diff --git a/explorer/README.md b/explorer/README.md
index 45a482051eae..15e2228779d1 100644
--- a/explorer/README.md
+++ b/explorer/README.md
@@ -168,24 +168,35 @@ performed during execution.
 Printing directly to the standard output using the `--trace_file` option is
 supported by passing `-` in place of a filepath (`--trace_file=-`).
 
-To customize the trace output and include specific information, you can pass the
-following list of options to `-trace_phase=...` option along with
-`--trace_file=...` option:
+Trace output can be customized by selecting program phases and file contexts for
+which tracing should be enabled. The `-trace_phase=...` option is used to select
+program phases, while the `-trace_file_context=...` option is used to select
+file contexts.
 
--   `source_program`: Include trace output for the source program phase.
--   `name_resolution`: Include trace output for the name resolution phase.
--   `control_flow_resolution`: Include trace output for the control flow
+The following options can be passed as a comma-separated list to the
+`-trace_phase=...` option to select program phases:
+
+-   `source_program`: Includes trace output for the source program phase.
+-   `name_resolution`: Includes trace output for the name resolution phase.
+-   `control_flow_resolution`: Includes trace output for the control flow
     resolution phase.
--   `type_checking`: Include trace output for the type checking phase.
--   `unformed_variables_resolution`: Include trace output for the unformed
+-   `type_checking`: Includes trace output for the type checking phase.
+-   `unformed_variables_resolution`: Includes trace output for the unformed
     variables resolution phase.
--   `declarations`: Include trace output for printing declarations.
--   `execution`: Include trace output for program execution.
--   `timing`: Include timing logs indicating the time taken by each phase.
--   `all`: Include trace output for all phases.
+-   `declarations`: Includes trace output for printing declarations.
+-   `execution`: Includes trace output for program execution.
+-   `timing`: Includes timing logs indicating the time taken by each phase.
+-   `all`: Includes trace output for all phases.
+-   By default, tracing is only enabled for the `execution` phase.
 
-By default, only execution trace will be added to the trace output. You can use
-combination of these options to include trace of multiple program phases.
+The following options can be passed as a comma-separated list to the
+`-trace_file_context=...` option to select file contexts:
+
+-   `main`: Includes trace output for the file containing the main function.
+-   `prelude`: Includes trace output for the prelude.
+-   `import`: Includes trace output for imports.
+-   `include`: Includes trace output for all.
+-   By default, tracing is only enabled for the `main` file context.
 
 ### State of the Program
 
diff --git a/explorer/common/BUILD b/explorer/common/BUILD
index a897b3bd9ff0..7bb67ba78182 100644
--- a/explorer/common/BUILD
+++ b/explorer/common/BUILD
@@ -54,6 +54,7 @@ cc_library(
     name = "trace_stream",
     hdrs = ["trace_stream.h"],
     deps = [
+        ":source_location",
         "//common:check",
         "//common:ostream",
         "//explorer/common:nonnull",
@@ -69,3 +70,14 @@ cc_test(
         "@com_google_googletest//:gtest",
     ],
 )
+
+cc_test(
+    name = "set_file_context_raii_test",
+    srcs = ["set_file_context_raii_test.cpp"],
+    deps = [
+        ":source_location",
+        ":trace_stream",
+        "//testing/util:gtest_main",
+        "@com_google_googletest//:gtest",
+    ],
+)
diff --git a/explorer/common/set_file_context_raii_test.cpp b/explorer/common/set_file_context_raii_test.cpp
new file mode 100644
index 000000000000..50c3d3d9bf6e
--- /dev/null
+++ b/explorer/common/set_file_context_raii_test.cpp
@@ -0,0 +1,47 @@
+// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
+// Exceptions. See /LICENSE for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+#include <gmock/gmock.h>
+#include <gtest/gtest.h>
+
+#include "explorer/common/trace_stream.h"
+
+namespace Carbon::Testing {
+namespace {
+
+// TODO: write test cases to distinguish between file context of main file and
+// an import once imports are supported.
+
+TEST(SetFileContextRaiiTest, Simple) {
+  TraceStream trace_stream;
+  {
+    SetFileContext set_file_ctx(trace_stream,
+                                SourceLocation("example/main.carbon", 9));
+    EXPECT_TRUE(trace_stream.file_context() == FileContext::Main);
+  }
+
+  // Considering the file context for a trace stream is FileContext::Unknown by
+  // default, as the default value of source location in a trace stream is
+  // std::nullopt.
+  EXPECT_TRUE(trace_stream.file_context() == FileContext::Unknown);
+}
+
+TEST(SetFileContextRaiiTest, UpdateFileContext) {
+  TraceStream trace_stream;
+  {
+    SetFileContext set_file_ctx(trace_stream,
+                                SourceLocation("example/prelude.carbon", 9));
+    EXPECT_TRUE(trace_stream.file_context() == FileContext::Prelude);
+    set_file_ctx.update_source_loc(SourceLocation("example/main.carbon", 9));
+    EXPECT_TRUE(trace_stream.file_context() == FileContext::Main);
+  }
+
+  // Considering the file context for a trace stream is FileContext::Unknown by
+  // default, as the default value of source location in a trace stream is
+  // std::nullopt.
+  EXPECT_TRUE(trace_stream.file_context() == FileContext::Unknown);
+}
+
+}  // namespace
+}  // namespace Carbon::Testing
diff --git a/explorer/common/source_location.h b/explorer/common/source_location.h
index 4567eddfa945..cc60434476a0 100644
--- a/explorer/common/source_location.h
+++ b/explorer/common/source_location.h
@@ -37,6 +37,8 @@ class SourceLocation {
     return filename_ == other.filename_ && line_num_ == other.line_num_;
   }
 
+  auto filename() const -> std::string_view { return filename_; }
+
   void Print(llvm::raw_ostream& out) const {
     out << filename_ << ":" << line_num_;
   }
diff --git a/explorer/common/trace_stream.h b/explorer/common/trace_stream.h
index a6d4eecec0e2..14e859081e5f 100644
--- a/explorer/common/trace_stream.h
+++ b/explorer/common/trace_stream.h
@@ -13,6 +13,7 @@
 #include "common/check.h"
 #include "common/ostream.h"
 #include "explorer/common/nonnull.h"
+#include "explorer/common/source_location.h"
 
 namespace Carbon {
 
@@ -34,6 +35,10 @@ enum class ProgramPhase {
   Last = All                   // Last program phase indicator.
 };
 
+// Enumerates the contexts for different types of files, used for tracing and
+// controlling for which file contexts tracing should be enabled.
+enum class FileContext { Unknown, Main, Prelude, Import, All, Last = All };
+
 // Encapsulates the trace stream so that we can cleanly disable tracing while
 // the prelude is being processed. The prelude is expected to take a
 // disproprotionate amount of time to log, so we try to avoid it.
@@ -45,12 +50,32 @@ enum class ProgramPhase {
 // contexts.
 class TraceStream {
  public:
+  explicit TraceStream() { set_allowed_file_contexts({FileContext::Unknown}); }
+
+  // This method gets the file context by using filename from source location.
+  // TODO: implement a way to differentiate between the main file and imports
+  // based upon source location / filename.
+  auto file_context() const -> FileContext {
+    if (source_loc_.has_value()) {
+      auto filename =
+          llvm::StringRef(source_loc_->filename()).rsplit("/").second;
+      if (filename == "prelude.carbon") {
+        return FileContext::Prelude;
+      } else {
+        return FileContext::Main;
+      }
+    } else {
+      return FileContext::Unknown;
+    }
+  };
+
   // Returns true if tracing is currently enabled.
   // TODO: use current source location for file context based filtering instead
   // of just checking if current code context is Prelude.
   auto is_enabled() const -> bool {
     return stream_.has_value() && !in_prelude_ &&
-           allowed_phases_[static_cast<int>(current_phase_)];
+           allowed_phases_[static_cast<int>(current_phase_)] &&
+           allowed_file_contexts_[static_cast<int>(file_context())];
   }
 
