diff --git a/llvm/test/tools/llvm-profgen/Inputs/recursion-compression-pseudoprobe-nommap.perfscript b/llvm/test/tools/llvm-profgen/Inputs/recursion-compression-pseudoprobe-nommap.perfscript
new file mode 100644
--- /dev/null
+++ b/llvm/test/tools/llvm-profgen/Inputs/recursion-compression-pseudoprobe-nommap.perfscript
@@ -0,0 +1,21 @@
+	          2017db
+	          2017ba
+	          2017e5
+	          2017ba
+	          2017e5
+	          2017d9
+	          2017ba
+	          2017b0
+	          2017b0
+	          2017b0
+	          2017b0
+	          2017b0
+	          2017b0
+	          2017b0
+	          2017b0
+	          2017e5
+	          2017d9
+	          201847
+	    7fcb072a67c3
+	5541f689495641d7
+ 0x2017cd/0x2017db/P/-/-/0  0x2017b5/0x2017c0/P/-/-/0  0x2017a7/0x2017b2/P/-/-/0  0x2017e0/0x2017a0/P/-/-/0  0x2017cd/0x2017db/P/-/-/0  0x2017b5/0x2017c0/P/-/-/0  0x2017a7/0x2017b2/P/-/-/0  0x2017e0/0x2017a0/P/-/-/0  0x2017cd/0x2017db/P/-/-/0  0x2017d4/0x2017c0/P/-/-/0  0x2017b5/0x2017c0/P/-/-/0  0x2017a7/0x2017b2/P/-/-/0  0x2017ab/0x2017a0/P/-/-/0  0x2017ab/0x2017a0/P/-/-/0  0x2017ab/0x2017a0/P/-/-/0  0x2017ab/0x2017a0/P/-/-/0
diff --git a/llvm/test/tools/llvm-profgen/recursion-compression-pseudoprobe.test b/llvm/test/tools/llvm-profgen/recursion-compression-pseudoprobe.test
--- a/llvm/test/tools/llvm-profgen/recursion-compression-pseudoprobe.test
+++ b/llvm/test/tools/llvm-profgen/recursion-compression-pseudoprobe.test
@@ -3,6 +3,9 @@
 ; RUN: FileCheck %s --input-file %t -check-prefix=CHECK-UNCOMPRESS
 ; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/recursion-compression-pseudoprobe.perfscript --binary=%S/Inputs/recursion-compression-pseudoprobe.perfbin --output=%t --show-unwinder-output --profile-summary-cold-count=0 | FileCheck %s --check-prefix=CHECK-UNWINDER
 ; RUN: FileCheck %s --input-file %t
+; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/recursion-compression-pseudoprobe-nommap.perfscript --binary=%S/Inputs/recursion-compression-pseudoprobe.perfbin --output=%t --show-unwinder-output --profile-summary-cold-count=0 | FileCheck %s --check-prefix=CHECK-UNWINDER
+; RUN: FileCheck %s --input-file %t
+
 
 ; CHECK-UNCOMPRESS: [main:2 @ foo:5 @ fa:8 @ fa:7 @ fb:5 @ fb:5 @ fb:5 @ fb:5 @ fb:5 @ fb:5 @ fb:5 @ fb:5 @ fb:6 @ fa:8 @ fa:7 @ fb:6 @ fa]:4:1
 ; CHECK-UNCOMPRESS:  1: 1
diff --git a/llvm/tools/llvm-profgen/PerfReader.h b/llvm/tools/llvm-profgen/PerfReader.h
--- a/llvm/tools/llvm-profgen/PerfReader.h
+++ b/llvm/tools/llvm-profgen/PerfReader.h
@@ -653,6 +653,10 @@
   // Samples with the repeating time generated by the perf reader
   AggregatedCounter AggregatedSamples;
   PerfScriptType PerfType = PERF_UNKNOWN;
+
+  // Use to check and warn whether we have met a mmap event before parsing a
+  // sample
+  bool EventSeen = false;
 };
 
 /*
diff --git a/llvm/tools/llvm-profgen/PerfReader.cpp b/llvm/tools/llvm-profgen/PerfReader.cpp
--- a/llvm/tools/llvm-profgen/PerfReader.cpp
+++ b/llvm/tools/llvm-profgen/PerfReader.cpp
@@ -317,7 +317,13 @@
     exitWithError(ErrorMsg);
   }
 
-  return Ret.first->second;
+  // Initialize the base address to preferred address.
+  ProfiledBinary &B = Ret.first->second;
+  uint64_t PreferredAddr = B.getPreferredBaseAddress();
+  AddrToBinaryMap[PreferredAddr] = &B;
+  B.setBaseAddress(PreferredAddr);
+
+  return B;
 }
 
 void PerfReaderBase::updateBinaryAddress(const MMapEvent &Event) {
@@ -641,6 +647,13 @@
       // Record samples by aggregation
       Sample->genHashCode();
       AggregatedSamples[Hashable<PerfSample>(Sample)]++;
+      if (!EventSeen) {
+        WithColor::warning()
+            << "No corresponding mmap event is matched, will use preferred "
+               "address as the base loading address!\n";
+        // Avoid redundant warning, only warn at the first unmatched sample.
+        EventSeen = true;
+      }
     }
   } else {
     // LBR sample is encoded in single line after stack sample
@@ -649,6 +662,7 @@
 }
 
 void PerfReaderBase::parseMMap2Event(TraceStream &TraceIt) {
+  EventSeen = true;
   // Parse a line like:
   //  PERF_RECORD_MMAP2 2113428/2113428: [0x7fd4efb57000(0x204000) @ 0
   //  08:04 19532229 3585508847]: r-xp /usr/lib64/libdl-2.17.so
@@ -727,8 +741,10 @@
 void PerfReaderBase::parsePerfTraces(
     cl::list<std::string> &PerfTraceFilenames) {
   // Parse perf traces and do aggregation.
-  for (auto Filename : PerfTraceFilenames)
+  for (auto Filename : PerfTraceFilenames) {
+    EventSeen = false;
     parseAndAggregateTrace(Filename);
+  }
 
   generateRawProfile();
 }