Remove the -resilience-bypass flag and functionality.

LLDB no longer depends on it.

rdar://problem/48018240

Author: adrian-prantl

include/swift/AST/IRGenOptions.h

@@ -172,9 +172,6 @@ class IRGenOptions {
   /// expression evaluator.
   unsigned ForcePublicLinkage : 1;
 
-  /// Bypass resilience when accessing resilient frameworks.
-  unsigned EnableResilienceBypass : 1;
-
   /// Force lazy initialization of class metadata
   /// Used on Windows to avoid cross-module references.
   unsigned LazyInitializeClassMetadata : 1;
@@ -230,21 +227,20 @@ class IRGenOptions {
         Verify(true), OptMode(OptimizationMode::NotSet),
         Sanitizers(OptionSet<SanitizerKind>()),
         DebugInfoLevel(IRGenDebugInfoLevel::None),
-        DebugInfoFormat(IRGenDebugInfoFormat::None),
-        UseJIT(false), IntegratedREPL(false),
-        DisableLLVMOptzns(false), DisableSwiftSpecificLLVMOptzns(false),
-        DisableLLVMSLPVectorizer(false), DisableFPElim(true), Playground(false),
-        EmitStackPromotionChecks(false), PrintInlineTree(false),
-        EmbedMode(IRGenEmbedMode::None), HasValueNamesSetting(false),
-        ValueNames(false), EnableReflectionMetadata(true),
-        EnableReflectionNames(true), EnableAnonymousContextMangledNames(false),
-        ForcePublicLinkage(false),
-        EnableResilienceBypass(false), LazyInitializeClassMetadata(false),
+        DebugInfoFormat(IRGenDebugInfoFormat::None), UseJIT(false),
+        IntegratedREPL(false), DisableLLVMOptzns(false),
+        DisableSwiftSpecificLLVMOptzns(false), DisableLLVMSLPVectorizer(false),
+        DisableFPElim(true), Playground(false), EmitStackPromotionChecks(false),
+        PrintInlineTree(false), EmbedMode(IRGenEmbedMode::None),
+        HasValueNamesSetting(false), ValueNames(false),
+        EnableReflectionMetadata(true), EnableReflectionNames(true),
+        EnableAnonymousContextMangledNames(false), ForcePublicLinkage(false),
+        LazyInitializeClassMetadata(false),
         LazyInitializeProtocolConformances(false), DisableLegacyTypeInfo(false),
         UseIncrementalLLVMCodeGen(true), UseSwiftCall(false),
         GenerateProfile(false), EnableDynamicReplacementChaining(false),
-        DisableRoundTripDebugTypes(false),
-        CmdArgs(), SanitizeCoverage(llvm::SanitizerCoverageOptions()),
+        DisableRoundTripDebugTypes(false), CmdArgs(),
+        SanitizeCoverage(llvm::SanitizerCoverageOptions()),
         TypeInfoFilter(TypeInfoDumpFilter::All) {}
 
   // Get a hash of all options which influence the llvm compilation but are not

include/swift/Option/FrontendOptions.td

@@ -517,9 +517,6 @@ def prebuilt_module_cache_path_EQ :
   Joined<["-"], "prebuilt-module-cache-path=">,
   Alias<prebuilt_module_cache_path>;
 
-def enable_resilience_bypass : Flag<["-"], "enable-resilience-bypass">,
-   HelpText<"Completely bypass resilience when accessing types in resilient frameworks">;
-
 def force_public_linkage : Flag<["-"], "force-public-linkage">,
    HelpText<"Force public linkage for private symbols. Used by LLDB.">;
 

lib/Frontend/CompilerInvocation.cpp

@@ -1082,10 +1082,6 @@ static bool ParseIRGenArgs(IRGenOptions &Opts, ArgList &Args,
     Opts.EnableReflectionNames = false;
   }
 