   // Sets whether the prelude is being skipped.
@@ -79,6 +104,29 @@ class TraceStream {
     }
   }
 
+  auto set_allowed_file_contexts(std::vector<FileContext> contexts_list)
+      -> void {
+    if (contexts_list.empty()) {
+      allowed_file_contexts_.set(static_cast<int>(FileContext::Main));
+    } else {
+      for (auto context : contexts_list) {
+        if (context == FileContext::All) {
+          allowed_file_contexts_.set();
+        } else {
+          allowed_file_contexts_.set(static_cast<int>(context));
+        }
+      }
+    }
+  }
+
+  auto set_source_loc(std::optional<SourceLocation> source_loc) {
+    source_loc_ = source_loc;
+  }
+
+  auto source_loc() -> std::optional<SourceLocation> { return source_loc_; }
+
+  auto allowed_phases() { return allowed_phases_; }
+
   // Returns the internal stream. Requires is_enabled.
   auto stream() const -> llvm::raw_ostream& {
     CARBON_CHECK(is_enabled() && stream_.has_value());
@@ -97,13 +145,15 @@ class TraceStream {
 
  private:
   bool in_prelude_ = false;
-  std::optional<Nonnull<llvm::raw_ostream*>> stream_;
   ProgramPhase current_phase_ = ProgramPhase::Unknown;
+  std::optional<SourceLocation> source_loc_ = std::nullopt;
+  std::optional<Nonnull<llvm::raw_ostream*>> stream_;
   std::bitset<static_cast<int>(ProgramPhase::Last) + 1> allowed_phases_;
+  std::bitset<static_cast<int>(FileContext::Last) + 1> allowed_file_contexts_;
 };
 
 // This is a RAII class to set the current program phase, destructor invocation
-// restores the previous phase
+// restores the previous phase.
 class SetProgramPhase {
  public:
   explicit SetProgramPhase(TraceStream& trace_stream,
@@ -113,19 +163,43 @@ class SetProgramPhase {
     trace_stream.set_current_phase(program_phase);
   }
 
+  ~SetProgramPhase() { trace_stream_.set_current_phase(initial_phase_); }
+
   // This can be used for cases when current phase is set multiple times within
-  // the same scope
+  // the same scope.
   auto update_phase(ProgramPhase program_phase) -> void {
     trace_stream_.set_current_phase(program_phase);
   }
 
-  ~SetProgramPhase() { trace_stream_.set_current_phase(initial_phase_); }
-
  private:
   TraceStream& trace_stream_;
   ProgramPhase initial_phase_;
 };
 
+// This is a RAII class to set the source location in trace stream, destructor
+// invocation restores the initial source location.
+class SetFileContext {
+ public:
+  explicit SetFileContext(TraceStream& trace_stream,
+                          std::optional<SourceLocation> source_loc)
+      : trace_stream_(trace_stream),
+        initial_source_loc_(trace_stream.source_loc()) {
+    trace_stream_.set_source_loc(source_loc);
+  }
+
+  ~SetFileContext() { trace_stream_.set_source_loc(initial_source_loc_); }
+
+  // This can be used for cases when source location needs to be updated
+  // multiple times within the same scope.
+  auto update_source_loc(std::optional<SourceLocation> source_loc) {
+    trace_stream_.set_source_loc(source_loc);
+  }
+
+ private:
+  TraceStream& trace_stream_;
+  std::optional<SourceLocation> initial_source_loc_;
+};
+
 }  // namespace Carbon
 
 #endif  // CARBON_EXPLORER_COMMON_TRACE_STREAM_H_
diff --git a/explorer/file_test.cpp b/explorer/file_test.cpp
index baa890afae59..1edf59020a21 100644
--- a/explorer/file_test.cpp
+++ b/explorer/file_test.cpp
@@ -57,6 +57,7 @@ class ParseAndExecuteTestFile : public FileTestBase {
     if (trace_) {
       trace_stream.set_stream(is_trace_test ? &stdout : &trace_stream_ostream);
       trace_stream.set_allowed_phases({ProgramPhase::All});
+      trace_stream.set_allowed_file_contexts({FileContext::Main});
     }
 
     // Set the location of the prelude.
diff --git a/explorer/interpreter/action.h b/explorer/interpreter/action.h
index eff455050e63..7772d4313112 100644
--- a/explorer/interpreter/action.h
+++ b/explorer/interpreter/action.h
@@ -165,10 +165,14 @@ class Action {
     scope_ = std::move(scope);
   }
 
+  auto source_loc() -> std::optional<SourceLocation> { return source_loc_; }
+
  protected:
   // Constructs an Action. `kind` must be the enumerator corresponding to the
   // most-derived type being constructed.
-  explicit Action(Kind kind) : kind_(kind) {}
+  explicit Action(std::optional<SourceLocation> source_loc, Kind kind)
+      : source_loc_(source_loc), kind_(kind) {}
+  std::optional<SourceLocation> source_loc_;
 
  private:
   int pos_ = 0;
@@ -183,7 +187,8 @@ class Action {
 class LocationAction : public Action {
  public:
   explicit LocationAction(Nonnull<const Expression*> expression)
-      : Action(Kind::LocationAction), expression_(expression) {}
+      : Action(expression->source_loc(), Kind::LocationAction),
+        expression_(expression) {}
 
   static auto classof(const Action* action) -> bool {
     return action->kind() == Kind::LocationAction;
@@ -202,7 +207,7 @@ class ExpressionAction : public Action {
   explicit ExpressionAction(
       Nonnull<const Expression*> expression,
       std::optional<AllocationId> initialized_location = std::nullopt)
-      : Action(Kind::ExpressionAction),
+      : Action(expression->source_loc(), Kind::ExpressionAction),
         expression_(expression),
         location_received_(initialized_location) {}
 
@@ -229,7 +234,7 @@ class TypeInstantiationAction : public Action {
  public:
   explicit TypeInstantiationAction(Nonnull<const Value*> type,
                                    SourceLocation source_loc)
-      : Action(Kind::TypeInstantiationAction),
+      : Action(source_loc, Kind::TypeInstantiationAction),
         type_(type),
         source_loc_(source_loc) {}
 
@@ -249,13 +254,19 @@ class TypeInstantiationAction : public Action {
 // local context.
 class WitnessAction : public Action {
  public:
-  explicit WitnessAction(Nonnull<const Witness*> witness)
-      : Action(Kind::WitnessAction), witness_(witness) {}
+  explicit WitnessAction(Nonnull<const Witness*> witness,
+                         SourceLocation source_loc)
+      : Action(source_loc, Kind::WitnessAction), witness_(witness) {}
 
   static auto classof(const Action* action) -> bool {
     return action->kind() == Kind::WitnessAction;
   }
 
+  auto source_loc() -> SourceLocation {
+    CARBON_CHECK(source_loc_);
+    return *source_loc_;
+  }
+
   // The Witness this Action resolves.
   auto witness() const -> Nonnull<const Witness*> { return witness_; }
 
