From 9c313ccdfc079f71f16c9b3d3a6c6d60996b9367 Mon Sep 17 00:00:00 2001 From: Thorsten Blum Date: Sun, 21 Apr 2024 00:38:37 +0200 Subject: bitops: Change function return types from long to int Change the return types of bitops functions (ffs, fls, and fns) from long to int. The expected return values are in the range [0, 64], for which int is sufficient. Additionally, int aligns well with the return types of the corresponding __builtin_* functions, potentially reducing overall type conversions. Many of the existing bitops functions already return an int and don't need to be changed. The bitops functions in arch/ should be considered separately. Adjust some return variables to match the function return types. With GCC 13 and defconfig, these changes reduced the size of a test kernel image by 5,432 bytes on arm64 and by 248 bytes on riscv; there were no changes in size on x86_64, powerpc, or m68k. Signed-off-by: Thorsten Blum Signed-off-by: Arnd Bergmann --- tools/include/asm-generic/bitops/__ffs.h | 4 ++-- tools/include/asm-generic/bitops/__fls.h | 4 ++-- tools/include/linux/bitops.h | 2 +- 3 files changed, 5 insertions(+), 5 deletions(-) (limited to 'tools') diff --git a/tools/include/asm-generic/bitops/__ffs.h b/tools/include/asm-generic/bitops/__ffs.h index 9d1310519497..2d94c1e9b2f3 100644 --- a/tools/include/asm-generic/bitops/__ffs.h +++ b/tools/include/asm-generic/bitops/__ffs.h @@ -11,9 +11,9 @@ * * Undefined if no bit exists, so code should check against 0 first. */ -static __always_inline unsigned long __ffs(unsigned long word) +static __always_inline unsigned int __ffs(unsigned long word) { - int num = 0; + unsigned int num = 0; #if __BITS_PER_LONG == 64 if ((word & 0xffffffff) == 0) { diff --git a/tools/include/asm-generic/bitops/__fls.h b/tools/include/asm-generic/bitops/__fls.h index 54ccccf96e21..e974ec932ec1 100644 --- a/tools/include/asm-generic/bitops/__fls.h +++ b/tools/include/asm-generic/bitops/__fls.h @@ -10,9 +10,9 @@ * * Undefined if no set bit exists, so code should check against 0 first. */ -static __always_inline unsigned long generic___fls(unsigned long word) +static __always_inline unsigned int generic___fls(unsigned long word) { - int num = BITS_PER_LONG - 1; + unsigned int num = BITS_PER_LONG - 1; #if BITS_PER_LONG == 64 if (!(word & (~0ul << 32))) { diff --git a/tools/include/linux/bitops.h b/tools/include/linux/bitops.h index 7319f6ced108..8e073a111d2a 100644 --- a/tools/include/linux/bitops.h +++ b/tools/include/linux/bitops.h @@ -70,7 +70,7 @@ static inline unsigned long hweight_long(unsigned long w) return sizeof(w) == 4 ? hweight32(w) : hweight64(w); } -static inline unsigned fls_long(unsigned long l) +static inline unsigned int fls_long(unsigned long l) { if (sizeof(l) == 4) return fls(l); -- cgit v1.2.3