[NativeAOT] Move RequiresAlign8 flag from RareFlags into ExtendedFlags (

#106010)
dotnet · Aug 7, 2024 · 4153092 · 4153092
1 parent 1716c4b
commit 4153092
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Showing 6 changed files with 26 additions and 12 deletions.
diff --git a/src/coreclr/nativeaot/Common/src/Internal/Runtime/MethodTable.cs b/src/coreclr/nativeaot/Common/src/Internal/Runtime/MethodTable.cs
@@ -732,7 +732,14 @@ internal bool RequiresAlign8
         {
             get
             {
-                return (RareFlags & EETypeRareFlags.RequiresAlign8Flag) != 0;
+                // NOTE: Does not work for types with HasComponentSize, ie. arrays and strings.
+                // Since this is called early through RhNewObject we cannot use regular Debug.Assert
+                // here to enforce the assumption.
+#if DEBUG
+                if (HasComponentSize)
+                    Debug.Fail("RequiresAlign8 called for array or string");
+#endif
+                return (_uFlags & (uint)EETypeFlagsEx.RequiresAlign8Flag) != 0;
             }
         }
 

diff --git a/src/coreclr/nativeaot/Runtime.Base/src/System/Runtime/RuntimeExports.cs b/src/coreclr/nativeaot/Runtime.Base/src/System/Runtime/RuntimeExports.cs
@@ -61,7 +61,8 @@ public static unsafe object RhNewArray(MethodTable* pEEType, int length)
             Debug.Assert(pEEType->IsArray || pEEType->IsString);
 
 #if FEATURE_64BIT_ALIGNMENT
-            if (pEEType->RequiresAlign8)
+            MethodTable* pEEElementType = pEEType->RelatedParameterType;
+            if (pEEElementType->IsValueType && pEEElementType->RequiresAlign8)
             {
                 return InternalCalls.RhpNewArrayAlign8(pEEType, length);
             }
@@ -381,7 +382,8 @@ internal static unsafe IntPtr RhGetRuntimeHelperForType(MethodTable* pEEType, Ru
 
                 case RuntimeHelperKind.AllocateArray:
 #if FEATURE_64BIT_ALIGNMENT
-                    if (pEEType->RequiresAlign8)
+                    MethodTable* pEEElementType = pEEType->RelatedParameterType;
+                    if (pEEElementType->IsValueType && pEEElementType->RequiresAlign8)
                         return (IntPtr)(delegate*<MethodTable*, int, object>)&InternalCalls.RhpNewArrayAlign8;
 #endif // FEATURE_64BIT_ALIGNMENT
 

diff --git a/src/coreclr/nativeaot/Runtime/inc/MethodTable.h b/src/coreclr/nativeaot/Runtime/inc/MethodTable.h
@@ -161,6 +161,9 @@ class MethodTable
         // GC depends on this bit, this type has a critical finalizer
         HasCriticalFinalizerFlag = 0x0002,
         IsTrackedReferenceWithFinalizerFlag = 0x0004,
+
+        // This type requires 8-byte alignment for its fields on certain platforms (ARM32, WASM)
+        RequiresAlign8Flag = 0x1000
     };
 
 public:

diff --git a/src/coreclr/tools/Common/Internal/Runtime/EETypeBuilderHelpers.cs b/src/coreclr/tools/Common/Internal/Runtime/EETypeBuilderHelpers.cs
@@ -128,6 +128,11 @@ mdType.Name is "WeakReference" or "WeakReference`1" &&
                 flagsEx |= (ushort)EETypeFlagsEx.IDynamicInterfaceCastableFlag;
             }
 
+            if (type.RequiresAlign8())
+            {
+                flagsEx |= (ushort)EETypeFlagsEx.RequiresAlign8Flag;
+            }
+
             return flagsEx;
         }
 

diff --git a/src/coreclr/tools/Common/Internal/Runtime/MethodTable.Constants.cs b/src/coreclr/tools/Common/Internal/Runtime/MethodTable.Constants.cs
@@ -84,6 +84,11 @@ internal enum EETypeFlagsEx : ushort
         /// This type implements IDynamicInterfaceCastable to allow dynamic resolution of interface casts.
         /// </summary>
         IDynamicInterfaceCastableFlag = 0x0008,
+
+        /// <summary>
+        /// This type requires 8-byte alignment for its fields on certain platforms (ARM32, WASM)
+        /// </summary>
+        RequiresAlign8Flag = 0x1000
     }
 
     internal enum EETypeKind : uint
@@ -116,10 +121,7 @@ internal enum EETypeKind : uint
     [Flags]
     internal enum EETypeRareFlags : int
     {
-        /// <summary>
-        /// This type requires 8-byte alignment for its fields on certain platforms (only ARM currently).
-        /// </summary>
-        RequiresAlign8Flag = 0x00000001,
+        // UNUSED = 0x00000001,
 
         // UNUSED1 = 0x00000002,
 

diff --git a/src/coreclr/tools/aot/ILCompiler.Compiler/Compiler/DependencyAnalysis/EETypeNode.cs b/src/coreclr/tools/aot/ILCompiler.Compiler/Compiler/DependencyAnalysis/EETypeNode.cs
@@ -1352,11 +1352,6 @@ private void ComputeRareFlags()
         {
             uint flags = 0;
 
-            if (_type.RequiresAlign8())
-            {
-                flags |= (uint)EETypeRareFlags.RequiresAlign8Flag;
-            }
-
             if (_type.IsByRefLike)
             {
                 flags |= (uint)EETypeRareFlags.IsByRefLikeFlag;