"Namespace" all the local strings

Since all the files are generated from separate tasks, we don't have a global LLVM IR state which
can keep track of strings and ensure that there are no duplicate symbol names.  To prevent potential
clashes, each generator now sets the default string group name which is unique for each module.

In the future, we should try to manage strings globally (which would also result in more de-duplication)

Author: grendello

src/Xamarin.Android.Build.Tasks/Utilities/ApplicationConfigNativeAssemblyGenerator.cs

@@ -203,6 +203,8 @@ public ApplicationConfigNativeAssemblyGenerator (IDictionary<string, string> env
 
 		protected override void Construct (LlvmIrModule module)
 		{
+			module.DefaultStringGroup = "env";
+
 			MapStructures (module);
 
 			module.AddGlobalVariable ("format_tag", FORMAT_TAG, comment: $" 0x{FORMAT_TAG:x}");
@@ -211,7 +213,7 @@ protected override void Construct (LlvmIrModule module)
 			var envVars = new LlvmIrGlobalVariable (environmentVariables, "app_environment_variables") {
 				Comment = " Application environment variables array, name:value",
 			};
-			module.Add (envVars, stringGroupName: "env", stringGroupComment: " Application environment variables name:value pairs");
+			module.Add (envVars, stringGroupName: "env.var", stringGroupComment: " Application environment variables name:value pairs");
 
 			var sysProps = new LlvmIrGlobalVariable (systemProperties, "app_system_properties") {
 				Comment = " System properties defined by the application",

src/Xamarin.Android.Build.Tasks/Utilities/CompressedAssembliesNativeAssemblyGenerator.cs

@@ -149,6 +149,8 @@ void InitCompressedAssemblies (out List<LlvmIrGlobalVariable>? compressedAssembl
 
 		protected override void Construct (LlvmIrModule module)
 		{
+			module.DefaultStringGroup = "cas";
+
 			MapStructures (module);
 
 			InitCompressedAssemblies (

src/Xamarin.Android.Build.Tasks/Utilities/JniRemappingAssemblyGenerator.cs

@@ -284,6 +284,8 @@ uint GetLength (string str)
 
 		protected override void Construct (LlvmIrModule module)
 		{
+			module.DefaultStringGroup = "jremap";
+
 			MapStructures (module);
 			List<StructureInstance<JniRemappingTypeReplacementEntry>>? typeReplacements;
 			List<StructureInstance<JniRemappingIndexTypeEntry>>? methodIndexTypes;

src/Xamarin.Android.Build.Tasks/Utilities/LlvmIrGenerator/LlvmIrModule.cs

@@ -49,6 +49,8 @@ partial class LlvmIrModule
 
 		public readonly LlvmIrTypeCache TypeCache;
 
+		public string? DefaultStringGroup { get; set; }
+
 		public LlvmIrModule (LlvmIrTypeCache cache, TaskLoggingHelper log)
 		{
 			this.log = log;
@@ -405,7 +407,7 @@ void AddStandardGlobalVariable (LlvmIrGlobalVariable variable)
 		void EnsureStringManager ()
 		{
 			if (stringManager == null) {
-				stringManager = new LlvmIrStringManager (log);
+				stringManager = new LlvmIrStringManager (log, DefaultStringGroup);
 			}
 		}
 

src/Xamarin.Android.Build.Tasks/Utilities/LlvmIrGenerator/LlvmIrStringManager.cs

@@ -9,6 +9,8 @@ partial class LlvmIrModule
 {
 	protected class LlvmIrStringManager
 	{
+		readonly string defaultGroupName = "str";
+
 		Dictionary<StringHolder, LlvmIrStringVariable> stringSymbolCache = new Dictionary<StringHolder, LlvmIrStringVariable> ();
 		Dictionary<string, LlvmIrStringGroup> stringGroupCache = new Dictionary<string, LlvmIrStringGroup> (StringComparer.Ordinal);
 		List<LlvmIrStringGroup> stringGroups = new List<LlvmIrStringGroup> ();
@@ -18,9 +20,13 @@ protected class LlvmIrStringManager
 
 		public List<LlvmIrStringGroup> StringGroups => stringGroups;
 
