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>
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