Fix mangling collision for C++ class template specializations (#7269)

Carbon-side thunks (for example the `Copy`/`Destroy` witness thunks
generated for imported C++ types) are mangled by Carbon, and their names
incorporate a fingerprint of the involved types. The instruction
fingerprinter identifies a class only by its name and parent scope,
which is sufficient for Carbon classes but not for imported C++ classes:
different specializations of one class template (and other cases such as
types in anonymous namespaces) share a Carbon name and parent scope. As
a result, the thunks for two distinct specializations could mangle to
the same name, producing a single LLVM function with two definitions and
failing `verifyModule` during lowering.

When fingerprinting a class imported from C++, also include the Clang
mangled name of its type.

Test: toolchain/lower/testdata/interop/cpp/thunks.carbon gains a split
with two specializations of one class template, each requiring a thunk;
their thunks now get distinct mangled names instead of colliding.

Assisted-by: Claude Code

---------

Co-authored-by: Christopher Di Bella <cjdb.ns@gmail.com>

toolchain/lower/testdata/interop/cpp/class/import/dynamic.carbon

@@ -171,7 +171,7 @@ auto DoThing() -> void {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define weak_odr void @"_COp.9262bcc12ced4e1e:core.Destroy.Core"(ptr %self) #5 !dbg !33 {
+// CHECK:STDOUT: define weak_odr void @"_COp.47e6e98bb48502be:core.Destroy.Core"(ptr %self) #5 !dbg !33 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   ret void, !dbg !36
 // CHECK:STDOUT: }
@@ -297,7 +297,7 @@ auto DoThing() -> void {
 // CHECK:STDOUT: !30 = !{!31}
 // CHECK:STDOUT: !31 = !DILocalVariable(arg: 1, scope: !29, type: !21)
 // CHECK:STDOUT: !32 = !DILocation(line: 22, column: 1, scope: !29)
-// CHECK:STDOUT: !33 = distinct !DISubprogram(name: "Op", linkageName: "_COp.9262bcc12ced4e1e:core.Destroy.Core", scope: null, file: !6, line: 22, type: !19, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !34)
+// CHECK:STDOUT: !33 = distinct !DISubprogram(name: "Op", linkageName: "_COp.47e6e98bb48502be:core.Destroy.Core", scope: null, file: !6, line: 22, type: !19, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !34)
 // CHECK:STDOUT: !34 = !{!35}
 // CHECK:STDOUT: !35 = !DILocalVariable(arg: 1, scope: !33, type: !21)
 // CHECK:STDOUT: !36 = !DILocation(line: 22, column: 1, scope: !33)

toolchain/lower/testdata/interop/cpp/class/virtual_fn.carbon

@@ -209,7 +209,7 @@ void delete_new_Base() {
 // CHECK:STDOUT: declare void @_ZN1AD1Ev(ptr noundef nonnull align 8 dead_on_return(8) dereferenceable(8)) unnamed_addr #7
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define weak_odr void @"_COp.bce205344e07c31d:core.Destroy.Core"(ptr %self) #8 !dbg !29 {
+// CHECK:STDOUT: define weak_odr void @"_COp.6a9ecc3bdf183bcf:core.Destroy.Core"(ptr %self) #8 !dbg !29 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   ret void, !dbg !32
 // CHECK:STDOUT: }
@@ -380,7 +380,7 @@ void delete_new_Base() {
 // CHECK:STDOUT: !26 = !{!27}
 // CHECK:STDOUT: !27 = !DILocalVariable(arg: 1, scope: !22, type: !25)
 // CHECK:STDOUT: !28 = !DILocation(line: 12, column: 1, scope: !22)
-// CHECK:STDOUT: !29 = distinct !DISubprogram(name: "Op", linkageName: "_COp.bce205344e07c31d:core.Destroy.Core", scope: null, file: !6, line: 12, type: !23, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !30)
+// CHECK:STDOUT: !29 = distinct !DISubprogram(name: "Op", linkageName: "_COp.6a9ecc3bdf183bcf:core.Destroy.Core", scope: null, file: !6, line: 12, type: !23, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !30)
 // CHECK:STDOUT: !30 = !{!31}
 // CHECK:STDOUT: !31 = !DILocalVariable(arg: 1, scope: !29, type: !25)
 // CHECK:STDOUT: !32 = !DILocation(line: 12, column: 1, scope: !29)

toolchain/lower/testdata/interop/cpp/constructor.carbon

@@ -281,7 +281,7 @@ fn Four() {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   %_.var = alloca [8 x i8], align 1, !dbg !14
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !14
-// CHECK:STDOUT:   call void @"_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.2603c91dd66a1dca"(ptr %_.var), !dbg !14
+// CHECK:STDOUT:   call void @"_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.4fdc745d4b6d0e3c"(ptr %_.var), !dbg !14
 // CHECK:STDOUT:   ret void, !dbg !15
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
@@ -296,7 +296,7 @@ fn Four() {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: alwaysinline nounwind
-// CHECK:STDOUT: define void @"_COp:thunk:Default.5648bcc2d6c775b7.Core:C.Cpp"(ptr sret([8 x i8]) %return) #2 !dbg !19 {
+// CHECK:STDOUT: define void @"_COp:thunk:Default.08e786f435a99766.Core:C.Cpp"(ptr sret([8 x i8]) %return) #2 !dbg !19 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   call void @_ZN1CC1Ev.carbon_thunk.(ptr %return), !dbg !24
 // CHECK:STDOUT:   ret void, !dbg !24
@@ -306,8 +306,8 @@ fn Four() {
 // CHECK:STDOUT: declare void @llvm.lifetime.start.p0(ptr captures(none)) #3
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define linkonce_odr void @"_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.2603c91dd66a1dca"(ptr sret([8 x i8]) %return) #0 !dbg !25 {
-// CHECK:STDOUT:   call void @"_COp:thunk:Default.5648bcc2d6c775b7.Core:C.Cpp"(ptr %return), !dbg !27
+// CHECK:STDOUT: define linkonce_odr void @"_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.4fdc745d4b6d0e3c"(ptr sret([8 x i8]) %return) #0 !dbg !25 {
+// CHECK:STDOUT:   call void @"_COp:thunk:Default.08e786f435a99766.Core:C.Cpp"(ptr %return), !dbg !27
 // CHECK:STDOUT:   ret void, !dbg !28
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
@@ -353,13 +353,13 @@ fn Four() {
 // CHECK:STDOUT: !16 = !{!17, !17, i64 0}
 // CHECK:STDOUT: !17 = !{!"p1 _ZTS1C", !18, i64 0}
 // CHECK:STDOUT: !18 = !{!"any pointer", !9, i64 0}
-// CHECK:STDOUT: !19 = distinct !DISubprogram(name: "Op", linkageName: "_COp:thunk:Default.5648bcc2d6c775b7.Core:C.Cpp", scope: null, file: !20, line: 4, type: !21, spFlags: DISPFlagDefinition, unit: !5)
+// CHECK:STDOUT: !19 = distinct !DISubprogram(name: "Op", linkageName: "_COp:thunk:Default.08e786f435a99766.Core:C.Cpp", scope: null, file: !20, line: 4, type: !21, spFlags: DISPFlagDefinition, unit: !5)
 // CHECK:STDOUT: !20 = !DIFile(filename: "./default.h", directory: "")
 // CHECK:STDOUT: !21 = !DISubroutineType(types: !22)
 // CHECK:STDOUT: !22 = !{!23}
 // CHECK:STDOUT: !23 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: null, size: 64)
 // CHECK:STDOUT: !24 = !DILocation(line: 4, column: 3, scope: !19)
-// CHECK:STDOUT: !25 = distinct !DISubprogram(name: "Op", linkageName: "_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.2603c91dd66a1dca", scope: null, file: !26, line: 9, type: !21, spFlags: DISPFlagDefinition, unit: !5)
+// CHECK:STDOUT: !25 = distinct !DISubprogram(name: "Op", linkageName: "_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.4fdc745d4b6d0e3c", scope: null, file: !26, line: 9, type: !21, spFlags: DISPFlagDefinition, unit: !5)
 // CHECK:STDOUT: !26 = !DIFile(filename: "min_prelude/parts/default.carbon", directory: "")
 // CHECK:STDOUT: !27 = !DILocation(line: 9, column: 28, scope: !25)
 // CHECK:STDOUT: !28 = !DILocation(line: 9, column: 21, scope: !25)
@@ -388,11 +388,11 @@ fn Four() {
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc8_65.1.temp), !dbg !14
 // CHECK:STDOUT:   call void @_ZN26ImplicitlyDefaultedDefaultC1Ev.carbon_thunk.(ptr %.loc8_65.1.temp), !dbg !14
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var.loc9), !dbg !15
-// CHECK:STDOUT:   call void @"_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.2db09a503899761f"(ptr %_.var.loc9), !dbg !15
+// CHECK:STDOUT:   call void @"_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.dc183edbabc24d2f"(ptr %_.var.loc9), !dbg !15
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc12_65.1.temp), !dbg !16
 // CHECK:STDOUT:   call void @_ZN26ExplicitlyDefaultedDefaultC1Ev.carbon_thunk.(ptr %.loc12_65.1.temp), !dbg !16
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var.loc13), !dbg !17
-// CHECK:STDOUT:   call void @"_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.0dfbcd9a7c1791ba"(ptr %_.var.loc13), !dbg !17
+// CHECK:STDOUT:   call void @"_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.44ad2ae60410d16d"(ptr %_.var.loc13), !dbg !17
 // CHECK:STDOUT:   ret void, !dbg !18
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
@@ -407,7 +407,7 @@ fn Four() {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: alwaysinline nounwind
-// CHECK:STDOUT: define void @"_COp:thunk:Default.40902cf3dea87d9c.Core:ImplicitlyDefaultedDefault.Cpp"(ptr sret([4 x i8]) %return) #2 !dbg !22 {
+// CHECK:STDOUT: define void @"_COp:thunk:Default.1458cb9e3f45d9d7.Core:ImplicitlyDefaultedDefault.Cpp"(ptr sret([4 x i8]) %return) #2 !dbg !22 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   call void @_ZN26ImplicitlyDefaultedDefaultC1Ev.carbon_thunk.(ptr %return), !dbg !27
 // CHECK:STDOUT:   ret void, !dbg !27
@@ -424,7 +424,7 @@ fn Four() {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: alwaysinline nounwind
-// CHECK:STDOUT: define void @"_COp:thunk:Default.f7ced4a20f885cf5.Core:ExplicitlyDefaultedDefault.Cpp"(ptr sret([4 x i8]) %return) #2 !dbg !30 {
+// CHECK:STDOUT: define void @"_COp:thunk:Default.16c8d515df1b6c01.Core:ExplicitlyDefaultedDefault.Cpp"(ptr sret([4 x i8]) %return) #2 !dbg !30 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   call void @_ZN26ExplicitlyDefaultedDefaultC1Ev.carbon_thunk.(ptr %return), !dbg !31
 // CHECK:STDOUT:   ret void, !dbg !31
@@ -434,14 +434,14 @@ fn Four() {
 // CHECK:STDOUT: declare void @llvm.lifetime.start.p0(ptr captures(none)) #3
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define linkonce_odr void @"_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.2db09a503899761f"(ptr sret([4 x i8]) %return) #0 !dbg !32 {
-// CHECK:STDOUT:   call void @"_COp:thunk:Default.40902cf3dea87d9c.Core:ImplicitlyDefaultedDefault.Cpp"(ptr %return), !dbg !34
+// CHECK:STDOUT: define linkonce_odr void @"_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.dc183edbabc24d2f"(ptr sret([4 x i8]) %return) #0 !dbg !32 {
+// CHECK:STDOUT:   call void @"_COp:thunk:Default.1458cb9e3f45d9d7.Core:ImplicitlyDefaultedDefault.Cpp"(ptr %return), !dbg !34
 // CHECK:STDOUT:   ret void, !dbg !35
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define linkonce_odr void @"_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.0dfbcd9a7c1791ba"(ptr sret([4 x i8]) %return) #0 !dbg !36 {
-// CHECK:STDOUT:   call void @"_COp:thunk:Default.f7ced4a20f885cf5.Core:ExplicitlyDefaultedDefault.Cpp"(ptr %return), !dbg !37
+// CHECK:STDOUT: define linkonce_odr void @"_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.44ad2ae60410d16d"(ptr sret([4 x i8]) %return) #0 !dbg !36 {
+// CHECK:STDOUT:   call void @"_COp:thunk:Default.16c8d515df1b6c01.Core:ExplicitlyDefaultedDefault.Cpp"(ptr %return), !dbg !37
 // CHECK:STDOUT:   ret void, !dbg !38
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
@@ -503,7 +503,7 @@ fn Four() {
 // CHECK:STDOUT: !19 = !{!20, !20, i64 0}
 // CHECK:STDOUT: !20 = !{!"p1 _ZTS26ImplicitlyDefaultedDefault", !21, i64 0}
 // CHECK:STDOUT: !21 = !{!"any pointer", !9, i64 0}
-// CHECK:STDOUT: !22 = distinct !DISubprogram(name: "Op", linkageName: "_COp:thunk:Default.40902cf3dea87d9c.Core:ImplicitlyDefaultedDefault.Cpp", scope: null, file: !23, line: 2, type: !24, spFlags: DISPFlagDefinition, unit: !5)
+// CHECK:STDOUT: !22 = distinct !DISubprogram(name: "Op", linkageName: "_COp:thunk:Default.1458cb9e3f45d9d7.Core:ImplicitlyDefaultedDefault.Cpp", scope: null, file: !23, line: 2, type: !24, spFlags: DISPFlagDefinition, unit: !5)
 // CHECK:STDOUT: !23 = !DIFile(filename: "./defaulted_default.h", directory: "")
 // CHECK:STDOUT: !24 = !DISubroutineType(types: !25)
 // CHECK:STDOUT: !25 = !{!26}
@@ -511,13 +511,13 @@ fn Four() {
 // CHECK:STDOUT: !27 = !DILocation(line: 2, column: 8, scope: !22)
 // CHECK:STDOUT: !28 = !{!29, !29, i64 0}
 // CHECK:STDOUT: !29 = !{!"p1 _ZTS26ExplicitlyDefaultedDefault", !21, i64 0}
-// CHECK:STDOUT: !30 = distinct !DISubprogram(name: "Op", linkageName: "_COp:thunk:Default.f7ced4a20f885cf5.Core:ExplicitlyDefaultedDefault.Cpp", scope: null, file: !23, line: 7, type: !24, spFlags: DISPFlagDefinition, unit: !5)
+// CHECK:STDOUT: !30 = distinct !DISubprogram(name: "Op", linkageName: "_COp:thunk:Default.16c8d515df1b6c01.Core:ExplicitlyDefaultedDefault.Cpp", scope: null, file: !23, line: 7, type: !24, spFlags: DISPFlagDefinition, unit: !5)
 // CHECK:STDOUT: !31 = !DILocation(line: 7, column: 3, scope: !30)
-// CHECK:STDOUT: !32 = distinct !DISubprogram(name: "Op", linkageName: "_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.2db09a503899761f", scope: null, file: !33, line: 9, type: !24, spFlags: DISPFlagDefinition, unit: !5)
+// CHECK:STDOUT: !32 = distinct !DISubprogram(name: "Op", linkageName: "_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.dc183edbabc24d2f", scope: null, file: !33, line: 9, type: !24, spFlags: DISPFlagDefinition, unit: !5)
 // CHECK:STDOUT: !33 = !DIFile(filename: "min_prelude/parts/default.carbon", directory: "")
 // CHECK:STDOUT: !34 = !DILocation(line: 9, column: 28, scope: !32)
 // CHECK:STDOUT: !35 = !DILocation(line: 9, column: 21, scope: !32)
-// CHECK:STDOUT: !36 = distinct !DISubprogram(name: "Op", linkageName: "_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.0dfbcd9a7c1791ba", scope: null, file: !33, line: 9, type: !24, spFlags: DISPFlagDefinition, unit: !5)
+// CHECK:STDOUT: !36 = distinct !DISubprogram(name: "Op", linkageName: "_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.44ad2ae60410d16d", scope: null, file: !33, line: 9, type: !24, spFlags: DISPFlagDefinition, unit: !5)
 // CHECK:STDOUT: !37 = !DILocation(line: 9, column: 28, scope: !36)
 // CHECK:STDOUT: !38 = !DILocation(line: 9, column: 21, scope: !36)
 // CHECK:STDOUT: !39 = !{!40, !8, i64 0}
@@ -552,7 +552,7 @@ fn Four() {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: alwaysinline nounwind
-// CHECK:STDOUT: define void @"_COp:thunk:Copy.83073f2d17ed2f9e.Core:Copy.Cpp"(ptr sret([4 x i8]) %return, ptr %self) #2 !dbg !22 {
+// CHECK:STDOUT: define void @"_COp:thunk:Copy.0459c72f2d146eb1.Core:Copy.Cpp"(ptr sret([4 x i8]) %return, ptr %self) #2 !dbg !22 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   call void @_ZN4CopyC1ERKS_.carbon_thunk._(ptr %self, ptr %return), !dbg !26
 // CHECK:STDOUT:   ret void, !dbg !26
@@ -595,7 +595,7 @@ fn Four() {
 // CHECK:STDOUT: !19 = !{!20, !20, i64 0}
 // CHECK:STDOUT: !20 = !{!"p1 _ZTS4Copy", !21, i64 0}
 // CHECK:STDOUT: !21 = !{!"any pointer", !9, i64 0}
-// CHECK:STDOUT: !22 = distinct !DISubprogram(name: "Op", linkageName: "_COp:thunk:Copy.83073f2d17ed2f9e.Core:Copy.Cpp", scope: null, file: !23, line: 5, type: !12, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !24)
+// CHECK:STDOUT: !22 = distinct !DISubprogram(name: "Op", linkageName: "_COp:thunk:Copy.0459c72f2d146eb1.Core:Copy.Cpp", scope: null, file: !23, line: 5, type: !12, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !24)
 // CHECK:STDOUT: !23 = !DIFile(filename: "./copy.h", directory: "")
 // CHECK:STDOUT: !24 = !{!25}
 // CHECK:STDOUT: !25 = !DILocalVariable(arg: 1, scope: !22, type: !14)

