swiftlang · nate-chandler · Jun 24, 2020 · Jun 20, 2020
diff --git a/lib/IRGen/MetadataRequest.cpp b/lib/IRGen/MetadataRequest.cpp
@@ -1953,16 +1953,51 @@ static void emitCanonicalSpecializationsForGenericTypeMetadataAccessFunction(
       auto requirements = GenericTypeRequirements(IGF.IGM, nominal);
       int requirementIndex = 0;
       for (auto requirement : requirements.getRequirements()) {
-        if (requirement.Protocol) {
-          continue;
-        }
         auto parameter = requirement.TypeParameter;
         auto argument = parameter.subst(substitutions);
-        llvm::Constant *addr =
-            IGM.getAddrOfTypeMetadata(argument->getCanonicalType());
-        auto addrInt = IGF.Builder.CreateBitCast(addr, IGM.Int8PtrTy);
-        condition = IGF.Builder.CreateAnd(
-            condition, IGF.Builder.CreateICmpEQ(addrInt, valueAtIndex(requirementIndex)));
+        if (requirement.Protocol) {
+          auto conformance = substitutions.lookupConformance(
+              requirement.TypeParameter->getCanonicalType(),
+              requirement.Protocol);
+          ProtocolConformance *concreteConformance = conformance.getConcrete();
+          auto argumentNominal = argument->getAnyNominal();
+          if (argumentNominal && argumentNominal->isGenericContext()) {
+            // TODO: Statically specialize the witness table pattern for t's
+            //       conformance.
+            llvm_unreachable(
+                "Statically specializing metadata at generic types is "
+                "not supported.");
+          } else {
+            RootProtocolConformance *rootConformance =
+                concreteConformance->getRootConformance();
+            auto *expectedDescriptor =
+                IGF.IGM.getAddrOfProtocolConformanceDescriptor(rootConformance);
+            auto *witnessTable = valueAtIndex(requirementIndex);
+            auto *witnessBuffer =
+                IGF.Builder.CreateBitCast(witnessTable, IGM.Int8PtrPtrTy);
+            auto *uncastProvidedDescriptor =
+                IGF.Builder.CreateLoad(witnessBuffer, Alignment());
+            auto *providedDescriptor = IGF.Builder.CreateBitCast(
+                uncastProvidedDescriptor,
+                IGM.ProtocolConformanceDescriptorPtrTy);
+
+            auto *call = IGF.Builder.CreateCall(
+                IGF.IGM.getCompareProtocolConformanceDescriptorsFn(),
+                {providedDescriptor, expectedDescriptor});
+            call->setDoesNotThrow();
+            call->setCallingConv(IGF.IGM.SwiftCC);
+            call->addAttribute(llvm::AttributeList::FunctionIndex,
+                               llvm::Attribute::ReadNone);
+            condition = IGF.Builder.CreateAnd(condition, call);
+          }
