Use the package/library name in ImportIRId formatting. (#4154)

Also adds import_ir_scope to namespace formatting. I'd done this as an
aid for #4153, and am splitting it out.

---------

Co-authored-by: Geoff Romer <gromer@google.com>

toolchain/check/testdata/function/declaration/fail_param_in_type.carbon

@@ -24,8 +24,8 @@ fn F(n: i32, a: [i32; n]*);
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref.1: %Int32.type = import_ref ir3, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.2: %Int32.type = import_ref ir3, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.1: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.2: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
@@ -34,7 +34,15 @@ fn F(n: i32, a: [i32; n]*);
 // CHECK:STDOUT:     .F = %F.decl
 // CHECK:STDOUT:   }
 // CHECK:STDOUT:   %Core.import = import Core
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {}
+// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT:     import Core//prelude
+// CHECK:STDOUT:     import Core//prelude/operators
+// CHECK:STDOUT:     import Core//prelude/types
+// CHECK:STDOUT:     import Core//prelude/operators/arithmetic
+// CHECK:STDOUT:     import Core//prelude/operators/bitwise
+// CHECK:STDOUT:     import Core//prelude/operators/comparison
+// CHECK:STDOUT:     import Core//prelude/types/bool
+// CHECK:STDOUT:   }
 // CHECK:STDOUT:   %F.decl: %F.type = fn_decl @F [template = constants.%F] {
 // CHECK:STDOUT:     %int.make_type_32.loc14_9: init type = call constants.%Int32() [template = i32]
 // CHECK:STDOUT:     %.loc14_9.1: type = value_of_initializer %int.make_type_32.loc14_9 [template = i32]

toolchain/check/testdata/function/declaration/fail_param_redecl.carbon

@@ -27,8 +27,8 @@ fn F(n: i32, n: i32);
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref.1: %Int32.type = import_ref ir3, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.2: %Int32.type = import_ref ir3, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.1: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.2: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
@@ -37,7 +37,15 @@ fn F(n: i32, n: i32);
 // CHECK:STDOUT:     .F = %F.decl
 // CHECK:STDOUT:   }
 // CHECK:STDOUT:   %Core.import = import Core
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {}
+// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT:     import Core//prelude
+// CHECK:STDOUT:     import Core//prelude/operators
+// CHECK:STDOUT:     import Core//prelude/types
+// CHECK:STDOUT:     import Core//prelude/operators/arithmetic
+// CHECK:STDOUT:     import Core//prelude/operators/bitwise
+// CHECK:STDOUT:     import Core//prelude/operators/comparison
+// CHECK:STDOUT:     import Core//prelude/types/bool
+// CHECK:STDOUT:   }
 // CHECK:STDOUT:   %F.decl: %F.type = fn_decl @F [template = constants.%F] {
 // CHECK:STDOUT:     %int.make_type_32.loc17_9: init type = call constants.%Int32() [template = i32]
 // CHECK:STDOUT:     %.loc17_9.1: type = value_of_initializer %int.make_type_32.loc17_9 [template = i32]

