Eats.type.f54c3d.2: type = facet_type <@Eats, @Eats(%Food.as_type.fae)> [symbolic]
 // CHECK:STDOUT:   %require_complete.42532a.2: <witness> = require_complete_type %Eats.type.f54c3d.2 [symbolic]
 // CHECK:STDOUT:   %impl_witness.c7c36b.2: <witness> = impl_witness (), @impl.009(%T.fd4, %Food.5fe) [symbolic]
-// CHECK:STDOUT:   %Eats.impl_symbolic_witness: <witness> = impl_symbolic_witness %T.fd4, @Eats, @Eats(%Food.as_type.fae) [symbolic]
-// CHECK:STDOUT:   %Eats.facet.eea: %Eats.type.f54c3d.2 = facet_value %T.as_type.2ad, (%Eats.impl_symbolic_witness) [symbolic]
-// CHECK:STDOUT:   %Feed.specific_fn.824: <specific function> = specific_function %Feed, @Feed(%Food.5fe, %Eats.facet.eea) [symbolic]
+// CHECK:STDOUT:   %Eats.lookup_impl_witness: <witness> = lookup_impl_witness %T.fd4, @Eats, @Eats(%Food.as_type.fae) [symbolic]
+// CHECK:STDOUT:   %Eats.facet.512: %Eats.type.f54c3d.2 = facet_value %T.as_type.2ad, (%Eats.lookup_impl_witness) [symbolic]
+// CHECK:STDOUT:   %Feed.specific_fn.ea3: <specific function> = specific_function %Feed, @Feed(%Food.5fe, %Eats.facet.512) [symbolic]
 // CHECK:STDOUT:   %F.type: type = fn_type @F [concrete]
 // CHECK:STDOUT:   %F: %F.type = struct_value () [concrete]
 // CHECK:STDOUT:   %Goat.val: %Goat = struct_value () [concrete]
@@ -334,9 +334,9 @@ fn F() {
 // CHECK:STDOUT:   %require_complete.loc31_45: <witness> = require_complete_type @HandleAnimal.%T.as_type.loc31_47.2 (%T.as_type.2ad) [symbolic = %require_complete.loc31_45 (constants.%require_complete.234)]
 // CHECK:STDOUT:   %require_complete.loc31_54: <witness> = require_complete_type @HandleAnimal.%Food.as_type.loc31_56.2 (%Food.as_type.fae) [symbolic = %require_complete.loc31_54 (constants.%require_complete.444)]
 // CHECK:STDOUT:   %Eats.type: type = facet_type <@Eats, @Eats(%Food.as_type.loc31_56.2)> [symbolic = %Eats.type (constants.%Eats.type.f54c3d.2)]
-// CHECK:STDOUT:   %Eats.impl_symbolic_witness: <witness> = impl_symbolic_witness %T.loc31_17.2, @Eats, @Eats(%Food.as_type.loc31_56.2) [symbolic = %Eats.impl_symbolic_witness (constants.%Eats.impl_symbolic_witness)]
-// CHECK:STDOUT:   %Eats.facet.loc31_76.2: @HandleAnimal.%Eats.type (%Eats.type.f54c3d.2) = facet_value %T.as_type.loc31_47.2, (%Eats.impl_symbolic_witness) [symbolic = %Eats.facet.loc31_76.2 (constants.%Eats.facet.eea)]
-// CHECK:STDOUT:   %Feed.specific_fn.loc31_64.2: <specific function> = specific_function constants.%Feed, @Feed(%Food.loc31_29.2, %Eats.facet.loc31_76.2) [symbolic = %Feed.specific_fn.loc31_64.2 (constants.%Feed.specific_fn.824)]
+// CHECK:STDOUT:   %Eats.lookup_impl_witness: <witness> = lookup_impl_witness %T.loc31_17.2, @Eats, @Eats(%Food.as_type.loc31_56.2) [symbolic = %Eats.lookup_impl_witness (constants.%Eats.lookup_impl_witness)]
+// CHECK:STDOUT:   %Eats.facet.loc31_76.2: @HandleAnimal.%Eats.type (%Eats.type.f54c3d.2) = facet_value %T.as_type.loc31_47.2, (%Eats.lookup_impl_witness) [symbolic = %Eats.facet.loc31_76.2 (constants.%Eats.facet.512)]
+// CHECK:STDOUT:   %Feed.specific_fn.loc31_64.2: <specific function> = specific_function constants.%Feed, @Feed(%Food.loc31_29.2, %Eats.facet.loc31_76.2) [symbolic = %Feed.specific_fn.loc31_64.2 (constants.%Feed.specific_fn.ea3)]
 // CHECK:STDOUT:
 // CHECK:STDOUT:   fn[%T.patt.loc31_17.1: %Animal.type, %Food.patt.loc31_29.1: %Edible.type](%a.param_patt: @HandleAnimal.%T.as_type.loc31_47.2 (%T.as_type.2ad), %food.param_patt: @HandleAnimal.%Food.as_type.loc31_56.2 (%Food.as_type.fae)) {
 // CHECK:STDOUT:   !entry:
@@ -349,9 +349,9 @@ fn F() {
 // CHECK:STDOUT:     %T.as_type.loc31_76: type = facet_access_type constants.%T.fd4 [symbolic = %T.as_type.loc31_47.2 (constants.%T.as_type.2ad)]
 // CHECK:STDOUT:     %.loc31_76.4: type = converted constants.%T.fd4, %T.as_type.loc31_76 [symbolic = %T.as_type.loc31_47.2 (constants.%T.as_type.2ad)]
 // CHECK:STDOUT:     %.loc31_76.5: %Animal.type = converted %.loc31_76.4, constants.%T.fd4 [symbolic = %T.loc31_17.2 (constants.%T.fd4)]
-// CHECK:STDOUT:     %Eats.facet.loc31_76.1: @HandleAnimal.%Eats.type (%Eats.type.f54c3d.2) = facet_value constants.%T.as_type.2ad, (constants.%Eats.impl_symbolic_witness) [symbolic = %Eats.facet.loc31_76.2 (constants.%Eats.facet.eea)]
-// CHECK:STDOUT:     %.loc31_76.6: @HandleAnimal.%Eats.type (%Eats.type.f54c3d.2) = converted constants.%T.as_type.2ad, %Eats.facet.loc31_76.1 [symbolic = %Eats.facet.loc31_76.2 (constants.%Eats.facet.eea)]
-// CHECK:STDOUT:     %Feed.specific_fn.loc31_64.1: <specific function> = specific_function %Feed.ref, @Feed(constants.%Food.5fe, constants.%Eats.facet.eea) [symbolic = %Feed.specific_fn.loc31_64.2 (constants.%Feed.specific_fn.824)]
+// CHECK:STDOUT:     %Eats.facet.loc31_76.1: @HandleAnimal.%Eats.type (%Eats.type.f54c3d.2) = facet_value constants.%T.as_type.2ad, (constants.%Eats.lookup_impl_witness) [symbolic = %Eats.facet.loc31_76.2 (constants.%Eats.facet.512)]
+// CHECK:STDOUT:     %.loc31_76.6: @HandleAnimal.%Eats.type (%Eats.type.f54c3d.2) = converted constants.%T.as_type.2ad, %Eats.facet.loc31_76.1 [symbolic = %Eats.facet.loc31_76.2 (constants.%Eats.facet.512)]
+// CHECK:STDOUT:     %Feed.specific_fn.loc31_64.1: <specific function> = specific_function %Feed.ref, @Feed(constants.%Food.5fe, constants.%Eats.facet.512) [symbolic = %Feed.specific_fn.loc31_64.2 (constants.%Feed.specific_fn.ea3)]
 // CHECK:STDOUT:     %Feed.call: init %empty_tuple.type = call %Feed.specific_fn.loc31_64.1(%a.ref, %food.ref)
 // CHECK:STDOUT:     return
 // CHECK:STDOUT:   }
@@ -464,13 +464,13 @@ fn F() {
 // CHECK:STDOUT: !definition:
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
-// CHECK:STDOUT: specific @Feed(constants.%Food.5fe, constants.%Eats.facet.eea) {
+// CHECK:STDOUT: specific @Feed(constants.%Food.5fe, constants.%Eats.facet.512) {
 // CHECK:STDOUT:   %Food.loc30_9.2 => constants.%Food.5fe
 // CHECK:STDOUT:   %Food.patt.loc30_9.2 => constants.%Food.5fe
 // CHECK:STDOUT:   %Food.as_type.loc30_37.2 => constants.%Food.as_type.fae
 // CHECK:STDOUT:   %Eats.type.loc30_37.2 => constants.%Eats.type.f54c3d.2
-// CHECK:STDOUT:   %T.loc30_24.2 => constants.%Eats.facet.eea
-// CHECK:STDOUT:   %T.patt.loc30_24.2 => constants.%Eats.facet.eea
+// CHECK:STDOUT:   %T.loc30_24.2 => constants.%Eats.facet.512
+// CHECK:STDOUT:   %T.patt.loc30_24.2 => constants.%Eats.facet.512
 // CHECK:STDOUT:   %T.as_type.loc30_43.2 => constants.%T.as_type.2ad
 // CHECK:STDOUT:
 // CHECK:STDOUT: !definition:
@@ -494,7 +494,7 @@ fn F() {
 // CHECK:STDOUT:   %require_complete.loc31_45 => constants.%complete_type.357
 // CHECK:STDOUT:   %require_complete.loc31_54 => constants.%complete_type.357
 // CHECK:STDOUT:   %Eats.type => constants.%Eats.type.1ae
-// CHECK:STDOUT:   %Eats.impl_symbolic_witness => constants.%impl_witness.4f1
+// CHECK:STDOUT:   %Eats.lookup_impl_witness => constants.%impl_witness.4f1
 // CHECK:STDOUT:   %Eats.facet.loc31_76.2 => constants.%Eats.facet.fa6
 // CHECK:STDOUT:   %Feed.specific_fn.loc31_64.2 => constants.%Feed.specific_fn.d82
 // CHECK:STDOUT: }

