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This is identical on all architectures except ARM32. Add one extra SELF_TEST to check that hweight64() works when the input is split in half. No functional change. Signed-off-by: Andrew Cooper Reviewed-by: Jan Beulich Acked-by: Stefano Stabellini --- CC: Jan Beulich CC: Roger Pau Monné CC: Stefano Stabellini CC: Julien Grall CC: Volodymyr Babchuk CC: Bertrand Marquis CC: Michal Orzel CC: Oleksii Kurochko CC: Shawn Anastasio v3: * Use >=, even if it does differ from ffs() v2: * Reorder with respect to the hweight32() patch * s/__pure/attr_const/ --- xen/arch/arm/include/asm/bitops.h | 8 ------ xen/arch/ppc/include/asm/bitops.h | 8 ------ xen/arch/x86/include/asm/bitops.h | 8 ------ xen/common/bitops.c | 3 +++ xen/include/xen/bitops.h | 45 ++++++------------------------- 5 files changed, 11 insertions(+), 61 deletions(-) diff --git a/xen/arch/arm/include/asm/bitops.h b/xen/arch/arm/include/asm/bitops.h index b28c25b3d52d..f163d9bb4578 100644 --- a/xen/arch/arm/include/asm/bitops.h +++ b/xen/arch/arm/include/asm/bitops.h @@ -78,14 +78,6 @@ bool clear_mask16_timeout(uint16_t mask, volatile void *p, #define arch_fls(x) ((x) ? 32 - __builtin_clz(x) : 0) #define arch_flsl(x) ((x) ? BITS_PER_LONG - __builtin_clzl(x) : 0) -/** - * hweightN - returns the hamming weight of a N-bit word - * @x: the word to weigh - * - * The Hamming Weight of a number is the total number of bits set in it. - */ -#define hweight64(x) generic_hweight64(x) - #endif /* _ARM_BITOPS_H */ /* * Local variables: diff --git a/xen/arch/ppc/include/asm/bitops.h b/xen/arch/ppc/include/asm/bitops.h index f488a7c03425..c942e9432e20 100644 --- a/xen/arch/ppc/include/asm/bitops.h +++ b/xen/arch/ppc/include/asm/bitops.h @@ -126,12 +126,4 @@ static inline int test_and_set_bit(unsigned int nr, volatile void *addr) #define arch_hweightl(x) __builtin_popcountl(x) -/** - * hweightN - returns the hamming weight of a N-bit word - * @x: the word to weigh - * - * The Hamming Weight of a number is the total number of bits set in it. - */ -#define hweight64(x) __builtin_popcountll(x) - #endif /* _ASM_PPC_BITOPS_H */ diff --git a/xen/arch/x86/include/asm/bitops.h b/xen/arch/x86/include/asm/bitops.h index 507b043b8a86..642d8e58b288 100644 --- a/xen/arch/x86/include/asm/bitops.h +++ b/xen/arch/x86/include/asm/bitops.h @@ -475,12 +475,4 @@ static always_inline unsigned int arch_flsl(unsigned long x) } #define arch_flsl arch_flsl -/** - * hweightN - returns the hamming weight of a N-bit word - * @x: the word to weigh - * - * The Hamming Weight of a number is the total number of bits set in it. - */ -#define hweight64(x) generic_hweight64(x) - #endif /* _X86_BITOPS_H */ diff --git a/xen/common/bitops.c b/xen/common/bitops.c index 5e5d20d225d7..91ae961440af 100644 --- a/xen/common/bitops.c +++ b/xen/common/bitops.c @@ -144,6 +144,9 @@ static void __init test_hweight(void) CHECK(hweightl, 1 | (1UL << (BITS_PER_LONG - 1)), 2); CHECK(hweightl, -1UL, BITS_PER_LONG); + + /* unsigned int hweight64(uint64_t) */ + CHECK(hweight64, -1ULL, 64); } static void __init __constructor test_bitops(void) diff --git a/xen/include/xen/bitops.h b/xen/include/xen/bitops.h index a462c3065158..12eb88fb1255 100644 --- a/xen/include/xen/bitops.h +++ b/xen/include/xen/bitops.h @@ -331,6 +331,14 @@ static always_inline attr_const unsigned int hweight32(uint32_t x) return hweightl(x); } +static always_inline attr_const unsigned int hweight64(uint64_t x) +{ + if ( BITS_PER_LONG >= 64 ) + return hweightl(x); + else + return hweight32(x >> 32) + hweight32(x); +} + /* --------------------- Please tidy below here --------------------- */ #ifndef find_next_bit @@ -399,43 +407,6 @@ static inline int get_count_order(unsigned int count) return order; } -/* - * hweightN: returns the hamming weight (i.e. the number - * of bits set) of a N-bit word - */ - -static inline unsigned int generic_hweight32(unsigned int w) -{ - w -= (w >> 1) & 0x55555555; - w = (w & 0x33333333) + ((w >> 2) & 0x33333333); - w = (w + (w >> 4)) & 0x0f0f0f0f; - - if ( IS_ENABLED(CONFIG_HAS_FAST_MULTIPLY) ) - return (w * 0x01010101) >> 24; - - w += w >> 8; - - return (w + (w >> 16)) & 0xff; -} - -static inline unsigned int generic_hweight64(uint64_t w) -{ - if ( BITS_PER_LONG < 64 ) - return generic_hweight32(w >> 32) + generic_hweight32(w); - - w -= (w >> 1) & 0x5555555555555555UL; - w = (w & 0x3333333333333333UL) + ((w >> 2) & 0x3333333333333333UL); - w = (w + (w >> 4)) & 0x0f0f0f0f0f0f0f0fUL; - - if ( IS_ENABLED(CONFIG_HAS_FAST_MULTIPLY) ) - return (w * 0x0101010101010101UL) >> 56; - - w += w >> 8; - w += w >> 16; - - return (w + (w >> 32)) & 0xFF; -} - /* * rol32 - rotate a 32-bit value left *