1 files changed, 327 insertions, 0 deletions
diff --git a/ARMeilleure/CodeGen/X86/PreAllocatorWindows.cs b/ARMeilleure/CodeGen/X86/PreAllocatorWindows.cs
new file mode 100644
index 00000000..45319e6a
--- /dev/null
+++ b/ARMeilleure/CodeGen/X86/PreAllocatorWindows.cs
@@ -0,0 +1,327 @@
+using ARMeilleure.CodeGen.RegisterAllocators;
+using ARMeilleure.IntermediateRepresentation;
+using ARMeilleure.Translation;
+using System;
+using System.Diagnostics;
+using static ARMeilleure.IntermediateRepresentation.Operand.Factory;
+using static ARMeilleure.IntermediateRepresentation.Operation.Factory;
+
+namespace ARMeilleure.CodeGen.X86
+{
+    class PreAllocatorWindows : PreAllocator
+    {
+        public static void InsertCallCopies(IntrusiveList<Operation> nodes, StackAllocator stackAlloc, Operation node)
+        {
+            Operand dest = node.Destination;
+
+            // Handle struct arguments.
+            int retArgs = 0;
+            int stackAllocOffset = 0;
+
+            int AllocateOnStack(int size)
+            {
+                // We assume that the stack allocator is initially empty (TotalSize = 0).
+                // Taking that into account, we can reuse the space allocated for other
+                // calls by keeping track of our own allocated size (stackAllocOffset).
+                // If the space allocated is not big enough, then we just expand it.
+                int offset = stackAllocOffset;
+
+                if (stackAllocOffset + size > stackAlloc.TotalSize)
+                {
+                    stackAlloc.Allocate((stackAllocOffset + size) - stackAlloc.TotalSize);
+                }
+
+                stackAllocOffset += size;
+
+                return offset;
+            }
+
+            Operand arg0Reg = default;
+
+            if (dest != default && dest.Type == OperandType.V128)
+            {
+                int stackOffset = AllocateOnStack(dest.Type.GetSizeInBytes());
+
+                arg0Reg = Gpr(CallingConvention.GetIntArgumentRegister(0), OperandType.I64);
+
+                Operation allocOp = Operation(Instruction.StackAlloc, arg0Reg, Const(stackOffset));
+
+                nodes.AddBefore(node, allocOp);
+
+                retArgs = 1;
+            }
+
+            int argsCount = node.SourcesCount - 1;
+            int maxArgs = CallingConvention.GetArgumentsOnRegsCount() - retArgs;
+
+            if (argsCount > maxArgs)
+            {
+                argsCount = maxArgs;
+            }
+
+            Operand[] sources = new Operand[1 + retArgs + argsCount];
+
+            sources[0] = node.GetSource(0);
+
+            if (arg0Reg != default)
+            {
+                sources[1] = arg0Reg;
+            }
+
+            for (int index = 1; index < node.SourcesCount; index++)
+            {
+                Operand source = node.GetSource(index);
+
+                if (source.Type == OperandType.V128)
+                {
+                    Operand stackAddr = Local(OperandType.I64);
+
+                    int stackOffset = AllocateOnStack(source.Type.GetSizeInBytes());
+
+                    nodes.AddBefore(node, Operation(Instruction.StackAlloc, stackAddr, Const(stackOffset)));
+
+                    Operation storeOp = Operation(Instruction.Store, default, stackAddr, source);
+
+                    InsertConstantRegCopies(nodes, nodes.AddBefore(node, storeOp));
+
+                    node.SetSource(index, stackAddr);
+                }
+            }
+
+            // Handle arguments passed on registers.
