Changeset 26a9388 in mainline for kernel/generic/include

Timestamp:

2026-01-29T15:20:01Z (4 days ago)

Author:

Martin Decky <martin@…>

Branches:

master

Children:

d1a551f, d98f43e

Parents:

c35cc8b

Message:

Use the stack pointer to derive CURRENT (if possible)

If provided by the compiler, use the builtin_stack_address()
intrinsic instead of builtin_frame_address(0) to derive CURRENT.

This generally generates faster and shorter code. In cases where the
compiler does not maintain the frame pointer rountinely, it also does
not force the compiler to establish the stack frame for the current
function.

File:

• kernel/generic/include/arch.h (modified) (1 diff)

kernel/generic/include/arch.h

@@ -49 +49 @@
  *
  */
+#if __has_builtin(__builtin_stack_address)
+
+#define CURRENT \
+        ((current_t *) (((uintptr_t) __builtin_stack_address()) & \
+            (~((uintptr_t) STACK_SIZE - 1))))
+
+#else
+
 #define CURRENT \
         ((current_t *) (((uintptr_t) __builtin_frame_address(0)) & \
             (~((uintptr_t) STACK_SIZE - 1))))
+
+#endif
 
 #define MAGIC  UINT32_C(0xfacefeed)