tree ac5d5b01b890ebbf263d45675c2e8a98970ba601
parent 93455a0a43f16bc7f7ece7ba196c411f01c28b2f
author Lokesh Gidra <lokeshgidra@google.com> 1662482135 -0700
committer Lokesh Gidra <lokeshgidra@google.com> 1663255178 +0000

Reserve marking register for all GCs

Nterp relies on marking register to know if GC is happening. This is why
from the beginning nterp was enabled only if kUseReadBarrier was true.
Now, with userfaultfd GC merged in, this requirement hasn't changed. But
since userfaultfd GC is able to run even when marking register is
reserved, we allow nterp to be used with it. However, if at build time
read-barrier was disabled (using ART_USE_READ_BARRIER=false), then there
is no way to use nterp. This CL fixes this situation by reserving
marking register (and refreshing it) for every GC configuration.

This CL also puts back logic that was earlier taken away in the
userfaultfd GC to allow SS and CMS GCs to be used.

Test: ART_DEFAULT_GC_TYPE=SS ART_USE_READ_BARRIER=false art/test/testrunner/testrunner.py
--host --debug -bv
Test: Golem
Bug: 244737154

Change-Id: Ief336b9f39156571b7cd98d3d7f997eb82cd14c3