toolchain/lower/testdata/interop/cpp/operators.carbon

@@ -88,7 +88,7 @@ fn Driver(x: Cpp.A, y: Cpp.A) {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CDriver.Main(ptr %x, ptr %y) #0 !dbg !11 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   call void @_CCheckEqWith.Main.8514cfa07ba3e7b7(ptr %x, ptr %y), !dbg !18
+// CHECK:STDOUT:   call void @_CCheckEqWith.Main.04aa760156d52229(ptr %x, ptr %y), !dbg !18
 // CHECK:STDOUT:   ret void, !dbg !19
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
@@ -145,7 +145,7 @@ fn Driver(x: Cpp.A, y: Cpp.A) {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: alwaysinline nounwind
-// CHECK:STDOUT: define i1 @"_CEqual:thunk:EqWith.f46538683c1a9318.Core:Cpp"(ptr %self, ptr %other) #2 !dbg !28 {
+// CHECK:STDOUT: define i1 @"_CEqual:thunk:EqWith.179c7169d26a9459.Core:Cpp"(ptr %self, ptr %other) #2 !dbg !28 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   %.3.temp = alloca i1, align 1, !dbg !34
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.3.temp), !dbg !34
@@ -155,7 +155,7 @@ fn Driver(x: Cpp.A, y: Cpp.A) {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: alwaysinline nounwind
-// CHECK:STDOUT: define i1 @"_CNotEqual:thunk:EqWith.f46538683c1a9318.Core:Cpp"(ptr %self, ptr %other) #2 !dbg !35 {
+// CHECK:STDOUT: define i1 @"_CNotEqual:thunk:EqWith.179c7169d26a9459.Core:Cpp"(ptr %self, ptr %other) #2 !dbg !35 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   %.3.temp = alloca i1, align 1, !dbg !39
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.3.temp), !dbg !39
@@ -165,10 +165,10 @@ fn Driver(x: Cpp.A, y: Cpp.A) {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define linkonce_odr void @_CCheckEqWith.Main.8514cfa07ba3e7b7(ptr %x, ptr %y) #0 !dbg !40 {
+// CHECK:STDOUT: define linkonce_odr void @_CCheckEqWith.Main.04aa760156d52229(ptr %x, ptr %y) #0 !dbg !40 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %EqWith.WithSelf.Equal.call = call i1 @"_CEqual:thunk:EqWith.f46538683c1a9318.Core:Cpp"(ptr %x, ptr %y), !dbg !44
-// CHECK:STDOUT:   %EqWith.WithSelf.NotEqual.call = call i1 @"_CNotEqual:thunk:EqWith.f46538683c1a9318.Core:Cpp"(ptr %x, ptr %y), !dbg !45
+// CHECK:STDOUT:   %EqWith.WithSelf.Equal.call = call i1 @"_CEqual:thunk:EqWith.179c7169d26a9459.Core:Cpp"(ptr %x, ptr %y), !dbg !44
+// CHECK:STDOUT:   %EqWith.WithSelf.NotEqual.call = call i1 @"_CNotEqual:thunk:EqWith.179c7169d26a9459.Core:Cpp"(ptr %x, ptr %y), !dbg !45
 // CHECK:STDOUT:   ret void, !dbg !46
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
@@ -259,19 +259,19 @@ fn Driver(x: Cpp.A, y: Cpp.A) {
 // CHECK:STDOUT: !25 = !{i64 0, i64 4, !7}
 // CHECK:STDOUT: !26 = !{!27, !27, i64 0}
 // CHECK:STDOUT: !27 = !{!"bool", !9, i64 0}
-// CHECK:STDOUT: !28 = distinct !DISubprogram(name: "Equal", linkageName: "_CEqual:thunk:EqWith.f46538683c1a9318.Core:Cpp", scope: null, file: !6, line: 8, type: !29, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !31)
+// CHECK:STDOUT: !28 = distinct !DISubprogram(name: "Equal", linkageName: "_CEqual:thunk:EqWith.179c7169d26a9459.Core:Cpp", scope: null, file: !6, line: 8, type: !29, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !31)
 // CHECK:STDOUT: !29 = !DISubroutineType(types: !30)
 // CHECK:STDOUT: !30 = !{!14, !14, !14}
 // CHECK:STDOUT: !31 = !{!32, !33}
 // CHECK:STDOUT: !32 = !DILocalVariable(arg: 1, scope: !28, type: !14)
 // CHECK:STDOUT: !33 = !DILocalVariable(arg: 2, scope: !28, type: !14)
 // CHECK:STDOUT: !34 = !DILocation(line: 8, column: 15, scope: !28)
-// CHECK:STDOUT: !35 = distinct !DISubprogram(name: "NotEqual", linkageName: "_CNotEqual:thunk:EqWith.f46538683c1a9318.Core:Cpp", scope: null, file: !6, line: 12, type: !29, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !36)
+// CHECK:STDOUT: !35 = distinct !DISubprogram(name: "NotEqual", linkageName: "_CNotEqual:thunk:EqWith.179c7169d26a9459.Core:Cpp", scope: null, file: !6, line: 12, type: !29, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !36)
 // CHECK:STDOUT: !36 = !{!37, !38}
 // CHECK:STDOUT: !37 = !DILocalVariable(arg: 1, scope: !35, type: !14)
 // CHECK:STDOUT: !38 = !DILocalVariable(arg: 2, scope: !35, type: !14)
 // CHECK:STDOUT: !39 = !DILocation(line: 12, column: 15, scope: !35)
-// CHECK:STDOUT: !40 = distinct !DISubprogram(name: "CheckEqWith", linkageName: "_CCheckEqWith.Main.8514cfa07ba3e7b7", scope: null, file: !6, line: 18, type: !12, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !41)
+// CHECK:STDOUT: !40 = distinct !DISubprogram(name: "CheckEqWith", linkageName: "_CCheckEqWith.Main.04aa760156d52229", scope: null, file: !6, line: 18, type: !12, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !41)
 // CHECK:STDOUT: !41 = !{!42, !43}
 // CHECK:STDOUT: !42 = !DILocalVariable(arg: 1, scope: !40, type: !14)
 // CHECK:STDOUT: !43 = !DILocalVariable(arg: 2, scope: !40, type: !14)
@@ -298,7 +298,7 @@ fn Driver(x: Cpp.A, y: Cpp.A) {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CDriver.Main(ptr %x, ptr %y) #0 !dbg !11 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   call void @_CCheckOrderedWith.Main.cf2c934aa0200133(ptr %x, ptr %y), !dbg !18
+// CHECK:STDOUT:   call void @_CCheckOrderedWith.Main.9c69d70a853113d6(ptr %x, ptr %y), !dbg !18
 // CHECK:STDOUT:   ret void, !dbg !19
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
@@ -407,7 +407,7 @@ fn Driver(x: Cpp.A, y: Cpp.A) {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: alwaysinline nounwind
-// CHECK:STDOUT: define i1 @"_CLess:thunk:OrderedWith.76d9c95e44fa79ac.Core:Cpp"(ptr %self, ptr %other) #2 !dbg !28 {
+// CHECK:STDOUT: define i1 @"_CLess:thunk:OrderedWith.081cd53d46d5db04.Core:Cpp"(ptr %self, ptr %other) #2 !dbg !28 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   %.3.temp = alloca i1, align 1, !dbg !34
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.3.temp), !dbg !34
@@ -417,7 +417,7 @@ fn Driver(x: Cpp.A, y: Cpp.A) {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: alwaysinline nounwind
-// CHECK:STDOUT: define i1 @"_CLessOrEquivalent:thunk:OrderedWith.76d9c95e44fa79ac.Core:Cpp"(ptr %self, ptr %other) #2 !dbg !35 {
+// CHECK:STDOUT: define i1 @"_CLessOrEquivalent:thunk:OrderedWith.081cd53d46d5db04.Core:Cpp"(ptr %self, ptr %other) #2 !dbg !35 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   %.3.temp = alloca i1, align 1, !dbg !39
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.3.temp), !dbg !39
@@ -427,7 +427,7 @@ fn Driver(x: Cpp.A, y: Cpp.A) {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: alwaysinline nounwind
-// CHECK:STDOUT: define i1 @"_CGreater:thunk:OrderedWith.76d9c95e44fa79ac.Core:Cpp"(ptr %self, ptr %other) #2 !dbg !40 {
+// CHECK:STDOUT: define i1 @"_CGreater:thunk:OrderedWith.081cd53d46d5db04.Core:Cpp"(ptr %self, ptr %other) #2 !dbg !40 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   %.3.temp = alloca i1, align 1, !dbg !44
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.3.temp), !dbg !44
@@ -437,7 +437,7 @@ fn Driver(x: Cpp.A, y: Cpp.A) {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: alwaysinline nounwind
-// CHECK:STDOUT: define i1 @"_CGreaterOrEquivalent:thunk:OrderedWith.76d9c95e44fa79ac.Core:Cpp"(ptr %self, ptr %other) #2 !dbg !45 {
+// CHECK:STDOUT: define i1 @"_CGreaterOrEquivalent:thunk:OrderedWith.081cd53d46d5db04.Core:Cpp"(ptr %self, ptr %other) #2 !dbg !45 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   %.3.temp = alloca i1, align 1, !dbg !49
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.3.temp), !dbg !49
@@ -447,12 +447,12 @@ fn Driver(x: Cpp.A, y: Cpp.A) {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define linkonce_odr void @_CCheckOrderedWith.Main.cf2c934aa0200133(ptr %x, ptr %y) #0 !dbg !50 {
+// CHECK:STDOUT: define linkonce_odr void @_CCheckOrderedWith.Main.9c69d70a853113d6(ptr %x, ptr %y) #0 !dbg !50 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %OrderedWith.WithSelf.Less.call = call i1 @"_CLess:thunk:OrderedWith.76d9c95e44fa79ac.Core:Cpp"(ptr %x, ptr %y), !dbg !54
-// CHECK:STDOUT:   %OrderedWith.WithSelf.Greater.call = call i1 @"_CGreater:thunk:OrderedWith.76d9c95e44fa79ac.Core:Cpp"(ptr %x, ptr %y), !dbg !55
-// CHECK:STDOUT:   %OrderedWith.WithSelf.LessOrEquivalent.call = call i1 @"_CLessOrEquivalent:thunk:OrderedWith.76d9c95e44fa79ac.Core:Cpp"(ptr %x, ptr %y), !dbg !56
-// CHECK:STDOUT:   %OrderedWith.WithSelf.GreaterOrEquivalent.call = call i1 @"_CGreaterOrEquivalent:thunk:OrderedWith.76d9c95e44fa79ac.Core:Cpp"(ptr %x, ptr %y), !dbg !57
+// CHECK:STDOUT:   %OrderedWith.WithSelf.Less.call = call i1 @"_CLess:thunk:OrderedWith.081cd53d46d5db04.Core:Cpp"(ptr %x, ptr %y), !dbg !54
+// CHECK:STDOUT:   %OrderedWith.WithSelf.Greater.call = call i1 @"_CGreater:thunk:OrderedWith.081cd53d46d5db04.Core:Cpp"(ptr %x, ptr %y), !dbg !55
+// CHECK:STDOUT:   %OrderedWith.WithSelf.LessOrEquivalent.call = call i1 @"_CLessOrEquivalent:thunk:OrderedWith.081cd53d46d5db04.Core:Cpp"(ptr %x, ptr %y), !dbg !56
+// CHECK:STDOUT:   %OrderedWith.WithSelf.GreaterOrEquivalent.call = call i1 @"_CGreaterOrEquivalent:thunk:OrderedWith.081cd53d46d5db04.Core:Cpp"(ptr %x, ptr %y), !dbg !57
 // CHECK:STDOUT:   ret void, !dbg !58
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
@@ -586,29 +586,29 @@ fn Driver(x: Cpp.A, y: Cpp.A) {
 // CHECK:STDOUT: !25 = !{i64 0, i64 4, !7}
 // CHECK:STDOUT: !26 = !{!27, !27, i64 0}
 // CHECK:STDOUT: !27 = !{!"bool", !9, i64 0}
-// CHECK:STDOUT: !28 = distinct !DISubprogram(name: "Less", linkageName: "_CLess:thunk:OrderedWith.76d9c95e44fa79ac.Core:Cpp", scope: null, file: !6, line: 8, type: !29, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !31)
+// CHECK:STDOUT: !28 = distinct !DISubprogram(name: "Less", linkageName: "_CLess:thunk:OrderedWith.081cd53d46d5db04.Core:Cpp", scope: null, file: !6, line: 8, type: !29, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !31)
 // CHECK:STDOUT: !29 = !DISubroutineType(types: !30)
 // CHECK:STDOUT: !30 = !{!14, !14, !14}
 // CHECK:STDOUT: !31 = !{!32, !33}
 // CHECK:STDOUT: !32 = !DILocalVariable(arg: 1, scope: !28, type: !14)
 // CHECK:STDOUT: !33 = !DILocalVariable(arg: 2, scope: !28, type: !14)
 // CHECK:STDOUT: !34 = !DILocation(line: 8, column: 15, scope: !28)
-// CHECK:STDOUT: !35 = distinct !DISubprogram(name: "LessOrEquivalent", linkageName: "_CLessOrEquivalent:thunk:OrderedWith.76d9c95e44fa79ac.Core:Cpp", scope: null, file: !6, line: 16, type: !29, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !36)
+// CHECK:STDOUT: !35 = distinct !DISubprogram(name: "LessOrEquivalent", linkageName: "_CLessOrEquivalent:thunk:OrderedWith.081cd53d46d5db04.Core:Cpp", scope: null, file: !6, line: 16, type: !29, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !36)
 // CHECK:STDOUT: !36 = !{!37, !38}
 // CHECK:STDOUT: !37 = !DILocalVariable(arg: 1, scope: !35, type: !14)
 // CHECK:STDOUT: !38 = !DILocalVariable(arg: 2, scope: !35, type: !14)
 // CHECK:STDOUT: !39 = !DILocation(line: 16, column: 15, scope: !35)
-// CHECK:STDOUT: !40 = distinct !DISubprogram(name: "Greater", linkageName: "_CGreater:thunk:OrderedWith.76d9c95e44fa79ac.Core:Cpp", scope: null, file: !6, line: 12, type: !29, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !41)
+// CHECK:STDOUT: !40 = distinct !DISubprogram(name: "Greater", linkageName: "_CGreater:thunk:OrderedWith.081cd53d46d5db04.Core:Cpp", scope: null, file: !6, line: 12, type: !29, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !41)
 // CHECK:STDOUT: !41 = !{!42, !43}
 // CHECK:STDOUT: !42 = !DILocalVariable(arg: 1, scope: !40, type: !14)
 // CHECK:STDOUT: !43 = !DILocalVariable(arg: 2, scope: !40, type: !14)
 // CHECK:STDOUT: !44 = !DILocation(line: 12, column: 15, scope: !40)
-// CHECK:STDOUT: !45 = distinct !DISubprogram(name: "GreaterOrEquivalent", linkageName: "_CGreaterOrEquivalent:thunk:OrderedWith.76d9c95e44fa79ac.Core:Cpp", scope: null, file: !6, line: 20, type: !29, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !46)
+// CHECK:STDOUT: !45 = distinct !DISubprogram(name: "GreaterOrEquivalent", linkageName: "_CGreaterOrEquivalent:thunk:OrderedWith.081cd53d46d5db04.Core:Cpp", scope: null, file: !6, line: 20, type: !29, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !46)
 // CHECK:STDOUT: !46 = !{!47, !48}
 // CHECK:STDOUT: !47 = !DILocalVariable(arg: 1, scope: !45, type: !14)
 // CHECK:STDOUT: !48 = !DILocalVariable(arg: 2, scope: !45, type: !14)
 // CHECK:STDOUT: !49 = !DILocation(line: 20, column: 15, scope: !45)
-// CHECK:STDOUT: !50 = distinct !DISubprogram(name: "CheckOrderedWith", linkageName: "_CCheckOrderedWith.Main.cf2c934aa0200133", scope: null, file: !6, line: 26, type: !12, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !51)
+// CHECK:STDOUT: !50 = distinct !DISubprogram(name: "CheckOrderedWith", linkageName: "_CCheckOrderedWith.Main.9c69d70a853113d6", scope: null, file: !6, line: 26, type: !12, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !51)
 // CHECK:STDOUT: !51 = !{!52, !53}
 // CHECK:STDOUT: !52 = !DILocalVariable(arg: 1, scope: !50, type: !14)
 // CHECK:STDOUT: !53 = !DILocalVariable(arg: 2, scope: !50, type: !14)