@@ -269,7 +280,7 @@ class StatementAction : public Action {
  public:
   explicit StatementAction(Nonnull<const Statement*> statement,
                            std::optional<AllocationId> location_received)
-      : Action(Kind::StatementAction),
+      : Action(statement->source_loc(), Kind::StatementAction),
         statement_(statement),
         location_received_(location_received) {}
 
@@ -306,7 +317,8 @@ class StatementAction : public Action {
 class DeclarationAction : public Action {
  public:
   explicit DeclarationAction(Nonnull<const Declaration*> declaration)
-      : Action(Kind::DeclarationAction), declaration_(declaration) {}
+      : Action(declaration->source_loc(), Kind::DeclarationAction),
+        declaration_(declaration) {}
 
   static auto classof(const Action* action) -> bool {
     return action->kind() == Kind::DeclarationAction;
@@ -323,7 +335,7 @@ class DeclarationAction : public Action {
 class CleanUpAction : public Action {
  public:
   explicit CleanUpAction(RuntimeScope scope)
-      : Action(Kind::CleanUpAction),
+      : Action(std::nullopt, Kind::CleanUpAction),
         allocations_count_(scope.allocations().size()) {
     StartScope(std::move(scope));
   }
@@ -350,7 +362,9 @@ class DestroyAction : public Action {
   //           and the value is the member of the class
   explicit DestroyAction(Nonnull<const LocationValue*> location,
                          Nonnull<const Value*> value)
-      : Action(Kind::DestroyAction), location_(location), value_(value) {}
+      : Action(std::nullopt, Kind::DestroyAction),
+        location_(location),
+        value_(value) {}
 
   static auto classof(const Action* action) -> bool {
     return action->kind() == Kind::DestroyAction;
@@ -371,7 +385,8 @@ class DestroyAction : public Action {
 // with AST nodes.
 class ScopeAction : public Action {
  public:
-  explicit ScopeAction(RuntimeScope scope) : Action(Kind::ScopeAction) {
+  explicit ScopeAction(RuntimeScope scope)
+      : Action(std::nullopt, Kind::ScopeAction) {
     StartScope(std::move(scope));
   }
 
@@ -390,7 +405,7 @@ class ScopeAction : public Action {
 // Should be avoided where possible.
 class RecursiveAction : public Action {
  public:
-  explicit RecursiveAction() : Action(Kind::RecursiveAction) {}
+  explicit RecursiveAction() : Action(std::nullopt, Kind::RecursiveAction) {}
 
   static auto classof(const Action* action) -> bool {
     return action->kind() == Kind::RecursiveAction;
diff --git a/explorer/interpreter/exec_program.cpp b/explorer/interpreter/exec_program.cpp
index afe82e1dd15a..5c9f298724b5 100644
--- a/explorer/interpreter/exec_program.cpp
+++ b/explorer/interpreter/exec_program.cpp
@@ -24,6 +24,7 @@ auto AnalyzeProgram(Nonnull<Arena*> arena, AST ast,
                     Nonnull<TraceStream*> trace_stream,
                     Nonnull<llvm::raw_ostream*> print_stream) -> ErrorOr<AST> {
   SetProgramPhase set_prog_phase(*trace_stream, ProgramPhase::SourceProgram);
+  SetFileContext set_file_ctx(*trace_stream, std::nullopt);
 
   if (trace_stream->is_enabled()) {
     *trace_stream << "********** source program **********\n";
@@ -68,9 +69,11 @@ auto AnalyzeProgram(Nonnull<Arena*> arena, AST ast,
   set_prog_phase.update_phase(ProgramPhase::Declarations);
   if (trace_stream->is_enabled()) {
     *trace_stream << "********** printing declarations **********\n";
-    for (int i = ast.num_prelude_declarations;
-         i < static_cast<int>(ast.declarations.size()); ++i) {
-      *trace_stream << *ast.declarations[i];
+    for (auto& declaration : ast.declarations) {
+      set_file_ctx.update_source_loc(declaration->source_loc());
+      if (trace_stream->is_enabled()) {
+        *trace_stream << *declaration;
+      }
     }
   }
   return ast;
diff --git a/explorer/interpreter/interpreter.cpp b/explorer/interpreter/interpreter.cpp
index 11321c45bf31..7989e6e6f78c 100644
--- a/explorer/interpreter/interpreter.cpp
+++ b/explorer/interpreter/interpreter.cpp
@@ -24,6 +24,7 @@
 #include "explorer/common/arena.h"
 #include "explorer/common/error_builders.h"
 #include "explorer/common/source_location.h"
+#include "explorer/common/trace_stream.h"
 #include "explorer/interpreter/action.h"
 #include "explorer/interpreter/action_stack.h"
 #include "explorer/interpreter/stack.h"
@@ -163,7 +164,8 @@ class Interpreter {
 
   // Instantiate a witness by replacing all type variables and impl binding
   // references that occur within it by the current values of those variables.
-  auto InstantiateWitness(Nonnull<const Witness*> witness)
+  auto InstantiateWitness(Nonnull<const Witness*> witness,
+                          SourceLocation source_loc)
       -> ErrorOr<Nonnull<const Witness*>>;
 
   // Call the function `fun` with the given `arg` and the `witnesses`
@@ -631,9 +633,9 @@ auto Interpreter::StepLocation() -> ErrorOr<Success> {
 auto Interpreter::EvalRecursively(std::unique_ptr<Action> action)
     -> ErrorOr<Nonnull<const Value*>> {
   if (trace_stream_->is_enabled()) {
-    *trace_stream_ << "--- recursive eval\n";
     TraceState();
   }
+
   todo_.BeginRecursiveAction();
   CARBON_RETURN_IF_ERROR(todo_.Spawn(std::move(action)));
   // Note that the only `RecursiveAction` we can encounter here is our own --
@@ -661,7 +663,7 @@ auto Interpreter::EvalAssociatedConstant(
   CARBON_ASSIGN_OR_RETURN(Nonnull<const Value*> interface,
                           InstantiateType(&assoc->interface(), source_loc));
   CARBON_ASSIGN_OR_RETURN(Nonnull<const Witness*> witness,
-                          InstantiateWitness(&assoc->witness()));
+                          InstantiateWitness(&assoc->witness(), source_loc));
 
   const auto* impl_witness = dyn_cast<ImplWitness>(witness);
   if (!impl_witness) {
@@ -753,8 +755,8 @@ auto Interpreter::InstantiateBindings(Nonnull<const Bindings*> bindings,
 
   ImplWitnessMap witnesses = bindings->witnesses();
   for (auto& [bind, witness] : witnesses) {
-    CARBON_ASSIGN_OR_RETURN(witness,
-                            InstantiateWitness(cast<Witness>(witness)));
+    CARBON_ASSIGN_OR_RETURN(
+        witness, InstantiateWitness(cast<Witness>(witness), source_loc));
   }
 
   if (args == bindings->args() && witnesses == bindings->witnesses()) {
@@ -763,11 +765,12 @@ auto Interpreter::InstantiateBindings(Nonnull<const Bindings*> bindings,
   return arena_->New<Bindings>(std::move(args), std::move(witnesses));
 }
 
-auto Interpreter::InstantiateWitness(Nonnull<const Witness*> witness)
+auto Interpreter::InstantiateWitness(Nonnull<const Witness*> witness,
+                                     SourceLocation source_loc)
     -> ErrorOr<Nonnull<const Witness*>> {
   CARBON_ASSIGN_OR_RETURN(
       Nonnull<const Value*> value,
-      EvalRecursively(std::make_unique<WitnessAction>(witness)));
+      EvalRecursively(std::make_unique<WitnessAction>(witness, source_loc)));
   return cast<Witness>(value);
 }
 
