Merge pull request #41 from apple/master

[pull] swiftwasm from apple:master

cmake/modules/AddSwift.cmake

@@ -708,14 +708,6 @@ function(_add_swift_lipo_target)
   endif()
 endfunction()
 
-function(swift_target_link_search_directories target directories)
-  set(STLD_FLAGS "")
-  foreach(directory ${directories})
-    set(STLD_FLAGS "${STLD_FLAGS} \"${CMAKE_LIBRARY_PATH_FLAG}${directory}\"")
-  endforeach()
-  set_property(TARGET ${target} APPEND_STRING PROPERTY LINK_FLAGS ${STLD_FLAGS})
-endfunction()
-
 # Add a single variant of a new Swift library.
 #
 # Usage:
@@ -892,22 +884,10 @@ function(_add_swift_library_single target name)
   if(SWIFT_EMBED_BITCODE_SECTION AND NOT SWIFTLIB_SINGLE_DONT_EMBED_BITCODE)
     if("${SWIFTLIB_SINGLE_SDK}" STREQUAL "IOS" OR "${SWIFTLIB_SINGLE_SDK}" STREQUAL "TVOS" OR "${SWIFTLIB_SINGLE_SDK}" STREQUAL "WATCHOS")
       list(APPEND SWIFTLIB_SINGLE_C_COMPILE_FLAGS "-fembed-bitcode")
-      list(APPEND SWIFTLIB_SINGLE_LINK_FLAGS "-Xlinker" "-bitcode_bundle" "-Xlinker" "-lto_library" "-Xlinker" "${LLVM_LIBRARY_DIR}/libLTO.dylib")
-      # If we are asked to hide symbols, pass the obfuscation flag to libLTO.
-      if (SWIFT_EMBED_BITCODE_SECTION_HIDE_SYMBOLS)
-        list(APPEND SWIFTLIB_SINGLE_LINK_FLAGS "-Xlinker" "-bitcode_hide_symbols")
-      endif()
       set(embed_bitcode_arg EMBED_BITCODE)
     endif()
   endif()
 
-  if(${SWIFTLIB_SINGLE_SDK} IN_LIST SWIFT_APPLE_PLATFORMS)
-    list(APPEND SWIFTLIB_SINGLE_LINK_FLAGS "-Xlinker" "-compatibility_version" "-Xlinker" "1")
-    if (SWIFT_COMPILER_VERSION)
-      list(APPEND SWIFTLIB_SINGLE_LINK_FLAGS "-Xlinker" "-current_version" "-Xlinker" "${SWIFT_COMPILER_VERSION}" )
-    endif()
-  endif()
-
   if(XCODE)
     string(REGEX MATCHALL "/[^/]+" split_path ${CMAKE_CURRENT_SOURCE_DIR})
     list(GET split_path -1 dir)
@@ -1281,23 +1261,6 @@ function(_add_swift_library_single target name)
         "${swift_module_dependency_target}"
         ${LLVM_COMMON_DEPENDS})
 
-  # HACK: On some systems or build directory setups, CMake will not find static
-  # archives of Clang libraries in the Clang build directory, and it will pass
-  # them as '-lclangFoo'.  Some other logic in CMake would reorder libraries
-  # specified with this syntax, which breaks linking.
-  set(prefixed_link_libraries)
-  foreach(dep ${SWIFTLIB_SINGLE_LINK_LIBRARIES})
-    if("${dep}" MATCHES "^clang")
-      if("${SWIFT_HOST_VARIANT_SDK}" STREQUAL "WINDOWS")
-        set(dep "${LLVM_LIBRARY_OUTPUT_INTDIR}/${dep}.lib")
-      else()
-        set(dep "${LLVM_LIBRARY_OUTPUT_INTDIR}/lib${dep}.a")
-      endif()
-    endif()
-    list(APPEND prefixed_link_libraries "${dep}")
-  endforeach()
-  set(SWIFTLIB_SINGLE_LINK_LIBRARIES "${prefixed_link_libraries}")
-
   if("${libkind}" STREQUAL "SHARED")
     target_link_libraries("${target}" PRIVATE ${SWIFTLIB_SINGLE_LINK_LIBRARIES})
   elseif("${libkind}" STREQUAL "OBJECT")
@@ -1463,17 +1426,32 @@ function(_add_swift_library_single target name)
     set(PLIST_INFO_BUILD_VERSION)
   endif()
 