toolchain/lower/testdata/interop/cpp/parameters.carbon

@@ -367,7 +367,7 @@ fn PassValueExpr(y: Cpp.Y) {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   %x.var = alloca [12 x i8], align 1, !dbg !14
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %x.var), !dbg !14
-// CHECK:STDOUT:   call void @"_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.e5c2acf57553d2f2"(ptr %x.var), !dbg !14
+// CHECK:STDOUT:   call void @"_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.1cc04ab0b0144e39"(ptr %x.var), !dbg !14
 // CHECK:STDOUT:   %.loc8_4.a = getelementptr inbounds nuw [12 x i8], ptr %x.var, i32 0, i32 0, !dbg !15
 // CHECK:STDOUT:   store i32 1, ptr %.loc8_4.a, align 4, !dbg !15
 // CHECK:STDOUT:   %.loc9_4.b = getelementptr inbounds nuw [12 x i8], ptr %x.var, i32 0, i32 4, !dbg !16
@@ -388,7 +388,7 @@ fn PassValueExpr(y: Cpp.Y) {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: alwaysinline nounwind
-// CHECK:STDOUT: define void @"_COp:thunk:Default.aebeffbfb3ea6f83.Core:X.Cpp"(ptr sret([12 x i8]) %return) #2 !dbg !23 {
+// CHECK:STDOUT: define void @"_COp:thunk:Default.73a6c13427a59137.Core:X.Cpp"(ptr sret([12 x i8]) %return) #2 !dbg !23 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   call void @_ZN1XC1Ev.carbon_thunk.(ptr %return), !dbg !28
 // CHECK:STDOUT:   ret void, !dbg !28
@@ -416,8 +416,8 @@ fn PassValueExpr(y: Cpp.Y) {
 // CHECK:STDOUT: declare void @llvm.lifetime.start.p0(ptr captures(none)) #4
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define linkonce_odr void @"_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.e5c2acf57553d2f2"(ptr sret([12 x i8]) %return) #0 !dbg !30 {
-// CHECK:STDOUT:   call void @"_COp:thunk:Default.aebeffbfb3ea6f83.Core:X.Cpp"(ptr %return), !dbg !32
+// CHECK:STDOUT: define linkonce_odr void @"_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.1cc04ab0b0144e39"(ptr sret([12 x i8]) %return) #0 !dbg !30 {
+// CHECK:STDOUT:   call void @"_COp:thunk:Default.73a6c13427a59137.Core:X.Cpp"(ptr %return), !dbg !32
 // CHECK:STDOUT:   ret void, !dbg !33
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
@@ -463,14 +463,14 @@ fn PassValueExpr(y: Cpp.Y) {
 // CHECK:STDOUT: !20 = !{!21, !21, i64 0}
 // CHECK:STDOUT: !21 = !{!"p1 _ZTS1X", !22, i64 0}
 // CHECK:STDOUT: !22 = !{!"any pointer", !9, i64 0}
-// CHECK:STDOUT: !23 = distinct !DISubprogram(name: "Op", linkageName: "_COp:thunk:Default.aebeffbfb3ea6f83.Core:X.Cpp", scope: null, file: !24, line: 2, type: !25, spFlags: DISPFlagDefinition, unit: !5)
+// CHECK:STDOUT: !23 = distinct !DISubprogram(name: "Op", linkageName: "_COp:thunk:Default.73a6c13427a59137.Core:X.Cpp", scope: null, file: !24, line: 2, type: !25, spFlags: DISPFlagDefinition, unit: !5)
 // CHECK:STDOUT: !24 = !DIFile(filename: "./struct.h", directory: "")
 // CHECK:STDOUT: !25 = !DISubroutineType(types: !26)
 // CHECK:STDOUT: !26 = !{!27}
 // CHECK:STDOUT: !27 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: null, size: 64)
 // CHECK:STDOUT: !28 = !DILocation(line: 2, column: 8, scope: !23)
 // CHECK:STDOUT: !29 = !{i64 0, i64 4, !7, i64 4, i64 4, !7, i64 8, i64 4, !7}
-// CHECK:STDOUT: !30 = distinct !DISubprogram(name: "Op", linkageName: "_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.e5c2acf57553d2f2", scope: null, file: !31, line: 9, type: !25, spFlags: DISPFlagDefinition, unit: !5)
+// CHECK:STDOUT: !30 = distinct !DISubprogram(name: "Op", linkageName: "_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.1cc04ab0b0144e39", scope: null, file: !31, line: 9, type: !25, spFlags: DISPFlagDefinition, unit: !5)
 // CHECK:STDOUT: !31 = !DIFile(filename: "min_prelude/parts/default.carbon", directory: "")
 // CHECK:STDOUT: !32 = !DILocation(line: 9, column: 28, scope: !30)
 // CHECK:STDOUT: !33 = !DILocation(line: 9, column: 21, scope: !30)

