From 962defd1e8a792b3477804f30fedce99f3cf065d Mon Sep 17 00:00:00 2001
From: Jon Ross-Perkins <jperkins@google.com>
Date: Fri, 1 Dec 2023 16:44:57 -0800
Subject: [PATCH] Associate a name with ClassDecl (#3447)

Note generics will probably need different behavior.

---------

Co-authored-by: Richard Smith <richard@metafoo.co.uk>
---
 .../array/fail_incomplete_element.carbon      |  2 +-
 toolchain/check/testdata/as/identity.carbon   |  2 +-
 toolchain/check/testdata/as/tuple.carbon      |  2 +-
 toolchain/check/testdata/class/basic.carbon   |  2 +-
 .../check/testdata/class/fail_abstract.carbon |  2 +-
 .../testdata/class/fail_addr_not_self.carbon  |  2 +-
 .../testdata/class/fail_addr_self.carbon      |  2 +-
 .../testdata/class/fail_incomplete.carbon     |  2 +-
 .../check/testdata/class/fail_init.carbon     |  2 +-
 .../class/fail_init_as_inplace.carbon         |  2 +-
 .../class/fail_memaccess_category.carbon      |  4 +--
 .../testdata/class/fail_member_of_let.carbon  |  2 +-
 .../check/testdata/class/fail_method.carbon   |  2 +-
 .../fail_redeclaration_introducer.carbon      | 30 +++++++++----------
 .../class/fail_redeclaration_scope.carbon     | 24 +++++++--------
 .../testdata/class/fail_redefinition.carbon   |  4 +--
 .../check/testdata/class/fail_reorder.carbon  |  2 +-
 .../check/testdata/class/fail_scope.carbon    |  2 +-
 .../check/testdata/class/fail_self.carbon     |  4 +--
 .../testdata/class/fail_unbound_field.carbon  |  2 +-
 .../testdata/class/fail_unknown_member.carbon |  2 +-
 .../check/testdata/class/field_access.carbon  |  2 +-
 .../class/field_access_in_value.carbon        |  2 +-
 .../testdata/class/forward_declared.carbon    |  2 +-
 toolchain/check/testdata/class/init.carbon    |  2 +-
 toolchain/check/testdata/class/init_as.carbon |  2 +-
 .../check/testdata/class/init_nested.carbon   |  4 +--
 toolchain/check/testdata/class/method.carbon  |  2 +-
 toolchain/check/testdata/class/nested.carbon  |  6 ++--
 .../check/testdata/class/nested_name.carbon   |  6 ++--
 .../check/testdata/class/raw_self.carbon      |  2 +-
 .../check/testdata/class/raw_self_type.carbon |  2 +-
 .../check/testdata/class/redeclaration.carbon |  4 +--
 .../class/redeclaration_introducer.carbon     | 12 ++++----
 .../check/testdata/class/reenter_scope.carbon |  2 +-
 toolchain/check/testdata/class/scope.carbon   |  2 +-
 toolchain/check/testdata/class/self.carbon    |  2 +-
 .../check/testdata/class/self_type.carbon     |  2 +-
 .../check/testdata/class/static_method.carbon |  2 +-
 .../if_expr/fail_not_in_function.carbon       |  2 +-
 .../fail_return_with_returned_var.carbon      |  2 +-
 .../check/testdata/return/returned_var.carbon |  2 +-
 .../struct/fail_nested_incomplete.carbon      |  2 +-
 .../tuples/fail_nested_incomplete.carbon      |  2 +-
 .../testdata/var/fail_not_copyable.carbon     |  2 +-
 toolchain/sem_ir/formatter.cpp                | 12 ++++++++
 46 files changed, 96 insertions(+), 84 deletions(-)

diff --git a/toolchain/check/testdata/array/fail_incomplete_element.carbon b/toolchain/check/testdata/array/fail_incomplete_element.carbon
index 9bb41f23147d..a5a8a268f493 100644
--- a/toolchain/check/testdata/array/fail_incomplete_element.carbon
+++ b/toolchain/check/testdata/array/fail_incomplete_element.carbon
@@ -26,7 +26,7 @@ var p: Incomplete* = &a[0];
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Incomplete, ()
+// CHECK:STDOUT:   %Incomplete.decl = class_decl @Incomplete, ()
 // CHECK:STDOUT:   %Incomplete: type = class_type @Incomplete
 // CHECK:STDOUT:   %Incomplete.ref.loc15: type = name_ref Incomplete, %Incomplete
 // CHECK:STDOUT:   %.loc15_21: i32 = int_literal 1
diff --git a/toolchain/check/testdata/as/identity.carbon b/toolchain/check/testdata/as/identity.carbon
index a47a70da3523..48d0e1292dc4 100644
--- a/toolchain/check/testdata/as/identity.carbon
+++ b/toolchain/check/testdata/as/identity.carbon
@@ -33,7 +33,7 @@ fn Initializing() {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @X, ()
+// CHECK:STDOUT:   %X.decl = class_decl @X, ()
 // CHECK:STDOUT:   %X: type = class_type @X
 // CHECK:STDOUT:   %Value: <function> = fn_decl @Value
 // CHECK:STDOUT:   %Reference: <function> = fn_decl @Reference
diff --git a/toolchain/check/testdata/as/tuple.carbon b/toolchain/check/testdata/as/tuple.carbon
index aca1a2cf081e..fe1c4162d461 100644
--- a/toolchain/check/testdata/as/tuple.carbon
+++ b/toolchain/check/testdata/as/tuple.carbon
@@ -33,7 +33,7 @@ fn Var() {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @X, ()