toolchain/check/testdata/function/declaration/import.carbon

@@ -389,10 +389,10 @@ import library "extern_api";
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref.1: %Int32.type = import_ref ir3, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.2: %Int32.type = import_ref ir3, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.3: %Int32.type = import_ref ir3, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.4: %Int32.type = import_ref ir3, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.1: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.2: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.3: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.4: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
@@ -405,7 +405,15 @@ import library "extern_api";
 // CHECK:STDOUT:     .NS = %NS
 // CHECK:STDOUT:   }
 // CHECK:STDOUT:   %Core.import = import Core
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {}
+// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT:     import Core//prelude
+// CHECK:STDOUT:     import Core//prelude/operators
+// CHECK:STDOUT:     import Core//prelude/types
+// CHECK:STDOUT:     import Core//prelude/operators/arithmetic
+// CHECK:STDOUT:     import Core//prelude/operators/bitwise
+// CHECK:STDOUT:     import Core//prelude/operators/comparison
+// CHECK:STDOUT:     import Core//prelude/types/bool
+// CHECK:STDOUT:   }
 // CHECK:STDOUT:   %A.decl: %A.type = fn_decl @A [template = constants.%A] {}
 // CHECK:STDOUT:   %B.decl: %B.type = fn_decl @B [template = constants.%B] {
 // CHECK:STDOUT:     %int.make_type_32.loc5_9: init type = call constants.%Int32() [template = i32]
@@ -473,10 +481,10 @@ import library "extern_api";
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref.1: %Int32.type = import_ref ir3, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.2: %Int32.type = import_ref ir3, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.3: %Int32.type = import_ref ir3, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.4: %Int32.type = import_ref ir3, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.1: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.2: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.3: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.4: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
@@ -489,7 +497,15 @@ import library "extern_api";
 // CHECK:STDOUT:     .NS = %NS
 // CHECK:STDOUT:   }
 // CHECK:STDOUT:   %Core.import = import Core
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {}
+// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT:     import Core//prelude
+// CHECK:STDOUT:     import Core//prelude/operators
+// CHECK:STDOUT:     import Core//prelude/types
+// CHECK:STDOUT:     import Core//prelude/operators/arithmetic
+// CHECK:STDOUT:     import Core//prelude/operators/bitwise
+// CHECK:STDOUT:     import Core//prelude/operators/comparison
+// CHECK:STDOUT:     import Core//prelude/types/bool
+// CHECK:STDOUT:   }
 // CHECK:STDOUT:   %A.decl: %A.type = fn_decl @A [template = constants.%A] {}
 // CHECK:STDOUT:   %B.decl: %B.type = fn_decl @B [template = constants.%B] {
 // CHECK:STDOUT:     %int.make_type_32.loc5_16: init type = call constants.%Int32() [template = i32]
@@ -558,13 +574,13 @@ import library "extern_api";
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref.1: %A.type = import_ref ir1, inst+3, loaded [template = constants.%A]
-// CHECK:STDOUT:   %import_ref.2: %B.type = import_ref ir1, inst+22, loaded [template = constants.%B]
-// CHECK:STDOUT:   %import_ref.3: %C.type = import_ref ir1, inst+44, loaded [template = constants.%C]
-// CHECK:STDOUT:   %import_ref.4: %D.type = import_ref ir1, inst+47, loaded [template = constants.%D]
-// CHECK:STDOUT:   %import_ref.5: %E.type = import_ref ir1, inst+51, loaded [template = constants.%E]
-// CHECK:STDOUT:   %import_ref.6: %Int32.type = import_ref ir4, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.7: %Int32.type = import_ref ir4, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.1: %A.type = import_ref Main//api, inst+3, loaded [template = constants.%A]
+// CHECK:STDOUT:   %import_ref.2: %B.type = import_ref Main//api, inst+22, loaded [template = constants.%B]
+// CHECK:STDOUT:   %import_ref.3: %C.type = import_ref Main//api, inst+44, loaded [template = constants.%C]
+// CHECK:STDOUT:   %import_ref.4: %D.type = import_ref Main//api, inst+47, loaded [template = constants.%D]
+// CHECK:STDOUT:   %import_ref.5: %E.type = import_ref Main//api, inst+51, loaded [template = constants.%E]
+// CHECK:STDOUT:   %import_ref.6: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.7: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
@@ -583,11 +599,19 @@ import library "extern_api";
 // CHECK:STDOUT:   }
 // CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %default.import = import <invalid>
-// CHECK:STDOUT:   %import_ref: <namespace> = import_ref ir1, inst+50, loaded
+// CHECK:STDOUT:   %import_ref: <namespace> = import_ref Main//api, inst+50, loaded
 // CHECK:STDOUT:   %NS: <namespace> = namespace %import_ref, [template] {
 // CHECK:STDOUT:     .E = imports.%import_ref.5
 // CHECK:STDOUT:   }
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {}
+// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT:     import Core//prelude
+// CHECK:STDOUT:     import Core//prelude/operators
