Bug 1665583 - Report OOM for off-thread buffer allocations r=tcampbell

I don't know why we never did this before.  And I guess it won't be needed when
we stop allocating GC things off-thread.

Differential Revision: https://phabricator.services.mozilla.com/D90701

js/src/gc/Nursery-inl.h

@@ -128,52 +128,64 @@ template <typename T>
 static inline T* ReallocateObjectBuffer(JSContext* cx, JSObject* obj,
                                         T* oldBuffer, uint32_t oldCount,
                                         uint32_t newCount) {
+  T* buffer;
   if (cx->isHelperThreadContext()) {
-    return obj->zone()->pod_realloc<T>(oldBuffer, oldCount, newCount);
+    buffer = obj->zone()->pod_realloc<T>(oldBuffer, oldCount, newCount);
+  } else {
+    buffer = static_cast<T*>(cx->nursery().reallocateBuffer(
+        obj->zone(), obj, oldBuffer, oldCount * sizeof(T),
+        newCount * sizeof(T)));
   }
-  auto* buffer = static_cast<T*>(cx->nursery().reallocateBuffer(
-      obj->zone(), obj, oldBuffer, oldCount * sizeof(T), newCount * sizeof(T)));
+
   if (!buffer) {
     ReportOutOfMemory(cx);
   }
+
   return buffer;
 }
 
 static inline JS::BigInt::Digit* AllocateBigIntDigits(JSContext* cx,
                                                       JS::BigInt* bi,
                                                       uint32_t length) {
+  JS::BigInt::Digit* digits;
   if (cx->isHelperThreadContext()) {
-    return cx->pod_malloc<JS::BigInt::Digit>(length);
+    digits = cx->pod_malloc<JS::BigInt::Digit>(length);
+  } else {
+    size_t nbytes = RoundUp(length * sizeof(JS::BigInt::Digit), sizeof(Value));
+    digits = static_cast<JS::BigInt::Digit*>(
+        cx->nursery().allocateBuffer(bi, nbytes));
   }
-  size_t nbytes = RoundUp(length * sizeof(JS::BigInt::Digit), sizeof(Value));
-  auto* digits =
-      static_cast<JS::BigInt::Digit*>(cx->nursery().allocateBuffer(bi, nbytes));
+
   if (!digits) {
     ReportOutOfMemory(cx);
   }
+
   return digits;
 }
 
 static inline JS::BigInt::Digit* ReallocateBigIntDigits(
     JSContext* cx, JS::BigInt* bi, JS::BigInt::Digit* oldDigits,
     uint32_t oldLength, uint32_t newLength) {
+  JS::BigInt::Digit* digits;
   if (cx->isHelperThreadContext()) {
     MOZ_ASSERT(!cx->nursery().isInside(oldDigits));
-    return bi->zone()->pod_realloc<JS::BigInt::Digit>(oldDigits, oldLength,
-                                                      newLength);
+    digits = bi->zone()->pod_realloc<JS::BigInt::Digit>(oldDigits, oldLength,
+                                                        newLength);
+  } else {
+    size_t oldBytes =
+        RoundUp(oldLength * sizeof(JS::BigInt::Digit), sizeof(Value));
+    size_t newBytes =
+        RoundUp(newLength * sizeof(JS::BigInt::Digit), sizeof(Value));
+
+    digits = static_cast<JS::BigInt::Digit*>(cx->nursery().reallocateBuffer(
+        bi->zone(), bi, oldDigits, oldBytes, newBytes));
   }
 
-  size_t oldBytes =
-      RoundUp(oldLength * sizeof(JS::BigInt::Digit), sizeof(Value));
-  size_t newBytes =
-      RoundUp(newLength * sizeof(JS::BigInt::Digit), sizeof(Value));
-
-  auto* buffer = static_cast<JS::BigInt::Digit*>(cx->nursery().reallocateBuffer(
-      bi->zone(), bi, oldDigits, oldBytes, newBytes));
-  if (!buffer) {
+  if (!digits) {
     ReportOutOfMemory(cx);
   }
-  return buffer;
+
+  return digits;
 }
 
 }  // namespace js

js/src/jit-test/tests/basic/bug-1665583.js

@@ -0,0 +1,40 @@
+// |jit-test| skip-if: !('oomTest' in this)
+
+function parseModule(source) {
+  offThreadCompileModule(source);
+  return finishOffThreadModule();
+}
+function loadFile(lfVarx) {
+  oomTest(function() {
+      parseModule(lfVarx);
+  });
+}
+loadFile(`
+const numberingSystems = {
+  "adlm": {},
+  "ahom": {},
+  "arab": {},
+  "arabext": {},
+  "armn": {},
+  "armnlow": {},
+  "bali": {},
+  "beng": {},
+  "bhks": {},
+  "brah": {},
+  "cakm": {},
+  "cham": {},
+  "cyrl": {},
+  "hmnp": {},
+  "java": {},
+  "jpan": {},
+  "jpanfin": {},
+  "jpanyear": {},
+  "knda": {},
+  "lana": {},
+  "latn": {},
+  "lepc": {},
+  "limb": {},
+  "wcho": {},
+  "extra1": {}
+};
+`);