heap: Inline fast paths for AllocateRaw() and AllocateRawWith()

- Both paths are now inlined.
- Outline large object allocation, shrinking trampoline a bit.
- Support a fast path for AllocationType::kOld from AllocateRawWith().

Bug: v8:12615, chromium:1293284
Change-Id: I8f0b9aabc6fe47e1eee159c214403ccffea5eeab
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3456082Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#79048}

src/heap/heap-inl.h

@@ -241,42 +241,42 @@ AllocationResult Heap::AllocateRaw(int size_in_bytes, AllocationType type,
   if (V8_ENABLE_THIRD_PARTY_HEAP_BOOL) {
     allocation = tp_heap_->Allocate(size_in_bytes, type, alignment);
   } else {
-    if (AllocationType::kYoung == type) {
-      if (large_object) {
-        allocation = new_lo_space_->AllocateRaw(size_in_bytes);
-      } else {
-        allocation = new_space_->AllocateRaw(size_in_bytes, alignment, origin);
-      }
-    } else if (AllocationType::kOld == type) {
-      if (large_object) {
-        allocation = lo_space_->AllocateRaw(size_in_bytes);
+    if (V8_UNLIKELY(large_object)) {
+      allocation =
+          AllocateRawLargeInternal(size_in_bytes, type, origin, alignment);
     } else {
-        allocation = old_space_->AllocateRaw(size_in_bytes, alignment, origin);
-      }
-    } else if (AllocationType::kCode == type) {
+      switch (type) {
+        case AllocationType::kYoung:
+          allocation =
+              new_space_->AllocateRaw(size_in_bytes, alignment, origin);
+          break;
+        case AllocationType::kOld:
+          allocation =
+              old_space_->AllocateRaw(size_in_bytes, alignment, origin);
+          break;
+        case AllocationType::kCode:
           DCHECK_EQ(alignment, AllocationAlignment::kTaggedAligned);
           DCHECK(AllowCodeAllocation::IsAllowed());
-      if (large_object) {
-        allocation = code_lo_space_->AllocateRaw(size_in_bytes);
-      } else {
           allocation = code_space_->AllocateRawUnaligned(size_in_bytes);
-      }
-    } else if (AllocationType::kMap == type) {
+          break;
+        case AllocationType::kMap:
           DCHECK_EQ(alignment, AllocationAlignment::kTaggedAligned);
           allocation = map_space_->AllocateRawUnaligned(size_in_bytes);
-    } else if (AllocationType::kReadOnly == type) {
-      DCHECK(!large_object);
+          break;
+        case AllocationType::kReadOnly:
           DCHECK(CanAllocateInReadOnlySpace());
           DCHECK_EQ(AllocationOrigin::kRuntime, origin);
           allocation = read_only_space_->AllocateRaw(size_in_bytes, alignment);
-    } else if (AllocationType::kSharedOld == type) {
-      allocation =
-          shared_old_allocator_->AllocateRaw(size_in_bytes, alignment, origin);
-    } else if (AllocationType::kSharedMap == type) {
-      allocation =
-          shared_map_allocator_->AllocateRaw(size_in_bytes, alignment, origin);
-    } else {
-      UNREACHABLE();
+          break;
+        case AllocationType::kSharedMap:
+          allocation = shared_map_allocator_->AllocateRaw(size_in_bytes,
+                                                          alignment, origin);
+          break;
+        case AllocationType::kSharedOld:
+          allocation = shared_old_allocator_->AllocateRaw(size_in_bytes,
+                                                          alignment, origin);
+          break;
+      }
     }
   }
 