toolchain/check/testdata/function/generic/deduce.carbon

@@ -1519,18 +1519,18 @@ fn F() {
 // CHECK:STDOUT:   %CC.type: type = generic_class_type @CC [concrete]
 // CHECK:STDOUT:   %CC.generic: %CC.type = struct_value () [concrete]
 // CHECK:STDOUT:   %CC.a2f: type = class_type @CC, @CC(%D) [symbolic]
-// CHECK:STDOUT:   %Z.impl_symbolic_witness: <witness> = impl_symbolic_witness %DD.296, @Z [symbolic]
-// CHECK:STDOUT:   %Z.facet.f61: %Z.type = facet_value %DD.296, (%Z.impl_symbolic_witness) [symbolic]
-// CHECK:STDOUT:   %CC.43f: type = class_type @CC, @CC(%Z.facet.f61) [symbolic]
-// CHECK:STDOUT:   %impl_witness.dd1: <witness> = impl_witness (), @impl.5bc(%E) [symbolic]
+// CHECK:STDOUT:   %Z.lookup_impl_witness: <witness> = lookup_impl_witness %DD.296, @Z [symbolic]
+// CHECK:STDOUT:   %Z.facet.aae: %Z.type = facet_value %DD.296, (%Z.lookup_impl_witness) [symbolic]
+// CHECK:STDOUT:   %CC.23e: type = class_type @CC, @CC(%Z.facet.aae) [symbolic]
+// CHECK:STDOUT:   %impl_witness.1a4: <witness> = impl_witness (), @impl.497(%E) [symbolic]
 // CHECK:STDOUT:   %F.type: type = fn_type @F [concrete]
 // CHECK:STDOUT:   %F: %F.type = struct_value () [concrete]
 // CHECK:STDOUT:   %DD.689: type = class_type @DD, @DD(%EE) [concrete]
 // CHECK:STDOUT:   %impl_witness.f62: <witness> = impl_witness (), @impl.266(%EE) [concrete]
 // CHECK:STDOUT:   %Z.facet.85b: %Z.type = facet_value %DD.689, (%impl_witness.f62) [concrete]
 // CHECK:STDOUT:   %CC.4de: type = class_type @CC, @CC(%Z.facet.85b) [concrete]
-// CHECK:STDOUT:   %impl_witness.6b1: <witness> = impl_witness (), @impl.5bc(%EE) [concrete]
-// CHECK:STDOUT:   %Z.facet.a6a: %Z.type = facet_value %CC.4de, (%impl_witness.6b1) [concrete]
+// CHECK:STDOUT:   %impl_witness.ebe: <witness> = impl_witness (), @impl.497(%EE) [concrete]
+// CHECK:STDOUT:   %Z.facet.833: %Z.type = facet_value %CC.4de, (%impl_witness.ebe) [concrete]
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
@@ -1578,20 +1578,20 @@ fn F() {
 // CHECK:STDOUT:     %Z.ref: type = name_ref Z, file.%Z.decl [concrete = constants.%Z.type]
 // CHECK:STDOUT:     %D.loc11_10.1: %Z.type = bind_symbolic_name D, 0 [symbolic = %D.loc11_10.2 (constants.%D)]
 // CHECK:STDOUT:   }
-// CHECK:STDOUT:   impl_decl @impl.5bc [concrete] {
+// CHECK:STDOUT:   impl_decl @impl.497 [concrete] {
 // CHECK:STDOUT:     %E.patt.loc12_14.1: type = symbolic_binding_pattern E, 0 [symbolic = %E.patt.loc12_14.2 (constants.%E.patt)]
 // CHECK:STDOUT:   } {
 // CHECK:STDOUT:     %CC.ref: %CC.type = name_ref CC, file.%CC.decl [concrete = constants.%CC.generic]
 // CHECK:STDOUT:     %DD.ref: %DD.type = name_ref DD, file.%DD.decl [concrete = constants.%DD.generic]
 // CHECK:STDOUT:     %E.ref: type = name_ref E, %E.loc12_14.1 [symbolic = %E.loc12_14.2 (constants.%E)]
 // CHECK:STDOUT:     %DD.loc12_31.1: type = class_type @DD, @DD(constants.%E) [symbolic = %DD.loc12_31.2 (constants.%DD.296)]
-// CHECK:STDOUT:     %Z.facet.loc12_32.1: %Z.type = facet_value constants.%DD.296, (constants.%Z.impl_symbolic_witness) [symbolic = %Z.facet.loc12_32.2 (constants.%Z.facet.f61)]
-// CHECK:STDOUT:     %.loc12: %Z.type = converted %DD.loc12_31.1, %Z.facet.loc12_32.1 [symbolic = %Z.facet.loc12_32.2 (constants.%Z.facet.f61)]
-// CHECK:STDOUT:     %CC.loc12_32.1: type = class_type @CC, @CC(constants.%Z.facet.f61) [symbolic = %CC.loc12_32.2 (constants.%CC.43f)]
+// CHECK:STDOUT:     %Z.facet.loc12_32.1: %Z.type = facet_value constants.%DD.296, (constants.%Z.lookup_impl_witness) [symbolic = %Z.facet.loc12_32.2 (constants.%Z.facet.aae)]
+// CHECK:STDOUT:     %.loc12: %Z.type = converted %DD.loc12_31.1, %Z.facet.loc12_32.1 [symbolic = %Z.facet.loc12_32.2 (constants.%Z.facet.aae)]
+// CHECK:STDOUT:     %CC.loc12_32.1: type = class_type @CC, @CC(constants.%Z.facet.aae) [symbolic = %CC.loc12_32.2 (constants.%CC.23e)]
 // CHECK:STDOUT:     %Z.ref: type = name_ref Z, file.%Z.decl [concrete = constants.%Z.type]
 // CHECK:STDOUT:     %E.loc12_14.1: type = bind_symbolic_name E, 0 [symbolic = %E.loc12_14.2 (constants.%E)]
 // CHECK:STDOUT:   }
-// CHECK:STDOUT:   %impl_witness.loc12: <witness> = impl_witness (), @impl.5bc(constants.%E) [symbolic = @impl.5bc.%impl_witness (constants.%impl_witness.dd1)]
+// CHECK:STDOUT:   %impl_witness.loc12: <witness> = impl_witness (), @impl.497(constants.%E) [symbolic = @impl.497.%impl_witness (constants.%impl_witness.1a4)]
 // CHECK:STDOUT:   %F.decl: %F.type = fn_decl @F [concrete = constants.%F] {} {}
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
@@ -1622,14 +1622,14 @@ fn F() {
 // CHECK:STDOUT:   }
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
-// CHECK:STDOUT: generic impl @impl.5bc(%E.loc12_14.1: type) {
+// CHECK:STDOUT: generic impl @impl.497(%E.loc12_14.1: type) {
 // CHECK:STDOUT:   %E.loc12_14.2: type = bind_symbolic_name E, 0 [symbolic = %E.loc12_14.2 (constants.%E)]
 // CHECK:STDOUT:   %E.patt.loc12_14.2: type = symbolic_binding_pattern E, 0 [symbolic = %E.patt.loc12_14.2 (constants.%E.patt)]
 // CHECK:STDOUT:   %DD.loc12_31.2: type = class_type @DD, @DD(%E.loc12_14.2) [symbolic = %DD.loc12_31.2 (constants.%DD.296)]
