Remove the extraneous '+0' immediate offset part in PTX load/stores, to improve readability of output PTX code.
This patch adds an NVVM intrinsic and NVPTX codegen for the elect.sync PTX instruction. Lit tests are added in elect.ll and verified through ptxas. PTX ISA reference: https://docs.nvidia.com/cuda/parallel-thread-execution/index.html#parallel-synchronization-and-communication-instructions-elect-sync Signed-off-by: Durgadoss R <durgadossr@nvidia.com>