tree 7dd5eed79b4a0bc7b1b2aff81148bac545ffe323
parent c5cc9aeb6a566366488e0cb6e02a634d97cb786d
author Tess Strickland <sstrickl@google.com> 1705407221 +0000
committer Commit Queue <dart-scoped@luci-project-accounts.iam.gserviceaccount.com> 1705407221 +0000

[vm/compiler] Fix ARM7 regression after 1827fcbf68bf.

The refactoring in https://dart-review.googlesource.com/c/sdk/+/345002
erroneously assumed that if the caller to
Assembler::AddressCanHoldConstantIndex didn't pass an out parameter to
detect whether a base register was needed, that that case shouldn't be
considered.

While it's true that LoadIndexedInstr::MakeLocationSummary originally
ignored the value stored in the out parameter, it did that because it
can use TMP to store the array base, unlike the code for
StoreIndexedInstr which must have a temporary register allocated during
register allocation.

Thus, fix Assembler::AddressCanHoldConstantIndex to always require
the out parameter, and add a comment in LoadIndexedInstr as to why
we ignore the out parameter in this case instead of allocating an
additional temporary register.

TEST=vm/cc/Assembler_Regress54621

Fixes: https://github.com/dart-lang/sdk/issues/54621
Change-Id: I0af557565faf657a87641457884334446e9b7cc5
Cq-Include-Trybots: luci.dart.try:vm-ffi-qemu-linux-release-arm-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/346201
Reviewed-by: Martin Kustermann <kustermann@google.com>
Commit-Queue: Tess Strickland <sstrickl@google.com>