-// CHECK:STDOUT:   %Z.impl_symbolic_witness: <witness> = impl_symbolic_witness %DD.loc12_31.2, @Z [symbolic = %Z.impl_symbolic_witness (constants.%Z.impl_symbolic_witness)]
-// CHECK:STDOUT:   %Z.facet.loc12_32.2: %Z.type = facet_value %DD.loc12_31.2, (%Z.impl_symbolic_witness) [symbolic = %Z.facet.loc12_32.2 (constants.%Z.facet.f61)]
-// CHECK:STDOUT:   %CC.loc12_32.2: type = class_type @CC, @CC(%Z.facet.loc12_32.2) [symbolic = %CC.loc12_32.2 (constants.%CC.43f)]
-// CHECK:STDOUT:   %impl_witness: <witness> = impl_witness (), @impl.5bc(%E.loc12_14.2) [symbolic = %impl_witness (constants.%impl_witness.dd1)]
+// CHECK:STDOUT:   %Z.lookup_impl_witness: <witness> = lookup_impl_witness %DD.loc12_31.2, @Z [symbolic = %Z.lookup_impl_witness (constants.%Z.lookup_impl_witness)]
+// CHECK:STDOUT:   %Z.facet.loc12_32.2: %Z.type = facet_value %DD.loc12_31.2, (%Z.lookup_impl_witness) [symbolic = %Z.facet.loc12_32.2 (constants.%Z.facet.aae)]
+// CHECK:STDOUT:   %CC.loc12_32.2: type = class_type @CC, @CC(%Z.facet.loc12_32.2) [symbolic = %CC.loc12_32.2 (constants.%CC.23e)]
+// CHECK:STDOUT:   %impl_witness: <witness> = impl_witness (), @impl.497(%E.loc12_14.2) [symbolic = %impl_witness (constants.%impl_witness.1a4)]
 // CHECK:STDOUT:
 // CHECK:STDOUT: !definition:
 // CHECK:STDOUT:
@@ -1687,8 +1687,8 @@ fn F() {
 // CHECK:STDOUT:   %.loc15_12: %Z.type = converted %DD, %Z.facet.loc15_12 [concrete = constants.%Z.facet.85b]
 // CHECK:STDOUT:   %CC: type = class_type @CC, @CC(constants.%Z.facet.85b) [concrete = constants.%CC.4de]
 // CHECK:STDOUT:   %Z.ref: type = name_ref Z, file.%Z.decl [concrete = constants.%Z.type]
-// CHECK:STDOUT:   %Z.facet.loc15_14: %Z.type = facet_value constants.%CC.4de, (constants.%impl_witness.6b1) [concrete = constants.%Z.facet.a6a]
-// CHECK:STDOUT:   %.loc15_14: %Z.type = converted %CC, %Z.facet.loc15_14 [concrete = constants.%Z.facet.a6a]
+// CHECK:STDOUT:   %Z.facet.loc15_14: %Z.type = facet_value constants.%CC.4de, (constants.%impl_witness.ebe) [concrete = constants.%Z.facet.833]
+// CHECK:STDOUT:   %.loc15_14: %Z.type = converted %CC, %Z.facet.loc15_14 [concrete = constants.%Z.facet.833]
 // CHECK:STDOUT:   return
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
@@ -1715,26 +1715,26 @@ fn F() {
 // CHECK:STDOUT:   %D.patt.loc11_10.2 => constants.%D
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
-// CHECK:STDOUT: specific @CC(constants.%Z.facet.f61) {
-// CHECK:STDOUT:   %D.loc11_10.2 => constants.%Z.facet.f61
-// CHECK:STDOUT:   %D.patt.loc11_10.2 => constants.%Z.facet.f61
+// CHECK:STDOUT: specific @CC(constants.%Z.facet.aae) {
+// CHECK:STDOUT:   %D.loc11_10.2 => constants.%Z.facet.aae
+// CHECK:STDOUT:   %D.patt.loc11_10.2 => constants.%Z.facet.aae
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
-// CHECK:STDOUT: specific @impl.5bc(constants.%E) {
+// CHECK:STDOUT: specific @impl.497(constants.%E) {
 // CHECK:STDOUT:   %E.loc12_14.2 => constants.%E
 // CHECK:STDOUT:   %E.patt.loc12_14.2 => constants.%E
 // CHECK:STDOUT:   %DD.loc12_31.2 => constants.%DD.296
-// CHECK:STDOUT:   %Z.impl_symbolic_witness => constants.%Z.impl_symbolic_witness
-// CHECK:STDOUT:   %Z.facet.loc12_32.2 => constants.%Z.facet.f61
-// CHECK:STDOUT:   %CC.loc12_32.2 => constants.%CC.43f
-// CHECK:STDOUT:   %impl_witness => constants.%impl_witness.dd1
+// CHECK:STDOUT:   %Z.lookup_impl_witness => constants.%Z.lookup_impl_witness
+// CHECK:STDOUT:   %Z.facet.loc12_32.2 => constants.%Z.facet.aae
+// CHECK:STDOUT:   %CC.loc12_32.2 => constants.%CC.23e
+// CHECK:STDOUT:   %impl_witness => constants.%impl_witness.1a4
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
-// CHECK:STDOUT: specific @DD(@impl.5bc.%E.loc12_14.2) {}
+// CHECK:STDOUT: specific @DD(@impl.497.%E.loc12_14.2) {}
 // CHECK:STDOUT:
-// CHECK:STDOUT: specific @CC(@impl.5bc.%Z.facet.loc12_32.2) {}
+// CHECK:STDOUT: specific @CC(@impl.497.%Z.facet.loc12_32.2) {}
 // CHECK:STDOUT:
-// CHECK:STDOUT: specific @impl.5bc(%E.loc12_14.2) {}
+// CHECK:STDOUT: specific @impl.497(%E.loc12_14.2) {}
 // CHECK:STDOUT:
 // CHECK:STDOUT: specific @DD(constants.%EE) {
 // CHECK:STDOUT:   %E.loc8_10.2 => constants.%EE
@@ -1755,14 +1755,14 @@ fn F() {
 // CHECK:STDOUT:   %D.patt.loc11_10.2 => constants.%Z.facet.85b
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
-// CHECK:STDOUT: specific @impl.5bc(constants.%EE) {
+// CHECK:STDOUT: specific @impl.497(constants.%EE) {
 // CHECK:STDOUT:   %E.loc12_14.2 => constants.%EE
 // CHECK:STDOUT:   %E.patt.loc12_14.2 => constants.%EE
 // CHECK:STDOUT:   %DD.loc12_31.2 => constants.%DD.689
-// CHECK:STDOUT:   %Z.impl_symbolic_witness => constants.%impl_witness.f62
+// CHECK:STDOUT:   %Z.lookup_impl_witness => constants.%impl_witness.f62
 // CHECK:STDOUT:   %Z.facet.loc12_32.2 => constants.%Z.facet.85b
 // CHECK:STDOUT:   %CC.loc12_32.2 => constants.%CC.4de
-// CHECK:STDOUT:   %impl_witness => constants.%impl_witness.6b1
+// CHECK:STDOUT:   %impl_witness => constants.%impl_witness.ebe
 // CHECK:STDOUT:
 // CHECK:STDOUT: !definition:
 // CHECK:STDOUT: }

