SIMD pcmpgtb,w,d,q for x86/x86_64

Rationale:
Enables fast compare gt.

Test: assembler_x86[_64]_test
Change-Id: I0a069649480529f3fec2c2b100e2aaaa2cd79820
diff --git a/compiler/utils/x86/assembler_x86_test.cc b/compiler/utils/x86/assembler_x86_test.cc
index a01eb6d..f75f972 100644
--- a/compiler/utils/x86/assembler_x86_test.cc
+++ b/compiler/utils/x86/assembler_x86_test.cc
@@ -629,6 +629,22 @@
   DriverStr(RepeatFF(&x86::X86Assembler::pcmpeqq, "pcmpeqq %{reg2}, %{reg1}"), "cmpeqq");
 }
 
+TEST_F(AssemblerX86Test, PCmpgtB) {
+  DriverStr(RepeatFF(&x86::X86Assembler::pcmpgtb, "pcmpgtb %{reg2}, %{reg1}"), "cmpgtb");
+}
+
+TEST_F(AssemblerX86Test, PCmpgtW) {
+  DriverStr(RepeatFF(&x86::X86Assembler::pcmpgtw, "pcmpgtw %{reg2}, %{reg1}"), "cmpgtw");
+}
+
+TEST_F(AssemblerX86Test, PCmpgtD) {
+  DriverStr(RepeatFF(&x86::X86Assembler::pcmpgtd, "pcmpgtd %{reg2}, %{reg1}"), "cmpgtd");
+}
+
+TEST_F(AssemblerX86Test, PCmpgtQ) {
+  DriverStr(RepeatFF(&x86::X86Assembler::pcmpgtq, "pcmpgtq %{reg2}, %{reg1}"), "cmpgtq");
+}
+
 TEST_F(AssemblerX86Test, ShufPS) {
   DriverStr(RepeatFFI(&x86::X86Assembler::shufps, 1, "shufps ${imm}, %{reg2}, %{reg1}"), "shufps");
 }