[SPIRV] Allow globallycoherent on DescriptorHeap accesses (#7740)

tools/clang/lib/SPIRV/SpirvEmitter.cpp

@@ -6658,6 +6658,8 @@ SpirvEmitter::doCXXOperatorCallExpr(const CXXOperatorCallExpr *expr,
       auto *decl = cast<VarDecl>(declRefExpr->getDecl());
       auto *var = declIdMapper.createResourceHeap(decl, resourceType);
 
+      if (hlsl::HasHLSLGloballyCoherent(resourceType))
+        spvBuilder.decorateCoherent(var, baseExpr->getExprLoc());
       auto *index = doExpr(indexExpr);
 
       if (spirvOptions.useDescriptorHeap) {

tools/clang/test/CodeGenSPIRV/sm6_6.descriptorheap.globallycoherent.hlsl

@@ -0,0 +1,54 @@
+// RUN: %dxc -T cs_6_6 -E CSMain -spirv -DTYPE=0 %s | FileCheck %s --check-prefix=TYPE0
+// RUN: %dxc -T cs_6_6 -E CSMain -spirv -DTYPE=1 %s | FileCheck %s --check-prefix=TYPE1
+// RUN: %dxc -T cs_6_6 -E CSMain -spirv -DTYPE=2 %s | FileCheck %s --check-prefix=TYPE2
+// RUN: %dxc -T cs_6_6 -E CSMain -spirv -DTYPE=3 %s | FileCheck %s --check-prefix=TYPE3
+
+// TYPE=0: direct ResourceDescriptorHeap[] init of a `globallycoherent` static.
+// TYPE0-DAG: OpDecorate %ResourceDescriptorHeap{{(_[0-9]+)?}} DescriptorSet 0
+// TYPE0-DAG: OpDecorate %ResourceDescriptorHeap{{(_[0-9]+)?}} Binding 0
+// TYPE0-DAG: OpDecorate %ResourceDescriptorHeap{{(_[0-9]+)?}} Coherent
+
+// TYPE=1: bindless array carries the qualifier.
+// TYPE1-DAG: OpDecorate %FakeHeapOfA DescriptorSet 0
+// TYPE1-DAG: OpDecorate %FakeHeapOfA Binding 0
+// TYPE1-DAG: OpDecorate %FakeHeapOfA Coherent
+
+// TYPE=2: stand-alone `globallycoherent` UAV.
+// TYPE2-DAG: OpDecorate %A DescriptorSet 0
+// TYPE2-DAG: OpDecorate %A Binding 0
+// TYPE2-DAG: OpDecorate %A Coherent
+
+// TYPE=3: heap access lives inside a `globallycoherent`-returning helper, and 
+// a `globallycoherent static` captures the result.
+// TYPE3-DAG: OpDecorate %ResourceDescriptorHeap{{(_[0-9]+)?}} DescriptorSet 0
+// TYPE3-DAG: OpDecorate %ResourceDescriptorHeap{{(_[0-9]+)?}} Binding {{[0-9]+}}
+// TYPE3-DAG: OpDecorate %ResourceDescriptorHeap{{(_[0-9]+)?}} Coherent
+// TYPE3-NOT: OpDecorate %Buf Coherent
+
+#if TYPE == 0
+globallycoherent static RWStructuredBuffer<uint> A = ResourceDescriptorHeap[0];
+#elif TYPE == 1
+globallycoherent RWStructuredBuffer<uint> FakeHeapOfA[];
+globallycoherent static RWStructuredBuffer<uint> A = FakeHeapOfA[0];
+#elif TYPE == 2
+globallycoherent RWStructuredBuffer<uint> A;
+#elif TYPE == 3
+uint BindlessUAV_Buf;
+typedef RWByteAddressBuffer SafeTypeBuf;
+globallycoherent SafeTypeBuf GetBuf() { return ResourceDescriptorHeap[BindlessUAV_Buf]; }
+static const globallycoherent SafeTypeBuf A = GetBuf();
+#endif
+
+[numthreads(64, 1, 1)]
+void CSMain(uint3 ThreadId : SV_DispatchThreadId)
+{
+#if TYPE == 3
+    A.InterlockedAdd(0, 1);
+    AllMemoryBarrierWithGroupSync();
+    A.Store(0, 42);
+#else
+    InterlockedAdd(A[0], 1);
+    AllMemoryBarrierWithGroupSync();
+    InterlockedAdd(A[1], A[0]);
+#endif
+}