[wasm] Replace FunctionSizeBytes histograms with HugeFunctionSizeBytes

We only care about huge functions (>100kB) as they can cause extended
compilation times and OOM situations. These are difficult to see in the
existing histogram as they only account for a tiny fraction of functions.
We therefore introduce a new counter that only covers those functions
and remove the other histogram.

Bug: chromium:1222273
Change-Id: I72fcec3fda5a358de6e29eb78d1fcf40059fb6c8
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3008646Reviewed-by: Clemens Backes <clemensb@chromium.org>
Commit-Queue: Emanuel Ziegler <ecmziegler@chromium.org>
Cr-Commit-Position: refs/heads/master@{#75594}

src/logging/counters-definitions.h

@@ -45,8 +45,10 @@ namespace internal {
   HR(array_buffer_new_size_failures, V8.ArrayBufferNewSizeFailures, 0, 4096,   \
      13)                                                                       \
   HR(shared_array_allocations, V8.SharedArrayAllocationSizes, 0, 4096, 13)     \
-  HR(wasm_asm_function_size_bytes, V8.WasmFunctionSizeBytes.asm, 1, GB, 51)    \
-  HR(wasm_wasm_function_size_bytes, V8.WasmFunctionSizeBytes.wasm, 1, GB, 51)  \
+  HR(wasm_asm_huge_function_size_bytes, V8.WasmHugeFunctionSizeBytes.asm,      \
+     100 * KB, GB, 51)                                                         \
+  HR(wasm_wasm_huge_function_size_bytes, V8.WasmHugeFunctionSizeBytes.wasm,    \
+     100 * KB, GB, 51)                                                         \
   HR(wasm_asm_module_size_bytes, V8.WasmModuleSizeBytes.asm, 1, GB, 51)        \
   HR(wasm_wasm_module_size_bytes, V8.WasmModuleSizeBytes.wasm, 1, GB, 51)      \
   HR(wasm_asm_min_mem_pages_count, V8.WasmMinMemPagesCount.asm, 1, 2 << 16,    \

src/wasm/function-compiler.cc

@@ -77,10 +77,12 @@ WasmCompilationResult WasmCompilationUnit::ExecuteFunctionCompilation(
 
   base::Optional<TimedHistogramScope> wasm_compile_function_time_scope;
   if (counters) {
-    auto size_histogram = SELECT_WASM_COUNTER(counters, env->module->origin,
-                                              wasm, function_size_bytes);
-    size_histogram->AddSample(
-        static_cast<int>(func_body.end - func_body.start));
+    if ((func_body.end - func_body.start) >= 100 * KB) {
+      auto huge_size_histogram = SELECT_WASM_COUNTER(
+          counters, env->module->origin, wasm, huge_function_size_bytes);
+      huge_size_histogram->AddSample(
+          static_cast<int>(func_body.end - func_body.start));
+    }
     auto timed_histogram = SELECT_WASM_COUNTER(counters, env->module->origin,
                                                wasm_compile, function_time);
     wasm_compile_function_time_scope.emplace(timed_histogram);

src/wasm/module-decoder.cc

@@ -2173,10 +2173,6 @@ FunctionResult DecodeWasmFunctionForTesting(
     const byte* function_end, Counters* counters) {
   size_t size = function_end - function_start;
   CHECK_LE(function_start, function_end);
-  auto size_histogram =
-      SELECT_WASM_COUNTER(counters, module->origin, wasm, function_size_bytes);
-  // TODO(bradnelson): Improve histogram handling of ptrdiff_t.
-  size_histogram->AddSample(static_cast<int>(size));
   if (size > kV8MaxWasmFunctionSize) {
     return FunctionResult{WasmError{0,
                                     "size > maximum function size (%zu): %zu",