+            for (int index = 0; index < argsCount; index++)
+            {
+                Operand source = node.GetSource(index + 1);
+                Operand argReg;
+
+                int argIndex = index + retArgs;
+
+                if (source.Type.IsInteger())
+                {
+                    argReg = Gpr(CallingConvention.GetIntArgumentRegister(argIndex), source.Type);
+                }
+                else
+                {
+                    argReg = Xmm(CallingConvention.GetVecArgumentRegister(argIndex), source.Type);
+                }
+
+                Operation copyOp = Operation(Instruction.Copy, argReg, source);
+
+                InsertConstantRegCopies(nodes, nodes.AddBefore(node, copyOp));
+
+                sources[1 + retArgs + index] = argReg;
+            }
+
+            // The remaining arguments (those that are not passed on registers)
+            // should be passed on the stack, we write them to the stack with "SpillArg".
+            for (int index = argsCount; index < node.SourcesCount - 1; index++)
+            {
+                Operand source = node.GetSource(index + 1);
+                Operand offset = Const((index + retArgs) * 8);
+
+                Operation spillOp = Operation(Instruction.SpillArg, default, offset, source);
+
+                InsertConstantRegCopies(nodes, nodes.AddBefore(node, spillOp));
+            }
+
+            if (dest != default)
+            {
+                if (dest.Type == OperandType.V128)
+                {
+                    Operand retValueAddr = Local(OperandType.I64);
+
+                    nodes.AddBefore(node, Operation(Instruction.Copy, retValueAddr, arg0Reg));
+
+                    Operation loadOp = Operation(Instruction.Load, dest, retValueAddr);
+
+                    nodes.AddAfter(node, loadOp);
+
+                    node.Destination = default;
+                }
+                else
+                {
+                    Operand retReg = dest.Type.IsInteger()
+                        ? Gpr(CallingConvention.GetIntReturnRegister(), dest.Type)
+                        : Xmm(CallingConvention.GetVecReturnRegister(), dest.Type);
+
+                    Operation copyOp = Operation(Instruction.Copy, dest, retReg);
+
+                    nodes.AddAfter(node, copyOp);
+
+                    node.Destination = retReg;
+                }
+            }
+
+            node.SetSources(sources);
+        }
+
+        public static void InsertTailcallCopies(IntrusiveList<Operation> nodes, StackAllocator stackAlloc, Operation node)
+        {
+            int argsCount = node.SourcesCount - 1;
+            int maxArgs = CallingConvention.GetArgumentsOnRegsCount();
+
+            if (argsCount > maxArgs)
+            {
+                throw new NotImplementedException("Spilling is not currently supported for tail calls. (too many arguments)");
+            }
+
+            Operand[] sources = new Operand[1 + argsCount];
+
+            // Handle arguments passed on registers.
+            for (int index = 0; index < argsCount; index++)
+            {
+                Operand source = node.GetSource(1 + index);
+                Operand argReg = source.Type.IsInteger()
+                    ? Gpr(CallingConvention.GetIntArgumentRegister(index), source.Type)
+                    : Xmm(CallingConvention.GetVecArgumentRegister(index), source.Type);
+
+                Operation copyOp = Operation(Instruction.Copy, argReg, source);
+
+                InsertConstantRegCopies(nodes, nodes.AddBefore(node, copyOp));
+
+                sources[1 + index] = argReg;
+            }
+
+            // The target address must be on the return registers, since we
+            // don't return anything and it is guaranteed to not be a
+            // callee saved register (which would be trashed on the epilogue).
