Handle "inplace" ops and unary ops w/ assembler

crosstest/test_bitmanip.cpp

 //===- subzero/crosstest/test_bitmanip.cpp - Implementation for tests. ----===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // This aims to test that all the bit manipulation intrinsics work, via
@@ skipping 22 matching lines @@
     return sum;                                                                \
   }                                                                            \
   type test_const_##inst(type ignored) {                                       \
     return my_##inst(static_cast<type>(0x12340));                              \
   }
 
 FOR_ALL_BMI_OP_TYPES(X)
 #undef X
 
 #define X(type, builtin_name)                                                  \
-  type test_bswap(type a) { return builtin_name(a); }
+  type test_bswap(type a) { return builtin_name(a); }                          \
+  type test_bswap_alloca(type a) {                                             \
+    const size_t buf_size = 8;                                                 \
+    type buf[buf_size];                                                        \
+    for (size_t i = 0; i < buf_size; ++i) {                                    \
+      buf[i] = builtin_name(a * i) + builtin_name(a + i);                      \
+    }                                                                          \
+    type sum = 0;                                                              \
+    for (size_t i = 0; i < buf_size; ++i) {                                    \
+      sum += buf[i];                                                           \
+    }                                                                          \
+    return sum;                                                                \
+  }
 BSWAP_TABLE
 #undef X