toolchain/check/testdata/impl/lookup/no_prelude/impl_forall.carbon

@@ -95,11 +95,11 @@ fn TestSpecific(a: A({})) -> {} {
 // CHECK:STDOUT:   %impl_witness.ab3b51.2: <witness> = impl_witness (@impl.%F.decl), @impl(%W) [symbolic]
 // CHECK:STDOUT:   %F.type.0fea45.2: type = fn_type @F.2, @impl(%W) [symbolic]
 // CHECK:STDOUT:   %F.d6ae34.2: %F.type.0fea45.2 = struct_value () [symbolic]
-// CHECK:STDOUT:   %I.impl_symbolic_witness: <witness> = impl_symbolic_witness %A.13025a.3, @I, @I(%W) [symbolic]
-// CHECK:STDOUT:   %I.facet.5fd: %I.type.325e65.3 = facet_value %A.13025a.3, (%I.impl_symbolic_witness) [symbolic]
-// CHECK:STDOUT:   %.ea0: type = fn_type_with_self_type %F.type.2aef59.3, %I.facet.5fd [symbolic]
-// CHECK:STDOUT:   %impl.elem0: %.ea0 = impl_witness_access %I.impl_symbolic_witness, element0 [symbolic]
-// CHECK:STDOUT:   %specific_impl_fn: <specific function> = specific_impl_function %impl.elem0, @F.1(%W, %I.facet.5fd) [symbolic]
+// CHECK:STDOUT:   %I.lookup_impl_witness: <witness> = lookup_impl_witness %A.13025a.3, @I, @I(%W) [symbolic]
+// CHECK:STDOUT:   %I.facet.6d2: %I.type.325e65.3 = facet_value %A.13025a.3, (%I.lookup_impl_witness) [symbolic]
+// CHECK:STDOUT:   %.fe1: type = fn_type_with_self_type %F.type.2aef59.3, %I.facet.6d2 [symbolic]
+// CHECK:STDOUT:   %impl.elem0: %.fe1 = impl_witness_access %I.lookup_impl_witness, element0 [symbolic]
+// CHECK:STDOUT:   %specific_impl_fn: <specific function> = specific_impl_function %impl.elem0, @F.1(%W, %I.facet.6d2) [symbolic]
 // CHECK:STDOUT:   %empty_struct_type: type = struct_type {} [concrete]
 // CHECK:STDOUT:   %A.235: type = class_type @A, @A(%empty_struct_type) [concrete]
 // CHECK:STDOUT:   %TestSpecific.type: type = fn_type @TestSpecific [concrete]
@@ -337,10 +337,10 @@ fn TestSpecific(a: A({})) -> {} {
 // CHECK:STDOUT:   %I.assoc_type: type = assoc_entity_type @TestGeneric.%I.type.loc18_16.2 (%I.type.325e65.3) [symbolic = %I.assoc_type (constants.%I.assoc_type.955255.3)]
 // CHECK:STDOUT:   %assoc0: @TestGeneric.%I.assoc_type (%I.assoc_type.955255.3) = assoc_entity element0, @I.%F.decl [symbolic = %assoc0 (constants.%assoc0.fef501.3)]
 // CHECK:STDOUT:   %F.type: type = fn_type @F.1, @I(%W.loc17_16.2) [symbolic = %F.type (constants.%F.type.2aef59.3)]
-// CHECK:STDOUT:   %I.impl_symbolic_witness: <witness> = impl_symbolic_witness %A.loc17_32.2, @I, @I(%W.loc17_16.2) [symbolic = %I.impl_symbolic_witness (constants.%I.impl_symbolic_witness)]
-// CHECK:STDOUT:   %I.facet: @TestGeneric.%I.type.loc18_16.2 (%I.type.325e65.3) = facet_value %A.loc17_32.2, (%I.impl_symbolic_witness) [symbolic = %I.facet (constants.%I.facet.5fd)]
-// CHECK:STDOUT:   %.loc18_11: type = fn_type_with_self_type %F.type, %I.facet [symbolic = %.loc18_11 (constants.%.ea0)]
-// CHECK:STDOUT:   %impl.elem0.loc18_11.2: @TestGeneric.%.loc18_11 (%.ea0) = impl_witness_access %I.impl_symbolic_witness, element0 [symbolic = %impl.elem0.loc18_11.2 (constants.%impl.elem0)]
+// CHECK:STDOUT:   %I.lookup_impl_witness: <witness> = lookup_impl_witness %A.loc17_32.2, @I, @I(%W.loc17_16.2) [symbolic = %I.lookup_impl_witness (constants.%I.lookup_impl_witness)]
+// CHECK:STDOUT:   %I.facet: @TestGeneric.%I.type.loc18_16.2 (%I.type.325e65.3) = facet_value %A.loc17_32.2, (%I.lookup_impl_witness) [symbolic = %I.facet (constants.%I.facet.6d2)]
+// CHECK:STDOUT:   %.loc18_11: type = fn_type_with_self_type %F.type, %I.facet [symbolic = %.loc18_11 (constants.%.fe1)]
+// CHECK:STDOUT:   %impl.elem0.loc18_11.2: @TestGeneric.%.loc18_11 (%.fe1) = impl_witness_access %I.lookup_impl_witness, element0 [symbolic = %impl.elem0.loc18_11.2 (constants.%impl.elem0)]
 // CHECK:STDOUT:   %specific_impl_fn.loc18_11.2: <specific function> = specific_impl_function %impl.elem0.loc18_11.2, @F.1(%W.loc17_16.2, %I.facet) [symbolic = %specific_impl_fn.loc18_11.2 (constants.%specific_impl_fn)]
 // CHECK:STDOUT:
 // CHECK:STDOUT:   fn[%W.patt.loc17_16.1: type](%a.param_patt: @TestGeneric.%A.loc17_32.2 (%A.13025a.3)) -> @TestGeneric.%W.loc17_16.2 (%W) {
@@ -351,9 +351,9 @@ fn TestSpecific(a: A({})) -> {} {
 // CHECK:STDOUT:     %I.type.loc18_16.1: type = facet_type <@I, @I(constants.%W)> [symbolic = %I.type.loc18_16.2 (constants.%I.type.325e65.3)]
 // CHECK:STDOUT:     %.loc18_17: @TestGeneric.%I.assoc_type (%I.assoc_type.955255.3) = specific_constant @I.%assoc0.loc8_26.1, @I(constants.%W) [symbolic = %assoc0 (constants.%assoc0.fef501.3)]
 // CHECK:STDOUT:     %F.ref: @TestGeneric.%I.assoc_type (%I.assoc_type.955255.3) = name_ref F, %.loc18_17 [symbolic = %assoc0 (constants.%assoc0.fef501.3)]
-// CHECK:STDOUT:     %impl.elem0.loc18_11.1: @TestGeneric.%.loc18_11 (%.ea0) = impl_witness_access constants.%I.impl_symbolic_witness, element0 [symbolic = %impl.elem0.loc18_11.2 (constants.%impl.elem0)]
+// CHECK:STDOUT:     %impl.elem0.loc18_11.1: @TestGeneric.%.loc18_11 (%.fe1) = impl_witness_access constants.%I.lookup_impl_witness, element0 [symbolic = %impl.elem0.loc18_11.2 (constants.%impl.elem0)]
 // CHECK:STDOUT:     %bound_method.loc18_11: <bound method> = bound_method %a.ref, %impl.elem0.loc18_11.1
-// CHECK:STDOUT:     %specific_impl_fn.loc18_11.1: <specific function> = specific_impl_function %impl.elem0.loc18_11.1, @F.1(constants.%W, constants.%I.facet.5fd) [symbolic = %specific_impl_fn.loc18_11.2 (constants.%specific_impl_fn)]
+// CHECK:STDOUT:     %specific_impl_fn.loc18_11.1: <specific function> = specific_impl_function %impl.elem0.loc18_11.1, @F.1(constants.%W, constants.%I.facet.6d2) [symbolic = %specific_impl_fn.loc18_11.2 (constants.%specific_impl_fn)]
 // CHECK:STDOUT:     %bound_method.loc18_21: <bound method> = bound_method %a.ref, %specific_impl_fn.loc18_11.1
 // CHECK:STDOUT:     %.loc18_21: init @TestGeneric.%W.loc17_16.2 (%W) = call %bound_method.loc18_21(%a.ref)
 // CHECK:STDOUT:     %.loc18_22.1: @TestGeneric.%W.loc17_16.2 (%W) = value_of_initializer %.loc18_21
@@ -510,10 +510,10 @@ fn TestSpecific(a: A({})) -> {} {
 // CHECK:STDOUT:   %F => constants.%F.d6ae34.2
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
-// CHECK:STDOUT: specific @F.1(constants.%W, constants.%I.facet.5fd) {
+// CHECK:STDOUT: specific @F.1(constants.%W, constants.%I.facet.6d2) {
 // CHECK:STDOUT:   %U => constants.%W
 // CHECK:STDOUT:   %I.type => constants.%I.type.325e65.3
-// CHECK:STDOUT:   %Self => constants.%I.facet.5fd
+// CHECK:STDOUT:   %Self => constants.%I.facet.6d2
 // CHECK:STDOUT:   %Self.as_type.loc8_14.1 => constants.%A.13025a.3
 // CHECK:STDOUT: }
 // CHECK:STDOUT:

