Deduplicate __arraySetAllocLength. The only difference really is how we

get the typeinfo to store, and how we get the fact that a finalizer is present or not.
dlang · Nov 18, 2024 · 7314c9a · 7314c9a
1 parent 613394c
commit 7314c9a
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Showing 2 changed files with 9 additions and 108 deletions.
diff --git a/druntime/src/core/internal/array/utils.d b/druntime/src/core/internal/array/utils.d
@@ -263,111 +263,7 @@ void *__arrayStart()(return scope BlkInfo info) nothrow pure
  */
 bool __setArrayAllocLength(T)(ref BlkInfo info, size_t newLength, bool isShared, size_t oldLength = ~0)
 {
-    import core.atomic;
     import core.lifetime : TypeInfoSize;
-
-    size_t typeInfoSize = TypeInfoSize!T;
-
-    if (info.size <= 256)
-    {
-        import core.checkedint;
-
-        bool overflow;
-        auto newLengthPadded = addu(newLength,
-                                     addu(SMALLPAD, typeInfoSize, overflow),
-                                     overflow);
-
-        if (newLengthPadded > info.size || overflow)
-            // new size does not fit inside block
-            return false;
-
-        auto length = cast(ubyte *)(info.base + info.size - typeInfoSize - SMALLPAD);
-        if (oldLength != ~0)
-        {
-            if (isShared)
-            {
-                return cas(cast(shared)length, cast(ubyte)oldLength, cast(ubyte)newLength);
-            }
-            else
-            {
-                if (*length == cast(ubyte)oldLength)
-                    *length = cast(ubyte)newLength;
-                else
-                    return false;
-            }
-        }
-        else
-        {
-            // setting the initial length, no cas needed
-            *length = cast(ubyte)newLength;
-        }
-        if (typeInfoSize)
-        {
-            auto typeInfo = cast(TypeInfo*)(info.base + info.size - size_t.sizeof);
-            *typeInfo = cast()typeid(T);
-        }
-    }
-    else if (info.size < PAGESIZE)
-    {
-        if (newLength + MEDPAD + typeInfoSize > info.size)
-            // new size does not fit inside block
-            return false;
-        auto length = cast(ushort *)(info.base + info.size - typeInfoSize - MEDPAD);
-        if (oldLength != ~0)
-        {
-            if (isShared)
-            {
-                return cas(cast(shared)length, cast(ushort)oldLength, cast(ushort)newLength);
-            }
-            else
-            {
-                if (*length == oldLength)
-                    *length = cast(ushort)newLength;
-                else
-                    return false;
-            }
-        }
-        else
-        {
-            // setting the initial length, no cas needed
-            *length = cast(ushort)newLength;
-        }
-        if (typeInfoSize)
-        {
-            auto typeInfo = cast(TypeInfo*)(info.base + info.size - size_t.sizeof);
-            *typeInfo = cast()typeid(T);
-        }
-    }
-    else
-    {
-        if (newLength + LARGEPAD > info.size)
-            // new size does not fit inside block
-            return false;
-        auto length = cast(size_t *)(info.base);
-        if (oldLength != ~0)
-        {
-            if (isShared)
-            {
-                return cas(cast(shared)length, cast(size_t)oldLength, cast(size_t)newLength);
-            }
-            else
-            {
-                if (*length == oldLength)
-                    *length = newLength;
-                else
-                    return false;
-            }
-        }
-        else
-        {
-            // setting the initial length, no cas needed
-            *length = newLength;
-        }
-        if (typeInfoSize)
-        {
-            auto typeInfo = cast(TypeInfo*)(info.base + size_t.sizeof);
-            *typeInfo = cast()typeid(T);
-        }
-    }
-    return true; // resize succeeded
+    import core.internal.gc.blockmeta : __setArrayAllocLengthImpl;
+    return __setArrayAllocLengthImpl(info, newLength, isShared, typeid(T), oldLength, TypeInfoSize!T);
 }
diff --git a/druntime/src/core/internal/gc/blockmeta.d b/druntime/src/core/internal/gc/blockmeta.d
@@ -71,9 +71,14 @@ size_t structTypeInfoSize(const TypeInfo ti) pure nothrow @nogc
   */
 bool __setArrayAllocLength(ref BlkInfo info, size_t newlength, bool isshared, const TypeInfo tinext, size_t oldlength = ~0) pure nothrow
 {
-    import core.atomic;
-
     size_t typeInfoSize = structTypeInfoSize(tinext);
+    return __setArrayAllocLengthImpl(info, newlength, isshared, tinext, oldlength, typeInfoSize);
+}
+
+// the impl function, used both above and in core.internal.array.utils
+bool __setArrayAllocLengthImpl(ref BlkInfo info, size_t newlength, bool isshared, const TypeInfo tinext, size_t oldlength, size_t typeInfoSize) pure nothrow
+{
+    import core.atomic;
 
     if (info.size <= 256)
     {