Rewrite shader decoding stage (#2698)

* Rewrite shader decoding stage

* Fix P2R constant buffer encoding

* Fix PSET/PSETP

* PR feedback

* Log unimplemented shader instructions

* Implement NOP

* Remove using

* PR feedback

Ryujinx.Graphics.Shader/Instructions/InstEmitIntegerMinMax.cs

@@ -0,0 +1,71 @@
+using Ryujinx.Graphics.Shader.Decoders;
+using Ryujinx.Graphics.Shader.IntermediateRepresentation;
+using Ryujinx.Graphics.Shader.Translation;
+
+using static Ryujinx.Graphics.Shader.Instructions.InstEmitAluHelper;
+using static Ryujinx.Graphics.Shader.Instructions.InstEmitHelper;
+
+namespace Ryujinx.Graphics.Shader.Instructions
+{
+    static partial class InstEmit
+    {
+        public static void ImnmxR(EmitterContext context)
+        {
+            InstImnmxR op = context.GetOp<InstImnmxR>();
+
+            var srcA = GetSrcReg(context, op.SrcA);
+            var srcB = GetSrcReg(context, op.SrcB);
+            var srcPred = GetPredicate(context, op.SrcPred, op.SrcPredInv);
+
+            EmitImnmx(context, srcA, srcB, srcPred, op.Dest, op.Signed, op.WriteCC);
+        }
+
+        public static void ImnmxI(EmitterContext context)
+        {
+            InstImnmxI op = context.GetOp<InstImnmxI>();
+
+            var srcA = GetSrcReg(context, op.SrcA);
+            var srcB = GetSrcImm(context, Imm20ToSInt(op.Imm20));
+            var srcPred = GetPredicate(context, op.SrcPred, op.SrcPredInv);
+
+            EmitImnmx(context, srcA, srcB, srcPred, op.Dest, op.Signed, op.WriteCC);
+        }
+
+        public static void ImnmxC(EmitterContext context)
+        {
+            InstImnmxC op = context.GetOp<InstImnmxC>();
+
+            var srcA = GetSrcReg(context, op.SrcA);
+            var srcB = GetSrcCbuf(context, op.CbufSlot, op.CbufOffset);
+            var srcPred = GetPredicate(context, op.SrcPred, op.SrcPredInv);
+
+            EmitImnmx(context, srcA, srcB, srcPred, op.Dest, op.Signed, op.WriteCC);
+        }
+
+        private static void EmitImnmx(
+            EmitterContext context,
+            Operand srcA,
+            Operand srcB,
+            Operand srcPred,
+            int rd,
+            bool isSignedInt,
+            bool writeCC)
+        {
+            Operand resMin = isSignedInt
+                ? context.IMinimumS32(srcA, srcB)
+                : context.IMinimumU32(srcA, srcB);
+
+            Operand resMax = isSignedInt
+                ? context.IMaximumS32(srcA, srcB)
+                : context.IMaximumU32(srcA, srcB);
+
+            Operand res = context.ConditionalSelect(srcPred, resMin, resMax);
+
+            context.Copy(GetDest(rd), res);
+
+            SetZnFlags(context, res, writeCC);
+
+            // TODO: X flags.
+        }
+    }
+}