+// CHECK:STDOUT:     import Core//prelude/types
+// CHECK:STDOUT:     import Core//prelude/operators/arithmetic
+// CHECK:STDOUT:     import Core//prelude/operators/bitwise
+// CHECK:STDOUT:     import Core//prelude/operators/comparison
+// CHECK:STDOUT:     import Core//prelude/types/bool
+// CHECK:STDOUT:   }
 // CHECK:STDOUT:   %.loc6_9.1: %.1 = tuple_literal ()
 // CHECK:STDOUT:   %.loc6_9.2: type = converted %.loc6_9.1, constants.%.1 [template = constants.%.1]
 // CHECK:STDOUT:   %a.var: ref %.1 = var a
@@ -675,17 +699,17 @@ import library "extern_api";
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref.1: %A.type = import_ref ir1, inst+3, loaded [template = constants.%A]
-// CHECK:STDOUT:   %import_ref.2: %B.type = import_ref ir1, inst+22, loaded [template = constants.%B]
-// CHECK:STDOUT:   %import_ref.3: %C.type = import_ref ir1, inst+44, loaded [template = constants.%C]
-// CHECK:STDOUT:   %import_ref.4: %D.type = import_ref ir1, inst+47, loaded [template = constants.%D]
-// CHECK:STDOUT:   %import_ref.5: %E.type = import_ref ir1, inst+51, loaded [template = constants.%E]
-// CHECK:STDOUT:   %import_ref.6: %Int32.type = import_ref ir4, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.7: %Int32.type = import_ref ir4, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.8: %Int32.type = import_ref ir4, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.9: %Int32.type = import_ref ir4, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.10: %Int32.type = import_ref ir4, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.11: %Int32.type = import_ref ir4, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.1: %A.type = import_ref Main//api, inst+3, loaded [template = constants.%A]
+// CHECK:STDOUT:   %import_ref.2: %B.type = import_ref Main//api, inst+22, loaded [template = constants.%B]
+// CHECK:STDOUT:   %import_ref.3: %C.type = import_ref Main//api, inst+44, loaded [template = constants.%C]
+// CHECK:STDOUT:   %import_ref.4: %D.type = import_ref Main//api, inst+47, loaded [template = constants.%D]
+// CHECK:STDOUT:   %import_ref.5: %E.type = import_ref Main//api, inst+51, loaded [template = constants.%E]
+// CHECK:STDOUT:   %import_ref.6: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.7: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.8: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.9: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.10: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.11: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
@@ -704,11 +728,19 @@ import library "extern_api";
 // CHECK:STDOUT:   }
 // CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %default.import = import <invalid>
-// CHECK:STDOUT:   %import_ref: <namespace> = import_ref ir1, inst+50, loaded
+// CHECK:STDOUT:   %import_ref: <namespace> = import_ref Main//api, inst+50, loaded
 // CHECK:STDOUT:   %NS: <namespace> = namespace %import_ref, [template] {
 // CHECK:STDOUT:     .E = %E.decl
 // CHECK:STDOUT:   }
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {}
+// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT:     import Core//prelude
+// CHECK:STDOUT:     import Core//prelude/operators
+// CHECK:STDOUT:     import Core//prelude/types
+// CHECK:STDOUT:     import Core//prelude/operators/arithmetic
+// CHECK:STDOUT:     import Core//prelude/operators/bitwise
+// CHECK:STDOUT:     import Core//prelude/operators/comparison
+// CHECK:STDOUT:     import Core//prelude/types/bool
+// CHECK:STDOUT:   }
 // CHECK:STDOUT:   %A.decl: %A.type = fn_decl @A [template = constants.%A] {}
 // CHECK:STDOUT:   %B.decl: %B.type = fn_decl @B [template = constants.%B] {
 // CHECK:STDOUT:     %int.make_type_32.loc7_16: init type = call constants.%Int32() [template = i32]
@@ -824,17 +856,17 @@ import library "extern_api";
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref.1: %A.type = import_ref ir1, inst+3, loaded [template = constants.%A]
-// CHECK:STDOUT:   %import_ref.2: %B.type = import_ref ir1, inst+22, loaded [template = constants.%B]
-// CHECK:STDOUT:   %import_ref.3: %C.type = import_ref ir1, inst+44, loaded [template = constants.%C]
-// CHECK:STDOUT:   %import_ref.4: %D.type = import_ref ir1, inst+47, loaded [template = constants.%D]
-// CHECK:STDOUT:   %import_ref.5: %E.type = import_ref ir1, inst+51, loaded [template = constants.%E]
-// CHECK:STDOUT:   %import_ref.6: %Int32.type = import_ref ir4, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.7: %Int32.type = import_ref ir4, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.8: %Int32.type = import_ref ir4, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.9: %Int32.type = import_ref ir4, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.10: %Int32.type = import_ref ir4, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.11: %Int32.type = import_ref ir4, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.1: %A.type = import_ref Main//extern_api, inst+3, loaded [template = constants.%A]
+// CHECK:STDOUT:   %import_ref.2: %B.type = import_ref Main//extern_api, inst+22, loaded [template = constants.%B]
+// CHECK:STDOUT:   %import_ref.3: %C.type = import_ref Main//extern_api, inst+44, loaded [template = constants.%C]
+// CHECK:STDOUT:   %import_ref.4: %D.type = import_ref Main//extern_api, inst+47, loaded [template = constants.%D]
+// CHECK:STDOUT:   %import_ref.5: %E.type = import_ref Main//extern_api, inst+51, loaded [template = constants.%E]
