diff --git a/lib/Target/X86/AsmParser/X86AsmParser.cpp b/lib/Target/X86/AsmParser/X86AsmParser.cpp
index 525d4cb331c..371662bbfdc 100644
--- a/lib/Target/X86/AsmParser/X86AsmParser.cpp
+++ b/lib/Target/X86/AsmParser/X86AsmParser.cpp
@@ -1152,6 +1152,44 @@ struct X86Operand : public MCParsedAsmOperand {
 
 } // end anonymous namespace.
 
+static bool CheckBaseRegAndIndexReg(unsigned BaseReg, unsigned IndexReg,
+                                    StringRef &ErrMsg) {
+  // If we have both a base register and an index register make sure they are
+  // both 64-bit or 32-bit registers.
+  // To support VSIB, IndexReg can be 128-bit or 256-bit registers.
+  if (BaseReg != 0 && IndexReg != 0) {
+    if (X86MCRegisterClasses[X86::GR64RegClassID].contains(BaseReg) &&
+        (X86MCRegisterClasses[X86::GR16RegClassID].contains(IndexReg) ||
+         X86MCRegisterClasses[X86::GR32RegClassID].contains(IndexReg)) &&
+        IndexReg != X86::RIZ) {
+      ErrMsg = "base register is 64-bit, but index register is not";
+      return true;
+    }
+    if (X86MCRegisterClasses[X86::GR32RegClassID].contains(BaseReg) &&
+        (X86MCRegisterClasses[X86::GR16RegClassID].contains(IndexReg) ||
+         X86MCRegisterClasses[X86::GR64RegClassID].contains(IndexReg)) &&
+        IndexReg != X86::EIZ){
+      ErrMsg = "base register is 32-bit, but index register is not";
+      return true;
+    }
+    if (X86MCRegisterClasses[X86::GR16RegClassID].contains(BaseReg)) {
+      if (X86MCRegisterClasses[X86::GR32RegClassID].contains(IndexReg) ||
+          X86MCRegisterClasses[X86::GR64RegClassID].contains(IndexReg)) {
+        ErrMsg = "base register is 16-bit, but index register is not";
+        return true;
+      }
+      if (((BaseReg == X86::BX || BaseReg == X86::BP) &&
+           IndexReg != X86::SI && IndexReg != X86::DI) ||
+          ((BaseReg == X86::SI || BaseReg == X86::DI) &&
+           IndexReg != X86::BX && IndexReg != X86::BP)) {
+        ErrMsg = "invalid 16-bit base/index register combination";
+        return true;
+      }
+    }
+  }
+  return false;
+}
+
 bool X86AsmParser::doSrcDstMatch(X86Operand &Op1, X86Operand &Op2)
 {
   // Return true and let a normal complaint about bogus operands happen.
@@ -1575,6 +1613,11 @@ X86Operand *X86AsmParser::ParseIntelBracExpression(unsigned SegReg, SMLoc Start,
       else
         return X86Operand::CreateMem(SegReg, Disp, 0, 0, 1, Start, End, Size);
     }
+    StringRef ErrMsg;
+    if (CheckBaseRegAndIndexReg(BaseReg, IndexReg, ErrMsg)) {
+      Error(StartInBrac, ErrMsg);
+      return 0;
+    }
     return X86Operand::CreateMem(SegReg, Disp, BaseReg, IndexReg, Scale, Start,
                                  End, Size);
   }
@@ -2080,38 +2123,11 @@ X86Operand *X86AsmParser::ParseMemOperand(unsigned SegReg, SMLoc MemStart) {
     Error(IndexLoc, "16-bit memory operand may not include only index register");
     return 0;
   }
-  // If we have both a base register and an index register make sure they are
-  // both 64-bit or 32-bit registers.
-  // To support VSIB, IndexReg can be 128-bit or 256-bit registers.
-  if (BaseReg != 0 && IndexReg != 0) {
-    if (X86MCRegisterClasses[X86::GR64RegClassID].contains(BaseReg) &&
-        (X86MCRegisterClasses[X86::GR16RegClassID].contains(IndexReg) ||
-         X86MCRegisterClasses[X86::GR32RegClassID].contains(IndexReg)) &&
-        IndexReg != X86::RIZ) {
-      Error(BaseLoc, "base register is 64-bit, but index register is not");
-      return 0;
-    }
-    if (X86MCRegisterClasses[X86::GR32RegClassID].contains(BaseReg) &&
-        (X86MCRegisterClasses[X86::GR16RegClassID].contains(IndexReg) ||
-         X86MCRegisterClasses[X86::GR64RegClassID].contains(IndexReg)) &&
-        IndexReg != X86::EIZ){
-      Error(BaseLoc, "base register is 32-bit, but index register is not");
-      return 0;
-    }
-    if (X86MCRegisterClasses[X86::GR16RegClassID].contains(BaseReg)) {
-      if (X86MCRegisterClasses[X86::GR32RegClassID].contains(IndexReg) ||
-          X86MCRegisterClasses[X86::GR64RegClassID].contains(IndexReg)) {
-        Error(BaseLoc, "base register is 16-bit, but index register is not");
-        return 0;
-      }
-      if (((BaseReg == X86::BX || BaseReg == X86::BP) &&
-           IndexReg != X86::SI && IndexReg != X86::DI) ||
-          ((BaseReg == X86::SI || BaseReg == X86::DI) &&
-           IndexReg != X86::BX && IndexReg != X86::BP)) {
-        Error(BaseLoc, "invalid 16-bit base/index register combination");
-        return 0;
-      }
-    }
+
+  StringRef ErrMsg;
+  if (CheckBaseRegAndIndexReg(BaseReg, IndexReg, ErrMsg)) {
+    Error(BaseLoc, ErrMsg);
+    return 0;
   }
 
   return X86Operand::CreateMem(SegReg, Disp, BaseReg, IndexReg, Scale,
diff --git a/test/MC/X86/intel-syntax-invalid-basereg.s b/test/MC/X86/intel-syntax-invalid-basereg.s
new file mode 100644
index 00000000000..fe026e18408
--- /dev/null
+++ b/test/MC/X86/intel-syntax-invalid-basereg.s
@@ -0,0 +1,7 @@
+// RUN: not llvm-mc -triple x86_64-unknown-unknown %s 2> %t.err
+// RUN: FileCheck < %t.err %s
+
+.intel_syntax
+
+// CHECK: error: base register is 64-bit, but index register is not
+    lea rax, [rdi + edx]