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Chris Tate
0b483e8650
- Index walks (slice, substring, substr, startsWith/endsWith with a position, lastIndexOf results) on a non-ASCII receiver of 64 KiB or more: once they would have paid for one pass over it, the receiver's index entry keeps every unit's byte offset (a 32-bit base per 64 units and one byte per unit), and indexes map with two loads. Before that, a walk within 64 units of the hot cursor starts from it, without the index search. The index entry stays 128 bytes on 64-bit targets. - lastIndexOf on non-ASCII receivers tests the needle's first byte before comparing, as the ASCII path does. - normalize: a quick check (UAX #15) returns the receiver when every code point is inert for the form: unchanged when normalized alone, combining class 0, and, in the ranges checked, never the second element of a composition. Other text normalizes segment by segment, each starting at a starter, so runs of inert code points copy as they are and a lone precomposed letter's result is kept per form. The per-code-point facts come from unicode_normalize, 256 code points at a time.