Swift 5.5.3 patched to compile for PowerPC 32-bit

swift-5.5.3-ppc.patch

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7a3cc3af07a..d0963c1804f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -285,7 +285,7 @@ set(SWIFT_ANDROID_DEPLOY_DEVICE_PATH "" CACHE STRING
 #
 
 foreach(sdk ANDROID;FREEBSD;LINUX;WINDOWS;HAIKU;WASI)
-  foreach(arch aarch64;armv6;armv7;i686;powerpc64;powerpc64le;s390x;wasm32;x86_64)
+  foreach(arch aarch64;armv6;armv7;i686;powerpc;powerpc64;powerpc64le;s390x;wasm32;x86_64)
     set(SWIFT_${sdk}_${arch}_ICU_UC "" CACHE STRING
         "Path to a directory containing the icuuc library for ${sdk}")
     set(SWIFT_${sdk}_${arch}_ICU_UC_INCLUDE "" CACHE STRING
@@ -632,6 +632,8 @@ else()
     endif()
   elseif("${CMAKE_SYSTEM_PROCESSOR}" STREQUAL "ppc64")
     set(SWIFT_HOST_VARIANT_ARCH_default "powerpc64")
+  elseif("${CMAKE_SYSTEM_PROCESSOR}" STREQUAL "ppc")
+    set(SWIFT_HOST_VARIANT_ARCH_default "powerpc")
   elseif("${CMAKE_SYSTEM_PROCESSOR}" STREQUAL "ppc64le")
     set(SWIFT_HOST_VARIANT_ARCH_default "powerpc64le")
   elseif("${CMAKE_SYSTEM_PROCESSOR}" STREQUAL "s390x")
diff --git a/cmake/modules/SwiftConfigureSDK.cmake b/cmake/modules/SwiftConfigureSDK.cmake
index 8a32c12abb1..2fc53820388 100644
--- a/cmake/modules/SwiftConfigureSDK.cmake
+++ b/cmake/modules/SwiftConfigureSDK.cmake
@@ -337,7 +337,7 @@ macro(configure_sdk_unix name architectures)
       if("${prefix}" STREQUAL "LINUX")
         if(arch MATCHES "(armv6|armv7)")
           set(SWIFT_SDK_LINUX_ARCH_${arch}_TRIPLE "${arch}-unknown-linux-gnueabihf")
-        elseif(arch MATCHES "(aarch64|i686|powerpc64|powerpc64le|s390x|x86_64)")
+        elseif(arch MATCHES "(aarch64|i686|powerpc|powerpc64|powerpc64le|s390x|x86_64)")
           set(SWIFT_SDK_LINUX_ARCH_${arch}_TRIPLE "${arch}-unknown-linux-gnu")
         else()
           message(FATAL_ERROR "unknown arch for ${prefix}: ${arch}")
diff --git a/cmake/modules/SwiftSetIfArchBitness.cmake b/cmake/modules/SwiftSetIfArchBitness.cmake
index fa29d77fe26..8880828bfd1 100644
--- a/cmake/modules/SwiftSetIfArchBitness.cmake
+++ b/cmake/modules/SwiftSetIfArchBitness.cmake
@@ -14,7 +14,8 @@ function(set_if_arch_bitness var_name)
      "${SIA_ARCH}" STREQUAL "armv7k" OR
      "${SIA_ARCH}" STREQUAL "arm64_32" OR
      "${SIA_ARCH}" STREQUAL "armv7s" OR
-     "${SIA_ARCH}" STREQUAL "wasm32")
+     "${SIA_ARCH}" STREQUAL "wasm32" OR
+     "${SIA_ARCH}" STREQUAL "powerpc")
     set("${var_name}" "${SIA_CASE_32_BIT}" PARENT_SCOPE)
   elseif("${SIA_ARCH}" STREQUAL "x86_64" OR
          "${SIA_ARCH}" STREQUAL "amd64" OR
diff --git a/lib/Basic/LangOptions.cpp b/lib/Basic/LangOptions.cpp
index 041d6a637b1..fa65dfa30ff 100644
--- a/lib/Basic/LangOptions.cpp
+++ b/lib/Basic/LangOptions.cpp
@@ -61,6 +61,7 @@ static const SupportedConditionalValue SupportedConditionalCompilationArches[] =
   "arm64_32",
   "i386",
   "x86_64",
+  "powerpc",
   "powerpc64",
   "powerpc64le",
   "s390x",
@@ -311,6 +312,9 @@ std::pair<bool, bool> LangOptions::setTarget(llvm::Triple triple) {
       addPlatformConditionValue(PlatformConditionKind::Arch, "arm64");
     }
     break;
+  case llvm::Triple::ArchType::ppc:
+    addPlatformConditionValue(PlatformConditionKind::Arch, "powerpc");
+    break;
   case llvm::Triple::ArchType::ppc64:
     addPlatformConditionValue(PlatformConditionKind::Arch, "powerpc64");
     break;
diff --git a/lib/IRGen/SwiftTargetInfo.cpp b/lib/IRGen/SwiftTargetInfo.cpp
index 81c0fce41bc..97b70d6d75c 100644
--- a/lib/IRGen/SwiftTargetInfo.cpp
+++ b/lib/IRGen/SwiftTargetInfo.cpp
@@ -144,6 +144,13 @@ static void configureARM(IRGenModule &IGM, const llvm::Triple &triple,
   setToMask(target.IsObjCPointerBit, 32, SWIFT_ABI_ARM_IS_OBJC_BIT);
 }
 
