nasm/test/nop.asm

;Testname=unoptimized; Arguments=-fbin -onop.bin;     Files=.stdout .stderr nop.bin
;Testname=optimized;   Arguments=-fbin -onop.bin -Ox; Files=.stdout .stderr nop.bin

	bits 64

	nop
	o64 nop
	pause
	o64 pause

	xchg ax,ax
	xchg eax,eax
	xchg rax,rax
	
	rep xchg ax,ax
	rep xchg eax,eax
	rep xchg rax,rax
Configure tests to be performed automatically 2008-04-23 13:05:31 +00:00			`;Testname=unoptimized; Arguments=-fbin -onop.bin; Files=.stdout .stderr nop.bin`
			`;Testname=optimized; Arguments=-fbin -onop.bin -Ox; Files=.stdout .stderr nop.bin`

Un-special-case "xchg rax,rax"; disassemble o64 Un-special-case "xchg rax,rax"; allow it to be encoded as 48 90 for orthogonality's sake. It's a no-op, to be sure, but so are many other instructions. "xchg eax,eax" is still special-cased in 64-bit mode since it is not a no-op; unadorned opcode 90 is now simply "nop" and nothing else. Make the disassembler detect unused REX.W and display them as an "o64" prefix. 2007-11-13 06:55:27 +00:00			`bits 64`

			`nop`
			`o64 nop`
			`pause`
			`o64 pause`

			`xchg ax,ax`
			`xchg eax,eax`
			`xchg rax,rax`

			`rep xchg ax,ax`
			`rep xchg eax,eax`
			`rep xchg rax,rax`