-  # Convert variables to space-separated strings.
-  _list_escape_for_shell("${c_compile_flags}" c_compile_flags)
-  _list_escape_for_shell("${link_flags}" link_flags)
-
   # Set compilation and link flags.
-  set_property(TARGET "${target}" APPEND_STRING PROPERTY
-      COMPILE_FLAGS " ${c_compile_flags}")
-  set_property(TARGET "${target}" APPEND_STRING PROPERTY
-      LINK_FLAGS " ${link_flags}")
-  set_property(TARGET "${target}" APPEND PROPERTY LINK_LIBRARIES ${link_libraries})
-  swift_target_link_search_directories("${target}" "${library_search_directories}")
+  target_compile_options(${target} PRIVATE
+    ${c_compile_flags})
+  target_link_options(${target} PRIVATE
+    ${link_flags})
+  if(${SWIFTLIB_SINGLE_SDK} IN_LIST SWIFT_APPLE_PLATFORMS)
+    target_link_options(${target} PRIVATE
+      "LINKER:-compatibility_version,1")
+    if(SWIFT_COMPILER_VERSION)
+      target_link_options(${target} PRIVATE
+        "LINKER:-current_version,${SWIFT_COMPILER_VERSION}")
+    endif()
+    # Include LLVM Bitcode slices for iOS, Watch OS, and Apple TV OS device libraries.
+    if(SWIFT_EMBED_BITCODE_SECTION AND NOT SWIFTLIB_SINGLE_DONT_EMBED_BITCODE)
+      if(${SWIFTLIB_SINGLE_SDK} MATCHES "(I|TV|WATCH)OS")
+        target_link_options(${target} PRIVATE
+          "LINKER:-bitcode_bundle"
+          $<$<BOOL:SWIFT_EMBED_BITCODE_SECTION_HIDE_SYMBOLS>:"LINKER:-bitcode_hide_symbols">
+          "LINKER:-lto_library,${LLVM_LIBRARY_DIR}/libLTO.dylib")
+      endif()
+    endif()
+  endif()
+  target_link_libraries(${target} PRIVATE
+    ${link_libraries})
+  target_link_directories(${target} PRIVATE
+    ${library_search_directories})
 
   # Adjust the linked libraries for windows targets.  On Windows, the link is
   # performed against the import library, and the runtime uses the dll.  Not
@@ -1523,8 +1501,8 @@ function(_add_swift_library_single target name)
   endif()
 
   if(target_static)
-    set_property(TARGET "${target_static}" APPEND_STRING PROPERTY
-        COMPILE_FLAGS " ${c_compile_flags}")
+    target_link_options(${target_static} PRIVATE
+      ${c_compile_flags})
     # FIXME: The fallback paths here are going to be dynamic libraries.
 
     if(SWIFTLIB_INSTALL_WITH_SHARED)
@@ -1536,7 +1514,8 @@ function(_add_swift_library_single target name)
         "${search_base_dir}/${SWIFTLIB_SINGLE_SUBDIR}"
         "${SWIFT_NATIVE_SWIFT_TOOLS_PATH}/../lib/swift/${SWIFTLIB_SINGLE_SUBDIR}"
         "${SWIFT_NATIVE_SWIFT_TOOLS_PATH}/../lib/swift/${SWIFT_SDK_${SWIFTLIB_SINGLE_SDK}_LIB_SUBDIR}")
-    swift_target_link_search_directories("${target_static}" "${library_search_directories}")
+    target_link_directories(${target_static} PRIVATE
+      ${library_search_directories})
     target_link_libraries("${target_static}" PRIVATE
         ${SWIFTLIB_SINGLE_PRIVATE_LINK_LIBRARIES})
   endif()
@@ -2637,16 +2616,14 @@ function(_add_swift_executable_single name)
         ${SWIFTEXE_SINGLE_DEPENDS})
   llvm_update_compile_flags("${name}")
 
-  # Convert variables to space-separated strings.
-  _list_escape_for_shell("${c_compile_flags}" c_compile_flags)
-  _list_escape_for_shell("${link_flags}" link_flags)
-
-  set_property(TARGET ${name} APPEND_STRING PROPERTY
-      COMPILE_FLAGS " ${c_compile_flags}")
-  swift_target_link_search_directories("${name}" "${library_search_directories}")
-  set_property(TARGET ${name} APPEND_STRING PROPERTY
-      LINK_FLAGS " ${link_flags}")
-  set_property(TARGET ${name} APPEND PROPERTY LINK_LIBRARIES ${link_libraries})
+  target_compile_options(${name} PRIVATE
+    ${c_compile_flags})
+  target_link_directories(${name} PRIVATE
+    ${library_search_directories})
+  target_link_options(${name} PRIVATE
+    ${link_flags})
+  target_link_libraries(${name} PRIVATE
+    ${link_libraries})
   if (SWIFT_PARALLEL_LINK_JOBS)
     set_property(TARGET ${name} PROPERTY JOB_POOL_LINK swift_link_job_pool)
   endif()

cmake/modules/SwiftList.cmake

@@ -38,15 +38,6 @@ function(_list_add_string_suffix input_list suffix result_var_name)
   set("${result_var_name}" "${result}" PARENT_SCOPE)
 endfunction()
 
