Merge pull request #38304 from slavapestov/fix-assoc-type-path-mangling

IRGen: Consistently mangle 'associated type paths' without a generic signature

Author: slavapestov

lib/IRGen/IRGenMangler.cpp

@@ -288,6 +288,10 @@ std::string IRGenMangler::mangleSymbolNameForAssociatedConformanceWitness(
     Buffer << "default associated conformance";
   }
 
+  // appendProtocolConformance() sets CurGenericSignature; clear it out
+  // before calling appendAssociatedTypePath().
+  CurGenericSignature = nullptr;
+
   bool isFirstAssociatedTypeIdentifier = true;
   appendAssociatedTypePath(associatedType, isFirstAssociatedTypeIdentifier);
   appendProtocolName(proto);

lib/IRGen/IRGenMangler.h

@@ -426,6 +426,11 @@ class IRGenMangler : public Mangle::ASTMangler {
                                       const ProtocolDecl *Proto) {
     beginMangling();
     appendProtocolConformance(Conformance);
+
+    // appendProtocolConformance() sets CurGenericSignature; clear it out
+    // before calling appendAssociatedTypePath().
+    CurGenericSignature = nullptr;
+
     bool isFirstAssociatedTypeIdentifier = true;
     appendAssociatedTypePath(AssociatedType, isFirstAssociatedTypeIdentifier);
     appendAnyGenericType(Proto);
@@ -444,6 +449,10 @@ class IRGenMangler : public Mangle::ASTMangler {
   }
 
   void appendAssociatedTypePath(CanType associatedType, bool &isFirst) {
+    // In the mangling format, the "short associated type" optimization is
+    // not performed when mangling an associated type path.
+    assert(!CurGenericSignature && "Caller needs to explicitly clear the signature");
+
     if (auto memberType = dyn_cast<DependentMemberType>(associatedType)) {
       appendAssociatedTypePath(memberType.getBase(), isFirst);
       appendAssociatedTypeName(memberType);

test/IRGen/associated_type_witness.swift

@@ -50,8 +50,8 @@ struct WithUniversal : Assocked {
 //   Witness table for GenericWithUniversal : Assocked.
 // GLOBAL-LABEL: @"$s23associated_type_witness20GenericWithUniversalVyxGAA8AssockedAAWP" = hidden global [4 x i8*] [
 // GLOBAL-SAME:    @"$s23associated_type_witness20GenericWithUniversalVyxGAA8AssockedAAMc"
-// GLOBAL-SAME:    @"associated conformance 23associated_type_witness20GenericWithUniversalVyxGAA8AssockedAA5Assoc_AA1P"
-// GLOBAL-SAME:    @"associated conformance 23associated_type_witness20GenericWithUniversalVyxGAA8AssockedAA5Assoc_AA1Q"
+// GLOBAL-SAME:    @"associated conformance 23associated_type_witness20GenericWithUniversalVyxGAA8AssockedAA5AssocAaEP_AA1P"
+// GLOBAL-SAME:    @"associated conformance 23associated_type_witness20GenericWithUniversalVyxGAA8AssockedAA5AssocAaEP_AA1Q"
 // GLOBAL-SAME:    @"symbolic{{.*}}23associated_type_witness9UniversalV"
 // GLOBAL-SAME:  ]
 struct GenericWithUniversal<T> : Assocked {
@@ -88,8 +88,8 @@ struct Pair<T, U> : P, Q {}
 //   Generic witness table pattern for Computed : Assocked.
 // GLOBAL-LABEL: @"$s23associated_type_witness8ComputedVyxq_GAA8AssockedAAWp" = internal global [4 x i8*] [
 // GLOBAL-SAME:    @"$s23associated_type_witness8ComputedVyxq_GAA8AssockedAAMc"
-// GLOBAL-SAME:    @"associated conformance 23associated_type_witness8ComputedVyxq_GAA8AssockedAA5Assoc_AA1P"
-// GLOBAL-SAME:    @"associated conformance 23associated_type_witness8ComputedVyxq_GAA8AssockedAA5Assoc_AA1Q"
+// GLOBAL-SAME:    @"associated conformance 23associated_type_witness8ComputedVyxq_GAA8AssockedAA5AssocAaEP_AA1P"
+// GLOBAL-SAME:    @"associated conformance 23associated_type_witness8ComputedVyxq_GAA8AssockedAA5AssocAaEP_AA1Q"
 // GLOBAL-SAME:    @"symbolic{{.*}}23associated_type_witness4PairV{{.*}}"
 // GLOBAL-SAME:  ]
 

test/IRGen/assoctypepath.swift

@@ -17,7 +17,7 @@ protocol P {
 protocol Q: P where A: Z {}
 protocol R: Q where A.ZZ: Y {}
 
