Storing defers this way has the benefits that the defer doesn't get
analyzed multiple times in AstGen, it takes up less space, and it
makes Sema aware of defers allowing for 'unreachable else prong'
error on error sets in generic code.
The disadvantage is that it is a bit more complex and errdefers with
payloads now emit a placeholder instruction (but those are rare).
Sema.zig before:
Total ZIR bytes: 3.7794370651245117MiB
Instructions: 238996 (2.051319122314453MiB)
String Table Bytes: 89.2802734375KiB
Extra Data Items: 430144 (1.640869140625MiB)
Sema.zig after:
Total ZIR bytes: 3.3344192504882812MiB
Instructions: 211829 (1.8181428909301758MiB)
String Table Bytes: 89.2802734375KiB
Extra Data Items: 374611 (1.4290275573730469MiB)
Companion commit to 61a53a587558ff1fe1b0ec98bb424022885edccf.
This commit also moves over a bunch of behavior test cases to the
passing-for-stage2 section.
Conflicts:
* doc/langref.html.in
* lib/std/enums.zig
* lib/std/fmt.zig
* lib/std/hash/auto_hash.zig
* lib/std/math.zig
* lib/std/mem.zig
* lib/std/meta.zig
* test/behavior/alignof.zig
* test/behavior/bitcast.zig
* test/behavior/bugs/1421.zig
* test/behavior/cast.zig
* test/behavior/ptrcast.zig
* test/behavior/type_info.zig
* test/behavior/vector.zig
Master branch added `try` to a bunch of testing function calls, and some
lines also had changed how to refer to the native architecture and other
`@import("builtin")` stuff.