+// CHECK:STDOUT:   %import_ref.6: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.7: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.8: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.9: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.10: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.11: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
@@ -853,11 +885,19 @@ import library "extern_api";
 // CHECK:STDOUT:   }
 // CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %default.import = import <invalid>
-// CHECK:STDOUT:   %import_ref: <namespace> = import_ref ir1, inst+50, loaded
+// CHECK:STDOUT:   %import_ref: <namespace> = import_ref Main//extern_api, inst+50, loaded
 // CHECK:STDOUT:   %NS: <namespace> = namespace %import_ref, [template] {
 // CHECK:STDOUT:     .E = %E.decl
 // CHECK:STDOUT:   }
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {}
+// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT:     import Core//prelude
+// CHECK:STDOUT:     import Core//prelude/operators
+// CHECK:STDOUT:     import Core//prelude/types
+// CHECK:STDOUT:     import Core//prelude/operators/arithmetic
+// CHECK:STDOUT:     import Core//prelude/operators/bitwise
+// CHECK:STDOUT:     import Core//prelude/operators/comparison
+// CHECK:STDOUT:     import Core//prelude/types/bool
+// CHECK:STDOUT:   }
 // CHECK:STDOUT:   %A.decl: %A.type = fn_decl @A [template = constants.%A] {}
 // CHECK:STDOUT:   %B.decl: %B.type = fn_decl @B [template = constants.%B] {
 // CHECK:STDOUT:     %int.make_type_32.loc7_16: init type = call constants.%Int32() [template = i32]
@@ -972,18 +1012,18 @@ import library "extern_api";
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref.1: %A.type = import_ref ir1, inst+3, loaded [template = constants.%A]
-// CHECK:STDOUT:   %import_ref.2: %B.type = import_ref ir1, inst+22, loaded [template = constants.%B]
-// CHECK:STDOUT:   %import_ref.3: %C.type = import_ref ir1, inst+44, loaded [template = constants.%C]
-// CHECK:STDOUT:   %import_ref.4: %D.type = import_ref ir1, inst+47, loaded [template = constants.%D]
-// CHECK:STDOUT:   %import_ref.5: %E.type = import_ref ir1, inst+51, loaded [template = constants.%E]
-// CHECK:STDOUT:   %import_ref.6 = import_ref ir2, inst+3, unloaded
-// CHECK:STDOUT:   %import_ref.7 = import_ref ir2, inst+22, unloaded
-// CHECK:STDOUT:   %import_ref.8 = import_ref ir2, inst+44, unloaded
-// CHECK:STDOUT:   %import_ref.9 = import_ref ir2, inst+47, unloaded
-// CHECK:STDOUT:   %import_ref.10 = import_ref ir2, inst+51, unloaded
-// CHECK:STDOUT:   %import_ref.11: %Int32.type = import_ref ir5, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.12: %Int32.type = import_ref ir5, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.1: %A.type = import_ref Main//api, inst+3, loaded [template = constants.%A]
+// CHECK:STDOUT:   %import_ref.2: %B.type = import_ref Main//api, inst+22, loaded [template = constants.%B]
+// CHECK:STDOUT:   %import_ref.3: %C.type = import_ref Main//api, inst+44, loaded [template = constants.%C]
+// CHECK:STDOUT:   %import_ref.4: %D.type = import_ref Main//api, inst+47, loaded [template = constants.%D]
+// CHECK:STDOUT:   %import_ref.5: %E.type = import_ref Main//api, inst+51, loaded [template = constants.%E]
+// CHECK:STDOUT:   %import_ref.6 = import_ref Main//extern_api, inst+3, unloaded
+// CHECK:STDOUT:   %import_ref.7 = import_ref Main//extern_api, inst+22, unloaded
+// CHECK:STDOUT:   %import_ref.8 = import_ref Main//extern_api, inst+44, unloaded
+// CHECK:STDOUT:   %import_ref.9 = import_ref Main//extern_api, inst+47, unloaded
+// CHECK:STDOUT:   %import_ref.10 = import_ref Main//extern_api, inst+51, unloaded
+// CHECK:STDOUT:   %import_ref.11: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.12: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
@@ -1002,11 +1042,19 @@ import library "extern_api";
 // CHECK:STDOUT:   }
 // CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %default.import = import <invalid>
-// CHECK:STDOUT:   %import_ref: <namespace> = import_ref ir1, inst+50, loaded
+// CHECK:STDOUT:   %import_ref: <namespace> = import_ref Main//api, inst+50, loaded
 // CHECK:STDOUT:   %NS: <namespace> = namespace %import_ref, [template] {
 // CHECK:STDOUT:     .E = imports.%import_ref.5
 // CHECK:STDOUT:   }
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {}
+// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT:     import Core//prelude
+// CHECK:STDOUT:     import Core//prelude/operators
+// CHECK:STDOUT:     import Core//prelude/types
+// CHECK:STDOUT:     import Core//prelude/operators/arithmetic
+// CHECK:STDOUT:     import Core//prelude/operators/bitwise
+// CHECK:STDOUT:     import Core//prelude/operators/comparison
+// CHECK:STDOUT:     import Core//prelude/types/bool
+// CHECK:STDOUT:   }
 // CHECK:STDOUT:   %.loc72_9.1: %.1 = tuple_literal ()
 // CHECK:STDOUT:   %.loc72_9.2: type = converted %.loc72_9.1, constants.%.1 [template = constants.%.1]
 // CHECK:STDOUT:   %a.var: ref %.1 = var a
@@ -1093,18 +1141,18 @@ import library "extern_api";
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref.1: %A.type = import_ref ir1, inst+3, loaded [template = constants.%A]
-// CHECK:STDOUT:   %import_ref.2: %B.type = import_ref ir1, inst+22, loaded [template = constants.%B]
