From 619195dd57ffeae6762a22933960050114c4eb88 Mon Sep 17 00:00:00 2001
From: Vladislav Dzhidzhoev <vdzhidzhoev@accesssoftek.com>
Date: Wed, 24 Jun 2026 22:29:42 +0200
Subject: [PATCH] [mlir][dxsa] Add nop instruction

Depends on https://github.com/access-softek/llvm-project/pull/198.
---
 mlir/include/mlir/Dialect/DXSA/IR/DXSAOps.td | 13 +++++++++++++
 mlir/lib/Target/DXSA/BinaryParser.cpp        |  2 ++
 mlir/test/Target/DXSA/nop.test               |  9 +++++++++
 3 files changed, 24 insertions(+)
 create mode 100644 mlir/test/Target/DXSA/nop.test

diff --git a/mlir/include/mlir/Dialect/DXSA/IR/DXSAOps.td b/mlir/include/mlir/Dialect/DXSA/IR/DXSAOps.td
index 70f7a71382a8..99d8edbe9301 100644
--- a/mlir/include/mlir/Dialect/DXSA/IR/DXSAOps.td
+++ b/mlir/include/mlir/Dialect/DXSA/IR/DXSAOps.td
@@ -1425,4 +1425,17 @@ def DXSA_DclThreadGroup : DXSA_Op<"dcl_thread_group"> {
   let hasVerifier = 1;
 }
 
+def DXSA_Nop : DXSA_NullaryOp<"nop"> {
+  let summary = "no operation";
+  let description = [{
+    The `dxsa.nop` operation has no effect.
+
+    Example:
+
+    ```mlir
+    dxsa.nop
+    ```
+  }];
+}
+
 #endif // DXSA_OPS
diff --git a/mlir/lib/Target/DXSA/BinaryParser.cpp b/mlir/lib/Target/DXSA/BinaryParser.cpp
index 08dd7dc8e9ce..553850cb6efa 100644
--- a/mlir/lib/Target/DXSA/BinaryParser.cpp
+++ b/mlir/lib/Target/DXSA/BinaryParser.cpp
@@ -2628,6 +2628,8 @@ class Parser {
     case D3D10_SB_OPCODE_RET:
       return PLAIN_OP(Ret, 0, 0, HasPreciseAttr::No);
     // Other instructions
+    case D3D10_SB_OPCODE_NOP:
+      return PLAIN_OP(Nop, 0, 0);
     case D3D11_SB_OPCODE_SYNC:
       return parseSync(*opcodeToken0, beginOffset, instructionLengthInTokens,
                        getLocation());
diff --git a/mlir/test/Target/DXSA/nop.test b/mlir/test/Target/DXSA/nop.test
new file mode 100644
index 000000000000..5c129c2bdc86
--- /dev/null
+++ b/mlir/test/Target/DXSA/nop.test
@@ -0,0 +1,9 @@
+// RUN: mlir-translate --import-dxsa-hex %s | FileCheck %s
+// RUN: mlir-translate --import-dxsa-hex %s | mlir-opt --verify-roundtrip
+
+// CHECK:      dxsa.module {
+
+// CHECK-NEXT:   dxsa.nop
+0x0100003A
+
+// CHECK-NEXT: }