sprinkle LIKELY() on pp_hot.c scope.c and some *.h

I've gone through pp_hot.c and scope.c and added LIKELY() or UNLIKELY()
to all conditionals where I understand the code well enough to know that
a particular branch is or isn't likely to be taken very often.

I also processed some of the .h files which contain commonly used macros.

1 files changed, 27 insertions, 27 deletions

diff --git a/scope.c b/scope.c
index de90b1d7f6..07f24b7998 100644
--- a/scope.c
+++ b/scope.c
@@ -88,7 +88,7 @@ void
 Perl_push_scope(pTHX)
 {
     dVAR;
-    if (PL_scopestack_ix == PL_scopestack_max) {
+    if (UNLIKELY(PL_scopestack_ix == PL_scopestack_max)) {
 	PL_scopestack_max = GROW(PL_scopestack_max);
 	Renew(PL_scopestack, PL_scopestack_max, I32);
 #ifdef DEBUGGING
@@ -164,7 +164,7 @@ Perl_free_tmps(pTHX)
 #ifdef PERL_POISON
 	PoisonWith(PL_tmps_stack + PL_tmps_ix + 1, 1, SV *, 0xAB);
 #endif
-	if (sv && sv != &PL_sv_undef) {
+	if (LIKELY(sv && sv != &PL_sv_undef)) {
 	    SvTEMP_off(sv);
 	    SvREFCNT_dec_NN(sv);		/* note, can modify tmps_ix!!! */
 	}
@@ -214,7 +214,7 @@ Perl_save_scalar(pTHX_ GV *gv)
 
     PERL_ARGS_ASSERT_SAVE_SCALAR;
 
-    if (SvGMAGICAL(*sptr)) {
+    if (UNLIKELY(SvGMAGICAL(*sptr))) {
         PL_localizing = 1;
         (void)mg_get(*sptr);
         PL_localizing = 0;
@@ -321,13 +321,13 @@ Perl_save_ary(pTHX_ GV *gv)
 
     PERL_ARGS_ASSERT_SAVE_ARY;
 
-    if (!AvREAL(oav) && AvREIFY(oav))
+    if (UNLIKELY(!AvREAL(oav) && AvREIFY(oav)))
 	av_reify(oav);
     save_pushptrptr(SvREFCNT_inc_simple_NN(gv), oav, SAVEt_AV);
 
     GvAV(gv) = NULL;
     av = GvAVn(gv);
-    if (SvMAGIC(oav))
+    if (UNLIKELY(SvMAGIC(oav)))
 	mg_localize(MUTABLE_SV(oav), MUTABLE_SV(av), TRUE);
     return av;
 }
@@ -346,7 +346,7 @@ Perl_save_hash(pTHX_ GV *gv)
 
     GvHV(gv) = NULL;
     hv = GvHVn(gv);
-    if (SvMAGIC(ohv))
+    if (UNLIKELY(SvMAGIC(ohv)))
 	mg_localize(MUTABLE_SV(ohv), MUTABLE_SV(hv), TRUE);
     return hv;
 }
@@ -400,7 +400,7 @@ Perl_save_int(pTHX_ int *intp)
 
     PERL_ARGS_ASSERT_SAVE_INT;
 
-    if ((int)(type >> SAVE_TIGHT_SHIFT) != i) {
+    if (UNLIKELY((int)(type >> SAVE_TIGHT_SHIFT) != i)) {
         SS_ADD_INT(i);
         type = SAVEt_INT;
         size++;
@@ -447,7 +447,7 @@ Perl_save_I32(pTHX_ I32 *intp)
 
     PERL_ARGS_ASSERT_SAVE_I32;
 
-    if ((I32)(type >> SAVE_TIGHT_SHIFT) != i) {
+    if (UNLIKELY((I32)(type >> SAVE_TIGHT_SHIFT) != i)) {
         SS_ADD_INT(i);
         type = SAVEt_I32;
         size++;
@@ -559,7 +559,7 @@ Perl_save_clearsv(pTHX_ SV **svp)
 
     ASSERT_CURPAD_ACTIVE("save_clearsv");
     SvPADSTALE_off(*svp); /* mark lexical as active */
-    if ((offset_shifted >> SAVE_TIGHT_SHIFT) != offset) {
+    if (UNLIKELY((offset_shifted >> SAVE_TIGHT_SHIFT) != offset)) {
 	Perl_croak(aTHX_ "panic: pad offset %"UVuf" out of range (%p-%p)",
 		   offset, svp, PL_curpad);
     }
@@ -681,7 +681,7 @@ Perl_save_aelem_flags(pTHX_ AV *av, SSize_t idx, SV **sptr,
     SS_ADD_END(4);
     /* The array needs to hold a reference count on its new element, so it
        must be AvREAL. */
-    if (!AvREAL(av) && AvREIFY(av))
+    if (UNLIKELY(!AvREAL(av) && AvREIFY(av)))
 	av_reify(av);
     save_scalar_at(sptr, flags); /* XXX - FIXME - see #60360 */
     if (flags & SAVEf_KEEPOLDELEM)
@@ -691,7 +691,7 @@ Perl_save_aelem_flags(pTHX_ AV *av, SSize_t idx, SV **sptr,
      * won't actually be stored in the array - so it won't get
      * reaped when the localize ends. Ensure it gets reaped by
      * mortifying it instead. DAPM */
-    if (SvTIED_mg((const SV *)av, PERL_MAGIC_tied))
+    if (UNLIKELY(SvTIED_mg((const SV *)av, PERL_MAGIC_tied)))
 	sv_2mortal(sv);
 }
 