-function(_list_escape_for_shell input_list result_var_name)
-  set(result "")
-  foreach(element ${input_list})
-    string(REPLACE " " "\\ " element "${element}")
-    set(result "${result}${element} ")
-  endforeach()
-  set("${result_var_name}" "${result}" PARENT_SCOPE)
-endfunction()
-
 function(list_replace input_list old new)
   set(replaced_list)
   foreach(item ${${input_list}})

include/swift/SILOptimizer/PassManager/Passes.def

@@ -200,6 +200,8 @@ PASS(LICM, "licm",
      "Loop Invariant Code Motion")
 PASS(LateCodeMotion, "late-codemotion",
      "Late Code Motion with Release Hoisting")
+PASS(LateDeadFunctionElimination, "late-deadfuncelim",
+     "Late Dead Function Elimination")
 PASS(LateInliner, "late-inline",
      "Late Function Inlining")
 PASS(LoopCanonicalizer, "loop-canonicalizer",

lib/SILOptimizer/IPO/DeadFunctionElimination.cpp

@@ -90,6 +90,8 @@ class FunctionLivenessComputation {
 
   llvm::SmallPtrSet<void *, 32> AliveFunctionsAndTables;
 
+  bool keepExternalWitnessTablesAlive;
+
   /// Checks is a function is alive, e.g. because it is visible externally.
   bool isAnchorFunction(SILFunction *F) {
 
@@ -148,6 +150,11 @@ class FunctionLivenessComputation {
   /// Marks all contained functions and witness tables of a witness table as
   /// alive.
   void makeAlive(SILWitnessTable *WT) {
+    if (isAvailableExternally(WT->getLinkage()) &&
+        !keepExternalWitnessTablesAlive) {
+      return;
+    }
+
     LLVM_DEBUG(llvm::dbgs() << "    scan witness table " << WT->getName()
                             << '\n');
 
@@ -393,8 +400,10 @@ class FunctionLivenessComputation {
   }
 
 public:
-  FunctionLivenessComputation(SILModule *module) :
-    Module(module) {}
+  FunctionLivenessComputation(SILModule *module,
+                              bool keepExternalWitnessTablesAlive) :
+    Module(module),
+    keepExternalWitnessTablesAlive(keepExternalWitnessTablesAlive) {}
 
   /// The main entry point of the optimization.
   bool findAliveFunctions() {
@@ -635,8 +644,8 @@ class DeadFunctionElimination : FunctionLivenessComputation {
   }
 
 public:
-  DeadFunctionElimination(SILModule *module)
-      : FunctionLivenessComputation(module) {}
+  DeadFunctionElimination(SILModule *module, bool keepExternalWitnessTablesAlive)
+      : FunctionLivenessComputation(module, keepExternalWitnessTablesAlive) {}
 
   /// The main entry point of the optimization.
   void eliminateFunctions(SILModuleTransform *DFEPass) {
@@ -693,6 +702,13 @@ class DeadFunctionElimination : FunctionLivenessComputation {
 namespace {
 
 class SILDeadFuncElimination : public SILModuleTransform {
+
+private:
+  bool isLateDFE;
+
+public:
+  SILDeadFuncElimination(bool isLateDFE) : isLateDFE(isLateDFE) { }
+
   void run() override {
     LLVM_DEBUG(llvm::dbgs() << "Running DeadFuncElimination\n");
 
@@ -703,15 +719,20 @@ class SILDeadFuncElimination : public SILModuleTransform {
     // can eliminate such functions.
     getModule()->invalidateSILLoaderCaches();
 
-    DeadFunctionElimination deadFunctionElimination(getModule());
+    DeadFunctionElimination deadFunctionElimination(getModule(),
+                                /*keepExternalWitnessTablesAlive*/ !isLateDFE);
     deadFunctionElimination.eliminateFunctions(this);
   }
 };
 
 } // end anonymous namespace
 
 SILTransform *swift::createDeadFunctionElimination() {
-  return new SILDeadFuncElimination();
+  return new SILDeadFuncElimination(/*isLateDFE*/ false);
+}
+
+SILTransform *swift::createLateDeadFunctionElimination() {
+  return new SILDeadFuncElimination(/*isLateDFE*/ true);
 }
 
 void swift::performSILDeadFunctionElimination(SILModule *M) {

lib/SILOptimizer/PassManager/PassPipeline.cpp

@@ -522,7 +522,9 @@ static void addLateLoopOptPassPipeline(SILPassPipelinePlan &P) {
   P.startPipeline("LateLoopOpt");
 
