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[Transforms] Introduce BuildBuiltins.h atomic helpers #134455

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[Transforms] Introduce BuildBuiltins.h atomic helpers #134455

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70c65b3
Add BuildBuiltins utilities for atomic load,store,cmpxchg
Meinersbur Apr 4, 2025
b072cab
Undo moving spltBB
Meinersbur Apr 7, 2025
03f7d72
Address review
Meinersbur Apr 10, 2025
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80 changes: 80 additions & 0 deletions llvm/include/llvm/Analysis/TargetLibraryInfo.def
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Original file line number Diff line number Diff line change
Expand Up @@ -462,11 +462,91 @@ TLI_DEFINE_ENUM_INTERNAL(atomic_load)
TLI_DEFINE_STRING_INTERNAL("__atomic_load")
TLI_DEFINE_SIG_INTERNAL(Void, SizeT, Ptr, Ptr, Int)

/// int8_t __atomic_load_1(void *ptr, int memorder);
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Is the choice to let __atomic_load_N return a sized integer, while __atomic_load return void based on maintaining proximity with GCC's definitions of these builtins? Or is there any other reason which I am missing?

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This is the GCC-defined ABI, see https://gcc.gnu.org/wiki/Atomic/GCCMM/LIbrary#GCC_intrinsics for reference.

__atomic_load_N returns the load value, possible due to having a known size that fits into a register (or pre-allocated stack slot, depending on calling convention). __atomic_load reads a dynamic number of bytes and hence cannot be pre-allocated/passed by register.

TLI_DEFINE_ENUM_INTERNAL(atomic_load_1)
TLI_DEFINE_STRING_INTERNAL("__atomic_load_1")
TLI_DEFINE_SIG_INTERNAL(Int8, Ptr, Int)

/// int16_t __atomic_load_2(void *ptr, int memorder);
TLI_DEFINE_ENUM_INTERNAL(atomic_load_2)
TLI_DEFINE_STRING_INTERNAL("__atomic_load_2")
TLI_DEFINE_SIG_INTERNAL(Int16, Ptr, Int)

/// int32_t __atomic_load_4(void *ptr, int memorder);
TLI_DEFINE_ENUM_INTERNAL(atomic_load_4)
TLI_DEFINE_STRING_INTERNAL("__atomic_load_4")
TLI_DEFINE_SIG_INTERNAL(Int32, Ptr, Int)

/// int64_t __atomic_load_8(void *ptr int memorder);
TLI_DEFINE_ENUM_INTERNAL(atomic_load_8)
TLI_DEFINE_STRING_INTERNAL("__atomic_load_8")
TLI_DEFINE_SIG_INTERNAL(Int64, Ptr, Int)

/// int128_t __atomic_load_16(void *ptr, int memorder);
TLI_DEFINE_ENUM_INTERNAL(atomic_load_16)
TLI_DEFINE_STRING_INTERNAL("__atomic_load_16")
TLI_DEFINE_SIG_INTERNAL(Int128, Ptr, Int)

/// void __atomic_store(size_t size, void *mptr, void *vptr, int smodel);
TLI_DEFINE_ENUM_INTERNAL(atomic_store)
TLI_DEFINE_STRING_INTERNAL("__atomic_store")
TLI_DEFINE_SIG_INTERNAL(Void, SizeT, Ptr, Ptr, Int)

/// void __atomic_store_1(void *ptr, int8_t val, int smodel);
TLI_DEFINE_ENUM_INTERNAL(atomic_store_1)
TLI_DEFINE_STRING_INTERNAL("__atomic_store_1")
TLI_DEFINE_SIG_INTERNAL(Void, Ptr, Int8, Int)

/// void __atomic_store_2(void *ptr, int16_t val, int smodel);
TLI_DEFINE_ENUM_INTERNAL(atomic_store_2)
TLI_DEFINE_STRING_INTERNAL("__atomic_store_2")
TLI_DEFINE_SIG_INTERNAL(Void, Ptr, Int16, Int)

/// void __atomic_store_4(void *ptr, int32_t val, int smodel);
TLI_DEFINE_ENUM_INTERNAL(atomic_store_4)
TLI_DEFINE_STRING_INTERNAL("__atomic_store_4")
TLI_DEFINE_SIG_INTERNAL(Void, Ptr, Int32, Int)

/// void __atomic_store_8(void *ptr, int64_t val, int smodel);
TLI_DEFINE_ENUM_INTERNAL(atomic_store_8)
TLI_DEFINE_STRING_INTERNAL("__atomic_store_8")
TLI_DEFINE_SIG_INTERNAL(Void, Ptr, Int64, Int)

/// void __atomic_store_16(void *ptr, int128_t val, int smodel);
TLI_DEFINE_ENUM_INTERNAL(atomic_store_16)
TLI_DEFINE_STRING_INTERNAL("__atomic_store_16")
TLI_DEFINE_SIG_INTERNAL(Void, Ptr, Int128, Int)

/// bool __atomic_compare_exchange(size_t size, void *ptr, void *expected, void *desired, int success, int failure);
TLI_DEFINE_ENUM_INTERNAL(atomic_compare_exchange)
TLI_DEFINE_STRING_INTERNAL("__atomic_compare_exchange")
TLI_DEFINE_SIG_INTERNAL(Bool, SizeT, Ptr, Ptr, Ptr, Int, Int)

