[Bug target/65697] __atomic memory barriers not strong enough for __sync builtins

[mwahab at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65697

--- Comment #66 from mwahab at gcc dot gnu.org ---
Author: mwahab
Date: Wed Aug  5 11:20:59 2015
New Revision: 226618

URL: https://gcc.gnu.org/viewcvs?rev=226618&root=gcc&view=rev
Log:
        Backport from trunk
        2015-05-12  Andrew MacLeod  <amacleod@redhat.com>

        PR target/65697
        * coretypes.h (MEMMODEL_SYNC, MEMMODEL_BASE_MASK): New macros.
        (enum memmodel): Add SYNC_{ACQUIRE,RELEASE,SEQ_CST}.
        * tree.h (memmodel_from_int, memmodel_base, is_mm_relaxed)
        (is_mm_consume,is_mm_acquire, is_mm_release, is_mm_acq_rel)
        (is_mm_seq_cst, is_mm_sync): New accessor functions.
        * builtins.c (expand_builtin_sync_operation)
        (expand_builtin_compare_and_swap): Use MEMMODEL_SYNC_SEQ_CST.
        (expand_builtin_sync_lock_release): Use MEMMODEL_SYNC_RELEASE.
        (get_memmodel,  expand_builtin_atomic_compare_exchange)
        (expand_builtin_atomic_load, expand_builtin_atomic_store)
        (expand_builtin_atomic_clear): Use new accessor routines.
        (expand_builtin_sync_synchronize): Use MEMMODEL_SYNC_SEQ_CST.
        * optabs.c (expand_compare_and_swap_loop): Use MEMMODEL_SYNC_SEQ_CST.
        (maybe_emit_sync_lock_test_and_set): Use new accessors and
        MEMMODEL_SYNC_ACQUIRE.
        (expand_sync_lock_test_and_set): Use MEMMODEL_SYNC_ACQUIRE.
        (expand_mem_thread_fence, expand_mem_signal_fence, expand_atomic_load)
        (expand_atomic_store): Use new accessors.
        * emit-rtl.c (need_atomic_barrier_p): Add additional enum cases.
        * tsan.c (instrument_builtin_call): Update check for memory model
beyond
        final enum to use MEMMODEL_LAST.
        * c-family/c-common.c: Use new accessor for memmodel_base.
        * config/aarch64/aarch64.c (aarch64_expand_compare_and_swap): Use new
        accessors.
        * config/aarch64/atomics.md (atomic_load<mode>,atomic_store<mode>)
        (arch64_load_exclusive<mode>, aarch64_store_exclusive<mode>)
        (mem_thread_fence, *dmb): Likewise.
        * config/alpha/alpha.c (alpha_split_compare_and_swap)
        (alpha_split_compare_and_swap_12): Likewise.
        * config/arm/arm.c (arm_expand_compare_and_swap)
        (arm_split_compare_and_swap, arm_split_atomic_op): Likewise.
        * config/arm/sync.md (atomic_load<mode>, atomic_store<mode>)
        (atomic_loaddi): Likewise.
        * config/i386/i386.c (ix86_destroy_cost_data, ix86_memmodel_check):
        Likewise.
        * config/i386/sync.md (mem_thread_fence, atomic_store<mode>): Likewise.
        * config/ia64/ia64.c (ia64_expand_atomic_op): Add new memmodel cases
and
        use new accessors.
        * config/ia64/sync.md (mem_thread_fence, atomic_load<mode>)
        (atomic_store<mode>, atomic_compare_and_swap<mode>)
        (atomic_exchange<mode>): Use new accessors.
        * config/mips/mips.c (mips_process_sync_loop): Likewise.
        * config/pa/pa.md (atomic_loaddi, atomic_storedi): Likewise.
        * config/rs6000/rs6000.c (rs6000_pre_atomic_barrier)
        (rs6000_post_atomic_barrier): Add new cases.
        (rs6000_expand_atomic_compare_and_swap): Use new accessors.
        * config/rs6000/sync.md (mem_thread_fence): Add new cases.
        (atomic_load<mode>): Add new cases and use new accessors.
        (store_quadpti): Add new cases.
        * config/s390/s390.md (mem_thread_fence, atomic_store<mode>): Use new
        accessors.
        * config/sparc/sparc.c (sparc_emit_membar_for_model): Use new
accessors.
        * doc/extend.texi: Update docs to indicate 16 bits are used for memory
        model, not 8.


Modified:
    branches/gcc-5-branch/gcc/ChangeLog
    branches/gcc-5-branch/gcc/builtins.c
    branches/gcc-5-branch/gcc/c-family/c-common.c
    branches/gcc-5-branch/gcc/config/aarch64/aarch64.c
    branches/gcc-5-branch/gcc/config/aarch64/atomics.md
    branches/gcc-5-branch/gcc/config/alpha/alpha.c
    branches/gcc-5-branch/gcc/config/arm/arm.c
    branches/gcc-5-branch/gcc/config/arm/sync.md
    branches/gcc-5-branch/gcc/config/i386/i386.c
    branches/gcc-5-branch/gcc/config/i386/sync.md
    branches/gcc-5-branch/gcc/config/ia64/ia64.c
    branches/gcc-5-branch/gcc/config/ia64/sync.md
    branches/gcc-5-branch/gcc/config/mips/mips.c
    branches/gcc-5-branch/gcc/config/pa/pa.md
    branches/gcc-5-branch/gcc/config/rs6000/rs6000.c
    branches/gcc-5-branch/gcc/config/rs6000/sync.md
    branches/gcc-5-branch/gcc/config/s390/s390.md
    branches/gcc-5-branch/gcc/config/sparc/sparc.c
    branches/gcc-5-branch/gcc/coretypes.h
    branches/gcc-5-branch/gcc/doc/extend.texi
    branches/gcc-5-branch/gcc/emit-rtl.c
    branches/gcc-5-branch/gcc/optabs.c
    branches/gcc-5-branch/gcc/tree.h
    branches/gcc-5-branch/gcc/tsan.c