[libc] [gpu] Change Time To Be Per Iteration

[jameshu15869]

Previously, the time field was the total time take to run all iterations of the benchmark. This PR changes the value displayed to be the average time take by each iteration.

[llvmbot]

@llvm/pr-subscribers-libc

Author: None (jameshu15869)

Changes

Previously, the time field was the total time take to run all iterations of the benchmark. This PR changes the value displayed to be the average time take by each iteration.

---

Full diff: https://github.com/llvm/llvm-project/pull/101919.diff

1 Files Affected:

• (modified) libc/benchmarks/gpu/LibcGpuBenchmark.cpp (+5-5)

diff --git a/libc/benchmarks/gpu/LibcGpuBenchmark.cpp b/libc/benchmarks/gpu/LibcGpuBenchmark.cpp
index a5dbc62a2087b..28235cf137c18 100644
--- a/libc/benchmarks/gpu/LibcGpuBenchmark.cpp
+++ b/libc/benchmarks/gpu/LibcGpuBenchmark.cpp
@@ -115,7 +115,7 @@ void print_results(Benchmark *b) {
   cpp::atomic_thread_fence(cpp::MemoryOrder::RELEASE);
 
   LIBC_NAMESPACE::printf(
-      "%-20s |%8ld |%8ld |%8ld |%11d |%9ld %2s |%9ld |%9d |\n",
+      "%-20s |%8ld |%8ld |%8ld |%11d |%14ld %2s |%9ld |%9d |\n",
       b->get_test_name().data(), result.cycles, result.min, result.max,
       result.total_iterations, result.total_time, time_unit,
       static_cast<uint64_t>(result.standard_deviation), num_threads);
@@ -126,9 +126,9 @@ void print_header() {
   LIBC_NAMESPACE::printf("Running Suite: %-10s\n",
                          benchmarks[0]->get_suite_name().data());
   LIBC_NAMESPACE::printf("%s", RESET);
-  LIBC_NAMESPACE::printf("Benchmark            |  Cycles |     Min |     Max | "
-                         "Iterations |        "
-                         "Time |   Stddev |  Threads |\n");
+  LIBC_NAMESPACE::printf(
+      "Benchmark            |  Cycles |     Min |     Max | "
+      "Iterations | Time / Iteration |   Stddev |  Threads |\n");
   LIBC_NAMESPACE::printf(
       "---------------------------------------------------------------------"
       "--------------------------------\n");
@@ -222,7 +222,7 @@ BenchmarkResult benchmark(const BenchmarkOptions &options,
   result.max = max;
   result.samples = samples;
   result.total_iterations = total_iterations;
-  result.total_time = total_time;
+  result.total_time = total_time / total_iterations;
   return result;
 };