-// CHECK:STDOUT:   %import_ref.3: %C.type = import_ref ir1, inst+44, loaded [template = constants.%C]
-// CHECK:STDOUT:   %import_ref.4: %D.type = import_ref ir1, inst+47, loaded [template = constants.%D]
-// CHECK:STDOUT:   %import_ref.5: %E.type = import_ref ir1, inst+51, loaded [template = constants.%E]
-// CHECK:STDOUT:   %import_ref.6 = import_ref ir2, inst+3, unloaded
-// CHECK:STDOUT:   %import_ref.7 = import_ref ir2, inst+22, unloaded
-// CHECK:STDOUT:   %import_ref.8 = import_ref ir2, inst+44, unloaded
-// CHECK:STDOUT:   %import_ref.9 = import_ref ir2, inst+47, unloaded
-// CHECK:STDOUT:   %import_ref.10 = import_ref ir2, inst+51, unloaded
-// CHECK:STDOUT:   %import_ref.11: %Int32.type = import_ref ir5, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.12: %Int32.type = import_ref ir5, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.1: %A.type = import_ref Main//extern_api, inst+3, loaded [template = constants.%A]
+// CHECK:STDOUT:   %import_ref.2: %B.type = import_ref Main//extern_api, inst+22, loaded [template = constants.%B]
+// CHECK:STDOUT:   %import_ref.3: %C.type = import_ref Main//extern_api, inst+44, loaded [template = constants.%C]
+// CHECK:STDOUT:   %import_ref.4: %D.type = import_ref Main//extern_api, inst+47, loaded [template = constants.%D]
+// CHECK:STDOUT:   %import_ref.5: %E.type = import_ref Main//extern_api, inst+51, loaded [template = constants.%E]
+// CHECK:STDOUT:   %import_ref.6 = import_ref Main//api, inst+3, unloaded
+// CHECK:STDOUT:   %import_ref.7 = import_ref Main//api, inst+22, unloaded
+// CHECK:STDOUT:   %import_ref.8 = import_ref Main//api, inst+44, unloaded
+// CHECK:STDOUT:   %import_ref.9 = import_ref Main//api, inst+47, unloaded
+// CHECK:STDOUT:   %import_ref.10 = import_ref Main//api, inst+51, unloaded
+// CHECK:STDOUT:   %import_ref.11: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.12: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
@@ -1123,11 +1171,19 @@ import library "extern_api";
 // CHECK:STDOUT:   }
 // CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %default.import = import <invalid>
-// CHECK:STDOUT:   %import_ref: <namespace> = import_ref ir1, inst+50, loaded
+// CHECK:STDOUT:   %import_ref: <namespace> = import_ref Main//extern_api, inst+50, loaded
 // CHECK:STDOUT:   %NS: <namespace> = namespace %import_ref, [template] {
 // CHECK:STDOUT:     .E = imports.%import_ref.5
 // CHECK:STDOUT:   }
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {}
+// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT:     import Core//prelude
+// CHECK:STDOUT:     import Core//prelude/operators
+// CHECK:STDOUT:     import Core//prelude/types
+// CHECK:STDOUT:     import Core//prelude/operators/arithmetic
+// CHECK:STDOUT:     import Core//prelude/operators/bitwise
+// CHECK:STDOUT:     import Core//prelude/operators/comparison
+// CHECK:STDOUT:     import Core//prelude/types/bool
+// CHECK:STDOUT:   }
 // CHECK:STDOUT:   %.loc72_9.1: %.1 = tuple_literal ()
 // CHECK:STDOUT:   %.loc72_9.2: type = converted %.loc72_9.1, constants.%.1 [template = constants.%.1]
 // CHECK:STDOUT:   %a.var: ref %.1 = var a
@@ -1200,11 +1256,11 @@ import library "extern_api";
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref.1: %A.type = import_ref ir1, inst+3, loaded [template = constants.%A]
-// CHECK:STDOUT:   %import_ref.2 = import_ref ir1, inst+22, unloaded
-// CHECK:STDOUT:   %import_ref.3 = import_ref ir1, inst+44, unloaded
-// CHECK:STDOUT:   %import_ref.4 = import_ref ir1, inst+47, unloaded
-// CHECK:STDOUT:   %import_ref.5 = import_ref ir1, inst+51, unloaded
+// CHECK:STDOUT:   %import_ref.1: %A.type = import_ref Main//extern_api, inst+3, loaded [template = constants.%A]
+// CHECK:STDOUT:   %import_ref.2 = import_ref Main//extern_api, inst+22, unloaded
+// CHECK:STDOUT:   %import_ref.3 = import_ref Main//extern_api, inst+44, unloaded
+// CHECK:STDOUT:   %import_ref.4 = import_ref Main//extern_api, inst+47, unloaded
+// CHECK:STDOUT:   %import_ref.5 = import_ref Main//extern_api, inst+51, unloaded
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
@@ -1219,11 +1275,19 @@ import library "extern_api";
 // CHECK:STDOUT:   }
 // CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %default.import = import <invalid>
-// CHECK:STDOUT:   %import_ref: <namespace> = import_ref ir1, inst+50, loaded
+// CHECK:STDOUT:   %import_ref: <namespace> = import_ref Main//extern_api, inst+50, loaded
 // CHECK:STDOUT:   %NS: <namespace> = namespace %import_ref, [template] {
 // CHECK:STDOUT:     .E = imports.%import_ref.5
 // CHECK:STDOUT:   }
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {}
+// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT:     import Core//prelude
+// CHECK:STDOUT:     import Core//prelude/operators
+// CHECK:STDOUT:     import Core//prelude/types
+// CHECK:STDOUT:     import Core//prelude/operators/arithmetic
+// CHECK:STDOUT:     import Core//prelude/operators/bitwise
+// CHECK:STDOUT:     import Core//prelude/operators/comparison
+// CHECK:STDOUT:     import Core//prelude/types/bool
+// CHECK:STDOUT:   }
 // CHECK:STDOUT:   %.loc6_9.1: %.1 = tuple_literal ()
 // CHECK:STDOUT:   %.loc6_9.2: type = converted %.loc6_9.1, constants.%.1 [template = constants.%.1]
 // CHECK:STDOUT:   %a.var: ref %.1 = var a
@@ -1254,12 +1318,12 @@ import library "extern_api";
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref.1: %A.type = import_ref ir1, inst+3, loaded [template = constants.%A]
