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d0586da18e
This commit expands on the foundations laid by https://github.com/ziglang/zig/pull/23177 and moves even more `Sema`-only functionality from `Value` to `Sema.arith`. Specifically all shift and bitwise operations, `@truncate`, `@bitReverse` and `@byteSwap` have been moved and adapted to the new rules around `undefined`. Especially the comptime shift operations have been basically rewritten, fixing many open issues in the process. New rules applied to operators: * `<<`, `@shlExact`, `@shlWithOverflow`, `>>`, `@shrExact`: compile error if any operand is undef * `<<|`, `~`, `^`, `@truncate`, `@bitReverse`, `@byteSwap`: return undef if any operand is undef * `&`, `|`: Return undef if both operands are undef, turn undef into actual `0xAA` bytes otherwise Additionally this commit canonicalizes the representation of aggregates with all-undefined members in the `InternPool` by disallowing them and enforcing the usage of a single typed `undef` value instead. This reduces the amount of edge cases and fixes a bunch of bugs related to partially undefined vecs. List of operations directly affected by this patch: * `<<`, `<<|`, `@shlExact`, `@shlWithOverflow` * `>>`, `@shrExact` * `&`, `|`, `~`, `^` and their atomic rmw + reduce pendants * `@truncate`, `@bitReverse`, `@byteSwap`