1 files changed, 196 insertions, 0 deletions
diff --git a/ARMeilleure/Instructions/InstEmitBfm.cs b/ARMeilleure/Instructions/InstEmitBfm.cs
new file mode 100644
index 00000000..8fdbf6cf
--- /dev/null
+++ b/ARMeilleure/Instructions/InstEmitBfm.cs
@@ -0,0 +1,196 @@
+using ARMeilleure.Decoders;
+using ARMeilleure.IntermediateRepresentation;
+using ARMeilleure.Translation;
+
+using static ARMeilleure.Instructions.InstEmitHelper;
+using static ARMeilleure.IntermediateRepresentation.OperandHelper;
+
+namespace ARMeilleure.Instructions
+{
+    static partial class InstEmit
+    {
+        public static void Bfm(ArmEmitterContext context)
+        {
+            OpCodeBfm op = (OpCodeBfm)context.CurrOp;
+
+            Operand d = GetIntOrZR(context, op.Rd);
+            Operand n = GetIntOrZR(context, op.Rn);
+
+            Operand res;
+
+            if (op.Pos < op.Shift)
+            {
+                // BFI.
+                int shift = op.GetBitsCount() - op.Shift;
+
+                int width = op.Pos + 1;
+
+                long mask = (long)(ulong.MaxValue >> (64 - width));
+
+                res = context.ShiftLeft(context.BitwiseAnd(n, Const(n.Type, mask)), Const(shift));
+
+                res = context.BitwiseOr(res, context.BitwiseAnd(d, Const(d.Type, ~(mask << shift))));
+            }
+            else
+            {
+                // BFXIL.
+                int shift = op.Shift;
+
+                int width = op.Pos - shift + 1;
+
+                long mask = (long)(ulong.MaxValue >> (64 - width));
+
+                res = context.BitwiseAnd(context.ShiftRightUI(n, Const(shift)), Const(n.Type, mask));
+
+                res = context.BitwiseOr(res, context.BitwiseAnd(d, Const(d.Type, ~mask)));
+            }
+
+            SetIntOrZR(context, op.Rd, res);
+        }
+
+        public static void Sbfm(ArmEmitterContext context)
+        {
+            OpCodeBfm op = (OpCodeBfm)context.CurrOp;
+
+            int bitsCount = op.GetBitsCount();
+
+            if (op.Pos + 1 == bitsCount)
+            {
+                EmitSbfmShift(context);
+            }
+            else if (op.Pos < op.Shift)
+            {
+                EmitSbfiz(context);
+            }
+            else if (op.Pos == 7 && op.Shift == 0)
+            {
+                Operand n = GetIntOrZR(context, op.Rn);
+
+                SetIntOrZR(context, op.Rd, context.SignExtend8(n.Type, n));
+            }
+            else if (op.Pos == 15 && op.Shift == 0)
+            {
+                Operand n = GetIntOrZR(context, op.Rn);
+
+                SetIntOrZR(context, op.Rd, context.SignExtend16(n.Type, n));
+            }
+            else if (op.Pos == 31 && op.Shift == 0)
+            {
+                Operand n = GetIntOrZR(context, op.Rn);
+
+                SetIntOrZR(context, op.Rd, context.SignExtend32(n.Type, n));
+            }
+            else
+            {
+                Operand res = GetIntOrZR(context, op.Rn);
+
+                res = context.ShiftLeft   (res, Const(bitsCount - 1 - op.Pos));
+                res = context.ShiftRightSI(res, Const(bitsCount - 1));
+                res = context.BitwiseAnd  (res, Const(res.Type, ~op.TMask));
+
+                Operand n2 = GetBfmN(context);
+
+                SetIntOrZR(context, op.Rd, context.BitwiseOr(res, n2));
+            }
+        }
+
+        public static void Ubfm(ArmEmitterContext context)
+        {
+            OpCodeBfm op = (OpCodeBfm)context.CurrOp;
+
+            if (op.Pos + 1 == op.GetBitsCount())
+            {
+                EmitUbfmShift(context);
+            }
+            else if (op.Pos < op.Shift)
+            {
+                EmitUbfiz(context);
+            }
+            else if (op.Pos + 1 == op.Shift)
+            {
+                EmitBfmLsl(context);
+            }
+            else if (op.Pos == 7 && op.Shift == 0)
+            {
+                Operand n = GetIntOrZR(context, op.Rn);
+
+                SetIntOrZR(context, op.Rd, context.BitwiseAnd(n, Const(n.Type, 0xff)));
+            }
+            else if (op.Pos == 15 && op.Shift == 0)
+            {
+                Operand n = GetIntOrZR(context, op.Rn);
+
+                SetIntOrZR(context, op.Rd, context.BitwiseAnd(n, Const(n.Type, 0xffff)));
+            }
+            else
+            {
+                SetIntOrZR(context, op.Rd, GetBfmN(context));
+            }
+        }
+
+        private static void EmitSbfiz(ArmEmitterContext context) => EmitBfiz(context, signed: true);
+        private static void EmitUbfiz(ArmEmitterContext context) => EmitBfiz(context, signed: false);
+
+        private static void EmitBfiz(ArmEmitterContext context, bool signed)
+        {
+            OpCodeBfm op = (OpCodeBfm)context.CurrOp;
+
+            int width = op.Pos + 1;
+
+            Operand res = GetIntOrZR(context, op.Rn);
+
+            res = context.ShiftLeft(res, Const(op.GetBitsCount() - width));
+
+            res = signed
+                ? context.ShiftRightSI(res, Const(op.Shift - width))
+                : context.ShiftRightUI(res, Const(op.Shift - width));
+
+            SetIntOrZR(context, op.Rd, res);
+        }
+
+        private static void EmitSbfmShift(ArmEmitterContext context)
+        {
+            EmitBfmShift(context, signed: true);
+        }
+
+        private static void EmitUbfmShift(ArmEmitterContext context)
+        {
+            EmitBfmShift(context, signed: false);
+        }
+
+        private static void EmitBfmShift(ArmEmitterContext context, bool signed)
+        {
+            OpCodeBfm op = (OpCodeBfm)context.CurrOp;
+
+            Operand res = GetIntOrZR(context, op.Rn);
+
+            res = signed
+                ? context.ShiftRightSI(res, Const(op.Shift))
+                : context.ShiftRightUI(res, Const(op.Shift));
+
+            SetIntOrZR(context, op.Rd, res);
+        }
+
+        private static void EmitBfmLsl(ArmEmitterContext context)
+        {
+            OpCodeBfm op = (OpCodeBfm)context.CurrOp;
+
+            Operand res = GetIntOrZR(context, op.Rn);
+
+            int shift = op.GetBitsCount() - op.Shift;
+
+            SetIntOrZR(context, op.Rd, context.ShiftLeft(res, Const(shift)));
+        }
+
+        private static Operand GetBfmN(ArmEmitterContext context)
+        {
+            OpCodeBfm op = (OpCodeBfm)context.CurrOp;
+
+            Operand res = GetIntOrZR(context, op.Rn);
+
+            long mask = op.WMask & op.TMask;
+
+            return context.BitwiseAnd(context.RotateRight(res, Const(op.Shift)), Const(res.Type, mask));
+        }
+    }
+}
+\ No newline at end of file