Fold constant offsets and group constant addresses (#2285)

* Fold constant offsets and group constant addresses

* PPTC version bump

ARMeilleure/CodeGen/X86/X86Optimizer.cs

@@ -1,6 +1,7 @@
 using ARMeilleure.CodeGen.Optimizations;
 using ARMeilleure.IntermediateRepresentation;
 using ARMeilleure.Translation;
+using System.Collections.Generic;
 
 using static ARMeilleure.IntermediateRepresentation.OperandHelper;
 using static ARMeilleure.IntermediateRepresentation.OperationHelper;
@@ -11,8 +12,28 @@ namespace ARMeilleure.CodeGen.X86
     {
         public static void RunPass(ControlFlowGraph cfg)
         {
+            var constants = new Dictionary<ulong, Operand>();
+
+            Operand GetConstantCopy(BasicBlock block, Operation operation, Operand source)
+            {
+                if (!constants.TryGetValue(source.Value, out var constant))
+                {
+                    constant = Local(source.Type);
+
+                    Operation copyOp = Operation(Instruction.Copy, constant, source);
+
+                    block.Operations.AddBefore(operation, copyOp);
+
+                    constants.Add(source.Value, constant);
+                }
+
+                return constant;
+            }
+
             for (BasicBlock block = cfg.Blocks.First; block != null; block = block.ListNext)
             {
+                constants.Clear();
+
                 Node nextNode;
 
                 for (Node node = block.Operations.First; node != null; node = nextNode)
@@ -33,24 +54,12 @@ namespace ARMeilleure.CodeGen.X86
 
                         if (src1.Kind == OperandKind.Constant && (src1.Relocatable || CodeGenCommon.IsLongConst(src1)))
                         {
-                            Operand temp = Local(src1.Type);
-
-                            Operation copyOp = Operation(Instruction.Copy, temp, src1);
-
-                            block.Operations.AddBefore(operation, copyOp);
-
-                            operation.SetSource(0, temp);
+                            operation.SetSource(0, GetConstantCopy(block, operation, src1));
                         }
 
                         if (src2.Kind == OperandKind.Constant && (src2.Relocatable || CodeGenCommon.IsLongConst(src2)))
                         {
-                            Operand temp = Local(src2.Type);
-
-                            Operation copyOp = Operation(Instruction.Copy, temp, src2);
-
-                            block.Operations.AddBefore(operation, copyOp);
-
-                            operation.SetSource(1, temp);
+                            operation.SetSource(1, GetConstantCopy(block, operation, src2));
                         }
                     }
 
@@ -111,6 +120,11 @@ namespace ARMeilleure.CodeGen.X86
                 return null;
             }
 
+            if (imm == 0 && scale == Multiplier.x1 && indexOp != null)
+            {
+                imm = GetConstOp(ref indexOp);
+            }
+
             return MemoryOp(type, baseOp, indexOp, scale, imm);
         }
 

ARMeilleure/Instructions/InstEmitMemory.cs

@@ -87,8 +87,7 @@ namespace ARMeilleure.Instructions
             }
 
             Operand address = GetAddress(context);
-
-            Operand address2 = context.Add(address, Const(1L << op.Size));
+            Operand address2 = GetAddress(context, 1L << op.Size);
 
             EmitLoad(op.Rt,  address);
             EmitLoad(op.Rt2, address2);
@@ -112,8 +111,7 @@ namespace ARMeilleure.Instructions
             OpCodeMemPair op = (OpCodeMemPair)context.CurrOp;
 
             Operand address = GetAddress(context);
-
-            Operand address2 = context.Add(address, Const(1L << op.Size));
+            Operand address2 = GetAddress(context, 1L << op.Size);
 
             InstEmitMemoryHelper.EmitStore(context, address,  op.Rt,  op.Size);
             InstEmitMemoryHelper.EmitStore(context, address2, op.Rt2, op.Size);
@@ -121,7 +119,7 @@ namespace ARMeilleure.Instructions
             EmitWBackIfNeeded(context, address);
         }
 
-        private static Operand GetAddress(ArmEmitterContext context)
+        private static Operand GetAddress(ArmEmitterContext context, long addend = 0)
         {
             Operand address = null;
 
@@ -134,7 +132,11 @@ namespace ARMeilleure.Instructions
                     // Pre-indexing.
                     if (!op.PostIdx)
                     {
-                        address = context.Add(address, Const(op.Immediate));
+                        address = context.Add(address, Const(op.Immediate + addend));
+                    }
+                    else if (addend != 0)
+                    {
+                        address = context.Add(address, Const(addend));
                     }
 
                     break;
@@ -153,6 +155,11 @@ namespace ARMeilleure.Instructions
 
                     address = context.Add(n, m);
 
+                    if (addend != 0)
+                    {
+                        address = context.Add(address, Const(addend));
+                    }
+
                     break;
                 }
             }

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 = 1866; //! To be incremented manually for each change to the ARMeilleure project.
+        private const uint InternalVersion = 2285; //! To be incremented manually for each change to the ARMeilleure project.
 
         private const string ActualDir = "0";
         private const string BackupDir = "1";