toolchain/check/testdata/impl/no_prelude/import_builtin_call.carbon

@@ -105,11 +105,11 @@ var n: Int(64) = MakeFromClass(FromLiteral(64) as OtherInt);
 // CHECK:STDOUT:   %Add.facet.c2b: %Add.type = facet_value %MyInt, (%impl_witness) [symbolic]
 // CHECK:STDOUT:   %Double.type: type = fn_type @Double [concrete]
 // CHECK:STDOUT:   %Double: %Double.type = struct_value () [concrete]
-// CHECK:STDOUT:   %Add.impl_symbolic_witness: <witness> = impl_symbolic_witness %MyInt, @Add [symbolic]
-// CHECK:STDOUT:   %Add.facet.f76: %Add.type = facet_value %MyInt, (%Add.impl_symbolic_witness) [symbolic]
-// CHECK:STDOUT:   %.dfa: type = fn_type_with_self_type %Op.type.31b, %Add.facet.f76 [symbolic]
-// CHECK:STDOUT:   %impl.elem0: %.dfa = impl_witness_access %Add.impl_symbolic_witness, element0 [symbolic]
-// CHECK:STDOUT:   %specific_impl_fn: <specific function> = specific_impl_function %impl.elem0, @Op.1(%Add.facet.f76) [symbolic]
+// CHECK:STDOUT:   %Add.lookup_impl_witness: <witness> = lookup_impl_witness %MyInt, @Add [symbolic]
+// CHECK:STDOUT:   %Add.facet.5a7: %Add.type = facet_value %MyInt, (%Add.lookup_impl_witness) [symbolic]
+// CHECK:STDOUT:   %.0a6: type = fn_type_with_self_type %Op.type.31b, %Add.facet.5a7 [symbolic]
+// CHECK:STDOUT:   %impl.elem0: %.0a6 = impl_witness_access %Add.lookup_impl_witness, element0 [symbolic]
+// CHECK:STDOUT:   %specific_impl_fn: <specific function> = specific_impl_function %impl.elem0, @Op.1(%Add.facet.5a7) [symbolic]
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
@@ -329,10 +329,10 @@ var n: Int(64) = MakeFromClass(FromLiteral(64) as OtherInt);
 // CHECK:STDOUT:
 // CHECK:STDOUT: !definition:
 // CHECK:STDOUT:   %require_complete: <witness> = require_complete_type @Double.%MyInt.loc19_39.2 (%MyInt) [symbolic = %require_complete (constants.%require_complete.fc7)]
-// CHECK:STDOUT:   %Add.impl_symbolic_witness: <witness> = impl_symbolic_witness %MyInt.loc19_39.2, @Add [symbolic = %Add.impl_symbolic_witness (constants.%Add.impl_symbolic_witness)]
-// CHECK:STDOUT:   %Add.facet.loc20_11: %Add.type = facet_value %MyInt.loc19_39.2, (%Add.impl_symbolic_witness) [symbolic = %Add.facet.loc20_11 (constants.%Add.facet.f76)]
-// CHECK:STDOUT:   %.loc20_11: type = fn_type_with_self_type constants.%Op.type.31b, %Add.facet.loc20_11 [symbolic = %.loc20_11 (constants.%.dfa)]
-// CHECK:STDOUT:   %impl.elem0.loc20_11.2: @Double.%.loc20_11 (%.dfa) = impl_witness_access %Add.impl_symbolic_witness, element0 [symbolic = %impl.elem0.loc20_11.2 (constants.%impl.elem0)]
+// CHECK:STDOUT:   %Add.lookup_impl_witness: <witness> = lookup_impl_witness %MyInt.loc19_39.2, @Add [symbolic = %Add.lookup_impl_witness (constants.%Add.lookup_impl_witness)]
+// CHECK:STDOUT:   %Add.facet.loc20_11: %Add.type = facet_value %MyInt.loc19_39.2, (%Add.lookup_impl_witness) [symbolic = %Add.facet.loc20_11 (constants.%Add.facet.5a7)]
+// CHECK:STDOUT:   %.loc20_11: type = fn_type_with_self_type constants.%Op.type.31b, %Add.facet.loc20_11 [symbolic = %.loc20_11 (constants.%.0a6)]
+// CHECK:STDOUT:   %impl.elem0.loc20_11.2: @Double.%.loc20_11 (%.0a6) = impl_witness_access %Add.lookup_impl_witness, element0 [symbolic = %impl.elem0.loc20_11.2 (constants.%impl.elem0)]
 // CHECK:STDOUT:   %specific_impl_fn.loc20_11.2: <specific function> = specific_impl_function %impl.elem0.loc20_11.2, @Op.1(%Add.facet.loc20_11) [symbolic = %specific_impl_fn.loc20_11.2 (constants.%specific_impl_fn)]
 // CHECK:STDOUT:
 // CHECK:STDOUT:   fn[%N.patt.loc19_11.1: Core.IntLiteral](%x.param_patt: @Double.%MyInt.loc19_39.2 (%MyInt)) -> @Double.%MyInt.loc19_39.2 (%MyInt) {
@@ -340,14 +340,14 @@ var n: Int(64) = MakeFromClass(FromLiteral(64) as OtherInt);
 // CHECK:STDOUT:     %x.ref.loc20_10: @Double.%MyInt.loc19_39.2 (%MyInt) = name_ref x, %x
 // CHECK:STDOUT:     %Add.ref: type = name_ref Add, file.%Add.decl [concrete = constants.%Add.type]
 // CHECK:STDOUT:     %Op.ref: %Add.assoc_type = name_ref Op, @Add.%assoc0 [concrete = constants.%assoc0]
-// CHECK:STDOUT:     %impl.elem0.loc20_11.1: @Double.%.loc20_11 (%.dfa) = impl_witness_access constants.%Add.impl_symbolic_witness, element0 [symbolic = %impl.elem0.loc20_11.2 (constants.%impl.elem0)]
+// CHECK:STDOUT:     %impl.elem0.loc20_11.1: @Double.%.loc20_11 (%.0a6) = impl_witness_access constants.%Add.lookup_impl_witness, element0 [symbolic = %impl.elem0.loc20_11.2 (constants.%impl.elem0)]
 // CHECK:STDOUT:     %bound_method.loc20_11: <bound method> = bound_method %x.ref.loc20_10, %impl.elem0.loc20_11.1
 // CHECK:STDOUT:     %x.ref.loc20_21: @Double.%MyInt.loc19_39.2 (%MyInt) = name_ref x, %x
-// CHECK:STDOUT:     %Add.facet.loc20_22.1: %Add.type = facet_value constants.%MyInt, (constants.%Add.impl_symbolic_witness) [symbolic = %Add.facet.loc20_11 (constants.%Add.facet.f76)]
-// CHECK:STDOUT:     %.loc20_22.1: %Add.type = converted constants.%MyInt, %Add.facet.loc20_22.1 [symbolic = %Add.facet.loc20_11 (constants.%Add.facet.f76)]
-// CHECK:STDOUT:     %Add.facet.loc20_22.2: %Add.type = facet_value constants.%MyInt, (constants.%Add.impl_symbolic_witness) [symbolic = %Add.facet.loc20_11 (constants.%Add.facet.f76)]
-// CHECK:STDOUT:     %.loc20_22.2: %Add.type = converted constants.%MyInt, %Add.facet.loc20_22.2 [symbolic = %Add.facet.loc20_11 (constants.%Add.facet.f76)]
-// CHECK:STDOUT:     %specific_impl_fn.loc20_11.1: <specific function> = specific_impl_function %impl.elem0.loc20_11.1, @Op.1(constants.%Add.facet.f76) [symbolic = %specific_impl_fn.loc20_11.2 (constants.%specific_impl_fn)]
+// CHECK:STDOUT:     %Add.facet.loc20_22.1: %Add.type = facet_value constants.%MyInt, (constants.%Add.lookup_impl_witness) [symbolic = %Add.facet.loc20_11 (constants.%Add.facet.5a7)]
+// CHECK:STDOUT:     %.loc20_22.1: %Add.type = converted constants.%MyInt, %Add.facet.loc20_22.1 [symbolic = %Add.facet.loc20_11 (constants.%Add.facet.5a7)]
