[llvm-profgen] Ignore invalid perf line in LBR record

[wlei]

Summary

Similar to https://reviews.llvm.org/D109637, there is a whole invalid line of message in perfscript.

warning: Invalid address in LBR record at line 14118674: Processed 14138923 events and lost 1 chunks!
warning: Invalid address in LBR record at line 14118676: Check IO/CPU overload!

This only happened for LBR only perfscript, hybridperfscript have a check of " 0x" to make sure it's the LBR perf line.

[hoy]

lgtm.

Wondering for the two example warning lines, did the check against the first leading address before first LBR record pass?

[wenlei]

llvm/tools/llvm-profgen/PerfReader.cpp

435

We need to make sure this is a number?

Anything else we should check? Wondering if regex can make things easier and more robust.

[wlei]

In D110424#3020965, @hoy wrote:

lgtm.

Wondering for the two example warning lines, did the check against the first leading address before first LBR record pass?

yeah, just added the check.

llvm/tools/llvm-profgen/PerfReader.cpp

435

We need to make sure this is a number?

fixed

Anything else we should check?

with this.fix, it can pass our ads service perf.

Wondering if regex can make things easier and more robust.

Sounds good, I can have a try.

[wlei]

Updating D110424: [llvm-profgen] Ignore invalid perf line in LBR record

[wenlei]

lgtm, thanks.

llvm/test/tools/llvm-profgen/Inputs/noprobe.perfscript

+// Invalid perf line
            40062f 0x40062f/0x4005b0/P/-/-/9  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/6  0x40062f/0x4005b0/P/-/-/16  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/6  0x40062f/0x4005b0/P/-/-/6  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005c8/0x4005dc/P/-/-/8  0x40062f/0x4005b0/P/-/-/9  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/10  0x40062f/0x4005b0/P/-/-/14  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/7  0x40062f/0x4005b0/P/-/-/8  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005c8/0x4005dc/P/-/-/7  0x40062f/0x4005b0/P/-/-/15  0x400645/0x4005ff/P/-/-/1
            4005d7 0x4005d7/0x4005e5/P/-/-/8  0x40062f/0x4005b0/P/-/-/6  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/2  0x4005c8/0x4005dc/P/-/-/7  0x40062f/0x4005b0/P/-/-/11  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/8  0x40062f/0x4005b0/P/-/-/9  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/5  0x40062f/0x4005b0/P/-/-/11  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/2  0x4005c8/0x4005dc/P/-/-/7  0x40062f/0x4005b0/P/-/-/10  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/8  0x40062f/0x4005b0/P/-/-/9  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/13  0x40062f/0x4005b0/P/-/-/9
            4005c8 0x4005c8/0x4005dc/P/-/-/11  0x40062f/0x4005b0/P/-/-/8  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/5  0x40062f/0x4005b0/P/-/-/6  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/12  0x40062f/0x4005b0/P/-/-/6  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/2  0x4005c8/0x4005dc/P/-/-/7  0x40062f/0x4005b0/P/-/-/10  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/8  0x40062f/0x4005b0/P/-/-/9  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/12  0x40062f/0x4005b0/P/-/-/6  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/2  0x4005c8/0x4005dc/P/-/-/8  0x40062f/0x4005b0/P/-/-/8

llvm/tools/llvm-profgen/PerfReader.cpp

 bool PerfReaderBase::extractLBRStack(TraceStream &TraceIt,
                                      SmallVectorImpl<LBREntry> &LBRStack) {
   // The raw format of LBR stack is like:
   // 0x4005c8/0x4005dc/P/-/-/0 0x40062f/0x4005b0/P/-/-/0 ...
   //                           ... 0x4005c8/0x4005dc/P/-/-/0
   // It's in FIFO order and seperated by whitespace.
   SmallVector<StringRef, 32> Records;
   TraceIt.getCurrentLine().split(Records, " ", -1, false);
+  auto WarnInvalidLBR = [](TraceStream &TraceIt) {
+    WithColor::warning() << "Invalid address in LBR record at line "
+                         << TraceIt.getLineNumber() << ": "
+                         << TraceIt.getCurrentLine() << "\n";
+  };
 
   // Skip the leading instruction pointer.
   size_t Index = 0;
+  uint64_t LeadingAddr;
   if (!Records.empty() && Records[0].find('/') == StringRef::npos) {
+    if (Records[0].getAsInteger(16, LeadingAddr)) {
+      WarnInvalidLBR(TraceIt);
+      TraceIt.advance();
+      return false;
+    }
     Index = 1;
   }
   // Now extract LBR samples - note that we do not reverse the
   // LBR entry order so we can unwind the sample stack as we walk
   // through LBR entries.
   uint64_t PrevTrDst = 0;
 
   while (Index < Records.size()) {
     auto &Token = Records[Index++];
     if (Token.size() == 0)
       continue;
 
     SmallVector<StringRef, 8> Addresses;
     Token.split(Addresses, "/");
     uint64_t Src;
     uint64_t Dst;
 
     // Stop at broken LBR records.
-    if (Addresses[0].substr(2).getAsInteger(16, Src) ||
+    if (Addresses.size() < 2 || Addresses[0].substr(2).getAsInteger(16, Src) ||
         Addresses[1].substr(2).getAsInteger(16, Dst)) {
-      WithColor::warning() << "Invalid address in LBR record at line "
-                           << TraceIt.getLineNumber() << ": "
-                           << TraceIt.getCurrentLine() << "\n";
+      WarnInvalidLBR(TraceIt);
       break;
     }
 
     bool SrcIsInternal = Binary->addressIsCode(Src);
     bool DstIsInternal = Binary->addressIsCode(Dst);
     bool IsExternal = !SrcIsInternal && !DstIsInternal;
     bool IsIncoming = !SrcIsInternal && DstIsInternal;
     bool IsOutgoing = SrcIsInternal && !DstIsInternal;