pub unsafe fn value(&mut self, builder: LLVMBuilderRef, value: LLVMValueRef) -> LLVMValueRef {
        LLVMBuildStructGEP(builder, value, VALUE_INDEX, c_str!("slot.value"))
    }
Return the value pointer for the provide slot.

The slot should be a pointer.
weld/src/codegen/llvm2/dict.rs