diff options
Diffstat (limited to 'clang/lib/Frontend/InitPreprocessor.cpp')
| -rw-r--r-- | clang/lib/Frontend/InitPreprocessor.cpp | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/clang/lib/Frontend/InitPreprocessor.cpp b/clang/lib/Frontend/InitPreprocessor.cpp index c1b9d57f09d..93d49b0563b 100644 --- a/clang/lib/Frontend/InitPreprocessor.cpp +++ b/clang/lib/Frontend/InitPreprocessor.cpp @@ -202,6 +202,20 @@ static void DefineExactWidthIntType(TargetInfo::IntType Ty, ConstSuffix); } +/// Get the value the ATOMIC_*_LOCK_FREE macro should have for a type with +/// the specified properties. +static const char *getLockFreeValue(unsigned TypeWidth, unsigned TypeAlign, + unsigned InlineWidth) { + // Fully-aligned, power-of-2 sizes no larger than the inline + // width will be inlined as lock-free operations. + if (TypeWidth == TypeAlign && (TypeWidth & (TypeWidth - 1)) == 0 && + TypeWidth <= InlineWidth) + return "2"; // "always lock free" + // We cannot be certain what operations the lib calls might be + // able to implement as lock-free on future processors. + return "1"; // "sometimes lock free" +} + /// \brief Add definitions required for a smooth interaction between /// Objective-C++ automated reference counting and libstdc++ (4.2). static void AddObjCXXARCLibstdcxxDefines(const LangOptions &LangOpts, @@ -521,6 +535,32 @@ static void InitializePredefinedMacros(const TargetInfo &TI, else Builder.defineMacro("__GNUC_STDC_INLINE__"); + // The value written by __atomic_test_and_set. + // FIXME: This is target-dependent. + Builder.defineMacro("__GCC_ATOMIC_TEST_AND_SET_TRUEVAL", "1"); + + // Used by libstdc++ to implement ATOMIC_<foo>_LOCK_FREE. + unsigned InlineWidthBits = TI.getMaxAtomicInlineWidth(); +#define DEFINE_LOCK_FREE_MACRO(TYPE, Type) \ + Builder.defineMacro("__GCC_ATOMIC_" #TYPE "_LOCK_FREE", \ + getLockFreeValue(TI.get##Type##Width(), \ + TI.get##Type##Align(), \ + InlineWidthBits)); + DEFINE_LOCK_FREE_MACRO(BOOL, Bool); + DEFINE_LOCK_FREE_MACRO(CHAR, Char); + DEFINE_LOCK_FREE_MACRO(CHAR16_T, Char16); + DEFINE_LOCK_FREE_MACRO(CHAR32_T, Char32); + DEFINE_LOCK_FREE_MACRO(WCHAR_T, WChar); + DEFINE_LOCK_FREE_MACRO(SHORT, Short); + DEFINE_LOCK_FREE_MACRO(INT, Int); + DEFINE_LOCK_FREE_MACRO(LONG, Long); + DEFINE_LOCK_FREE_MACRO(LLONG, LongLong); + Builder.defineMacro("__GCC_ATOMIC_POINTER_LOCK_FREE", + getLockFreeValue(TI.getPointerWidth(0), + TI.getPointerAlign(0), + InlineWidthBits)); +#undef DEFINE_LOCK_FREE_MACRO + if (LangOpts.NoInlineDefine) Builder.defineMacro("__NO_INLINE__"); |
