Exemplo n.º 1
0
int
GlobOpt::GetBoundCheckOffsetForSimd(ValueType arrValueType, const IR::Instr *instr, const int oldOffset /* = -1 */)
{
#ifdef ENABLE_SIMDJS
    if (!(Js::IsSimd128LoadStore(instr->m_opcode)))
    {
        return oldOffset;
    }

    if (!arrValueType.IsTypedArray())
    {
        // no need to adjust for other array types, we will not type-spec (see Simd128DoTypeSpecLoadStore)
        return oldOffset;
    }

    Assert(instr->dataWidth == 4 || instr->dataWidth == 8 || instr->dataWidth == 12 || instr->dataWidth == 16);

    int numOfElems = Lowerer::SimdGetElementCountFromBytes(arrValueType, instr->dataWidth);

    // we want to make bound checks more conservative. We compute how many extra elements we need to add to the bound check
    // e.g. if original bound check is value <= Length + offset, and dataWidth is 16 bytes on Float32 array, then we need room for 4 elements. The bound check guarantees room for 1 element.
    // Hence, we need to ensure 3 more: value <= Length + offset - 3
    // We round up since dataWidth may span a partial lane (e.g. dataWidth = 12, bpe = 8 bytes)

    int offsetBias = -(numOfElems - 1);
    // we should always make an existing bound-check more conservative.
    Assert(offsetBias <= 0);
    return oldOffset + offsetBias;
#else
    return oldOffset;
#endif
}
Exemplo n.º 2
0
bool
GlobOpt::Simd128DoTypeSpecLoadStore(IR::Instr *instr, const Value *src1Val, const Value *src2Val, const Value *dstVal, const ThreadContext::SimdFuncSignature *simdFuncSignature)
{
    IR::Opnd *baseOpnd = nullptr, *indexOpnd = nullptr, *valueOpnd = nullptr;
    IR::Opnd *src, *dst;

    bool doTypeSpec = true;

    // value = Ld [arr + index]
    // [arr + index] = St value
    src = instr->GetSrc1();
    dst = instr->GetDst();
    Assert(dst && src && !instr->GetSrc2());

    if (Js::IsSimd128Load(instr->m_opcode))
    {
        Assert(src->IsIndirOpnd());
        baseOpnd = instr->GetSrc1()->AsIndirOpnd()->GetBaseOpnd();
        indexOpnd = instr->GetSrc1()->AsIndirOpnd()->GetIndexOpnd();
        valueOpnd = instr->GetDst();
    }
    else if (Js::IsSimd128Store(instr->m_opcode))
    {
        Assert(dst->IsIndirOpnd());
        baseOpnd = instr->GetDst()->AsIndirOpnd()->GetBaseOpnd();
        indexOpnd = instr->GetDst()->AsIndirOpnd()->GetIndexOpnd();
        valueOpnd = instr->GetSrc1();

        // St(arr, index, value). Make sure value can be Simd128 type-spec'd
        doTypeSpec = doTypeSpec && Simd128CanTypeSpecOpnd(FindValue(valueOpnd->AsRegOpnd()->m_sym)->GetValueInfo()->Type(), simdFuncSignature->args[2]);
    }
    else
    {
        Assert(UNREACHED);
    }

    // array and index operands should have been type-specialized in OptArraySrc: ValueTypes should be definite at this point. If not, don't type-spec.
    // We can be in a loop prepass, where opnd ValueInfo is not set yet. Get the ValueInfo from the Value Table instead.
    ValueType baseOpndType = FindValue(baseOpnd->AsRegOpnd()->m_sym)->GetValueInfo()->Type();
    
    if (IsLoopPrePass())
    {
        doTypeSpec = doTypeSpec && (baseOpndType.IsObject() && baseOpndType.IsTypedArray());
        // indexOpnd might be missing if loading from [0]
        if (indexOpnd != nullptr)
        {
            ValueType indexOpndType = FindValue(indexOpnd->AsRegOpnd()->m_sym)->GetValueInfo()->Type();
            doTypeSpec = doTypeSpec && indexOpndType.IsLikelyInt();
        }
    }
    else
    {
        doTypeSpec = doTypeSpec && (baseOpndType.IsObject() && baseOpndType.IsTypedArray());
        if (indexOpnd != nullptr)
        {
            ValueType indexOpndType = FindValue(indexOpnd->AsRegOpnd()->m_sym)->GetValueInfo()->Type();
            doTypeSpec = doTypeSpec && indexOpndType.IsInt();
        }
    }

    return doTypeSpec;
}