toolchain/lower/testdata/interop/cpp/pointer.carbon

@@ -218,25 +218,25 @@ fn Convert() {
 // CHECK:STDOUT: define void @_CPassNonnullPtr.Main(ptr %p) #0 !dbg !18 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   %.loc22_15.2.temp = alloca ptr, align 8, !dbg !21
-// CHECK:STDOUT:   %U.as_type.as.ImplicitAs.impl.Convert.call = call ptr @"_CConvert.6391a65a70757668:ImplicitAs.116c0b3f4fb552e2.Core.7ca8ed081f5d7ff7"(ptr %p), !dbg !21
+// CHECK:STDOUT:   %U.as_type.as.ImplicitAs.impl.Convert.call = call ptr @"_CConvert.6391a65a70757668:ImplicitAs.116c0b3f4fb552e2.Core.470500545f897853"(ptr %p), !dbg !21
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc22_15.2.temp), !dbg !21
 // CHECK:STDOUT:   store ptr %U.as_type.as.ImplicitAs.impl.Convert.call, ptr %.loc22_15.2.temp, align 8, !dbg !21
 // CHECK:STDOUT:   %.loc22_15.4 = load ptr, ptr %.loc22_15.2.temp, align 8, !dbg !21
 // CHECK:STDOUT:   call void @_Z7TakePtrP1C(ptr %.loc22_15.4), !dbg !22
-// CHECK:STDOUT:   call void @"_COp.357c5945ee623cad:core.Destroy.Core"(ptr %.loc22_15.2.temp), !dbg !21
+// CHECK:STDOUT:   call void @"_COp.f077811596b04c1e:core.Destroy.Core"(ptr %.loc22_15.2.temp), !dbg !21
 // CHECK:STDOUT:   ret void, !dbg !23
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: declare void @_Z7TakePtrP1C(ptr noundef) #1
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define weak_odr void @"_COp.35482251414d9bba:core.Destroy.Core"(ptr %self) #0 !dbg !24 {
+// CHECK:STDOUT: define weak_odr void @"_COp.b8799b2262fcbb9d:core.Destroy.Core"(ptr %self) #0 !dbg !24 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   ret void, !dbg !27
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define weak_odr void @"_COp.357c5945ee623cad:core.Destroy.Core"(ptr %self) #0 !dbg !28 {
+// CHECK:STDOUT: define weak_odr void @"_COp.f077811596b04c1e:core.Destroy.Core"(ptr %self) #0 !dbg !28 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   ret void, !dbg !31
 // CHECK:STDOUT: }
@@ -260,12 +260,12 @@ fn Convert() {
 // CHECK:STDOUT: define void @_CPassNonnullPtrWithThunk.Main(ptr %p) #0 !dbg !41 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   %.loc35_24.2.temp = alloca ptr, align 8, !dbg !44
-// CHECK:STDOUT:   %U.as_type.as.ImplicitAs.impl.Convert.call = call ptr @"_CConvert.6391a65a70757668:ImplicitAs.116c0b3f4fb552e2.Core.7ca8ed081f5d7ff7"(ptr %p), !dbg !44
+// CHECK:STDOUT:   %U.as_type.as.ImplicitAs.impl.Convert.call = call ptr @"_CConvert.6391a65a70757668:ImplicitAs.116c0b3f4fb552e2.Core.470500545f897853"(ptr %p), !dbg !44
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc35_24.2.temp), !dbg !44
 // CHECK:STDOUT:   store ptr %U.as_type.as.ImplicitAs.impl.Convert.call, ptr %.loc35_24.2.temp, align 8, !dbg !44
 // CHECK:STDOUT:   %.loc35_24.4 = load ptr, ptr %.loc35_24.2.temp, align 8, !dbg !44
 // CHECK:STDOUT:   call void @_Z16TakePtrWithThunkP1Ci.carbon_thunk._(ptr %.loc35_24.4), !dbg !45
-// CHECK:STDOUT:   call void @"_COp.357c5945ee623cad:core.Destroy.Core"(ptr %.loc35_24.2.temp), !dbg !44
+// CHECK:STDOUT:   call void @"_COp.f077811596b04c1e:core.Destroy.Core"(ptr %.loc35_24.2.temp), !dbg !44
 // CHECK:STDOUT:   ret void, !dbg !46
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
@@ -294,8 +294,8 @@ fn Convert() {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define linkonce_odr ptr @"_CConvert.6391a65a70757668:ImplicitAs.116c0b3f4fb552e2.Core.7ca8ed081f5d7ff7"(ptr %self) #0 !dbg !53 {
-// CHECK:STDOUT:   %1 = call ptr @"_CConvert.ba9a17e320476215:OptionalAs.7eef99cd03a74de4.Core.63998780806c7fd2"(ptr %self), !dbg !59
+// CHECK:STDOUT: define linkonce_odr ptr @"_CConvert.6391a65a70757668:ImplicitAs.116c0b3f4fb552e2.Core.470500545f897853"(ptr %self) #0 !dbg !53 {
+// CHECK:STDOUT:   %1 = call ptr @"_CConvert.ba9a17e320476215:OptionalAs.7eef99cd03a74de4.Core.20b091e87e8b790e"(ptr %self), !dbg !59
 // CHECK:STDOUT:   ret ptr %1, !dbg !60
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
@@ -303,25 +303,25 @@ fn Convert() {
 // CHECK:STDOUT: declare void @llvm.lifetime.start.p0(ptr captures(none)) #3
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define linkonce_odr ptr @"_CConvert.ba9a17e320476215:OptionalAs.7eef99cd03a74de4.Core.63998780806c7fd2"(ptr %self) #0 !dbg !61 {
-// CHECK:STDOUT:   %1 = call ptr @_CSome.Optional.Core.63998780806c7fd2(ptr %self), !dbg !64
+// CHECK:STDOUT: define linkonce_odr ptr @"_CConvert.ba9a17e320476215:OptionalAs.7eef99cd03a74de4.Core.20b091e87e8b790e"(ptr %self) #0 !dbg !61 {
+// CHECK:STDOUT:   %1 = call ptr @_CSome.Optional.Core.20b091e87e8b790e(ptr %self), !dbg !64
 // CHECK:STDOUT:   ret ptr %1, !dbg !65
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define linkonce_odr ptr @_CSome.Optional.Core.63998780806c7fd2(ptr %value) #0 !dbg !66 {
-// CHECK:STDOUT:   %1 = call ptr @"_CSome.e8f8f92d3d08d149:OptionalStorage.Core.908e8f868f225690"(ptr %value), !dbg !69
+// CHECK:STDOUT: define linkonce_odr ptr @_CSome.Optional.Core.20b091e87e8b790e(ptr %value) #0 !dbg !66 {
+// CHECK:STDOUT:   %1 = call ptr @"_CSome.e8f8f92d3d08d149:OptionalStorage.Core.b88531aa40419bf2"(ptr %value), !dbg !69
 // CHECK:STDOUT:   ret ptr %1, !dbg !70
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define linkonce_odr ptr @"_CSome.e8f8f92d3d08d149:OptionalStorage.Core.908e8f868f225690"(ptr %self) #0 !dbg !71 {
+// CHECK:STDOUT: define linkonce_odr ptr @"_CSome.e8f8f92d3d08d149:OptionalStorage.Core.b88531aa40419bf2"(ptr %self) #0 !dbg !71 {
 // CHECK:STDOUT:   %1 = alloca ptr, align 8, !dbg !74
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %1), !dbg !74
 // CHECK:STDOUT:   store ptr poison, ptr %1, align 8, !dbg !74
 // CHECK:STDOUT:   store ptr %self, ptr %1, align 8, !dbg !75
 // CHECK:STDOUT:   %2 = load ptr, ptr %1, align 8, !dbg !76
-// CHECK:STDOUT:   call void @"_COp.35482251414d9bba:core.Destroy.Core"(ptr %1), !dbg !74
+// CHECK:STDOUT:   call void @"_COp.b8799b2262fcbb9d:core.Destroy.Core"(ptr %1), !dbg !74
 // CHECK:STDOUT:   ret ptr %2, !dbg !77
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
@@ -330,7 +330,7 @@ fn Convert() {
 // CHECK:STDOUT: declare noundef ptr @_Z18ReturnPtrWithThunki(i32 noundef) #1
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; uselistorder directives
-// CHECK:STDOUT: uselistorder ptr @"_CConvert.6391a65a70757668:ImplicitAs.116c0b3f4fb552e2.Core.7ca8ed081f5d7ff7", { 1, 0 }
+// CHECK:STDOUT: uselistorder ptr @"_CConvert.6391a65a70757668:ImplicitAs.116c0b3f4fb552e2.Core.470500545f897853", { 1, 0 }
 // CHECK:STDOUT: uselistorder ptr @llvm.lifetime.start.p0, { 0, 2, 1 }
 // CHECK:STDOUT:
 // CHECK:STDOUT: attributes #0 = { nounwind }
@@ -366,11 +366,11 @@ fn Convert() {
 // CHECK:STDOUT: !21 = !DILocation(line: 22, column: 15, scope: !18)
 // CHECK:STDOUT: !22 = !DILocation(line: 22, column: 3, scope: !18)
 // CHECK:STDOUT: !23 = !DILocation(line: 19, column: 1, scope: !18)
-// CHECK:STDOUT: !24 = distinct !DISubprogram(name: "Op", linkageName: "_COp.35482251414d9bba:core.Destroy.Core", scope: null, file: !6, line: 22, type: !12, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !25)
+// CHECK:STDOUT: !24 = distinct !DISubprogram(name: "Op", linkageName: "_COp.b8799b2262fcbb9d:core.Destroy.Core", scope: null, file: !6, line: 22, type: !12, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !25)
 // CHECK:STDOUT: !25 = !{!26}
 // CHECK:STDOUT: !26 = !DILocalVariable(arg: 1, scope: !24, type: !14)
 // CHECK:STDOUT: !27 = !DILocation(line: 22, column: 15, scope: !24)
-// CHECK:STDOUT: !28 = distinct !DISubprogram(name: "Op", linkageName: "_COp.357c5945ee623cad:core.Destroy.Core", scope: null, file: !6, line: 22, type: !12, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !29)
+// CHECK:STDOUT: !28 = distinct !DISubprogram(name: "Op", linkageName: "_COp.f077811596b04c1e:core.Destroy.Core", scope: null, file: !6, line: 22, type: !12, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !29)
 // CHECK:STDOUT: !29 = !{!30}
 // CHECK:STDOUT: !30 = !DILocalVariable(arg: 1, scope: !28, type: !14)
 // CHECK:STDOUT: !31 = !DILocation(line: 22, column: 15, scope: !28)
@@ -395,7 +395,7 @@ fn Convert() {
 // CHECK:STDOUT: !50 = distinct !DISubprogram(name: "ReturnPtrWithThunk", linkageName: "_CReturnPtrWithThunk.Main", scope: null, file: !6, line: 38, type: !33, spFlags: DISPFlagDefinition, unit: !5)
 // CHECK:STDOUT: !51 = !DILocation(line: 39, column: 10, scope: !50)
 // CHECK:STDOUT: !52 = !DILocation(line: 39, column: 3, scope: !50)
-// CHECK:STDOUT: !53 = distinct !DISubprogram(name: "Convert", linkageName: "_CConvert.6391a65a70757668:ImplicitAs.116c0b3f4fb552e2.Core.7ca8ed081f5d7ff7", scope: null, file: !54, line: 105, type: !55, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !57)
+// CHECK:STDOUT: !53 = distinct !DISubprogram(name: "Convert", linkageName: "_CConvert.6391a65a70757668:ImplicitAs.116c0b3f4fb552e2.Core.470500545f897853", scope: null, file: !54, line: 105, type: !55, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !57)
 // CHECK:STDOUT: !54 = !DIFile(filename: "{{.*}}/prelude/types/optional.carbon", directory: "")
 // CHECK:STDOUT: !55 = !DISubroutineType(types: !56)
 // CHECK:STDOUT: !56 = !{!14, !14}
@@ -403,17 +403,17 @@ fn Convert() {
 // CHECK:STDOUT: !58 = !DILocalVariable(arg: 1, scope: !53, type: !14)
 // CHECK:STDOUT: !59 = !DILocation(line: 106, column: 12, scope: !53)
 // CHECK:STDOUT: !60 = !DILocation(line: 106, column: 5, scope: !53)
-// CHECK:STDOUT: !61 = distinct !DISubprogram(name: "Convert", linkageName: "_CConvert.ba9a17e320476215:OptionalAs.7eef99cd03a74de4.Core.63998780806c7fd2", scope: null, file: !54, line: 80, type: !55, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !62)
+// CHECK:STDOUT: !61 = distinct !DISubprogram(name: "Convert", linkageName: "_CConvert.ba9a17e320476215:OptionalAs.7eef99cd03a74de4.Core.20b091e87e8b790e", scope: null, file: !54, line: 80, type: !55, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !62)
 // CHECK:STDOUT: !62 = !{!63}
 // CHECK:STDOUT: !63 = !DILocalVariable(arg: 1, scope: !61, type: !14)
 // CHECK:STDOUT: !64 = !DILocation(line: 81, column: 12, scope: !61)
 // CHECK:STDOUT: !65 = !DILocation(line: 81, column: 5, scope: !61)
-// CHECK:STDOUT: !66 = distinct !DISubprogram(name: "Some", linkageName: "_CSome.Optional.Core.63998780806c7fd2", scope: null, file: !54, line: 33, type: !55, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !67)
+// CHECK:STDOUT: !66 = distinct !DISubprogram(name: "Some", linkageName: "_CSome.Optional.Core.20b091e87e8b790e", scope: null, file: !54, line: 33, type: !55, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !67)
 // CHECK:STDOUT: !67 = !{!68}
 // CHECK:STDOUT: !68 = !DILocalVariable(arg: 1, scope: !66, type: !14)
 // CHECK:STDOUT: !69 = !DILocation(line: 34, column: 12, scope: !66)
 // CHECK:STDOUT: !70 = !DILocation(line: 34, column: 5, scope: !66)
-// CHECK:STDOUT: !71 = distinct !DISubprogram(name: "Some", linkageName: "_CSome.e8f8f92d3d08d149:OptionalStorage.Core.908e8f868f225690", scope: null, file: !54, line: 166, type: !55, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !72)
+// CHECK:STDOUT: !71 = distinct !DISubprogram(name: "Some", linkageName: "_CSome.e8f8f92d3d08d149:OptionalStorage.Core.b88531aa40419bf2", scope: null, file: !54, line: 166, type: !55, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !72)
 // CHECK:STDOUT: !72 = !{!73}
 // CHECK:STDOUT: !73 = !DILocalVariable(arg: 1, scope: !71, type: !14)
 // CHECK:STDOUT: !74 = !DILocation(line: 167, column: 14, scope: !71)
@@ -434,13 +434,13 @@ fn Convert() {
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc9_21.1.temp), !dbg !14
 // CHECK:STDOUT:   store ptr %make.call, ptr %.loc9_21.1.temp, align 8, !dbg !14
 // CHECK:STDOUT:   %.loc9_21.3 = load ptr, ptr %.loc9_21.1.temp, align 8, !dbg !14
-// CHECK:STDOUT:   %U.as_type.as.ImplicitAs.impl.Convert.call = call ptr @"_CConvert.6391a65a70757668:ImplicitAs.116c0b3f4fb552e2.Core.db0c0c062ccbeee2"(ptr %.loc9_21.3), !dbg !14
+// CHECK:STDOUT:   %U.as_type.as.ImplicitAs.impl.Convert.call = call ptr @"_CConvert.6391a65a70757668:ImplicitAs.116c0b3f4fb552e2.Core.e9a39e86438b926b"(ptr %.loc9_21.3), !dbg !14
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc9_21.5.temp), !dbg !14
 // CHECK:STDOUT:   store ptr %U.as_type.as.ImplicitAs.impl.Convert.call, ptr %.loc9_21.5.temp, align 8, !dbg !14
 // CHECK:STDOUT:   %.loc9_21.7 = load ptr, ptr %.loc9_21.5.temp, align 8, !dbg !14
 // CHECK:STDOUT:   call void @_Z4takePK1C(ptr %.loc9_21.7), !dbg !15
-// CHECK:STDOUT:   call void @"_COp.70b543b9054a214c:core.Destroy.Core"(ptr %.loc9_21.5.temp), !dbg !14
-// CHECK:STDOUT:   call void @"_COp.3c4756f6f67440bc:core.Destroy.Core"(ptr %.loc9_21.1.temp), !dbg !14
+// CHECK:STDOUT:   call void @"_COp.269ea07577c64bb2:core.Destroy.Core"(ptr %.loc9_21.5.temp), !dbg !14
+// CHECK:STDOUT:   call void @"_COp.d665875966a4162d:core.Destroy.Core"(ptr %.loc9_21.1.temp), !dbg !14
 // CHECK:STDOUT:   ret void, !dbg !16
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
@@ -449,25 +449,25 @@ fn Convert() {
 // CHECK:STDOUT: declare void @_Z4takePK1C(ptr noundef) #1
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define weak_odr void @"_COp.3c6e3be6b375f0fe:core.Destroy.Core"(ptr %self) #0 !dbg !17 {
+// CHECK:STDOUT: define weak_odr void @"_COp.4038455b5b2635f6:core.Destroy.Core"(ptr %self) #0 !dbg !17 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   ret void, !dbg !23
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define weak_odr void @"_COp.70b543b9054a214c:core.Destroy.Core"(ptr %self) #0 !dbg !24 {
+// CHECK:STDOUT: define weak_odr void @"_COp.269ea07577c64bb2:core.Destroy.Core"(ptr %self) #0 !dbg !24 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   ret void, !dbg !27
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define weak_odr void @"_COp.35482251414d9bba:core.Destroy.Core"(ptr %self) #0 !dbg !28 {
+// CHECK:STDOUT: define weak_odr void @"_COp.b8799b2262fcbb9d:core.Destroy.Core"(ptr %self) #0 !dbg !28 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   ret void, !dbg !31
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define weak_odr void @"_COp.3c4756f6f67440bc:core.Destroy.Core"(ptr %self) #0 !dbg !32 {
+// CHECK:STDOUT: define weak_odr void @"_COp.d665875966a4162d:core.Destroy.Core"(ptr %self) #0 !dbg !32 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   ret void, !dbg !35
 // CHECK:STDOUT: }
@@ -476,77 +476,77 @@ fn Convert() {
 // CHECK:STDOUT: declare void @llvm.lifetime.start.p0(ptr captures(none)) #2
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define linkonce_odr ptr @"_CConvert.6391a65a70757668:ImplicitAs.116c0b3f4fb552e2.Core.db0c0c062ccbeee2"(ptr %self) #0 !dbg !36 {
-// CHECK:STDOUT:   %1 = call ptr @"_CConvert.Optional.5dca1548b0a7c023.Core:OptionalAs.f5e7d4305ac1f327.Core.dcb11ca5ddf1633f"(ptr %self), !dbg !42
+// CHECK:STDOUT: define linkonce_odr ptr @"_CConvert.6391a65a70757668:ImplicitAs.116c0b3f4fb552e2.Core.e9a39e86438b926b"(ptr %self) #0 !dbg !36 {