@@ -1406,8 +1409,8 @@ auto Interpreter::StepExp() -> ErrorOr<Success> {
             // Next, if we're accessing an interface member, evaluate the `impl`
             // expression to find the corresponding witness.
             if (impl_has_value) {
-              return todo_.Spawn(
-                  std::make_unique<WitnessAction>(access.impl().value()));
+              return todo_.Spawn(std::make_unique<WitnessAction>(
+                  access.impl().value(), access.source_loc()));
             } else {
               return todo_.RunAgain();
             }
@@ -1504,8 +1507,8 @@ auto Interpreter::StepExp() -> ErrorOr<Success> {
             if (impl_has_value) {
               // Next, if we're accessing an interface member, evaluate the
               // `impl` expression to find the corresponding witness.
-              return todo_.Spawn(
-                  std::make_unique<WitnessAction>(access.impl().value()));
+              return todo_.Spawn(std::make_unique<WitnessAction>(
+                  access.impl().value(), access.source_loc()));
             } else {
               return todo_.RunAgain();
             }
@@ -1648,8 +1651,8 @@ auto Interpreter::StepExp() -> ErrorOr<Success> {
                  act.pos() < 2 + static_cast<int>(num_witnesses)) {
         auto iter = call.witnesses().begin();
         std::advance(iter, act.pos() - 2);
-        return todo_.Spawn(
-            std::make_unique<WitnessAction>(cast<Witness>(iter->second)));
+        return todo_.Spawn(std::make_unique<WitnessAction>(
+            cast<Witness>(iter->second), call.source_loc()));
       } else if (act.pos() == 2 + static_cast<int>(num_witnesses)) {
         //    { { v2 :: v1([]) :: C, E, F} :: S, H}
         // -> { {C',E',F'} :: {C, E, F} :: S, H}
@@ -2011,8 +2014,8 @@ auto Interpreter::StepExp() -> ErrorOr<Success> {
 }
 
 auto Interpreter::StepWitness() -> ErrorOr<Success> {
-  Action& act = todo_.CurrentAction();
-  const Witness* witness = cast<WitnessAction>(act).witness();
+  auto& act = cast<WitnessAction>(todo_.CurrentAction());
+  const Witness* witness = act.witness();
   if (trace_stream_->is_enabled()) {
     *trace_stream_ << "--- step witness " << *witness << " ." << act.pos()
                    << ". --->\n";
@@ -2036,8 +2039,8 @@ auto Interpreter::StepWitness() -> ErrorOr<Success> {
       llvm::ArrayRef<Nonnull<const Witness*>> witnesses =
           cast<ConstraintWitness>(witness)->witnesses();
       if (act.pos() < static_cast<int>(witnesses.size())) {
-        return todo_.Spawn(
-            std::make_unique<WitnessAction>(witnesses[act.pos()]));
+        return todo_.Spawn(std::make_unique<WitnessAction>(witnesses[act.pos()],
+                                                           act.source_loc()));
       }
       std::vector<Nonnull<const Witness*>> new_witnesses;
       new_witnesses.reserve(witnesses.size());
@@ -2052,7 +2055,7 @@ auto Interpreter::StepWitness() -> ErrorOr<Success> {
       const auto* constraint_impl = cast<ConstraintImplWitness>(witness);
       if (act.pos() == 0) {
         return todo_.Spawn(std::make_unique<WitnessAction>(
-            constraint_impl->constraint_witness()));
+            constraint_impl->constraint_witness(), act.source_loc()));
       }
       return todo_.FinishAction(ConstraintImplWitness::Make(
           arena_, cast<Witness>(act.results()[0]), constraint_impl->index()));
@@ -2670,7 +2673,10 @@ auto InterpProgram(const AST& ast, Nonnull<Arena*> arena,
     *trace_stream << "********** initializing globals **********\n";
   }
 
+  SetFileContext set_file_ctx(*trace_stream,
+                              ast.declarations.front()->source_loc());
   for (Nonnull<Declaration*> declaration : ast.declarations) {
+    set_file_ctx.update_source_loc(declaration->source_loc());
     CARBON_RETURN_IF_ERROR(interpreter.RunAllSteps(
         std::make_unique<DeclarationAction>(declaration)));
   }
@@ -2679,6 +2685,8 @@ auto InterpProgram(const AST& ast, Nonnull<Arena*> arena,
     *trace_stream << "********** calling main function **********\n";
   }
 
+  CARBON_CHECK(ast.main_call);
+  set_file_ctx.update_source_loc(ast.main_call.value()->source_loc());
   CARBON_RETURN_IF_ERROR(interpreter.RunAllSteps(
       std::make_unique<ExpressionAction>(*ast.main_call)));
 
diff --git a/explorer/interpreter/type_checker.cpp b/explorer/interpreter/type_checker.cpp
index 7d3ee113fb0c..572f78eff5ee 100644
--- a/explorer/interpreter/type_checker.cpp
+++ b/explorer/interpreter/type_checker.cpp
@@ -28,6 +28,7 @@
 #include "explorer/common/error_builders.h"
 #include "explorer/common/nonnull.h"
 #include "explorer/common/source_location.h"
+#include "explorer/common/trace_stream.h"
 #include "explorer/interpreter/impl_scope.h"
 #include "explorer/interpreter/interpreter.h"
 #include "explorer/interpreter/pattern_analysis.h"
@@ -1022,6 +1023,7 @@ auto TypeChecker::ImplicitlyConvert(std::string_view context,
         ConvertToConstraintType(source->source_loc(), "implicit conversion",
                                 destination));
     destination = destination_constraint;
+
     if (trace_stream_->is_enabled()) {
       *trace_stream_ << "converting type " << *converted_value
                      << " to constraint " << *destination_constraint << " for "
@@ -6326,23 +6328,15 @@ auto TypeChecker::DeclareAliasDeclaration(Nonnull<AliasDeclaration*> alias,
 auto TypeChecker::TypeCheck(AST& ast) -> ErrorOr<Success> {
   ImplScope impl_scope;
   ScopeInfo top_level_scope_info = ScopeInfo::ForNonClassScope(&impl_scope);
+  SetFileContext set_file_ctx(*trace_stream_, std::nullopt);
 
   // Track that `impl_scope` is the top-level `ImplScope`.
   llvm::SaveAndRestore<decltype(top_level_impl_scope_)>
       set_top_level_impl_scope(top_level_impl_scope_, &impl_scope);
 
