swiftlang · compnerd · Apr 13, 2018 · Apr 12, 2018
diff --git a/stdlib/public/stubs/CMakeLists.txt b/stdlib/public/stubs/CMakeLists.txt
@@ -5,6 +5,7 @@ set(swift_stubs_sources
     KeyPaths.cpp
     LibcShims.cpp
     Stubs.cpp
+    MathStubs.cpp
 )
 set(swift_stubs_objc_sources
     Availability.mm
@@ -23,15 +24,21 @@ set(swift_stubs_c_compile_flags ${SWIFT_RUNTIME_CORE_CXX_FLAGS})
 list(APPEND swift_stubs_c_compile_flags -DswiftCore_EXPORTS)
 list(APPEND swift_stubs_c_compile_flags -I${SWIFT_SOURCE_DIR}/include)
 
-add_swift_library(swiftStdlibStubs OBJECT_LIBRARY TARGET_LIBRARY
-  ${swift_stubs_sources}
-  ${swift_stubs_objc_sources}
-  ${swift_stubs_unicode_normalization_sources}
-  C_COMPILE_FLAGS ${swift_stubs_c_compile_flags}
-  LINK_FLAGS ${SWIFT_RUNTIME_CORE_LINK_FLAGS}
-  INSTALL_IN_COMPONENT stdlib)
+add_swift_library(swiftStdlibStubs
+                  OBJECT_LIBRARY TARGET_LIBRARY
+                    ${swift_stubs_sources}
+                    ${swift_stubs_objc_sources}
+                    ${swift_stubs_unicode_normalization_sources}
+                  C_COMPILE_FLAGS
+                    ${swift_stubs_c_compile_flags}
+                  LINK_FLAGS
+                    ${SWIFT_RUNTIME_CORE_LINK_FLAGS}
+                  INSTALL_IN_COMPONENT
+                    stdlib)
 
 if(CMAKE_SYSTEM_NAME STREQUAL "Darwin")
-  set_property(SOURCE SwiftNativeNSXXXBaseARC.m APPEND_STRING PROPERTY COMPILE_FLAGS
-    "-fobjc-arc")
+  set_property(SOURCE
+                 SwiftNativeNSXXXBaseARC.m
+               APPEND_STRING PROPERTY COMPILE_FLAGS
+                 "-fobjc-arc")
 endif()
diff --git a/stdlib/public/stubs/MathStubs.cpp b/stdlib/public/stubs/MathStubs.cpp
@@ -0,0 +1,146 @@
+//===--- MathStubs.cpp - Swift Language Runtime Stubs ---------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+//===----------------------------------------------------------------------===//
+//
+// Math stubs for functions which should be defined in the core standard
+// library, but are difficult or impossible to write in Swift at the
+// moment.
+//
+//===----------------------------------------------------------------------===//
+
+#include "../SwiftShims/Visibility.h"
+
+#include <climits>
+#include <cstdlib>
+
+#if __has_attribute(__mode__)
+#define SWIFT_MODE_DI __attribute__((__mode__(DI)))
+#define SWIFT_MODE_TI __attribute__((__mode__(TI)))
+#else
+#define SWIFT_MODE_DI
+#define SWIFT_MODE_TI
+#endif
+
+typedef int di_int SWIFT_MODE_DI;
+typedef int ti_int SWIFT_MODE_TI;
+
+extern "C" {
+
+// Although this builtin is provided by clang rt builtins,
+// it isn't provided by libgcc, which is the default
+// runtime library on Linux, even when compiling with clang.
+// This implementation is copied here to avoid a new dependency
+// on compiler-rt on Linux.
+// FIXME: rdar://14883575 Libcompiler_rt omits muloti4
+#if (defined(__linux__) && defined(__x86_64__)) || \
+    (defined(__linux__) && defined(__aarch64__)) || \
+    (defined(__linux__) && defined(__powerpc64__)) || \
+    (defined(__linux__) && defined(__s390x__)) || \
+    (defined(__ANDROID__) && defined(__arm64__))
+
+SWIFT_RUNTIME_STDLIB_INTERFACE
+ti_int
+__muloti4(ti_int a, ti_int b, int* overflow)
+{
+    const int N = (int)(sizeof(ti_int) * CHAR_BIT);
+    const ti_int MIN = (ti_int)1 << (N-1);
+    const ti_int MAX = ~MIN;
+    *overflow = 0;
+    ti_int result = a * b;
+    if (a == MIN)
+    {
+        if (b != 0 && b != 1)
+            *overflow = 1;
+        return result;
+    }
+    if (b == MIN)
+    {
+        if (a != 0 && a != 1)
+            *overflow = 1;
+        return result;
+    }
+    ti_int sa = a >> (N - 1);
+    ti_int abs_a = (a ^ sa) - sa;
+    ti_int sb = b >> (N - 1);
+    ti_int abs_b = (b ^ sb) - sb;
+    if (abs_a < 2 || abs_b < 2)
+        return result;
+    if (sa == sb)
+    {
+        if (abs_a > MAX / abs_b)
+            *overflow = 1;
+    }
+    else
+    {
+        if (abs_a > MIN / -abs_b)
+            *overflow = 1;
+    }
+    return result;
+}
+
+#endif
+
+// FIXME: ideally we would have a slow path here for Windows which would be
+// 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(_WIN32)
+
+// Similar to above, but with mulodi4.  Perhaps this is
+// something that shouldn't be done, and is a bandaid over
+// some other lower-level architecture issue that I'm
+// missing.  Perhaps relevant bug report:
+// FIXME: https://llvm.org/bugs/show_bug.cgi?id=14469
+
+SWIFT_RUNTIME_STDLIB_INTERFACE
+di_int
+__mulodi4(di_int a, di_int b, int* overflow)
+{
+    const int N = (int)(sizeof(di_int) * CHAR_BIT);
+    const di_int MIN = (di_int)1 << (N-1);
+    const di_int MAX = ~MIN;
+    *overflow = 0;
+    di_int result = a * b;
+    if (a == MIN)
+    {
+        if (b != 0 && b != 1)
+            *overflow = 1;
+        return result;
+    }
+    if (b == MIN)
+    {
+        if (a != 0 && a != 1)
+            *overflow = 1;
+        return result;
+    }
+    di_int sa = a >> (N - 1);
+    di_int abs_a = (a ^ sa) - sa;
+    di_int sb = b >> (N - 1);
+    di_int abs_b = (b ^ sb) - sb;
+    if (abs_a < 2 || abs_b < 2)
+        return result;
+    if (sa == sb)
+    {
+        if (abs_a > MAX / abs_b)
+            *overflow = 1;
+    }
+    else
+    {
+        if (abs_a > MIN / -abs_b)
+            *overflow = 1;
+    }
+    return result;
+}
+
+#endif
+
+}
+
diff --git a/stdlib/public/stubs/Stubs.cpp b/stdlib/public/stubs/Stubs.cpp
@@ -330,120 +330,6 @@ swift::swift_stdlib_readLine_stdin(unsigned char **LinePtr) {
 #endif
 }
 
