Fix openmp build on arm

[raj.khem]

Summary

include mm_malloc.h for _mm_malloc/_mm_free definitions
define KMP_MFENCE to nothing in else case, since its used
unconditionally in kmp_barrier.cpp

[kkwli0]

Does D104788 take care of it?

[raj.khem]

In D104821#2837568, @kkwli0 wrote:

Does D104788 take care of it?

yes that fix works and is better than this one. So please ignore this one in favor of D104788

[raj.khem]

https://reviews.llvm.org/D104788 fixes it as well.

openmp/runtime/src/kmp_barrier.h

 /*
  * kmp_barrier.h
  */
 
 //===----------------------------------------------------------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef KMP_BARRIER_H
 #define KMP_BARRIER_H
 
 #include "kmp.h"
+#include "mm_malloc.h"
 
 // Use four cache lines: MLC tends to prefetch the next or previous cache line
 // creating a possible fake conflict between cores, so this is the only way to
 // guarantee that no such prefetch can happen.
 #ifndef KMP_FOURLINE_ALIGN_CACHE
 #define KMP_FOURLINE_ALIGN_CACHE KMP_ALIGN(4 * CACHE_LINE)
 #endif
 

openmp/runtime/src/kmp_os.h

 #define KMP_MFENCE()                                                           \
   if (UNLIKELY(!__kmp_cpuinfo.initialized)) {                                  \
     __kmp_query_cpuid(&__kmp_cpuinfo);                                         \
   }                                                                            \
   if (__kmp_cpuinfo.sse2) {                                                    \
     KMP_MFENCE_();                                                             \
   }
 #define KMP_SFENCE() KMP_SFENCE_()
+#else
+#define KMP_MFENCE()
 #endif
 
 #ifndef KMP_IMB
 #define KMP_IMB() /* nothing to do */
 #endif
 
 #ifndef KMP_ST_REL32
 #define KMP_ST_REL32(A, D) (*(A) = (D))