[ia32] Better code generation for materialization of float/double constants.

src/ia32/disasm-ia32.cc

Index: src/ia32/disasm-ia32.cc
diff --git a/src/ia32/disasm-ia32.cc b/src/ia32/disasm-ia32.cc
index 22c2a55c17b9413c413fd064bbbf2bbf68c3d1ea..04279d08bfb751afffe8d5025b9d1300ae392ce1 100644
--- a/src/ia32/disasm-ia32.cc
+++ b/src/ia32/disasm-ia32.cc
@@ -1386,6 +1386,15 @@ int DisassemblerIA32::InstructionDecode(v8::internal::Vector<char> out_buffer,
                            NameOfXMMRegister(regop),
                            NameOfXMMRegister(rm));
             data++;
+          } else if (*data == 0x72) {
+            data++;
+            int mod, regop, rm;
+            get_modrm(*data, &mod, &regop, &rm);
+            int8_t imm8 = static_cast<int8_t>(data[1]);
+            DCHECK(regop == esi || regop == edx);
+            AppendToBuffer("%s %s,%d", (regop == esi) ? "pslld" : "psrld",
+                           NameOfXMMRegister(rm), static_cast<int>(imm8));
+            data += 2;
           } else if (*data == 0x73) {
             data++;
             int mod, regop, rm;