commit | 1e24fe7d699a1c36be142afa21859c6a9c82d035 | [log] [tgz] |
---|---|---|
author | Ryan Macnak <rmacnak@google.com> | Wed Jun 12 21:56:53 2019 +0000 |
committer | commit-bot@chromium.org <commit-bot@chromium.org> | Wed Jun 12 21:56:53 2019 +0000 |
tree | 26805de8a52d8a63aaa5c2161640e5b6e8e6a910 | |
parent | f005bd5a3eded7dffe90e6fb2e7ea12db631fe21 [diff] |
[vm, compiler] Specialize unoptimized monomorphic and megamorphic calls. dart-bytecode, arm64: +4.742% geomean dart-bytecode-jit-unopt, arm64: +12.73% geomean dart2js-compile, x64: +3.635% geomean In the polymorphic and unlinked cases, call to a stub the does a linear scan against an ICData. In the monomorphic case, call to a prologue of the expected target function that checks the expected receiver class. There is additional indirection in the JIT version compared to the AOT version to also tick a usage counter so the inliner can make good decisions. In the megamorphic case, call to a stub that does a hash table lookup against a MegamorphicCache. Megamorphic call sites face a loss of precision in usage counts. The call site count is not recorded and the usage counter of the target function is used as an approximation. Monomorphic and megamorphic calls sites are reset to the polymorphic/unlinked state on hot reload. Monomorphic and megamorphic calls sites do not check the stepping state, so they are reset to the polymorphic/unlinked state when stepping begins and disabled. Back-edges now increment the usage counter in addition to checking it. This ensures function with loops containing monomorphic calls will eventually cross the optimization threshold. Fixed backwards use of kMonomorphicEntryOffset and kPolymorphicEntryOffset. Fixed C stack overflow when bouncing between the KBC interpreter and a simulator. Bug: https://github.com/dart-lang/sdk/issues/26780 Bug: https://github.com/dart-lang/sdk/issues/36409 Bug: https://github.com/dart-lang/sdk/issues/36731 Change-Id: I78a49cccd962703a459288e71ce246ed845df474 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/102820 Commit-Queue: Ryan Macnak <rmacnak@google.com> Reviewed-by: Alexander Markov <alexmarkov@google.com>
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