-// CHECK: define {{.*}} @"$s13assoctypepath1SVyxGAA1RAA1A_2ZZAA1YPWT"
+// CHECK: define {{.*}} @"$s13assoctypepath1SVyxGAA1RAA1AAA1PP_2ZZAA1ZPAA1YPWT"
 
 struct S<T>: R where T: Z, T.ZZ: Y {
 	typealias A = T

test/IRGen/opaque_result_type_associated_type_conformance_path.swift

@@ -14,7 +14,7 @@ struct Foo<T: Tubb>: P {
   func foo(_ x: T) -> some Tubb { return x }
 }
 
-// CHECK-LABEL: define {{.*}} @"$s030opaque_result_type_associated_C17_conformance_path3FooVyxGAA1PAA1B_AA4ButtPWT"
+// CHECK-LABEL: define {{.*}} @"$s030opaque_result_type_associated_C17_conformance_path3FooVyxGAA1PAA1AAaEP_AA4ButtPWT"
 // CHECK: [[TUBB_CONFORMANCE:%.*]] = call swiftcc i8** @swift_getOpaqueTypeConformance({{.*}}, i{{.*}} 1)
 // CHECK: [[BUTT_CONFORMANCE_ADDR:%.*]] = getelementptr {{.*}} [[TUBB_CONFORMANCE]], i32 1
 // CHECK: [[BUTT_CONFORMANCE_LOAD:%.*]] = load {{.*}} [[BUTT_CONFORMANCE_ADDR]]

test/IRGen/same_type_constraints.swift

@@ -67,7 +67,7 @@ where Self : CodingType,
   print(Self.ValueType.self)
 }
 
-// OSIZE: define internal swiftcc i8** @"$s21same_type_constraints12GenericKlazzCyxq_GAA1EAA4Data_AA0F4TypePWT"(%swift.type* readnone %"GenericKlazz<T, R>.Data", %swift.type* nocapture readonly %"GenericKlazz<T, R>", i8** nocapture readnone %"GenericKlazz<T, R>.E") [[ATTRS:#[0-9]+]] {
+// OSIZE: define internal swiftcc i8** @"$s21same_type_constraints12GenericKlazzCyxq_GAA1EAA4DataAaEP_AA0F4TypePWT"(%swift.type* readnone %"GenericKlazz<T, R>.Data", %swift.type* nocapture readonly %"GenericKlazz<T, R>", i8** nocapture readnone %"GenericKlazz<T, R>.E") [[ATTRS:#[0-9]+]] {
 // OSIZE: [[ATTRS]] = {{{.*}}noinline
 
 // Check that same-typing two generic parameters together lowers correctly.

test/Inputs/conditional_conformance_recursive.swift

@@ -19,7 +19,7 @@ protocol P3: P2 where A: P3 { }
 extension Wrapper: P3 where T: P3 { }
 
 // associated type witness table accessor for A : P2 in Wrapper<T>: P2
-// CHECK-LABEL: define internal swiftcc i8** @"$s33conditional_conformance_recursive7WrapperVyxGAA2P2A2aERzrl1A_AaEPWT"
+// CHECK-LABEL: define internal swiftcc i8** @"$s33conditional_conformance_recursive7WrapperVyxGAA2P2A2aERzrl1AAA2P1P_AaEPWT"
 // CHECK: [[CONDITIONAL_REQ_BUFFER:%.*]] = alloca [1 x i8**]
 // CHECK: [[FIRST_REQ:%.*]] = getelementptr inbounds [1 x i8**], [1 x i8**]* [[CONDITIONAL_REQ_BUFFER]]
 // CHECK: call i8** @swift_getWitnessTable