This reverts commit af251ddfec.
Reason for revert: Crashes on Windows.
Original change's description:
> [vm] Prefer stack bounds from the system thread library for overflow checks.
>
> Before this change, we would assume all stacks have the size the VM specifies for threads it creates, but this won't be accurate for the initial thread or threads created by the embedder.
>
> Change-Id: I6605a88d6666a6f9d47fbe047d3fdd02aa22c80a
> Reviewed-on: https://dart-review.googlesource.com/10209
> Reviewed-by: Zach Anderson <zra@google.com>
TBR=rmacnak@google.com,zra@google.com
Change-Id: I96eaccdc8edf6e3d319827a63d168534bad0518e
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://dart-review.googlesource.com/13106
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Before this change, we would assume all stacks have the size the VM specifies for threads it creates, but this won't be accurate for the initial thread or threads created by the embedder.
Change-Id: I6605a88d6666a6f9d47fbe047d3fdd02aa22c80a
Reviewed-on: https://dart-review.googlesource.com/10209
Reviewed-by: Zach Anderson <zra@google.com>
This CL includes db26c89347 (patch set #1)
with fix (patch set #2):
* Include simulator.h explicitly where it is required as it is no
longer included implicitly through other header files.
Original review: https://codereview.chromium.org/2995803002/
When running on the simulator for arm/arm64, compare-and-swap operations
used in VM were synchronized with simulator using mutex.
It heavily impacts performance when doing parallel marking due to high
contention (see #30317).
This synchronization was implemented in order to make simulated
LDREX/STREX instructions aware of CAS performed in VM.
This CL drops this synchronization between VM and simulator:
CAS operations in VM become regular, and simulator remembers value loaded
with load-exclusive and performs CAS when doing store-exclusive to catch
any concurrent modifications.
Speeds up gen_snapshot of flutter benchmark complex_layout from 9.2s
to 8.0s on my MacBook.
R=asiva@google.com
Review-Url: https://codereview.chromium.org/2999853002 .
When running on the simulator for arm/arm64, compare-and-swap operations
used in VM were synchronized with simulator using mutex.
It heavily impacts performance when doing parallel marking due to high
contention (see #30317).
This synchronization was implemented in order to make simulated
LDREX/STREX instructions aware of CAS performed in VM.
This CL drops this synchronization between VM and simulator:
CAS operations in VM become regular, and simulator remembers value loaded
with load-exclusive and performs CAS when doing store-exclusive to catch
any concurrent modifications.
Speeds up gen_snapshot of flutter benchmark complex_layout from 9.2s
to 8.0s on my MacBook.
R=asiva@google.com, rmacnak@google.com
Review-Url: https://codereview.chromium.org/2995803002 .
Inline instance object hash code into object header on 64 bit.
64 bit objects have 32 bits of free space in the header word.
This is used for the hash code in string objects. We take it
for the default hash code on all objects that don't override
the hashCode getter.
This is both faster and a memory reduction. Eg it makes the
MegaHashCode part of the Megamorphic benchmark 6 times faster.
This is a reland of https://codereview.chromium.org/2954453002/
which fixes an issue that made script snapshots generated on
64 bit platforms incompatible with 32 bit VMs.
BUG=
R=vegorov@google.com
Review-Url: https://codereview.chromium.org/2965723002 .
Inline instance object hash code into object header on 64 bit.
64 bit objects have 32 bits of free space in the header word.
This is used for the hash code in string objects. We take it
for the default hash code on all objects that don't override
the hashCode getter.
This is both faster and a memory reduction. Eg it makes the
MegaHashCode part of the Megamorphic benchmark 6 times faster.
This is a reland of https://codereview.chromium.org/2912863006/
It fixes issues with the 32 bit compare-swap instruction on
ARM64 and fixes a fragile tree shaking test that is sensitive
to which private methods are in the core libraries.
R=kustermann@google.com, vegorov@google.com
BUG=
Review-Url: https://codereview.chromium.org/2954453002 .
64 bit objects have 32 bits of free space in the header word.
This is used for the hash code in string objects. We take it
for the default hash code on all objects that don't override
the hashCode getter.
This is both faster and a memory reduction. Eg it shaves about
70% off the running time of this microbenchmark:
List list = [];
class Thing {
get hashCode => 42;
}
class Thing2 {
get hashCode => 42;
}
class Thing3 { }
class Thing4 { }
main() {
int sum = 103;
for (int i = 0; i < 10000000; i++) {
list = [];
list.add("foo");
list.add(123);
list.add(1.23);
list.add(new Object());
list.add(new Thing());
list.add(new Thing2());
list.add(new Thing3());
list.add(new Thing4());
for (int j = 0; j < 2; j++) {
sum ^= biz(list);
}
}
print(sum);
}
int biz(List list) {
int sum = 103;
for (var x in list) {
sum ^= x.hashCode;
}
return sum;
}
R=rmacnak@google.com, vegorov@google.com
BUG=
Review-Url: https://codereview.chromium.org/2912863006 .
- Refactor the JumpToExceptionHandle code so that it is now built from
two pieces: JumpToFrame and RunExceptionHandler.
- Refactor the Simulator::Longjmp() code so that it is no longer
exception-specific. Instead it uses the RunExceptionHandler stub.
This makes it so that the JumpToFrame stub and Simulator::JumpToFrame
have the same semantics. This will make it easier to land the Rewind
changes I am working on.
There are some oddities for dbc.
BUG=
R=johnmccutchan@google.com
Review URL: https://codereview.chromium.org/2503653002 .
i.e. #ifndef VM_WHATEVER -> #ifndef RUNTIME_VM_WHATEVER
This lets us remove a hack from the PRESUBMIT.py script that existed
for reasons that are no longer valid, and sets us up to add some
presubmit checks for the GN build.
R=asiva@google.com, rmacnak@google.com
Review URL: https://codereview.chromium.org/2450713004 .
- Fix setting exit frame info to indicate when we are executing Dart code.
- Copy local pc to memory on call and return to make it accessible to the profiler. Since the profiler cannot access the local pc, the profiler is not accurate at the instruction level.
- Teach the profiler's stack walker that the stack grows up for Dart frames on DBC.
R=johnmccutchan@google.com
Review URL: https://codereview.chromium.org/2250823002 .
Ryan Macnak