[benchmark] Fix static initialization bug in bm_huffman_decode (#32245)

* [benchmark] Fix static initialization bug in bm_huffman_decode

* fix performance

test/cpp/microbenchmarks/bm_huffman_decode.cc

@@ -19,34 +19,38 @@
 
 #include "src/core/ext/transport/chttp2/transport/bin_encoder.h"
 #include "src/core/ext/transport/chttp2/transport/decode_huff.h"
+#include "src/core/lib/gprpp/no_destruct.h"
 #include "src/core/lib/slice/slice.h"
 #include "test/core/util/test_config.h"
 
-static const std::vector<uint8_t>* kInput = [] {
+const std::vector<uint8_t>* Input() {
-  std::vector<uint8_t> v;
+  static const grpc_core::NoDestruct<std::vector<uint8_t>> v([]() {
-  std::mt19937 rd(0);
+    std::vector<uint8_t> v;
-  std::uniform_int_distribution<> dist_ty(0, 100);
+    std::mt19937 rd(0);
-  std::uniform_int_distribution<> dist_byte(0, 255);
+    std::uniform_int_distribution<> dist_ty(0, 100);
-  std::uniform_int_distribution<> dist_normal(32, 126);
+    std::uniform_int_distribution<> dist_byte(0, 255);
-  for (int i = 0; i < 1024 * 1024; i++) {
+    std::uniform_int_distribution<> dist_normal(32, 126);
-    if (dist_ty(rd) == 1) {
+    for (int i = 0; i < 1024 * 1024; i++) {
-      v.push_back(dist_byte(rd));
+      if (dist_ty(rd) == 1) {
-    } else {
+        v.push_back(dist_byte(rd));
-      v.push_back(dist_normal(rd));
+      } else {
+        v.push_back(dist_normal(rd));
+      }
     }
-  }
+    grpc_core::Slice s = grpc_core::Slice::FromCopiedBuffer(v);
-  grpc_core::Slice s = grpc_core::Slice::FromCopiedBuffer(v);
+    grpc_core::Slice c(grpc_chttp2_huffman_compress(s.c_slice()));
-  grpc_core::Slice c(grpc_chttp2_huffman_compress(s.c_slice()));
+    return std::vector<uint8_t>(c.begin(), c.end());
-  return new std::vector<uint8_t>(c.begin(), c.end());
+  }());
-}();
+  return v.get();
+}
 
 static void BM_Decode(benchmark::State& state) {
   std::vector<uint8_t> output;
   auto add = [&output](uint8_t c) { output.push_back(c); };
   for (auto _ : state) {
     output.clear();
-    grpc_core::HuffDecoder<decltype(add)>(add, kInput->data(),
+    grpc_core::HuffDecoder<decltype(add)>(add, Input()->data(),
-                                          kInput->data() + kInput->size())
+                                          Input()->data() + Input()->size())
         .Run();
   }
 }
@@ -446,7 +450,7 @@ static void BM_LegacyDecode(benchmark::State& state) {
   for (auto _ : state) {
     output.clear();
     decode_state = 0;
-    for (auto c : *kInput) {
+    for (auto c : *Input()) {
       nibble(c >> 4);
       nibble(c & 0xf);
     }
@@ -463,6 +467,7 @@ void RunTheBenchmarksNamespaced() { RunSpecifiedBenchmarks(); }
 int main(int argc, char** argv) {
   grpc::testing::TestEnvironment env(&argc, argv);
   benchmark::Initialize(&argc, argv);
+  Input();  // Force initialization of input data.
   benchmark::RunTheBenchmarksNamespaced();
   return 0;
 }