diff --git a/lib/Target/X86/X86InstrInfo.td b/lib/Target/X86/X86InstrInfo.td
index 0a60eb7..10e9e9a 100644
--- a/lib/Target/X86/X86InstrInfo.td
+++ b/lib/Target/X86/X86InstrInfo.td
@@ -1497,6 +1497,10 @@
 // Match 'movq <largeimm>, <reg>' as an alias for movabsq.
 def : InstAlias<"movq $imm, $reg", (MOV64ri GR64:$reg, i64imm:$imm)>;
 
+// Match 'movq GR64, MMX' as an alias for movd.
+def : InstAlias<"movq $src, $dst", (MMX_MOVD64to64rr VR64:$dst, GR64:$src)>;
+def : InstAlias<"movq $src, $dst", (MMX_MOVD64from64rr GR64:$dst, VR64:$src)>;
+
 // movsd with no operands (as opposed to the SSE scalar move of a double) is an
 // alias for movsl. (as in rep; movsd)
 def : InstAlias<"movsd", (MOVSD)>;
diff --git a/test/MC/X86/x86-64.s b/test/MC/X86/x86-64.s
index b8b093c..f1a14e8 100644
--- a/test/MC/X86/x86-64.s
+++ b/test/MC/X86/x86-64.s
@@ -902,3 +902,10 @@
 	idiv	0x7eed,%eax
 	idiv	0xbabecafe,%eax
 	idiv	0x12345678,%eax
+
+// PR8524
+movd	%rax, %mm5 // CHECK: movd %rax, %mm5 # encoding: [0x48,0x0f,0x6e,0xe8]
+movd	%mm5, %rbx // CHECK: movd %mm5, %rbx # encoding: [0x48,0x0f,0x7e,0xeb]
+movq	%rax, %mm5 // CHECK: movd %rax, %mm5 # encoding: [0x48,0x0f,0x6e,0xe8]
+movq	%mm5, %rbx // CHECK: movd %mm5, %rbx # encoding: [0x48,0x0f,0x7e,0xeb]
+