This revision was automatically updated to reflect the committed changes.
Closed by commit rGdc155744c82f: [Frontend] Correct values of
ATOMIC_*_LOCK_FREE to match builtin (authored by mgorny).
Herald added a subscriber: dexonsmith.
Herald added a project: clang.
Changed prior to commit:
https://reviews.llvm.org/D28213?vs=83677&id=223551#toc
Repository:
rG LLVM Github Monorepo
CHANGES SINCE LAST ACTION
https://reviews.llvm.org/D28213/new/
https://reviews.llvm.org/D28213
Files:
clang/lib/Frontend/InitPreprocessor.cpp
clang/test/Sema/atomic-ops.c
Index: clang/test/Sema/atomic-ops.c
===================================================================
--- clang/test/Sema/atomic-ops.c
+++ clang/test/Sema/atomic-ops.c
@@ -14,11 +14,7 @@
_Static_assert(__GCC_ATOMIC_SHORT_LOCK_FREE == 2, "");
_Static_assert(__GCC_ATOMIC_INT_LOCK_FREE == 2, "");
_Static_assert(__GCC_ATOMIC_LONG_LOCK_FREE == 2, "");
-#ifdef __i386__
-_Static_assert(__GCC_ATOMIC_LLONG_LOCK_FREE == 1, "");
-#else
_Static_assert(__GCC_ATOMIC_LLONG_LOCK_FREE == 2, "");
-#endif
_Static_assert(__GCC_ATOMIC_POINTER_LOCK_FREE == 2, "");
_Static_assert(__c11_atomic_is_lock_free(1), "");
Index: clang/lib/Frontend/InitPreprocessor.cpp
===================================================================
--- clang/lib/Frontend/InitPreprocessor.cpp
+++ clang/lib/Frontend/InitPreprocessor.cpp
@@ -286,12 +286,12 @@
/// 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) {
+static const char *getLockFreeValue(unsigned TypeWidth, 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)
+ // Note: we do not need to check alignment since _Atomic(T) is always
+ // appropriately-aligned in clang.
+ if ((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.
@@ -881,7 +881,6 @@
#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);
@@ -894,7 +893,6 @@
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
}
Index: clang/test/Sema/atomic-ops.c
===================================================================
--- clang/test/Sema/atomic-ops.c
+++ clang/test/Sema/atomic-ops.c
@@ -14,11 +14,7 @@
_Static_assert(__GCC_ATOMIC_SHORT_LOCK_FREE == 2, "");
_Static_assert(__GCC_ATOMIC_INT_LOCK_FREE == 2, "");
_Static_assert(__GCC_ATOMIC_LONG_LOCK_FREE == 2, "");
-#ifdef __i386__
-_Static_assert(__GCC_ATOMIC_LLONG_LOCK_FREE == 1, "");
-#else
_Static_assert(__GCC_ATOMIC_LLONG_LOCK_FREE == 2, "");
-#endif
_Static_assert(__GCC_ATOMIC_POINTER_LOCK_FREE == 2, "");
_Static_assert(__c11_atomic_is_lock_free(1), "");
Index: clang/lib/Frontend/InitPreprocessor.cpp
===================================================================
--- clang/lib/Frontend/InitPreprocessor.cpp
+++ clang/lib/Frontend/InitPreprocessor.cpp
@@ -286,12 +286,12 @@
/// 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) {
+static const char *getLockFreeValue(unsigned TypeWidth, 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)
+ // Note: we do not need to check alignment since _Atomic(T) is always
+ // appropriately-aligned in clang.
+ if ((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.
@@ -881,7 +881,6 @@
#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);
@@ -894,7 +893,6 @@
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
}
_______________________________________________
cfe-commits mailing list
cfe-commits@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