+            Operand retReg = Gpr(CallingConvention.GetIntReturnRegister(), OperandType.I64);
+
+            Operation addrCopyOp = Operation(Instruction.Copy, retReg, node.GetSource(0));
+
+            nodes.AddBefore(node, addrCopyOp);
+
+            sources[0] = retReg;
+
+            node.SetSources(sources);
+        }
+
+        public static Operation InsertLoadArgumentCopy(
+            CompilerContext cctx,
+            ref Span<Operation> buffer,
+            IntrusiveList<Operation> nodes,
+            Operand[] preservedArgs,
+            Operation node)
+        {
+            Operand source = node.GetSource(0);
+
+            Debug.Assert(source.Kind == OperandKind.Constant, "Non-constant LoadArgument source kind.");
+
+            int retArgs = cctx.FuncReturnType == OperandType.V128 ? 1 : 0;
+
+            int index = source.AsInt32() + retArgs;
+
+            if (index < CallingConvention.GetArgumentsOnRegsCount())
+            {
+                Operand dest = node.Destination;
+
+                if (preservedArgs[index] == default)
+                {
+                    Operand argReg, pArg;
+
+                    if (dest.Type.IsInteger())
+                    {
+                        argReg = Gpr(CallingConvention.GetIntArgumentRegister(index), dest.Type);
+                        pArg = Local(dest.Type);
+                    }
+                    else if (dest.Type == OperandType.V128)
+                    {
+                        argReg = Gpr(CallingConvention.GetIntArgumentRegister(index), OperandType.I64);
+                        pArg = Local(OperandType.I64);
+                    }
+                    else
+                    {
+                        argReg = Xmm(CallingConvention.GetVecArgumentRegister(index), dest.Type);
+                        pArg = Local(dest.Type);
+                    }
+
+                    Operation copyOp = Operation(Instruction.Copy, pArg, argReg);
+
+                    cctx.Cfg.Entry.Operations.AddFirst(copyOp);
+
+                    preservedArgs[index] = pArg;
+                }
+
+                Operation nextNode;
+
+                if (dest.Type != OperandType.V128 && dest.AssignmentsCount == 1)
+                {
+                    // Let's propagate the argument if we can to avoid copies.
+                    PreAllocatorCommon.Propagate(ref buffer, dest, preservedArgs[index]);
+                    nextNode = node.ListNext;
+                }
+                else
+                {
+                    Operation argCopyOp = Operation(dest.Type == OperandType.V128
+                        ? Instruction.Load
+                        : Instruction.Copy, dest, preservedArgs[index]);
+
+                    nextNode = nodes.AddBefore(node, argCopyOp);
+                }
+
+                Delete(nodes, node);
+                return nextNode;
+            }
+            else
+            {
+                // TODO: Pass on stack.
+                return node;
+            }
+        }
+
+        public static void InsertReturnCopy(
+            CompilerContext cctx,
+            IntrusiveList<Operation> nodes,
+            Operand[] preservedArgs,
+            Operation node)
+        {
+            if (node.SourcesCount == 0)
+            {
+                return;
+            }
+
+            Operand source = node.GetSource(0);
+            Operand retReg;
+
+            if (source.Type.IsInteger())
+            {
+                retReg = Gpr(CallingConvention.GetIntReturnRegister(), source.Type);
+            }
+            else if (source.Type == OperandType.V128)
+            {
+                if (preservedArgs[0] == default)
+                {
+                    Operand preservedArg = Local(OperandType.I64);
+                    Operand arg0 = Gpr(CallingConvention.GetIntArgumentRegister(0), OperandType.I64);
+
+                    Operation copyOp = Operation(Instruction.Copy, preservedArg, arg0);
+
+                    cctx.Cfg.Entry.Operations.AddFirst(copyOp);
+
+                    preservedArgs[0] = preservedArg;
+                }
+
+                retReg = preservedArgs[0];
+            }
+            else
+            {
+                retReg = Xmm(CallingConvention.GetVecReturnRegister(), source.Type);
+            }
+
+            if (source.Type == OperandType.V128)
+            {
+                Operation retStoreOp = Operation(Instruction.Store, default, retReg, source);
+
+                nodes.AddBefore(node, retStoreOp);
+            }
+            else
+            {
+                Operation retCopyOp = Operation(Instruction.Copy, retReg, source);
+
+                nodes.AddBefore(node, retCopyOp);
+            }
+
+            node.SetSources(Array.Empty<Operand>());
+        }
+    }
+}
+\ No newline at end of file