+/// Configures target-specific information for powerpc platforms.
+static void configurePowerPC(IRGenModule &IGM, const llvm::Triple &triple,
+                               SwiftTargetInfo &target) {
+  setToMask(target.PointerSpareBits, 32,
+            SWIFT_ABI_POWERPC_SWIFT_SPARE_BITS_MASK);
+}
+
 /// Configures target-specific information for powerpc64 platforms.
 static void configurePowerPC64(IRGenModule &IGM, const llvm::Triple &triple,
                                SwiftTargetInfo &target) {
@@ -220,6 +227,10 @@ SwiftTargetInfo SwiftTargetInfo::get(IRGenModule &IGM) {
     else
       configureARM64(IGM, triple, target);
     break;
+  
+  case llvm::Triple::ppc:
+    configurePowerPC(IGM, triple, target);
+    break;
 
   case llvm::Triple::ppc64:
   case llvm::Triple::ppc64le:
diff --git a/stdlib/public/SwiftShims/HeapObject.h b/stdlib/public/SwiftShims/HeapObject.h
index 5e165fd3d4e..cea7477a31e 100644
--- a/stdlib/public/SwiftShims/HeapObject.h
+++ b/stdlib/public/SwiftShims/HeapObject.h
@@ -202,6 +202,9 @@ static_assert(alignof(HeapObject) == alignof(void*),
       (defined(__arm64__) && (__POINTER_WIDTH__ == 32))
 #define _swift_abi_SwiftSpareBitsMask                                          \
   (__swift_uintptr_t) SWIFT_ABI_ARM_SWIFT_SPARE_BITS_MASK
+#elif defined(__powerpc__)
+#define _swift_abi_SwiftSpareBitsMask                                          \
+  (__swift_uintptr_t) SWIFT_ABI_POWERPC_SWIFT_SPARE_BITS_MASK
 #else
 #define _swift_abi_SwiftSpareBitsMask                                          \
   (__swift_uintptr_t) SWIFT_ABI_DEFAULT_SWIFT_SPARE_BITS_MASK
diff --git a/stdlib/public/SwiftShims/RefCount.h b/stdlib/public/SwiftShims/RefCount.h
index 5499de8d562..bee126cdbcd 100644
--- a/stdlib/public/SwiftShims/RefCount.h
+++ b/stdlib/public/SwiftShims/RefCount.h
@@ -1319,7 +1319,12 @@ class HeapObjectSideTableEntry {
 
   public:
   HeapObjectSideTableEntry(HeapObject *newObject)
-    : object(newObject), refCounts()
+    : object(newObject), 
+#if __arm__ || __powerpc__
+   refCounts(SideTableRefCounts::Initialized)
+#else
+   refCounts()
+#endif
   { }
 
 #pragma clang diagnostic push
diff --git a/stdlib/public/SwiftShims/System.h b/stdlib/public/SwiftShims/System.h
index 9656bf69fe1..896bc6a4bef 100644
--- a/stdlib/public/SwiftShims/System.h
+++ b/stdlib/public/SwiftShims/System.h
@@ -173,6 +173,11 @@
 #define SWIFT_ABI_ARM64_OBJC_WEAK_REFERENCE_MARKER_VALUE \
   (1<<SWIFT_ABI_ARM64_OBJC_NUM_RESERVED_LOW_BITS)
 