+// CHECK:STDOUT:     %Add.facet.loc20_22.2: %Add.type = facet_value constants.%MyInt, (constants.%Add.lookup_impl_witness) [symbolic = %Add.facet.loc20_11 (constants.%Add.facet.5a7)]
+// CHECK:STDOUT:     %.loc20_22.2: %Add.type = converted constants.%MyInt, %Add.facet.loc20_22.2 [symbolic = %Add.facet.loc20_11 (constants.%Add.facet.5a7)]
+// CHECK:STDOUT:     %specific_impl_fn.loc20_11.1: <specific function> = specific_impl_function %impl.elem0.loc20_11.1, @Op.1(constants.%Add.facet.5a7) [symbolic = %specific_impl_fn.loc20_11.2 (constants.%specific_impl_fn)]
 // CHECK:STDOUT:     %bound_method.loc20_22: <bound method> = bound_method %x.ref.loc20_10, %specific_impl_fn.loc20_11.1
 // CHECK:STDOUT:     %.loc20_22.3: init @Double.%MyInt.loc19_39.2 (%MyInt) = call %bound_method.loc20_22(%x.ref.loc20_10, %x.ref.loc20_21)
 // CHECK:STDOUT:     %.loc20_23.1: @Double.%MyInt.loc19_39.2 (%MyInt) = value_of_initializer %.loc20_22.3
@@ -407,8 +407,8 @@ var n: Int(64) = MakeFromClass(FromLiteral(64) as OtherInt);
 // CHECK:STDOUT:
 // CHECK:STDOUT: specific @MyInt(@Double.%N.loc19_11.2) {}
 // CHECK:STDOUT:
-// CHECK:STDOUT: specific @Op.1(constants.%Add.facet.f76) {
-// CHECK:STDOUT:   %Self => constants.%Add.facet.f76
+// CHECK:STDOUT: specific @Op.1(constants.%Add.facet.5a7) {
+// CHECK:STDOUT:   %Self => constants.%Add.facet.5a7
 // CHECK:STDOUT:   %Self.as_type.loc5_15.1 => constants.%MyInt
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
@@ -452,11 +452,11 @@ var n: Int(64) = MakeFromClass(FromLiteral(64) as OtherInt);
 // CHECK:STDOUT:   %CallImportedDouble: %CallImportedDouble.type = struct_value () [concrete]
 // CHECK:STDOUT:   %Double.type: type = fn_type @Double [concrete]
 // CHECK:STDOUT:   %Double: %Double.type = struct_value () [concrete]
-// CHECK:STDOUT:   %Add.impl_symbolic_witness: <witness> = impl_symbolic_witness %MyInt.09f, @Add [symbolic]
-// CHECK:STDOUT:   %Add.facet.f76: %Add.type = facet_value %MyInt.09f, (%Add.impl_symbolic_witness) [symbolic]
-// CHECK:STDOUT:   %.dfa: type = fn_type_with_self_type %Op.type.31b, %Add.facet.f76 [symbolic]
-// CHECK:STDOUT:   %impl.elem0: %.dfa = impl_witness_access %Add.impl_symbolic_witness, element0 [symbolic]
-// CHECK:STDOUT:   %specific_impl_fn: <specific function> = specific_impl_function %impl.elem0, @Op.1(%Add.facet.f76) [symbolic]
+// CHECK:STDOUT:   %Add.lookup_impl_witness: <witness> = lookup_impl_witness %MyInt.09f, @Add [symbolic]
+// CHECK:STDOUT:   %Add.facet.5a7: %Add.type = facet_value %MyInt.09f, (%Add.lookup_impl_witness) [symbolic]
+// CHECK:STDOUT:   %.0a6: type = fn_type_with_self_type %Op.type.31b, %Add.facet.5a7 [symbolic]
+// CHECK:STDOUT:   %impl.elem0: %.0a6 = impl_witness_access %Add.lookup_impl_witness, element0 [symbolic]
+// CHECK:STDOUT:   %specific_impl_fn: <specific function> = specific_impl_function %impl.elem0, @Op.1(%Add.facet.5a7) [symbolic]
 // CHECK:STDOUT:   %Double.specific_fn: <specific function> = specific_function %Double, @Double(%int_64) [concrete]
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
@@ -624,10 +624,10 @@ var n: Int(64) = MakeFromClass(FromLiteral(64) as OtherInt);
 // CHECK:STDOUT:
 // CHECK:STDOUT: !definition:
 // CHECK:STDOUT:   %require_complete: <witness> = require_complete_type @Double.%MyInt (%MyInt.09f) [symbolic = %require_complete (constants.%require_complete.fc7)]
-// CHECK:STDOUT:   %Add.impl_symbolic_witness: <witness> = impl_symbolic_witness %MyInt, @Add [symbolic = %Add.impl_symbolic_witness (constants.%Add.impl_symbolic_witness)]
-// CHECK:STDOUT:   %Add.facet: %Add.type = facet_value %MyInt, (%Add.impl_symbolic_witness) [symbolic = %Add.facet (constants.%Add.facet.f76)]
-// CHECK:STDOUT:   %.1: type = fn_type_with_self_type constants.%Op.type.31b, %Add.facet [symbolic = %.1 (constants.%.dfa)]
-// CHECK:STDOUT:   %impl.elem0: @Double.%.1 (%.dfa) = impl_witness_access %Add.impl_symbolic_witness, element0 [symbolic = %impl.elem0 (constants.%impl.elem0)]
+// CHECK:STDOUT:   %Add.lookup_impl_witness: <witness> = lookup_impl_witness %MyInt, @Add [symbolic = %Add.lookup_impl_witness (constants.%Add.lookup_impl_witness)]
+// CHECK:STDOUT:   %Add.facet: %Add.type = facet_value %MyInt, (%Add.lookup_impl_witness) [symbolic = %Add.facet (constants.%Add.facet.5a7)]
+// CHECK:STDOUT:   %.1: type = fn_type_with_self_type constants.%Op.type.31b, %Add.facet [symbolic = %.1 (constants.%.0a6)]
+// CHECK:STDOUT:   %impl.elem0: @Double.%.1 (%.0a6) = impl_witness_access %Add.lookup_impl_witness, element0 [symbolic = %impl.elem0 (constants.%impl.elem0)]
 // CHECK:STDOUT:   %specific_impl_fn: <specific function> = specific_impl_function %impl.elem0, @Op.1(%Add.facet) [symbolic = %specific_impl_fn (constants.%specific_impl_fn)]
 // CHECK:STDOUT:
 // CHECK:STDOUT:   fn[%N.patt.1: Core.IntLiteral](%x.param_patt: @Double.%MyInt (%MyInt.09f)) -> @Double.%MyInt (%MyInt.09f);
@@ -708,8 +708,8 @@ var n: Int(64) = MakeFromClass(FromLiteral(64) as OtherInt);
 // CHECK:STDOUT:   %MyInt => constants.%MyInt.09f
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
-// CHECK:STDOUT: specific @Op.1(constants.%Add.facet.f76) {
-// CHECK:STDOUT:   %Self => constants.%Add.facet.f76
+// CHECK:STDOUT: specific @Op.1(constants.%Add.facet.5a7) {
+// CHECK:STDOUT:   %Self => constants.%Add.facet.5a7
 // CHECK:STDOUT:   %Self.as_type => constants.%MyInt.09f
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
@@ -722,7 +722,7 @@ var n: Int(64) = MakeFromClass(FromLiteral(64) as OtherInt);
 // CHECK:STDOUT:
 // CHECK:STDOUT: !definition:
 // CHECK:STDOUT:   %require_complete => constants.%complete_type.4a1
-// CHECK:STDOUT:   %Add.impl_symbolic_witness => constants.%impl_witness.8d6
+// CHECK:STDOUT:   %Add.lookup_impl_witness => constants.%impl_witness.8d6
 // CHECK:STDOUT:   %Add.facet => constants.%Add.facet.8db
 // CHECK:STDOUT:   %.1 => constants.%.1ca
 // CHECK:STDOUT:   %impl.elem0 => constants.%Op.cf9

