Change ptx version for PTX target

The ptx I generated through LLVM IR is like the code below.
The code doesn’t compile since the target sm version is higher than ptx version

How can I change .version from 6.3 to 7.5?

.version 6.3
.target sm_75
.address_size 64

PTX version in LLVM is set to the minimum required version for the GPU variant you’re compiling for. See llvm/lib/Target/NVPTX/NVPTX.td for the mapping.

PTX version is controlled via a target feature. You can set the one you want by passing -mattr=+ptx70 (or whichever PTX version you need) to opt/llc.