-// CHECK:STDOUT:   %import_ref.2 = import_ref ir1, inst+22, unloaded
-// CHECK:STDOUT:   %import_ref.3 = import_ref ir1, inst+44, unloaded
-// CHECK:STDOUT:   %import_ref.4 = import_ref ir1, inst+47, unloaded
-// CHECK:STDOUT:   %import_ref.5 = import_ref ir1, inst+51, unloaded
-// CHECK:STDOUT:   %import_ref.6: %Int32.type = import_ref ir4, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.1: %A.type = import_ref Main//extern_api, inst+3, loaded [template = constants.%A]
+// CHECK:STDOUT:   %import_ref.2 = import_ref Main//extern_api, inst+22, unloaded
+// CHECK:STDOUT:   %import_ref.3 = import_ref Main//extern_api, inst+44, unloaded
+// CHECK:STDOUT:   %import_ref.4 = import_ref Main//extern_api, inst+47, unloaded
+// CHECK:STDOUT:   %import_ref.5 = import_ref Main//extern_api, inst+51, unloaded
+// CHECK:STDOUT:   %import_ref.6: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
@@ -1274,11 +1338,19 @@ import library "extern_api";
 // CHECK:STDOUT:   }
 // CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %default.import = import <invalid>
-// CHECK:STDOUT:   %import_ref: <namespace> = import_ref ir1, inst+50, loaded
+// CHECK:STDOUT:   %import_ref: <namespace> = import_ref Main//extern_api, inst+50, loaded
 // CHECK:STDOUT:   %NS: <namespace> = namespace %import_ref, [template] {
 // CHECK:STDOUT:     .E = imports.%import_ref.5
 // CHECK:STDOUT:   }
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {}
+// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT:     import Core//prelude
+// CHECK:STDOUT:     import Core//prelude/operators
+// CHECK:STDOUT:     import Core//prelude/types
+// CHECK:STDOUT:     import Core//prelude/operators/arithmetic
+// CHECK:STDOUT:     import Core//prelude/operators/bitwise
+// CHECK:STDOUT:     import Core//prelude/operators/comparison
+// CHECK:STDOUT:     import Core//prelude/types/bool
+// CHECK:STDOUT:   }
 // CHECK:STDOUT:   %.loc6_9.1: %.1 = tuple_literal ()
 // CHECK:STDOUT:   %.loc6_9.2: type = converted %.loc6_9.1, constants.%.1 [template = constants.%.1]
 // CHECK:STDOUT:   %a.var: ref %.1 = var a
@@ -1314,11 +1386,11 @@ import library "extern_api";
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref.1: %A.type = import_ref ir1, inst+3, loaded [template = constants.%A]
-// CHECK:STDOUT:   %import_ref.2 = import_ref ir1, inst+22, unloaded
-// CHECK:STDOUT:   %import_ref.3 = import_ref ir1, inst+44, unloaded
-// CHECK:STDOUT:   %import_ref.4 = import_ref ir1, inst+47, unloaded
-// CHECK:STDOUT:   %import_ref.5 = import_ref ir1, inst+51, unloaded
+// CHECK:STDOUT:   %import_ref.1: %A.type = import_ref Main//api, inst+3, loaded [template = constants.%A]
+// CHECK:STDOUT:   %import_ref.2 = import_ref Main//api, inst+22, unloaded
+// CHECK:STDOUT:   %import_ref.3 = import_ref Main//api, inst+44, unloaded
+// CHECK:STDOUT:   %import_ref.4 = import_ref Main//api, inst+47, unloaded
+// CHECK:STDOUT:   %import_ref.5 = import_ref Main//api, inst+51, unloaded
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
@@ -1333,11 +1405,19 @@ import library "extern_api";
 // CHECK:STDOUT:   }
 // CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %default.import = import <invalid>
-// CHECK:STDOUT:   %import_ref: <namespace> = import_ref ir1, inst+50, loaded
+// CHECK:STDOUT:   %import_ref: <namespace> = import_ref Main//api, inst+50, loaded
 // CHECK:STDOUT:   %NS: <namespace> = namespace %import_ref, [template] {
 // CHECK:STDOUT:     .E = imports.%import_ref.5
 // CHECK:STDOUT:   }
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {}
+// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT:     import Core//prelude
+// CHECK:STDOUT:     import Core//prelude/operators
+// CHECK:STDOUT:     import Core//prelude/types
+// CHECK:STDOUT:     import Core//prelude/operators/arithmetic
+// CHECK:STDOUT:     import Core//prelude/operators/bitwise
+// CHECK:STDOUT:     import Core//prelude/operators/comparison
+// CHECK:STDOUT:     import Core//prelude/types/bool
+// CHECK:STDOUT:   }
 // CHECK:STDOUT:   %.loc6_9.1: %.1 = tuple_literal ()
 // CHECK:STDOUT:   %.loc6_9.2: type = converted %.loc6_9.1, constants.%.1 [template = constants.%.1]
 // CHECK:STDOUT:   %a.var: ref %.1 = var a
@@ -1358,11 +1438,11 @@ import library "extern_api";
 // CHECK:STDOUT: --- unloaded.carbon
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref.1 = import_ref ir1, inst+3, unloaded
-// CHECK:STDOUT:   %import_ref.2 = import_ref ir1, inst+22, unloaded
-// CHECK:STDOUT:   %import_ref.3 = import_ref ir1, inst+44, unloaded
-// CHECK:STDOUT:   %import_ref.4 = import_ref ir1, inst+47, unloaded
-// CHECK:STDOUT:   %import_ref.5 = import_ref ir1, inst+51, unloaded
+// CHECK:STDOUT:   %import_ref.1 = import_ref Main//api, inst+3, unloaded
+// CHECK:STDOUT:   %import_ref.2 = import_ref Main//api, inst+22, unloaded
+// CHECK:STDOUT:   %import_ref.3 = import_ref Main//api, inst+44, unloaded
+// CHECK:STDOUT:   %import_ref.4 = import_ref Main//api, inst+47, unloaded
+// CHECK:STDOUT:   %import_ref.5 = import_ref Main//api, inst+51, unloaded
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
@@ -1376,21 +1456,29 @@ import library "extern_api";
 // CHECK:STDOUT:   }
 // CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %default.import = import <invalid>
-// CHECK:STDOUT:   %import_ref: <namespace> = import_ref ir1, inst+50, loaded