+// CHECK:STDOUT:   %X.decl = class_decl @X, ()
 // CHECK:STDOUT:   %X: type = class_type @X
 // CHECK:STDOUT:   %Make: <function> = fn_decl @Make
 // CHECK:STDOUT:   %Let: <function> = fn_decl @Let
diff --git a/toolchain/check/testdata/class/basic.carbon b/toolchain/check/testdata/class/basic.carbon
index f5bf5372a79d..557393369a63 100644
--- a/toolchain/check/testdata/class/basic.carbon
+++ b/toolchain/check/testdata/class/basic.carbon
@@ -29,7 +29,7 @@ fn Run() -> i32 {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Class, ()
+// CHECK:STDOUT:   %Class.decl = class_decl @Class, ()
 // CHECK:STDOUT:   %Class: type = class_type @Class
 // CHECK:STDOUT:   %G: <function> = fn_decl @G
 // CHECK:STDOUT:   %Run: <function> = fn_decl @Run
diff --git a/toolchain/check/testdata/class/fail_abstract.carbon b/toolchain/check/testdata/class/fail_abstract.carbon
index 5a21212b8221..8b777ad3a794 100644
--- a/toolchain/check/testdata/class/fail_abstract.carbon
+++ b/toolchain/check/testdata/class/fail_abstract.carbon
@@ -23,7 +23,7 @@ fn Make() -> Class {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Class, ()
+// CHECK:STDOUT:   %Class.decl = class_decl @Class, ()
 // CHECK:STDOUT:   %Class: type = class_type @Class
 // CHECK:STDOUT:   %Make: <function> = fn_decl @Make
 // CHECK:STDOUT: }
diff --git a/toolchain/check/testdata/class/fail_addr_not_self.carbon b/toolchain/check/testdata/class/fail_addr_not_self.carbon
index 27d357078eca..6e92eff9a9a7 100644
--- a/toolchain/check/testdata/class/fail_addr_not_self.carbon
+++ b/toolchain/check/testdata/class/fail_addr_not_self.carbon
@@ -23,7 +23,7 @@ class Class {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Class, ()
+// CHECK:STDOUT:   %Class.decl = class_decl @Class, ()
 // CHECK:STDOUT:   %Class: type = class_type @Class
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
diff --git a/toolchain/check/testdata/class/fail_addr_self.carbon b/toolchain/check/testdata/class/fail_addr_self.carbon
index 7396eb9f67c2..081430b11ee5 100644
--- a/toolchain/check/testdata/class/fail_addr_self.carbon
+++ b/toolchain/check/testdata/class/fail_addr_self.carbon
@@ -47,7 +47,7 @@ fn F(c: Class, p: Class*) {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Class, ()
+// CHECK:STDOUT:   %Class.decl = class_decl @Class, ()
 // CHECK:STDOUT:   %Class: type = class_type @Class
 // CHECK:STDOUT:   %F: <function> = fn_decl @F.2
 // CHECK:STDOUT: }
diff --git a/toolchain/check/testdata/class/fail_incomplete.carbon b/toolchain/check/testdata/class/fail_incomplete.carbon
index ca0d465ea3a8..4f1707e115ae 100644
--- a/toolchain/check/testdata/class/fail_incomplete.carbon
+++ b/toolchain/check/testdata/class/fail_incomplete.carbon
@@ -123,7 +123,7 @@ fn CallReturnIncomplete() {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Class, ()
+// CHECK:STDOUT:   %Class.decl = class_decl @Class, ()
 // CHECK:STDOUT:   %Class: type = class_type @Class
 // CHECK:STDOUT:   %.loc15: <function> = fn_decl @.1
 // CHECK:STDOUT:   %CallClassFunction: <function> = fn_decl @CallClassFunction
diff --git a/toolchain/check/testdata/class/fail_init.carbon b/toolchain/check/testdata/class/fail_init.carbon
index b628bb84dd8d..669d67cb6933 100644
--- a/toolchain/check/testdata/class/fail_init.carbon
+++ b/toolchain/check/testdata/class/fail_init.carbon
@@ -35,7 +35,7 @@ fn F() {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Class, ()
+// CHECK:STDOUT:   %Class.decl = class_decl @Class, ()
 // CHECK:STDOUT:   %Class: type = class_type @Class
 // CHECK:STDOUT:   %F: <function> = fn_decl @F
 // CHECK:STDOUT: }
diff --git a/toolchain/check/testdata/class/fail_init_as_inplace.carbon b/toolchain/check/testdata/class/fail_init_as_inplace.carbon
index 0d4e197def2b..0a43201d8943 100644
--- a/toolchain/check/testdata/class/fail_init_as_inplace.carbon
+++ b/toolchain/check/testdata/class/fail_init_as_inplace.carbon
@@ -31,7 +31,7 @@ fn F() {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Class, ()
+// CHECK:STDOUT:   %Class.decl = class_decl @Class, ()
 // CHECK:STDOUT:   %Class: type = class_type @Class
 // CHECK:STDOUT:   %G: <function> = fn_decl @G
 // CHECK:STDOUT:   %F: <function> = fn_decl @F
diff --git a/toolchain/check/testdata/class/fail_memaccess_category.carbon b/toolchain/check/testdata/class/fail_memaccess_category.carbon
index 4e4a838c8b60..9a6b11f2e833 100644
--- a/toolchain/check/testdata/class/fail_memaccess_category.carbon
+++ b/toolchain/check/testdata/class/fail_memaccess_category.carbon