-		public LlvmIrStringManager (TaskLoggingHelper log)
+		public LlvmIrStringManager (TaskLoggingHelper log, string? defaultStringGroup = null)
 		{
 			this.log = log;
+			if (!String.IsNullOrEmpty (defaultStringGroup)) {
+				defaultGroupName = defaultStringGroup;
+			}
+
 			defaultGroup = new LlvmIrStringGroup ();
 			stringGroupCache.Add (String.Empty, defaultGroup);
 			stringGroups.Add (defaultGroup);
@@ -52,7 +58,7 @@ LlvmIrStringVariable Add (StringHolder holder, string? groupName = null, string?
 			string groupPrefix;
 			if (String.IsNullOrEmpty (groupName) || String.Compare ("str", groupName, StringComparison.Ordinal) == 0) {
 				group = defaultGroup;
-				groupPrefix = ".str";
+				groupPrefix = $".{defaultGroupName}";
 			} else if (!stringGroupCache.TryGetValue (groupName, out group) || group == null) {
 				group = new LlvmIrStringGroup (groupComment ?? groupName);
 				stringGroups.Add (group);

src/Xamarin.Android.Build.Tasks/Utilities/LlvmIrGenerator/LlvmIrVariable.cs

@@ -301,8 +301,8 @@ class LlvmIrStringVariable : LlvmIrGlobalVariable
 	public string IrType { get; }
 	public bool IsConstantStringLiteral { get; }
 
-	public LlvmIrStringVariable (string name, StringHolder value)
-		: base (typeof(string), name, LlvmIrVariableOptions.LocalString)
+	public LlvmIrStringVariable (string name, StringHolder value, LlvmIrVariableOptions? options = null)
+		: base (typeof(string), name, options ?? LlvmIrVariableOptions.GlobalConstexprString)
 	{
 		Value = value;
 		Encoding = value.Encoding;
@@ -322,8 +322,8 @@ public LlvmIrStringVariable (string name, StringHolder value)
 		}
 	}
 
-	public LlvmIrStringVariable (string name, string value, LlvmIrStringEncoding encoding, StringComparison comparison = StringComparison.Ordinal)
-		: this (name, new StringHolder (value, encoding, comparison))
+	public LlvmIrStringVariable (string name, string value, LlvmIrStringEncoding encoding, StringComparison comparison = StringComparison.Ordinal, LlvmIrVariableOptions? options = null)
+		: this (name, new StringHolder (value, encoding, comparison), options)
 	{}
 }
 

src/Xamarin.Android.Build.Tasks/Utilities/MarshalMethodsNativeAssemblyGenerator.cs

@@ -592,6 +592,8 @@ void AddParameter (Type type)
 
 		protected override void Construct (LlvmIrModule module)
 		{
+			module.DefaultStringGroup = "mm";
+
 			MapStructures (module);
 
 			Init ();

src/Xamarin.Android.Build.Tasks/Utilities/TypeMappingDebugNativeAssemblyGenerator.cs

@@ -129,6 +129,8 @@ public TypeMappingDebugNativeAssemblyGenerator (TaskLoggingHelper log, TypeMapGe
 
 		protected override void Construct (LlvmIrModule module)
 		{
+			module.DefaultStringGroup = "tmd";
+
 			MapStructures (module);
 
 			if (data.ManagedToJavaMap != null && data.ManagedToJavaMap.Count > 0) {

src/Xamarin.Android.Build.Tasks/Utilities/TypeMappingReleaseNativeAssemblyGenerator.cs

@@ -189,6 +189,8 @@ public TypeMappingReleaseNativeAssemblyGenerator (TaskLoggingHelper log, NativeT
 
 		protected override void Construct (LlvmIrModule module)
 		{
+			module.DefaultStringGroup = "tmr";
+
 			MapStructures (module);
 
 			var cs = new ConstructionState ();