LoadOptimizer has a builtin alias-analysis which recognized only
Redefinition and AssertAssignable as instructions which must
be followed through when traversing use lists for a given
definition. However after recent changes CheckNull should be
treated the same way as these other two instructions.
This lead to incorrect computation of aliasing identity and
consequently incorrect load forwarding.
This change fixes this bug and also changes implementation of
OriginalDefinition in a way that makes aliasing analysis code
more future-proof.
We introduce virtual method Definition::RedefinedValue and
reimplement Definition::OriginalDefinition through RedefinedValue.
Aliasing analysis is changed to use RedefinedValue to detect
if an instruction is a redefinition.
Fixes https://github.com/flutter/flutter/issues/30619
Bug: https://github.com/flutter/flutter/issues/30619
Change-Id: I8019c93779491a4e6f127119d1d56eb037a3bb56
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/99170
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
Auto-Submit: Vyacheslav Egorov <vegorov@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
In general we would like to keep previous results of type propagation passes, however this
leads to situations where CompileType objects owned by definitions are cached as reaching
types at uses that are no longer directly connected to the definition itself.
This leads to situations when type propagator updates the type of the definition in place
via Definition::UpdateType, but does not enqueue an instruction which uses this type which
leads to incorrect fix-point computation.
As a fix we make the fact that some CompileType objects are owned by definitions explicit
by assigning [CompileType::owner_] field. Whenever we encounter situation that reaching type's
owner does not match current definition flowing into use we clone compile type to disconnect
it from original owner and prevent hidden mutation.
This CL also fixes two minor issues:
- incorrect computation of non-nullable type from a nullable CompileType with a cid;
- assings CompileType to LoadIndexedUnsafe instructions emitted by prologue builder;
Fixes https://github.com/dart-lang/sdk/issues/36156
Bug: 36156
Change-Id: I6536cfe1fda033cba3524336bfbdb871b88a8b3f
Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-android-release-arm-try, vm-kernel-precomp-bare-linux-release-simarm-try, vm-kernel-precomp-bare-linux-release-simarm64-try, vm-kernel-precomp-bare-linux-release-x64-try, vm-kernel-precomp-linux-debug-x64-try, vm-kernel-precomp-linux-product-x64-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/98358
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
This helper class can be used for building IL in SSA form. It was
previously used to build intrinsic IL, but it can also be used to
build IL for tests.
This move required introducing a constant that describes offset
of the last parameter from SP value on entry (kLastParamFrom
This CL also changes the meaning of ParameterInstr(index, SPREG) to be
[SP + index + kLastParamSlotFromEntrySp], where previously it was
something like [SP + (index - 1) + kLastParamSlotFromEntrySp].
Change-Id: Ib75ecb3a94f9cde74d6f91028d3cbea8f5e4bc42
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/98336
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Liam Appelbe