@@ -45,9 +45,9 @@ fn F(s: {.a: A}, b: B) {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @A, ()
+// CHECK:STDOUT:   %A.decl = class_decl @A, ()
 // CHECK:STDOUT:   %A: type = class_type @A
-// CHECK:STDOUT:   class_decl @B, ()
+// CHECK:STDOUT:   %B.decl = class_decl @B, ()
 // CHECK:STDOUT:   %B: type = class_type @B
 // CHECK:STDOUT:   %F: <function> = fn_decl @F.2
 // CHECK:STDOUT: }
diff --git a/toolchain/check/testdata/class/fail_member_of_let.carbon b/toolchain/check/testdata/class/fail_member_of_let.carbon
index e468ead20dcb..145a9000e120 100644
--- a/toolchain/check/testdata/class/fail_member_of_let.carbon
+++ b/toolchain/check/testdata/class/fail_member_of_let.carbon
@@ -28,7 +28,7 @@ fn T.F() {}
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Class, ()
+// CHECK:STDOUT:   %Class.decl = class_decl @Class, ()
 // CHECK:STDOUT:   %Class: type = class_type @Class
 // CHECK:STDOUT:   %Class.ref: type = name_ref Class, %Class
 // CHECK:STDOUT:   %T: type = bind_name T, %Class.ref
diff --git a/toolchain/check/testdata/class/fail_method.carbon b/toolchain/check/testdata/class/fail_method.carbon
index 587f05d4c954..4be3b5e2311a 100644
--- a/toolchain/check/testdata/class/fail_method.carbon
+++ b/toolchain/check/testdata/class/fail_method.carbon
@@ -39,7 +39,7 @@ fn F(c: Class) {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Class, ()
+// CHECK:STDOUT:   %Class.decl = class_decl @Class, ()
 // CHECK:STDOUT:   %Class: type = class_type @Class
 // CHECK:STDOUT:   %F: <function> = fn_decl @F
 // CHECK:STDOUT: }
diff --git a/toolchain/check/testdata/class/fail_redeclaration_introducer.carbon b/toolchain/check/testdata/class/fail_redeclaration_introducer.carbon
index b5dfbe662ee0..343855b9582b 100644
--- a/toolchain/check/testdata/class/fail_redeclaration_introducer.carbon
+++ b/toolchain/check/testdata/class/fail_redeclaration_introducer.carbon
@@ -81,28 +81,28 @@ base class G;
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @A, ()
+// CHECK:STDOUT:   %A.decl.loc7 = class_decl @A, ()
 // CHECK:STDOUT:   %A: type = class_type @A
-// CHECK:STDOUT:   class_decl @A, ()
-// CHECK:STDOUT:   class_decl @B, ()
+// CHECK:STDOUT:   %A.decl.loc14 = class_decl @A, ()
+// CHECK:STDOUT:   %B.decl.loc16 = class_decl @B, ()
 // CHECK:STDOUT:   %B: type = class_type @B
-// CHECK:STDOUT:   class_decl @B, ()
-// CHECK:STDOUT:   class_decl @C, ()
+// CHECK:STDOUT:   %B.decl.loc23 = class_decl @B, ()
+// CHECK:STDOUT:   %C.decl.loc25 = class_decl @C, ()
 // CHECK:STDOUT:   %C: type = class_type @C
-// CHECK:STDOUT:   class_decl @C, ()
-// CHECK:STDOUT:   class_decl @D, ()
+// CHECK:STDOUT:   %C.decl.loc32 = class_decl @C, ()
+// CHECK:STDOUT:   %D.decl.loc34 = class_decl @D, ()
 // CHECK:STDOUT:   %D: type = class_type @D
-// CHECK:STDOUT:   class_decl @D, ()
-// CHECK:STDOUT:   class_decl @E, ()
+// CHECK:STDOUT:   %D.decl.loc41 = class_decl @D, ()
+// CHECK:STDOUT:   %E.decl.loc43 = class_decl @E, ()
 // CHECK:STDOUT:   %E: type = class_type @E
-// CHECK:STDOUT:   class_decl @E, ()
-// CHECK:STDOUT:   class_decl @F, ()
+// CHECK:STDOUT:   %E.decl.loc50 = class_decl @E, ()
+// CHECK:STDOUT:   %F.decl.loc52 = class_decl @F, ()
 // CHECK:STDOUT:   %F: type = class_type @F
-// CHECK:STDOUT:   class_decl @F, ()
-// CHECK:STDOUT:   class_decl @G, ()
+// CHECK:STDOUT:   %F.decl.loc59 = class_decl @F, ()
+// CHECK:STDOUT:   %G.decl.loc61 = class_decl @G, ()
 // CHECK:STDOUT:   %G: type = class_type @G
-// CHECK:STDOUT:   class_decl @G, ()
-// CHECK:STDOUT:   class_decl @G, ()
+// CHECK:STDOUT:   %G.decl.loc68 = class_decl @G, ()
+// CHECK:STDOUT:   %G.decl.loc75 = class_decl @G, ()
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: class @A {
diff --git a/toolchain/check/testdata/class/fail_redeclaration_scope.carbon b/toolchain/check/testdata/class/fail_redeclaration_scope.carbon
index b810195afa00..23ced33e9a3e 100644
--- a/toolchain/check/testdata/class/fail_redeclaration_scope.carbon
+++ b/toolchain/check/testdata/class/fail_redeclaration_scope.carbon
@@ -28,38 +28,38 @@ class Y {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @A.1, ()
+// CHECK:STDOUT:   %A.decl.loc7 = class_decl @A.1, ()
 // CHECK:STDOUT:   %A: type = class_type @A.1
-// CHECK:STDOUT:   class_decl @X, ()
+// CHECK:STDOUT:   %X.decl = class_decl @X, ()
 // CHECK:STDOUT:   %X: type = class_type @X
-// CHECK:STDOUT:   class_decl @A.1, ()
-// CHECK:STDOUT:   class_decl @Y, ()
+// CHECK:STDOUT:   %A.decl.loc15 = class_decl @A.1, ()