-  if (trace_stream_->is_enabled()) {
-    *trace_stream_ << "Omitting prelude type checking traces...\n";
-    trace_stream_->set_in_prelude(true);
-  }
   for (int i = 0; i < static_cast<int>(ast.declarations.size()); ++i) {
-    if (i == ast.num_prelude_declarations) {
-      trace_stream_->set_in_prelude(false);
-      if (trace_stream_->is_enabled()) {
-        *trace_stream_ << "Finished prelude, resuming traces...\n";
-      }
-    }
     auto* declaration = ast.declarations[i];
+    set_file_ctx.update_source_loc(declaration->source_loc());
     CARBON_RETURN_IF_ERROR(
         DeclareDeclaration(declaration, top_level_scope_info));
     CARBON_RETURN_IF_ERROR(
diff --git a/explorer/lit_testdata/trace.carbon b/explorer/lit_testdata/trace.carbon
index 5cacba4a0f96..529300725e26 100644
--- a/explorer/lit_testdata/trace.carbon
+++ b/explorer/lit_testdata/trace.carbon
@@ -6,17 +6,17 @@
 // sanity checking on --parser_debug --trace_file=- along with filter flags output.
 //
 // NOAUTOUPDATE
-// RUN: %{explorer} --parser_debug --trace_file=- | %{FileCheck-allow-unmatched} --check-prefixes=NO-SOURCE,NO-NAMES,NO-PRELUDE,NO-FLOW,NO-TYPE,NO-UNFORMED,NO-DECLS,EXEC,NO-TIMING
-// RUN: %{explorer} --parser_debug --trace_file=- -trace_phase=execution | %{FileCheck-allow-unmatched} --check-prefixes=NO-SOURCE,NO-NAMES,NO-PRELUDE,NO-FLOW,NO-TYPE,NO-UNFORMED,NO-DECLS,EXEC,NO-TIMING
-// RUN: %{explorer} --parser_debug --trace_file=- -trace_phase=source_program | %{FileCheck-allow-unmatched} --check-prefixes=SOURCE,NO-NAMES,NO-PRELUDE,NO-FLOW,NO-TYPE,NO-UNFORMED,NO-DECLS,NO-EXEC,NO-TIMING
-// RUN: %{explorer} --parser_debug --trace_file=- -trace_phase=name_resolution | %{FileCheck-allow-unmatched} --check-prefixes=NO-SOURCE,NAMES,NO-PRELUDE,NO-FLOW,NO-TYPE,NO-UNFORMED,NO-DECLS,NO-EXEC,NO-TIMING
-// RUN: %{explorer} --parser_debug --trace_file=- -trace_phase=control_flow_resolution | %{FileCheck-allow-unmatched} --check-prefixes=NO-SOURCE,NO-NAMES,NO-PRELUDE,FLOW,NO-TYPE,NO-UNFORMED,NO-DECLS,NO-EXEC,NO-TIMING
-// RUN: %{explorer} --parser_debug --trace_file=- -trace_phase=type_checking | %{FileCheck-allow-unmatched} --check-prefixes=NO-SOURCE,NO-NAMES,NO-PRELUDE,NO-FLOW,TYPE,NO-UNFORMED,NO-DECLS,NO-EXEC,NO-TIMING
-// RUN: %{explorer} --parser_debug --trace_file=- -trace_phase=unformed_variables_resolution | %{FileCheck-allow-unmatched} --check-prefixes=NO-SOURCE,NO-NAMES,NO-PRELUDE,NO-FLOW,NO-TYPE,UNFORMED,NO-DECLS,NO-EXEC,NO-TIMING
-// RUN: %{explorer} --parser_debug --trace_file=- -trace_phase=declarations | %{FileCheck-allow-unmatched} --check-prefixes=NO-SOURCE,NO-NAMES,NO-PRELUDE,NO-FLOW,NO-TYPE,NO-UNFORMED,DECLS,NO-EXEC,NO-TIMING
-// RUN: %{explorer} --parser_debug --trace_file=- -trace_phase=timing | %{FileCheck-allow-unmatched} --check-prefixes=NO-SOURCE,NO-NAMES,NO-PRELUDE,NO-FLOW,NO-TYPE,NO-UNFORMED,NO-DECLS,NO-EXEC,TIMING
-// RUN: %{explorer} --parser_debug --trace_file=- -trace_phase=all | %{FileCheck-allow-unmatched} --check-prefixes=SOURCE,NAMES,NO-PRELUDE,FLOW,TYPE,UNFORMED,DECLS,EXEC,TIMING
-// RUN: %{explorer} --parser_debug --trace_file=- -trace_phase=source_program,declarations | %{FileCheck-allow-unmatched} --check-prefixes=SOURCE,NO-NAMES,NO-PRELUDE,NO-FLOW,NO-TYPE,NO-UNFORMED,DECLS,NO-EXEC,NO-TIMING
+// RUN: %{explorer} --parser_debug --trace_file=- -trace_file_context=all | %{FileCheck-allow-unmatched} --check-prefixes=NO-SOURCE,NO-NAMES,NO-PRELUDE,NO-FLOW,NO-TYPE,NO-UNFORMED,NO-DECLS,EXEC,NO-TIMING
+// RUN: %{explorer} --parser_debug --trace_file=- -trace_file_context=all -trace_phase=execution | %{FileCheck-allow-unmatched} --check-prefixes=NO-SOURCE,NO-NAMES,NO-PRELUDE,NO-FLOW,NO-TYPE,NO-UNFORMED,NO-DECLS,EXEC,NO-TIMING
+// RUN: %{explorer} --parser_debug --trace_file=- -trace_file_context=all -trace_phase=source_program | %{FileCheck-allow-unmatched} --check-prefixes=SOURCE,NO-NAMES,NO-PRELUDE,NO-FLOW,NO-TYPE,NO-UNFORMED,NO-DECLS,NO-EXEC,NO-TIMING
+// RUN: %{explorer} --parser_debug --trace_file=- -trace_file_context=all -trace_phase=name_resolution | %{FileCheck-allow-unmatched} --check-prefixes=NO-SOURCE,NAMES,NO-PRELUDE,NO-FLOW,NO-TYPE,NO-UNFORMED,NO-DECLS,NO-EXEC,NO-TIMING
+// RUN: %{explorer} --parser_debug --trace_file=- -trace_file_context=all -trace_phase=control_flow_resolution | %{FileCheck-allow-unmatched} --check-prefixes=NO-SOURCE,NO-NAMES,NO-PRELUDE,FLOW,NO-TYPE,NO-UNFORMED,NO-DECLS,NO-EXEC,NO-TIMING
+// RUN: %{explorer} --parser_debug --trace_file=- -trace_file_context=all -trace_phase=type_checking | %{FileCheck-allow-unmatched} --check-prefixes=NO-SOURCE,NO-NAMES,NO-PRELUDE,NO-FLOW,TYPE,NO-UNFORMED,NO-DECLS,NO-EXEC,NO-TIMING
+// RUN: %{explorer} --parser_debug --trace_file=- -trace_file_context=all -trace_phase=unformed_variables_resolution | %{FileCheck-allow-unmatched} --check-prefixes=NO-SOURCE,NO-NAMES,NO-PRELUDE,NO-FLOW,NO-TYPE,UNFORMED,NO-DECLS,NO-EXEC,NO-TIMING
+// RUN: %{explorer} --parser_debug --trace_file=- -trace_file_context=all -trace_phase=declarations | %{FileCheck-allow-unmatched} --check-prefixes=NO-SOURCE,NO-NAMES,NO-PRELUDE,NO-FLOW,NO-TYPE,NO-UNFORMED,DECLS,NO-EXEC,NO-TIMING
+// RUN: %{explorer} --parser_debug --trace_file=- -trace_file_context=all -trace_phase=timing | %{FileCheck-allow-unmatched} --check-prefixes=NO-SOURCE,NO-NAMES,NO-PRELUDE,NO-FLOW,NO-TYPE,NO-UNFORMED,NO-DECLS,NO-EXEC,TIMING
+// RUN: %{explorer} --parser_debug --trace_file=- -trace_file_context=all -trace_phase=all | %{FileCheck-allow-unmatched} --check-prefixes=SOURCE,NAMES,NO-PRELUDE,FLOW,TYPE,UNFORMED,DECLS,EXEC,TIMING
+// RUN: %{explorer} --parser_debug --trace_file=- -trace_file_context=all -trace_phase=source_program,declarations | %{FileCheck-allow-unmatched} --check-prefixes=SOURCE,NO-NAMES,NO-PRELUDE,NO-FLOW,NO-TYPE,NO-UNFORMED,DECLS,NO-EXEC,NO-TIMING
 // NO-SOURCE-NOT:STDOUT: ********** source program **********
 //        SOURCE:STDOUT: ********** source program **********
 // NO-SOURCE-NOT:STDOUT: interface TestInterface {
diff --git a/explorer/lit_testdata/trace_file_filters.carbon b/explorer/lit_testdata/trace_file_filters.carbon
new file mode 100644
index 000000000000..dc75164af8bc
--- /dev/null
+++ b/explorer/lit_testdata/trace_file_filters.carbon
@@ -0,0 +1,31 @@
+// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
+// Exceptions. See /LICENSE for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+// A lot of output is elided: this is only checking for a few things for simple
+// sanity checking on --parser_debug --trace_file=- along with file context
+// filter flags output.
+//
+// NOAUTOUPDATE
+// RUN: %{explorer} --parser_debug --trace_file=- -trace_phase=all -trace_file_context=main | %{FileCheck-allow-unmatched} --check-prefixes=MAIN,NO-PRELUDE
+// RUN: %{explorer} --parser_debug --trace_file=- -trace_phase=all -trace_file_context=prelude | %{FileCheck-allow-unmatched} --check-prefixes=NO-MAIN,PRELUDE
+// RUN: %{explorer} --parser_debug --trace_file=- -trace_phase=all -trace_file_context=all | %{FileCheck-allow-unmatched} --check-prefixes=MAIN,PRELUDE
+// RUN: %{explorer} --parser_debug --trace_file=- -trace_phase=all -trace_file_context=main,prelude | %{FileCheck-allow-unmatched} --check-prefixes=MAIN,PRELUDE
+// NO-PRELUDE-NOT:STDOUT: ** declaring interface As
+//        PRELUDE:STDOUT: ** declaring interface As
+// NO-MAIN-NOT:STDOUT: ** declaring function Main
+//        MAIN:STDOUT: ** declaring function Main
+// NO-PRELUDE-NOT:STDOUT: interface As {
+//        PRELUDE:STDOUT: interface As {
+// NO-MAIN-NOT:STDOUT: fn Main ()-> i32 {
+//        MAIN:STDOUT: fn Main ()-> i32 {
+// NO-MAIN-NOT:STDOUT: --- step exp Main() .0. (<Main()>:0) --->
+//        MAIN:STDOUT: --- step exp Main() .0. (<Main()>:0) --->
+
+package ExplorerTest api;
+
+interface TestInterface {}
+
+fn Main() -> i32 {
+  return 0;
+}
diff --git a/explorer/main.cpp b/explorer/main.cpp
index 53c56d0345ce..4f26fccb0dc1 100644
--- a/explorer/main.cpp
+++ b/explorer/main.cpp
@@ -81,6 +81,22 @@ auto ExplorerMain(int argc, char** argv, void* static_for_main_addr,
                      "Include trace output for all phases.")),
       cl::CommaSeparated);
 