-
-// Although this builtin is provided by clang rt builtins,
-// it isn't provided by libgcc, which is the default
-// runtime library on Linux, even when compiling with clang.
-// This implementation is copied here to avoid a new dependency
-// on compiler-rt on Linux.
-// FIXME: rdar://14883575 Libcompiler_rt omits muloti4
-#if (defined(__linux__) && defined(__x86_64__)) || \
-    (defined(__linux__) && defined(__aarch64__)) || \
-    (defined(__linux__) && defined(__powerpc64__)) || \
-    (defined(__linux__) && defined(__s390x__)) || \
-    (defined(__ANDROID__) && defined(__arm64__))
-
-typedef int ti_int __attribute__((__mode__(TI)));
-SWIFT_RUNTIME_STDLIB_INTERFACE
-ti_int
-__muloti4(ti_int a, ti_int b, int* overflow)
-{
-    const int N = (int)(sizeof(ti_int) * CHAR_BIT);
-    const ti_int MIN = (ti_int)1 << (N-1);
-    const ti_int MAX = ~MIN;
-    *overflow = 0;
-    ti_int result = a * b;
-    if (a == MIN)
-    {
-        if (b != 0 && b != 1)
-            *overflow = 1;
-        return result;
-    }
-    if (b == MIN)
-    {
-        if (a != 0 && a != 1)
-            *overflow = 1;
-        return result;
-    }
-    ti_int sa = a >> (N - 1);
-    ti_int abs_a = (a ^ sa) - sa;
-    ti_int sb = b >> (N - 1);
-    ti_int abs_b = (b ^ sb) - sb;
-    if (abs_a < 2 || abs_b < 2)
-        return result;
-    if (sa == sb)
-    {
-        if (abs_a > MAX / abs_b)
-            *overflow = 1;
-    }
-    else
-    {
-        if (abs_a > MIN / -abs_b)
-            *overflow = 1;
-    }
-    return result;
-}
-
-#endif
-
-// FIXME: ideally we would have a slow path here for Windows which would be
-// 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(_WIN32)
-// Similar to above, but with mulodi4.  Perhaps this is
-// something that shouldn't be done, and is a bandaid over
-// some other lower-level architecture issue that I'm
-// missing.  Perhaps relevant bug report:
-// FIXME: https://llvm.org/bugs/show_bug.cgi?id=14469
-#if __has_attribute(__mode__)
-#define SWIFT_MODE_DI __attribute__((__mode__(DI)))
-#else
-#define SWIFT_MODE_DI
-#endif
-
-typedef int di_int SWIFT_MODE_DI;
-SWIFT_RUNTIME_STDLIB_INTERFACE
-di_int
-__mulodi4(di_int a, di_int b, int* overflow)
-{
-    const int N = (int)(sizeof(di_int) * CHAR_BIT);
-    const di_int MIN = (di_int)1 << (N-1);
-    const di_int MAX = ~MIN;
-    *overflow = 0;
-    di_int result = a * b;
-    if (a == MIN)
-    {
-        if (b != 0 && b != 1)
-            *overflow = 1;
-        return result;
-    }
-    if (b == MIN)
-    {
-        if (a != 0 && a != 1)
-            *overflow = 1;
-        return result;
-    }
-    di_int sa = a >> (N - 1);
-    di_int abs_a = (a ^ sa) - sa;
-    di_int sb = b >> (N - 1);
-    di_int abs_b = (b ^ sb) - sb;
-    if (abs_a < 2 || abs_b < 2)
-        return result;
-    if (sa == sb)
-    {
-        if (abs_a > MAX / abs_b)
-            *overflow = 1;
-    }
-    else
-    {
-        if (abs_a > MIN / -abs_b)
-            *overflow = 1;
-    }
-    return result;
-}
-#endif
-
 #if defined(__CYGWIN__) || defined(_WIN32)
   #define strcasecmp _stricmp
 #endif