[dxbc] Fix UAV write test

We broke this during the null descriptor refactor. Also make it so that
we don't generate conditionals when there's nothing to test.

src/dxbc/dxbc_compiler.cpp

@@ -2273,21 +2273,8 @@ namespace dxvk {
                && bufferInfo.type != DxbcResourceType::Typed
                && isUav;
 
-    // Perform atomic operations on UAVs only if the UAV
+    // Perform atomic operations on UAVs only if the invocation is alive
-    // is bound and if there is nothing else stopping us.
+    DxbcConditional cond = emitBeginPsKillTest();
-    DxbcConditional cond;
-    
-    if (isUav) {
-      uint32_t writeTest = emitUavWriteTest(bufferInfo);
-      
-      cond.labelIf  = m_module.allocateId();
-      cond.labelEnd = m_module.allocateId();
-      
-      m_module.opSelectionMerge(cond.labelEnd, spv::SelectionControlMaskNone);
-      m_module.opBranchConditional(writeTest, cond.labelIf, cond.labelEnd);
-      
-      m_module.opLabel(cond.labelIf);
-    }
     
     // Retrieve destination pointer for the atomic operation>
     const DxbcRegisterPointer pointer = emitGetAtomicPointer(
@@ -2413,11 +2400,7 @@ namespace dxvk {
     if (isImm)
       emitRegisterStore(ins.dst[0], value);
     
-    // End conditional block
+    emitEndPsKillTest(cond);
-    if (isUav) {
-      m_module.opBranch(cond.labelEnd);
-      m_module.opLabel (cond.labelEnd);
-    }
   }
   
   
@@ -2425,30 +2408,22 @@ namespace dxvk {
     // imm_atomic_alloc and imm_atomic_consume have the following operands:
     //    (dst0) The register that will hold the old counter value
     //    (dst1) The UAV whose counter is going to be modified
-    const DxbcBufferInfo bufferInfo = getBufferInfo(ins.dst[1]);
-    
     const uint32_t registerId = ins.dst[1].idx[0].offset;
     
     if (m_uavs.at(registerId).ctrId == 0)
       m_uavs.at(registerId).ctrId = emitDclUavCounter(registerId);
     
-    // Only perform the operation if the UAV is bound
+    // Only perform the operation if the invocation is alive
-    uint32_t writeTest = emitUavWriteTest(bufferInfo);
+    DxbcConditional cond = emitBeginPsKillTest();
-    
-    DxbcConditional cond;
-    cond.labelIf  = m_module.allocateId();
-    cond.labelEnd = m_module.allocateId();
-    
-    m_module.opSelectionMerge(cond.labelEnd, spv::SelectionControlMaskNone);
-    m_module.opBranchConditional(writeTest, cond.labelIf, cond.labelEnd);
-    
-    m_module.opLabel(cond.labelIf);
 
     // Only use subgroup ops on compute to avoid having to
     // deal with helper invocations or hardware limitations
     bool useSubgroupOps = m_moduleInfo.options.useSubgroupOpsForAtomicCounters
       && m_programInfo.type() == DxbcProgramType::ComputeShader;
 
+    // Current block ID used in a phi later on
+    uint32_t baseBlockId = m_module.getBlockId();
+
     // In case we have subgroup ops enabled, we need to
     // count the number of active lanes, the lane index,
     // and we need to perform the atomic op conditionally
@@ -2550,7 +2525,7 @@ namespace dxvk {
 
       std::array<SpirvPhiLabel, 2> phiLabels = {{
         { value.id, elect.labelIf },
-        { undef,    cond.labelIf  },
+        { undef,    baseBlockId   },
       }};
 
       value.id = m_module.opPhi(typeId,
@@ -2562,10 +2537,7 @@ namespace dxvk {
     
     // Store the result
     emitRegisterStore(ins.dst[0], value);
-    
+    emitEndPsKillTest(cond);
-    // End conditional block
-    m_module.opBranch(cond.labelEnd);
-    m_module.opLabel (cond.labelEnd);
   }
   
   
@@ -3677,17 +3649,8 @@ namespace dxvk {
     //    (src1) The value to store
     const DxbcBufferInfo uavInfo = getBufferInfo(ins.dst[0]);
     