toolchain/check/testdata/interface/no_prelude/fail_assoc_const_alias.carbon

@@ -366,9 +366,9 @@ interface C {
 // CHECK:STDOUT:   %Self.541: %J2.type = bind_symbolic_name Self, 0 [symbolic]
 // CHECK:STDOUT:   %Self.as_type: type = facet_access_type %Self.541 [symbolic]
 // CHECK:STDOUT:   %impl_witness.ec95d0.2: <witness> = impl_witness (%empty_tuple.type), @impl(%Self.541) [symbolic]
-// CHECK:STDOUT:   %I2.impl_symbolic_witness: <witness> = impl_symbolic_witness %Self.541, @I2 [symbolic]
-// CHECK:STDOUT:   %I2.facet.fc4: %I2.type = facet_value %Self.as_type, (%I2.impl_symbolic_witness) [symbolic]
-// CHECK:STDOUT:   %impl.elem0.e6b: type = impl_witness_access %I2.impl_symbolic_witness, element0 [symbolic]
+// CHECK:STDOUT:   %I2.lookup_impl_witness: <witness> = lookup_impl_witness %Self.541, @I2 [symbolic]
+// CHECK:STDOUT:   %I2.facet.758: %I2.type = facet_value %Self.as_type, (%I2.lookup_impl_witness) [symbolic]
+// CHECK:STDOUT:   %impl.elem0.7c7: type = impl_witness_access %I2.lookup_impl_witness, element0 [symbolic]
 // CHECK:STDOUT:   %F2.type: type = fn_type @F2 [concrete]
 // CHECK:STDOUT:   %F2: %F2.type = struct_value () [concrete]
 // CHECK:STDOUT:   %J2.assoc_type: type = assoc_entity_type %J2.type [concrete]
@@ -434,20 +434,20 @@ interface C {
 // CHECK:STDOUT:   %T2.ref: %I2.assoc_type = name_ref T2, @T2.%assoc0 [concrete = constants.%assoc0.166]
 // CHECK:STDOUT:   %U2: %I2.assoc_type = bind_alias U2, @T2.%assoc0 [concrete = constants.%assoc0.166]
 // CHECK:STDOUT:   %F2.decl: %F2.type = fn_decl @F2 [concrete = constants.%F2] {
-// CHECK:STDOUT:     %return.patt: @F2.%impl.elem0.loc15_14.1 (%impl.elem0.e6b) = return_slot_pattern
-// CHECK:STDOUT:     %return.param_patt: @F2.%impl.elem0.loc15_14.1 (%impl.elem0.e6b) = out_param_pattern %return.patt, call_param0
+// CHECK:STDOUT:     %return.patt: @F2.%impl.elem0.loc15_14.1 (%impl.elem0.7c7) = return_slot_pattern
+// CHECK:STDOUT:     %return.param_patt: @F2.%impl.elem0.loc15_14.1 (%impl.elem0.7c7) = out_param_pattern %return.patt, call_param0
 // CHECK:STDOUT:   } {
 // CHECK:STDOUT:     %Self.as_type.loc15_14.2: type = facet_access_type constants.%Self.541 [symbolic = %Self.as_type.loc15_14.1 (constants.%Self.as_type)]
 // CHECK:STDOUT:     %.loc15_14.1: type = converted constants.%Self.541, %Self.as_type.loc15_14.2 [symbolic = %Self.as_type.loc15_14.1 (constants.%Self.as_type)]
 // CHECK:STDOUT:     %.loc15_14.2: %J2.type = converted %.loc15_14.1, constants.%Self.541 [symbolic = %Self (constants.%Self.541)]
 // CHECK:STDOUT:     %Self.as_type.loc15_14.3: type = facet_access_type constants.%Self.541 [symbolic = %Self.as_type.loc15_14.1 (constants.%Self.as_type)]
-// CHECK:STDOUT:     %I2.facet.loc15_14.2: %I2.type = facet_value %Self.as_type.loc15_14.3, (constants.%I2.impl_symbolic_witness) [symbolic = %I2.facet.loc15_14.1 (constants.%I2.facet.fc4)]
-// CHECK:STDOUT:     %.loc15_14.3: %I2.type = converted @J2.%Self, %I2.facet.loc15_14.2 [symbolic = %I2.facet.loc15_14.1 (constants.%I2.facet.fc4)]
-// CHECK:STDOUT:     %as_wit.iface0: <witness> = facet_access_witness %.loc15_14.3, element0 [symbolic = %I2.impl_symbolic_witness (constants.%I2.impl_symbolic_witness)]
-// CHECK:STDOUT:     %impl.elem0.loc15_14.2: type = impl_witness_access %as_wit.iface0, element0 [symbolic = %impl.elem0.loc15_14.1 (constants.%impl.elem0.e6b)]
-// CHECK:STDOUT:     %U2.ref: type = name_ref U2, %impl.elem0.loc15_14.2 [symbolic = %impl.elem0.loc15_14.1 (constants.%impl.elem0.e6b)]
-// CHECK:STDOUT:     %return.param: ref @F2.%impl.elem0.loc15_14.1 (%impl.elem0.e6b) = out_param call_param0
-// CHECK:STDOUT:     %return: ref @F2.%impl.elem0.loc15_14.1 (%impl.elem0.e6b) = return_slot %return.param
+// CHECK:STDOUT:     %I2.facet.loc15_14.2: %I2.type = facet_value %Self.as_type.loc15_14.3, (constants.%I2.lookup_impl_witness) [symbolic = %I2.facet.loc15_14.1 (constants.%I2.facet.758)]
+// CHECK:STDOUT:     %.loc15_14.3: %I2.type = converted @J2.%Self, %I2.facet.loc15_14.2 [symbolic = %I2.facet.loc15_14.1 (constants.%I2.facet.758)]
+// CHECK:STDOUT:     %as_wit.iface0: <witness> = facet_access_witness %.loc15_14.3, element0 [symbolic = %I2.lookup_impl_witness (constants.%I2.lookup_impl_witness)]
+// CHECK:STDOUT:     %impl.elem0.loc15_14.2: type = impl_witness_access %as_wit.iface0, element0 [symbolic = %impl.elem0.loc15_14.1 (constants.%impl.elem0.7c7)]
+// CHECK:STDOUT:     %U2.ref: type = name_ref U2, %impl.elem0.loc15_14.2 [symbolic = %impl.elem0.loc15_14.1 (constants.%impl.elem0.7c7)]
+// CHECK:STDOUT:     %return.param: ref @F2.%impl.elem0.loc15_14.1 (%impl.elem0.7c7) = out_param call_param0
+// CHECK:STDOUT:     %return: ref @F2.%impl.elem0.loc15_14.1 (%impl.elem0.7c7) = return_slot %return.param
 // CHECK:STDOUT:   }
 // CHECK:STDOUT:   %Self.as_type: type = facet_access_type constants.%Self.541 [symbolic = constants.%Self.as_type]
 // CHECK:STDOUT:   %.loc15_14.1: type = converted constants.%Self.541, %Self.as_type [symbolic = constants.%Self.as_type]
@@ -483,11 +483,11 @@ interface C {
 // CHECK:STDOUT: generic fn @F2(@J2.%Self: %J2.type) {
 // CHECK:STDOUT:   %Self: %J2.type = bind_symbolic_name Self, 0 [symbolic = %Self (constants.%Self.541)]
 // CHECK:STDOUT:   %Self.as_type.loc15_14.1: type = facet_access_type %Self [symbolic = %Self.as_type.loc15_14.1 (constants.%Self.as_type)]
-// CHECK:STDOUT:   %I2.impl_symbolic_witness: <witness> = impl_symbolic_witness %Self, @I2 [symbolic = %I2.impl_symbolic_witness (constants.%I2.impl_symbolic_witness)]
-// CHECK:STDOUT:   %I2.facet.loc15_14.1: %I2.type = facet_value %Self.as_type.loc15_14.1, (%I2.impl_symbolic_witness) [symbolic = %I2.facet.loc15_14.1 (constants.%I2.facet.fc4)]
-// CHECK:STDOUT:   %impl.elem0.loc15_14.1: type = impl_witness_access %I2.impl_symbolic_witness, element0 [symbolic = %impl.elem0.loc15_14.1 (constants.%impl.elem0.e6b)]
+// CHECK:STDOUT:   %I2.lookup_impl_witness: <witness> = lookup_impl_witness %Self, @I2 [symbolic = %I2.lookup_impl_witness (constants.%I2.lookup_impl_witness)]
+// CHECK:STDOUT:   %I2.facet.loc15_14.1: %I2.type = facet_value %Self.as_type.loc15_14.1, (%I2.lookup_impl_witness) [symbolic = %I2.facet.loc15_14.1 (constants.%I2.facet.758)]
+// CHECK:STDOUT:   %impl.elem0.loc15_14.1: type = impl_witness_access %I2.lookup_impl_witness, element0 [symbolic = %impl.elem0.loc15_14.1 (constants.%impl.elem0.7c7)]
 // CHECK:STDOUT:
-// CHECK:STDOUT:   fn() -> @F2.%impl.elem0.loc15_14.1 (%impl.elem0.e6b);
+// CHECK:STDOUT:   fn() -> @F2.%impl.elem0.loc15_14.1 (%impl.elem0.7c7);
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: specific @T2(constants.%Self.c7b) {}
@@ -512,14 +512,14 @@ interface C {
 // CHECK:STDOUT: !definition:
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
-// CHECK:STDOUT: specific @T2(constants.%I2.facet.fc4) {}
+// CHECK:STDOUT: specific @T2(constants.%I2.facet.758) {}
 // CHECK:STDOUT:
 // CHECK:STDOUT: specific @F2(constants.%Self.541) {
 // CHECK:STDOUT:   %Self => constants.%Self.541
 // CHECK:STDOUT:   %Self.as_type.loc15_14.1 => constants.%Self.as_type
-// CHECK:STDOUT:   %I2.impl_symbolic_witness => constants.%I2.impl_symbolic_witness
-// CHECK:STDOUT:   %I2.facet.loc15_14.1 => constants.%I2.facet.fc4
-// CHECK:STDOUT:   %impl.elem0.loc15_14.1 => constants.%impl.elem0.e6b
+// CHECK:STDOUT:   %I2.lookup_impl_witness => constants.%I2.lookup_impl_witness
+// CHECK:STDOUT:   %I2.facet.loc15_14.1 => constants.%I2.facet.758
+// CHECK:STDOUT:   %impl.elem0.loc15_14.1 => constants.%impl.elem0.7c7
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: --- fail_call_method_alias.carbon

