objtool, x86/hweight: Remove ANNOTATE_IGNORE_ALTERNATIVE

JIRA: https://issues.redhat.com/browse/RHEL-94124

commit 7b3169d
Author: Josh Poimboeuf <jpoimboe@kernel.org>
Date:   Thu Apr 10 13:58:35 2025 -0700

    objtool, x86/hweight: Remove ANNOTATE_IGNORE_ALTERNATIVE

    Since objtool's inception, frame pointer warnings have been manually
    silenced for __arch_hweight*() to allow those functions' inline asm to
    avoid using ASM_CALL_CONSTRAINT.

    The potentially dubious reasoning for that decision over nine years ago
    was that since !X86_FEATURE_POPCNT is exceedingly rare, it's not worth
    hurting the code layout for a function call that will never happen on
    the vast majority of systems.

    However, those functions actually started using ASM_CALL_CONSTRAINT with
    the following commit:

      194a613 ("x86/hweight: Use ASM_CALL_CONSTRAINT in inline asm()")

    And rightfully so, as it makes the code correct.  ASM_CALL_CONSTRAINT
    will soon have no effect for non-FP configs anyway.

    With ASM_CALL_CONSTRAINT in place, ANNOTATE_IGNORE_ALTERNATIVE no longer
    has a purpose for the hweight functions.  Remove it.

    Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
    Signed-off-by: Ingo Molnar <mingo@kernel.org>
    Cc: Andy Lutomirski <luto@kernel.org>
    Cc: Brian Gerst <brgerst@gmail.com>
    Cc: H. Peter Anvin <hpa@zytor.com>
    Cc: Juergen Gross <jgross@suse.com>
    Cc: Kees Cook <keescook@chromium.org>
    Cc: Linus Torvalds <torvalds@linux-foundation.org>
    Link: https://lore.kernel.org/r/e7070dba3278c90f1a836b16157dcd34ccd21e21.1744318586.git.jpoimboe@kernel.org

Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>

Author: joe-lawrence

arch/x86/include/asm/arch_hweight.h

@@ -16,8 +16,7 @@ static __always_inline unsigned int __arch_hweight32(unsigned int w)
 {
 	unsigned int res;
 
-	asm_inline (ALTERNATIVE(ANNOTATE_IGNORE_ALTERNATIVE
-				"call __sw_hweight32",
+	asm_inline (ALTERNATIVE("call __sw_hweight32",
 				"popcntl %[val], %[cnt]", X86_FEATURE_POPCNT)
 			 : [cnt] "=" REG_OUT (res), ASM_CALL_CONSTRAINT
 			 : [val] REG_IN (w));
@@ -46,8 +45,7 @@ static __always_inline unsigned long __arch_hweight64(__u64 w)
 {
 	unsigned long res;
 
-	asm_inline (ALTERNATIVE(ANNOTATE_IGNORE_ALTERNATIVE
-				"call __sw_hweight64",
+	asm_inline (ALTERNATIVE("call __sw_hweight64",
 				"popcntq %[val], %[cnt]", X86_FEATURE_POPCNT)
 			 : [cnt] "=" REG_OUT (res), ASM_CALL_CONSTRAINT
 			 : [val] REG_IN (w));