X87: Add cmpxchg and lock instructions to x64 and ia32 {dis,}assemblers.

test/cctest/test-disasm-x87.cc

Index: test/cctest/test-disasm-x87.cc
diff --git a/test/cctest/test-disasm-x87.cc b/test/cctest/test-disasm-x87.cc
index 9a4c6d4e7fb44dab46d04b4de64c671fbe91fbc3..5a0dcc20d6d005bccde142bd044fb25d05af07d7 100644
--- a/test/cctest/test-disasm-x87.cc
+++ b/test/cctest/test-disasm-x87.cc
@@ -395,12 +395,30 @@ TEST(DisasmIa320) {
 
   // xchg.
   {
+    __ xchg_b(eax, Operand(eax, 8));
+    __ xchg_w(eax, Operand(ebx, 8));
     __ xchg(eax, eax);
     __ xchg(eax, ebx);
     __ xchg(ebx, ebx);
     __ xchg(ebx, Operand(esp, 12));
   }
 
+  // cmpxchg.
+  {
+    __ cmpxchg_b(Operand(esp, 12), eax);
+    __ cmpxchg_w(Operand(ebx, ecx, times_4, 10000), eax);
+    __ cmpxchg(Operand(ebx, ecx, times_4, 10000), eax);
+  }
+
+  // lock prefix.
+  {
+    __ lock();
+    __ cmpxchg(Operand(esp, 12), ebx);
+
+    __ lock();
+    __ xchg_w(eax, Operand(ecx, 8));
+  }
+
   // Nop instructions
   for (int i = 0; i < 16; i++) {
     __ Nop(i);