diff --git a/lib/Target/X86/X86InstrSSE.td b/lib/Target/X86/X86InstrSSE.td
index 7774057d3da..8377c3a0e60 100644
--- a/lib/Target/X86/X86InstrSSE.td
+++ b/lib/Target/X86/X86InstrSSE.td
@@ -2968,6 +2968,22 @@ def : Pat<(v4i32 (X86vzmovl (bc_v4i32 (loadv2i64 addr:$src)))),
             (MOVZDI2PDIrm addr:$src)>;
 }
 
+// These are the correct encodings of the instructions so that we know how to
+// read correct assembly, even though we continue to emit the wrong ones for
+// compatibility with Darwin's buggy assembler.
+def : InstAlias<"movq\t{$src, $dst|$dst, $src}",
+                (MOV64toPQIrr VR128:$dst, GR64:$src), 0>;
+def : InstAlias<"movq\t{$src, $dst|$dst, $src}",
+                (MOV64toSDrr FR64:$dst, GR64:$src), 0>;
+def : InstAlias<"movq\t{$src, $dst|$dst, $src}",
+                (MOVPQIto64rr GR64:$dst, VR128:$src), 0>;
+def : InstAlias<"movq\t{$src, $dst|$dst, $src}",
+                (MOVSDto64rr GR64:$dst, FR64:$src), 0>;
+def : InstAlias<"movq\t{$src, $dst|$dst, $src}",
+                (VMOVZQI2PQIrr VR128:$dst, GR64:$src), 0>;
+def : InstAlias<"movq\t{$src, $dst|$dst, $src}",
+                (MOVZQI2PQIrr VR128:$dst, GR64:$src), 0>;
+
 //===---------------------------------------------------------------------===//
 // SSE2 - Move Quadword
 //===---------------------------------------------------------------------===//
diff --git a/test/MC/X86/x86-64.s b/test/MC/X86/x86-64.s
index a36ba25a6e7..472748f3b82 100644
--- a/test/MC/X86/x86-64.s
+++ b/test/MC/X86/x86-64.s
@@ -1128,3 +1128,11 @@ xsetbv // CHECK: xsetbv # encoding: [0x0f,0x01,0xd1]
 // CHECK: strq
 // CHECK: encoding: [0x48,0x0f,0x00,0xc8]
 	str %rax
+
+// CHECK: movd %rdi, %xmm0
+// CHECK: encoding: [0x66,0x48,0x0f,0x6e,0xc7]
+	movq %rdi,%xmm0
+
+// CHECK: movd %rdi, %xmm0
+// CHECK: encoding: [0x66,0x48,0x0f,0x6e,0xc7]
+	movd %rdi,%xmm0