Merge tag 'bitmap-for-6.14' of https://github.com:/norov/linux

Pull bitmap updates from Yury Norov:
 "This includes const_true() series from Vincent Mailhol, another
  __always_inline rework from Nathan Chancellor for RISCV, and a couple
  of random fixes from Dr. David Alan Gilbert and I Hsin Cheng"

* tag 'bitmap-for-6.14' of https://github.com:/norov/linux:
  cpumask: Rephrase comments for cpumask_any*() APIs
  cpu: Remove unused init_cpu_online
  riscv: Always inline bitops
  linux/bits.h: simplify GENMASK_INPUT_CHECK()
  compiler.h: add const_true()

1 files changed, 22 insertions, 0 deletions

diff --git a/include/linux/compiler.h b/include/linux/compiler.h
index efd43df3a99a..b087de2f3e94 100644
--- a/include/linux/compiler.h
+++ b/include/linux/compiler.h
@@ -308,6 +308,28 @@ static inline void *offset_to_ptr(const int *off)
 #define statically_true(x) (__builtin_constant_p(x) && (x))
 
 /*
+ * Similar to statically_true() but produces a constant expression
+ *
+ * To be used in conjunction with macros, such as BUILD_BUG_ON_ZERO(),
+ * which require their input to be a constant expression and for which
+ * statically_true() would otherwise fail.
+ *
+ * This is a trade-off: const_true() requires all its operands to be
+ * compile time constants. Else, it would always returns false even on
+ * the most trivial cases like:
+ *
+ *   true || non_const_var
+ *
+ * On the opposite, statically_true() is able to fold more complex
+ * tautologies and will return true on expressions such as:
+ *
+ *   !(non_const_var * 8 % 4)
+ *
+ * For the general case, statically_true() is better.
+ */
+#define const_true(x) __builtin_choose_expr(__is_constexpr(x), x, false)
+
+/*
  * This is needed in functions which generate the stack canary, see
  * arch/x86/kernel/smpboot.c::start_secondary() for an example.
  */