+        } else {
+          llvm::Constant *addr =
+              IGM.getAddrOfTypeMetadata(argument->getCanonicalType());
+          auto addrInt = IGF.Builder.CreateBitCast(addr, IGM.Int8PtrTy);
+          condition = IGF.Builder.CreateAnd(
+              condition, IGF.Builder.CreateICmpEQ(
+                             addrInt, valueAtIndex(requirementIndex)));
+        }
         ++requirementIndex;
       }
       IGF.Builder.CreateCondBr(condition, specializationBlock, successorBlock);
@@ -2053,7 +2088,6 @@ MetadataResponse irgen::emitGenericTypeMetadataAccessFunction(
     emitCanonicalSpecializationsForGenericTypeMetadataAccessFunction(
         IGF, request, nominal, genericArgs, [&](int index) {
           llvm::Value *indexValue = llvm::ConstantInt::get(IGM.Int64Ty, index);
-          llvm::SmallVector<llvm::Value *, 1> indices{indexValue};
           llvm::Value *elementPointer =
               IGF.Builder.CreateGEP(argumentsBuffer, indexValue);
           llvm::LoadInst *retval = IGF.Builder.CreateLoad(

diff --git a/test/IRGen/prespecialized-metadata/enum-inmodule-1argument-1conformance-1distinct_use.swift b/test/IRGen/prespecialized-metadata/enum-inmodule-1argument-1conformance-1distinct_use.swift
@@ -72,7 +72,12 @@ doit()
 // CHECK: [[TYPE_COMPARISON_LABEL]]:
 // CHECK:   [[EQUAL_TYPE:%[0-9]+]] = icmp eq i8* bitcast (%swift.type* @"$sSiN" to i8*), [[ERASED_TYPE]]
 // CHECK:   [[EQUAL_TYPES:%[0-9]+]] = and i1 true, [[EQUAL_TYPE]]
-// CHECK:   br i1 [[EQUAL_TYPES]], label %[[EXIT_PRESPECIALIZED:[0-9]+]], label %[[EXIT_NORMAL:[0-9]+]]
+// CHECK:   [[ARGUMENT_BUFFER:%[0-9]+]] = bitcast i8* [[ERASED_TABLE]] to i8**
+// CHECK:   [[UNCAST_PROVIDED_PROTOCOL_DESCRIPTOR:%[0-9]+]] = load i8*, i8** [[ARGUMENT_BUFFER]], align 1
+// CHECK:   [[PROVIDED_PROTOCOL_DESCRIPTOR:%[0-9]+]] = bitcast i8* [[UNCAST_PROVIDED_PROTOCOL_DESCRIPTOR]] to %swift.protocol_conformance_descriptor*
+// CHECK:   [[EQUAL_DESCRIPTORS:%[0-9]+]] = call swiftcc i1 @swift_compareProtocolConformanceDescriptors(%swift.protocol_conformance_descriptor* [[PROVIDED_PROTOCOL_DESCRIPTOR]], %swift.protocol_conformance_descriptor* @"$sSi4main1PAAMc")
+// CHECK:   [[EQUAL_ARGUMENTS:%[0-9]+]] = and i1 [[EQUAL_TYPES]], [[EQUAL_DESCRIPTORS]]
+// CHECK:   br i1 [[EQUAL_ARGUMENTS]], label %[[EXIT_PRESPECIALIZED:[0-9]+]], label %[[EXIT_NORMAL:[0-9]+]]
 // CHECK: [[EXIT_PRESPECIALIZED]]:
 // CHECK:   ret %swift.metadata_response { 
 // CHECK-SAME:     %swift.type* getelementptr inbounds (

diff --git a/...n/prespecialized-metadata/enum-inmodule-1argument-1conformance-public-1distinct_use.swift b/...n/prespecialized-metadata/enum-inmodule-1argument-1conformance-public-1distinct_use.swift
@@ -72,7 +72,12 @@ doit()
 // CHECK: [[TYPE_COMPARISON_LABEL]]:
