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Simplify unaligned write for pre-computed string hash

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Alan Wu 2024-06-13 17:59:40 -04:00
parent a8730adb60
commit 6416ee33eb
1 changed files with 2 additions and 3 deletions
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5
string.c
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@ -376,9 +376,8 @@ str_precompute_hash(VALUE str)
RUBY_ASSERT(free_bytes >= sizeof(st_index_t)); RUBY_ASSERT(free_bytes >= sizeof(st_index_t));
#endif #endif
typedef struct {char bytes[sizeof(st_index_t)];} unaligned_index; st_index_t hash = str_do_hash(str);
union {st_index_t i; unaligned_index b;} u = {.i = str_do_hash(str)}; memcpy(RSTRING_END(str) + TERM_LEN(str), &hash, sizeof(hash));
*(unaligned_index *)(RSTRING_END(str) + TERM_LEN(str)) = u.b;
FL_SET(str, STR_PRECOMPUTED_HASH); FL_SET(str, STR_PRECOMPUTED_HASH);