+  cl::list<FileContext> allowed_file_contexts(
+      "trace_file_context",
+      cl::desc("Select file contexts for which you want to include the trace "
+               "output"),
+      cl::values(
+          clEnumValN(
+              FileContext::Main, "main",
+              "Include trace output for file containing the main function"),
+          clEnumValN(FileContext::Prelude, "prelude",
+                     "Include trace output for prelude"),
+          clEnumValN(FileContext::Import, "import",
+                     "Include trace output for imports"),
+          clEnumValN(FileContext::All, "all",
+                     "Include trace output for all files")),
+      cl::CommaSeparated);
+
   // Use the executable path as a base for the relative prelude path.
   std::string exe =
       llvm::sys::fs::getMainExecutable(argv[0], static_for_main_addr);
@@ -102,6 +118,7 @@ auto ExplorerMain(int argc, char** argv, void* static_for_main_addr,
   if (!trace_file_name.empty()) {
     // Adding allowed phases in the trace_stream
     trace_stream.set_allowed_phases(allowed_program_phases);
+    trace_stream.set_allowed_file_contexts(allowed_file_contexts);
     if (trace_file_name == "-") {
       trace_stream.set_stream(&llvm::outs());
     } else {
diff --git a/explorer/trace_testdata/full_trace.carbon b/explorer/trace_testdata/full_trace.carbon
index 6ed986171726..d7a9f5b89795 100644
--- a/explorer/trace_testdata/full_trace.carbon
+++ b/explorer/trace_testdata/full_trace.carbon
@@ -15,8 +15,6 @@
 // CHECK:STDOUT: ********** resolving names **********
 // CHECK:STDOUT: ********** resolving control flow **********
 // CHECK:STDOUT: ********** type checking **********
-// CHECK:STDOUT: Omitting prelude type checking traces...
-// CHECK:STDOUT: Finished prelude, resuming traces...
 // CHECK:STDOUT: ** declaring interface TestInterface
 // CHECK:STDOUT: ** finished declaring interface TestInterface
 // CHECK:STDOUT: checking InterfaceDeclaration
@@ -37,7 +35,7 @@ package ExplorerTest api;
 
