diff --git a/llvm/include/llvm/IR/DerivedTypes.h b/llvm/include/llvm/IR/DerivedTypes.h
index 18643075430370..306d388cb8a7d8 100644
--- a/llvm/include/llvm/IR/DerivedTypes.h
+++ b/llvm/include/llvm/IR/DerivedTypes.h
@@ -519,12 +519,6 @@ class VectorType : public Type {
     return Scalable;
   }
 
-  /// Return the minimum number of bits in the Vector type.
-  /// Returns zero when the vector is a vector of pointers.
-  unsigned getBitWidth() const {
-    return getNumElements() * getElementType()->getPrimitiveSizeInBits();
-  }
-
   /// Methods for support type inquiry through isa, cast, and dyn_cast.
   static bool classof(const Type *T) {
     return T->getTypeID() == VectorTyID;
diff --git a/llvm/lib/IR/Type.cpp b/llvm/lib/IR/Type.cpp
index 17ca43cbbccb75..e8c693aedf64fb 100644
--- a/llvm/lib/IR/Type.cpp
+++ b/llvm/lib/IR/Type.cpp
@@ -68,20 +68,20 @@ bool Type::canLosslesslyBitCastTo(Type *Ty) const {
     return false;
 
   // Vector -> Vector conversions are always lossless if the two vector types
-  // have the same size, otherwise not.  Also, 64-bit vector types can be
-  // converted to x86mmx.
-  if (auto *thisPTy = dyn_cast<VectorType>(this)) {
-    if (auto *thatPTy = dyn_cast<VectorType>(Ty))
-      return thisPTy->getBitWidth() == thatPTy->getBitWidth();
-    if (Ty->getTypeID() == Type::X86_MMXTyID &&
-        thisPTy->getBitWidth() == 64)
-      return true;
-  }
-
-  if (this->getTypeID() == Type::X86_MMXTyID)
-    if (auto *thatPTy = dyn_cast<VectorType>(Ty))
-      if (thatPTy->getBitWidth() == 64)
-        return true;
+  // have the same size, otherwise not.
+  if (isa<VectorType>(this) && isa<VectorType>(Ty))
+    return getPrimitiveSizeInBits() == Ty->getPrimitiveSizeInBits();
+
+  //  64-bit fixed width vector types can be losslessly converted to x86mmx.
+  if (((isa<VectorType>(this) &&
+        !cast<VectorType>(this)->getElementCount().Scalable) &&
+       Ty->isX86_MMXTy()) &&
+      getPrimitiveSizeInBits().getFixedSize() == 64)
+    return true;
+  if ((isX86_MMXTy() && (isa<VectorType>(Ty) &&
+                         !cast<VectorType>(Ty)->getElementCount().Scalable)) &&
+      Ty->getPrimitiveSizeInBits().getFixedSize() == 64)
+    return true;
 
   // At this point we have only various mismatches of the first class types
   // remaining and ptr->ptr. Just select the lossless conversions. Everything
@@ -125,7 +125,10 @@ TypeSize Type::getPrimitiveSizeInBits() const {
     return TypeSize::Fixed(cast<IntegerType>(this)->getBitWidth());
   case Type::VectorTyID: {
     const VectorType *VTy = cast<VectorType>(this);
-    return TypeSize(VTy->getBitWidth(), VTy->isScalable());
+    ElementCount EC = VTy->getElementCount();
+    TypeSize ETS = VTy->getElementType()->getPrimitiveSizeInBits();
+    assert(!ETS.isScalable() && "Vector type should have fixed-width elements");
+    return {ETS.getFixedSize() * EC.Min, EC.Scalable};
   }
   default: return TypeSize::Fixed(0);
   }
diff --git a/llvm/unittests/AsmParser/AsmParserTest.cpp b/llvm/unittests/AsmParser/AsmParserTest.cpp
index d5f734d390af93..198191bf435fd9 100644
--- a/llvm/unittests/AsmParser/AsmParserTest.cpp
+++ b/llvm/unittests/AsmParser/AsmParserTest.cpp
@@ -232,7 +232,7 @@ TEST(AsmParserTest, TypeWithSlotMappingParsing) {
   // Check the details of the vector.
   VectorType *VT = cast<VectorType>(Ty);
   ASSERT_TRUE(VT->getNumElements() == 5);
-  ASSERT_TRUE(VT->getBitWidth() == 160);
+  ASSERT_TRUE(VT->getPrimitiveSizeInBits().getFixedSize() == 160);
   Ty = VT->getElementType();
   ASSERT_TRUE(Ty->isIntegerTy());
   ASSERT_TRUE(Ty->getPrimitiveSizeInBits() == 32);
@@ -364,7 +364,7 @@ TEST(AsmParserTest, TypeAtBeginningWithSlotMappingParsing) {
   // Check the details of the vector.
   VectorType *VT = cast<VectorType>(Ty);
   ASSERT_TRUE(VT->getNumElements() == 5);
-  ASSERT_TRUE(VT->getBitWidth() == 160);
+  ASSERT_TRUE(VT->getPrimitiveSizeInBits().getFixedSize() == 160);
   Ty = VT->getElementType();
   ASSERT_TRUE(Ty->isIntegerTy());
   ASSERT_TRUE(Ty->getPrimitiveSizeInBits() == 32);