+// CHECK:STDOUT:   %1 = call ptr @"_CConvert.Optional.5dca1548b0a7c023.Core:OptionalAs.f5e7d4305ac1f327.Core.c757ec210d8fc687"(ptr %self), !dbg !42
 // CHECK:STDOUT:   ret ptr %1, !dbg !43
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define linkonce_odr ptr @"_CConvert.Optional.5dca1548b0a7c023.Core:OptionalAs.f5e7d4305ac1f327.Core.dcb11ca5ddf1633f"(ptr %self) #0 !dbg !44 {
+// CHECK:STDOUT: define linkonce_odr ptr @"_CConvert.Optional.5dca1548b0a7c023.Core:OptionalAs.f5e7d4305ac1f327.Core.c757ec210d8fc687"(ptr %self) #0 !dbg !44 {
 // CHECK:STDOUT:   %temp = alloca ptr, align 8, !dbg !47
 // CHECK:STDOUT:   %temp1 = alloca ptr, align 8, !dbg !47
-// CHECK:STDOUT:   %1 = call i1 @_CHasValue.Optional.Core.2b3974338accec9e(ptr %self), !dbg !48
+// CHECK:STDOUT:   %1 = call i1 @_CHasValue.Optional.Core.e8736bdbdea23abc(ptr %self), !dbg !48
 // CHECK:STDOUT:   br i1 %1, label %2, label %7, !dbg !49
 // CHECK:STDOUT:
 // CHECK:STDOUT: 2:                                                ; preds = %0
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %temp), !dbg !47
-// CHECK:STDOUT:   %3 = call ptr @_CGet.Optional.Core.2b3974338accec9e(ptr %self), !dbg !47
+// CHECK:STDOUT:   %3 = call ptr @_CGet.Optional.Core.e8736bdbdea23abc(ptr %self), !dbg !47
 // CHECK:STDOUT:   store ptr %3, ptr %temp, align 8, !dbg !47
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %temp1), !dbg !47
 // CHECK:STDOUT:   %4 = load ptr, ptr %temp, align 8, !dbg !47
 // CHECK:STDOUT:   store ptr %4, ptr %temp1, align 8, !dbg !47
 // CHECK:STDOUT:   %5 = load ptr, ptr %temp1, align 8, !dbg !47
-// CHECK:STDOUT:   %6 = call ptr @_CSome.Optional.Core.428663f04d56e65c(ptr %5), !dbg !50
+// CHECK:STDOUT:   %6 = call ptr @_CSome.Optional.Core.cc4dde828948b100(ptr %5), !dbg !50
 // CHECK:STDOUT:   ret ptr %6, !dbg !51
 // CHECK:STDOUT:
 // CHECK:STDOUT: 7:                                                ; preds = %0
-// CHECK:STDOUT:   %8 = call ptr @_CNone.Optional.Core.428663f04d56e65c(), !dbg !52
+// CHECK:STDOUT:   %8 = call ptr @_CNone.Optional.Core.cc4dde828948b100(), !dbg !52
 // CHECK:STDOUT:   ret ptr %8, !dbg !53
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define linkonce_odr i1 @_CHasValue.Optional.Core.2b3974338accec9e(ptr %self) #0 !dbg !54 {
-// CHECK:STDOUT:   %1 = call i1 @"_CHas.e8f8f92d3d08d149:OptionalStorage.Core.908e8f868f225690"(ptr %self), !dbg !57
+// CHECK:STDOUT: define linkonce_odr i1 @_CHasValue.Optional.Core.e8736bdbdea23abc(ptr %self) #0 !dbg !54 {
+// CHECK:STDOUT:   %1 = call i1 @"_CHas.e8f8f92d3d08d149:OptionalStorage.Core.b88531aa40419bf2"(ptr %self), !dbg !57
 // CHECK:STDOUT:   ret i1 %1, !dbg !58
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define linkonce_odr ptr @_CGet.Optional.Core.2b3974338accec9e(ptr %self) #0 !dbg !59 {
-// CHECK:STDOUT:   %1 = call ptr @"_CGet.e8f8f92d3d08d149:OptionalStorage.Core.908e8f868f225690"(ptr %self), !dbg !62
+// CHECK:STDOUT: define linkonce_odr ptr @_CGet.Optional.Core.e8736bdbdea23abc(ptr %self) #0 !dbg !59 {
+// CHECK:STDOUT:   %1 = call ptr @"_CGet.e8f8f92d3d08d149:OptionalStorage.Core.b88531aa40419bf2"(ptr %self), !dbg !62
 // CHECK:STDOUT:   ret ptr %1, !dbg !63
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define linkonce_odr ptr @_CSome.Optional.Core.428663f04d56e65c(ptr %value) #0 !dbg !64 {
-// CHECK:STDOUT:   %1 = call ptr @"_CSome.e8f8f92d3d08d149:OptionalStorage.Core.11944b9073985c4a"(ptr %value), !dbg !67
+// CHECK:STDOUT: define linkonce_odr ptr @_CSome.Optional.Core.cc4dde828948b100(ptr %value) #0 !dbg !64 {
+// CHECK:STDOUT:   %1 = call ptr @"_CSome.e8f8f92d3d08d149:OptionalStorage.Core.0e66b20f8d4f0663"(ptr %value), !dbg !67
 // CHECK:STDOUT:   ret ptr %1, !dbg !68
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define linkonce_odr ptr @_CNone.Optional.Core.428663f04d56e65c() #0 !dbg !69 {
+// CHECK:STDOUT: define linkonce_odr ptr @_CNone.Optional.Core.cc4dde828948b100() #0 !dbg !69 {
 // CHECK:STDOUT:   ret ptr null, !dbg !72
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define linkonce_odr i1 @"_CHas.e8f8f92d3d08d149:OptionalStorage.Core.908e8f868f225690"(ptr %value) #0 !dbg !73 {
+// CHECK:STDOUT: define linkonce_odr i1 @"_CHas.e8f8f92d3d08d149:OptionalStorage.Core.b88531aa40419bf2"(ptr %value) #0 !dbg !73 {
 // CHECK:STDOUT:   %1 = icmp eq ptr %value, null, !dbg !76
 // CHECK:STDOUT:   %2 = xor i1 %1, true, !dbg !77
 // CHECK:STDOUT:   ret i1 %2, !dbg !78
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define linkonce_odr ptr @"_CGet.e8f8f92d3d08d149:OptionalStorage.Core.908e8f868f225690"(ptr %value) #0 !dbg !79 {
+// CHECK:STDOUT: define linkonce_odr ptr @"_CGet.e8f8f92d3d08d149:OptionalStorage.Core.b88531aa40419bf2"(ptr %value) #0 !dbg !79 {
 // CHECK:STDOUT:   ret ptr %value, !dbg !82
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define linkonce_odr ptr @"_CSome.e8f8f92d3d08d149:OptionalStorage.Core.11944b9073985c4a"(ptr %self) #0 !dbg !83 {
+// CHECK:STDOUT: define linkonce_odr ptr @"_CSome.e8f8f92d3d08d149:OptionalStorage.Core.0e66b20f8d4f0663"(ptr %self) #0 !dbg !83 {
 // CHECK:STDOUT:   %1 = alloca ptr, align 8, !dbg !86
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %1), !dbg !86
 // CHECK:STDOUT:   store ptr poison, ptr %1, align 8, !dbg !86
 // CHECK:STDOUT:   store ptr %self, ptr %1, align 8, !dbg !87
 // CHECK:STDOUT:   %2 = load ptr, ptr %1, align 8, !dbg !88
-// CHECK:STDOUT:   call void @"_COp.3c6e3be6b375f0fe:core.Destroy.Core"(ptr %1), !dbg !86
+// CHECK:STDOUT:   call void @"_COp.4038455b5b2635f6:core.Destroy.Core"(ptr %1), !dbg !86
 // CHECK:STDOUT:   ret ptr %2, !dbg !89
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
@@ -578,26 +578,26 @@ fn Convert() {
 // CHECK:STDOUT: !14 = !DILocation(line: 9, column: 12, scope: !11)
 // CHECK:STDOUT: !15 = !DILocation(line: 9, column: 3, scope: !11)
 // CHECK:STDOUT: !16 = !DILocation(line: 8, column: 1, scope: !11)
-// CHECK:STDOUT: !17 = distinct !DISubprogram(name: "Op", linkageName: "_COp.3c6e3be6b375f0fe:core.Destroy.Core", scope: null, file: !6, line: 9, type: !18, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !21)
+// CHECK:STDOUT: !17 = distinct !DISubprogram(name: "Op", linkageName: "_COp.4038455b5b2635f6:core.Destroy.Core", scope: null, file: !6, line: 9, type: !18, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !21)
 // CHECK:STDOUT: !18 = !DISubroutineType(types: !19)
 // CHECK:STDOUT: !19 = !{null, !20}
 // CHECK:STDOUT: !20 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: null, size: 64)
 // CHECK:STDOUT: !21 = !{!22}
 // CHECK:STDOUT: !22 = !DILocalVariable(arg: 1, scope: !17, type: !20)
 // CHECK:STDOUT: !23 = !DILocation(line: 9, column: 12, scope: !17)
-// CHECK:STDOUT: !24 = distinct !DISubprogram(name: "Op", linkageName: "_COp.70b543b9054a214c:core.Destroy.Core", scope: null, file: !6, line: 9, type: !18, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !25)
+// CHECK:STDOUT: !24 = distinct !DISubprogram(name: "Op", linkageName: "_COp.269ea07577c64bb2:core.Destroy.Core", scope: null, file: !6, line: 9, type: !18, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !25)
 // CHECK:STDOUT: !25 = !{!26}
 // CHECK:STDOUT: !26 = !DILocalVariable(arg: 1, scope: !24, type: !20)
 // CHECK:STDOUT: !27 = !DILocation(line: 9, column: 12, scope: !24)
-// CHECK:STDOUT: !28 = distinct !DISubprogram(name: "Op", linkageName: "_COp.35482251414d9bba:core.Destroy.Core", scope: null, file: !6, line: 9, type: !18, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !29)
+// CHECK:STDOUT: !28 = distinct !DISubprogram(name: "Op", linkageName: "_COp.b8799b2262fcbb9d:core.Destroy.Core", scope: null, file: !6, line: 9, type: !18, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !29)
 // CHECK:STDOUT: !29 = !{!30}
 // CHECK:STDOUT: !30 = !DILocalVariable(arg: 1, scope: !28, type: !20)
 // CHECK:STDOUT: !31 = !DILocation(line: 9, column: 12, scope: !28)
-// CHECK:STDOUT: !32 = distinct !DISubprogram(name: "Op", linkageName: "_COp.3c4756f6f67440bc:core.Destroy.Core", scope: null, file: !6, line: 9, type: !18, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !33)
+// CHECK:STDOUT: !32 = distinct !DISubprogram(name: "Op", linkageName: "_COp.d665875966a4162d:core.Destroy.Core", scope: null, file: !6, line: 9, type: !18, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !33)
 // CHECK:STDOUT: !33 = !{!34}
 // CHECK:STDOUT: !34 = !DILocalVariable(arg: 1, scope: !32, type: !20)
 // CHECK:STDOUT: !35 = !DILocation(line: 9, column: 12, scope: !32)
-// CHECK:STDOUT: !36 = distinct !DISubprogram(name: "Convert", linkageName: "_CConvert.6391a65a70757668:ImplicitAs.116c0b3f4fb552e2.Core.db0c0c062ccbeee2", scope: null, file: !37, line: 105, type: !38, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !40)
+// CHECK:STDOUT: !36 = distinct !DISubprogram(name: "Convert", linkageName: "_CConvert.6391a65a70757668:ImplicitAs.116c0b3f4fb552e2.Core.e9a39e86438b926b", scope: null, file: !37, line: 105, type: !38, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !40)
 // CHECK:STDOUT: !37 = !DIFile(filename: "{{.*}}/prelude/types/optional.carbon", directory: "")
 // CHECK:STDOUT: !38 = !DISubroutineType(types: !39)
 // CHECK:STDOUT: !39 = !{!20, !20}
@@ -605,7 +605,7 @@ fn Convert() {
 // CHECK:STDOUT: !41 = !DILocalVariable(arg: 1, scope: !36, type: !20)
 // CHECK:STDOUT: !42 = !DILocation(line: 106, column: 12, scope: !36)
 // CHECK:STDOUT: !43 = !DILocation(line: 106, column: 5, scope: !36)
-// CHECK:STDOUT: !44 = distinct !DISubprogram(name: "Convert", linkageName: "_CConvert.Optional.5dca1548b0a7c023.Core:OptionalAs.f5e7d4305ac1f327.Core.dcb11ca5ddf1633f", scope: null, file: !37, line: 95, type: !38, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !45)
+// CHECK:STDOUT: !44 = distinct !DISubprogram(name: "Convert", linkageName: "_CConvert.Optional.5dca1548b0a7c023.Core:OptionalAs.f5e7d4305ac1f327.Core.c757ec210d8fc687", scope: null, file: !37, line: 95, type: !38, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !45)
 // CHECK:STDOUT: !45 = !{!46}
 // CHECK:STDOUT: !46 = !DILocalVariable(arg: 1, scope: !44, type: !20)
 // CHECK:STDOUT: !47 = !DILocation(line: 97, column: 31, scope: !44)
@@ -615,36 +615,36 @@ fn Convert() {
 // CHECK:STDOUT: !51 = !DILocation(line: 97, column: 7, scope: !44)
 // CHECK:STDOUT: !52 = !DILocation(line: 99, column: 12, scope: !44)
 // CHECK:STDOUT: !53 = !DILocation(line: 99, column: 5, scope: !44)
-// CHECK:STDOUT: !54 = distinct !DISubprogram(name: "HasValue", linkageName: "_CHasValue.Optional.Core.2b3974338accec9e", scope: null, file: !37, line: 36, type: !38, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !55)
+// CHECK:STDOUT: !54 = distinct !DISubprogram(name: "HasValue", linkageName: "_CHasValue.Optional.Core.e8736bdbdea23abc", scope: null, file: !37, line: 36, type: !38, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !55)
 // CHECK:STDOUT: !55 = !{!56}
 // CHECK:STDOUT: !56 = !DILocalVariable(arg: 1, scope: !54, type: !20)
 // CHECK:STDOUT: !57 = !DILocation(line: 37, column: 12, scope: !54)
 // CHECK:STDOUT: !58 = !DILocation(line: 37, column: 5, scope: !54)
-// CHECK:STDOUT: !59 = distinct !DISubprogram(name: "Get", linkageName: "_CGet.Optional.Core.2b3974338accec9e", scope: null, file: !37, line: 39, type: !38, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !60)
+// CHECK:STDOUT: !59 = distinct !DISubprogram(name: "Get", linkageName: "_CGet.Optional.Core.e8736bdbdea23abc", scope: null, file: !37, line: 39, type: !38, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !60)
 // CHECK:STDOUT: !60 = !{!61}
 // CHECK:STDOUT: !61 = !DILocalVariable(arg: 1, scope: !59, type: !20)
 // CHECK:STDOUT: !62 = !DILocation(line: 40, column: 12, scope: !59)
 // CHECK:STDOUT: !63 = !DILocation(line: 40, column: 5, scope: !59)
-// CHECK:STDOUT: !64 = distinct !DISubprogram(name: "Some", linkageName: "_CSome.Optional.Core.428663f04d56e65c", scope: null, file: !37, line: 33, type: !38, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !65)
+// CHECK:STDOUT: !64 = distinct !DISubprogram(name: "Some", linkageName: "_CSome.Optional.Core.cc4dde828948b100", scope: null, file: !37, line: 33, type: !38, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !65)
 // CHECK:STDOUT: !65 = !{!66}
 // CHECK:STDOUT: !66 = !DILocalVariable(arg: 1, scope: !64, type: !20)
 // CHECK:STDOUT: !67 = !DILocation(line: 34, column: 12, scope: !64)
 // CHECK:STDOUT: !68 = !DILocation(line: 34, column: 5, scope: !64)
-// CHECK:STDOUT: !69 = distinct !DISubprogram(name: "None", linkageName: "_CNone.Optional.Core.428663f04d56e65c", scope: null, file: !37, line: 30, type: !70, spFlags: DISPFlagDefinition, unit: !5)
+// CHECK:STDOUT: !69 = distinct !DISubprogram(name: "None", linkageName: "_CNone.Optional.Core.cc4dde828948b100", scope: null, file: !37, line: 30, type: !70, spFlags: DISPFlagDefinition, unit: !5)
 // CHECK:STDOUT: !70 = !DISubroutineType(types: !71)
 // CHECK:STDOUT: !71 = !{!20}
 // CHECK:STDOUT: !72 = !DILocation(line: 31, column: 5, scope: !69)
-// CHECK:STDOUT: !73 = distinct !DISubprogram(name: "Has", linkageName: "_CHas.e8f8f92d3d08d149:OptionalStorage.Core.908e8f868f225690", scope: null, file: !37, line: 172, type: !38, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !74)
+// CHECK:STDOUT: !73 = distinct !DISubprogram(name: "Has", linkageName: "_CHas.e8f8f92d3d08d149:OptionalStorage.Core.b88531aa40419bf2", scope: null, file: !37, line: 172, type: !38, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !74)
 // CHECK:STDOUT: !74 = !{!75}
 // CHECK:STDOUT: !75 = !DILocalVariable(arg: 1, scope: !73, type: !20)
 // CHECK:STDOUT: !76 = !DILocation(line: 173, column: 16, scope: !73)
 // CHECK:STDOUT: !77 = !DILocation(line: 173, column: 12, scope: !73)
 // CHECK:STDOUT: !78 = !DILocation(line: 173, column: 5, scope: !73)
-// CHECK:STDOUT: !79 = distinct !DISubprogram(name: "Get", linkageName: "_CGet.e8f8f92d3d08d149:OptionalStorage.Core.908e8f868f225690", scope: null, file: !37, line: 175, type: !38, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !80)
+// CHECK:STDOUT: !79 = distinct !DISubprogram(name: "Get", linkageName: "_CGet.e8f8f92d3d08d149:OptionalStorage.Core.b88531aa40419bf2", scope: null, file: !37, line: 175, type: !38, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !80)
 // CHECK:STDOUT: !80 = !{!81}
 // CHECK:STDOUT: !81 = !DILocalVariable(arg: 1, scope: !79, type: !20)
 // CHECK:STDOUT: !82 = !DILocation(line: 176, column: 5, scope: !79)
-// CHECK:STDOUT: !83 = distinct !DISubprogram(name: "Some", linkageName: "_CSome.e8f8f92d3d08d149:OptionalStorage.Core.11944b9073985c4a", scope: null, file: !37, line: 166, type: !38, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !84)
+// CHECK:STDOUT: !83 = distinct !DISubprogram(name: "Some", linkageName: "_CSome.e8f8f92d3d08d149:OptionalStorage.Core.0e66b20f8d4f0663", scope: null, file: !37, line: 166, type: !38, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !84)
 // CHECK:STDOUT: !84 = !{!85}
 // CHECK:STDOUT: !85 = !DILocalVariable(arg: 1, scope: !83, type: !20)
 // CHECK:STDOUT: !86 = !DILocation(line: 167, column: 14, scope: !83)

