[llvm] [DXIL] Add GroupMemoryBarrierWithGroupSync intrinsic (PR #114349)

[Justin Bogner via llvm-commits]

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@@ -294,6 +294,57 @@ class Attributes<Version ver = DXIL1_0, list<DXILAttribute> attrs> {
   list<DXILAttribute> op_attrs = attrs;
 }
 
+defvar BarrierMode_DeviceMemoryBarrier              = 2;
+defvar BarrierMode_DeviceMemoryBarrierWithGroupSync = 3;
+defvar BarrierMode_GroupMemoryBarrier               = 8;
+defvar BarrierMode_GroupMemoryBarrierWithGroupSync  = 9;
+defvar BarrierMode_AllMemoryBarrier                 = 10;
+defvar BarrierMode_AllMemoryBarrierWithGroupSync    = 11;
+
+// Intrinsic arg selection
+class IntrinArgSelectType;
+def IntrinArgSelect_Index : IntrinArgSelectType;
+def IntrinArgSelect_I8    : IntrinArgSelectType;
+def IntrinArgSelect_I32   : IntrinArgSelectType;
+
+class IntrinArgSelect<IntrinArgSelectType type_, int value_> {
+  IntrinArgSelectType type = type_;
+  int value = value_;
+}
+class IntrinArgIndex<int index> : IntrinArgSelect<IntrinArgSelect_Index, index>;
+class IntrinArgI8   <int value> : IntrinArgSelect<IntrinArgSelect_I8,    value>;
+class IntrinArgI32  <int value> : IntrinArgSelect<IntrinArgSelect_I32,   value>;
+
+// Select which intrinsic to lower from for a DXILOp.
+// If the intrinsic is the only argument given to IntrinSelect, then the arguments of the intrinsic will be copied
+// in the same order. Example:
+//   let intrinsic_selects = [
+//     IntrinSelect<int_dx_my_intrinsic>,
+//     IntrinSelect<int_dx_my_intrinsic2>,
+//   ]
+//=========================================================================================
+// Using IntrinArgIndex<>, arguments of the intrinsic can be copied in specific order:
+//   let intrinsic_selects = [
+//     IntrinSelect<int_dx_my_intrinsic,
+//       [IntrinArgIndex<2>, IntrinArgIndex<1>, IntrinArgIndex<0>> ]
+//     >,
+//   ]
+//=========================================================================================
+// to the dxil op. This can be used in conjunction with IntrinArgIndex:
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bogner wrote:

Looks like this is missing some text

https://github.com/llvm/llvm-project/pull/114349