Do more to avoid last-resort stop-the-world GC

src/heap/heap-inl.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_HEAP_HEAP_INL_H_
 #define V8_HEAP_HEAP_INL_H_
 
 #include <cmath>
 
 #include "src/base/platform/platform.h"
@@ skipping 520 matching lines @@
   if (__allocation__.To(&__object__)) {                   \
     DCHECK(__object__ != (ISOLATE)->heap()->exception()); \
     RETURN_VALUE;                                         \
   }
 
 #define CALL_AND_RETRY(ISOLATE, FUNCTION_CALL, RETURN_VALUE, RETURN_EMPTY)    \
   do {                                                                        \
     AllocationResult __allocation__ = FUNCTION_CALL;                          \
     Object* __object__ = NULL;                                                \
     RETURN_OBJECT_UNLESS_RETRY(ISOLATE, RETURN_VALUE)                         \
-    (ISOLATE)->heap()->CollectGarbage(__allocation__.RetrySpace(),            \
-                                      "allocation failure");                  \
-    __allocation__ = FUNCTION_CALL;                                           \
-    RETURN_OBJECT_UNLESS_RETRY(ISOLATE, RETURN_VALUE)                         \
+    /* Two GCs before panicking.  In newspace will almost always succeed. */  \
+    for (int __i__ = 0; __i__ < 2; __i__++) {                                 \
+      (ISOLATE)->heap()->CollectGarbage(__allocation__.RetrySpace(),          \
+                                        "allocation failure");                \
+      __allocation__ = FUNCTION_CALL;                                         \
+      RETURN_OBJECT_UNLESS_RETRY(ISOLATE, RETURN_VALUE)                       \
+    }                                                                         \
     (ISOLATE)->counters()->gc_last_resort_from_handles()->Increment();        \
     (ISOLATE)->heap()->CollectAllAvailableGarbage("last resort gc");          \
     {                                                                         \
       AlwaysAllocateScope __scope__(ISOLATE);                                 \
       __allocation__ = FUNCTION_CALL;                                         \
     }                                                                         \
     RETURN_OBJECT_UNLESS_RETRY(ISOLATE, RETURN_VALUE)                         \
     /* TODO(1181417): Fix this. */                                            \
     v8::internal::Heap::FatalProcessOutOfMemory("CALL_AND_RETRY_LAST", true); \
     RETURN_EMPTY;                                                             \
@@ skipping 123 matching lines @@
 
 void VerifySmisVisitor::VisitPointers(Object** start, Object** end) {
   for (Object** current = start; current < end; current++) {
     CHECK((*current)->IsSmi());
   }
 }
 }
 }  // namespace v8::internal
 
 #endif  // V8_HEAP_HEAP_INL_H_