Reland "[dart2wasm] Use single unsigned cmp instead of two cmps when possible"

This is a reland of commit 8b1aa1860f1c9ca0e59530576680a0b13b3f3400

This relands the commit with the following changes to avoid regressions
and some random changes:

- Add inline annotations to `IntToWasmInt` extensions.

  These methods are 3 instructions long and often become just one
  instruction when inlined, but wasm-opt still doesn't inline them,
  turning a single `i64.lt_u` and similar into a function call.

- Revert changes from `length.leU(index)` to `index.geU(length)`.

  I had done this change because I find `if (index >= length) throw`
  easier to read than `if (length <= index) throw`, but the change
  introduced some larger changes in the wasm-opt output. These changes
  are probably harmless, but to minimize unintentional changes I
  reverted these changes for now.

Original change's description:
> [dart2wasm] Use single unsigned cmp instead of two cmps when possible
>
> wasm-opt doesn't optimize `0 < x || x > y` when y is known to be
> positive (e.g. a positive integer constant), so we do it manually.
>
> We also do it in a few places where `y` is not known to be positive in
> the Wasm code, but we know it's always positive, for example when it's a
> length.
>
> Example improvement in the wasm-opt output:
>
> ```
>    (func $_newArrayLengthCheck (;426;) (param $var0 i64) (result i64)
>      local.get $var0
>      i64.const 2147483647
> -    i64.le_s
> -    local.get $var0
> -    i64.const 0
> -    i64.ge_s
> -    i32.and
> -    i32.eqz
> +    i64.gt_u
>      if
>        i32.const 46
>        i32.const 0
> @@ -19190,13 +19172,8 @@
>                i64.const 97
>                i64.sub
>                local.tee $var3
> -              i64.const 0
> -              i64.ge_s
> -              local.get $var3
>                i64.const 5
> -              i64.le_s
> -              i32.and
> -              i32.eqz
> +              i64.gt_u
>                if
>                  local.get $var0
>                  local.get $var6
> @@ -19810,10 +19787,10 @@
>      global.get $global4
>      array.new_fixed $Array<_Type> 2
>    )
> ```
>
> Closes #56083.
>
> Change-Id: Idb1dd0d0809b26be8aec3d082aa341c59e1a353d
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/373663
> Reviewed-by: Martin Kustermann <kustermann@google.com>
> Commit-Queue: Ömer Ağacan <omersa@google.com>

Change-Id: I822ca612e5c8d5d33ba443107b72e9f1021c5c4a
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/374000
Reviewed-by: Martin Kustermann <kustermann@google.com>
Commit-Queue: Ömer Ağacan <omersa@google.com>
12 files changed
tree: 5ffeffdd991a84beadd8076b22f1cc817fe46b31
  1. .dart_tool/
  2. .github/
  3. benchmarks/
  4. build/
  5. docs/
  6. pkg/
  7. runtime/
  8. samples/
  9. sdk/
  10. tests/
  11. third_party/
  12. tools/
  13. utils/
  14. .clang-format
  15. .gitattributes
  16. .gitconfig
  17. .gitignore
  18. .gn
  19. .mailmap
  20. .style.yapf
  21. AUTHORS
  22. BUILD.gn
  23. CHANGELOG.md
  24. codereview.settings
  25. CONTRIBUTING.md
  26. DEPS
  27. LICENSE
  28. OWNERS
  29. PATENT_GRANT
  30. PRESUBMIT.py
  31. README.dart-sdk
  32. README.md
  33. sdk.code-workspace
  34. sdk_args.gni
  35. sdk_packages.yaml
  36. SECURITY.md
  37. WATCHLISTS
README.md

Dart

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