Merge branch 'main' into mpokhylets/isolated-deinit

# Conflicts:
#	include/swift/Basic/Features.def
#	lib/AST/ASTPrinter.cpp
#	lib/AST/FeatureSet.cpp

Author: nickolas-pohilets

CMakeLists.txt

@@ -968,6 +968,13 @@ if(SWIFT_INCLUDE_TOOLS AND SWIFT_BUILD_SWIFT_SYNTAX)
   if(SWIFT_HOST_VARIANT_SDK MATCHES "LINUX|OPENBSD|FREEBSD" AND NOT BOOTSTRAPPING_MODE STREQUAL "HOSTTOOLS")
     message(WARNING "Force setting BOOTSTRAPPING=HOSTTOOLS because Swift parser integration is enabled")
     set(BOOTSTRAPPING_MODE "HOSTTOOLS")
+    if(NOT CMAKE_Swift_COMPILER)
+      message(SEND_ERROR "No Swift compiler found.\n"
+        "Tell CMake where to find the Swift compiler by setting either the "
+        "environment variable \"SWIFTC\" or the CMake cache entry "
+        "CMAKE_Swift_COMPILER to the full path of the compiler, or to the "
+        "compiler name if it is in the PATH")
+    endif()
   endif()
   add_definitions(-DSWIFT_BUILD_SWIFT_SYNTAX)
 endif()

README.md

@@ -13,7 +13,8 @@
 | **Ubuntu 20.04** | AArch64 |[![Build Status](https://ci.swift.org/job/oss-swift-package-ubuntu-20_04-aarch64/lastCompletedBuild/badge/icon)](https://ci.swift.org/job/oss-swift-package-ubuntu-20_04-aarch64)|
 | **Ubuntu 22.04** | x86_64 |[![Build Status](https://ci.swift.org/job/oss-swift-package-ubuntu-22_04/lastCompletedBuild/badge/icon)](https://ci.swift.org/job/oss-swift-package-ubuntu-22_04)|
 | **Ubuntu 22.04** | AArch64 |[![Build Status](https://ci.swift.org/job/oss-swift-package-ubuntu-22_04-aarch64/lastCompletedBuild/badge/icon)](https://ci.swift.org/job/oss-swift-package-ubuntu-22_04-aarch64)|
-| **CentOS 7** | x86_64 |[![Build Status](https://ci.swift.org/job/oss-swift-package-centos-7/lastCompletedBuild/badge/icon)](https://ci.swift.org/job/oss-swift-package-centos-7)|
+| **Ubuntu 24.04** | x86_64 |[![Build Status](https://ci.swift.org/job/oss-swift-package-ubuntu-24_04/lastCompletedBuild/badge/icon)](https://ci.swift.org/job/oss-swift-package-ubuntu-24_04)|
+| **Ubuntu 24.04** | AArch64 |[![Build Status](https://ci.swift.org/job/oss-swift-package-ubuntu-24_04-aarch64/lastCompletedBuild/badge/icon)](https://ci.swift.org/job/oss-swift-package-ubuntu-24_04-aarch64)|
 | **Amazon Linux 2** | x86_64 |[![Build Status](https://ci.swift.org/job/oss-swift-package-amazon-linux-2/lastCompletedBuild/badge/icon)](https://ci.swift.org/job/oss-swift-package-amazon-linux-2)|
 | **Amazon Linux 2** | AArch64 |[![Build Status](https://ci.swift.org/job/oss-swift-package-amazon-linux-2-aarch64/lastCompletedBuild/badge/icon)](https://ci.swift.org/job/oss-swift-package-amazon-linux-2-aarch64)|
 | **Universal Base Image 9** | x86_64 |[![Build Status](https://ci.swift.org/job/oss-swift-package-ubi-9/lastCompletedBuild/badge/icon)](https://ci.swift.org/job/oss-swift-package-ubi-9)|
@@ -103,7 +104,7 @@ script is used by swift.org's CI to produce snapshots and can allow for one to
 locally reproduce such builds for development or distribution purposes. A typical 
 invocation looks like the following:
 