 // CHECK:   [[EQUAL_TYPE:%[0-9]+]] = icmp eq i8* bitcast (%swift.type* @"$sSiN" to i8*), [[ERASED_TYPE]]
 // CHECK:   [[EQUAL_TYPES:%[0-9]+]] = and i1 true, [[EQUAL_TYPE]]
-// CHECK:   br i1 [[EQUAL_TYPES]], label %[[EXIT_PRESPECIALIZED:[0-9]+]], label %[[EXIT_NORMAL:[0-9]+]]
+// CHECK:   [[ARGUMENT_BUFFER:%[0-9]+]] = bitcast i8* [[ERASED_TABLE]] to i8**
+// CHECK:   [[UNCAST_PROVIDED_PROTOCOL_DESCRIPTOR:%[0-9]+]] = load i8*, i8** [[ARGUMENT_BUFFER]], align 1
+// CHECK:   [[PROVIDED_PROTOCOL_DESCRIPTOR:%[0-9]+]] = bitcast i8* [[UNCAST_PROVIDED_PROTOCOL_DESCRIPTOR]] to %swift.protocol_conformance_descriptor*
+// CHECK:   [[EQUAL_DESCRIPTORS:%[0-9]+]] = call swiftcc i1 @swift_compareProtocolConformanceDescriptors(%swift.protocol_conformance_descriptor* [[PROVIDED_PROTOCOL_DESCRIPTOR]], %swift.protocol_conformance_descriptor* @"$sSi4main1PAAMc")
+// CHECK:   [[EQUAL_ARGUMENTS:%[0-9]+]] = and i1 [[EQUAL_TYPES]], [[EQUAL_DESCRIPTORS]]
+// CHECK:   br i1 [[EQUAL_ARGUMENTS]], label %[[EXIT_PRESPECIALIZED:[0-9]+]], label %[[EXIT_NORMAL:[0-9]+]]
 // CHECK: [[EXIT_PRESPECIALIZED]]:
 // CHECK:   ret %swift.metadata_response { 
 // CHECK-SAME:     %swift.type* getelementptr inbounds (

diff --git a/.../IRGen/prespecialized-metadata/struct-inmodule-1argument-1conformance-1distinct_use.swift b/.../IRGen/prespecialized-metadata/struct-inmodule-1argument-1conformance-1distinct_use.swift
@@ -55,7 +55,12 @@ doit()
 // CHECK: [[TYPE_COMPARISON_LABEL]]:
 // CHECK:   [[EQUAL_TYPE:%[0-9]+]] = icmp eq i8* bitcast (%swift.type* @"$sSiN" to i8*), [[ERASED_TYPE]]
 // CHECK:   [[EQUAL_TYPES:%[0-9]+]] = and i1 true, [[EQUAL_TYPE]]
-// CHECK:   br i1 [[EQUAL_TYPES]], label %[[EXIT_PRESPECIALIZED:[0-9]+]], label %[[EXIT_NORMAL:[0-9]+]]
+// CHECK:   [[ARGUMENT_BUFFER:%[0-9]+]] = bitcast i8* [[ERASED_TABLE]] to i8**
+// CHECK:   [[UNCAST_PROVIDED_PROTOCOL_DESCRIPTOR:%[0-9]+]] = load i8*, i8** [[ARGUMENT_BUFFER]], align 1
+// CHECK:   [[PROVIDED_PROTOCOL_DESCRIPTOR:%[0-9]+]] = bitcast i8* [[UNCAST_PROVIDED_PROTOCOL_DESCRIPTOR]] to %swift.protocol_conformance_descriptor*
+// CHECK:   [[EQUAL_DESCRIPTORS:%[0-9]+]] = call swiftcc i1 @swift_compareProtocolConformanceDescriptors(%swift.protocol_conformance_descriptor* [[PROVIDED_PROTOCOL_DESCRIPTOR]], %swift.protocol_conformance_descriptor* @"$sSi4main1PAAMc")
+// CHECK:   [[EQUAL_ARGUMENTS:%[0-9]+]] = and i1 [[EQUAL_TYPES]], [[EQUAL_DESCRIPTORS]]
+// CHECK:   br i1 [[EQUAL_ARGUMENTS]], label %[[EXIT_PRESPECIALIZED:[0-9]+]], label %[[EXIT_NORMAL:[0-9]+]]
 // CHECK: [[EXIT_PRESPECIALIZED]]:
 // CHECK:   ret %swift.metadata_response { %swift.type* getelementptr inbounds (%swift.full_type, %swift.full_type* bitcast (<{ i8**, [[INT]], %swift.type_descriptor*, %swift.type*, i8**, i32{{(, \[4 x i8\])?}}, i64 }>* @"$s4main5ValueVySiGMf" to %swift.full_type*), i32 0, i32 1), [[INT]] 0 }
