[mlir][dxsa] Add dcl_stream instruction

mlir/include/mlir/Dialect/DXSA/IR/DXSAOps.td

@@ -1054,4 +1054,22 @@ def DXSA_DclSampler : DXSA_Op<"dcl_sampler"> {
   let hasVerifier = 1;
 }
 
+def DXSA_DclStream : DXSA_Op<"dcl_stream"> {
+  let summary = "declares a geometry shader (GS) output stream";
+  let description = [{
+    The `dxsa.dcl_stream` operation declares a geometry shader (GS) output stream.
+
+    The `$index` must be in the range [0, 3].
+
+    Example:
+
+    ```mlir
+    dxsa.dcl_stream 0
+    ```
+  }];
+  let arguments = (ins ConfinedAttr<I32Attr,
+      [IntNonNegative, IntMaxValue<3>]>:$index);
+  let assemblyFormat = [{ $index attr-dict }];
+}
+
 #endif // DXSA_OPS

mlir/lib/Target/DXSA/BinaryParser.cpp

@@ -595,6 +595,11 @@ class DXBuilder {
     return dxsa::DclMaxOutputVertexCount::create(builder, loc, count);
   }
 
+  Instruction buildDclStream(uint32_t index, Location loc) {
+    return dxsa::DclStream::create(builder, loc,
+                                   builder.getI32IntegerAttr(index));
+  }
+
   Instruction buildDclInputPs(dxsa::InterpolationMode interpolationMode,
                               Operand operand, Location loc) {
     auto interpolationModeAttr = dxsa::InterpolationModeAttr::get(
@@ -1168,6 +1173,22 @@ class Parser {
     return builder.buildDclMaxOutputVertexCount(count, loc);
   }
 
+  FailureOr<Instruction> parseDclStream(Location loc) {
+    auto operand = parseInlineOperand();
+    FAILURE_IF_FAILED(operand);
+    if (operand->getType() != dxsa::InlineOperandType::stream)
+      return emitError(loc, "unexpected operand type: ")
+             << dxsa::stringifyInlineOperandType(operand->getType());
+    if (operand->getComponents() != 0)
+      return emitError(loc, "unexpected number of components: ")
+             << operand->getComponents();
+    auto indexArray = operand->getIndex();
+    if (!indexArray || indexArray.size() != 1)
+      return emitError(loc, "unsupported index dimension: ")
+             << (indexArray ? indexArray.size() : 0);
+    return builder.buildDclStream(static_cast<uint32_t>(indexArray[0]), loc);
+  }
+
   FailureOr<dxsa::InterpolationMode>
   parseInterpolationMode(uint32_t opcodeToken, Location loc) {
     auto rawInterpolationMode =
@@ -1492,6 +1513,9 @@ class Parser {
     case D3D10_SB_OPCODE_DCL_MAX_OUTPUT_VERTEX_COUNT:
       result = parseDclMaxOutputVertexCount(loc);
       break;
+    case D3D11_SB_OPCODE_DCL_STREAM:
+      result = parseDclStream(loc);
+      break;
     case D3D10_SB_OPCODE_DCL_INPUT_PS:
       result = parseDclInputPs(opcodeToken, loc);
       break;

mlir/test/Target/DXSA/dcl_stream.mlir

@@ -0,0 +1,6 @@
+// RUN: mlir-translate --import-dxsa-bin %S/inputs/dcl_stream.bin | FileCheck %s
+
+// CHECK:      module {
+// CHECK-NEXT:   dxsa.dcl_stream 0
+// CHECK-NEXT:   dxsa.dcl_stream 3
+// CHECK-NEXT: }

mlir/test/Target/DXSA/dcl_stream_invalid.mlir

@@ -0,0 +1,9 @@
+// RUN: mlir-opt %s -split-input-file -verify-diagnostics
+
+// expected-error@+1 {{attribute 'index' failed to satisfy constraint: 32-bit signless integer attribute whose value is non-negative whose maximum value is 3}}
+dxsa.dcl_stream -1
+
+// -----
+
+// expected-error@+1 {{attribute 'index' failed to satisfy constraint: 32-bit signless integer attribute whose value is non-negative whose maximum value is 3}}
+dxsa.dcl_stream 4