toolchain/lower/testdata/interop/cpp/reference.carbon

@@ -144,7 +144,7 @@ fn GetRefs() {
 // CHECK:STDOUT:   %_.var.2 = alloca i32, align 4, !dbg !17
 // CHECK:STDOUT:   %.loc25_23.2.temp = alloca i32, align 4, !dbg !18
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %c.var), !dbg !14
-// CHECK:STDOUT:   call void @"_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.2603c91dd66a1dca"(ptr %c.var), !dbg !14
+// CHECK:STDOUT:   call void @"_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.4fdc745d4b6d0e3c"(ptr %c.var), !dbg !14
 // CHECK:STDOUT:   call void @_Z8TakeCRefR1C(ptr %c.var), !dbg !19
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var.1), !dbg !15
 // CHECK:STDOUT:   call void @llvm.memcpy.p0.p0.i64(ptr align 1 %_.var.1, ptr align 1 @C.val.loc19_20, i64 0, i1 false), !dbg !15
@@ -176,7 +176,7 @@ fn GetRefs() {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: alwaysinline nounwind
-// CHECK:STDOUT: define void @"_COp:thunk:Default.5648bcc2d6c775b7.Core:C.Cpp"(ptr sret({}) %return) #2 !dbg !29 {
+// CHECK:STDOUT: define void @"_COp:thunk:Default.08e786f435a99766.Core:C.Cpp"(ptr sret({}) %return) #2 !dbg !29 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   call void @_ZN1CC1Ev.carbon_thunk.(ptr %return), !dbg !33
 // CHECK:STDOUT:   ret void, !dbg !33
@@ -236,8 +236,8 @@ fn GetRefs() {
 // CHECK:STDOUT: declare void @llvm.lifetime.start.p0(ptr captures(none)) #5
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define linkonce_odr void @"_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.2603c91dd66a1dca"(ptr sret({}) %return) #0 !dbg !43 {
-// CHECK:STDOUT:   call void @"_COp:thunk:Default.5648bcc2d6c775b7.Core:C.Cpp"(ptr %return), !dbg !45
+// CHECK:STDOUT: define linkonce_odr void @"_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.4fdc745d4b6d0e3c"(ptr sret({}) %return) #0 !dbg !43 {
+// CHECK:STDOUT:   call void @"_COp:thunk:Default.08e786f435a99766.Core:C.Cpp"(ptr %return), !dbg !45
 // CHECK:STDOUT:   ret void, !dbg !46
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
@@ -296,7 +296,7 @@ fn GetRefs() {
 // CHECK:STDOUT: !26 = !{!27, !27, i64 0}
 // CHECK:STDOUT: !27 = !{!"p1 _ZTS1C", !28, i64 0}
 // CHECK:STDOUT: !28 = !{!"any pointer", !9, i64 0}
-// CHECK:STDOUT: !29 = distinct !DISubprogram(name: "Op", linkageName: "_COp:thunk:Default.5648bcc2d6c775b7.Core:C.Cpp", scope: null, file: !6, line: 5, type: !30, spFlags: DISPFlagDefinition, unit: !5)
+// CHECK:STDOUT: !29 = distinct !DISubprogram(name: "Op", linkageName: "_COp:thunk:Default.08e786f435a99766.Core:C.Cpp", scope: null, file: !6, line: 5, type: !30, spFlags: DISPFlagDefinition, unit: !5)
 // CHECK:STDOUT: !30 = !DISubroutineType(types: !31)
 // CHECK:STDOUT: !31 = !{!32}
 // CHECK:STDOUT: !32 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: null, size: 64)
@@ -310,7 +310,7 @@ fn GetRefs() {
 // CHECK:STDOUT: !40 = !{!41}
 // CHECK:STDOUT: !41 = !DILocalVariable(arg: 1, scope: !36, type: !39)
 // CHECK:STDOUT: !42 = !DILocation(line: 25, column: 23, scope: !36)
-// CHECK:STDOUT: !43 = distinct !DISubprogram(name: "Op", linkageName: "_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.2603c91dd66a1dca", scope: null, file: !44, line: 9, type: !30, spFlags: DISPFlagDefinition, unit: !5)
+// CHECK:STDOUT: !43 = distinct !DISubprogram(name: "Op", linkageName: "_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.4fdc745d4b6d0e3c", scope: null, file: !44, line: 9, type: !30, spFlags: DISPFlagDefinition, unit: !5)
 // CHECK:STDOUT: !44 = !DIFile(filename: "min_prelude/parts/default.carbon", directory: "")
 // CHECK:STDOUT: !45 = !DILocation(line: 9, column: 28, scope: !43)
 // CHECK:STDOUT: !46 = !DILocation(line: 9, column: 21, scope: !43)
@@ -333,7 +333,7 @@ fn GetRefs() {
 // CHECK:STDOUT:   %_.var = alloca i32, align 4, !dbg !17
 // CHECK:STDOUT:   %.loc26_23.2.temp = alloca i32, align 4, !dbg !18
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %c.var), !dbg !14
-// CHECK:STDOUT:   call void @"_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.2603c91dd66a1dca"(ptr %c.var), !dbg !14
+// CHECK:STDOUT:   call void @"_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.4fdc745d4b6d0e3c"(ptr %c.var), !dbg !14
 // CHECK:STDOUT:   call void @_Z8TakeCRefR1C10ForceThunk.carbon_thunk.r(ptr %c.var), !dbg !19
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc20_18.2.temp), !dbg !15
 // CHECK:STDOUT:   call void @_Z9TakeCRRefRK1C10ForceThunk.carbon_thunk._(ptr @C.val.loc20_20.3), !dbg !20
@@ -364,7 +364,7 @@ fn GetRefs() {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: alwaysinline nounwind
-// CHECK:STDOUT: define void @"_COp:thunk:Default.5648bcc2d6c775b7.Core:C.Cpp"(ptr sret({}) %return) #2 !dbg !29 {
+// CHECK:STDOUT: define void @"_COp:thunk:Default.08e786f435a99766.Core:C.Cpp"(ptr sret({}) %return) #2 !dbg !29 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   call void @_ZN1CC1Ev.carbon_thunk.(ptr %return), !dbg !33
 // CHECK:STDOUT:   ret void, !dbg !33
@@ -446,8 +446,8 @@ fn GetRefs() {
 // CHECK:STDOUT: declare void @llvm.lifetime.start.p0(ptr captures(none)) #4
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define linkonce_odr void @"_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.2603c91dd66a1dca"(ptr sret({}) %return) #0 !dbg !45 {
-// CHECK:STDOUT:   call void @"_COp:thunk:Default.5648bcc2d6c775b7.Core:C.Cpp"(ptr %return), !dbg !47
+// CHECK:STDOUT: define linkonce_odr void @"_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.4fdc745d4b6d0e3c"(ptr sret({}) %return) #0 !dbg !45 {
+// CHECK:STDOUT:   call void @"_COp:thunk:Default.08e786f435a99766.Core:C.Cpp"(ptr %return), !dbg !47
 // CHECK:STDOUT:   ret void, !dbg !48
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
@@ -507,7 +507,7 @@ fn GetRefs() {
 // CHECK:STDOUT: !26 = !{!27, !27, i64 0}
 // CHECK:STDOUT: !27 = !{!"p1 _ZTS1C", !28, i64 0}
 // CHECK:STDOUT: !28 = !{!"any pointer", !9, i64 0}
-// CHECK:STDOUT: !29 = distinct !DISubprogram(name: "Op", linkageName: "_COp:thunk:Default.5648bcc2d6c775b7.Core:C.Cpp", scope: null, file: !6, line: 5, type: !30, spFlags: DISPFlagDefinition, unit: !5)
+// CHECK:STDOUT: !29 = distinct !DISubprogram(name: "Op", linkageName: "_COp:thunk:Default.08e786f435a99766.Core:C.Cpp", scope: null, file: !6, line: 5, type: !30, spFlags: DISPFlagDefinition, unit: !5)
 // CHECK:STDOUT: !30 = !DISubroutineType(types: !31)
 // CHECK:STDOUT: !31 = !{!32}
 // CHECK:STDOUT: !32 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: null, size: 64)
@@ -523,7 +523,7 @@ fn GetRefs() {
 // CHECK:STDOUT: !42 = !{!43}
 // CHECK:STDOUT: !43 = !DILocalVariable(arg: 1, scope: !38, type: !41)
 // CHECK:STDOUT: !44 = !DILocation(line: 26, column: 23, scope: !38)
-// CHECK:STDOUT: !45 = distinct !DISubprogram(name: "Op", linkageName: "_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.2603c91dd66a1dca", scope: null, file: !46, line: 9, type: !30, spFlags: DISPFlagDefinition, unit: !5)
+// CHECK:STDOUT: !45 = distinct !DISubprogram(name: "Op", linkageName: "_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.4fdc745d4b6d0e3c", scope: null, file: !46, line: 9, type: !30, spFlags: DISPFlagDefinition, unit: !5)
 // CHECK:STDOUT: !46 = !DIFile(filename: "min_prelude/parts/default.carbon", directory: "")
 // CHECK:STDOUT: !47 = !DILocation(line: 9, column: 28, scope: !45)
 // CHECK:STDOUT: !48 = !DILocation(line: 9, column: 21, scope: !45)

toolchain/lower/testdata/interop/cpp/std_initializer_list.carbon

@@ -232,7 +232,7 @@ fn InitNontrivialDtor() {
 // CHECK:STDOUT:   %initializer_list.initializer_list.call.array.end = getelementptr inbounds [3 x [1 x i8]], ptr %.loc23_69.17.temp, i32 1, !dbg !46
 // CHECK:STDOUT:   store ptr %initializer_list.initializer_list.call.array.end, ptr %initializer_list.initializer_list.call.init_list.end, align 8, !dbg !46
 // CHECK:STDOUT:   call void @_CWithinLifetime.Main(), !dbg !48
-// CHECK:STDOUT:   call void @"_COp.9ec0fd7c1ee9da2c:core.Destroy.Core"(ptr %.loc23_69.17.temp), !dbg !47
+// CHECK:STDOUT:   call void @"_COp.87f8b42e7b26a00a:core.Destroy.Core"(ptr %.loc23_69.17.temp), !dbg !47
 // CHECK:STDOUT:   ret void, !dbg !49
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
@@ -256,7 +256,7 @@ fn InitNontrivialDtor() {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define weak_odr void @"_COp.9ec0fd7c1ee9da2c:core.Destroy.Core"(ptr %self) #0 !dbg !52 {
+// CHECK:STDOUT: define weak_odr void @"_COp.87f8b42e7b26a00a:core.Destroy.Core"(ptr %self) #0 !dbg !52 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   ret void, !dbg !55
 // CHECK:STDOUT: }
@@ -355,7 +355,7 @@ fn InitNontrivialDtor() {
 // CHECK:STDOUT: !49 = !DILocation(line: 22, column: 1, scope: !45)
 // CHECK:STDOUT: !50 = !{!51, !51, i64 0}
 // CHECK:STDOUT: !51 = !{!"p1 _ZTS15nontrivial_dtor", !39, i64 0}
-// CHECK:STDOUT: !52 = distinct !DISubprogram(name: "Op", linkageName: "_COp.9ec0fd7c1ee9da2c:core.Destroy.Core", scope: null, file: !6, line: 23, type: !26, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !53)
+// CHECK:STDOUT: !52 = distinct !DISubprogram(name: "Op", linkageName: "_COp.87f8b42e7b26a00a:core.Destroy.Core", scope: null, file: !6, line: 23, type: !26, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !53)
 // CHECK:STDOUT: !53 = !{!54}
 // CHECK:STDOUT: !54 = !DILocalVariable(arg: 1, scope: !52, type: !28)
 // CHECK:STDOUT: !55 = !DILocation(line: 23, column: 58, scope: !52)
@@ -479,7 +479,7 @@ fn InitNontrivialDtor() {
 // CHECK:STDOUT:   %initializer_list.initializer_list.call.init_list.size = getelementptr inbounds nuw [16 x i8], ptr %_.var, i32 0, i32 8, !dbg !48
 // CHECK:STDOUT:   store i64 3, ptr %initializer_list.initializer_list.call.init_list.size, align 8, !dbg !48
 // CHECK:STDOUT:   call void @_CWithinLifetime.Main(), !dbg !50
-// CHECK:STDOUT:   call void @"_COp.9ec0fd7c1ee9da2c:core.Destroy.Core"(ptr %.loc23_69.17.temp), !dbg !49
+// CHECK:STDOUT:   call void @"_COp.87f8b42e7b26a00a:core.Destroy.Core"(ptr %.loc23_69.17.temp), !dbg !49
 // CHECK:STDOUT:   ret void, !dbg !51
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
@@ -503,7 +503,7 @@ fn InitNontrivialDtor() {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
-// CHECK:STDOUT: define weak_odr void @"_COp.9ec0fd7c1ee9da2c:core.Destroy.Core"(ptr %self) #0 !dbg !54 {
+// CHECK:STDOUT: define weak_odr void @"_COp.87f8b42e7b26a00a:core.Destroy.Core"(ptr %self) #0 !dbg !54 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   ret void, !dbg !57
 // CHECK:STDOUT: }
@@ -604,7 +604,7 @@ fn InitNontrivialDtor() {
 // CHECK:STDOUT: !51 = !DILocation(line: 22, column: 1, scope: !47)
 // CHECK:STDOUT: !52 = !{!53, !53, i64 0}
 // CHECK:STDOUT: !53 = !{!"p1 _ZTS15nontrivial_dtor", !39, i64 0}
-// CHECK:STDOUT: !54 = distinct !DISubprogram(name: "Op", linkageName: "_COp.9ec0fd7c1ee9da2c:core.Destroy.Core", scope: null, file: !6, line: 23, type: !26, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !55)
+// CHECK:STDOUT: !54 = distinct !DISubprogram(name: "Op", linkageName: "_COp.87f8b42e7b26a00a:core.Destroy.Core", scope: null, file: !6, line: 23, type: !26, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !55)
 // CHECK:STDOUT: !55 = !{!56}
 // CHECK:STDOUT: !56 = !DILocalVariable(arg: 1, scope: !54, type: !28)
 // CHECK:STDOUT: !57 = !DILocation(line: 23, column: 58, scope: !54)

toolchain/lower/testdata/interop/cpp/thunks.carbon

@@ -31,6 +31,72 @@ fn Call(n: Cpp.NeedThunk) {
   var unused n2: Cpp.NeedThunk = n;
 }
 