 // CHECK: [[EXIT_NORMAL]]:

diff --git a/.../IRGen/prespecialized-metadata/struct-inmodule-1argument-2conformance-1distinct_use.swift b/.../IRGen/prespecialized-metadata/struct-inmodule-1argument-2conformance-1distinct_use.swift
@@ -60,7 +60,17 @@ doit()
 // CHECK: [[TYPE_COMPARISON_LABEL]]:
 // CHECK:   [[EQUAL_TYPE:%[0-9]+]] = icmp eq i8* bitcast (%swift.type* @"$sSiN" to i8*), [[ERASED_TYPE]]
 // CHECK:   [[EQUAL_TYPES:%[0-9]+]] = and i1 true, [[EQUAL_TYPE]]
-// CHECK:   br i1 [[EQUAL_TYPES]], label %[[EXIT_PRESPECIALIZED:[0-9]+]], label %[[EXIT_NORMAL:[0-9]+]]
+// CHECK:   [[UNERASED_TABLE_1:%[0-9]+]] = bitcast i8* [[ERASED_TABLE_1]] to i8**
+// CHECK:   [[UNCAST_PROVIDED_PROTOCOL_DESCRIPTOR_1:%[0-9]+]] = load i8*, i8** [[UNERASED_TABLE_1]], align 1
+// CHECK:   [[PROVIDED_PROTOCOL_DESCRIPTOR_1:%[0-9]+]] = bitcast i8* [[UNCAST_PROVIDED_PROTOCOL_DESCRIPTOR_1]] to %swift.protocol_conformance_descriptor*
+// CHECK:   [[EQUAL_DESCRIPTORS_1:%[0-9]+]] = call swiftcc i1 @swift_compareProtocolConformanceDescriptors(%swift.protocol_conformance_descriptor* [[PROVIDED_PROTOCOL_DESCRIPTOR_1]], %swift.protocol_conformance_descriptor* @"$sSi4main1PAAMc")
+// CHECK:   [[EQUAL_ARGUMENTS_1:%[0-9]+]] = and i1 [[EQUAL_TYPES]], [[EQUAL_DESCRIPTORS_1]]
+// CHECK:   [[UNERASED_TABLE_2:%[0-9]+]] = bitcast i8* [[ERASED_TABLE_2]] to i8**
+// CHECK:   [[UNCAST_PROVIDED_PROTOCOL_DESCRIPTOR_2:%[0-9]+]] = load i8*, i8** [[UNERASED_TABLE_2]], align 1
+// CHECK:   [[PROVIDED_PROTOCOL_DESCRIPTOR_2:%[0-9]+]] = bitcast i8* [[UNCAST_PROVIDED_PROTOCOL_DESCRIPTOR_2]] to %swift.protocol_conformance_descriptor*
+// CHECK:   [[EQUAL_DESCRIPTORS_2:%[0-9]+]] = call swiftcc i1 @swift_compareProtocolConformanceDescriptors(%swift.protocol_conformance_descriptor* [[PROVIDED_PROTOCOL_DESCRIPTOR_2]], %swift.protocol_conformance_descriptor* @"$sSi4main1QAAMc")
+// CHECK:   [[EQUAL_ARGUMENTS_2:%[0-9]+]] = and i1 [[EQUAL_ARGUMENTS_1]], [[EQUAL_DESCRIPTORS_2]]
+// CHECK:   br i1 [[EQUAL_ARGUMENTS_2]], label %[[EXIT_PRESPECIALIZED:[0-9]+]], label %[[EXIT_NORMAL:[0-9]+]]
 // CHECK: [[EXIT_PRESPECIALIZED]]:
 // CHECK:   ret %swift.metadata_response { %swift.type* getelementptr inbounds (%swift.full_type, %swift.full_type* bitcast (<{ i8**, [[INT]], %swift.type_descriptor*, %swift.type*, i8**, i8**, i32{{(, \[4 x i8\])?}}, i64 }>* @"$s4main5ValueVySiGMf" to %swift.full_type*), i32 0, i32 1), [[INT]] 0 }
 // CHECK: [[EXIT_NORMAL]]:

diff --git a/.../IRGen/prespecialized-metadata/struct-inmodule-1argument-3conformance-1distinct_use.swift b/.../IRGen/prespecialized-metadata/struct-inmodule-1argument-3conformance-1distinct_use.swift
@@ -64,7 +64,28 @@ doit()