-  if (Args.hasArg(OPT_enable_resilience_bypass)) {
-    Opts.EnableResilienceBypass = true;
-  }
-
   if (Args.hasArg(OPT_force_public_linkage)) {
     Opts.ForcePublicLinkage = true;
   }

lib/IRGen/GenType.cpp

@@ -1169,14 +1169,6 @@ static bool doesPlatformSupportObjCMetadataUpdateCallback(
 TypeConverter::TypeConverter(IRGenModule &IGM)
   : IGM(IGM),
     FirstType(invalidTypeInfo()) {
-  // FIXME: In LLDB, everything is completely fragile, so that IRGen can query
-  // the size of resilient types. Of course this is not the right long term
-  // solution, because it won't work once the swiftmodule file is not in
-  // sync with the binary module. Once LLDB can calculate type layouts at
-  // runtime (using remote mirrors or some other mechanism), we can remove this.
-  if (IGM.IRGen.Opts.EnableResilienceBypass)
-    LoweringMode = Mode::CompletelyFragile;
-
   const auto &Triple = IGM.Context.LangOpts.Target;
 
   SupportsObjCMetadataUpdateCallback =

lib/IRGen/MetadataRequest.cpp

@@ -659,24 +659,6 @@ bool irgen::isTypeMetadataAccessTrivial(IRGenModule &IGM, CanType type) {
 
     auto expansion = ResilienceExpansion::Maximal;
 
-    // Normally, if a value type is known to have a fixed layout to us, we will
-    // have emitted fully initialized metadata for it, including a payload size
-    // field for enum metadata for example, allowing the type metadata to be
-    // used in other resilience domains without initialization.
-    //
-    // However, when -enable-resilience-bypass is on, we might be using a value
-    // type from another module built with resilience enabled. In that case, the
-    // type looks like it has fixed size to us, since we're bypassing resilience,
-    // but the metadata still requires runtime initialization, so its incorrect
-    // to reference it directly.
-    //
-    // While unconditionally using minimal expansion is correct, it is not as
-    // efficient as it should be, so only do so if -enable-resilience-bypass is on.
-    //
-    // FIXME: All of this goes away once lldb supports resilience.
-    if (IGM.IRGen.Opts.EnableResilienceBypass)
-      expansion = ResilienceExpansion::Minimal;
-
     // Resiliently-sized metadata access always requires an accessor.
     return (IGM.getTypeInfoForUnlowered(type).isFixedSize(expansion));
   }

test/DebugInfo/struct_resilience.swift

@@ -6,11 +6,9 @@
 // RUN:   -emit-module-path=%t/resilient_struct.swiftmodule \
 // RUN:   -module-name=resilient_struct %S/../Inputs/resilient_struct.swift
 //
-// RUN: %target-swift-frontend -g -I %t -emit-ir -enable-library-evolution %s  -o - \
-// RUN:  | %FileCheck %s
+// RUN: %target-swift-frontend -g -I %t -emit-ir -enable-library-evolution %s \
+// RUN:    -o - | %FileCheck %s
 //
-// RUN: %target-swift-frontend -g -I %t -emit-ir -enable-library-evolution %s -o - \
-// RUN:    -enable-resilience-bypass | %FileCheck %s --check-prefix=CHECK-LLDB
 import resilient_struct
 
 // CHECK-LABEL: define{{.*}} swiftcc void @"$s17struct_resilience9takesSizeyy010resilient_A00D0VF"(%swift.opaque* noalias nocapture)
@@ -29,17 +27,9 @@ func f() {
   // CHECK-SAME:                        metadata !DIExpression(DW_OP_deref))
   // CHECK: %[[S1:.*]] = alloca i8,
   // CHECK: store i8* %[[S1]], i8** %[[ADDR]]
-
-  // CHECK-LLDB: %[[ADDR:.*]] = alloca %T16resilient_struct4SizeV
-  // CHECK-LLDB: call void @llvm.dbg.declare(metadata %T16resilient_struct4SizeV* %[[ADDR]],
-  // CHECK-LLDB-SAME:                        metadata ![[V1:[0-9]+]],
-  // CHECK-LLDB-SAME:                        metadata !DIExpression())
 }
 f()
 
 // CHECK: ![[TY:[0-9]+]] = !DICompositeType(tag: DW_TAG_structure_type, name: "Size",
 
 // CHECK: ![[V1]] = !DILocalVariable(name: "s1", {{.*}}type: ![[TY]])
-
-// CHECK-LLDB: ![[TY:[0-9]+]] = !DICompositeType(tag: DW_TAG_structure_type, name: "Size",
-// CHECK-LLDB: ![[V1]] = !DILocalVariable(name: "s1", {{.*}}type: ![[TY]])