[libomptarget][nfc] Accept callable for hsa iterate_symbols

[JonChesterfield]

Summary

[libomptarget][nfc] Accept callable for hsa iterate_symbols
Candidate refactor to simplify D102692

[JonChesterfield]

• drop dead executable argument

[JonChesterfield]

openmp/libomptarget/plugins/amdgpu/impl/system.cpp

1012–1013

This change means populate_InfoTables can have a different type from the HSA callback, e.g. could take pointers to infotables directly

1242–1243

...because there can now be a capturing lambda to do the impedance mismatch

[pdhaliwal]

Looks good. My opinion is that we should keep these wrappers in a separate file, but that could be a later patch.

[JonChesterfield]

In D103030#2778888, @pdhaliwal wrote:

Looks good. My opinion is that we should keep these wrappers in a separate file, but that could be a later patch.

Agreed, got stuck on picking a name and decided it was more important to get the diff up quickly.

There are a few things being considered for hsa:

• easier API via C++ wrapper
• wrapping calls in optional profiling collection
• dlopen hsa instead of link, for building llvm on systems without hsa installed

They're all somewhat related. I haven't put enough thought into the design space yet.

openmp/libomptarget/plugins/amdgpu/impl/system.cpp

 /*===--------------------------------------------------------------------------
  *              ATMI (Asynchronous Task and Memory Interface)
  *
  * This file is distributed under the MIT License. See LICENSE.txt for details.
  *===------------------------------------------------------------------------*/
 #include <gelf.h>
 #include <libelf.h>
 
 #include <cassert>
 #include <cstdarg>
 #include <fstream>
 #include <iomanip>
 #include <iostream>
 #include <set>
 #include <string>
 
 #include "internal.h"
 #include "machine.h"
 #include "rt.h"
 
 #include "msgpack.h"
 
+namespace hsa {
+// Wrap HSA iterate API in a shim that allows passing general callables
+template <typename C>
+hsa_status_t executable_iterate_symbols(hsa_executable_t executable, C cb) {
+  auto L = [](hsa_executable_t executable, hsa_executable_symbol_t symbol,
+              void *data) -> hsa_status_t {
+    C *unwrapped = static_cast<C *>(data);
+    return (*unwrapped)(executable, symbol);
+  };
+  return hsa_executable_iterate_symbols(executable, L,
+                                        static_cast<void *>(&cb));
+}
+} // namespace hsa
+
 typedef unsigned char *address;
 /*
  * Note descriptors.
  */
 typedef struct {
   uint32_t n_namesz; /* Length of note's name. */
   uint32_t n_descsz; /* Length of note's value. */
   uint32_t n_type;   /* Type of note. */
DEBUG_PRINT("[%s: kernarg seg size] (%lu --> %u)\n", kernelName.c_str(),
                 kernel_segment_size, info.kernel_segment_size);
 
     // kernel received, now add it to the kernel info table
     KernelInfoTable[gpu][kernelName] = info;
   }
 
   return HSA_STATUS_SUCCESS;
 }
 
-static hsa_status_t populate_InfoTables(hsa_executable_t executable,
-                                        hsa_executable_symbol_t symbol,
-                                        void *data) {
-  int gpu = *static_cast<int *>(data);
+static hsa_status_t populate_InfoTables(hsa_executable_symbol_t symbol,
+                                        int gpu) {
   hsa_symbol_kind_t type;
 
   uint32_t name_length;
   hsa_status_t err;
   err = hsa_executable_symbol_get_info(symbol, HSA_EXECUTABLE_SYMBOL_INFO_TYPE,
                                        &type);
   if (err != HSA_STATUS_SUCCESS) {
     printf("[%s:%d] %s failed: %s\n", __FILE__, __LINE__,
atmi_status_t Runtime::RegisterModuleFromMemory(
   if (module_load_success) {
     /* Freeze the executable; it can now be queried for symbols.  */
     err = hsa_executable_freeze(executable, "");
     if (err != HSA_STATUS_SUCCESS) {
       printf("[%s:%d] %s failed: %s\n", __FILE__, __LINE__,
              "Freeze the executable", get_error_string(err));
       return ATMI_STATUS_ERROR;
     }
 
-    err = hsa_executable_iterate_symbols(executable, populate_InfoTables,
-                                         static_cast<void *>(&gpu));
+    err = hsa::executable_iterate_symbols(
+        executable,
+        [&](hsa_executable_t, hsa_executable_symbol_t symbol) -> hsa_status_t {
+          return populate_InfoTables(symbol, gpu);
+        });
+
     if (err != HSA_STATUS_SUCCESS) {
       printf("[%s:%d] %s failed: %s\n", __FILE__, __LINE__,
              "Iterating over symbols for execuatable", get_error_string(err));
       return ATMI_STATUS_ERROR;
     }
 
     // save the executable and destroy during finalize
     HSAExecutables.push_back(executable);
     return ATMI_STATUS_SUCCESS;
   } else {
     return ATMI_STATUS_ERROR;
   }
 }
 
 } // namespace core