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ecc8479a01
This is sort of a followup to D37310; that basically fixed the same issue, but then the libstdc++ implementation of <atomic> changed. Re-fix the the issue in essentially the same way: look through the addressof operation to find the alignment of the underlying object. Differential Revision: https://reviews.llvm.org/D123950
51 lines
1.1 KiB
C++
51 lines
1.1 KiB
C++
// RUN: %clang_cc1 %s -std=c++14 -emit-llvm -o - -triple=x86_64-linux-gnu | FileCheck %s
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struct AM {
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int f1, f2;
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};
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alignas(8) AM m;
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AM load1() {
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AM am;
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// m is declared to align to 8bytes, so generate load atomic instead
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// of libcall.
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// CHECK-LABEL: @_Z5load1v
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// CHECK: load atomic {{.*}} monotonic, align 8
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__atomic_load(&m, &am, 0);
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return am;
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}
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struct BM {
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int f1;
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alignas(8) AM f2;
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};
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BM bm;
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AM load2() {
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AM am;
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// BM::f2 is declared to align to 8bytes, so generate load atomic instead
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// of libcall.
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// CHECK-LABEL: @_Z5load2v
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// CHECK: load atomic {{.*}} monotonic, align 8
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__atomic_load(&bm.f2, &am, 0);
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return am;
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}
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namespace std {
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template <class _Tp>
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inline constexpr
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__attribute__ ((__visibility__("hidden"), __internal_linkage__))
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_Tp* __addressof(_Tp& __x) noexcept
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{
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return __builtin_addressof(__x);
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}
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}
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AM load3() {
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AM am;
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// m is declared to align to 8bytes, so generate load atomic instead
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// of libcall.
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// CHECK-LABEL: @_Z5load3v
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// CHECK: load atomic {{.*}} monotonic, align 8
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__atomic_load(std::__addressof(m), &am, 0);
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return am;
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}
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