abi_win32.cpp

//===-- abi_win32.cpp - x86 ABI description ---------------------*- C++ -*-===//
//
//                         LDC – the LLVM D compiler
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//===----------------------------------------------------------------------===//
//
// The ABI implementation used for 32 bit x86 targets on Windows.
//
//===----------------------------------------------------------------------===//


struct ABI_Win32Layout : AbiLayout {

bool use_sret(jl_datatype_t *dt) override
{
    // Use sret if the size of the argument is not one of 1, 2, 4, 8 bytes
    // This covers the special case of ComplexF32
    size_t size = jl_datatype_size(dt);
    if (size == 1 || size == 2 || size == 4 || size == 8)
        return false;
    return true;
}

bool needPassByRef(jl_datatype_t *dt, AttrBuilder &ab) override
{
    // Use pass by reference for all structs
    if (dt->layout->nfields > 0) {
        ab.addAttribute(Attribute::ByVal);
        return true;
    }
    return false;
}

Type *preferred_llvm_type(jl_datatype_t *dt, bool isret) const override
{
    // Arguments are either scalar or passed by value
    // rewrite integer sized (non-sret) struct to the corresponding integer
    if (!dt->layout->nfields)
        return NULL;
    return Type::getIntNTy(jl_LLVMContext, jl_datatype_nbits(dt));
}

};