-```
+```sh
   $ ./swift/utils/build-toolchain $BUNDLE_PREFIX
 ```
 
@@ -134,7 +135,7 @@ On macOS if one wants to install such a toolchain into Xcode:
 1. Untar and copy the toolchain to one of `/Library/Developer/Toolchains/` or
    `~/Library/Developer/Toolchains/`. E.g.:
 
-```
+```sh
   $ sudo tar -xzf swift-LOCAL-YYYY-MM-DD-a-osx.tar.gz -C /
   $ tar -xzf swift-LOCAL-YYYY-MM-DD-a-osx.tar.gz -C ~/
 ```
@@ -143,7 +144,7 @@ The script also generates an archive containing debug symbols which
 can be installed over the main archive allowing symbolication of any
 compiler crashes.
 
-```
+```sh
   $ sudo tar -xzf swift-LOCAL-YYYY-MM-DD-a-osx-symbols.tar.gz -C /
   $ tar -xzf swift-LOCAL-YYYY-MM-DD-a-osx-symbols.tar.gz -C ~/
 ```

SwiftCompilerSources/Sources/Optimizer/DataStructures/FunctionUses.swift

@@ -45,7 +45,7 @@ struct FunctionUses {
     var hasUnknownUses: Bool
 
     init(of function: Function) {
-      self.hasUnknownUses = function.isPossiblyUsedExternally || function.isAvailableExternally
+      self.hasUnknownUses = function.isPossiblyUsedExternally || function.isDefinedExternally
     }
 
     mutating func insert(_ inst: Instruction, _ uses: inout [Use]) {

SwiftCompilerSources/Sources/Optimizer/FunctionPasses/ClosureSpecialization.swift

@@ -119,7 +119,7 @@ let generalClosureSpecialization = FunctionPass(name: "experimental-swift-based-
 let autodiffClosureSpecialization = FunctionPass(name: "autodiff-closure-specialization") {
   (function: Function, context: FunctionPassContext) in
 
-  guard !function.isAvailableExternally,
+  guard !function.isDefinedExternally,
         function.isAutodiffVJP,
         function.blocks.singleElement != nil else {
     return
@@ -502,7 +502,7 @@ private func handleApplies(for rootClosure: SingleValueInstruction, callSiteMap:
       continue
     }
 
-    if callee.isAvailableExternally {
+    if callee.isDefinedExternally {
       continue
     }
 

SwiftCompilerSources/Sources/Optimizer/FunctionPasses/ComputeSideEffects.swift

@@ -27,7 +27,7 @@ import SIL
 let computeSideEffects = FunctionPass(name: "compute-side-effects") {
   (function: Function, context: FunctionPassContext) in
 
-  if function.isAvailableExternally {
+  if function.isDefinedExternally {
     // We cannot assume anything about function, which are defined in another module,
     // even if the serialized SIL of its body is available in the current module.
     // If the other module was compiled with library evolution, the implementation

SwiftCompilerSources/Sources/Optimizer/ModulePasses/MandatoryPerformanceOptimizations.swift

@@ -118,6 +118,16 @@ private func optimize(function: Function, _ context: FunctionPassContext, _ modu
           context.erase(instructionIncludingDebugUses: iem)
         }
 
+      case let fri as FunctionRefInst:
+        // Mandatory de-virtualization and mandatory inlining might leave referenced functions in "serialized"
+        // functions with wrong linkage. Fix this by making the referenced function public.
+        // It's not great, because it can prevent dead code elimination. But it's only a rare case.
+        if function.serializedKind != .notSerialized,
+           !fri.referencedFunction.hasValidLinkageForFragileRef(function.serializedKind)
+        {
+          fri.referencedFunction.set(linkage: .public, moduleContext)
+        }
+
       default:
         break
       }
