llvm-project

dfadcdfa - [SystemZ][z/OS] Reorder checks needConversion and shouldUseMmap. (#240900)

[SystemZ][z/OS] Reorder checks needConversion and shouldUseMmap. (#240900) Reorder the two checks and also remove return false on z/OS in shouldUseMmap, so binary files can be memory-mapped on z/OS. This fixes llvm/unittests/Support/MemoryBufferTest.cpp which is currently failing on z/OS.