+// --- box.h
+
+struct A {};
+struct B {};
+
+template <typename T>
+struct Box {
+  Box();
+  Box(const Box&);
+  ~Box();
+  T value;
+};
+
+// --- thunks_for_distinct_specializations.carbon
+
+library "[[@TEST_NAME]]";
+
+import Cpp library "box.h";
+
+// Distinct specializations of the same class template share a Carbon name and
+// parent scope, so their `Copy` (and `Destroy`) thunks need distinct mangled
+// names; otherwise they would collide into a single LLVM function. The
+// distinguishing key is the Clang mangled type name recorded when importing a
+// C++ class.
+fn Call(a: Cpp.Box(Cpp.A), b: Cpp.Box(Cpp.B)) {
+  var unused a2: Cpp.Box(Cpp.A) = a;
+  var unused b2: Cpp.Box(Cpp.B) = b;
+}
+
+// --- anonymous_namespace_collision.h
+
+namespace {
+// A type in the anonymous namespace. We expose it under an alias because, once
+// the global `Collide` below is declared, the unqualified name `Collide`
+// refers to that global type.
+struct Collide {
+  Collide() {}
+  Collide(const Collide&) {}
+  ~Collide() {}
+};
+using AnonCollide = Collide;
+}  // namespace
+
+// A *different* type with the same name in the global namespace.
+struct Collide {
+  Collide() {}
+  Collide(const Collide&) {}
+  ~Collide() {}
+};
+
+// --- thunks_for_anonymous_namespace_collision.carbon
+
+library "[[@TEST_NAME]]";
+
+import Cpp library "anonymous_namespace_collision.h";
+
+// `Cpp.Collide` is the global type and `Cpp.AnonCollide` aliases a distinct
+// type of the same name in the anonymous namespace. Carbon sees both as
+// `Collide` with the same parent scope, so their `Copy` thunks would collide
+// into a single LLVM function without the Clang mangled type name (which
+// encodes the anonymous namespace) in the fingerprint.
+fn Call(a: Cpp.Collide, b: Cpp.AnonCollide) {
+  var unused a2: Cpp.Collide = a;
+  var unused b2: Cpp.AnonCollide = b;
+}
+
 // CHECK:STDOUT: ; ModuleID = 'multiple_thunks_in_one_class.carbon'
 // CHECK:STDOUT: source_filename = "multiple_thunks_in_one_class.carbon"
 // CHECK:STDOUT: target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128"
@@ -61,14 +127,14 @@ fn Call(n: Cpp.NeedThunk) {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: alwaysinline nounwind
-// CHECK:STDOUT: define void @"_COp:thunk:Copy.13bba1feb543d868.Core:NeedThunk.Cpp"(ptr sret([1 x i8]) %return, ptr %self) #2 !dbg !23 {
+// CHECK:STDOUT: define void @"_COp:thunk:Copy.4f2f8687b12a420f.Core:NeedThunk.Cpp"(ptr sret([1 x i8]) %return, ptr %self) #2 !dbg !23 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   call void @_ZN9NeedThunkC1ERKS_.carbon_thunk._(ptr %self, ptr %return), !dbg !29
 // CHECK:STDOUT:   ret void, !dbg !29
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: alwaysinline nounwind
-// CHECK:STDOUT: define void @"_COp:thunk:Destroy.57797f2517cd78d7.Core:NeedThunk.Cpp"(ptr %self) #2 !dbg !30 {
+// CHECK:STDOUT: define void @"_COp:thunk:Destroy.54656f03fa721bae.Core:NeedThunk.Cpp"(ptr %self) #2 !dbg !30 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   ret void, !dbg !33
 // CHECK:STDOUT: }
@@ -114,14 +180,305 @@ fn Call(n: Cpp.NeedThunk) {
 // CHECK:STDOUT: !20 = !{!21, !21, i64 0}
 // CHECK:STDOUT: !21 = !{!"p1 _ZTS9NeedThunk", !22, i64 0}
 // CHECK:STDOUT: !22 = !{!"any pointer", !9, i64 0}
-// CHECK:STDOUT: !23 = distinct !DISubprogram(name: "Op", linkageName: "_COp:thunk:Copy.13bba1feb543d868.Core:NeedThunk.Cpp", scope: null, file: !24, line: 4, type: !25, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !27)
+// CHECK:STDOUT: !23 = distinct !DISubprogram(name: "Op", linkageName: "_COp:thunk:Copy.4f2f8687b12a420f.Core:NeedThunk.Cpp", scope: null, file: !24, line: 4, type: !25, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !27)
 // CHECK:STDOUT: !24 = !DIFile(filename: "./need_thunk.h", directory: "")
 // CHECK:STDOUT: !25 = !DISubroutineType(types: !26)
 // CHECK:STDOUT: !26 = !{!14, !14}
 // CHECK:STDOUT: !27 = !{!28}
 // CHECK:STDOUT: !28 = !DILocalVariable(arg: 1, scope: !23, type: !14)
 // CHECK:STDOUT: !29 = !DILocation(line: 4, column: 3, scope: !23)
-// CHECK:STDOUT: !30 = distinct !DISubprogram(name: "Op", linkageName: "_COp:thunk:Destroy.57797f2517cd78d7.Core:NeedThunk.Cpp", scope: null, file: !24, line: 5, type: !12, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !31)
+// CHECK:STDOUT: !30 = distinct !DISubprogram(name: "Op", linkageName: "_COp:thunk:Destroy.54656f03fa721bae.Core:NeedThunk.Cpp", scope: null, file: !24, line: 5, type: !12, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !31)
 // CHECK:STDOUT: !31 = !{!32}
 // CHECK:STDOUT: !32 = !DILocalVariable(arg: 1, scope: !30, type: !14)
 // CHECK:STDOUT: !33 = !DILocation(line: 5, column: 3, scope: !30)
+// CHECK:STDOUT: ; ModuleID = 'thunks_for_distinct_specializations.carbon'
+// CHECK:STDOUT: source_filename = "thunks_for_distinct_specializations.carbon"
+// CHECK:STDOUT: target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128"
+// CHECK:STDOUT: target triple = "x86_64-unknown-linux-gnu"
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: nounwind
+// CHECK:STDOUT: define void @_CCall.Main(ptr %a, ptr %b) #0 !dbg !11 {
+// CHECK:STDOUT: entry:
+// CHECK:STDOUT:   %a2.var = alloca [1 x i8], align 1, !dbg !18
+// CHECK:STDOUT:   %.loc12_35.1.temp = alloca [1 x i8], align 1, !dbg !19
+// CHECK:STDOUT:   %b2.var = alloca [1 x i8], align 1, !dbg !20
+// CHECK:STDOUT:   %.loc13_35.1.temp = alloca [1 x i8], align 1, !dbg !21
+// CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %a2.var), !dbg !18
+// CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc12_35.1.temp), !dbg !19
+// CHECK:STDOUT:   call void @_ZN3BoxI1AEC1ERKS1_.carbon_thunk._(ptr %a, ptr %a2.var), !dbg !19
+// CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %b2.var), !dbg !20
+// CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc13_35.1.temp), !dbg !21
+// CHECK:STDOUT:   call void @_ZN3BoxI1BEC1ERKS1_.carbon_thunk._(ptr %b, ptr %b2.var), !dbg !21
+// CHECK:STDOUT:   call void @_ZN3BoxI1BED1Ev(ptr %b2.var), !dbg !20
+// CHECK:STDOUT:   call void @_ZN3BoxI1AED1Ev(ptr %a2.var), !dbg !18
+// CHECK:STDOUT:   ret void, !dbg !22
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: alwaysinline mustprogress uwtable
+// CHECK:STDOUT: define internal void @_ZN3BoxI1AEC1ERKS1_.carbon_thunk._(ptr noundef %0, ptr noundef %return) #1 {
+// CHECK:STDOUT: entry:
+// CHECK:STDOUT:   %.addr = alloca ptr, align 8
+// CHECK:STDOUT:   %return.addr = alloca ptr, align 8
+// CHECK:STDOUT:   store ptr %0, ptr %.addr, align 8, !tbaa !23
+// CHECK:STDOUT:   store ptr %return, ptr %return.addr, align 8, !tbaa !23
+// CHECK:STDOUT:   %1 = load ptr, ptr %return.addr, align 8, !tbaa !23
+// CHECK:STDOUT:   %2 = load ptr, ptr %.addr, align 8, !tbaa !23
+// CHECK:STDOUT:   call void @_ZN3BoxI1AEC1ERKS1_(ptr noundef nonnull align 1 dereferenceable(1) %1, ptr noundef nonnull align 1 dereferenceable(1) %2)
+// CHECK:STDOUT:   ret void
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: alwaysinline nounwind
+// CHECK:STDOUT: define void @"_COp:thunk:Copy.e1f26893fc85f4d1.Core:Box.Cpp"(ptr sret([1 x i8]) %return, ptr %self) #2 !dbg !26 {
+// CHECK:STDOUT: entry:
+// CHECK:STDOUT:   call void @_ZN3BoxI1AEC1ERKS1_.carbon_thunk._(ptr %self, ptr %return), !dbg !32
+// CHECK:STDOUT:   ret void, !dbg !32
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: alwaysinline mustprogress uwtable
+// CHECK:STDOUT: define internal void @_ZN3BoxI1BEC1ERKS1_.carbon_thunk._(ptr noundef %0, ptr noundef %return) #1 {
+// CHECK:STDOUT: entry:
+// CHECK:STDOUT:   %.addr = alloca ptr, align 8
+// CHECK:STDOUT:   %return.addr = alloca ptr, align 8
+// CHECK:STDOUT:   store ptr %0, ptr %.addr, align 8, !tbaa !33
+// CHECK:STDOUT:   store ptr %return, ptr %return.addr, align 8, !tbaa !33
+// CHECK:STDOUT:   %1 = load ptr, ptr %return.addr, align 8, !tbaa !33
+// CHECK:STDOUT:   %2 = load ptr, ptr %.addr, align 8, !tbaa !33
+// CHECK:STDOUT:   call void @_ZN3BoxI1BEC1ERKS1_(ptr noundef nonnull align 1 dereferenceable(1) %1, ptr noundef nonnull align 1 dereferenceable(1) %2)
+// CHECK:STDOUT:   ret void
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: alwaysinline nounwind
+// CHECK:STDOUT: define void @"_COp:thunk:Copy.0fba185d40847304.Core:Box.Cpp"(ptr sret([1 x i8]) %return, ptr %self) #2 !dbg !35 {
+// CHECK:STDOUT: entry:
+// CHECK:STDOUT:   call void @_ZN3BoxI1BEC1ERKS1_.carbon_thunk._(ptr %self, ptr %return), !dbg !38
+// CHECK:STDOUT:   ret void, !dbg !38
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: nounwind
+// CHECK:STDOUT: declare void @_ZN3BoxI1BED1Ev(ptr noundef nonnull align 1 dead_on_return(1) dereferenceable(1)) unnamed_addr #3
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: nounwind
+// CHECK:STDOUT: declare void @_ZN3BoxI1AED1Ev(ptr noundef nonnull align 1 dead_on_return(1) dereferenceable(1)) unnamed_addr #3
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
+// CHECK:STDOUT: declare void @llvm.lifetime.start.p0(ptr captures(none)) #4
+// CHECK:STDOUT:
+// CHECK:STDOUT: declare void @_ZN3BoxI1AEC1ERKS1_(ptr noundef nonnull align 1 dereferenceable(1), ptr noundef nonnull align 1 dereferenceable(1)) unnamed_addr #5
+// CHECK:STDOUT:
+// CHECK:STDOUT: declare void @_ZN3BoxI1BEC1ERKS1_(ptr noundef nonnull align 1 dereferenceable(1), ptr noundef nonnull align 1 dereferenceable(1)) unnamed_addr #5
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; uselistorder directives
+// CHECK:STDOUT: uselistorder ptr @llvm.lifetime.start.p0, { 3, 2, 1, 0 }
+// CHECK:STDOUT:
+// CHECK:STDOUT: attributes #0 = { nounwind }
+// CHECK:STDOUT: attributes #1 = { alwaysinline mustprogress uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
+// CHECK:STDOUT: attributes #2 = { alwaysinline nounwind }
+// CHECK:STDOUT: attributes #3 = { nounwind "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
+// CHECK:STDOUT: attributes #4 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
+// CHECK:STDOUT: attributes #5 = { "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
+// CHECK:STDOUT:
+// CHECK:STDOUT: !llvm.module.flags = !{!0, !1, !2, !3, !4}
+// CHECK:STDOUT: !llvm.dbg.cu = !{!5}
+// CHECK:STDOUT: !llvm.errno.tbaa = !{!7}
+// CHECK:STDOUT:
+// CHECK:STDOUT: !0 = !{i32 7, !"Dwarf Version", i32 5}
+// CHECK:STDOUT: !1 = !{i32 2, !"Debug Info Version", i32 3}
+// CHECK:STDOUT: !2 = !{i32 8, !"PIC Level", i32 2}
+// CHECK:STDOUT: !3 = !{i32 7, !"PIE Level", i32 2}
+// CHECK:STDOUT: !4 = !{i32 7, !"uwtable", i32 2}
+// CHECK:STDOUT: !5 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !6, producer: "carbon", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug)
+// CHECK:STDOUT: !6 = !DIFile(filename: "thunks_for_distinct_specializations.carbon", directory: "")
+// CHECK:STDOUT: !7 = !{!8, !8, i64 0}
+// CHECK:STDOUT: !8 = !{!"int", !9, i64 0}
+// CHECK:STDOUT: !9 = !{!"omnipotent char", !10, i64 0}
+// CHECK:STDOUT: !10 = !{!"Simple C++ TBAA"}
+// CHECK:STDOUT: !11 = distinct !DISubprogram(name: "Call", linkageName: "_CCall.Main", scope: null, file: !6, line: 11, type: !12, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !15)
+// CHECK:STDOUT: !12 = !DISubroutineType(types: !13)
+// CHECK:STDOUT: !13 = !{null, !14, !14}
+// CHECK:STDOUT: !14 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: null, size: 64)
+// CHECK:STDOUT: !15 = !{!16, !17}
+// CHECK:STDOUT: !16 = !DILocalVariable(arg: 1, scope: !11, type: !14)
+// CHECK:STDOUT: !17 = !DILocalVariable(arg: 2, scope: !11, type: !14)
+// CHECK:STDOUT: !18 = !DILocation(line: 12, column: 3, scope: !11)
