What is the ARMCC compiler option for automatic insertion of prefetching instructions during compilation process?

Question

I'm trying to evaluate the gain if I insert prefetching instructions manually into a source code and when I order the compiler ARMCC to insert that prefetching instructions automatically. But I don't know the compilation option (command-line) that orders ARMCC compiler to insert prefetching instructions automatically during the compilation process. Thanks !

Answer 1

They are under documentation topic Chapter 10 Compiler-specific Features

__pld: This intrinsic inserts a data prefetch, for example PLD, into the instruction stream generated by the compiler. It enables you to signal to the memory system from your C or C++ program that a data load from an address is likely in the near future.

__pldw: This intrinsic inserts a PLDW instruction into the instruction stream generated by the compiler. It enables you to signal to the memory system from your C or C++ program that a data load from an address with an intention to write is likely in the near future. This intrinsic inserts a PLDW instruction into the instruction stream generated by the compiler. It enables you to signal to the memory system from your C or C++ program that a data load from an address with an intention to write is likely in the near future.

__pli: This intrinsic inserts an instruction prefetch, for example PLI, into the instruction stream generated by the compiler. It enables you to signal to the memory system from your C or C++ program that an instruction load from an address is likely in the near future.