+// CHECK:STDOUT:   %import_ref: <namespace> = import_ref Main//api, inst+50, loaded
 // CHECK:STDOUT:   %NS: <namespace> = namespace %import_ref, [template] {
 // CHECK:STDOUT:     .E = imports.%import_ref.5
 // CHECK:STDOUT:   }
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {}
+// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT:     import Core//prelude
+// CHECK:STDOUT:     import Core//prelude/operators
+// CHECK:STDOUT:     import Core//prelude/types
+// CHECK:STDOUT:     import Core//prelude/operators/arithmetic
+// CHECK:STDOUT:     import Core//prelude/operators/bitwise
+// CHECK:STDOUT:     import Core//prelude/operators/comparison
+// CHECK:STDOUT:     import Core//prelude/types/bool
+// CHECK:STDOUT:   }
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: --- unloaded_extern.carbon
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref.1 = import_ref ir1, inst+3, unloaded
-// CHECK:STDOUT:   %import_ref.2 = import_ref ir1, inst+22, unloaded
-// CHECK:STDOUT:   %import_ref.3 = import_ref ir1, inst+44, unloaded
-// CHECK:STDOUT:   %import_ref.4 = import_ref ir1, inst+47, unloaded
-// CHECK:STDOUT:   %import_ref.5 = import_ref ir1, inst+51, unloaded
+// CHECK:STDOUT:   %import_ref.1 = import_ref Main//extern_api, inst+3, unloaded
+// CHECK:STDOUT:   %import_ref.2 = import_ref Main//extern_api, inst+22, unloaded
+// CHECK:STDOUT:   %import_ref.3 = import_ref Main//extern_api, inst+44, unloaded
+// CHECK:STDOUT:   %import_ref.4 = import_ref Main//extern_api, inst+47, unloaded
+// CHECK:STDOUT:   %import_ref.5 = import_ref Main//extern_api, inst+51, unloaded
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
@@ -1404,26 +1492,34 @@ import library "extern_api";
 // CHECK:STDOUT:   }
 // CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %default.import = import <invalid>
-// CHECK:STDOUT:   %import_ref: <namespace> = import_ref ir1, inst+50, loaded
+// CHECK:STDOUT:   %import_ref: <namespace> = import_ref Main//extern_api, inst+50, loaded
 // CHECK:STDOUT:   %NS: <namespace> = namespace %import_ref, [template] {
 // CHECK:STDOUT:     .E = imports.%import_ref.5
 // CHECK:STDOUT:   }
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {}
+// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT:     import Core//prelude
+// CHECK:STDOUT:     import Core//prelude/operators
+// CHECK:STDOUT:     import Core//prelude/types
+// CHECK:STDOUT:     import Core//prelude/operators/arithmetic
+// CHECK:STDOUT:     import Core//prelude/operators/bitwise
+// CHECK:STDOUT:     import Core//prelude/operators/comparison
+// CHECK:STDOUT:     import Core//prelude/types/bool
+// CHECK:STDOUT:   }
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: --- fail_todo_loaded_merge.carbon
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref.1 = import_ref ir1, inst+3, unloaded
-// CHECK:STDOUT:   %import_ref.2 = import_ref ir1, inst+22, unloaded
-// CHECK:STDOUT:   %import_ref.3 = import_ref ir1, inst+44, unloaded
-// CHECK:STDOUT:   %import_ref.4 = import_ref ir1, inst+47, unloaded
-// CHECK:STDOUT:   %import_ref.5 = import_ref ir1, inst+51, unloaded
-// CHECK:STDOUT:   %import_ref.6 = import_ref ir2, inst+3, unloaded
-// CHECK:STDOUT:   %import_ref.7 = import_ref ir2, inst+22, unloaded
-// CHECK:STDOUT:   %import_ref.8 = import_ref ir2, inst+44, unloaded
-// CHECK:STDOUT:   %import_ref.9 = import_ref ir2, inst+47, unloaded
-// CHECK:STDOUT:   %import_ref.10 = import_ref ir2, inst+51, unloaded
+// CHECK:STDOUT:   %import_ref.1 = import_ref Main//api, inst+3, unloaded
+// CHECK:STDOUT:   %import_ref.2 = import_ref Main//api, inst+22, unloaded
+// CHECK:STDOUT:   %import_ref.3 = import_ref Main//api, inst+44, unloaded
+// CHECK:STDOUT:   %import_ref.4 = import_ref Main//api, inst+47, unloaded
+// CHECK:STDOUT:   %import_ref.5 = import_ref Main//api, inst+51, unloaded
+// CHECK:STDOUT:   %import_ref.6 = import_ref Main//extern_api, inst+3, unloaded
+// CHECK:STDOUT:   %import_ref.7 = import_ref Main//extern_api, inst+22, unloaded
+// CHECK:STDOUT:   %import_ref.8 = import_ref Main//extern_api, inst+44, unloaded
+// CHECK:STDOUT:   %import_ref.9 = import_ref Main//extern_api, inst+47, unloaded
+// CHECK:STDOUT:   %import_ref.10 = import_ref Main//extern_api, inst+51, unloaded
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
@@ -1437,10 +1533,18 @@ import library "extern_api";
 // CHECK:STDOUT:   }
 // CHECK:STDOUT:   %Core.import = import Core
 // CHECK:STDOUT:   %default.import = import <invalid>
-// CHECK:STDOUT:   %import_ref: <namespace> = import_ref ir1, inst+50, loaded
+// CHECK:STDOUT:   %import_ref: <namespace> = import_ref Main//api, inst+50, loaded
 // CHECK:STDOUT:   %NS: <namespace> = namespace %import_ref, [template] {
 // CHECK:STDOUT:     .E = imports.%import_ref.5
 // CHECK:STDOUT:   }
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {}
+// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT:     import Core//prelude
+// CHECK:STDOUT:     import Core//prelude/operators
+// CHECK:STDOUT:     import Core//prelude/types
+// CHECK:STDOUT:     import Core//prelude/operators/arithmetic
+// CHECK:STDOUT:     import Core//prelude/operators/bitwise
+// CHECK:STDOUT:     import Core//prelude/operators/comparison
+// CHECK:STDOUT:     import Core//prelude/types/bool
+// CHECK:STDOUT:   }
 // CHECK:STDOUT: }
 // CHECK:STDOUT:

