diff --git a/clang/include/clang/Basic/CodeGenOptions.def b/clang/include/clang/Basic/CodeGenOptions.def
index b600198998d85b..b78ae61e6509ea 100644
--- a/clang/include/clang/Basic/CodeGenOptions.def
+++ b/clang/include/clang/Basic/CodeGenOptions.def
@@ -375,8 +375,18 @@ ENUM_CODEGENOPT(Inlining, InliningMethod, 2, NormalInlining)
 /// The maximum stack size a function can have to be considered for inlining.
 VALUE_CODEGENOPT(InlineMaxStackSize, 32, UINT_MAX)
 
-// Vector functions library to use.
-ENUM_CODEGENOPT(VecLib, llvm::driver::VectorLibrary, 3, llvm::driver::VectorLibrary::NoLibrary)
+// Define the number of bits required for the VecLib enum
+#define VECLIB_BIT_COUNT (llvm::countPopulation(llvm::driver::VectorLibrary::MaxLibrary))
+
+// Ensure the VecLib bitfield has enough space for future vector libraries.
+// The number of bits is determined automatically based on the number of enum values.
+static_assert(static_cast<size_t>(llvm::driver::VectorLibrary::MaxLibrary) <= (1 << VECLIB_BIT_COUNT),
+              "VecLib bitfield size is too small to accommodate all vector libraries.");
+              
+// VecLib definition in CodeGenOptions.def
+ENUM_CODEGENOPT(VecLib, llvm::driver::VectorLibrary, VECLIB_BIT_COUNT, llvm::driver::VectorLibrary::NoLibrary)
+
+#undef VECLIB_BIT_COUNT
 
 /// The default TLS model to use.
 ENUM_CODEGENOPT(DefaultTLSModel, TLSModel, 2, GeneralDynamicTLSModel)
diff --git a/clang/unittests/CodeGen/AllLibrariesFit.cpp b/clang/unittests/CodeGen/AllLibrariesFit.cpp
new file mode 100644
index 00000000000000..dfe63b557729ee
--- /dev/null
+++ b/clang/unittests/CodeGen/AllLibrariesFit.cpp
@@ -0,0 +1,10 @@
+#include "clang/Basic/CodeGenOptions.h"
+#include "llvm/Driver/Options.h"
+#include "gtest/gtest.h"
+
+TEST(VecLibBitfieldTest, AllLibrariesFit) {
+  // We expect that all vector libraries fit in the bitfield size
+  EXPECT_LE(static_cast<size_t>(llvm::driver::VectorLibrary::MaxLibrary),
+            (1 << VECLIB_BIT_COUNT))
+      << "VecLib bitfield size is too small!";
+ }
diff --git a/clang/unittests/CodeGen/EncodingDecodingTest.cpp b/clang/unittests/CodeGen/EncodingDecodingTest.cpp
new file mode 100644
index 00000000000000..67c89ef07c428b
--- /dev/null
+++ b/clang/unittests/CodeGen/EncodingDecodingTest.cpp
@@ -0,0 +1,17 @@
+TEST(VecLibBitfieldTest, EncodingDecodingTest) {
+  clang::CodeGenOptions Opts;
+
+  // Test encoding and decoding for each vector library
+  for (int i = static_cast<int>(llvm::driver::VectorLibrary::Accelerate);
+       i <= static_cast<int>(llvm::driver::VectorLibrary::MaxLibrary); ++i) {
+
+    Opts.VecLib = static_cast<llvm::driver::VectorLibrary>(i);
+
+    // Encode and then decode
+    llvm::driver::VectorLibrary decodedValue =
+        static_cast<llvm::driver::VectorLibrary>(Opts.VecLib);
+
+    EXPECT_EQ(decodedValue, Opts.VecLib)
+        << "Encoding/Decoding failed for vector library " << i;
+  }
+}
diff --git a/clang/unittests/CodeGen/SimulatedOverflowTest.cpp b/clang/unittests/CodeGen/SimulatedOverflowTest.cpp
new file mode 100644
index 00000000000000..acfeaf7498b6d0
--- /dev/null
+++ b/clang/unittests/CodeGen/SimulatedOverflowTest.cpp
@@ -0,0 +1,26 @@
+// Simulate the addition of a new library without increasing the bitfield size
+enum class SimulatedVectorLibrary {
+  Accelerate = 0,
+  LIBMVEC,
+  MASSV,
+  SVML,
+  SLEEF,
+  Darwin_libsystem_m,
+  ArmPL,
+  AMDLIBM,
+  NoLibrary,
+  // Simulate new addition
+  NewLibrary,
+  MaxLibrary
+};
+
+#define SIMULATED_VECLIB_BIT_COUNT                                             \
+  4 // The current bitfield size (should be 4 for 9 options)
+
+TEST(VecLibBitfieldTest, SimulatedOverflowTest) {
+  // Simulate the addition of a new library and check if the bitfield size is
+  // sufficient
+  EXPECT_LE(static_cast<size_t>(SimulatedVectorLibrary::MaxLibrary),
+            (1 << SIMULATED_VECLIB_BIT_COUNT))
+      << "Simulated VecLib bitfield size overflow!";
+}