[HLSL] Add Increment/DecrementCounter methods to structured buffers (#114148)

Introduces `__builtin_hlsl_buffer_update_counter` clang buildin that is
used to implement the `IncrementCounter` and `DecrementCounter` methods
on `RWStructuredBuffer` and `RasterizerOrderedStructuredBuffer` (see
Note).

The builtin is translated to LLVM intrisic `llvm.dx.bufferUpdateCounter`
or `llvm.spv.bufferUpdateCounter`.

Introduces `BuiltinTypeMethodBuilder` helper in `HLSLExternalSemaSource`
that enables adding methods to builtin types using builder pattern like
this:
```
   BuiltinTypeMethodBuilder(Sema, RecordBuilder, "MethodName", ReturnType)
       .addParam("param_name", Type, InOutModifier)
       .callBuiltin("buildin_name", { BuiltinParams })
       .finalizeMethod();
```

Fixes #113513

Author: hekota

clang/include/clang/Basic/Builtins.td

@@ -4882,7 +4882,6 @@ def HLSLSaturate : LangBuiltin<"HLSL_LANG"> {
   let Prototype = "void(...)";
 }
 
-
 def HLSLSelect : LangBuiltin<"HLSL_LANG"> {
   let Spellings = ["__builtin_hlsl_select"];
   let Attributes = [NoThrow, Const];
@@ -4907,6 +4906,12 @@ def HLSLRadians : LangBuiltin<"HLSL_LANG"> {
   let Prototype = "void(...)";
 }
 
+def HLSLBufferUpdateCounter : LangBuiltin<"HLSL_LANG"> {
+  let Spellings = ["__builtin_hlsl_buffer_update_counter"];
+  let Attributes = [NoThrow];
+  let Prototype = "uint32_t(...)";
+}
+
 def HLSLSplitDouble: LangBuiltin<"HLSL_LANG"> {
   let Spellings = ["__builtin_hlsl_elementwise_splitdouble"];
   let Attributes = [NoThrow, Const];

clang/include/clang/Basic/DiagnosticSemaKinds.td

@@ -7287,6 +7287,8 @@ def err_typecheck_illegal_increment_decrement : Error<
   "cannot %select{decrement|increment}1 value of type %0">;
 def err_typecheck_expect_int : Error<
   "used type %0 where integer is required">;
+def err_typecheck_expect_hlsl_resource : Error<
+  "used type %0 where __hlsl_resource_t is required">;
 def err_typecheck_arithmetic_incomplete_or_sizeless_type : Error<
   "arithmetic on a pointer to %select{an incomplete|sizeless}0 type %1">;
 def err_typecheck_pointer_arith_function_type : Error<
@@ -12528,6 +12530,10 @@ def warn_attr_min_eq_max:  Warning<
 
 def err_hlsl_attribute_number_arguments_insufficient_shader_model: Error<
   "attribute %0 with %1 arguments requires shader model %2 or greater">;
+def err_hlsl_expect_arg_const_int_one_or_neg_one: Error<
+  "argument %0 must be constant integer 1 or -1">;
+def err_invalid_hlsl_resource_type: Error<
+  "invalid __hlsl_resource_t type attributes">;
 
 // Layout randomization diagnostics.
 def err_non_designated_init_used : Error<

clang/lib/CodeGen/CGBuiltin.cpp

@@ -19409,6 +19409,15 @@ case Builtin::BI__builtin_hlsl_elementwise_isinf: {
         CGM.getHLSLRuntime().getRadiansIntrinsic(), ArrayRef<Value *>{Op0},
         nullptr, "hlsl.radians");
   }
+  case Builtin::BI__builtin_hlsl_buffer_update_counter: {
+    Value *ResHandle = EmitScalarExpr(E->getArg(0));
+    Value *Offset = EmitScalarExpr(E->getArg(1));
+    Value *OffsetI8 = Builder.CreateIntCast(Offset, Int8Ty, true);
+    return Builder.CreateIntrinsic(
+        /*ReturnType=*/Offset->getType(),
+        CGM.getHLSLRuntime().getBufferUpdateCounterIntrinsic(),
+        ArrayRef<Value *>{ResHandle, OffsetI8}, nullptr);
+  }
   case Builtin::BI__builtin_hlsl_elementwise_splitdouble: {
 
     assert((E->getArg(0)->getType()->hasFloatingRepresentation() &&

clang/lib/CodeGen/CGHLSLRuntime.h

@@ -102,6 +102,7 @@ class CGHLSLRuntime {
   GENERATE_HLSL_INTRINSIC_FUNCTION(UClamp, uclamp)
 
   GENERATE_HLSL_INTRINSIC_FUNCTION(CreateHandleFromBinding, handle_fromBinding)
+  GENERATE_HLSL_INTRINSIC_FUNCTION(BufferUpdateCounter, bufferUpdateCounter)
 
   //===----------------------------------------------------------------------===//
   // End of reserved area for HLSL intrinsic getters.