Interestingly the code you quoted is not called at all. I guess eventually linking phase removes it as dead code.
That considered, both pre- and post-increment generate identical code, even with VS2017.
This matches my previous experience about pretty much any compiler in last 15 years or so -- there's no difference between ++i and i++, unless, of course, it's in a statement and changes the actual meaning of code.
"it++" case. Note that iterator function is not called.
foo PROC
mov rdx, QWORD PTR [rcx]
xor eax, eax
mov rcx, QWORD PTR [rcx+8]
cmp rdx, rcx
je SHORT $LN70@foo
mov r8, rcx
sub r8, rdx
sar r8, 5
npad 8
$LL4@foo:
add rax, r8
add rdx, 32 ; 00000020H
cmp rdx, rcx
jne SHORT $LL4@foo
$LN70@foo:
ret 0
foo ENDP
Here's the code generated for "++it" case. Iterator function is not called here either.
foo PROC
mov rdx, QWORD PTR [rcx]
xor eax, eax
mov rcx, QWORD PTR [rcx+8]
cmp rdx, rcx
je SHORT $LN68@foo
mov r8, rcx
sub r8, rdx
sar r8, 5
npad 8
$LL4@foo:
add rax, r8
add rdx, 32 ; 00000020H
cmp rdx, rcx
jne SHORT $LL4@foo
$LN68@foo:
ret 0
foo ENDP
