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Own branch of Oasis Linux (upstream: <https://git.sr.ht/~mcf/oasis/>) git clone https://anongit.hacktivis.me/git/oasis.git

0001-Add-portable-fallback-for-ctz-clz-and-clzll.patch (1732B)

    

  1. From 881ceef5adda6f1cc5f5a9a15ae74b068bf85dd4 Mon Sep 17 00:00:00 2001
  2. From: Michael Forney <mforney@mforney.org>
  3. Date: Fri, 30 Apr 2021 18:45:18 -0700
  4. Subject: [PATCH] Add portable fallback for ctz, clz, and clzll
  6. ---
  7.  include/common/attributes.h | 27 +++++++++++++++++++++++++--
  8.  1 file changed, 25 insertions(+), 2 deletions(-)
  10. diff --git a/include/common/attributes.h b/include/common/attributes.h
  11. index 4ccc421..72d5202 100644
  12. --- a/include/common/attributes.h
  13. +++ b/include/common/attributes.h
  14. @@ -32,6 +32,7 @@
  15.  
  16.  #include <stddef.h>
  17.  #include <assert.h>
  18. +#include <strings.h>
  19.  
  20.  #ifndef __has_attribute
  21.  #define __has_attribute(x) 0
  22. @@ -156,7 +157,7 @@ static inline int clzll(const unsigned long long mask) {
  23.          return clz((unsigned)mask) + 32;
  24.  }
  25.  #endif /* _WIN64 */
  26. -#else /* !_MSC_VER */
  27. +#elif defined(__GNUC__)
  28.  static inline int ctz(const unsigned int mask) {
  29.      return __builtin_ctz(mask);
  30.  }
  31. @@ -168,7 +169,29 @@ static inline int clz(const unsigned int mask) {
  32.  static inline int clzll(const unsigned long long mask) {
  33.      return __builtin_clzll(mask);
  34.  }
  35. -#endif /* !_MSC_VER */
  36. +#else /* __GNUC__ */
  37. +static inline int ctz(const unsigned int mask) {
  38. +    return ffs(mask) - 1;
  39. +}
  40. +
  41. +static inline int clz(unsigned int mask) {
  42. +    mask >>= 1;
  43. +    mask |= mask >> 1;
  44. +    mask |= mask >> 2;
  45. +    mask |= mask >> 4;
  46. +    mask |= mask >> 8;
  47. +    mask |= mask >> 16;
  48. +    mask++;
  49. +    return 32 - ffs(mask);
  50. +}
  51. +
  52. +static inline int clzll(unsigned long long mask) {
  53. +    if (mask >> 32)
  54. +        return clz((unsigned)(mask >> 32));
  55. +    else
  56. +        return clz((unsigned)mask) + 32;
  57. +}
  58. +#endif /* !_MSC_VER && !__GNUC__ */
  59.  
  60.  #ifndef static_assert
  61.  #define CHECK_OFFSET(type, field, name) \
  62. -- 
  63. 2.32.0