From d522e19babd4f68d8c7bedadaf1a4e32f4be3d69 Mon Sep 17 00:00:00 2001
From: Philip Rebohle <philip.rebohle@tu-dortmund.de>
Date: Sat, 20 Jan 2018 10:21:27 +0100
Subject: [PATCH] [dxbc] Implemented SampleB instruction

---
 src/dxbc/dxbc_compiler.cpp | 21 +++++++++++++++------
 src/dxbc/dxbc_defs.cpp     |  8 +++++++-
 2 files changed, 22 insertions(+), 7 deletions(-)

diff --git a/src/dxbc/dxbc_compiler.cpp b/src/dxbc/dxbc_compiler.cpp
index e2cd6f86..81eb7c1e 100644
--- a/src/dxbc/dxbc_compiler.cpp
+++ b/src/dxbc/dxbc_compiler.cpp
@@ -2564,8 +2564,6 @@ namespace dxvk {
   
   
   void DxbcCompiler::emitTextureSample(const DxbcShaderInstruction& ins) {
-    // TODO support remaining sample ops
-    
     // All sample instructions have at least these operands:
     //    (dst0) The destination register
     //    (src0) Texture coordinates
@@ -2622,10 +2620,11 @@ namespace dxvk {
       ? emitRegisterLoad(ins.src[4], coordLayerMask)
       : DxbcRegisterValue();
     
-    // Explicit LOD value for certain sample operations
-    const bool hasExplicitLod = ins.op == DxbcOpcode::SampleL;
+    // LOD for certain sample operations
+    const bool hasLod = ins.op == DxbcOpcode::SampleL
+                     || ins.op == DxbcOpcode::SampleB;
     
-    const DxbcRegisterValue explicitLod = hasExplicitLod
+    const DxbcRegisterValue lod = hasLod
       ? emitRegisterLoad(ins.src[3], DxbcRegMask(true, false, false, false))
       : DxbcRegisterValue();
     
@@ -2716,13 +2715,23 @@ namespace dxvk {
       // Sample operation with explicit LOD
       case DxbcOpcode::SampleL: {
         imageOperands.flags |= spv::ImageOperandsLodMask;
-        imageOperands.sLod = explicitLod.id;
+        imageOperands.sLod = lod.id;
         
         result.id = m_module.opImageSampleExplicitLod(
           getVectorTypeId(result.type), sampledImageId, coord.id,
           imageOperands);
       } break;
       
+      // Sample operation with LOD bias
+      case DxbcOpcode::SampleB: {
+        imageOperands.flags |= spv::ImageOperandsBiasMask;
+        imageOperands.sLodBias = lod.id;
+        
+        result.id = m_module.opImageSampleImplicitLod(
+          getVectorTypeId(result.type), sampledImageId, coord.id,
+          imageOperands);
+      } break;
+      
       default:
         Logger::warn(str::format(
           "DxbcCompiler: Unhandled instruction: ",
diff --git a/src/dxbc/dxbc_defs.cpp b/src/dxbc/dxbc_defs.cpp
index 945b5941..cd265a5e 100644
--- a/src/dxbc/dxbc_defs.cpp
+++ b/src/dxbc/dxbc_defs.cpp
@@ -372,7 +372,13 @@ namespace dxvk {
       { DxbcOperandKind::SrcReg, DxbcScalarType::Float32 },
     } },
     /* SampleB                              */
-    { },
+    { 5, DxbcInstClass::TextureSample, {
+      { DxbcOperandKind::DstReg, DxbcScalarType::Float32 },
+      { DxbcOperandKind::SrcReg, DxbcScalarType::Float32 },
+      { DxbcOperandKind::SrcReg, DxbcScalarType::Float32 },
+      { DxbcOperandKind::SrcReg, DxbcScalarType::Float32 },
+      { DxbcOperandKind::SrcReg, DxbcScalarType::Float32 },
+    } },
     /* Sqrt                                 */
     { 2, DxbcInstClass::VectorAlu, {
       { DxbcOperandKind::DstReg, DxbcScalarType::Float32 },