STINNER Victor added the comment: Serhiy: "Since almost all calls of PyEval_EvalFrameEx() are in the same file as its definition, I suppose the compiler can inline it even without PGO."
Let me check. My patch changes gen_send_ex() of genobject.c and _PyEval_EvalCodeWithName() of ceval.c. "gcc -O3" is able to inline PyEval_EvalFrameEx() in the same file (ceval.c), but not in a different file (genobject.c). My patch also avoids an useless call to PyThreadState_GET()... Well, I'm not sure that it's worth it. I propose the change because the indirection now looks completely useless to me, but I didn't expect that it could break anything. With my patch, python-gdb.py is fixed. Steve says that Visual Studio is already fixed as well. So I don't know, it's up to you ;-) -- gen_send_ex(). C code: 188 gen->gi_running = 1; 189 result = PyEval_EvalFrameEx(f, exc); 190 gen->gi_running = 0; x86_64 assembler (gcc -03): => 0x000000000047fe37 <gen_iternext+103>: movb $0x1,0x18(%rbp) 0x000000000047fe3b <gen_iternext+107>: callq 0x54b870 <PyEval_EvalFrameEx> 0x000000000047fe40 <gen_iternext+112>: movb $0x0,0x18(%rbp) 0x000000000047fe44 <gen_iternext+116>: mov %rax,%r12 0x000000000047fe47 <gen_iternext+119>: mov 0x18(%rbx),%rdi I still see the call to PyEval_EvalFrameEx(). -- _PyEval_EvalCodeWithName(). C code: 4169 retval = PyEval_EvalFrameEx(f,0); x86_64 assembler (gcc -03): => 0x000000000054ae30 <+2544>: mov 0x3827f9(%rip),%rax # 0x8cd630 <_PyThreadState_Current> 0x000000000054ae37 <+2551>: xor %esi,%esi 0x000000000054ae39 <+2553>: mov 0x40(%rsp),%rdi 0x000000000054ae3e <+2558>: mov 0x10(%rax),%rax 0x000000000054ae42 <+2562>: callq *0x70(%rax) In this file, PyEval_EvalFrameEx() is inlined. I understand that the first instruction is the PyThreadState_GET() call which is an atomic read (single x86 instruction). My patch avoids the useless PyThreadState_GET(), since tstate must not change. ---------- _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue28924> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
