[llvm] [Offload] Add GenericProfilerTy abstraction and APITypes extensions (upstream OMPT device tracing 1/n) (PR #214340)

[Alex Duran via llvm-commits]

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+//===- GenericProfiler.h - GenericProfiler interface for use in Plugins ---===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// The GenericProfiler interface allows to implement profiler logic for various
+// backends, such as OMPT or other tracing mechanisms.
+// This enables the plugins to be agnostic of the actual high-level language
+// that is implemented.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef OFFLOAD_PLUGINS_NEXTGEN_COMMON_INCLUDE_GENERICPROFILER_H
+#define OFFLOAD_PLUGINS_NEXTGEN_COMMON_INCLUDE_GENERICPROFILER_H
+
+#include "Shared/APITypes.h"
+
+#include <cstdint>
+#include <functional>
+#include <tuple>
+
+namespace llvm {
+namespace omp {
+namespace target {
+namespace plugin {
+
+struct GenericDeviceTy;
+struct GenericPluginTy;
+class GenericProfilerTy;
+
+template <typename FunT, typename... ArgsT, size_t... IdxSequence>
+void callViaIndexSeq(FunT F, GenericProfilerTy *P, uint64_t StartNanos,
+                     uint64_t EndNanos, std::tuple<ArgsT...> Args,
+                     std::index_sequence<IdxSequence...>) {
+  F(P, StartNanos, EndNanos, std::get<IdxSequence>(Args)...);
+}
+
+template <typename FunT, typename... ArgsT>
+void callViaUnpack(FunT F, GenericProfilerTy *P, uint64_t StartNanos,
+                   uint64_t EndNanos, std::tuple<ArgsT...> Tup) {
+  callViaIndexSeq(F, P, StartNanos, EndNanos, Tup,
+                  std::index_sequence_for<ArgsT...>{});
+}
+
+/// Abstraction layer to implement different profiler backends.
+///
+/// The plugins call into the GenericProfilerTy to handle the specific events
+/// with whatever specific backend was instantiated. For now, the supported
+/// backends are limited to an OMPT implementation.
+class GenericProfilerTy {
+public:
+  GenericProfilerTy() = default;
+  virtual ~GenericProfilerTy() = default;
+
+  /// Obtain a pointer to profiler-specific data, if any.
+  virtual void *getProfilerSpecificData() { return nullptr; }
+
+  virtual bool isProfilingEnabled() { return false; }
+
+  /// Set the factors which are used to interpolate the device clock compared to
+  /// the host clock. This follows a simple linear interpolation: Slope * <time>
+  /// + Offset.
+  void setTimeConversionFactors(double Slope, double Offset) {
+    HostToDeviceSlope = Slope;
+    HostToDeviceOffset = Offset;
+    setTimeConversionFactorsImpl(HostToDeviceSlope, HostToDeviceOffset);
+  }
+
+  /// Hook that is called when the plugin is initialized.
+  virtual void handleInit(GenericDeviceTy *Device, GenericPluginTy *Plugin) {}
+
+  /// Hook that is called when the plugin is de-initialized.
+  virtual void handleDeinit(GenericDeviceTy *Device, GenericPluginTy *Plugin) {}
+
+  /// Hook that is called when the device image is loaded.
+  virtual void handleLoadBinary(GenericDeviceTy *Device,
+                                GenericPluginTy *Plugin,
+                                const StringRef InputTgtImage) {}
+
+  /// Hook that is called when memory is allocated on the device.
+  virtual void handleDataAlloc(uint64_t StartNanos, uint64_t EndNanos,
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adurang wrote:

Ah, I see about the timestamps. Got it.

For Data, the thing I can't quite get is how that is gonna be obtained. So far what I've seen (but maybe there's something else in the larger changes) is that the tool data is associated with the Async object but these routines don't have any such object to get the data from. 

https://github.com/llvm/llvm-project/pull/214340