 // CHECK:   %"load argument at index 0 from buffer" = load i8*, i8** [[ERASED_TYPE_ADDRESS]]
 // CHECK:   [[EQUAL_TYPE:%[0-9]+]] = icmp eq i8* bitcast (%swift.type* @"$sSiN" to i8*), %"load argument at index 0 from buffer"
 // CHECK:   [[EQUAL_TYPES:%[0-9]+]] = and i1 true, [[EQUAL_TYPE]]
-// CHECK:   br i1 [[EQUAL_TYPES]], label %[[EXIT_PRESPECIALIZED:[0-9]+]], label %[[EXIT_NORMAL:[0-9]+]]
+// CHECK:   [[POINTER_TO_ERASED_TABLE_1:%[0-9]+]] = getelementptr i8*, i8** %1, i64 1
+// CHECK:   [[ERASED_TABLE_1:%"load argument at index 1 from buffer"]] = load i8*, i8** [[POINTER_TO_ERASED_TABLE_1]], align 1
+// CHECK:   [[UNERASED_TABLE_1:%[0-9]+]] = bitcast i8* [[ERASED_TABLE_1]] to i8**
+// CHECK:   [[UNCAST_PROVIDED_PROTOCOL_DESCRIPTOR_1:%[0-9]+]] = load i8*, i8** [[UNERASED_TABLE_1]], align 1
+// CHECK:   [[PROVIDED_PROTOCOL_DESCRIPTOR_1:%[0-9]+]] = bitcast i8* [[UNCAST_PROVIDED_PROTOCOL_DESCRIPTOR_1]] to %swift.protocol_conformance_descriptor*
+// CHECK:   [[EQUAL_DESCRIPTORS_1:%[0-9]+]] = call swiftcc i1 @swift_compareProtocolConformanceDescriptors(%swift.protocol_conformance_descriptor* [[PROVIDED_PROTOCOL_DESCRIPTOR_1]], %swift.protocol_conformance_descriptor* @"$sSi4main1PAAMc")
+// CHECK:   [[EQUAL_ARGUMENTS_1:%[0-9]+]] = and i1 [[EQUAL_TYPES]], [[EQUAL_DESCRIPTORS_1]]
+// CHECK:   [[POINTER_TO_ERASED_TABLE_2:%[0-9]+]] = getelementptr i8*, i8** %1, i64 2
+// CHECK:   [[ERASED_TABLE_2:%"load argument at index 2 from buffer"]] = load i8*, i8** [[POINTER_TO_ERASED_TABLE_2]], align 1
+// CHECK:   [[UNERASED_TABLE_2:%[0-9]+]] = bitcast i8* [[ERASED_TABLE_2]] to i8**
+// CHECK:   [[UNCAST_PROVIDED_PROTOCOL_DESCRIPTOR_2:%[0-9]+]] = load i8*, i8** [[UNERASED_TABLE_2]], align 1
+// CHECK:   [[PROVIDED_PROTOCOL_DESCRIPTOR_2:%[0-9]+]] = bitcast i8* [[UNCAST_PROVIDED_PROTOCOL_DESCRIPTOR_2]] to %swift.protocol_conformance_descriptor*
+// CHECK:   [[EQUAL_DESCRIPTORS_2:%[0-9]+]] = call swiftcc i1 @swift_compareProtocolConformanceDescriptors(%swift.protocol_conformance_descriptor* [[PROVIDED_PROTOCOL_DESCRIPTOR_2]], %swift.protocol_conformance_descriptor* @"$sSi4main1QAAMc")
+// CHECK:   [[EQUAL_ARGUMENTS_2:%[0-9]+]] = and i1 [[EQUAL_ARGUMENTS_1]], [[EQUAL_DESCRIPTORS_2]]
+// CHECK:   [[POINTER_TO_ERASED_TABLE_3:%[0-9]+]] = getelementptr i8*, i8** %1, i64 3
+// CHECK:   [[ERASED_TABLE_3:%"load argument at index 3 from buffer"]] = load i8*, i8** [[POINTER_TO_ERASED_TABLE_3]], align 1
+// CHECK:   [[UNERASED_TABLE_3:%[0-9]+]] = bitcast i8* [[ERASED_TABLE_3]] to i8**
+// CHECK:   [[UNCAST_PROVIDED_PROTOCOL_DESCRIPTOR_3:%[0-9]+]] = load i8*, i8** [[UNERASED_TABLE_3]], align 1
+// CHECK:   [[PROVIDED_PROTOCOL_DESCRIPTOR_3:%[0-9]+]] = bitcast i8* [[UNCAST_PROVIDED_PROTOCOL_DESCRIPTOR_3]] to %swift.protocol_conformance_descriptor*
