Commit c510d367 authored by Tom Stellard's avatar Tom Stellard
Browse files

Merging r318658: 

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r318658 | achurbanov | 2017-11-20 08:00:42 -0800 (Mon, 20 Nov 2017) | 4 lines

Fixed OMP doacross implementation on 32-bit platforms.

Differential Revision: https://reviews.llvm.org/D40171

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llvm-svn: 319053
parent 786065d5

openmp/runtime/src/kmp_csupport.cpp

+15 −8
Original line number Diff line number Diff line
@@ -3095,23 +3095,30 @@ void __kmpc_doacross_init(ident_t *loc, int gtid, int num_dims, 
    __kmp_wait_yield_4((volatile kmp_uint32 *)&sh_buf->doacross_buf_idx, idx,

                       __kmp_eq_4, NULL);

  }

#if KMP_32_BIT_ARCH

  // Check if we are the first thread. After the CAS the first thread gets 0,

  // others get 1 if initialization is in progress, allocated pointer otherwise.

  // Treat pointer as volatile integer (value 0 or 1) until memory is allocated.

  flags = (kmp_uint32 *)KMP_COMPARE_AND_STORE_RET32(

      (volatile kmp_int32 *)&sh_buf->doacross_flags, NULL, 1);

#else

  flags = (kmp_uint32 *)KMP_COMPARE_AND_STORE_RET64(

      (kmp_int64 *)&sh_buf->doacross_flags, NULL, (kmp_int64)1);

      (volatile kmp_int64 *)&sh_buf->doacross_flags, NULL, 1LL);

#endif

  if (flags == NULL) {

    // we are the first thread, allocate the array of flags

    kmp_int64 size =

        trace_count / 8 + 8; // in bytes, use single bit per iteration

    size_t size = trace_count / 8 + 8; // in bytes, use single bit per iteration

    sh_buf->doacross_flags = (kmp_uint32 *)__kmp_thread_calloc(th, size, 1);

  } else if ((kmp_int64)flags == 1) {

  } else if (flags == (kmp_uint32 *)1) {

#if KMP_32_BIT_ARCH

    // initialization is still in progress, need to wait

    while ((volatile kmp_int64)sh_buf->doacross_flags == 1) {

    while (*(volatile kmp_int32 *)&sh_buf->doacross_flags == 1)

#else

    while (*(volatile kmp_int64 *)&sh_buf->doacross_flags == 1LL)

#endif

      KMP_YIELD(TRUE);

  }

  }

  KMP_DEBUG_ASSERT((kmp_int64)sh_buf->doacross_flags >

                   1); // check value of pointer

  KMP_DEBUG_ASSERT(sh_buf->doacross_flags > (kmp_uint32 *)1); // check ptr value

  pr_buf->th_doacross_flags =

      sh_buf->doacross_flags; // save private copy in order to not

  // touch shared buffer on each iteration