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
}
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;
}