+/*********************************** powerpc ********************************/
+
+// Heap objects are pointer-aligned, so the low two bits are unused.
+#define SWIFT_ABI_POWERPC_SWIFT_SPARE_BITS_MASK 0x00000003U
+
 /*********************************** powerpc64 ********************************/
 
 // Heap objects are pointer-aligned, so the low three bits are unused.
diff --git a/stdlib/public/core/AtomicInt.swift.gyb b/stdlib/public/core/AtomicInt.swift.gyb
index a66212f4b35..56fed2cb117 100644
--- a/stdlib/public/core/AtomicInt.swift.gyb
+++ b/stdlib/public/core/AtomicInt.swift.gyb
@@ -65,7 +65,7 @@ internal func _swift_stdlib_atomicCompareExchangeStrongInt(
   object target: UnsafeMutablePointer<Int>,
   expected: UnsafeMutablePointer<Int>,
   desired: Int) -> Bool {
-#if arch(i386) || arch(arm) || arch(arm64_32) || arch(wasm32)
+#if arch(i386) || arch(arm) || arch(arm64_32) || arch(wasm32) || arch(powerpc)
   let (oldValue, won) = Builtin.cmpxchg_seqcst_seqcst_Int32(
     target._rawValue, expected.pointee._value, desired._value)
 #elseif arch(x86_64) || arch(arm64) || arch(powerpc64) || arch(powerpc64le) || arch(s390x)
@@ -82,7 +82,7 @@ internal func _swift_stdlib_atomicCompareExchangeStrongInt(
 public // Existing uses outside stdlib
 func _swift_stdlib_atomicLoadInt(
   object target: UnsafeMutablePointer<Int>) -> Int {
-#if arch(i386) || arch(arm) || arch(arm64_32) || arch(wasm32)
+#if arch(i386) || arch(arm) || arch(arm64_32) || arch(wasm32) || arch(powerpc)
   let value = Builtin.atomicload_seqcst_Int32(target._rawValue)
   return Int(value)
 #elseif arch(x86_64) || arch(arm64) || arch(powerpc64) || arch(powerpc64le) || arch(s390x)
@@ -95,7 +95,7 @@ func _swift_stdlib_atomicLoadInt(
 internal func _swift_stdlib_atomicStoreInt(
   object target: UnsafeMutablePointer<Int>,
   desired: Int) {
-#if arch(i386) || arch(arm) || arch(arm64_32) || arch(wasm32)
+#if arch(i386) || arch(arm) || arch(arm64_32) || arch(wasm32) || arch(powerpc)
   Builtin.atomicstore_seqcst_Int32(target._rawValue, desired._value)
 #elseif arch(x86_64) || arch(arm64) || arch(powerpc64) || arch(powerpc64le) || arch(s390x)
   Builtin.atomicstore_seqcst_Int64(target._rawValue, desired._value)
@@ -111,7 +111,7 @@ func _swift_stdlib_atomicFetch${operation}Int(
   object target: UnsafeMutablePointer<Int>,
   operand: Int) -> Int {
   let rawTarget = UnsafeMutableRawPointer(target)
-#if arch(i386) || arch(arm) || arch(arm64_32) || arch(wasm32)
+#if arch(i386) || arch(arm) || arch(arm64_32) || arch(wasm32) || arch(powerpc)
   let value = _swift_stdlib_atomicFetch${operation}Int32(
     object: rawTarget.assumingMemoryBound(to: Int32.self),
     operand: Int32(operand))
diff --git a/stdlib/public/core/Builtin.swift b/stdlib/public/core/Builtin.swift
index 29c17834204..b58be8cb332 100644
--- a/stdlib/public/core/Builtin.swift
+++ b/stdlib/public/core/Builtin.swift
@@ -390,7 +390,7 @@ internal var _objectPointerLowSpareBitShift: UInt {
     }
 }
 
-#if arch(i386) || arch(arm) || arch(wasm32) || arch(powerpc64) || arch(
+#if arch(i386) || arch(arm) || arch(wasm32) || arch(powerpc) || arch(powerpc64) || arch(
   powerpc64le) || arch(s390x) || arch(arm64_32)
 @inlinable
 internal var _objectPointerIsObjCBit: UInt {
diff --git a/stdlib/public/stubs/MathStubs.cpp b/stdlib/public/stubs/MathStubs.cpp
index 8d0617089ca..1f0c8693c29 100644
--- a/stdlib/public/stubs/MathStubs.cpp
+++ b/stdlib/public/stubs/MathStubs.cpp
@@ -112,7 +112,7 @@ __muloti4(ti_int a, ti_int b, int* overflow)
 // lowered to instructions as though MSVC had generated.  There does not seem to
 // be a MSVC provided multiply with overflow detection that I can see, but this
 // avoids an unnecessary dependency on compiler-rt for a single function.
-#if (defined(__linux__) && (defined(__arm__) || defined(__i386__))) || defined(_WIN32)
+#if (defined(__linux__) && (defined(__arm__) || defined(__i386__) || defined(__powerpc__))) || defined(_WIN32)
 
