Fix depth write mask

AndresTraks · Jan 26, 2025 · 3aaa264 · 3aaa264
1 parent 6a83bfc
commit 3aaa264
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Showing 6 changed files with 39 additions and 16 deletions.
diff --git a/DirectXShaderModel/AsmWriter.cs b/DirectXShaderModel/AsmWriter.cs
@@ -30,8 +30,8 @@ static string GetDestinationName(Instruction instruction)
         {
             int destIndex = instruction.GetDestinationParamIndex();
             string registerName = instruction.GetParamRegisterName(destIndex);
-            const int registerLength = 4;
-            string writeMaskName = instruction.GetDestinationWriteMaskName(registerLength, false);
+            int destinationLength = instruction.GetDestinationSemanticSize();
+            string writeMaskName = instruction.GetDestinationWriteMaskName(destinationLength);
 
             return $"{registerName}{writeMaskName}";
         }

diff --git a/DirectXShaderModel/D3D10Instruction.cs b/DirectXShaderModel/D3D10Instruction.cs
@@ -275,7 +275,7 @@ public override string GetSourceSwizzleName(int srcIndex, int? destinationLength
         public override string GetDeclSemantic()
         {
             string name;
-            switch (GetOperandType(0))
+            switch (GetOperandType(GetDestinationParamIndex()))
             {
                 case OperandType.Input:
                     name = "SV_Position";
@@ -294,6 +294,15 @@ public override string GetDeclSemantic()
             return name;
         }
 
+        public override int GetDestinationSemanticSize()
+        {
+            if (GetOperandType(GetDestinationParamIndex()) == OperandType.OutputDepth)
+            {
+                return 1;
+            }
+            return 4;
+        }
+
         private byte[] GetOperandValueBytes(int index, int componentIndex)
         {
             Span<uint> span = OperandTokens.GetSpan(index);

diff --git a/DirectXShaderModel/D3D9Instruction.cs b/DirectXShaderModel/D3D9Instruction.cs
@@ -146,6 +146,16 @@ public SamplerTextureType GetDeclSamplerTextureType()
             return (SamplerTextureType)((Params[0] >> 27) & 0xF);
         }
 
+        public override int GetDestinationSemanticSize()
+        {
+            RegisterType registerType = GetParamRegisterType(GetDestinationParamIndex());
+            if (registerType == RegisterType.DepthOut)
+            {
+                return 1;
+            }
+            return 4;
+        }
+
         public override int GetDestinationParamIndex()
         {
             if (Opcode == Opcode.Dcl) return 1;

diff --git a/DirectXShaderModel/Instruction.cs b/DirectXShaderModel/Instruction.cs
@@ -21,18 +21,12 @@ public abstract class Instruction
 
         public abstract int GetDestinationWriteMask();
 
-        public string GetDestinationWriteMaskName(int destinationLength, bool hlsl)
+        public string GetDestinationWriteMaskName(int destinationLength)
         {
-            int writeMask = GetDestinationWriteMask();
-            int writeMaskLength = GetDestinationMaskLength();
+            int destinationMask = (1 << destinationLength) - 1;
+            int writeMask = GetDestinationWriteMask() & destinationMask;
 
-            if (!hlsl)
-            {
-                destinationLength = 4; // explicit mask in assembly
-            }
-
-            // Check if mask is the same length and of the form .xyzw
-            if (writeMaskLength == destinationLength && writeMask == ((1 << writeMaskLength) - 1))
+            if (writeMask == destinationMask)
             {
                 return "";
             }
@@ -77,5 +71,7 @@ public byte[] GetSourceSwizzleComponents(int srcIndex)
         public abstract string GetSourceSwizzleName(int srcIndex, int? destinationLength);
 
         public abstract string GetDeclSemantic();
+
+        public abstract int GetDestinationSemanticSize();
     }
 }
diff --git a/Hlsl/HlslSimpleWriter.cs b/Hlsl/HlslSimpleWriter.cs
@@ -353,7 +353,7 @@ private string GetDestinationName(Instruction instruction)
             string registerName = _registers.GetRegisterName(registerKey);
             registerName = registerName ?? instruction.GetParamRegisterName(destIndex);
             int registerLength = _registers.GetRegisterFullLength(registerKey);
-            string writeMaskName = instruction.GetDestinationWriteMaskName(registerLength, true);
+            string writeMaskName = instruction.GetDestinationWriteMaskName(registerLength);
 
             return string.Format("{0}{1}", registerName, writeMaskName);
         }
@@ -452,7 +452,15 @@ private string GetSourceConstantValue(D3D9Instruction instruction, int srcIndex,
             {
                 if (instruction.HasDestination)
                 {
-                    destinationLength = instruction.GetDestinationMaskLength();
+                    int writeMask = instruction.GetDestinationWriteMask();
+                    destinationLength = 0;
+                    for (int i = 0; i < 4; i++)
+                    {
+                        if ((writeMask & (1 << i)) != 0)
+                        {
+                            destinationLength++;
+                        }
+                    }
                 }
                 else
                 {

diff --git a/HlslDecompiler.Tests/ShaderSources/ps_3_0_instruction/semantics.fx b/HlslDecompiler.Tests/ShaderSources/ps_3_0_instruction/semantics.fx
@@ -16,7 +16,7 @@ PS_OUT main(PS_IN i)
 
 	o.color.w = (i.vface >= 0) ? 1 : -1;
 	o.color.xyz = i.vpos.xxy * float3(0, 1, 1) + float3(0.3, 0, 0);
-	o.depth.xyzw = -123456;
+	o.depth = -123456;
 
 	return o;
 }