+// CHECK:STDOUT:   %Y.decl = class_decl @Y, ()
 // CHECK:STDOUT:   %Y: type = class_type @Y
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: class @A.1 {
-// CHECK:STDOUT:   class_decl @B.2, ()
+// CHECK:STDOUT:   %B.decl = class_decl @B.2, ()
 // CHECK:STDOUT:   %B: type = class_type @B.2
 // CHECK:STDOUT:
 // CHECK:STDOUT: !members:
-// CHECK:STDOUT:   .B = <unexpected instref inst+11>
+// CHECK:STDOUT:   .B = %B.decl
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: class @X {
-// CHECK:STDOUT:   class_decl @A.2, ()
+// CHECK:STDOUT:   %A.decl = class_decl @A.2, ()
 // CHECK:STDOUT:   %A: type = class_type @A.2
-// CHECK:STDOUT:   class_decl @B.1, ()
+// CHECK:STDOUT:   %B.decl = class_decl @B.1, ()
 // CHECK:STDOUT:
 // CHECK:STDOUT: !members:
-// CHECK:STDOUT:   .A = <unexpected instref inst+4>
+// CHECK:STDOUT:   .A = %A.decl
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: class @A.2 {
-// CHECK:STDOUT:   class_decl @B.1, ()
+// CHECK:STDOUT:   %B.decl = class_decl @B.1, ()
 // CHECK:STDOUT:   %B: type = class_type @B.1
 // CHECK:STDOUT:
 // CHECK:STDOUT: !members:
-// CHECK:STDOUT:   .B = <unexpected instref inst+6>
+// CHECK:STDOUT:   .B = %B.decl
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: class @B.1 {
@@ -70,7 +70,7 @@ class Y {
 // CHECK:STDOUT: class @B.2;
 // CHECK:STDOUT:
 // CHECK:STDOUT: class @Y {
-// CHECK:STDOUT:   class_decl @.1, ()
+// CHECK:STDOUT:   %.decl = class_decl @.1, ()
 // CHECK:STDOUT:   %.loc21: type = class_type @.1
 // CHECK:STDOUT:
 // CHECK:STDOUT: !members:
diff --git a/toolchain/check/testdata/class/fail_redefinition.carbon b/toolchain/check/testdata/class/fail_redefinition.carbon
index a3ed259792dd..186332cc4751 100644
--- a/toolchain/check/testdata/class/fail_redefinition.carbon
+++ b/toolchain/check/testdata/class/fail_redefinition.carbon
@@ -31,9 +31,9 @@ fn Class.H() {}
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Class, ()
+// CHECK:STDOUT:   %Class.decl.loc7 = class_decl @Class, ()
 // CHECK:STDOUT:   %Class: type = class_type @Class
-// CHECK:STDOUT:   class_decl @Class, ()
+// CHECK:STDOUT:   %Class.decl.loc18 = class_decl @Class, ()
 // CHECK:STDOUT:   %F: <function> = fn_decl @F
 // CHECK:STDOUT:   %G: <function> = fn_decl @G
 // CHECK:STDOUT:   %H: <function> = fn_decl @H
diff --git a/toolchain/check/testdata/class/fail_reorder.carbon b/toolchain/check/testdata/class/fail_reorder.carbon
index 20705e7bcab4..9f61b5d373b4 100644
--- a/toolchain/check/testdata/class/fail_reorder.carbon
+++ b/toolchain/check/testdata/class/fail_reorder.carbon
@@ -32,7 +32,7 @@ class Class {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Class, ()
+// CHECK:STDOUT:   %Class.decl = class_decl @Class, ()
 // CHECK:STDOUT:   %Class: type = class_type @Class
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
diff --git a/toolchain/check/testdata/class/fail_scope.carbon b/toolchain/check/testdata/class/fail_scope.carbon
index fcb3c118e8f5..eb1590e6d1fd 100644
--- a/toolchain/check/testdata/class/fail_scope.carbon
+++ b/toolchain/check/testdata/class/fail_scope.carbon
@@ -24,7 +24,7 @@ fn G() -> i32 {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Class, ()
+// CHECK:STDOUT:   %Class.decl = class_decl @Class, ()
 // CHECK:STDOUT:   %Class: type = class_type @Class
 // CHECK:STDOUT:   %G: <function> = fn_decl @G
 // CHECK:STDOUT: }
diff --git a/toolchain/check/testdata/class/fail_self.carbon b/toolchain/check/testdata/class/fail_self.carbon
index 74ab187e02c3..2cf2928e50de 100644
--- a/toolchain/check/testdata/class/fail_self.carbon
+++ b/toolchain/check/testdata/class/fail_self.carbon
@@ -59,11 +59,11 @@ fn CallWrongSelf(ws: WrongSelf) {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Class, ()
+// CHECK:STDOUT:   %Class.decl = class_decl @Class, ()
 // CHECK:STDOUT:   %Class: type = class_type @Class
 // CHECK:STDOUT:   %F: <function> = fn_decl @F.1
 // CHECK:STDOUT:   %G: <function> = fn_decl @G
-// CHECK:STDOUT:   class_decl @WrongSelf, ()
+// CHECK:STDOUT:   %WrongSelf.decl = class_decl @WrongSelf, ()
 // CHECK:STDOUT:   %WrongSelf: type = class_type @WrongSelf
 // CHECK:STDOUT:   %CallWrongSelf: <function> = fn_decl @CallWrongSelf
 // CHECK:STDOUT: }
diff --git a/toolchain/check/testdata/class/fail_unbound_field.carbon b/toolchain/check/testdata/class/fail_unbound_field.carbon
index 1dec25b95e69..54fa2b9284f6 100644
--- a/toolchain/check/testdata/class/fail_unbound_field.carbon
+++ b/toolchain/check/testdata/class/fail_unbound_field.carbon
