Bring up hot-cold splitting on NativeAOT

src/coreclr/tools/Common/JitInterface/CorInfoImpl.cs

@@ -474,7 +474,7 @@ private void PublishCode()
                 , isFoldable: (_compilation._compilationOptions & RyuJitCompilationOptions.MethodBodyFolding) != 0
 #endif
                 );
-#if READYTORUN
+
             if (_methodColdCodeNode != null)
             {
                 var relocs2 = _coldCodeRelocs.ToArray();
@@ -484,9 +484,10 @@ private void PublishCode()
                     alignment,
                     new ISymbolDefinitionNode[] { _methodColdCodeNode });
                 _methodColdCodeNode.SetCode(coldObjectData);
+#if READYTORUN
                 _methodCodeNode.SetColdCodeNode(_methodColdCodeNode);
-            }
 #endif
+            }
 
             _methodCodeNode.InitializeFrameInfos(_frameInfos);
 #if READYTORUN
@@ -631,9 +632,8 @@ private void CompileMethodCleanup()
             }
 
             _methodCodeNode = null;
-#if READYTORUN
             _methodColdCodeNode = null;
-#endif
+
             _code = null;
             _coldCode = null;
 
@@ -642,18 +642,15 @@ private void CompileMethodCleanup()
 
             _codeRelocs = new ArrayBuilder<Relocation>();
             _roDataRelocs = new ArrayBuilder<Relocation>();
-#if READYTORUN
             _coldCodeRelocs = new ArrayBuilder<Relocation>();
-#endif
+
             _numFrameInfos = 0;
             _usedFrameInfos = 0;
             _frameInfos = null;
 
-#if READYTORUN
             _numColdFrameInfos = 0;
             _usedColdFrameInfos = 0;
             _coldFrameInfos = null;
-#endif
 
             _gcInfo = null;
             _ehClauses = null;
@@ -3313,11 +3310,9 @@ private bool getTailCallHelpers(ref CORINFO_RESOLVED_TOKEN callToken, CORINFO_SI
         private int _usedFrameInfos;
         private FrameInfo[] _frameInfos;
 
-#if READYTORUN
         private int _numColdFrameInfos;
         private int _usedColdFrameInfos;
         private FrameInfo[] _coldFrameInfos;
-#endif
 
         private byte[] _gcInfo;
         private CORINFO_EH_CLAUSE[] _ehClauses;
@@ -3329,10 +3324,7 @@ private void allocMem(ref AllocMemArgs args)
 
             if (args.coldCodeSize != 0)
             {
-
-#if READYTORUN
                 this._methodColdCodeNode = new MethodColdCodeNode(MethodBeingCompiled);
-#endif
                 args.coldCodeBlock = (void*)GetPin(_coldCode = new byte[args.coldCodeSize]);
                 args.coldCodeBlockRW = args.coldCodeBlock;
             }
@@ -3377,23 +3369,19 @@ private void allocMem(ref AllocMemArgs args)
                 _frameInfos = new FrameInfo[_numFrameInfos];
             }
 
-#if READYTORUN
             if (_numColdFrameInfos > 0)
             {
                 _coldFrameInfos = new FrameInfo[_numColdFrameInfos];
             }
-#endif
         }
 
         private void reserveUnwindInfo(bool isFunclet, bool isColdCode, uint unwindSize)
         {
-#if READYTORUN
             if (isColdCode)
             {
                 _numColdFrameInfos++;
             }
             else
-#endif
             {
                 _numFrameInfos++;
             }
@@ -3431,18 +3419,14 @@ private void allocUnwindInfo(byte* pHotCode, byte* pColdCode, uint startOffset,
                 blobData = CompressARM64CFI(blobData);
             }
 #endif
-#if READYTORUN
             if (pColdCode == null)
-#endif
             {
                 _frameInfos[_usedFrameInfos++] = new FrameInfo(flags, (int)startOffset, (int)endOffset, blobData);
             }
-#if READYTORUN
             else
             {
                 _coldFrameInfos[_usedColdFrameInfos++] = new FrameInfo(flags, (int)startOffset, (int)endOffset, blobData);
             }
-#endif
         }
 
         private void* allocGCInfo(UIntPtr size)
@@ -3477,9 +3461,7 @@ private void recordCallSite(uint instrOffset, CORINFO_SIG_INFO* callSig, CORINFO
 
         private ArrayBuilder<Relocation> _codeRelocs;
         private ArrayBuilder<Relocation> _roDataRelocs;
-#if READYTORUN
         private ArrayBuilder<Relocation> _coldCodeRelocs;
-#endif
 
         /// <summary>
         /// Various type of block.
@@ -3557,11 +3539,9 @@ private ref ArrayBuilder<Relocation> findRelocBlock(BlockType blockType, out int
                 case BlockType.ROData:
                     length = _roData.Length;
                     return ref _roDataRelocs;
-#if READYTORUN
                 case BlockType.ColdCode:
                     length = _coldCode.Length;
                     return ref _coldCodeRelocs;
-#endif
                 default:
                     throw new NotImplementedException("Arbitrary relocs");
             }
@@ -3635,13 +3615,9 @@ private void recordRelocation(void* location, void* locationRW, void* target, us
                     break;
 
                 case BlockType.ColdCode:
-#if READYTORUN
                     Debug.Assert(_methodColdCodeNode != null);
                     relocTarget = _methodColdCodeNode;
                     break;
-#else
-                    throw new NotImplementedException("ColdCode relocs");
-#endif
 
                 case BlockType.ROData:
                     relocTarget = _roDataBlob;

src/coreclr/tools/aot/ILCompiler.RyuJit/Compiler/DependencyAnalysis/MethodColdCodeNode.cs

@@ -0,0 +1,64 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using Internal.Text;
+using Internal.TypeSystem;
+using System.Diagnostics;
+using System;
+
+namespace ILCompiler.DependencyAnalysis
+{
+    public class MethodColdCodeNode : ObjectNode, ISymbolDefinitionNode
+    {
+        private ObjectData _methodColdCode;
+        private MethodDesc _owningMethod;
+
+        public MethodColdCodeNode(MethodDesc owningMethod)
+        {
+            _owningMethod = owningMethod;
+        }
+
+        public int Offset => 0;
+
+        public override ObjectNodeSection Section
+        {
+            get
+            {
+                return _owningMethod.Context.Target.IsWindows ? ObjectNodeSection.ManagedCodeWindowsContentSection : ObjectNodeSection.ManagedCodeUnixContentSection;
+
+            }
+        }
+
+        public override bool IsShareable => false;
+
+        public override int ClassCode => 788492408;
+
+        public override bool StaticDependenciesAreComputed => _methodColdCode != null;
+
+        public void AppendMangledName(NameMangler nameMangler, Utf8StringBuilder sb)
+        {
+            sb.Append("__coldcode_" + nameMangler.GetMangledMethodName(_owningMethod));
+        }
+
+        public override int CompareToImpl(ISortableNode other, CompilerComparer comparer)
+        {
+            MethodColdCodeNode otherNode = (MethodColdCodeNode)other;
+            return comparer.Compare(_owningMethod, otherNode._owningMethod);
+        }
+
+        public override ObjectData GetData(NodeFactory factory, bool relocsOnly = false) => _methodColdCode;
+
+        protected override string GetName(NodeFactory context) => throw new NotImplementedException();
+
+        public void SetCode(ObjectData data)
+        {
+            Debug.Assert(_methodColdCode == null);
+            _methodColdCode = data;
+        }
+
+        public int GetColdCodeSize()
+        {
+            return _methodColdCode.Data.Length;
+        }
+    }
+}

src/coreclr/tools/aot/ILCompiler.RyuJit/Compiler/RyuJitCompilation.cs

@@ -137,7 +137,8 @@ protected override void ComputeDependencyNodeDependencies(List<DependencyNodeCor
             }
             else
             {
-                CompileMultiThreaded(methodsToCompile);
+                CompileSingleThreaded(methodsToCompile);
+                // CompileMultiThreaded(methodsToCompile);
             }
         }
         private void CompileMultiThreaded(List<MethodCodeNode> methodsToCompile)

src/coreclr/tools/aot/ILCompiler.RyuJit/Compiler/RyuJitCompilationBuilder.cs

@@ -126,6 +126,9 @@ public override ICompilation ToCompilation()
             if (_resilient)
                 options |= RyuJitCompilationOptions.UseResilience;
 
+            // TODO: Andrew Au, Command line option
+            jitFlagBuilder.Add(CorJitFlag.CORJIT_FLAG_PROCSPLIT);
+
             var factory = new RyuJitNodeFactory(_context, _compilationGroup, _metadataManager, _interopStubManager, _nameMangler, _vtableSliceProvider, _dictionaryLayoutProvider, GetPreinitializationManager());
 
             JitConfigProvider.Initialize(_context.Target, jitFlagBuilder.ToArray(), _ryujitOptions, _jitPath);

src/coreclr/tools/aot/ILCompiler.RyuJit/ILCompiler.RyuJit.csproj

@@ -26,6 +26,7 @@
 
   <ItemGroup>
     <Compile Include="Compiler\DependencyAnalysis\MethodCodeNode.cs" />
+    <Compile Include="Compiler\DependencyAnalysis\MethodColdCodeNode.cs" />
     <Compile Include="Compiler\DependencyAnalysis\RyuJitNodeFactory.cs" />
     <Compile Include="Compiler\ProfileDataManager.cs" />
     <Compile Include="Compiler\RyuJitCompilation.cs" />

src/coreclr/tools/aot/ILCompiler.RyuJit/JitInterface/CorInfoImpl.RyuJit.cs

@@ -33,6 +33,7 @@ unsafe partial class CorInfoImpl
         private RyuJitCompilation _compilation;
         private MethodDebugInformation _debugInfo;
         private MethodCodeNode _methodCodeNode;
+        private MethodColdCodeNode _methodColdCodeNode;
         private DebugLocInfo[] _debugLocInfos;
         private DebugVarInfo[] _debugVarInfos;
         private readonly UnboxingMethodDescFactory _unboxingThunkFactory = new UnboxingMethodDescFactory();