Re: [omr-dev] Is this correct IL codegen?

[Dibyendu Majumdar <mobile@xxxxxxxxxxxxxxx>]

I guess part of the question is whether indirect load/store IL
supports array offsets of the form base[index] or do I need to compute
the address?

Thanks and Regards
Dibyendu

On 10 June 2018 at 23:21, Dibyendu Majumdar <mobile@xxxxxxxxxxxxxxx> wrote:
> Hi,
>
> I am trying to create an api that lets me:
>
> a) Allocate local stack space (alloca)
> b) Load/store values from the allocated space
>
> There is some C scaffolding here but the operation should be obvious -
> I would like to know if this is correct?
>
> Many thanks
> Regards
> Dibyendu
>
> // Create local array (alloca equivalent)
> JIT_SymbolRef JIT_CreateLocalByteArray(JIT_ILInjectorRef ilinjector,
>                                        uint32_t size) {
>   auto injector = unwrap_ilinjector(ilinjector);
>   return wrap_symbolref(injector->symRefTab()->createLocalPrimArray(
>       size, injector->methodSymbol(),
>       8 /*apparently 8 means Java bytearray! */));
> }
>
> // Convert symbol ref to address
> JIT_NodeRef JIT_LoadAddress(JIT_ILInjectorRef ilinjector,
> JIT_SymbolRef symbol) {
>     auto symref = unwrap_symbolref(symbol);
>     return wrap_node(TR::Node::createWithSymRef(TR::loadaddr, 0, symref));
> }
>
> // Load value from base[index]
> JIT_NodeRef JIT_ArrayLoad(JIT_ILInjectorRef ilinjector, JIT_NodeRef basenode,
>                           JIT_NodeRef indexnode, JIT_Type dt) {
>   auto injector = unwrap_ilinjector(ilinjector);
>   auto base = unwrap_node(basenode);
>   auto index = unwrap_node(indexnode);
>   auto type = TR::DataType((TR::DataTypes)dt);
>   TR::SymbolReference *symRef =
>       injector->symRefTab()->findOrCreateArrayShadowSymbolRef(type, base);
>   TR::Node *load = TR::Node::createWithSymRef(
>       TR::ILOpCode::indirectLoadOpCode(type), 1, index, 0, symRef);
>   return wrap_node(load);
> }
>
> //  Store base[index] = value
> void JIT_ArrayStore(JIT_ILInjectorRef ilinjector, JIT_NodeRef basenode,
>     JIT_NodeRef indexnode, JIT_NodeRef valuenode) {
>     auto injector = unwrap_ilinjector(ilinjector);
>     auto base = unwrap_node(basenode);
>     auto index = unwrap_node(indexnode);
>     auto value = unwrap_node(valuenode);
>     auto type = value->getDataType();
>     TR::SymbolReference *symRef =
>         injector->symRefTab()->findOrCreateArrayShadowSymbolRef(type, base);
>     TR::ILOpCodes storeOp = injector->comp()->il.opCodeForIndirectStore(type);
>     TR::Node *store = TR::Node::createWithSymRef(
>         storeOp, 2, index, value, 0, symRef);
>     injector->genTreeTop(store);
> }