-    // Execute write op only if the UAV is bound
+    // Execute write op only if the invocation is active
-    uint32_t writeTest = emitUavWriteTest(uavInfo);
+    DxbcConditional cond = emitBeginPsKillTest();
-    
-    DxbcConditional cond;
-    cond.labelIf  = m_module.allocateId();
-    cond.labelEnd = m_module.allocateId();
-    
-    m_module.opSelectionMerge   (cond.labelEnd, spv::SelectionControlMaskNone);
-    m_module.opBranchConditional(writeTest, cond.labelIf, cond.labelEnd);
-    
-    m_module.opLabel(cond.labelIf);
     
     // Load texture coordinates
     DxbcRegisterValue texCoord = emitLoadTexCoord(ins.src[0], uavInfo.image);
@@ -3703,9 +3666,7 @@ namespace dxvk {
       m_module.opLoad(uavInfo.typeId, uavInfo.varId),
       texCoord.id, texValue.id, SpirvImageOperands());
 
-    // End conditional block
+    emitEndPsKillTest(cond);
-    m_module.opBranch(cond.labelEnd);
-    m_module.opLabel (cond.labelEnd);
   }
   
   
@@ -5152,21 +5113,8 @@ namespace dxvk {
     bool isSsbo = m_moduleInfo.options.minSsboAlignment <= bufferInfo.align
                && !isTgsm;
     
-    // Perform UAV writes only if the UAV is bound and if there
+    // Perform UAV writes only if the invocation is active
-    // is nothing else preventing us from writing to it.
+    DxbcConditional cond = emitBeginPsKillTest();
-    DxbcConditional cond;
-    
-    if (!isTgsm) {
-      uint32_t writeTest = emitUavWriteTest(bufferInfo);
-      
-      cond.labelIf  = m_module.allocateId();
-      cond.labelEnd = m_module.allocateId();
-      
-      m_module.opSelectionMerge(cond.labelEnd, spv::SelectionControlMaskNone);
-      m_module.opBranchConditional(writeTest, cond.labelIf, cond.labelEnd);
-      
-      m_module.opLabel(cond.labelIf);
-    }
     
     // Perform the actual write operation
     uint32_t bufferId = isTgsm || isSsbo ? 0 : m_module.opLoad(bufferInfo.typeId, bufferInfo.varId);
@@ -5229,11 +5177,7 @@ namespace dxvk {
                         | spv::MemorySemanticsAcquireReleaseMask));
     }
 
-    // End conditional block
+    emitEndPsKillTest(cond);
-    if (!isTgsm) {
-      m_module.opBranch(cond.labelEnd);
-      m_module.opLabel (cond.labelEnd);
-    }
   }
 
 
@@ -6483,20 +6427,32 @@ namespace dxvk {
   }
   
   
-  uint32_t DxbcCompiler::emitUavWriteTest(const DxbcBufferInfo& uav) {
+  DxbcConditional DxbcCompiler::emitBeginPsKillTest() {
-    uint32_t typeId = m_module.defBoolType();
+    if (!m_ps.killState)
-    uint32_t testId = 0;
+      return DxbcConditional();
 
-    if (m_ps.killState != 0) {
+    uint32_t boolId = m_module.defBoolType();
-      uint32_t killState = m_module.opLoad(typeId, m_ps.killState);
+    uint32_t killState = m_module.opLoad(boolId, m_ps.killState);
+    uint32_t testId = m_module.opLogicalNot(boolId, killState);
 
-      testId = m_module.opLogicalAnd(typeId, testId,
+    DxbcConditional cond;
-        m_module.opLogicalNot(typeId, killState));
+    cond.labelIf  = m_module.allocateId();
-    } else {
+    cond.labelEnd = m_module.allocateId();
-      testId = m_module.constBool(true);
+    
+    m_module.opSelectionMerge(cond.labelEnd, spv::SelectionControlMaskNone);
+    m_module.opBranchConditional(testId, cond.labelIf, cond.labelEnd);
+    
+    m_module.opLabel(cond.labelIf);
+    return cond;
   }
 
-    return testId;
+
+  void DxbcCompiler::emitEndPsKillTest(const DxbcConditional& cond) {
+    if (!m_ps.killState)
+      return;
+
+    m_module.opBranch(cond.labelEnd);
+    m_module.opLabel(cond.labelEnd);
   }
 
 

src/dxbc/dxbc_compiler.h

@@ -1063,8 +1063,9 @@ namespace dxvk {
     
     ///////////////////////////////
     // Some state checking methods
-    uint32_t emitUavWriteTest(
+    DxbcConditional emitBeginPsKillTest();
-      const DxbcBufferInfo&         uav);
+
+    void emitEndPsKillTest(const DxbcConditional& cond);
     
     //////////////////////////////////////
     // Common function definition methods