 // Similar to above, but with mulodi4.  Perhaps this is
 // something that shouldn't be done, and is a bandaid over
diff --git a/test/Inputs/clang-importer-sdk/swift-modules/CoreGraphics.swift b/test/Inputs/clang-importer-sdk/swift-modules/CoreGraphics.swift
index dbb14cebc2a..dbb0ccc70c7 100644
--- a/test/Inputs/clang-importer-sdk/swift-modules/CoreGraphics.swift
+++ b/test/Inputs/clang-importer-sdk/swift-modules/CoreGraphics.swift
@@ -6,7 +6,7 @@ public func == (lhs: CGPoint, rhs: CGPoint) -> Bool {
 }
 
 public struct CGFloat {
-#if arch(i386) || arch(arm) || arch(arm64_32)
+#if arch(i386) || arch(arm) || arch(arm64_32) || arch(powerpc)
   public typealias UnderlyingType = Float
 #elseif arch(x86_64) || arch(arm64) || arch(powerpc64le) || arch(s390x)
   public typealias UnderlyingType = Double
diff --git a/test/Interpreter/builtin_bridge_object.swift b/test/Interpreter/builtin_bridge_object.swift
index 24808a956b5..15682c34187 100644
--- a/test/Interpreter/builtin_bridge_object.swift
+++ b/test/Interpreter/builtin_bridge_object.swift
@@ -13,7 +13,7 @@ class C {
   deinit { print("deallocated") }
 }
 
-#if arch(i386) || arch(arm) || arch(arm64_32)
+#if arch(i386) || arch(arm) || arch(arm64_32) || arch(powerpc)
 
 // We have no ObjC tagged pointers, and two low spare bits due to alignment.
 let NATIVE_SPARE_BITS: UInt = 0x0000_0003
diff --git a/test/stdlib/Inputs/FloatingPointConversion.swift.gyb b/test/stdlib/Inputs/FloatingPointConversion.swift.gyb
index e95d1ca5b5f..433c2327338 100644
--- a/test/stdlib/Inputs/FloatingPointConversion.swift.gyb
+++ b/test/stdlib/Inputs/FloatingPointConversion.swift.gyb
@@ -134,7 +134,7 @@ FloatingPointConversionFailures.test("${OtherFloat}To${Self}Conversion/AlwaysSuc
 
 %  end # for in all_floating_point_types (Other)
 
-#if arch(i386) || arch(arm) || arch(arm64_32)
+#if arch(i386) || arch(arm) || arch(arm64_32) || arch(powerpc)
 % int_types = all_integer_types(32)
 #elseif arch(x86_64) || arch(arm64) || arch(powerpc64) || arch(powerpc64le) || arch(s390x)
 % int_types = all_integer_types(64)
diff --git a/test/stdlib/Runtime.swift.gyb b/test/stdlib/Runtime.swift.gyb
index 5ef0578aac3..73bc8abc373 100644
--- a/test/stdlib/Runtime.swift.gyb
+++ b/test/stdlib/Runtime.swift.gyb
@@ -683,7 +683,7 @@ Reflection.test("multiprotocolTypes") {
 var BitTwiddlingTestSuite = TestSuite("BitTwiddling")
 
