[stackguard] Add "HasTerminationRequest" function

We sometimes have a need to check for termination requests
while we're in the middle of non-GC-safe computations, so
we can't do a full "HandleInterrupts" (which could do GC).
This CL adds a separate function to check for termination
requests (but no other interrupt reasons) in such cases.

Bug: v8:9877, v8:11515
Change-Id: I431dba193a07ba63003794639e5d3630470d6ee7
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2739587
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Auto-Submit: Jakob Kummerow <jkummerow@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#73256}

src/execution/stack-guard.cc

@@ -157,6 +157,16 @@ void StackGuard::ClearInterrupt(InterruptFlag flag) {
   if (!has_pending_interrupts(access)) reset_limits(access);
 }
 
+bool StackGuard::HasTerminationRequest() {
+  ExecutionAccess access(isolate_);
+  if ((thread_local_.interrupt_flags_ & TERMINATE_EXECUTION) != 0) {
+    thread_local_.interrupt_flags_ &= ~TERMINATE_EXECUTION;
+    if (!has_pending_interrupts(access)) reset_limits(access);
+    return true;
+  }
+  return false;
+}
+
 int StackGuard::FetchAndClearInterrupts() {
   ExecutionAccess access(isolate_);
 

src/execution/stack-guard.h

@@ -90,6 +90,11 @@ class V8_EXPORT_PRIVATE V8_NODISCARD StackGuard final {
   // stack overflow, then handle the interruption accordingly.
   Object HandleInterrupts();
 
+  // Special case of {HandleInterrupts}: checks for termination requests only.
+  // This is guaranteed to never cause GC, so can be used to interrupt
+  // long-running computations that are not GC-safe.
+  bool HasTerminationRequest();
+
   static constexpr int kSizeInBytes = 7 * kSystemPointerSize;
 
   static char* Iterate(RootVisitor* v, char* thread_storage) {