toolchain/check/testdata/function/declaration/no_prelude/export_name.carbon

@@ -64,7 +64,7 @@ var f: () = F();
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref: %F.type = import_ref ir1, inst+1, loaded [template = constants.%F]
+// CHECK:STDOUT:   %import_ref: %F.type = import_ref Main//base, inst+1, loaded [template = constants.%F]
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
@@ -86,7 +86,7 @@ var f: () = F();
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref: %F.type = import_ref ir1, inst+7, loaded [template = constants.%F]
+// CHECK:STDOUT:   %import_ref: %F.type = import_ref Main//export, inst+7, loaded [template = constants.%F]
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {

toolchain/check/testdata/function/declaration/no_prelude/fail_import_incomplete_return.carbon

@@ -171,14 +171,14 @@ fn CallFAndGIncomplete() {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref.1 = import_ref ir1, inst+1, unloaded
-// CHECK:STDOUT:   %import_ref.2 = import_ref ir1, inst+3, unloaded
-// CHECK:STDOUT:   %import_ref.3: %ReturnCUnused.type = import_ref ir1, inst+7, loaded [template = constants.%ReturnCUnused]
-// CHECK:STDOUT:   %import_ref.4: %ReturnCUsed.type = import_ref ir1, inst+13, loaded [template = constants.%ReturnCUsed]
-// CHECK:STDOUT:   %import_ref.5: %ReturnDUnused.type = import_ref ir1, inst+18, loaded [template = constants.%ReturnDUnused]
-// CHECK:STDOUT:   %import_ref.6: %ReturnDUsed.type = import_ref ir1, inst+23, loaded [template = constants.%ReturnDUsed]
-// CHECK:STDOUT:   %import_ref.7 = import_ref ir1, inst+26, unloaded
-// CHECK:STDOUT:   %import_ref.8 = import_ref ir1, inst+4, unloaded
+// CHECK:STDOUT:   %import_ref.1 = import_ref Main//api, inst+1, unloaded
+// CHECK:STDOUT:   %import_ref.2 = import_ref Main//api, inst+3, unloaded
+// CHECK:STDOUT:   %import_ref.3: %ReturnCUnused.type = import_ref Main//api, inst+7, loaded [template = constants.%ReturnCUnused]
+// CHECK:STDOUT:   %import_ref.4: %ReturnCUsed.type = import_ref Main//api, inst+13, loaded [template = constants.%ReturnCUsed]
+// CHECK:STDOUT:   %import_ref.5: %ReturnDUnused.type = import_ref Main//api, inst+18, loaded [template = constants.%ReturnDUnused]
+// CHECK:STDOUT:   %import_ref.6: %ReturnDUsed.type = import_ref Main//api, inst+23, loaded [template = constants.%ReturnDUsed]
+// CHECK:STDOUT:   %import_ref.7 = import_ref Main//api, inst+26, unloaded
+// CHECK:STDOUT:   %import_ref.8 = import_ref Main//api, inst+4, unloaded
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {

toolchain/check/testdata/function/declaration/no_prelude/implicit_import.carbon

@@ -93,7 +93,7 @@ extern fn A();
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref: %A.type = import_ref ir0, inst+1, loaded [template = constants.%A]
+// CHECK:STDOUT:   %import_ref: %A.type = import_ref Main//basic, inst+1, loaded [template = constants.%A]
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
@@ -136,7 +136,7 @@ extern fn A();
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref: %A.type = import_ref ir0, inst+1, loaded [template = constants.%A]
+// CHECK:STDOUT:   %import_ref: %A.type = import_ref Main//extern_api, inst+1, loaded [template = constants.%A]
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
@@ -176,7 +176,7 @@ extern fn A();
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref: %A.type = import_ref ir0, inst+1, loaded [template = constants.%A]
+// CHECK:STDOUT:   %import_ref: %A.type = import_ref Main//extern_impl, inst+1, loaded [template = constants.%A]
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {

toolchain/check/testdata/function/declaration/no_prelude/no_definition_in_impl_file.carbon

@@ -97,7 +97,7 @@ fn D();
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref: %A.type = import_ref ir0, inst+1, loaded [template = constants.%A]
+// CHECK:STDOUT:   %import_ref: %A.type = import_ref Main//decl_in_api_definition_in_impl, inst+1, loaded [template = constants.%A]
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
@@ -124,7 +124,7 @@ fn D();
 // CHECK:STDOUT: --- use_decl_in_api.impl.carbon
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref = import_ref ir1, inst+1, unloaded
+// CHECK:STDOUT:   %import_ref = import_ref Main//decl_in_api_definition_in_impl, inst+1, unloaded
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
@@ -155,7 +155,7 @@ fn D();
 // CHECK:STDOUT: --- decl_only_in_api.impl.carbon
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref = import_ref ir0, inst+1, unloaded
+// CHECK:STDOUT:   %import_ref = import_ref Main//decl_only_in_api, inst+1, unloaded
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
@@ -192,7 +192,7 @@ fn D();
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref: %C.type = import_ref ir0, inst+1, loaded [template = constants.%C]
+// CHECK:STDOUT:   %import_ref: %C.type = import_ref Main//decl_in_api_decl_in_impl, inst+1, loaded [template = constants.%C]
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {

toolchain/check/testdata/function/declaration/param_same_name.carbon

@@ -25,8 +25,8 @@ fn G(a: i32);
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: imports {
-// CHECK:STDOUT:   %import_ref.1: %Int32.type = import_ref ir3, inst+4, loaded [template = constants.%Int32]
-// CHECK:STDOUT:   %import_ref.2: %Int32.type = import_ref ir3, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.1: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
+// CHECK:STDOUT:   %import_ref.2: %Int32.type = import_ref Core//prelude/types, inst+4, loaded [template = constants.%Int32]
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: file {
@@ -36,7 +36,15 @@ fn G(a: i32);
 // CHECK:STDOUT:     .G = %G.decl
 // CHECK:STDOUT:   }
 // CHECK:STDOUT:   %Core.import = import Core
-// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {}
+// CHECK:STDOUT:   %Core: <namespace> = namespace %Core.import, [template] {
+// CHECK:STDOUT:     import Core//prelude
+// CHECK:STDOUT:     import Core//prelude/operators
+// CHECK:STDOUT:     import Core//prelude/types
+// CHECK:STDOUT:     import Core//prelude/operators/arithmetic
+// CHECK:STDOUT:     import Core//prelude/operators/bitwise
+// CHECK:STDOUT:     import Core//prelude/operators/comparison
+// CHECK:STDOUT:     import Core//prelude/types/bool
+// CHECK:STDOUT:   }
 // CHECK:STDOUT:   %F.decl: %F.type = fn_decl @F [template = constants.%F] {
 // CHECK:STDOUT:     %int.make_type_32.loc11: init type = call constants.%Int32() [template = i32]
 // CHECK:STDOUT:     %.loc11_9.1: type = value_of_initializer %int.make_type_32.loc11 [template = i32]