+// CHECK:STDOUT: !19 = !DILocation(line: 12, column: 35, scope: !11)
+// CHECK:STDOUT: !20 = !DILocation(line: 13, column: 3, scope: !11)
+// CHECK:STDOUT: !21 = !DILocation(line: 13, column: 35, scope: !11)
+// CHECK:STDOUT: !22 = !DILocation(line: 11, column: 1, scope: !11)
+// CHECK:STDOUT: !23 = !{!24, !24, i64 0}
+// CHECK:STDOUT: !24 = !{!"p1 _ZTS3BoxI1AE", !25, i64 0}
+// CHECK:STDOUT: !25 = !{!"any pointer", !9, i64 0}
+// CHECK:STDOUT: !26 = distinct !DISubprogram(name: "Op", linkageName: "_COp:thunk:Copy.e1f26893fc85f4d1.Core:Box.Cpp", scope: null, file: !27, line: 8, type: !28, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !30)
+// CHECK:STDOUT: !27 = !DIFile(filename: "./box.h", directory: "")
+// CHECK:STDOUT: !28 = !DISubroutineType(types: !29)
+// CHECK:STDOUT: !29 = !{!14, !14}
+// CHECK:STDOUT: !30 = !{!31}
+// CHECK:STDOUT: !31 = !DILocalVariable(arg: 1, scope: !26, type: !14)
+// CHECK:STDOUT: !32 = !DILocation(line: 8, column: 3, scope: !26)
+// CHECK:STDOUT: !33 = !{!34, !34, i64 0}
+// CHECK:STDOUT: !34 = !{!"p1 _ZTS3BoxI1BE", !25, i64 0}
+// CHECK:STDOUT: !35 = distinct !DISubprogram(name: "Op", linkageName: "_COp:thunk:Copy.0fba185d40847304.Core:Box.Cpp", scope: null, file: !27, line: 8, type: !28, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !36)
+// CHECK:STDOUT: !36 = !{!37}
+// CHECK:STDOUT: !37 = !DILocalVariable(arg: 1, scope: !35, type: !14)
+// CHECK:STDOUT: !38 = !DILocation(line: 8, column: 3, scope: !35)
+// CHECK:STDOUT: ; ModuleID = 'thunks_for_anonymous_namespace_collision.carbon'
+// CHECK:STDOUT: source_filename = "thunks_for_anonymous_namespace_collision.carbon"
+// CHECK:STDOUT: target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128"
+// CHECK:STDOUT: target triple = "x86_64-unknown-linux-gnu"
+// CHECK:STDOUT:
+// CHECK:STDOUT: $_ZN7CollideD2Ev = comdat any
+// CHECK:STDOUT:
+// CHECK:STDOUT: $_ZN7CollideC2ERKS_ = comdat any
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: nounwind
+// CHECK:STDOUT: define void @_CCall.Main(ptr %a, ptr %b) #0 !dbg !11 {
+// CHECK:STDOUT: entry:
+// CHECK:STDOUT:   %a2.var = alloca [1 x i8], align 1, !dbg !18
+// CHECK:STDOUT:   %.loc12_32.1.temp = alloca [1 x i8], align 1, !dbg !19
+// CHECK:STDOUT:   %b2.var = alloca [1 x i8], align 1, !dbg !20
+// CHECK:STDOUT:   %.loc13_36.1.temp = alloca [1 x i8], align 1, !dbg !21
+// CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %a2.var), !dbg !18
+// CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc12_32.1.temp), !dbg !19
+// CHECK:STDOUT:   call void @_ZN7CollideC1ERKS_.carbon_thunk._(ptr %a, ptr %a2.var), !dbg !19
+// CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %b2.var), !dbg !20
+// CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc13_36.1.temp), !dbg !21
+// CHECK:STDOUT:   call void @_ZN12_GLOBAL__N_17CollideC1ERKS0_.carbon_thunk._(ptr %b, ptr %b2.var), !dbg !21
+// CHECK:STDOUT:   call void @_ZN12_GLOBAL__N_17CollideD2Ev(ptr %b2.var), !dbg !20
+// CHECK:STDOUT:   call void @_ZN7CollideD2Ev(ptr %a2.var), !dbg !18
+// CHECK:STDOUT:   ret void, !dbg !22
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: alwaysinline mustprogress uwtable
+// CHECK:STDOUT: define internal void @_ZN7CollideC1ERKS_.carbon_thunk._(ptr noundef %0, ptr noundef %return) #1 {
+// CHECK:STDOUT: entry:
+// CHECK:STDOUT:   %.addr = alloca ptr, align 8
+// CHECK:STDOUT:   %return.addr = alloca ptr, align 8
+// CHECK:STDOUT:   store ptr %0, ptr %.addr, align 8, !tbaa !23
+// CHECK:STDOUT:   store ptr %return, ptr %return.addr, align 8, !tbaa !23
+// CHECK:STDOUT:   %1 = load ptr, ptr %return.addr, align 8, !tbaa !23
+// CHECK:STDOUT:   %2 = load ptr, ptr %.addr, align 8, !tbaa !23
+// CHECK:STDOUT:   call void @_ZN7CollideC2ERKS_(ptr noundef nonnull align 1 dereferenceable(1) %1, ptr noundef nonnull align 1 dereferenceable(1) %2)
+// CHECK:STDOUT:   ret void
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: alwaysinline nounwind
+// CHECK:STDOUT: define void @"_COp:thunk:Copy.289c71441a159c5c.Core:Collide.Cpp"(ptr sret([1 x i8]) %return, ptr %self) #2 !dbg !26 {
+// CHECK:STDOUT: entry:
+// CHECK:STDOUT:   call void @_ZN7CollideC1ERKS_.carbon_thunk._(ptr %self, ptr %return), !dbg !32
+// CHECK:STDOUT:   ret void, !dbg !32
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: alwaysinline mustprogress uwtable
+// CHECK:STDOUT: define internal void @_ZN12_GLOBAL__N_17CollideC1ERKS0_.carbon_thunk._(ptr noundef %0, ptr noundef %return) #1 {
+// CHECK:STDOUT: entry:
+// CHECK:STDOUT:   %.addr = alloca ptr, align 8
+// CHECK:STDOUT:   %return.addr = alloca ptr, align 8
+// CHECK:STDOUT:   store ptr %0, ptr %.addr, align 8, !tbaa !33
+// CHECK:STDOUT:   store ptr %return, ptr %return.addr, align 8, !tbaa !33
+// CHECK:STDOUT:   %1 = load ptr, ptr %return.addr, align 8, !tbaa !33
+// CHECK:STDOUT:   %2 = load ptr, ptr %.addr, align 8, !tbaa !33
+// CHECK:STDOUT:   call void @_ZN12_GLOBAL__N_17CollideC2ERKS0_(ptr noundef nonnull align 1 dereferenceable(1) %1, ptr noundef nonnull align 1 dereferenceable(1) %2)
+// CHECK:STDOUT:   ret void
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: alwaysinline nounwind
+// CHECK:STDOUT: define void @"_COp:thunk:Copy.4bff6a47276e2ca8.Core:Collide..Cpp"(ptr sret([1 x i8]) %return, ptr %self) #2 !dbg !35 {
+// CHECK:STDOUT: entry:
+// CHECK:STDOUT:   call void @_ZN12_GLOBAL__N_17CollideC1ERKS0_.carbon_thunk._(ptr %self, ptr %return), !dbg !38
+// CHECK:STDOUT:   ret void, !dbg !38
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: mustprogress nounwind uwtable
+// CHECK:STDOUT: define internal void @_ZN12_GLOBAL__N_17CollideD2Ev(ptr noundef nonnull align 1 dereferenceable(1) %this) unnamed_addr #3 align 2 {
+// CHECK:STDOUT: entry:
+// CHECK:STDOUT:   %this.addr = alloca ptr, align 8
+// CHECK:STDOUT:   store ptr %this, ptr %this.addr, align 8, !tbaa !33
+// CHECK:STDOUT:   %this1 = load ptr, ptr %this.addr, align 8
+// CHECK:STDOUT:   ret void
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: mustprogress nounwind uwtable
+// CHECK:STDOUT: define linkonce_odr dso_local void @_ZN7CollideD2Ev(ptr noundef nonnull align 1 dereferenceable(1) %this) unnamed_addr #3 comdat align 2 {
+// CHECK:STDOUT: entry:
+// CHECK:STDOUT:   %this.addr = alloca ptr, align 8
+// CHECK:STDOUT:   store ptr %this, ptr %this.addr, align 8, !tbaa !23
+// CHECK:STDOUT:   %this1 = load ptr, ptr %this.addr, align 8
+// CHECK:STDOUT:   ret void
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
+// CHECK:STDOUT: declare void @llvm.lifetime.start.p0(ptr captures(none)) #4
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: mustprogress nounwind uwtable
+// CHECK:STDOUT: define linkonce_odr dso_local void @_ZN7CollideC2ERKS_(ptr noundef nonnull align 1 dereferenceable(1) %this, ptr noundef nonnull align 1 dereferenceable(1) %0) unnamed_addr #3 comdat align 2 {
+// CHECK:STDOUT: entry:
+// CHECK:STDOUT:   %this.addr = alloca ptr, align 8
+// CHECK:STDOUT:   %.addr = alloca ptr, align 8
+// CHECK:STDOUT:   store ptr %this, ptr %this.addr, align 8, !tbaa !23
+// CHECK:STDOUT:   store ptr %0, ptr %.addr, align 8, !tbaa !23
+// CHECK:STDOUT:   %this1 = load ptr, ptr %this.addr, align 8
+// CHECK:STDOUT:   ret void
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: mustprogress nounwind uwtable
+// CHECK:STDOUT: define internal void @_ZN12_GLOBAL__N_17CollideC2ERKS0_(ptr noundef nonnull align 1 dereferenceable(1) %this, ptr noundef nonnull align 1 dereferenceable(1) %0) unnamed_addr #3 align 2 {
+// CHECK:STDOUT: entry:
+// CHECK:STDOUT:   %this.addr = alloca ptr, align 8
+// CHECK:STDOUT:   %.addr = alloca ptr, align 8
+// CHECK:STDOUT:   store ptr %this, ptr %this.addr, align 8, !tbaa !33
+// CHECK:STDOUT:   store ptr %0, ptr %.addr, align 8, !tbaa !33
+// CHECK:STDOUT:   %this1 = load ptr, ptr %this.addr, align 8
+// CHECK:STDOUT:   ret void
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; uselistorder directives
+// CHECK:STDOUT: uselistorder ptr @llvm.lifetime.start.p0, { 3, 2, 1, 0 }
+// CHECK:STDOUT:
+// CHECK:STDOUT: attributes #0 = { nounwind }
+// CHECK:STDOUT: attributes #1 = { alwaysinline mustprogress uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
+// CHECK:STDOUT: attributes #2 = { alwaysinline nounwind }
+// CHECK:STDOUT: attributes #3 = { mustprogress nounwind uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
+// CHECK:STDOUT: attributes #4 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
+// CHECK:STDOUT:
+// CHECK:STDOUT: !llvm.module.flags = !{!0, !1, !2, !3, !4}
+// CHECK:STDOUT: !llvm.dbg.cu = !{!5}
+// CHECK:STDOUT: !llvm.errno.tbaa = !{!7}
+// CHECK:STDOUT:
+// CHECK:STDOUT: !0 = !{i32 7, !"Dwarf Version", i32 5}
+// CHECK:STDOUT: !1 = !{i32 2, !"Debug Info Version", i32 3}
+// CHECK:STDOUT: !2 = !{i32 8, !"PIC Level", i32 2}
+// CHECK:STDOUT: !3 = !{i32 7, !"PIE Level", i32 2}
+// CHECK:STDOUT: !4 = !{i32 7, !"uwtable", i32 2}
+// CHECK:STDOUT: !5 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !6, producer: "carbon", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug)
+// CHECK:STDOUT: !6 = !DIFile(filename: "thunks_for_anonymous_namespace_collision.carbon", directory: "")
+// CHECK:STDOUT: !7 = !{!8, !8, i64 0}
+// CHECK:STDOUT: !8 = !{!"int", !9, i64 0}
+// CHECK:STDOUT: !9 = !{!"omnipotent char", !10, i64 0}
+// CHECK:STDOUT: !10 = !{!"Simple C++ TBAA"}
+// CHECK:STDOUT: !11 = distinct !DISubprogram(name: "Call", linkageName: "_CCall.Main", scope: null, file: !6, line: 11, type: !12, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !15)
+// CHECK:STDOUT: !12 = !DISubroutineType(types: !13)
+// CHECK:STDOUT: !13 = !{null, !14, !14}
+// CHECK:STDOUT: !14 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: null, size: 64)
+// CHECK:STDOUT: !15 = !{!16, !17}
+// CHECK:STDOUT: !16 = !DILocalVariable(arg: 1, scope: !11, type: !14)
+// CHECK:STDOUT: !17 = !DILocalVariable(arg: 2, scope: !11, type: !14)
+// CHECK:STDOUT: !18 = !DILocation(line: 12, column: 3, scope: !11)
+// CHECK:STDOUT: !19 = !DILocation(line: 12, column: 32, scope: !11)
+// CHECK:STDOUT: !20 = !DILocation(line: 13, column: 3, scope: !11)
+// CHECK:STDOUT: !21 = !DILocation(line: 13, column: 36, scope: !11)
+// CHECK:STDOUT: !22 = !DILocation(line: 11, column: 1, scope: !11)
+// CHECK:STDOUT: !23 = !{!24, !24, i64 0}
+// CHECK:STDOUT: !24 = !{!"p1 _ZTS7Collide", !25, i64 0}
+// CHECK:STDOUT: !25 = !{!"any pointer", !9, i64 0}
+// CHECK:STDOUT: !26 = distinct !DISubprogram(name: "Op", linkageName: "_COp:thunk:Copy.289c71441a159c5c.Core:Collide.Cpp", scope: null, file: !27, line: 17, type: !28, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !30)
+// CHECK:STDOUT: !27 = !DIFile(filename: "./anonymous_namespace_collision.h", directory: "")
+// CHECK:STDOUT: !28 = !DISubroutineType(types: !29)
+// CHECK:STDOUT: !29 = !{!14, !14}
+// CHECK:STDOUT: !30 = !{!31}
+// CHECK:STDOUT: !31 = !DILocalVariable(arg: 1, scope: !26, type: !14)
+// CHECK:STDOUT: !32 = !DILocation(line: 17, column: 3, scope: !26)
+// CHECK:STDOUT: !33 = !{!34, !34, i64 0}
+// CHECK:STDOUT: !34 = !{!"p1 _ZTSN12_GLOBAL__N_17CollideE", !25, i64 0}
+// CHECK:STDOUT: !35 = distinct !DISubprogram(name: "Op", linkageName: "_COp:thunk:Copy.4bff6a47276e2ca8.Core:Collide..Cpp", scope: null, file: !27, line: 8, type: !28, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !36)
+// CHECK:STDOUT: !36 = !{!37}
+// CHECK:STDOUT: !37 = !DILocalVariable(arg: 1, scope: !35, type: !14)
+// CHECK:STDOUT: !38 = !DILocation(line: 8, column: 3, scope: !35)