[libc] Test the RPC interface with multiple blocks

[jhuber6]

Summary

The RPC interface can support multiple independent clients. This support
currently only supports many single-thread warps / workgroups
coordinating over a single lock. This patch uses the support added in
the previous patch to test the RPC interface with multiple blocks.

Note that this does not work with multiple threads currently because of
the effect of warps / workgroups executing in lockstep incorrectly. This
will be added later.

Depends on D148485

[jhuber6]

Update to use the GPU utility library.

[sivachandra]

libc/cmake/modules/LLVMLibCTestRules.cmake

424

Add usage documentation under line 399.

libc/cmake/modules/LLVMLibCTestRules.cmake

function(add_integration_test test_name)
   if(NOT (${LIBC_TARGET_OS} IN_LIST supported_targets))
     message(STATUS "Skipping ${fq_target_name} as it is not available on ${LIBC_TARGET_OS}.")
     return()
   endif()
   cmake_parse_arguments(
     "INTEGRATION_TEST"
     "" # No optional arguments
     "SUITE" # Single value arguments
-    "SRCS;HDRS;DEPENDS;ARGS;ENV;COMPILE_OPTIONS" # Multi-value arguments
+    "SRCS;HDRS;DEPENDS;ARGS;ENV;COMPILE_OPTIONS;LOADER_ARGS" # Multi-value arguments
     ${ARGN}
   )
 
   if(NOT INTEGRATION_TEST_SUITE)
     message(FATAL_ERROR "SUITE not specified for ${fq_target_name}")
   endif()
   if(NOT INTEGRATION_TEST_SRCS)
     message(FATAL_ERROR "The SRCS list for add_integration_test is missing.")
if(TARGET libc.utils.gpu.loader)
     add_dependencies(${fq_build_target_name} libc.utils.gpu.loader)
     get_target_property(gpu_loader_exe libc.utils.gpu.loader "EXECUTABLE")
   endif()
 
   add_custom_target(
     ${fq_target_name}
     COMMAND ${INTEGRATION_TEST_ENV}
             $<$<BOOL:${LIBC_TARGET_ARCHITECTURE_IS_GPU}>:${gpu_loader_exe}>
+            ${INTEGRATION_TEST_LOADER_ARGS}
             $<TARGET_FILE:${fq_build_target_name}> ${INTEGRATION_TEST_ARGS}
     COMMENT "Running integration test ${fq_target_name}"
   )
   add_dependencies(${INTEGRATION_TEST_SUITE} ${fq_target_name})
 endfunction(add_integration_test)

libc/test/integration/startup/gpu/CMakeLists.txt

 
 add_integration_test(
   startup_rpc_test
   SUITE libc-startup-tests
   SRCS
     rpc_test.cpp
   DEPENDS
     libc.src.__support.RPC.rpc_client
+    libc.src.__support.GPU.utils
+  LOADER_ARGS
+    --blocks 16
+    --threads 1
 )

libc/test/integration/startup/gpu/rpc_test.cpp

 //===-- Loader test to check the RPC interface with the loader ------------===//
 //
 // 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
 //
 //===----------------------------------------------------------------------===//
 
+#include "src/__support/GPU/utils.h"
 #include "src/__support/RPC/rpc_client.h"
 #include "test/IntegrationTest/test.h"
 
 using namespace __llvm_libc;
 
 static void test_add_simple() {
-  constexpr int num_additions = 10000;
+  uint32_t num_additions = 1000 + 10 * get_block_id_x();
   uint64_t cnt = 0;
-  for (int i = 0; i < num_additions; ++i) {
+  for (uint32_t i = 0; i < num_additions; ++i) {
     rpc::Port port = rpc::client.open(rpc::TEST_INCREMENT);
     port.send_and_recv(
         [=](rpc::Buffer *buffer) {
           reinterpret_cast<uint64_t *>(buffer->data)[0] = cnt;
         },
         [&](rpc::Buffer *buffer) {
           cnt = reinterpret_cast<uint64_t *>(buffer->data)[0];
         });
     port.close();
   }
   ASSERT_TRUE(cnt == num_additions && "Incorrect sum");
 }
 
 TEST_MAIN(int argc, char **argv, char **envp) {
   test_add_simple();
+
   return 0;
 }