 interface TestInterface {}
 
-// CHECK:STDOUT: --- step exp i32 .0. (full_trace.carbon:[[@LINE+1184]]) --->
+// CHECK:STDOUT: --- step exp i32 .0. (full_trace.carbon:[[@LINE+49]]) --->
 // CHECK:STDOUT: {
 // CHECK:STDOUT: stack:{{ }}
 // CHECK:STDOUT: memory:{{ }}
@@ -75,1144 +73,9 @@ interface TestInterface {}
 // CHECK:STDOUT: ********** initializing globals **********
 // CHECK:STDOUT: {
 // CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface As .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface ImplicitAs .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface __EqualConverter .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl fn __EqualConvert .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl forall [U:! type] U as __EqualConverter where .T = U .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl match_first .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl forall [U1:! type, T1:! As(U1)] (T1) as As((U1)) .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl forall [U1:! type, U2:! type, T1:! As(U1), T2:! As(U2)] (T1, T2) as As((U1, U2)) .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl forall [U1:! type, U2:! type, U3:! type, T1:! As(U1), T2:! As(U2), T3:! As(U3)] (T1, T2, T3) as As((U1, U2, U3)) .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface EqWith .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl constraint Eq .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl forall [T2:! type, U2:! type, T1:! EqWith(T2), U1:! EqWith(U2)] (T1, U1) as EqWith((T2, U2)) .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl bool as EqWith(Self) .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl i32 as EqWith(Self) .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl String as EqWith(Self) .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl choice Ordering .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface CompareWith .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl constraint Ordered .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl i32 as CompareWith(Self) .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl String as CompareWith(Self) .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface LessWith .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface LessEqWith .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface GreaterWith .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface GreaterEqWith .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl i32 as LessWith(Self) .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl String as LessWith(Self) .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl i32 as LessEqWith(Self) .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl String as LessEqWith(Self) .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl i32 as GreaterWith(Self) .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl String as GreaterWith(Self) .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl i32 as GreaterEqWith(Self) .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl String as GreaterEqWith(Self) .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface Negate .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface AddWith .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl constraint Add .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface SubWith .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl constraint Sub .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface MulWith .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl constraint Mul .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface DivWith .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl constraint Div .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface ModWith .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl constraint Mod .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl i32 as Negate where .Result = i32 .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl i32 as AddWith(i32) where .Result = i32 .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl i32 as SubWith(i32) where .Result = i32 .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl i32 as MulWith(i32) where .Result = i32 .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl i32 as DivWith(i32) where .Result = i32 .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl i32 as ModWith(i32) where .Result = i32 .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface BitComplement .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface BitAndWith .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl constraint BitAnd .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface BitOrWith .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl constraint BitOr .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface BitXorWith .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl constraint BitXor .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface LeftShiftWith .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl constraint LeftShift .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface RightShiftWith .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl constraint RightShift .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl i32 as BitComplement where .Result = i32 .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl i32 as BitAndWith(i32) where .Result = i32 .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl i32 as BitOrWith(i32) where .Result = i32 .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl i32 as BitXorWith(i32) where .Result = i32 .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl i32 as LeftShiftWith(i32) where .Result = i32 .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl i32 as RightShiftWith(i32) where .Result = i32 .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface AssignWith .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl constraint Assign .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface AddAssignWith .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl constraint AddAssign .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface SubAssignWith .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl constraint SubAssign .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface MulAssignWith .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl constraint MulAssign .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface DivAssignWith .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl constraint DivAssign .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface ModAssignWith .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl constraint ModAssign .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface BitAndAssignWith .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl constraint BitAssignAnd .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface BitOrAssignWith .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl constraint BitAssignOr .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface BitXorAssignWith .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl constraint BitAssignXor .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface LeftShiftAssignWith .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl constraint LeftShiftAssign .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface RightShiftAssignWith .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl constraint RightShiftAssign .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl forall [T:! type, U:! ImplicitAs(T)] T as AssignWith(U) .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl forall [U:! type, T:! AddWith(U) where .Self impls AssignWith(.Self.Result)] T as AddAssignWith(U) .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl forall [U:! type, T:! SubWith(U) where .Self impls AssignWith(.Self.Result)] T as SubAssignWith(U) .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl forall [U:! type, T:! MulWith(U) where .Self impls AssignWith(.Self.Result)] T as MulAssignWith(U) .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl forall [U:! type, T:! DivWith(U) where .Self impls AssignWith(.Self.Result)] T as DivAssignWith(U) .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl forall [U:! type, T:! ModWith(U) where .Self impls AssignWith(.Self.Result)] T as ModAssignWith(U) .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl forall [U:! type, T:! BitAndWith(U) where .Self impls AssignWith(.Self.Result)] T as BitAndAssignWith(U) .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl forall [U:! type, T:! BitOrWith(U) where .Self impls AssignWith(.Self.Result)] T as BitOrAssignWith(U) .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl forall [U:! type, T:! BitXorWith(U) where .Self impls AssignWith(.Self.Result)] T as BitXorAssignWith(U) .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl forall [U:! type, T:! LeftShiftWith(U) where .Self impls AssignWith(.Self.Result)] T as LeftShiftAssignWith(U) .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl forall [U:! type, T:! RightShiftWith(U) where .Self impls AssignWith(.Self.Result)] T as RightShiftAssignWith(U) .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface Inc .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface Dec .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl i32 as Inc .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl impl i32 as Dec .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl fn Assert .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl fn Rand .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl choice OptionalElement .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl class Optional .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl class Heap .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl var heap: Heap .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack: {}.(interface ImplicitAs(T = class Heap).Convert)() .0. ## var heap: Heap = {}.(interface ImplicitAs(T = class Heap).Convert)();
-// CHECK:STDOUT:  .1.
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step exp {}.(interface ImplicitAs(T = class Heap).Convert)() .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack: {}.(interface ImplicitAs(T = class Heap).Convert) .0. ## {}.(interface ImplicitAs(T = class Heap).Convert)() .1. ## var heap: Heap = {}.(interface ImplicitAs(T = class Heap).Convert)();
-// CHECK:STDOUT:  .1.
