[Mlir-commits] [mlir] [MLIR][NVVM] Add summary and description fields for several OPs (PR #156726)

[Durgadoss R]

================
@@ -657,6 +918,35 @@ def NVVM_Barrier0Op : NVVM_Op<"barrier0"> {
 }
 
 def NVVM_BarrierOp : NVVM_Op<"barrier", [AttrSizedOperandSegments]> {
+  let summary = "CTA Barrier Synchronization Op";
+  let description = [{
+    The `nvvm.barrier` operation performs barrier synchronization and communication 
+    within a CTA (Cooperative Thread Array). It causes executing threads to wait for 
+    all non-exited threads participating in the barrier to arrive.
+
+    The operation takes two optional operands:
+
+    - `barrierId`: Specifies a logical barrier resource with value 0 through 15. 
+      Each CTA instance has sixteen barriers numbered 0..15. Defaults to 0 if not specified.
+    - `numberOfThreads`: Specifies the number of threads participating in the barrier. 
+      When specified, the value must be a multiple of the warp size. If not specified, 
+      all threads in the CTA participate in the barrier.
+
+    The barrier operation guarantees that when the barrier completes, prior memory 
+    accesses requested by participating threads are performed relative to all threads 
+    participating in the barrier. It also ensures that no new memory access is 
+    requested by participating threads before the barrier completes.
+
+    When a barrier completes, the waiting threads are restarted without delay, and 
+    the barrier is reinitialized so that it can be immediately reused.
+
+    This operation generates an aligned barrier, indicating that all threads in the CTA 
+    will execute the same barrier instruction. Behavior is undefined if not all threads 
+    in the CTA reach this instruction.
----------------
durga4github wrote:

a minor re-phrasing:
```
Behavior is undefined if all threads in the CTA do not reach this instruction.
```

https://github.com/llvm/llvm-project/pull/156726