/// bool __atomic_compare_exchange_1(void *ptr, void *expected, uint8_t desired, int success, int failure);
TLI_DEFINE_ENUM_INTERNAL(atomic_compare_exchange_1)
TLI_DEFINE_STRING_INTERNAL("__atomic_compare_exchange_1")
TLI_DEFINE_SIG_INTERNAL(Bool, Ptr, Ptr, Int8, Int, Int)

/// bool __atomic_compare_exchange_2(void *ptr, void *expected, uint16_t desired, int success, int failure);
TLI_DEFINE_ENUM_INTERNAL(atomic_compare_exchange_2)
TLI_DEFINE_STRING_INTERNAL("__atomic_compare_exchange_2")
TLI_DEFINE_SIG_INTERNAL(Bool, Ptr, Ptr, Int16, Int, Int)

/// bool __atomic_compare_exchange_4(void *ptr, void *expected, uint32_t desired, int success, int failure);
TLI_DEFINE_ENUM_INTERNAL(atomic_compare_exchange_4)
TLI_DEFINE_STRING_INTERNAL("__atomic_compare_exchange_4")
TLI_DEFINE_SIG_INTERNAL(Bool, Ptr, Ptr, Int32, Int, Int)

/// bool __atomic_compare_exchange_8(void *ptr, void *expected, uint64_t desired, int success, int failure);
TLI_DEFINE_ENUM_INTERNAL(atomic_compare_exchange_8)
TLI_DEFINE_STRING_INTERNAL("__atomic_compare_exchange_8")
TLI_DEFINE_SIG_INTERNAL(Bool, Ptr, Ptr, Int64, Int, Int)

/// bool __atomic_compare_exchange_16(void *ptr, void *expected, uint128_t desired, int success, int failure);
TLI_DEFINE_ENUM_INTERNAL(atomic_compare_exchange_16)
TLI_DEFINE_STRING_INTERNAL("__atomic_compare_exchange_16")
TLI_DEFINE_SIG_INTERNAL(Bool, Ptr, Ptr, Int128, Int, Int)

/// double __cosh_finite(double x);
TLI_DEFINE_ENUM_INTERNAL(cosh_finite)
TLI_DEFINE_STRING_INTERNAL("__cosh_finite")
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22 changes: 22 additions & 0 deletions llvm/include/llvm/Support/AtomicOrdering.h
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Expand Up @@ -158,6 +158,28 @@ inline AtomicOrderingCABI toCABI(AtomicOrdering AO) {
return lookup[static_cast<size_t>(AO)];
}

inline AtomicOrdering fromCABI(AtomicOrderingCABI AO) {
// Acquire is the the closest but still stronger ordering of consume.
static const AtomicOrdering lookup[8] = {
/* relaxed */ AtomicOrdering::Monotonic,
/* consume */ AtomicOrdering::Acquire,
/* acquire */ AtomicOrdering::Acquire,
/* release */ AtomicOrdering::Release,
/* acq_rel */ AtomicOrdering::AcquireRelease,
/* acq_seq */ AtomicOrdering::SequentiallyConsistent,
};
return lookup[static_cast<size_t>(AO)];
}

inline AtomicOrdering fromCABI(int64_t AO) {
if (!isValidAtomicOrderingCABI(AO)) {
// This fallback is what CGAtomic does
return AtomicOrdering::Monotonic;
}
assert(isValidAtomicOrderingCABI(AO));
return fromCABI(static_cast<AtomicOrderingCABI>(AO));
}

} // end namespace llvm

#endif // LLVM_SUPPORT_ATOMICORDERING_H
49 changes: 49 additions & 0 deletions llvm/include/llvm/Testing/Support/Error.h
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Expand Up @@ -80,6 +80,48 @@ class ValueMatchesPoly {
M Matcher;
};

template <typename RefT> class StoreResultMatcher {
class Impl : public testing::MatcherInterface<
const llvm::detail::ExpectedHolder<RefT> &> {
public:
explicit Impl(RefT &Ref) : Ref(Ref) {}

bool
MatchAndExplain(const llvm::detail::ExpectedHolder<RefT> &Holder,
testing::MatchResultListener *listener) const override {
// If failed to get a value, fail the ASSERT/EXPECT and do not store any
// value
if (!Holder.Success())
return false;

// Succeeded with a value, remember it
Ref = *Holder.Exp;

return true;
}

void DescribeTo(std::ostream *OS) const override { *OS << "succeeded"; }

void DescribeNegationTo(std::ostream *OS) const override {
*OS << "failed";
}

private:
RefT &Ref;
};

public:
explicit StoreResultMatcher(RefT &Ref) : Ref(Ref) {}

template <typename T>
operator testing::Matcher<const llvm::detail::ExpectedHolder<T> &>() const {
return MakeMatcher(new Impl(Ref));
}

private:
RefT &Ref;
};

template <typename InfoT>
class ErrorMatchesMono : public testing::MatcherInterface<const ErrorHolder &> {
public:
Expand Down Expand Up @@ -222,6 +264,13 @@ detail::ValueMatchesPoly<M> HasValue(M Matcher) {
return detail::ValueMatchesPoly<M>(Matcher);
}

/// Matches on Expected<T> values that succeed, but also stores its value into a
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Maybe this addition to the testing support should go in a different PR?

/// variable.
template <typename RefT>
detail::StoreResultMatcher<RefT> StoreResult(RefT &Ref) {
return detail::StoreResultMatcher<RefT>(Ref);
}

} // namespace llvm

#endif
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