Chris Lattner de87d146ab Implement Regression/CodeGen/X86/rotate.ll: emit rotate instructions (which ... typically cost 1 cycle) instead of shld/shrd instruction (which are typically 6 or more cycles). This also saves code space. For example, instead of emitting: rotr: mov %EAX, DWORD PTR [%ESP + 4] mov %CL, BYTE PTR [%ESP + 8] shrd %EAX, %EAX, %CL ret rotli: mov %EAX, DWORD PTR [%ESP + 4] shrd %EAX, %EAX, 27 ret Emit: rotr32: mov %CL, BYTE PTR [%ESP + 8] mov %EAX, DWORD PTR [%ESP + 4] ror %EAX, %CL ret rotli32: mov %EAX, DWORD PTR [%ESP + 4] ror %EAX, 27 ret We also emit byte rotate instructions which do not have a sh[lr]d counterpart at all. llvm-svn: 19692		2005-01-19 08:07:05 +00:00
llvm	Implement Regression/CodeGen/X86/rotate.ll: emit rotate instructions (which	2005-01-19 08:07:05 +00:00