@@ -28,7 +28,7 @@ fn G() -> i32 {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Class, ()
+// CHECK:STDOUT:   %Class.decl = class_decl @Class, ()
 // CHECK:STDOUT:   %Class: type = class_type @Class
 // CHECK:STDOUT:   %G: <function> = fn_decl @G
 // CHECK:STDOUT: }
diff --git a/toolchain/check/testdata/class/fail_unknown_member.carbon b/toolchain/check/testdata/class/fail_unknown_member.carbon
index 1ee43d952d95..8ab5087ce4a8 100644
--- a/toolchain/check/testdata/class/fail_unknown_member.carbon
+++ b/toolchain/check/testdata/class/fail_unknown_member.carbon
@@ -24,7 +24,7 @@ fn G(c: Class) -> i32 {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Class, ()
+// CHECK:STDOUT:   %Class.decl = class_decl @Class, ()
 // CHECK:STDOUT:   %Class: type = class_type @Class
 // CHECK:STDOUT:   %G: <function> = fn_decl @G
 // CHECK:STDOUT: }
diff --git a/toolchain/check/testdata/class/field_access.carbon b/toolchain/check/testdata/class/field_access.carbon
index e7585824073c..71cccca80545 100644
--- a/toolchain/check/testdata/class/field_access.carbon
+++ b/toolchain/check/testdata/class/field_access.carbon
@@ -24,7 +24,7 @@ fn Run() -> i32 {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Class, ()
+// CHECK:STDOUT:   %Class.decl = class_decl @Class, ()
 // CHECK:STDOUT:   %Class: type = class_type @Class
 // CHECK:STDOUT:   %Run: <function> = fn_decl @Run
 // CHECK:STDOUT: }
diff --git a/toolchain/check/testdata/class/field_access_in_value.carbon b/toolchain/check/testdata/class/field_access_in_value.carbon
index 008992e2f239..a0fd97825174 100644
--- a/toolchain/check/testdata/class/field_access_in_value.carbon
+++ b/toolchain/check/testdata/class/field_access_in_value.carbon
@@ -25,7 +25,7 @@ fn Run() -> i32 {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Class, ()
+// CHECK:STDOUT:   %Class.decl = class_decl @Class, ()
 // CHECK:STDOUT:   %Class: type = class_type @Class
 // CHECK:STDOUT:   %Run: <function> = fn_decl @Run
 // CHECK:STDOUT: }
diff --git a/toolchain/check/testdata/class/forward_declared.carbon b/toolchain/check/testdata/class/forward_declared.carbon
index 21f0559cfd7a..f44853a28c6e 100644
--- a/toolchain/check/testdata/class/forward_declared.carbon
+++ b/toolchain/check/testdata/class/forward_declared.carbon
@@ -11,7 +11,7 @@ fn F(p: Class*) -> Class* { return p; }
 // CHECK:STDOUT: --- forward_declared.carbon
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Class, ()
+// CHECK:STDOUT:   %Class.decl = class_decl @Class, ()
 // CHECK:STDOUT:   %Class: type = class_type @Class
 // CHECK:STDOUT:   %F: <function> = fn_decl @F
 // CHECK:STDOUT: }
diff --git a/toolchain/check/testdata/class/init.carbon b/toolchain/check/testdata/class/init.carbon
index c04bfc0654d7..f03f76c51728 100644
--- a/toolchain/check/testdata/class/init.carbon
+++ b/toolchain/check/testdata/class/init.carbon
@@ -26,7 +26,7 @@ fn MakeReorder(n: i32, next: Class*) -> Class {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Class, ()
+// CHECK:STDOUT:   %Class.decl = class_decl @Class, ()
 // CHECK:STDOUT:   %Class: type = class_type @Class
 // CHECK:STDOUT:   %Make: <function> = fn_decl @Make
 // CHECK:STDOUT:   %MakeReorder: <function> = fn_decl @MakeReorder
diff --git a/toolchain/check/testdata/class/init_as.carbon b/toolchain/check/testdata/class/init_as.carbon
index c4bc96986868..f6b2ca20b0d6 100644
--- a/toolchain/check/testdata/class/init_as.carbon
+++ b/toolchain/check/testdata/class/init_as.carbon
@@ -21,7 +21,7 @@ fn F() -> i32 {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Class, ()
+// CHECK:STDOUT:   %Class.decl = class_decl @Class, ()
 // CHECK:STDOUT:   %Class: type = class_type @Class
 // CHECK:STDOUT:   %F: <function> = fn_decl @F
 // CHECK:STDOUT: }
diff --git a/toolchain/check/testdata/class/init_nested.carbon b/toolchain/check/testdata/class/init_nested.carbon
index 656b0eeb8b92..aed385303448 100644
--- a/toolchain/check/testdata/class/init_nested.carbon
+++ b/toolchain/check/testdata/class/init_nested.carbon
@@ -32,10 +32,10 @@ fn MakeOuter() -> Outer {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Inner, ()
+// CHECK:STDOUT:   %Inner.decl = class_decl @Inner, ()
 // CHECK:STDOUT:   %Inner: type = class_type @Inner
 // CHECK:STDOUT:   %MakeInner: <function> = fn_decl @MakeInner
-// CHECK:STDOUT:   class_decl @Outer, ()
+// CHECK:STDOUT:   %Outer.decl = class_decl @Outer, ()
 // CHECK:STDOUT:   %Outer: type = class_type @Outer
 // CHECK:STDOUT:   %MakeOuter: <function> = fn_decl @MakeOuter
