New shader translator implementation (#654)

* Start implementing a new shader translator

* Fix shift instructions and a typo

* Small refactoring on StructuredProgram, move RemovePhis method to a separate class

* Initial geometry shader support

* Implement TLD4

* Fix -- There's no negation on FMUL32I

* Add constant folding and algebraic simplification optimizations, nits

* Some leftovers from constant folding

* Avoid cast for constant assignments

* Add a branch elimination pass, and misc small fixes

* Remove redundant branches, add expression propagation and other improvements on the code

* Small leftovers -- add missing break and continue, remove unused properties, other improvements

* Add null check to handle empty block cases on block visitor

* Add HADD2 and HMUL2 half float shader instructions

* Optimize pack/unpack sequences, some fixes related to half float instructions

* Add TXQ, TLD, TLDS and TLD4S shader texture instructions, and some support for bindless textures, some refactoring on codegen

* Fix copy paste mistake that caused RZ to be ignored on the AST instruction

* Add workaround for conditional exit, and fix half float instruction with constant buffer

* Add missing 0.0 source for TLDS.LZ variants

* Simplify the switch for TLDS.LZ

* Texture instructions related fixes

* Implement the HFMA instruction, and some misc. fixes

* Enable constant folding on UnpackHalf2x16 instructions

* Refactor HFMA to use OpCode* for opcode decoding rather than on the helper methods

* Remove the old shader translator

* Remove ShaderDeclInfo and other unused things

* Add dual vertex shader support

* Add ShaderConfig, used to pass shader type and maximum cbuffer size

* Move and rename some instruction enums

* Move texture instructions into a separate file

* Move operand GetExpression and locals management to OperandManager

* Optimize opcode decoding using a simple list and binary search

* Add missing condition for do-while on goto elimination

* Misc. fixes on texture instructions

* Simplify TLDS switch

* Address PR feedback, and a nit

1 files changed, 147 insertions, 0 deletions

diff --git a/Ryujinx.Graphics/Shader/Translation/Optimizations/Simplification.cs b/Ryujinx.Graphics/Shader/Translation/Optimizations/Simplification.cs
new file mode 100644
index 00000000..56b1543f
--- /dev/null
+++ b/Ryujinx.Graphics/Shader/Translation/Optimizations/Simplification.cs
@@ -0,0 +1,147 @@
+using Ryujinx.Graphics.Shader.IntermediateRepresentation;
+
+using static Ryujinx.Graphics.Shader.IntermediateRepresentation.OperandHelper;
+
+namespace Ryujinx.Graphics.Shader.Translation.Optimizations
+{
+    static class Simplification
+    {
+        private const int AllOnes = ~0;
+
+        public static void Simplify(Operation operation)
+        {
+            switch (operation.Inst)
+            {
+                case Instruction.Add:
+                case Instruction.BitwiseExclusiveOr:
+                    TryEliminateBinaryOpComutative(operation, 0);
+                    break;
+
+                case Instruction.BitwiseAnd:
+                    TryEliminateBitwiseAnd(operation);
+                    break;
+
+                case Instruction.BitwiseOr:
+                    TryEliminateBitwiseOr(operation);
+                    break;
+
+                case Instruction.ConditionalSelect:
+                    TryEliminateConditionalSelect(operation);
+                    break;
+
+                case Instruction.Divide:
+                    TryEliminateBinaryOpY(operation, 1);
+                    break;
+
+                case Instruction.Multiply:
+                    TryEliminateBinaryOpComutative(operation, 1);
+                    break;
+
+                case Instruction.ShiftLeft:
+                case Instruction.ShiftRightS32:
+                case Instruction.ShiftRightU32:
+                case Instruction.Subtract:
+                    TryEliminateBinaryOpY(operation, 0);
+                    break;
+            }
+        }
+
+        private static void TryEliminateBitwiseAnd(Operation operation)
+        {
+            //Try to recognize and optimize those 3 patterns (in order):
+            //x & 0xFFFFFFFF == x,          0xFFFFFFFF & y == y,
+            //x & 0x00000000 == 0x00000000, 0x00000000 & y == 0x00000000
+            Operand x = operation.GetSource(0);
+            Operand y = operation.GetSource(1);
+
+            if (IsConstEqual(x, AllOnes))
+            {
+                operation.TurnIntoCopy(y);
+            }
+            else if (IsConstEqual(y, AllOnes))
+            {
+                operation.TurnIntoCopy(x);
+            }
+            else if (IsConstEqual(x, 0) || IsConstEqual(y, 0))
+            {
+                operation.TurnIntoCopy(Const(0));
+            }
+        }
+
+        private static void TryEliminateBitwiseOr(Operation operation)
+        {
+            //Try to recognize and optimize those 3 patterns (in order):
+            //x | 0x00000000 == x,          0x00000000 | y == y,
+            //x | 0xFFFFFFFF == 0xFFFFFFFF, 0xFFFFFFFF | y == 0xFFFFFFFF
+            Operand x = operation.GetSource(0);
+            Operand y = operation.GetSource(1);
+
+            if (IsConstEqual(x, 0))
+            {
+                operation.TurnIntoCopy(y);
+            }
+            else if (IsConstEqual(y, 0))
+            {
+                operation.TurnIntoCopy(x);
+            }
+            else if (IsConstEqual(x, AllOnes) || IsConstEqual(y, AllOnes))
+            {
+                operation.TurnIntoCopy(Const(AllOnes));
+            }
+        }
+
+        private static void TryEliminateBinaryOpY(Operation operation, int comparand)
+        {
+            Operand x = operation.GetSource(0);
+            Operand y = operation.GetSource(1);
+
+            if (IsConstEqual(y, comparand))
+            {
+                operation.TurnIntoCopy(x);
+            }
+        }
+
+        private static void TryEliminateBinaryOpComutative(Operation operation, int comparand)
+        {
+            Operand x = operation.GetSource(0);
+            Operand y = operation.GetSource(1);
+
+            if (IsConstEqual(x, comparand))
+            {
+                operation.TurnIntoCopy(y);
+            }
+            else if (IsConstEqual(y, comparand))
+            {
+                operation.TurnIntoCopy(x);
+            }
+        }
+
+        private static void TryEliminateConditionalSelect(Operation operation)
+        {
+            Operand cond = operation.GetSource(0);
+
+            if (cond.Type != OperandType.Constant)
+            {
+                return;
+            }
+
+            //The condition is constant, we can turn it into a copy, and select
+            //the source based on the condition value.
+            int srcIndex = cond.Value != 0 ? 1 : 2;
+
+            Operand source = operation.GetSource(srcIndex);
+
+            operation.TurnIntoCopy(source);
+        }
+
+        private static bool IsConstEqual(Operand operand, int comparand)
+        {
+            if (operand.Type != OperandType.Constant)
+            {
+                return false;
+            }
+
+            return operand.Value == comparand;
+        }
+    }
+}
\ No newline at end of file