@@ -317,21 +317,15 @@ HeapObject Heap::AllocateRawWith(int size, AllocationType allocation,
   DCHECK(AllowHandleAllocation::IsAllowed());
   DCHECK(AllowHeapAllocation::IsAllowed());
   DCHECK_EQ(gc_state(), NOT_IN_GC);
-  Heap* heap = isolate()->heap();
-  if (allocation == AllocationType::kYoung &&
-      alignment == AllocationAlignment::kTaggedAligned &&
-      size <= MaxRegularHeapObjectSize(allocation) &&
-      V8_LIKELY(!FLAG_single_generation && FLAG_inline_new &&
-                FLAG_gc_interval == -1)) {
-    Address* top = heap->NewSpaceAllocationTopAddress();
-    Address* limit = heap->NewSpaceAllocationLimitAddress();
-    if (*limit - *top >= static_cast<unsigned>(size)) {
-      DCHECK(IsAligned(size, kTaggedSize));
-      HeapObject obj = HeapObject::FromAddress(*top);
-      *top += size;
-      MSAN_ALLOCATED_UNINITIALIZED_MEMORY(obj.address(), size);
-      return obj;
-    }
+  if (allocation == AllocationType::kYoung) {
+    auto result = AllocateRaw(size, AllocationType::kYoung, origin, alignment);
+    HeapObject object;
+    if (result.To(&object)) return object;
+
+  } else if (allocation == AllocationType::kOld) {
+    auto result = AllocateRaw(size, AllocationType::kOld, origin, alignment);
+    HeapObject object;
+    if (result.To(&object)) return object;
   }
   switch (mode) {
     case kLightRetry:

src/heap/heap.cc

@@ -5648,6 +5648,26 @@ HeapObject Heap::AllocateRawWithLightRetrySlowPath(
   return HeapObject();
 }
 
+AllocationResult Heap::AllocateRawLargeInternal(int size_in_bytes,
+                                                AllocationType allocation,
+                                                AllocationOrigin origin,
+                                                AllocationAlignment alignment) {
+  DCHECK_GT(size_in_bytes, MaxRegularHeapObjectSize(allocation));
+  switch (allocation) {
+    case AllocationType::kYoung:
+      return new_lo_space_->AllocateRaw(size_in_bytes);
+    case AllocationType::kOld:
+      return lo_space_->AllocateRaw(size_in_bytes);
+    case AllocationType::kCode:
+      return code_lo_space_->AllocateRaw(size_in_bytes);
+    case AllocationType::kMap:
+    case AllocationType::kReadOnly:
+    case AllocationType::kSharedMap:
+    case AllocationType::kSharedOld:
+      UNREACHABLE();
+  }
+}
+
 HeapObject Heap::AllocateRawWithRetryOrFailSlowPath(
     int size, AllocationType allocation, AllocationOrigin origin,
     AllocationAlignment alignment) {

src/heap/heap.h

@@ -2089,8 +2089,15 @@ class Heap {
   // hardware and OS allow.  This is the single choke-point for allocations
   // performed by the runtime and should not be bypassed (to extend this to
   // inlined allocations, use the Heap::DisableInlineAllocation() support).
-  V8_WARN_UNUSED_RESULT inline AllocationResult AllocateRaw(
-      int size_in_bytes, AllocationType allocation,
+  V8_WARN_UNUSED_RESULT V8_INLINE AllocationResult
+  AllocateRaw(int size_in_bytes, AllocationType allocation,
+              AllocationOrigin origin = AllocationOrigin::kRuntime,
+              AllocationAlignment alignment = kTaggedAligned);
+
+  // Allocates an uninitialized large object. Used as dispatch by
+  // `AllocateRaw()` for large objects. Do not call this from anywhere else.
+  V8_EXPORT_PRIVATE V8_WARN_UNUSED_RESULT AllocationResult
+  AllocateRawLargeInternal(int size_in_bytes, AllocationType allocation,
                            AllocationOrigin origin = AllocationOrigin::kRuntime,
                            AllocationAlignment alignment = kTaggedAligned);
 
@@ -2098,8 +2105,8 @@ class Heap {
   // otherwise it falls back to a slower path indicated by the mode.
   enum AllocationRetryMode { kLightRetry, kRetryOrFail };
   template <AllocationRetryMode mode>
-  V8_WARN_UNUSED_RESULT inline HeapObject AllocateRawWith(
-      int size, AllocationType allocation,
+  V8_WARN_UNUSED_RESULT V8_INLINE HeapObject
+  AllocateRawWith(int size, AllocationType allocation,
                   AllocationOrigin origin = AllocationOrigin::kRuntime,
                   AllocationAlignment alignment = kTaggedAligned);