Ignore off page malloc for non-layout too (#33)

gc.go

@@ -16,6 +16,7 @@ import (
 
 void* GC_malloc(unsigned int size);
 void* GC_malloc_atomic(unsigned int size);
+void* GC_malloc_ignore_off_page(unsigned int size);
 void* GC_malloc_explicitly_typed(unsigned int size, unsigned int gc_descr);
 void* GC_malloc_explicitly_typed_ignore_off_page(unsigned int size, unsigned int gc_descr);
 void* GC_calloc_explicitly_typed(unsigned int nelements, unsigned int element_size, unsigned int gc_descr);
@@ -38,6 +39,7 @@ import "C"
 
 const (
 	gcEventStart = 0
+	bigObjSize   = 100 * 1024
 )
 
 const (
@@ -101,7 +103,11 @@ func alloc(size uintptr, layoutPtr unsafe.Pointer) unsafe.Pointer {
 		buf = allocSmall(size, layoutSz, layoutBm)
 	} else if layoutPtr == nil {
 		// Unknown layout, assume all pointers.
-		buf = C.GC_malloc(C.uint(size))
+		if size >= bigObjSize {
+			buf = C.GC_malloc_ignore_off_page(C.uint(size))
+		} else {
+			buf = C.GC_malloc(C.uint(size))
+		}
 	} else {
 		buf = allocLarge(size, layoutPtr)
 	}
@@ -142,7 +148,7 @@ func allocTyped(allocSz uintptr, layoutSz uintptr, desc uintptr) unsafe.Pointer
 		// A bit unsure what the difference is, but it is recommended by bdwgc and seems to make a big
 		// difference in some apps.
 		// https://github.com/ivmai/bdwgc/blob/master/README.md#the-c-interface-to-the-allocator
-		if allocSz >= 100*1024 {
+		if allocSz >= bigObjSize {
 			return C.GC_malloc_explicitly_typed_ignore_off_page(C.uint(allocSz), C.uint(desc))
 		}
 		return C.GC_malloc_explicitly_typed(C.uint(allocSz), C.uint(desc))