From 852c865dc90df7411cb3ce42c23adacdcdf99a9d Mon Sep 17 00:00:00 2001
From: Yaroslav Yamshchikov <y.yamshchiko@samsung.com>
Date: Sat, 15 Feb 2020 00:11:01 +0300
Subject: [PATCH] fix infinite recursion in crossgen2 on ARM (#32227)

---
 .../TypeSystem/Common/MetadataFieldLayoutAlgorithm.cs       | 13 +++++++++----
 .../Compiler/ReadyToRunMetadataFieldLayoutAlgorithm.cs      |  5 +++--
 2 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/src/coreclr/src/tools/Common/TypeSystem/Common/MetadataFieldLayoutAlgorithm.cs b/src/coreclr/src/tools/Common/TypeSystem/Common/MetadataFieldLayoutAlgorithm.cs
index b0be4b8..596bca5 100644
--- a/src/coreclr/src/tools/Common/TypeSystem/Common/MetadataFieldLayoutAlgorithm.cs
+++ b/src/coreclr/src/tools/Common/TypeSystem/Common/MetadataFieldLayoutAlgorithm.cs
@@ -425,7 +425,7 @@ namespace Internal.TypeSystem
             return computedLayout;
         }
 
-        protected virtual void AlignBaseOffsetIfNecessary(MetadataType type, ref LayoutInt baseOffset)
+        protected virtual void AlignBaseOffsetIfNecessary(MetadataType type, ref LayoutInt baseOffset, bool requiresAlign8)
         {
         }
 
@@ -434,8 +434,6 @@ namespace Internal.TypeSystem
             // For types inheriting from another type, field offsets continue on from where they left off
             LayoutInt cumulativeInstanceFieldPos = ComputeBytesUsedInParentType(type);
 
-            AlignBaseOffsetIfNecessary(type, ref cumulativeInstanceFieldPos);
-
             var layoutMetadata = type.GetClassLayout();
 
             int packingSize = ComputePackingSize(type, layoutMetadata);
@@ -459,6 +457,7 @@ namespace Internal.TypeSystem
                     continue;
 
                 TypeDesc fieldType = field.FieldType;
+
                 if (IsByValueClass(fieldType))
                 {
                     instanceValueClassFieldCount++;
@@ -495,6 +494,7 @@ namespace Internal.TypeSystem
             // Reset the counters to be used later as the index to insert into the array
             instanceGCPointerFieldsCount = 0;
             instanceValueClassFieldCount = 0;
+            LayoutInt largestAlignmentRequired = LayoutInt.One;
 
             // Iterate over all fields and do the following
             //   - Add instance fields to the appropriate array (while maintaining the enumerated order)
@@ -506,6 +506,9 @@ namespace Internal.TypeSystem
 
                 TypeDesc fieldType = field.FieldType;
 
+                var fieldSizeAndAlignment = ComputeFieldSizeAndAlignment(fieldType, packingSize);
+                largestAlignmentRequired = LayoutInt.Max(fieldSizeAndAlignment.Alignment, largestAlignmentRequired);
+
                 if (IsByValueClass(fieldType))
                 {
                     instanceValueClassFieldsArr[instanceValueClassFieldCount++] = field;
@@ -516,12 +519,14 @@ namespace Internal.TypeSystem
                 }
                 else
                 {
-                    var fieldSizeAndAlignment = ComputeFieldSizeAndAlignment(fieldType, packingSize);
                     int log2size = CalculateLog2(fieldSizeAndAlignment.Size.AsInt);
                     instanceNonGCPointerFieldsArr[log2size][instanceNonGCPointerFieldsCount[log2size]++] = field;
                 }
             }
 
+            largestAlignmentRequired = type.Context.Target.GetObjectAlignment(largestAlignmentRequired);
+            AlignBaseOffsetIfNecessary(type, ref cumulativeInstanceFieldPos, largestAlignmentRequired.AsInt > 4);
+
             // We've finished placing the fields into their appropriate arrays
             // The next optimization may place non-GC Pointers, so repurpose our
             // counter to keep track of the next non-GC Pointer that must be placed
diff --git a/src/coreclr/src/tools/crossgen2/ILCompiler.ReadyToRun/Compiler/ReadyToRunMetadataFieldLayoutAlgorithm.cs b/src/coreclr/src/tools/crossgen2/ILCompiler.ReadyToRun/Compiler/ReadyToRunMetadataFieldLayoutAlgorithm.cs
index b624439..5079e20 100644
--- a/src/coreclr/src/tools/crossgen2/ILCompiler.ReadyToRun/Compiler/ReadyToRunMetadataFieldLayoutAlgorithm.cs
+++ b/src/coreclr/src/tools/crossgen2/ILCompiler.ReadyToRun/Compiler/ReadyToRunMetadataFieldLayoutAlgorithm.cs
@@ -810,7 +810,7 @@ namespace ILCompiler
         /// This method decides whether the type needs aligned base offset in order to have layout resilient to 
         /// base class layout changes.
         /// </summary>
-        protected override void AlignBaseOffsetIfNecessary(MetadataType type, ref LayoutInt baseOffset)
+        protected override void AlignBaseOffsetIfNecessary(MetadataType type, ref LayoutInt baseOffset, bool requiresAlign8)
         {
             if (type.IsValueType)
             {
@@ -837,7 +837,8 @@ namespace ILCompiler
             }
 
             LayoutInt alignment = new LayoutInt(type.Context.Target.PointerSize);
-            if (type.RequiresAlign8())
+
+            if (requiresAlign8)
             {
                 alignment = new LayoutInt(8);
             }
-- 
2.7.4