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| author | Steffen Mueller <smueller@cpan.org> | 2012-10-22 20:56:45 +0200 |
|---|---|---|
| committer | Steffen Mueller <smueller@cpan.org> | 2012-10-22 20:56:45 +0200 |
| commit | 2102d7a2adc27f86a21271a4721de2799b5158a0 (patch) | |
| tree | a0ad9894b9a21ac7ce25f1b6fe50590f362c187b /universal.c | |
| parent | 855ea7c74bf7bb29e7655147ec501fcdb53b07cd (diff) | |
| download | perl-2102d7a2adc27f86a21271a4721de2799b5158a0.tar.gz | |
Move more X's off the PUSH into EXTEND's
Generally speaking, if there's branching and each branch may contain a
varying number of PUSH operations, EXTENDing to the longest number of
items should generally be more efficient since the stack will eventually
grow to a relatively steady state, but the extra branching incurred by
the X's will cost every time.
Diffstat (limited to 'universal.c')
| -rw-r--r-- | universal.c | 23 |
1 files changed, 13 insertions, 10 deletions
diff --git a/universal.c b/universal.c index 9f632eee3e..055d8ab176 100644 --- a/universal.c +++ b/universal.c @@ -1035,40 +1035,41 @@ XS(XS_PerlIO_get_layers) const bool argok = argsvp && *argsvp && SvPOK(*argsvp); const bool flgok = flgsvp && *flgsvp && SvIOK(*flgsvp); + EXTEND(SP, 3); /* Three is the max in all branches: better check just once */ if (details) { /* Indents of 5? Yuck. */ /* We know that PerlIO_get_layers creates a new SV for the name and flags, so we can just take a reference and "steal" it when we free the AV below. */ - XPUSHs(namok + PUSHs(namok ? sv_2mortal(SvREFCNT_inc_simple_NN(*namsvp)) : &PL_sv_undef); - XPUSHs(argok + PUSHs(argok ? newSVpvn_flags(SvPVX_const(*argsvp), SvCUR(*argsvp), (SvUTF8(*argsvp) ? SVf_UTF8 : 0) | SVs_TEMP) : &PL_sv_undef); - XPUSHs(flgok + PUSHs(flgok ? sv_2mortal(SvREFCNT_inc_simple_NN(*flgsvp)) : &PL_sv_undef); nitem += 3; } else { if (namok && argok) - XPUSHs(sv_2mortal(Perl_newSVpvf(aTHX_ "%"SVf"(%"SVf")", + PUSHs(sv_2mortal(Perl_newSVpvf(aTHX_ "%"SVf"(%"SVf")", SVfARG(*namsvp), SVfARG(*argsvp)))); else if (namok) - XPUSHs(sv_2mortal(SvREFCNT_inc_simple_NN(*namsvp))); + PUSHs(sv_2mortal(SvREFCNT_inc_simple_NN(*namsvp))); else - XPUSHs(&PL_sv_undef); + PUSHs(&PL_sv_undef); nitem++; if (flgok) { const IV flags = SvIVX(*flgsvp); if (flags & PERLIO_F_UTF8) { - XPUSHs(newSVpvs_flags("utf8", SVs_TEMP)); + PUSHs(newSVpvs_flags("utf8", SVs_TEMP)); nitem++; } } @@ -1234,13 +1235,14 @@ XS(XS_re_regnames) av = MUTABLE_AV(SvRV(ret)); length = av_len(av); + EXTEND(SP, length+1); /* better extend stack just once */ for (i = 0; i <= length; i++) { entry = av_fetch(av, i, FALSE); if (!entry) Perl_croak(aTHX_ "NULL array element in re::regnames()"); - mXPUSHs(SvREFCNT_inc_simple_NN(*entry)); + mPUSHs(SvREFCNT_inc_simple_NN(*entry)); } SvREFCNT_dec(ret); @@ -1311,8 +1313,9 @@ XS(XS_re_regexp_pattern) (RX_UTF8(re) ? SVf_UTF8 : 0) | SVs_TEMP); /* return the pattern and the modifiers */ - XPUSHs(pattern); - XPUSHs(newSVpvn_flags(reflags, left, SVs_TEMP)); + EXTEND(SP, 2); + PUSHs(pattern); + PUSHs(newSVpvn_flags(reflags, left, SVs_TEMP)); XSRETURN(2); } else { /* Scalar, so use the string that Perl would return */ |