+// CHECK:   [[EQUAL_DESCRIPTORS_3:%[0-9]+]] = call swiftcc i1 @swift_compareProtocolConformanceDescriptors(%swift.protocol_conformance_descriptor* [[PROVIDED_PROTOCOL_DESCRIPTOR_3]], %swift.protocol_conformance_descriptor* @"$sSi4main1RAAMc")
+// CHECK:   [[EQUAL_ARGUMENTS_3:%[0-9]+]] = and i1 [[EQUAL_ARGUMENTS_2]], [[EQUAL_DESCRIPTORS_3]]
+// CHECK:   br i1 [[EQUAL_ARGUMENTS_3]], label %[[EXIT_PRESPECIALIZED:[0-9]+]], label %[[EXIT_NORMAL:[0-9]+]]
 // CHECK: [[EXIT_PRESPECIALIZED]]:
 // CHECK:   ret %swift.metadata_response { %swift.type* getelementptr inbounds (%swift.full_type, %swift.full_type* bitcast (<{ i8**, [[INT]], %swift.type_descriptor*, %swift.type*, i8**, i8**, i8**, i32{{(, \[4 x i8\])?}}, i64 }>* @"$s4main5ValueVySiGMf" to %swift.full_type*), i32 0, i32 1), [[INT]] 0 }
 // CHECK: [[EXIT_NORMAL]]:

diff --git a/.../IRGen/prespecialized-metadata/struct-inmodule-1argument-4conformance-1distinct_use.swift b/.../IRGen/prespecialized-metadata/struct-inmodule-1argument-4conformance-1distinct_use.swift
@@ -68,7 +68,35 @@ doit()
 // CHECK:   %"load argument at index 0 from buffer" = load i8*, i8** [[ERASED_TYPE_ADDRESS]]
 // CHECK:   [[EQUAL_TYPE:%[0-9]+]] = icmp eq i8* bitcast (%swift.type* @"$sSiN" to i8*), %"load argument at index 0 from buffer"
 // CHECK:   [[EQUAL_TYPES:%[0-9]+]] = and i1 true, [[EQUAL_TYPE]]
-// CHECK:   br i1 [[EQUAL_TYPES]], label %[[EXIT_PRESPECIALIZED:[0-9]+]], label %[[EXIT_NORMAL:[0-9]+]]
+// CHECK:   [[POINTER_TO_ERASED_TABLE_1:%[0-9]+]] = getelementptr i8*, i8** %1, i64 1
+// CHECK:   [[ERASED_TABLE_1:%"load argument at index 1 from buffer"]] = load i8*, i8** [[POINTER_TO_ERASED_TABLE_1]], align 1
+// CHECK:   [[UNERASED_TABLE_1:%[0-9]+]] = bitcast i8* [[ERASED_TABLE_1]] to i8**
+// CHECK:   [[UNCAST_PROVIDED_PROTOCOL_DESCRIPTOR_1:%[0-9]+]] = load i8*, i8** [[UNERASED_TABLE_1]], align 1
+// CHECK:   [[PROVIDED_PROTOCOL_DESCRIPTOR_1:%[0-9]+]] = bitcast i8* [[UNCAST_PROVIDED_PROTOCOL_DESCRIPTOR_1]] to %swift.protocol_conformance_descriptor*
+// CHECK:   [[EQUAL_DESCRIPTORS_1:%[0-9]+]] = call swiftcc i1 @swift_compareProtocolConformanceDescriptors(%swift.protocol_conformance_descriptor* [[PROVIDED_PROTOCOL_DESCRIPTOR_1]], %swift.protocol_conformance_descriptor* @"$sSi4main1PAAMc")
+// CHECK:   [[EQUAL_ARGUMENTS_1:%[0-9]+]] = and i1 [[EQUAL_TYPES]], [[EQUAL_DESCRIPTORS_1]]
+// CHECK:   [[POINTER_TO_ERASED_TABLE_2:%[0-9]+]] = getelementptr i8*, i8** %1, i64 2
+// CHECK:   [[ERASED_TABLE_2:%"load argument at index 2 from buffer"]] = load i8*, i8** [[POINTER_TO_ERASED_TABLE_2]], align 1
+// CHECK:   [[UNERASED_TABLE_2:%[0-9]+]] = bitcast i8* [[ERASED_TABLE_2]] to i8**
+// CHECK:   [[UNCAST_PROVIDED_PROTOCOL_DESCRIPTOR_2:%[0-9]+]] = load i8*, i8** [[UNERASED_TABLE_2]], align 1
