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Revert "[vm, gc] Mark through new-space."

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This reverts commit a3b7c323b0.

Reason for revert: We are seeing crashes in some internal testing
si_signo=Segmentation fault(11), si_code=SEGV_ACCERR(2), si_addr=0x7f1cadb85bc6
version=3.3.0-edge+google3-v2 (google3) (google3) on "linux_x64"
pid=8967, thread=8969, isolate_group=main(0x5583571aaaf0), isolate=(nil)((nil))
os=linux, arch=x64, comp=no, sim=no
isolate_instructions=7f1cad8b7e40, vm_instructions=7f1cad8b1000
fp=7f1cacc7ebc0, sp=7f1cacc7eb90, pc=5583568155bc
  pc 0x00005583568155bc fp 0x00007f1cacc7ebc0 dart::MarkingVisitorBase<true>::VisitPointers(dart::ObjectPtr*, dart::ObjectPtr*)+0x15c
  pc 0x0000558356975a1d fp 0x00007f1cacc7ec60 dart::StackFrame::VisitObjectPointers(dart::ObjectPointerVisitor*)+0x1bd
  pc 0x0000558356935c29 fp 0x00007f1cacc7ecc0 dart::UntaggedSuspendState::VisitSuspendStatePointers(dart::SuspendStatePtr, dart::ObjectPointerVisitor*)+0x89
  pc 0x0000558356815948 fp 0x00007f1cacc7ed10 dart::MarkingVisitorBase<true>::DrainMarkingStackWithPauseChecks()+0x128
  pc 0x0000558356815749 fp 0x00007f1cacc7ed80 dart::ConcurrentMarkTask::Run()+0x69

Original change's description:
> [vm, gc] Mark through new-space.
>
>  - Initial and final marking no longer visit all of new-space, reducing the STW pause for major GC.
>  - A scavenge during concurrent marking must forward / filter objects in the marking worklist that are moved / collected, increasing the STW pause for minor GC.
>  - Unreachable intergenerational cycles and weak references are collected in the next mark-sweep instead of first requiring enough scavenges to promote the whole cycle or weak target into old-space.
>  - Artificial minor GCs are no longer needed to avoid memory leaks from back-to-back major GCs.
>  - reachabilityBarrier is now just a count of major GCs.
>
> TEST=ci
> Change-Id: Ic7754e8d972763654eae2b7faa8670735d9cda3f
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/340644
> Reviewed-by: Siva Annamalai <asiva@google.com>
> Commit-Queue: Ryan Macnak <rmacnak@google.com>

Change-Id: Ice07b4eb5bef3b41c9618ef0ca7759de006ffe00
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/343060
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Commit-Queue: Siva Annamalai <asiva@google.com>
Reviewed-by: Alexander Aprelev <aam@google.com>
This commit is contained in:
Siva Annamalai
2023-12-21 21:02:38 +00:00
committed by Commit Queue
parent ecb662c9cd
commit 94c8d341d7
44 changed files with 523 additions and 910 deletions
Download Patch File Download Diff File Expand all files Collapse all files
runtime/vm/compiler/stub_code_compiler_arm.cc
+8 -10
View File
@@ -37,14 +37,11 @@ namespace compiler {
// WARNING: This might clobber all registers except for [R0], [THR] and [FP].
// The caller should simply call LeaveStubFrame() and return.
void StubCodeCompiler::EnsureIsNewOrRemembered() {
// If the object is not in an active TLAB, we call a leaf-runtime to add it to
// the remembered set and/or deferred marking worklist. This test assumes a
// Page's TLAB use is always ascending.
// If the object is not remembered we call a leaf-runtime to add it to the
// remembered set.
Label done;
__ AndImmediate(TMP, R0, target::kPageMask);
__ LoadFromOffset(TMP, Address(TMP, target::Page::original_top_offset()));
__ CompareRegisters(R0, TMP);
__ BranchIf(UNSIGNED_GREATER_EQUAL, &done);
__ tst(R0, Operand(1 << target::ObjectAlignment::kNewObjectBitPosition));
__ BranchIf(NOT_ZERO, &done);
{
LeafRuntimeScope rt(assembler,
@@ -1683,16 +1680,16 @@ static void GenerateWriteBarrierStubHelper(Assembler* assembler,
__ b(&skip_marking, ZERO);
{
// Atomically clear kNotMarkedBit.
// Atomically clear kOldAndNotMarkedBit.
Label retry, done;
__ PushList((1 << R2) | (1 << R3) | (1 << R4)); // Spill.
__ AddImmediate(R3, R0, target::Object::tags_offset() - kHeapObjectTag);
// R3: Untagged address of header word (ldrex/strex do not support offsets).
__ Bind(&retry);
__ ldrex(R2, R3);
__ tst(R2, Operand(1 << target::UntaggedObject::kNotMarkedBit));
__ tst(R2, Operand(1 << target::UntaggedObject::kOldAndNotMarkedBit));
__ b(&done, ZERO); // Marked by another thread.
__ bic(R2, R2, Operand(1 << target::UntaggedObject::kNotMarkedBit));
__ bic(R2, R2, Operand(1 << target::UntaggedObject::kOldAndNotMarkedBit));
__ strex(R4, R2, R3);
__ cmp(R4, Operand(1));
__ b(&retry, EQ);
@@ -1716,6 +1713,7 @@ static void GenerateWriteBarrierStubHelper(Assembler* assembler,
__ Bind(&done);
__ clrex();
__ PopList((1 << R2) | (1 << R3) | (1 << R4)); // Unspill.
__ Ret();
}
Label add_to_remembered_set, remember_card;