@@ -153,6 +163,8 @@ private func specializeVTableAndAddEntriesToWorklist(for type: Type, in function
 
 private func inlineAndDevirtualize(apply: FullApplySite, alreadyInlinedFunctions: inout Set<PathFunctionTuple>,
                                    _ context: FunctionPassContext, _ simplifyCtxt: SimplifyContext) {
+  // De-virtualization and inlining in/into a "serialized" function might create function references to functions
+  // with wrong linkage. We need to fix this later (see handling of FunctionRefInst in `optimize`).
   if simplifyCtxt.tryDevirtualize(apply: apply, isMandatory: true) != nil {
     return
   }
@@ -166,9 +178,7 @@ private func inlineAndDevirtualize(apply: FullApplySite, alreadyInlinedFunctions
     return
   }
 
-  if apply.canInline &&
-     shouldInline(apply: apply, callee: callee, alreadyInlinedFunctions: &alreadyInlinedFunctions)
-  {
+  if shouldInline(apply: apply, callee: callee, alreadyInlinedFunctions: &alreadyInlinedFunctions) {
     if apply.inliningCanInvalidateStackNesting  {
       simplifyCtxt.notifyInvalidatedStackNesting()
     }
@@ -196,9 +206,14 @@ private func removeUnusedMetatypeInstructions(in function: Function, _ context:
 
 private func shouldInline(apply: FullApplySite, callee: Function, alreadyInlinedFunctions: inout Set<PathFunctionTuple>) -> Bool {
   if callee.isTransparent {
+    precondition(callee.hasOwnership, "transparent functions should have ownership at this stage of the pipeline")
     return true
   }
 
+  if !apply.canInline {
+    return false
+  }
+
   if apply is BeginApplyInst {
     // Avoid co-routines because they might allocate (their context).
     return true

SwiftCompilerSources/Sources/Optimizer/ModulePasses/ReadOnlyGlobalVariables.swift

@@ -35,7 +35,7 @@ let readOnlyGlobalVariablesPass = ModulePass(name: "read-only-global-variables")
   }
 
   for g in moduleContext.globalVariables {
-    if !g.isAvailableExternally,
+    if !g.isDefinedExternally,
        !g.isPossiblyUsedExternally,
        !g.isLet,
        !writtenGlobals.contains(g) {

SwiftCompilerSources/Sources/Optimizer/PassManager/ModulePassContext.swift

@@ -171,3 +171,9 @@ extension GlobalVariable {
     bridged.setLet(value)
   }
 }
+
+extension Function {
+  func set(linkage: Linkage, _ context: ModulePassContext) {
+    bridged.setLinkage(linkage.bridged)
+  }
+}

SwiftCompilerSources/Sources/Optimizer/Utilities/LocalVariableUtils.swift

@@ -420,7 +420,8 @@ extension LocalVariableAccessWalker: AddressUseVisitor {
   mutating func leafAddressUse(of operand: Operand) -> WalkResult {
     switch operand.instruction {
     case is StoringInstruction, is SourceDestAddrInstruction, is DestroyAddrInst, is DeinitExistentialAddrInst,
-         is InjectEnumAddrInst, is TupleAddrConstructorInst, is InitBlockStorageHeaderInst, is PackElementSetInst:
+         is InjectEnumAddrInst, is SwitchEnumAddrInst, is TupleAddrConstructorInst, is InitBlockStorageHeaderInst,
+         is PackElementSetInst:
       // Handle instructions that initialize both temporaries and local variables.
       visit(LocalVariableAccess(.store, operand))
     case is DeallocStackInst:

SwiftCompilerSources/Sources/SIL/CMakeLists.txt

@@ -20,6 +20,7 @@ add_swift_compiler_module(SIL
     FunctionConvention.swift
     GlobalVariable.swift
     Instruction.swift
+    Linkage.swift
     Location.swift
     Operand.swift
     Registration.swift