+// CHECK:   [[PROVIDED_PROTOCOL_DESCRIPTOR_2:%[0-9]+]] = bitcast i8* [[UNCAST_PROVIDED_PROTOCOL_DESCRIPTOR_2]] to %swift.protocol_conformance_descriptor*
+// CHECK:   [[EQUAL_DESCRIPTORS_2:%[0-9]+]] = call swiftcc i1 @swift_compareProtocolConformanceDescriptors(%swift.protocol_conformance_descriptor* [[PROVIDED_PROTOCOL_DESCRIPTOR_2]], %swift.protocol_conformance_descriptor* @"$sSi4main1QAAMc")
+// CHECK:   [[EQUAL_ARGUMENTS_2:%[0-9]+]] = and i1 [[EQUAL_ARGUMENTS_1]], [[EQUAL_DESCRIPTORS_2]]
+// CHECK:   [[POINTER_TO_ERASED_TABLE_3:%[0-9]+]] = getelementptr i8*, i8** %1, i64 3
+// CHECK:   [[ERASED_TABLE_3:%"load argument at index 3 from buffer"]] = load i8*, i8** [[POINTER_TO_ERASED_TABLE_3]], align 1
+// CHECK:   [[UNERASED_TABLE_3:%[0-9]+]] = bitcast i8* [[ERASED_TABLE_3]] to i8**
+// CHECK:   [[UNCAST_PROVIDED_PROTOCOL_DESCRIPTOR_3:%[0-9]+]] = load i8*, i8** [[UNERASED_TABLE_3]], align 1
+// CHECK:   [[PROVIDED_PROTOCOL_DESCRIPTOR_3:%[0-9]+]] = bitcast i8* [[UNCAST_PROVIDED_PROTOCOL_DESCRIPTOR_3]] to %swift.protocol_conformance_descriptor*
+// CHECK:   [[EQUAL_DESCRIPTORS_3:%[0-9]+]] = call swiftcc i1 @swift_compareProtocolConformanceDescriptors(%swift.protocol_conformance_descriptor* [[PROVIDED_PROTOCOL_DESCRIPTOR_3]], %swift.protocol_conformance_descriptor* @"$sSi4main1RAAMc")
+// CHECK:   [[EQUAL_ARGUMENTS_3:%[0-9]+]] = and i1 [[EQUAL_ARGUMENTS_2]], [[EQUAL_DESCRIPTORS_3]]
+// CHECK:   [[POINTER_TO_ERASED_TABLE_4:%[0-9]+]] = getelementptr i8*, i8** %1, i64 4
+// CHECK:   [[ERASED_TABLE_4:%"load argument at index 4 from buffer"]] = load i8*, i8** [[POINTER_TO_ERASED_TABLE_4]], align 1
+// CHECK:   [[UNERASED_TABLE_4:%[0-9]+]] = bitcast i8* [[ERASED_TABLE_4]] to i8**
+// CHECK:   [[UNCAST_PROVIDED_PROTOCOL_DESCRIPTOR_4:%[0-9]+]] = load i8*, i8** [[UNERASED_TABLE_4]], align 1
+// CHECK:   [[PROVIDED_PROTOCOL_DESCRIPTOR_4:%[0-9]+]] = bitcast i8* [[UNCAST_PROVIDED_PROTOCOL_DESCRIPTOR_4]] to %swift.protocol_conformance_descriptor*
+// CHECK:   [[EQUAL_DESCRIPTORS_4:%[0-9]+]] = call swiftcc i1 @swift_compareProtocolConformanceDescriptors(%swift.protocol_conformance_descriptor* [[PROVIDED_PROTOCOL_DESCRIPTOR_4]], %swift.protocol_conformance_descriptor* @"$sSi4main1SAAMc")
+// CHECK:   [[EQUAL_ARGUMENTS_4:%[0-9]+]] = and i1 [[EQUAL_ARGUMENTS_3]], [[EQUAL_DESCRIPTORS_4]]
+// CHECK:   br i1 [[EQUAL_ARGUMENTS_4]], label %[[EXIT_PRESPECIALIZED:[0-9]+]], label %[[EXIT_NORMAL:[0-9]+]]
 // CHECK: [[EXIT_PRESPECIALIZED]]:
 // CHECK:   ret %swift.metadata_response { %swift.type* getelementptr inbounds (%swift.full_type, %swift.full_type* bitcast (<{ i8**, [[INT]], %swift.type_descriptor*, %swift.type*, i8**, i8**, i8**, i8**, i32{{(, \[4 x i8\])?}}, i64 }>* @"$s4main5ValueVySiGMf" to %swift.full_type*), i32 0, i32 1), [[INT]] 0 }
 // CHECK: [[EXIT_NORMAL]]: