Preparing for precision garbase collection

Source/Data/IR-Instructions.json

@@ -1501,6 +1501,22 @@
 			"IgnoreDuringCodeGeneration": "true",
 			"UnspecifiedSideEffect": "true"
 		},
+		{
+			"Name": "UnstableRegionStart",
+			"FamilyName": "IR",
+			"ResultCount": 0,
+			"OperandCount": 0,
+			"IgnoreDuringCodeGeneration": "true",
+			"UnspecifiedSideEffect": "true"
+		},
+		{
+			"Name": "UnstableRegionEnd",
+			"FamilyName": "IR",
+			"ResultCount": 0,
+			"OperandCount": 0,
+			"IgnoreDuringCodeGeneration": "true",
+			"UnspecifiedSideEffect": "true"
+		},
 		{
 			"Name": "Rethrow",
 			"FamilyName": "IR",

Source/Docs/mosa-runtime-tables.dot

@@ -11,7 +11,7 @@ digraph "MOSA Runtime Tables"
 	];
 
 	"NameString" [
-		label = "<f0>String Object|<f1>Object Header|<f2>Pointer to Method Table|<f3>String Length|<f4>Unicode String"
+		label = "<f0>Internal String Object|<f1>Object Header|<f2>Pointer to Method Table|<f3>String Length|<f4>Unicode String"
 		shape = "record"
 		color = "red"
 	];
@@ -209,7 +209,7 @@ digraph "MOSA Runtime Tables"
 	];
 
 	"MethodDefinition" [
-		label = "<f0>Method Definition|<f1>Pointer to Method Name|<f2>~Pointer to Custom Attributes|<f3>Method Attributes|<f4>Local & Parameter Stack Size|<f5>Pointer to Method|<f6>Pointer to Return Type Definition|<f7>~Pointer to Protected Region Table|<f8>Pointer to SafePoint Table|<f9>Number of Parameters|<f10>Pointer to Parameter Definition 1|...|Pointer to Parameter Definition N"
+		label = "<f0>Method Definition|<f1>Pointer to Method Name|<f2>~Pointer to Custom Attributes|<f3>Method Attributes|<f4>Local & Parameter Stack Size|<f5>Pointer to Method|<f6>Pointer to Return Type Definition|<f7>~Pointer to Protected Region Table|<f8>Pointer to Method GC Data|<f9>Number of Parameters|<f10>Pointer to Parameter Definition 1|...|Pointer to Parameter Definition N"
 		shape = "record"
 		color = "purple"
 	];
@@ -232,7 +232,7 @@ digraph "MOSA Runtime Tables"
 		color = "blue"
 	];
 
-	"MethodDefinition":f8 -> "SafePointTable":f0 [
+	"MethodDefinition":f8 -> "Method GC Data":f0 [
 		id = 0
 	];
 
@@ -258,14 +258,24 @@ digraph "MOSA Runtime Tables"
 		id = 0
 		color = "blue"
 	];
+
+	"Method GC Data" [
+		label = "<f0>Method GC Data|<f1>Pointer to SafePoint Table|<f2>Pointer to Method GC Stack Data"
+		shape = "record"
+	];
+
+	"Method GC Data":f1 -> "SafePoint":f0 [
+		id = 0
+		style = "dotted"
+	];
 
 	"SafePointTable" [
 		label = "<f0>SafePoint Table|<f1>Number of SafePoints|<f2>SafePoint 1|..|SafePoint N"
 		shape = "record"
 	];
 
 	"SafePoint" [
-		label = "<f0>SafePoint|<f1>Address Offset|<f2>Address Range (signed)|<f3>Breakpoint Indicator|<f4>CPU Registers Bitmap (64 bit)"
+		label = "<f0>SafePoint|<f1>Address Offset|<f2>Address Range (signed)|<f3>Breakpoint Indicator|<f4>CPU Registers Bitmap (32 bit)"
 		shape = "record"
 	];
 

Source/Docs/runtime-tables.rst

@@ -5,3 +5,15 @@ MOSA Runtime Tables
 This diagram represents the internal runtime tables within the MOSA virtual machine:
 
 .. graphviz:: mosa-runtime-tables.dot
+
+Internal String Object
+----------------------
+
+.. csv-table::
+   :header: "Fields"
+   :widths: 200
+
+	Object Header
+	Pointer to Method Table
+	String Length
+	Unicode String

Source/Mosa.Compiler.Framework/IR.cs

@@ -225,6 +225,8 @@ public static class IR
 	public static readonly BaseInstruction TryEnd = new TryEnd();
 	public static readonly BaseInstruction TryStart = new TryStart();
 	public static readonly BaseInstruction SafePoint = new SafePoint();
+	public static readonly BaseInstruction UnstableRegionStart = new UnstableRegionStart();
+	public static readonly BaseInstruction UnstableRegionEnd = new UnstableRegionEnd();
 	public static readonly BaseInstruction Rethrow = new Rethrow();
 	public static readonly BaseInstruction GetVirtualFunctionPtr = new GetVirtualFunctionPtr();
 	public static readonly BaseInstruction MemoryCopy = new MemoryCopy();

Source/Mosa.Compiler.Framework/Instructions/UnstableRegionEnd.cs

@@ -0,0 +1,18 @@
+// Copyright (c) MOSA Project. Licensed under the New BSD License.
+
+// This code was generated by an automated template.
+
+namespace Mosa.Compiler.Framework.Instructions;
+
+/// <summary>
+/// UnstableRegionEnd
+/// </summary>
+public sealed class UnstableRegionEnd : BaseIRInstruction
+{
+	public UnstableRegionEnd()
+		: base(0, 0)
+	{
+	}
+
+	public override bool IgnoreDuringCodeGeneration => true;
+}

Source/Mosa.Compiler.Framework/Instructions/UnstableRegionStart.cs

@@ -0,0 +1,18 @@
+// Copyright (c) MOSA Project. Licensed under the New BSD License.
+
+// This code was generated by an automated template.
+
+namespace Mosa.Compiler.Framework.Instructions;
+
+/// <summary>
+/// UnstableRegionStart
+/// </summary>
+public sealed class UnstableRegionStart : BaseIRInstruction
+{
+	public UnstableRegionStart()
+		: base(0, 0)
+	{
+	}
+
+	public override bool IgnoreDuringCodeGeneration => true;
+}

Source/Mosa.Compiler.Framework/Stages/SafePointStage.cs

@@ -6,7 +6,7 @@ namespace Mosa.Compiler.Framework.Stages;
 
 // TODO:
 // 1. Analyze method and determine:
-//    A. Determine if method contain any refernces to objects, or have any managed pointers
+//    A. Determine if method contains any references to objects, or have any managed pointers
 //    B. Determine start/end ranges of objects and managed pointers on the local stack and parameters
 //    C. Place SafePoint at:
 //       i.  Method prologue

Source/Mosa.Compiler.Framework/Transforms/Compound/BaseCompoundTransform.cs

@@ -26,7 +26,9 @@ protected static void CopyCompound(Transform transform, Context context, Operand
 		var srcReg = transform.VirtualRegisters.AllocateNativeInteger();
 		var dstReg = transform.VirtualRegisters.AllocateNativeInteger();
 
-		context.SetInstruction(transform.AddInstruction, srcReg, sourceBase, source);
+		context.SetInstruction(IR.UnstableRegionStart);
+
+		context.AppendInstruction(transform.AddInstruction, srcReg, sourceBase, source);
 		context.AppendInstruction(transform.AddInstruction, dstReg, destinationBase, destination);
 
 		var tmp = transform.VirtualRegisters.AllocateNativeInteger();
@@ -70,6 +72,8 @@ protected static void CopyCompound(Transform transform, Context context, Operand
 				continue;
 			}
 		}
+
+		context.AppendInstruction(IR.UnstableRegionEnd);
 	}
 
 	#endregion Helpers