 // CHECK:STDOUT: }
diff --git a/toolchain/check/testdata/class/method.carbon b/toolchain/check/testdata/class/method.carbon
index 4128b31358dc..76627d0e82c1 100644
--- a/toolchain/check/testdata/class/method.carbon
+++ b/toolchain/check/testdata/class/method.carbon
@@ -52,7 +52,7 @@ fn CallGOnInitializingExpr() -> i32 {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Class, ()
+// CHECK:STDOUT:   %Class.decl = class_decl @Class, ()
 // CHECK:STDOUT:   %Class: type = class_type @Class
 // CHECK:STDOUT:   %F: <function> = fn_decl @F
 // CHECK:STDOUT:   %Call: <function> = fn_decl @Call
diff --git a/toolchain/check/testdata/class/nested.carbon b/toolchain/check/testdata/class/nested.carbon
index 60016d8ea295..e7d229db450d 100644
--- a/toolchain/check/testdata/class/nested.carbon
+++ b/toolchain/check/testdata/class/nested.carbon
@@ -38,13 +38,13 @@ fn F(a: Outer*) {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Outer, ()
+// CHECK:STDOUT:   %Outer.decl = class_decl @Outer, ()
 // CHECK:STDOUT:   %Outer: type = class_type @Outer
 // CHECK:STDOUT:   %F: <function> = fn_decl @F
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: class @Outer {
-// CHECK:STDOUT:   class_decl @Inner, ()
+// CHECK:STDOUT:   %Inner.decl = class_decl @Inner, ()
 // CHECK:STDOUT:   %Inner: type = class_type @Inner
 // CHECK:STDOUT:   %Self.ref: type = name_ref Self, file.%Outer
 // CHECK:STDOUT:   %.loc14_15: type = ptr_type Outer
@@ -63,7 +63,7 @@ fn F(a: Outer*) {
 // CHECK:STDOUT:   %pi: <unbound field of class Outer> = bind_name pi, %.loc16_9.2
 // CHECK:STDOUT:
 // CHECK:STDOUT: !members:
-// CHECK:STDOUT:   .Inner = <unexpected instref inst+2>
+// CHECK:STDOUT:   .Inner = %Inner.decl
 // CHECK:STDOUT:   .po = %po
 // CHECK:STDOUT:   .qo = %qo
 // CHECK:STDOUT:   .pi = %pi
diff --git a/toolchain/check/testdata/class/nested_name.carbon b/toolchain/check/testdata/class/nested_name.carbon
index 8bc021e5365e..c093f169635a 100644
--- a/toolchain/check/testdata/class/nested_name.carbon
+++ b/toolchain/check/testdata/class/nested_name.carbon
@@ -29,18 +29,18 @@ fn G(o: Outer) {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Outer, ()
+// CHECK:STDOUT:   %Outer.decl = class_decl @Outer, ()
 // CHECK:STDOUT:   %Outer: type = class_type @Outer
 // CHECK:STDOUT:   %F: <function> = fn_decl @F
 // CHECK:STDOUT:   %G: <function> = fn_decl @G
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: class @Outer {
-// CHECK:STDOUT:   class_decl @Inner, ()
+// CHECK:STDOUT:   %Inner.decl = class_decl @Inner, ()
 // CHECK:STDOUT:   %Inner: type = class_type @Inner
 // CHECK:STDOUT:
 // CHECK:STDOUT: !members:
-// CHECK:STDOUT:   .Inner = <unexpected instref inst+2>
+// CHECK:STDOUT:   .Inner = %Inner.decl
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: class @Inner {
diff --git a/toolchain/check/testdata/class/raw_self.carbon b/toolchain/check/testdata/class/raw_self.carbon
index d2287b87605a..929e27216df8 100644
--- a/toolchain/check/testdata/class/raw_self.carbon
+++ b/toolchain/check/testdata/class/raw_self.carbon
@@ -29,7 +29,7 @@ fn Class.G[self: Class](r#self: i32) -> (i32, i32) {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Class, ()
+// CHECK:STDOUT:   %Class.decl = class_decl @Class, ()
 // CHECK:STDOUT:   %Class: type = class_type @Class
 // CHECK:STDOUT:   %F: <function> = fn_decl @F
 // CHECK:STDOUT:   %G: <function> = fn_decl @G
diff --git a/toolchain/check/testdata/class/raw_self_type.carbon b/toolchain/check/testdata/class/raw_self_type.carbon
index dd407d6896b4..c43dd980a1d9 100644
--- a/toolchain/check/testdata/class/raw_self_type.carbon
+++ b/toolchain/check/testdata/class/raw_self_type.carbon
@@ -18,7 +18,7 @@ class Class {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Class, ()
+// CHECK:STDOUT:   %Class.decl = class_decl @Class, ()
 // CHECK:STDOUT:   %Class: type = class_type @Class
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
diff --git a/toolchain/check/testdata/class/redeclaration.carbon b/toolchain/check/testdata/class/redeclaration.carbon
index 8eb71e33eb2e..7ff76843f616 100644
--- a/toolchain/check/testdata/class/redeclaration.carbon
+++ b/toolchain/check/testdata/class/redeclaration.carbon
@@ -19,9 +19,9 @@ fn Class.F() {}
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Class, ()
+// CHECK:STDOUT:   %Class.decl.loc7 = class_decl @Class, ()
 // CHECK:STDOUT:   %Class: type = class_type @Class
-// CHECK:STDOUT:   class_decl @Class, ()
+// CHECK:STDOUT:   %Class.decl.loc9 = class_decl @Class, ()
