[llvm-dev] [cfe-dev] Create a BlockAddress array from LLVM Pass

[Mustakimur Rahman Khandaker (Mustakim) via llvm-dev]

Sorry for emailing both group.

As I will have a constant array of BlockAddress, what type I should use in Constant Array for its ArrayType declaration?
I am creating the list in following way:

unsigned int nBr = fit->second.size();
llvm::Constant *listBA[nBr];
unsigned int Idx = 0;
for (std::set<llvm::BasicBlock *>::iterator it = fit->second.begin();
it != fit->second.end(); ++it) {
BlockAddress *bba = BlockAddress::get(fn, *it);
listBA[Idx] = bba;
Idx++;
}
Constant *blockItems =
ConstantArray::get(ArrayType::get(?, 8), listBA);

Thanks
On Jan 28 2019, at 3:34 pm, Eli Friedman <efriedma at quicinc.com> wrote:
> Please don’t send questions to both cfe-dev and llvm-dev; usually one or the other is more appropriate (in this case, it’s llvm-dev, since there’s no clang code involved).
>
>
> I think you meant to call ConstantArray::get, not ConstantDataArray::get. (We should probably fix ConstantDataArray::get() to use enable_if or something like that, so your example fails to compile instead of generating a weird runtime error.)
>
> -Eli
>
> From: cfe-dev <cfe-dev-bounces at lists.llvm.org> On Behalf Of Mustakimur Rahman Khandaker (Mustakim) via cfe-dev
> Sent: Monday, January 28, 2019 12:12 PM
> To: llvm-dev at lists.llvm.org; cfe-dev at lists.llvm.org
> Subject: [EXT] [cfe-dev] Create a BlockAddress array from LLVM Pass
>
>
>
> Hi
>
>
> Good day. For the following function local static constant array:
> static const __attribute__((used))
>
> __attribute__((section("data"))) void *codetable[] = {
>
> &&RETURN, &&INCREMENT, &&DECREMENT, &&DOUBLE, &&SWAPWORD};
>
> I have the following in the LLVM IR.
>
>
>
> @sampleCode.codetable = internal global [5 x i8*] [i8* blockaddress(@sampleCode, %19), i8* blockaddress(@sampleCode, %22), i8* blockaddress(@sampleCode, %25), i8* blockaddress(@sampleCode, %28), i8* blockaddress(@sampleCode, %31)], section "data", align 16
>
>
> Here the array elements are labels in c code. I have done following to create the same array from LLVM pass.
>
>
>
> std::vector<BlockAddress *> tmp;
>
> Function *fn = ...
>
> BasicBlock *bb = ...
>
>
> BlockAddress *bba = BlockAddress::get(fn, bb);
>
> tmp.push_back(bba);
>
>
> GlobalVariable *gvar_ptr_abc = new GlobalVariable(
>
> /*Module=*/*fn->getParent(),
>
> /*Type=*/PointerTy,
>
> /*isConstant=*/false,
>
> /*Linkage=*/GlobalValue::InternalLinkage,
>
> /*Initializer=*/0, // has initializer, specified below
>
> /*Name=*/"labelTracker");
>
> gvar_ptr_abc->setAlignment(16);
>
> Constant *blockItems = ConstantDataArray::get(fn->getContext(), tmp);
>
> gvar_ptr_abc->setInitializer(blockItems);
>
> I get error with following: Unsupported type in Type::getScalarTy
>
>
>
> Can anyone suggest what I suppose to do? It is definitely related to my type declaration and BlockAddress items, but I don't know what it is exactly.
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