diff --git a/bolt/src/BinaryContext.cpp b/bolt/src/BinaryContext.cpp
index ab32825554c7..329dabb52d96 100644
--- a/bolt/src/BinaryContext.cpp
+++ b/bolt/src/BinaryContext.cpp
@@ -685,11 +685,9 @@ bool BinaryContext::hasValidCodePadding(const BinaryFunction &BF) {
            << Twine::utohexstr(BF.getAddress() + BF.getSize())
            << " starting at offset "
            << (Offset - BF.getSize()) << " in function "
-           << BF << '\n';
-    for (auto I = BF.getSize(); I < BF.getMaxSize(); ++I) {
-      errs() << format("%.2x ", (*FunctionData)[I]);
-    }
-    errs() << '\n';
+           << BF << '\n'
+           << FunctionData->slice(BF.getSize(), BF.getMaxSize() - BF.getSize())
+           << '\n';
   }
 
   return false;
diff --git a/bolt/src/BinaryContext.h b/bolt/src/BinaryContext.h
index ae5c9c34aff0..0d9388a01e04 100644
--- a/bolt/src/BinaryContext.h
+++ b/bolt/src/BinaryContext.h
@@ -20,6 +20,7 @@
 #include "JumpTable.h"
 #include "MCPlusBuilder.h"
 #include "llvm/ADT/iterator.h"
+#include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/Triple.h"
 #include "llvm/DebugInfo/DWARF/DWARFCompileUnit.h"
 #include "llvm/DebugInfo/DWARF/DWARFContext.h"
@@ -46,6 +47,7 @@
 #include <shared_mutex>
 #include <string>
 #include <system_error>
+#include <type_traits>
 #include <unordered_map>
 #include <vector>
 
@@ -1039,6 +1041,18 @@ public:
   }
 };
 
+template <typename T,
+          typename = std::enable_if_t<sizeof(T) == 1> >
+inline raw_ostream &operator<<(raw_ostream &OS,
+                               const ArrayRef<T> &ByteArray) {
+  const char *Sep = "";
+  for (const auto Byte : ByteArray) {
+    OS << Sep << format("%.2x", Byte);
+    Sep = " ";
+  }
+  return OS;
+}
+
 } // namespace bolt
 } // namespace llvm
 
diff --git a/bolt/src/BinaryFunction.cpp b/bolt/src/BinaryFunction.cpp
index 47d1e4f1759b..fc4a87533d4f 100644
--- a/bolt/src/BinaryFunction.cpp
+++ b/bolt/src/BinaryFunction.cpp
@@ -81,11 +81,15 @@ AlignMacroOpFusion("align-macro-fusion",
   cl::cat(BoltRelocCategory));
 
 cl::opt<bool>
-PreserveBlocksAlignment("preserve-blocks-alignment",
-  cl::desc("try to preserve basic block alignment"),
+CheckEncoding("check-encoding",
+  cl::desc("perform verification of LLVM instruction encoding/decoding. "
+           "Every instruction in the input is decoded and re-encoded. "
+           "If the resulting bytes do not match the input, a warning message "
+           "is printed."),
   cl::init(false),
   cl::ZeroOrMore,
-  cl::cat(BoltOptCategory));
+  cl::Hidden,
+  cl::cat(BoltCategory));
 
 static cl::opt<bool>
 DotToolTipCode("dot-tooltip-code",
@@ -114,6 +118,13 @@ JumpTables("jump-tables",
   cl::ZeroOrMore,
   cl::cat(BoltOptCategory));
 
+cl::opt<bool>
+PreserveBlocksAlignment("preserve-blocks-alignment",
+  cl::desc("try to preserve basic block alignment"),
+  cl::init(false),
+  cl::ZeroOrMore,
+  cl::cat(BoltOptCategory));
+
 cl::opt<bool>
 PrintDynoStats("dyno-stats",
   cl::desc("print execution info based on profile"),
@@ -1016,6 +1027,23 @@ void BinaryFunction::disassemble(ArrayRef<uint8_t> FunctionData) {
       break;
     }
 
+    // Check integrity of LLVM assembler/disassembler.
+    if (opts::CheckEncoding && !BC.MIB->isBranch(Instruction) &&
+        !BC.MIB->isCall(Instruction) && !BC.MIB->isNoop(Instruction)) {
+      SmallString<256> Code;
+      SmallVector<MCFixup, 4> Fixups;
+      raw_svector_ostream VecOS(Code);
+      BC.MCE->encodeInstruction(Instruction, VecOS, Fixups, *BC.STI);
+      auto EncodedData = ArrayRef<uint8_t>((uint8_t *)Code.data(), Code.size());
+      if (FunctionData.slice(Offset, Size) != EncodedData) {
+        errs() << "BOLT-WARNING: mismatching LLVM encoding detected in "
+               << "function " << *this << ":\n";
+        BC.printInstruction(errs(), Instruction, AbsoluteInstrAddr);
+        errs() << "       input: " << FunctionData.slice(Offset, Size)
+               << "\n      output: " << EncodedData << "\n\n";
+      }
+    }
+
     // Cannot process functions with AVX-512 instructions.
     if (MIB->hasEVEXEncoding(Instruction)) {
       if (opts::Verbosity >= 1) {