Bug 1591276 - Refactor code to reallocate malloced buffers associated with nursery cells r=sfink

Differential Revision: https://phabricator.services.mozilla.com/D71041

--HG--
extra : moz-landing-system : lando

js/src/gc/Nursery-inl.h

@@ -131,7 +131,7 @@ static inline T* ReallocateObjectBuffer(JSContext* cx, JSObject* obj,
     return obj->zone()->pod_realloc<T>(oldBuffer, oldCount, newCount);
   }
   T* buffer = static_cast<T*>(cx->nursery().reallocateBuffer(
-      obj, oldBuffer, oldCount * sizeof(T), newCount * sizeof(T)));
+      obj->zone(), obj, oldBuffer, oldCount * sizeof(T), newCount * sizeof(T)));
   if (!buffer) {
     ReportOutOfMemory(cx);
   }
@@ -154,12 +154,12 @@ static inline JS::BigInt::Digit* AllocateBigIntDigits(JSContext* cx,
 }
 
 static inline JS::BigInt::Digit* ReallocateBigIntDigits(
-    JSContext* cx, JS::BigInt* obj, JS::BigInt::Digit* oldDigits,
+    JSContext* cx, JS::BigInt* bi, JS::BigInt::Digit* oldDigits,
     uint32_t oldLength, uint32_t newLength) {
   if (cx->isHelperThreadContext()) {
     MOZ_ASSERT(!cx->nursery().isInside(oldDigits));
-    return obj->zone()->pod_realloc<JS::BigInt::Digit>(oldDigits, oldLength,
-                                                       newLength);
+    return bi->zone()->pod_realloc<JS::BigInt::Digit>(oldDigits, oldLength,
+                                                      newLength);
   }
 
   size_t oldBytes =
@@ -167,8 +167,8 @@ static inline JS::BigInt::Digit* ReallocateBigIntDigits(
   size_t newBytes =
       RoundUp(newLength * sizeof(JS::BigInt::Digit), sizeof(Value));
 
-  auto* buffer = static_cast<JS::BigInt::Digit*>(
-      cx->nursery().reallocateBuffer(obj, oldDigits, oldBytes, newBytes));
+  auto* buffer = static_cast<JS::BigInt::Digit*>(cx->nursery().reallocateBuffer(
+      bi->zone(), bi, oldDigits, oldBytes, newBytes));
   if (!buffer) {
     ReportOutOfMemory(cx);
   }

js/src/gc/Nursery.cpp

@@ -625,16 +625,15 @@ void* js::Nursery::allocateZeroedBuffer(
   return allocateZeroedBuffer(obj->zone(), nbytes, arena);
 }
 
-void* js::Nursery::reallocateBuffer(JSObject* obj, void* oldBuffer,
+void* js::Nursery::reallocateBuffer(Zone* zone, Cell* cell, void* oldBuffer,
                                     size_t oldBytes, size_t newBytes) {
-  if (!IsInsideNursery(obj)) {
-    return obj->zone()->pod_realloc<uint8_t>((uint8_t*)oldBuffer, oldBytes,
-                                             newBytes);
+  if (!IsInsideNursery(cell)) {
+    return zone->pod_realloc<uint8_t>((uint8_t*)oldBuffer, oldBytes, newBytes);
   }
 
   if (!isInside(oldBuffer)) {
-    void* newBuffer = obj->zone()->pod_realloc<uint8_t>((uint8_t*)oldBuffer,
-                                                        oldBytes, newBytes);
+    void* newBuffer =
+        zone->pod_realloc<uint8_t>((uint8_t*)oldBuffer, oldBytes, newBytes);
     if (newBuffer && oldBuffer != newBuffer) {
       MOZ_ALWAYS_TRUE(mallocedBuffers.rekeyAs(oldBuffer, newBuffer, newBuffer));
     }
@@ -646,7 +645,7 @@ void* js::Nursery::reallocateBuffer(JSObject* obj, void* oldBuffer,
     return oldBuffer;
   }
 
-  void* newBuffer = allocateBuffer(obj->zone(), newBytes);
+  void* newBuffer = allocateBuffer(zone, newBytes);
   if (newBuffer) {
     PodCopy((uint8_t*)newBuffer, (uint8_t*)oldBuffer, oldBytes);
   }
@@ -663,34 +662,6 @@ void* js::Nursery::allocateBuffer(JS::BigInt* bi, size_t nbytes) {
   return allocateBuffer(bi->zone(), nbytes);
 }
 
-void* js::Nursery::reallocateBuffer(JS::BigInt* bi, void* oldDigits,
-                                    size_t oldBytes, size_t newBytes) {
-  if (!IsInsideNursery(bi)) {
-    return bi->zone()->pod_realloc<uint8_t>((uint8_t*)oldDigits, oldBytes,
-                                            newBytes);
-  }
-
-  if (!isInside(oldDigits)) {
-    void* newDigits = bi->zone()->pod_realloc<uint8_t>((uint8_t*)oldDigits,
-                                                       oldBytes, newBytes);
-    if (newDigits && oldDigits != newDigits) {
-      MOZ_ALWAYS_TRUE(mallocedBuffers.rekeyAs(oldDigits, newDigits, newDigits));
-    }
-    return newDigits;
-  }
-
-  // The nursery cannot make use of the returned digits data.
-  if (newBytes < oldBytes) {
-    return oldDigits;
-  }
-
-  void* newDigits = allocateBuffer(bi->zone(), newBytes);
-  if (newDigits) {
-    PodCopy((uint8_t*)newDigits, (uint8_t*)oldDigits, oldBytes);
-  }
-  return newDigits;
-}
-
 void js::Nursery::freeBuffer(void* buffer) {
   if (!isInside(buffer)) {
     removeMallocedBuffer(buffer);

js/src/gc/Nursery.h

@@ -308,18 +308,14 @@ class Nursery {
   void* allocateZeroedBuffer(JSObject* obj, size_t nbytes,
                              arena_id_t arena = js::MallocArena);
 
-  // Resize an existing object buffer.
-  void* reallocateBuffer(JSObject* obj, void* oldBuffer, size_t oldBytes,
-                         size_t newBytes);
+  // Resize an existing buffer.
+  void* reallocateBuffer(JS::Zone* zone, gc::Cell* cell, void* oldBuffer,
+                         size_t oldBytes, size_t newBytes);
 
   // Allocate a digits buffer for a given BigInt, using the nursery if possible
   // and |bi| is in the nursery.
   void* allocateBuffer(JS::BigInt* bi, size_t nbytes);
 
-  // Resize an existing BigInt digits buffer.
-  void* reallocateBuffer(JS::BigInt* bi, void* oldDigits, size_t oldBytes,
-                         size_t newBytes);
-
   // Free an object buffer.
   void freeBuffer(void* buffer);