toolchain/sem_ir/file.cpp

@@ -270,7 +270,7 @@ auto GetExprCategory(const File& file, InstId inst_id) -> ExprCategory {
       case FunctionTypeWithSelfType::Kind:
       case GenericClassType::Kind:
       case GenericInterfaceType::Kind:
-      case ImplSymbolicWitness::Kind:
+      case LookupImplWitness::Kind:
       case ImplWitness::Kind:
       case ImplWitnessAccess::Kind:
       case ImportCppDecl::Kind:

toolchain/sem_ir/inst_kind.def

@@ -70,7 +70,7 @@ CARBON_SEM_IR_INST_KIND(FunctionTypeWithSelfType)
 CARBON_SEM_IR_INST_KIND(GenericClassType)
 CARBON_SEM_IR_INST_KIND(GenericInterfaceType)
 CARBON_SEM_IR_INST_KIND(ImplDecl)
-CARBON_SEM_IR_INST_KIND(ImplSymbolicWitness)
+CARBON_SEM_IR_INST_KIND(LookupImplWitness)
 CARBON_SEM_IR_INST_KIND(ImplWitness)
 CARBON_SEM_IR_INST_KIND(ImplWitnessAccess)
 CARBON_SEM_IR_INST_KIND(ImportCppDecl)

toolchain/sem_ir/inst_namer.cpp

@@ -696,12 +696,12 @@ auto InstNamer::CollectNamesInBlock(ScopeId top_scope_id,
         queue_block_id(impl_scope_id, inst.decl_block_id);
         break;
       }
-      case CARBON_KIND(ImplSymbolicWitness inst): {
+      case CARBON_KIND(LookupImplWitness inst): {
         const auto& interface = sem_ir_->specific_interfaces().Get(
             inst.query_specific_interface_id);
         add_inst_name_id(
             sem_ir_->interfaces().Get(interface.interface_id).name_id,
-            ".impl_symbolic_witness");
+            ".lookup_impl_witness");
         continue;
       }
       case ImplWitness::Kind: {

toolchain/sem_ir/stringify_type.cpp

@@ -382,7 +382,7 @@ class Stringifier {
       -> void {
     auto witness_inst_id =
         sem_ir_->constant_values().GetConstantInstId(inst.witness_id);
-    if (sem_ir_->insts().Is<SemIR::ImplSymbolicWitness>(witness_inst_id)) {
+    if (sem_ir_->insts().Is<SemIR::LookupImplWitness>(witness_inst_id)) {
       // TODO: Include the query in the diagnostic output?
       step_stack_->PushString("<symbolic>");
       return;

toolchain/sem_ir/typed_insts.h

@@ -868,24 +868,6 @@ struct ImplDecl {
   DeclInstBlockId decl_block_id;
 };
 
-// A symbolic witness that a type implements an interface. It represents a
-// promise that an impl lookup query can be satisfied without providing which
-// impl declaration satisfies it. When evaluated, it does lookup again to form a
-// concrete ImplWitness from a more specific query.
-struct ImplSymbolicWitness {
-  static constexpr auto Kind =
-      InstKind::ImplSymbolicWitness.Define<Parse::NodeId>(
-          {.ir_name = "impl_symbolic_witness",
-           .constant_kind = InstConstantKind::SymbolicOnly,
-           .is_lowered = false});
-
-  // Always the type of the builtin `WitnessType` singleton instruction.
-  TypeId type_id;
-  // The self type (or facet value) and interface of the impl lookup query.
-  InstId query_self_inst_id;
-  SpecificInterfaceId query_specific_interface_id;
-};
-
 // A witness that a type implements an interface.
 struct ImplWitness {
   static constexpr auto Kind = InstKind::ImplWitness.Define<Parse::NodeId>(
@@ -1068,6 +1050,30 @@ struct IntType {
   InstId bit_width_id;
 };
 
+// A symbolic instruction that takes the place of an `ImplWitness` when the
+// result is not fully known. When evaluated it does an impl lookup query, based
+// on the stored query arguments, that a type implements an interface. The query
+// can be symbolic, and thus modified to be more concrete by applying a
+// specific. Once the query is concrete enough, or a final impl is found, the
+// instruction evaluates to an `ImplWitness`.
+//
+// This instruction also represents a promise that an impl lookup query was
+// satisfied, like `ImplWitness`, but without providing which impl declaration
+// satisfies it.
+struct LookupImplWitness {
+  static constexpr auto Kind =
+      InstKind::LookupImplWitness.Define<Parse::NodeId>(
+          {.ir_name = "lookup_impl_witness",
+           .constant_kind = InstConstantKind::SymbolicOnly,
+           .is_lowered = false});
+
+  // Always the type of the builtin `WitnessType` singleton instruction.
+  TypeId type_id;
+  // The self type (or facet value) and interface of the impl lookup query.
+  InstId query_self_inst_id;
+  SpecificInterfaceId query_specific_interface_id;
+};
+
 // A name-binding declaration, i.e. a declaration introduced with `let` or
 // `var`.
 struct NameBindingDecl {