Use branch instead of tailcall for recursive calls (#2282)

* Use branch instead of tailcall for recursive calls

Use a branch instead of doing a tailcall for recursive calls. This
avoids having to store the dispatch address, setting up the epilogue and
keeps guest registers in host registers for longer.

The rejit check is moved down into the entry block so that the rejit
behaviour remains the same as before.

* Set PTC version

Co-authored-by: gdkchan <gab.dark.100@gmail.com>

ARMeilleure/Instructions/InstEmitFlowHelper.cs

@@ -144,7 +144,14 @@ namespace ARMeilleure.Instructions
         {
             bool isRecursive = immediate == context.EntryAddress;
 
-            EmitJumpTableBranch(context, Const(immediate), isRecursive);
+            if (isRecursive)
+            {
+                context.Branch(context.GetLabel(immediate));
+            }
+            else
+            {
+                EmitJumpTableBranch(context, Const(immediate), isJump: false);
+            }
         }
 
         private static void EmitNativeCall(ArmEmitterContext context, Operand nativeContextPtr, Operand funcAddr, bool isJump)

ARMeilleure/Translation/PTC/Ptc.cs

@@ -28,7 +28,7 @@ namespace ARMeilleure.Translation.PTC
         private const string OuterHeaderMagicString = "PTCohd\0\0";
         private const string InnerHeaderMagicString = "PTCihd\0\0";
 
-        private const uint InternalVersion = 2279; //! To be incremented manually for each change to the ARMeilleure project.
+        private const uint InternalVersion = 2282; //! To be incremented manually for each change to the ARMeilleure project.
 
         private const string ActualDir = "0";
         private const string BackupDir = "1";

ARMeilleure/Translation/Translator.cs

@@ -237,13 +237,6 @@ namespace ARMeilleure.Translation
 
             Logger.StartPass(PassName.Translation);
 
-            Counter<uint> counter = null;
-
-            if (!context.HighCq)
-            {
-                EmitRejitCheck(context, out counter);
-            }
-
             EmitSynchronization(context);
 
             if (blocks[0].Address != address)
@@ -251,7 +244,7 @@ namespace ARMeilleure.Translation
                 context.Branch(context.GetLabel(address));
             }
 
-            ControlFlowGraph cfg = EmitAndGetCFG(context, blocks, out Range funcRange);
+            ControlFlowGraph cfg = EmitAndGetCFG(context, blocks, out Range funcRange, out Counter<uint> counter);
 
             ulong funcSize = funcRange.End - funcRange.Start;
 
@@ -322,8 +315,14 @@ namespace ARMeilleure.Translation
             }
         }
 
-        private static ControlFlowGraph EmitAndGetCFG(ArmEmitterContext context, Block[] blocks, out Range range)
+        private static ControlFlowGraph EmitAndGetCFG(
+            ArmEmitterContext context,
+            Block[] blocks,
+            out Range range,
+            out Counter<uint> counter)
         {
+            counter = null;
+
             ulong rangeStart = ulong.MaxValue;
             ulong rangeEnd = 0;
 
@@ -344,6 +343,11 @@ namespace ARMeilleure.Translation
                     }
                 }
 
+                if (block.Address == context.EntryAddress && !context.HighCq)
+                {
+                    EmitRejitCheck(context, out counter);
+                }
+
                 context.CurrBlock = block;
 
                 context.MarkLabel(context.GetLabel(block.Address));