From afc44850be37f57d96e981925229964771a3e9e0 Mon Sep 17 00:00:00 2001
From: ReinUsesLisp <reinuseslisp@airmail.cc>
Date: Mon, 20 Aug 2018 23:31:10 -0300
Subject: [PATCH] Avoid gpr overwritting on Ld_C instruction (#371)

* Avoid gpr overwritting on LD_C instruction

* Address feedback

* Ignore invalid registers
---
 .../Gal/Shader/ShaderDecodeHelper.cs           |  7 -------
 Ryujinx.Graphics/Gal/Shader/ShaderDecodeMem.cs | 18 +++++++++++++++---
 Ryujinx.Graphics/Gal/Shader/ShaderIrOperGpr.cs |  7 +++++++
 3 files changed, 22 insertions(+), 10 deletions(-)

diff --git a/Ryujinx.Graphics/Gal/Shader/ShaderDecodeHelper.cs b/Ryujinx.Graphics/Gal/Shader/ShaderDecodeHelper.cs
index 7d7b2f6c6..2093f0706 100644
--- a/Ryujinx.Graphics/Gal/Shader/ShaderDecodeHelper.cs
+++ b/Ryujinx.Graphics/Gal/Shader/ShaderDecodeHelper.cs
@@ -35,13 +35,6 @@ namespace Ryujinx.Graphics.Gal.Shader
                 (int)(OpCode >> 20) & 0x3fff);
         }
 
-        public static ShaderIrOperCbuf GetOperCbuf36(long OpCode)
-        {
-            return new ShaderIrOperCbuf(
-                (int)(OpCode >> 36) & 0x1f,
-                (int)(OpCode >> 22) & 0x3fff, GetOperGpr8(OpCode));
-        }
-
         public static ShaderIrOperGpr GetOperGpr8(long OpCode)
         {
             return new ShaderIrOperGpr((int)(OpCode >> 8) & 0xff);
diff --git a/Ryujinx.Graphics/Gal/Shader/ShaderDecodeMem.cs b/Ryujinx.Graphics/Gal/Shader/ShaderDecodeMem.cs
index e794e1f87..a183b0c69 100644
--- a/Ryujinx.Graphics/Gal/Shader/ShaderDecodeMem.cs
+++ b/Ryujinx.Graphics/Gal/Shader/ShaderDecodeMem.cs
@@ -52,23 +52,35 @@ namespace Ryujinx.Graphics.Gal.Shader
 
         public static void Ld_C(ShaderIrBlock Block, long OpCode)
         {
-            int Type = (int)(OpCode >> 48) & 7;
+            int CbufPos   = (int)(OpCode >> 22) & 0x3fff;
+            int CbufIndex = (int)(OpCode >> 36) & 0x1f;
+            int Type      = (int)(OpCode >> 48) & 7;
 
             if (Type > 5)
             {
                 throw new InvalidOperationException();
             }
 
+            ShaderIrOperGpr Temp = ShaderIrOperGpr.MakeTemporary();
+
+            Block.AddNode(new ShaderIrAsg(Temp, GetOperGpr8(OpCode)));
+
             int Count = Type == 5 ? 2 : 1;
 
             for (int Index = 0; Index < Count; Index++)
             {
-                ShaderIrOperCbuf OperA = GetOperCbuf36(OpCode);
-                ShaderIrOperGpr  OperD = GetOperGpr0  (OpCode);
+                ShaderIrOperCbuf OperA = new ShaderIrOperCbuf(CbufIndex, CbufPos, Temp);
+
+                ShaderIrOperGpr OperD = GetOperGpr0(OpCode);
 
                 OperA.Pos   += Index;
                 OperD.Index += Index;
 
+                if (!OperD.IsValidRegister)
+                {
+                    break;
+                }
+
                 ShaderIrNode Node = OperA;
 
                 if (Type < 4)
diff --git a/Ryujinx.Graphics/Gal/Shader/ShaderIrOperGpr.cs b/Ryujinx.Graphics/Gal/Shader/ShaderIrOperGpr.cs
index 5c69d6a67..9dd196e69 100644
--- a/Ryujinx.Graphics/Gal/Shader/ShaderIrOperGpr.cs
+++ b/Ryujinx.Graphics/Gal/Shader/ShaderIrOperGpr.cs
@@ -6,11 +6,18 @@ namespace Ryujinx.Graphics.Gal.Shader
 
         public bool IsConst => Index == ZRIndex;
 
+        public bool IsValidRegister => (Index <= ZRIndex);
+
         public int Index { get; set; }
 
         public ShaderIrOperGpr(int Index)
         {
             this.Index = Index;
         }
+
+        public static ShaderIrOperGpr MakeTemporary(int Index = 0)
+        {
+            return new ShaderIrOperGpr(0x100 + Index);
+        }
     }
 }
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