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step exp {}.(interface ImplicitAs(T = class Heap).Convert) .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack: {} .0. ## {}.(interface ImplicitAs(T = class Heap).Convert) .1. ## {}.(interface ImplicitAs(T = class Heap).Convert)() .1. ## var heap: Heap = {}.(interface ImplicitAs(T = class Heap).Convert)();
-// CHECK:STDOUT:  .1.
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step exp {} .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack: {}.(interface ImplicitAs(T = class Heap).Convert) .1. {{[[][[]}}{}]] ## {}.(interface ImplicitAs(T = class Heap).Convert)() .1. ## var heap: Heap = {}.(interface ImplicitAs(T = class Heap).Convert)();
-// CHECK:STDOUT:  .1.
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step exp {}.(interface ImplicitAs(T = class Heap).Convert) .1. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack: witness for impl T as ImplicitAs(U) .0. ## {}.(interface ImplicitAs(T = class Heap).Convert) .2. {{[[][[]}}{}]] ## {}.(interface ImplicitAs(T = class Heap).Convert)() .1. ## var heap: Heap = {}.(interface ImplicitAs(T = class Heap).Convert)();
-// CHECK:STDOUT:  .1.
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step witness witness for impl T as ImplicitAs(U) .0. --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack: {}.(interface ImplicitAs(T = class Heap).Convert) .2. {{[[][[]}}{}, witness for impl T as ImplicitAs(U)]] ## {}.(interface ImplicitAs(T = class Heap).Convert)() .1. ## var heap: Heap = {}.(interface ImplicitAs(T = class Heap).Convert)();
-// CHECK:STDOUT:  .1.
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step exp {}.(interface ImplicitAs(T = class Heap).Convert) .2. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack: interface As(T = class Heap) .0. ## {}.(interface ImplicitAs(T = class Heap).Convert) .3. {{[[][[]}}{}, witness for impl T as ImplicitAs(U)]] ## {}.(interface ImplicitAs(T = class Heap).Convert)() .1. ## var heap: Heap = {}.(interface ImplicitAs(T = class Heap).Convert)();
-// CHECK:STDOUT:  .1.
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack: {}.(interface ImplicitAs(T = class Heap).Convert) .3. {{[[][[]}}{}, witness for impl T as ImplicitAs(U), interface As(T = class Heap)]] ## {}.(interface ImplicitAs(T = class Heap).Convert)() .1. ## var heap: Heap = {}.(interface ImplicitAs(T = class Heap).Convert)();
-// CHECK:STDOUT:  .1.
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step exp {}.(interface ImplicitAs(T = class Heap).Convert) .3. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack: {}.(interface ImplicitAs(T = class Heap).Convert) .4. {{[[][[]}}{}, witness for impl T as ImplicitAs(U), interface As(T = class Heap)]] ## {}.(interface ImplicitAs(T = class Heap).Convert)() .1. ## var heap: Heap = {}.(interface ImplicitAs(T = class Heap).Convert)();
-// CHECK:STDOUT:  .1.
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step exp {}.(interface ImplicitAs(T = class Heap).Convert) .4. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack: {}.(interface ImplicitAs(T = class Heap).Convert)() .1. {{[[][[]}}bound_method<Convert>]] ## var heap: Heap = {}.(interface ImplicitAs(T = class Heap).Convert)();
-// CHECK:STDOUT:  .1.
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step exp {}.(interface ImplicitAs(T = class Heap).Convert)() .1. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack: () .0. ## {}.(interface ImplicitAs(T = class Heap).Convert)() .2. {{[[][[]}}bound_method<Convert>]] ## var heap: Heap = {}.(interface ImplicitAs(T = class Heap).Convert)();
-// CHECK:STDOUT:  .1.
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step exp () .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack: {}.(interface ImplicitAs(T = class Heap).Convert)() .2. {{[[][[]}}bound_method<Convert>, ()]] ## var heap: Heap = {}.(interface ImplicitAs(T = class Heap).Convert)();
-// CHECK:STDOUT:  .1.
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step exp {}.(interface ImplicitAs(T = class Heap).Convert)() .2. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: calling function: bound_method<Convert>
-// CHECK:STDOUT: match pattern ()
-// CHECK:STDOUT: from value expression with value ()
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack: {return __intrinsic_implicit_as_convert(self, U);} .0. ## .0. {self: Self: {}} ## {}.(interface ImplicitAs(T = class Heap).Convert)() .3. {{[[][[]}}bound_method<Convert>, ()]] {} ## var heap: Heap = {}.(interface ImplicitAs(T = class Heap).Convert)();
-// CHECK:STDOUT:  .1.
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step stmt {return __intrinsic_implicit_as_convert(self, U);} .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack: return __intrinsic_implicit_as_convert(self, U); .0. ## {return __intrinsic_implicit_as_convert(self, U);} .1. {} ## .0. {self: Self: {}} ## {}.(interface ImplicitAs(T = class Heap).Convert)() .3. {{[[][[]}}bound_method<Convert>, ()]] {} ## var heap: Heap = {}.(interface ImplicitAs(T = class Heap).Convert)();
-// CHECK:STDOUT:  .1.
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step stmt return __intrinsic_implicit_as_convert(self, U); .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack: __intrinsic_implicit_as_convert(self, U) .0. ## return __intrinsic_implicit_as_convert(self, U); .1. ## {return __intrinsic_implicit_as_convert(self, U);} .1. {} ## .0. {self: Self: {}} ## {}.(interface ImplicitAs(T = class Heap).Convert)() .3. {{[[][[]}}bound_method<Convert>, ()]] {} ## var heap: Heap = {}.(interface ImplicitAs(T = class Heap).Convert)();
-// CHECK:STDOUT:  .1.
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step exp __intrinsic_implicit_as_convert(self, U) .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack: self .0. ## return __intrinsic_implicit_as_convert(self, U); .1. ## {return __intrinsic_implicit_as_convert(self, U);} .1. {} ## .0. {self: Self: {}} ## {}.(interface ImplicitAs(T = class Heap).Convert)() .3. {{[[][[]}}bound_method<Convert>, ()]] {} ## var heap: Heap = {}.(interface ImplicitAs(T = class Heap).Convert)();
-// CHECK:STDOUT:  .1.
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step exp self .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack: self .0. ## self .1. ## return __intrinsic_implicit_as_convert(self, U); .1. ## {return __intrinsic_implicit_as_convert(self, U);} .1. {} ## .0. {self: Self: {}} ## {}.(interface ImplicitAs(T = class Heap).Convert)() .3. {{[[][[]}}bound_method<Convert>, ()]] {} ## var heap: Heap = {}.(interface ImplicitAs(T = class Heap).Convert)();
-// CHECK:STDOUT:  .1.
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step exp self .0. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack: self .1. {{[[][[]}}{}]] ## return __intrinsic_implicit_as_convert(self, U); .1. ## {return __intrinsic_implicit_as_convert(self, U);} .1. {} ## .0. {self: Self: {}} ## {}.(interface ImplicitAs(T = class Heap).Convert)() .3. {{[[][[]}}bound_method<Convert>, ()]] {} ## var heap: Heap = {}.(interface ImplicitAs(T = class Heap).Convert)();
-// CHECK:STDOUT:  .1.
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step exp self .1. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack: class Heap .0. ## self .2. {{[[][[]}}{}]] ## return __intrinsic_implicit_as_convert(self, U); .1. ## {return __intrinsic_implicit_as_convert(self, U);} .1. {} ## .0. {self: Self: {}} ## {}.(interface ImplicitAs(T = class Heap).Convert)() .3. {{[[][[]}}bound_method<Convert>, ()]] {} ## var heap: Heap = {}.(interface ImplicitAs(T = class Heap).Convert)();
-// CHECK:STDOUT:  .1.
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack: self .2. {{[[][[]}}{}, class Heap]] ## return __intrinsic_implicit_as_convert(self, U); .1. ## {return __intrinsic_implicit_as_convert(self, U);} .1. {} ## .0. {self: Self: {}} ## {}.(interface ImplicitAs(T = class Heap).Convert)() .3. {{[[][[]}}bound_method<Convert>, ()]] {} ## var heap: Heap = {}.(interface ImplicitAs(T = class Heap).Convert)();
-// CHECK:STDOUT:  .1.
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step exp self .2. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack: return __intrinsic_implicit_as_convert(self, U); .1. {{[[][[]}}Heap{}]] ## {return __intrinsic_implicit_as_convert(self, U);} .1. {} ## .0. {self: Self: {}} ## {}.(interface ImplicitAs(T = class Heap).Convert)() .3. {{[[][[]}}bound_method<Convert>, ()]] {} ## var heap: Heap = {}.(interface ImplicitAs(T = class Heap).Convert)();
-// CHECK:STDOUT:  .1.
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step stmt return __intrinsic_implicit_as_convert(self, U); .1. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack: clean up.0. {} ## clean up.0. {self: Self: {}} ## {}.(interface ImplicitAs(T = class Heap).Convert)() .3. {{[[][[]}}bound_method<Convert>, (), Heap{}]] {} ## var heap: Heap = {}.(interface ImplicitAs(T = class Heap).Convert)();
-// CHECK:STDOUT:  .1.
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack: clean up.0. {self: Self: {}} ## {}.(interface ImplicitAs(T = class Heap).Convert)() .3. {{[[][[]}}bound_method<Convert>, (), Heap{}]] {} ## var heap: Heap = {}.(interface ImplicitAs(T = class Heap).Convert)();
-// CHECK:STDOUT:  .1.
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack: {}.(interface ImplicitAs(T = class Heap).Convert)() .3. {{[[][[]}}bound_method<Convert>, (), Heap{}]] {} ## var heap: Heap = {}.(interface ImplicitAs(T = class Heap).Convert)();
-// CHECK:STDOUT:  .1.
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step exp {}.(interface ImplicitAs(T = class Heap).Convert)() .3. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack: clean up.0. {} ## var heap: Heap = {}.(interface ImplicitAs(T = class Heap).Convert)();
-// CHECK:STDOUT:  .1. {{[[][[]}}Heap{}]]
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack: var heap: Heap = {}.(interface ImplicitAs(T = class Heap).Convert)();
-// CHECK:STDOUT:  .1. {{[[][[]}}Heap{}]]
-// CHECK:STDOUT: memory:{{ }}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl var heap: Heap .1. ({{.*}}/explorer/data/prelude.carbon:{{.*}}) --->
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
 // CHECK:STDOUT: memory: 0: Heap{}
 // CHECK:STDOUT: }
-// CHECK:STDOUT: {
-// CHECK:STDOUT: stack:{{ }}
-// CHECK:STDOUT: memory: 0: Heap{}
-// CHECK:STDOUT: }
-// CHECK:STDOUT: --- step decl interface TestInterface .0. (full_trace.carbon:[[@LINE-1177]]) --->
+// CHECK:STDOUT: --- step decl interface TestInterface .0. (full_trace.carbon:[[@LINE-42]]) --->
 // CHECK:STDOUT: {
 // CHECK:STDOUT: stack:{{ }}
 // CHECK:STDOUT: memory: 0: Heap{}