[llvm] [BOLT] Make memory profile parsing optional (PR #129585)

[Amir Ayupov via llvm-commits]

https://github.com/aaupov updated https://github.com/llvm/llvm-project/pull/129585

>From 868e791ff4c45cc3d3270a4778d5b76c61c8c28b Mon Sep 17 00:00:00 2001
From: Amir Ayupov <aaupov at fb.com>
Date: Mon, 3 Mar 2025 12:20:29 -0800
Subject: [PATCH] =?UTF-8?q?[=F0=9D=98=80=F0=9D=97=BD=F0=9D=97=BF]=20initia?=
 =?UTF-8?q?l=20version?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Created using spr 1.3.4
---
 bolt/lib/Profile/DataAggregator.cpp | 49 +++++++++++++++++------------
 1 file changed, 29 insertions(+), 20 deletions(-)

diff --git a/bolt/lib/Profile/DataAggregator.cpp b/bolt/lib/Profile/DataAggregator.cpp
index d20626bd5062f..909ec32477468 100644
--- a/bolt/lib/Profile/DataAggregator.cpp
+++ b/bolt/lib/Profile/DataAggregator.cpp
@@ -61,6 +61,12 @@ FilterMemProfile("filter-mem-profile",
   cl::init(true),
   cl::cat(AggregatorCategory));
 
+static cl::opt<bool> ParseMemProfile(
+    "parse-mem-profile",
+    cl::desc("enable memory profile parsing if it's present in the input data, "
+             "on by default unless `--itrace` is set."),
+    cl::init(true), cl::cat(AggregatorCategory));
+
 static cl::opt<unsigned long long>
 FilterPID("pid",
   cl::desc("only use samples from process with specified PID"),
@@ -177,6 +183,10 @@ void DataAggregator::start() {
                       "script -F pid,event,ip",
                       /*Wait = */false);
   } else if (!opts::ITraceAggregation.empty()) {
+    // Disable parsing memory profile from trace data, unless requested by user.
+    if (!opts::ParseMemProfile.getNumOccurrences())
+      opts::ParseMemProfile = false;
+
     std::string ItracePerfScriptArgs = llvm::formatv(
         "script -F pid,brstack --itrace={0}", opts::ITraceAggregation);
     launchPerfProcess("branch events with itrace", MainEventsPPI,
@@ -187,12 +197,9 @@ void DataAggregator::start() {
                       /*Wait = */ false);
   }
 
-  // Note: we launch script for mem events regardless of the option, as the
-  //       command fails fairly fast if mem events were not collected.
-  launchPerfProcess("mem events",
-                    MemEventsPPI,
-                    "script -F pid,event,addr,ip",
-                    /*Wait = */false);
+  if (opts::ParseMemProfile)
+    launchPerfProcess("mem events", MemEventsPPI, "script -F pid,event,addr,ip",
+                      /*Wait = */ false);
 
   launchPerfProcess("process events", MMapEventsPPI,
                     "script --show-mmap-events --no-itrace",
@@ -213,7 +220,8 @@ void DataAggregator::abort() {
   sys::Wait(TaskEventsPPI.PI, 1, &Error);
   sys::Wait(MMapEventsPPI.PI, 1, &Error);
   sys::Wait(MainEventsPPI.PI, 1, &Error);
-  sys::Wait(MemEventsPPI.PI, 1, &Error);
+  if (opts::ParseMemProfile)
+    sys::Wait(MemEventsPPI.PI, 1, &Error);
 
   deleteTempFiles();
 
@@ -464,13 +472,6 @@ Error DataAggregator::preprocessProfile(BinaryContext &BC) {
     exit(1);
   };
 
-  auto MemEventsErrorCallback = [&](int ReturnCode, StringRef ErrBuf) {
-    Regex NoData("Samples for '.*' event do not have ADDR attribute set. "
-                 "Cannot print 'addr' field.");
-    if (!NoData.match(ErrBuf))
-      ErrorCallback(ReturnCode, ErrBuf);
-  };
-
   if (BC.IsLinuxKernel) {
     // Current MMap parsing logic does not work with linux kernel.
     // MMap entries for linux kernel uses PERF_RECORD_MMAP
@@ -511,13 +512,21 @@ Error DataAggregator::preprocessProfile(BinaryContext &BC) {
       (opts::BasicAggregation && parseBasicEvents()))
     errs() << "PERF2BOLT: failed to parse samples\n";
 
-  // Special handling for memory events
-  if (prepareToParse("mem events", MemEventsPPI, MemEventsErrorCallback))
-    return Error::success();
+  if (opts::ParseMemProfile) {
+    auto MemEventsErrorCallback = [&](int ReturnCode, StringRef ErrBuf) {
+      Regex NoData("Samples for '.*' event do not have ADDR attribute set. "
+                   "Cannot print 'addr' field.");
+      if (!NoData.match(ErrBuf))
+        ErrorCallback(ReturnCode, ErrBuf);
+    };
 
-  if (const std::error_code EC = parseMemEvents())
-    errs() << "PERF2BOLT: failed to parse memory events: " << EC.message()
-           << '\n';
+    if (prepareToParse("mem events", MemEventsPPI, MemEventsErrorCallback))
+      return Error::success();
+
+    if (const std::error_code EC = parseMemEvents())
+      errs() << "PERF2BOLT: failed to parse memory events: " << EC.message()
+             << '\n';
+  }
 
   deleteTempFiles();