From 7ded1afe0a518c65c5f2850984419287ac880fa1 Mon Sep 17 00:00:00 2001 From: Tim Wawrzynczak Date: Thu, 1 Oct 2020 15:36:42 -0600 Subject: [PATCH] lib and libpayload: add 64-bit versions of clz, __ffs and log2 Add 64-bit versions of clz, __ffs & log2: `__ffs64`, `__clz64`, and `log2_64`. Signed-off-by: Tim Wawrzynczak Change-Id: Iefc6e6c51f5b20607c88e38660a499a4f77ce0d0 Reviewed-on: https://review.coreboot.org/c/coreboot/+/45938 Tested-by: build bot (Jenkins) Reviewed-by: Julius Werner Reviewed-by: Angel Pons --- payloads/libpayload/include/libpayload.h | 8 ++++++++ src/include/lib.h | 4 ++++ 2 files changed, 12 insertions(+) diff --git a/payloads/libpayload/include/libpayload.h b/payloads/libpayload/include/libpayload.h index 01d71b8e61..475fe0f3fc 100644 --- a/payloads/libpayload/include/libpayload.h +++ b/payloads/libpayload/include/libpayload.h @@ -454,6 +454,14 @@ static inline int clz(u32 x) static inline int log2(u32 x) { return (int)sizeof(x) * 8 - clz(x) - 1; } /* Find First Set: __ffs(0xf) == 0, __ffs(0) == -1, __ffs(1 << 31) == 31 */ static inline int __ffs(u32 x) { return log2(x & (u32)(-(s32)x)); } + +static inline int clz64(u64 x) +{ + return x ? __builtin_clzll(x) : sizeof(x) * 8; +} + +static inline int log2_64(u64 x) { return sizeof(x) * 8 - clz64(x) - 1; } +static inline int __ffs64(u64 x) { return log2_64(x & (u64)(-(s64)x)); } /** @} */ /** diff --git a/src/include/lib.h b/src/include/lib.h index 46d8b02112..a0003d3e29 100644 --- a/src/include/lib.h +++ b/src/include/lib.h @@ -56,4 +56,8 @@ static inline int __ffs(u32 x) { return log2(x & (u32)(-(s32)x)); } /* Integer binary logarithm (rounding up): log2_ceil(0) == -1, log2(5) == 3 */ static inline int log2_ceil(u32 x) { return (x == 0) ? -1 : log2(x * 2 - 1); } +static inline int clz64(u64 x) { return x ? __builtin_clzll(x) : sizeof(x) * 8; } +static inline int log2_64(u64 x) { return sizeof(x) * 8 - clz64(x) - 1; } +static inline int __ffs64(u64 x) { return log2_64(x & (u64)(-(s64)x)); } + #endif /* __LIB_H__ */