sdk/runtime/platform at 4fa2b017f004d53b774df2ea36a3dfbce5f244fc - sdk

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Samir Jindel d0909e068a Reland "[vm/aot] Only patch call-sites to monomorphic entry-points when the receiver is proven to be a heap object."

This reverts commit 5f81efb4a3.

Reason for revert: 3xH bot is green again.

Original change's description:
> Revert "[vm/aot] Only patch call-sites to monomorphic entry-points when the receiver is proven to be a heap object."
> 
> This reverts commit ab2026af45.
> 
> Reason for revert: Flutter 3xH is broken on Golem.
> 
> Original change's description:
> > [vm/aot] Only patch call-sites to monomorphic entry-points when the receiver is proven to be a heap object.
> > 
> > Flutter Gallery ARMv8: -0.8% total, -1.3% instructions
> > Flutter Gallery ARMv7: -0.7% total, -1.2% instructions
> > 
> > There are some performance regressions, in four categories:
> > 
> > 1. Arithmetic on num types (e.g. MinLib, MaxLib):
> >    We believe arithmetic on num types is rare in practice, and can be optimized later
> >    by specializing the call-sites.
> > 
> > 2. Lack of types (e.g. MeshDecompression, ImagingGaussianBlur, Crypto*):
> >    These (and similar benchmarks) are written in a very untyped style, which is not
> >    representative of Dart 2 style. We've confirmed that the regressions disappear if
> >    the benchmarks are annotated with appropriate types.
> > 
> > 3. Megamorphic calls which are specialized in the benchmark (e.g. DeltaBlue):
> >    DeltaBlue uses string interpolation in one place, so the toString() method in the
> >    string interpolation helper is monomorphic for _Smis. However, in a realistic programs,
> >    string interpolation is used much more frequently and with different types, so it's very
> >    unlikely that this call would be monomorphic. When string interpolation is removed, there's
> >    a remaining 1.3% regression on DeltaBlue which is not yet accounted for.
> > 
> > 4. Noisy benchmarks
> >    The remaining regressions are on benchmarks which show frequent jitter historically.
> > 
> > There are also 1-4% improvements on many benchmarks (Golem's "noise" analysis is hiding
> > many of them, look at the graphs).
> > 
> > For the reasons above, we believe the regressions justified by the code size improvement.
> > 
> > Change-Id: Ic9b281d4383a6111de9d6f44347976ffa61a6ca6
> > Cq-Include-Trybots:luci.dart.try:vm-kernel-precomp-linux-debug-x64-try,vm-kernel-precomp-linux-release-simarm-try,vm-kernel-precomp-linux-release-simarm64-try,vm-kernel-precomp-bare-linux-release-simarm64-try
> > Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/128667
> > Commit-Queue: Samir Jindel <sjindel@google.com>
> > Reviewed-by: Ryan Macnak <rmacnak@google.com>
> > Reviewed-by: Martin Kustermann <kustermann@google.com>
> 
> TBR=kustermann@google.com,rmacnak@google.com,alexmarkov@google.com,sjindel@google.com
> 
> Change-Id: I411aae4b230f2a08146ad3bf3e7a10aa6592db0e
> No-Presubmit: true
> No-Tree-Checks: true
> No-Try: true
> Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-linux-debug-x64-try, vm-kernel-precomp-linux-release-simarm-try, vm-kernel-precomp-linux-release-simarm64-try, vm-kernel-precomp-bare-linux-release-simarm64-try
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/131660
> Reviewed-by: Samir Jindel <sjindel@google.com>
> Commit-Queue: Samir Jindel <sjindel@google.com>

TBR=kustermann@google.com,rmacnak@google.com,alexmarkov@google.com,sjindel@google.com

# Not skipping CQ checks because original CL landed > 1 day ago.

Change-Id: I36e4e9d598033fcc934c2cdf5b061aa11255d3b2
Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-linux-debug-x64-try, vm-kernel-precomp-linux-release-simarm-try, vm-kernel-precomp-linux-release-simarm64-try, vm-kernel-precomp-bare-linux-release-simarm64-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/131837
Reviewed-by: Samir Jindel <sjindel@google.com>
Commit-Queue: Samir Jindel <sjindel@google.com>