 BitTwiddlingTestSuite.test("_pointerSize") {
-#if arch(i386) || arch(arm) || arch(arm64_32)
+#if arch(i386) || arch(arm) || arch(arm64_32) || arch(powerpc)
   expectEqual(4, MemoryLayout<Optional<AnyObject>>.size)
 #elseif arch(x86_64) || arch(arm64) || arch(powerpc64) || arch(powerpc64le) || arch(s390x)
   expectEqual(8, MemoryLayout<Optional<AnyObject>>.size)
@@ -707,7 +707,7 @@ BitTwiddlingTestSuite.test("_isPowerOf2/Int") {
   expectTrue(_isPowerOf2(asInt(2)))
   expectFalse(_isPowerOf2(asInt(3)))
   expectTrue(_isPowerOf2(asInt(1024)))
-#if arch(i386) || arch(arm) || arch(arm64_32)
+#if arch(i386) || arch(arm) || arch(arm64_32) || arch(powerpc)
   // Not applicable to 32-bit architectures.
 #elseif arch(x86_64) || arch(arm64) || arch(powerpc64) || arch(powerpc64le) || arch(s390x)
   expectTrue(_isPowerOf2(asInt(0x8000_0000)))
diff --git a/test/stdlib/UnsafePointer.swift.gyb b/test/stdlib/UnsafePointer.swift.gyb
index 3e91a273e5d..285f1b09ba9 100644
--- a/test/stdlib/UnsafePointer.swift.gyb
+++ b/test/stdlib/UnsafePointer.swift.gyb
@@ -400,7 +400,7 @@ ${SelfName}TestSuite.test("customMirror") {
   let ptr = ${SelfType}(bitPattern: reallyBigInt)!
   let mirror = ptr.customMirror
   expectEqual(1, mirror.children.count)
-#if arch(i386) || arch(arm) || arch(arm64_32)
+#if arch(i386) || arch(arm) || arch(arm64_32) || arch(powerpc)
   expectEqual("18446744071562067968", String(describing: mirror.children.first!.1))
 #elseif arch(x86_64) || arch(arm64) || arch(powerpc64) || arch(powerpc64le) || arch(s390x)
   expectEqual("9223372036854775808", String(describing: mirror.children.first!.1))
@@ -415,7 +415,7 @@ ${SelfName}TestSuite.test("customPlaygroundQuickLook") {
   let reallyBigInt: UInt = UInt(Int.max) + 1
   let ptr = ${SelfType}(bitPattern: reallyBigInt)!
   if case let .text(desc) = ptr.customPlaygroundQuickLook {
-#if arch(i386) || arch(arm) || arch(arm64_32)
+#if arch(i386) || arch(arm) || arch(arm64_32) || arch(powerpc)
     expectEqual("${SelfName}(0xFFFFFFFF80000000)", desc)
 #elseif arch(x86_64) || arch(arm64) || arch(powerpc64) || arch(powerpc64le) || arch(s390x)
     expectEqual("${SelfName}(0x8000000000000000)", desc)
diff --git a/utils/build-script-impl b/utils/build-script-impl
index aa72cfbf06d..b03e1cc8813 100755
--- a/utils/build-script-impl
+++ b/utils/build-script-impl
@@ -418,6 +418,7 @@ function verify_host_is_supported() {
       | linux-armv6             \
       | linux-armv7             \
       | linux-aarch64           \
+      | linux-powerpc           \
       | linux-powerpc64         \
       | linux-powerpc64le       \
       | linux-s390x             \
diff --git a/utils/swift-bench.py b/utils/swift-bench.py
index 0ec7343c7eb..a61b1de0c81 100644
--- a/utils/swift-bench.py
+++ b/utils/swift-bench.py
@@ -146,7 +146,7 @@ func _opaqueGetInt64(x: Int) -> Int
 
 @inline(never)
 public func getInt(x: Int) -> Int {
-#if arch(i386) || arch(arm) || arch(arm64_32)
+#if arch(i386) || arch(arm) || arch(arm64_32)|| arch(powerpc)
   return _opaqueGetInt32(x)
 #elseif arch(x86_64) || arch(arm64) || arch(powerpc64) || \
 arch(powerpc64le) || arch(s390x)
diff --git a/utils/swift_build_support/swift_build_support/targets.py b/utils/swift_build_support/swift_build_support/targets.py
index 2cb86fb3571..2fb70404851 100644
--- a/utils/swift_build_support/swift_build_support/targets.py
+++ b/utils/swift_build_support/swift_build_support/targets.py
@@ -227,6 +227,7 @@ class StdlibDeploymentTarget(object):
         "armv6",
         "armv7",
         "aarch64",
+        "powerpc",
         "powerpc64",
         "powerpc64le",
         "s390x"])
@@ -303,6 +304,8 @@ class StdlibDeploymentTarget(object):
                 return StdlibDeploymentTarget.Linux.armv6
             elif machine == 'aarch64':
                 return StdlibDeploymentTarget.Linux.aarch64
+            elif machine == 'ppc':
+                return StdlibDeploymentTarget.Linux.powerpc
             elif machine == 'ppc64':
                 return StdlibDeploymentTarget.Linux.powerpc64
             elif machine == 'ppc64le':