   // Delete dead code and drop the bodies of shared functions.
-  P.addDeadFunctionElimination();
+  // Also, remove externally available witness tables. They are not needed
+  // anymore after the last devirtualizer run.
+  P.addLateDeadFunctionElimination();
 
   // Perform the final lowering transformations.
   P.addCodeSinking();

lib/SymbolGraphGen/CMakeLists.txt

@@ -7,7 +7,7 @@ add_swift_host_library(swiftSymbolGraphGen STATIC
   SymbolGraphGen.cpp
   SymbolGraphASTWalker.cpp)
 
-target_link_libraries(swiftSymbolGraphGen
+target_link_libraries(swiftSymbolGraphGen PRIVATE
   swiftAST
   swiftFrontend
   swiftMarkup)

test/SIL/Serialization/init_existential_inst_deserializes_witness_tables.swift

@@ -1,6 +1,6 @@
 // RUN: %empty-directory(%t)
 // RUN: %target-swift-frontend -sil-inline-threshold 0 %S/Inputs/init_existential_inst_deserializes_witness_tables_input.swift -o %t/Swift.swiftmodule -emit-module -parse-as-library -parse-stdlib -module-link-name swiftCore -module-name Swift -O
-// RUN: %target-swift-frontend -I %t -O %s -emit-sil -o - | %FileCheck %s
+// RUN: %target-swift-frontend -I %t -O %s -Xllvm -sil-disable-pass=late-deadfuncelim -emit-sil -o - | %FileCheck %s
 
 // CHECK: sil_witness_table public_external X: P module Swift {
 

test/SILOptimizer/devirt_opaque_witness.swift

@@ -1,6 +1,6 @@
 // RUN: %empty-directory(%t)
 // RUN: %target-swift-frontend -emit-module -emit-module-path %t/opaque_conformance.swiftmodule -primary-file %S/Inputs/opaque_conformance.swift
-// RUN: %target-swift-frontend -O -emit-sil -primary-file %s -I %t | %FileCheck %s
+// RUN: %target-swift-frontend -O -emit-sil -primary-file %s -I %t -Xllvm -sil-disable-pass=late-deadfuncelim | %FileCheck %s
 
 import opaque_conformance
 

test/SILOptimizer/sil_witness_tables_external_witnesstable.swift

@@ -1,13 +1,19 @@
 // RUN: %empty-directory(%t)
 // RUN: %target-swift-frontend -emit-module %S/Inputs/sil_witness_tables_external_input.swift -o %t/Swift.swiftmodule -parse-stdlib -parse-as-library -module-name Swift -module-link-name swiftCore
-// RUN: %target-swift-frontend -O -I %t %s -emit-sil | %FileCheck %s
+// RUN: %target-swift-frontend -O -I %t %s -Xllvm -sil-disable-pass=late-deadfuncelim -emit-sil | %FileCheck %s
+// RUN: %target-swift-frontend -O -I %t %s -emit-sil | %FileCheck -check-prefix=CHECK-DFE %s
 
 import Swift
 
 // Make sure the specializer produces an external witness table.
 //
 // CHECK: sil_witness_table public_external X: P module Swift {
 
+// Also check that late dead-function-elimination is removing externally
+// available witness tables.
+//
+// CHECK-DFE-NOT: sil_witness_table public_external
+
 func doSomething<T : P>(_ t : T) -> Y {
   return t.doSomething()
 }

tools/SourceKit/cmake/modules/AddSwiftSourceKit.cmake

@@ -70,17 +70,15 @@ function(add_sourcekit_default_compiler_flags target)
     LINK_LIBRARIES_VAR_NAME link_libraries
     LIBRARY_SEARCH_DIRECTORIES_VAR_NAME library_search_directories)
 
-  # Convert variables to space-separated strings.
-  _list_escape_for_shell("${c_compile_flags}" c_compile_flags)
-  _list_escape_for_shell("${link_flags}" link_flags)
-
   # Set compilation and link flags.
-  set_property(TARGET "${target}" APPEND_STRING PROPERTY
-      COMPILE_FLAGS " ${c_compile_flags} -fblocks")
-  set_property(TARGET "${target}" APPEND_STRING PROPERTY
-      LINK_FLAGS " ${link_flags}")
-  set_property(TARGET "${target}" APPEND PROPERTY LINK_LIBRARIES ${link_libraries})
-  swift_target_link_search_directories("${target}" "${library_search_directories}")
+  target_compile_options(${target} PRIVATE
+    -fblocks)
+  target_link_options(${target} PRIVATE
+    ${link_flags})
+  target_link_directories(${target} PRIVATE
+    ${library_search_directories})
+  target_link_libraries(${target} PRIVATE
+    ${link_libraries})
 endfunction()
 
 # Add a new SourceKit library.