08.12.2015 13:39, Vlad Khorsun wrote: > I don't know how to guarantee atomic execution of sequence of two > instructions on Intel HW.
Don't be confused by pseudocode in function description. > You have a proof of course... Test program from your link. MSVC assembler: > ; Line 7 > mov DWORD PTR _cur$[esp+8], 15 ; 0000000fH > push esi > ; Line 9 - old = _InterlockedOr(&cur, 0xF0); > mov ecx, 240 ; 000000f0H > lea edx, DWORD PTR _cur$[esp+12] > mov eax, DWORD PTR [edx] > $LN3@main: > mov esi, eax > or esi, ecx > lock cmpxchg DWORD PTR [edx], esi > jne SHORT $LN3@main > mov DWORD PTR _old$[esp+12], eax > ; Line 10 - _InterlockedOr(&cur, 0xF0); > mov eax, edx > lock or DWORD PTR [eax], ecx GCC assembler: > movl $15, 44(%rsp) > ; old = __atomic_fetch_or(&cur, 0xF0, __ATOMIC_SEQ_CST); > movl 44(%rsp), %eax > .L2: > movl %eax, %edx > movl %eax, %ecx > orb $-16, %dl > lock cmpxchgl %edx, 44(%rsp) > jne .L2 > movl %ecx, 40(%rsp) > ; __atomic_fetch_or(&cur, 0xF0, __ATOMIC_SEQ_CST); > lock orl $240, 44(%rsp) -- WBR, SD. ------------------------------------------------------------------------------ Go from Idea to Many App Stores Faster with Intel(R) XDK Give your users amazing mobile app experiences with Intel(R) XDK. Use one codebase in this all-in-one HTML5 development environment. Design, debug & build mobile apps & 2D/3D high-impact games for multiple OSs. http://pubads.g.doubleclick.net/gampad/clk?id=254741911&iu=/4140 Firebird-Devel mailing list, web interface at https://lists.sourceforge.net/lists/listinfo/firebird-devel