 // CHECK:STDOUT:   %F: <function> = fn_decl @F
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
diff --git a/toolchain/check/testdata/class/redeclaration_introducer.carbon b/toolchain/check/testdata/class/redeclaration_introducer.carbon
index ef58cfbf0c1a..0e11667bf344 100644
--- a/toolchain/check/testdata/class/redeclaration_introducer.carbon
+++ b/toolchain/check/testdata/class/redeclaration_introducer.carbon
@@ -19,15 +19,15 @@ abstract class C {}
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @A, ()
+// CHECK:STDOUT:   %A.decl.loc7 = class_decl @A, ()
 // CHECK:STDOUT:   %A: type = class_type @A
-// CHECK:STDOUT:   class_decl @B, ()
+// CHECK:STDOUT:   %B.decl.loc8 = class_decl @B, ()
 // CHECK:STDOUT:   %B: type = class_type @B
-// CHECK:STDOUT:   class_decl @C, ()
+// CHECK:STDOUT:   %C.decl.loc9 = class_decl @C, ()
 // CHECK:STDOUT:   %C: type = class_type @C
-// CHECK:STDOUT:   class_decl @A, ()
-// CHECK:STDOUT:   class_decl @B, ()
-// CHECK:STDOUT:   class_decl @C, ()
+// CHECK:STDOUT:   %A.decl.loc11 = class_decl @A, ()
+// CHECK:STDOUT:   %B.decl.loc12 = class_decl @B, ()
+// CHECK:STDOUT:   %C.decl.loc13 = class_decl @C, ()
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: class @A {
diff --git a/toolchain/check/testdata/class/reenter_scope.carbon b/toolchain/check/testdata/class/reenter_scope.carbon
index 6fab97837044..e9b10ed1d0fc 100644
--- a/toolchain/check/testdata/class/reenter_scope.carbon
+++ b/toolchain/check/testdata/class/reenter_scope.carbon
@@ -20,7 +20,7 @@ fn Class.F() -> i32 {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Class, ()
+// CHECK:STDOUT:   %Class.decl = class_decl @Class, ()
 // CHECK:STDOUT:   %Class: type = class_type @Class
 // CHECK:STDOUT:   %F: <function> = fn_decl @F
 // CHECK:STDOUT: }
diff --git a/toolchain/check/testdata/class/scope.carbon b/toolchain/check/testdata/class/scope.carbon
index a78d67e42f03..26da34a10225 100644
--- a/toolchain/check/testdata/class/scope.carbon
+++ b/toolchain/check/testdata/class/scope.carbon
@@ -29,7 +29,7 @@ fn Run() -> i32 {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Class, ()
+// CHECK:STDOUT:   %Class.decl = class_decl @Class, ()
 // CHECK:STDOUT:   %Class: type = class_type @Class
 // CHECK:STDOUT:   %F: <function> = fn_decl @F.2
 // CHECK:STDOUT:   %Run: <function> = fn_decl @Run
diff --git a/toolchain/check/testdata/class/self.carbon b/toolchain/check/testdata/class/self.carbon
index b921e820e821..60208f739b26 100644
--- a/toolchain/check/testdata/class/self.carbon
+++ b/toolchain/check/testdata/class/self.carbon
@@ -27,7 +27,7 @@ fn Class.G[addr self: Class*]() -> i32 {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Class, ()
+// CHECK:STDOUT:   %Class.decl = class_decl @Class, ()
 // CHECK:STDOUT:   %Class: type = class_type @Class
 // CHECK:STDOUT:   %F: <function> = fn_decl @F
 // CHECK:STDOUT:   %G: <function> = fn_decl @G
diff --git a/toolchain/check/testdata/class/self_type.carbon b/toolchain/check/testdata/class/self_type.carbon
index c8f6f837d3b8..309e80514fa7 100644
--- a/toolchain/check/testdata/class/self_type.carbon
+++ b/toolchain/check/testdata/class/self_type.carbon
@@ -24,7 +24,7 @@ fn Class.F[self: Class]() -> i32 {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Class, ()
+// CHECK:STDOUT:   %Class.decl = class_decl @Class, ()
 // CHECK:STDOUT:   %Class: type = class_type @Class
 // CHECK:STDOUT:   %F: <function> = fn_decl @F
 // CHECK:STDOUT: }
diff --git a/toolchain/check/testdata/class/static_method.carbon b/toolchain/check/testdata/class/static_method.carbon
index 3510992d0fff..7b59a4c2037f 100644
--- a/toolchain/check/testdata/class/static_method.carbon
+++ b/toolchain/check/testdata/class/static_method.carbon
@@ -22,7 +22,7 @@ fn Run() -> i32 {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Class, ()
+// CHECK:STDOUT:   %Class.decl = class_decl @Class, ()
 // CHECK:STDOUT:   %Class: type = class_type @Class
 // CHECK:STDOUT:   %Run: <function> = fn_decl @Run
 // CHECK:STDOUT: }
diff --git a/toolchain/check/testdata/if_expr/fail_not_in_function.carbon b/toolchain/check/testdata/if_expr/fail_not_in_function.carbon
index 10583cc9bb69..b9451f0d164b 100644
--- a/toolchain/check/testdata/if_expr/fail_not_in_function.carbon
+++ b/toolchain/check/testdata/if_expr/fail_not_in_function.carbon
@@ -42,7 +42,7 @@ class C {
 // CHECK:STDOUT: file {
 // CHECK:STDOUT:   %.loc17: i32 = block_arg <unexpected instblockref block4>
 // CHECK:STDOUT:   %x: i32 = bind_name x, %.loc17
-// CHECK:STDOUT:   class_decl @C, ()
+// CHECK:STDOUT:   %C.decl = class_decl @C, ()
 // CHECK:STDOUT:   %C: type = class_type @C
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
diff --git a/toolchain/check/testdata/return/fail_return_with_returned_var.carbon b/toolchain/check/testdata/return/fail_return_with_returned_var.carbon
index 1760d1af0ef9..62d9bd756d3a 100644
--- a/toolchain/check/testdata/return/fail_return_with_returned_var.carbon
+++ b/toolchain/check/testdata/return/fail_return_with_returned_var.carbon
@@ -36,7 +36,7 @@ fn G() -> C {
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
 // CHECK:STDOUT:   %F: <function> = fn_decl @F
-// CHECK:STDOUT:   class_decl @C, ()
+// CHECK:STDOUT:   %C.decl = class_decl @C, ()
 // CHECK:STDOUT:   %C: type = class_type @C
 // CHECK:STDOUT:   %G: <function> = fn_decl @G
 // CHECK:STDOUT: }
diff --git a/toolchain/check/testdata/return/returned_var.carbon b/toolchain/check/testdata/return/returned_var.carbon
index 95c2ebc252d9..b768f24d0603 100644
--- a/toolchain/check/testdata/return/returned_var.carbon
+++ b/toolchain/check/testdata/return/returned_var.carbon
@@ -27,7 +27,7 @@ fn G() -> i32 {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @C, ()
+// CHECK:STDOUT:   %C.decl = class_decl @C, ()
 // CHECK:STDOUT:   %C: type = class_type @C
 // CHECK:STDOUT:   %F: <function> = fn_decl @F
 // CHECK:STDOUT:   %G: <function> = fn_decl @G
diff --git a/toolchain/check/testdata/struct/fail_nested_incomplete.carbon b/toolchain/check/testdata/struct/fail_nested_incomplete.carbon
index 39982d8e4915..b5a0a79b9fd1 100644
--- a/toolchain/check/testdata/struct/fail_nested_incomplete.carbon
+++ b/toolchain/check/testdata/struct/fail_nested_incomplete.carbon
@@ -26,7 +26,7 @@ var p: Incomplete* = &s.a;
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Incomplete, ()
+// CHECK:STDOUT:   %Incomplete.decl = class_decl @Incomplete, ()
 // CHECK:STDOUT:   %Incomplete: type = class_type @Incomplete
 // CHECK:STDOUT:   %Incomplete.ref.loc15: type = name_ref Incomplete, %Incomplete
 // CHECK:STDOUT:   %.loc15: type = struct_type {.a: Incomplete}
diff --git a/toolchain/check/testdata/tuples/fail_nested_incomplete.carbon b/toolchain/check/testdata/tuples/fail_nested_incomplete.carbon
index 0580411ba94a..8e03c5206f05 100644
--- a/toolchain/check/testdata/tuples/fail_nested_incomplete.carbon
+++ b/toolchain/check/testdata/tuples/fail_nested_incomplete.carbon
@@ -28,7 +28,7 @@ var p: Incomplete* = &t[1];
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @Incomplete, ()
+// CHECK:STDOUT:   %Incomplete.decl = class_decl @Incomplete, ()
 // CHECK:STDOUT:   %Incomplete: type = class_type @Incomplete
 // CHECK:STDOUT:   %Incomplete.ref.loc15: type = name_ref Incomplete, %Incomplete
 // CHECK:STDOUT:   %.loc15_24.1: (type, type) = tuple_literal (i32, %Incomplete.ref.loc15)
diff --git a/toolchain/check/testdata/var/fail_not_copyable.carbon b/toolchain/check/testdata/var/fail_not_copyable.carbon
index 7121c6ded818..341eea270666 100644
--- a/toolchain/check/testdata/var/fail_not_copyable.carbon
+++ b/toolchain/check/testdata/var/fail_not_copyable.carbon
@@ -32,7 +32,7 @@ fn F(x: X) {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
-// CHECK:STDOUT:   class_decl @X, ()
+// CHECK:STDOUT:   %X.decl = class_decl @X, ()
 // CHECK:STDOUT:   %X: type = class_type @X
 // CHECK:STDOUT:   %F: <function> = fn_decl @F
 // CHECK:STDOUT: }
diff --git a/toolchain/sem_ir/formatter.cpp b/toolchain/sem_ir/formatter.cpp
index 87aeffe15ea6..ba53b5a44d33 100644
--- a/toolchain/sem_ir/formatter.cpp
+++ b/toolchain/sem_ir/formatter.cpp
@@ -437,6 +437,12 @@ class InstNamer {
                                .name_id);
           continue;
         }
+        case ClassDecl::Kind: {
+          add_inst_name_id(
+              sem_ir_.classes().Get(inst.As<ClassDecl>().class_id).name_id,
+              ".decl");
+          continue;
+        }
         case ClassType::Kind: {
           add_inst_name_id(
               sem_ir_.classes().Get(inst.As<ClassType>().class_id).name_id);
@@ -710,6 +716,12 @@ class Formatter {
     }
   }
 
+  // Print ClassDecl with type-like semantics even though it lacks a type_id.
+  auto FormatInstructionLHS(InstId inst_id, ClassDecl /*inst*/) -> void {
+    FormatInstName(inst_id);
+    out_ << " = ";
+  }
+
   template <typename InstT>
   auto FormatInstructionRHS(InstT inst) -> void {
     // By default, an instruction has a comma-separated argument list.