@@ -720,7 +720,7 @@ Perl_save_helem_flags(pTHX_ HV *hv, SV *key, SV **sptr, const U32 flags)
      * won't actually be stored in the hash - so it won't get
      * reaped when the localize ends. Ensure it gets reaped by
      * mortifying it instead. DAPM */
-    if (SvTIED_mg((const SV *)hv, PERL_MAGIC_tied))
+    if (UNLIKELY(SvTIED_mg((const SV *)hv, PERL_MAGIC_tied)))
 	sv_2mortal(sv);
 }
 
@@ -745,7 +745,7 @@ Perl_save_alloc(pTHX_ I32 size, I32 pad)
     const UV elems = 1 + ((size + pad - 1) / sizeof(*PL_savestack));
     const UV elems_shifted = elems << SAVE_TIGHT_SHIFT;
 
-    if ((elems_shifted >> SAVE_TIGHT_SHIFT) != elems)
+    if (UNLIKELY((elems_shifted >> SAVE_TIGHT_SHIFT) != elems))
 	Perl_croak(aTHX_
             "panic: save_alloc elems %"UVuf" out of range (%"IVdf"-%"IVdf")",
 		   elems, (IV)size, (IV)pad);
@@ -798,7 +798,7 @@ Perl_leave_scope(pTHX_ I32 base)
     arg1.any_ptr = NULL;
     arg2.any_ptr = NULL;
 
-    if (base < -1)
+    if (UNLIKELY(base < -1))
 	Perl_croak(aTHX_ "panic: corrupt saved stack index %ld", (long) base);
     DEBUG_l(Perl_deb(aTHX_ "savestack: releasing items %ld -> %ld\n",
 			(long)PL_savestack_ix, (long)base));
@@ -833,7 +833,7 @@ Perl_leave_scope(pTHX_ I32 base)
 	switch (type) {
 	case SAVEt_ITEM:			/* normal string */
 	    sv_replace(ARG1_SV, ARG0_SV);
-            if (SvSMAGICAL(ARG1_SV)) {
+            if (UNLIKELY(SvSMAGICAL(ARG1_SV))) {
                 PL_localizing = 2;
                 mg_set(ARG1_SV);
                 PL_localizing = 0;
@@ -855,7 +855,7 @@ Perl_leave_scope(pTHX_ I32 base)
 	    SV * const sv = *svp;
 	    *svp = ARG0_SV;
 	    SvREFCNT_dec(sv);
-            if (SvSMAGICAL(ARG0_SV)) {
+            if (UNLIKELY(SvSMAGICAL(ARG0_SV))) {
                 PL_localizing = 2;
                 mg_set(ARG0_SV);
                 PL_localizing = 0;
@@ -913,7 +913,7 @@ Perl_leave_scope(pTHX_ I32 base)
 	case SAVEt_AV:				/* array reference */
 	    SvREFCNT_dec(GvAV(ARG1_GV));
 	    GvAV(ARG1_GV) = ARG0_AV;
-            if (SvSMAGICAL(ARG0_SV)) {
+            if (UNLIKELY(SvSMAGICAL(ARG0_SV))) {
                 PL_localizing = 2;
                 mg_set(ARG0_SV);
                 PL_localizing = 0;
@@ -923,7 +923,7 @@ Perl_leave_scope(pTHX_ I32 base)
 	case SAVEt_HV:				/* hash reference */
 	    SvREFCNT_dec(GvHV(ARG1_GV));
 	    GvHV(ARG1_GV) = ARG0_HV;
-            if (SvSMAGICAL(ARG0_SV)) {
+            if (UNLIKELY(SvSMAGICAL(ARG0_SV))) {
                 PL_localizing = 2;
                 mg_set(ARG0_SV);
                 PL_localizing = 0;
@@ -944,7 +944,7 @@ Perl_leave_scope(pTHX_ I32 base)
 #ifdef NO_TAINT_SUPPORT
             PERL_UNUSED_VAR(was);
 #else
-	    if (ARG0_PTR == &(TAINT_get)) {
+	    if (UNLIKELY(ARG0_PTR == &(TAINT_get))) {
 		/* If we don't update <was>, to reflect what was saved on the
 		 * stack for PL_tainted, then we will overwrite this attempt to
 		 * restore it when we exit this routine.  Note that this won't
@@ -1154,12 +1154,12 @@ Perl_leave_scope(pTHX_ I32 base)
 	    break;
 	case SAVEt_AELEM:		/* array element */
 	    svp = av_fetch(ARG2_AV, arg1.any_iv, 1);
-	    if (!AvREAL(ARG2_AV) && AvREIFY(ARG2_AV)) /* undo reify guard */
+	    if (UNLIKELY(!AvREAL(ARG2_AV) && AvREIFY(ARG2_AV))) /* undo reify guard */
 		SvREFCNT_dec(ARG0_SV);
-	    if (svp) {
+	    if (LIKELY(svp)) {
 		SV * const sv = *svp;
-		if (sv && sv != &PL_sv_undef) {
-		    if (SvTIED_mg((const SV *)ARG2_AV, PERL_MAGIC_tied))
+		if (LIKELY(sv && sv != &PL_sv_undef)) {
+		    if (UNLIKELY(SvTIED_mg((const SV *)ARG2_AV, PERL_MAGIC_tied)))
 			SvREFCNT_inc_void_NN(sv);
                     refsv = ARG2_SV;
 		    goto restore_sv;
@@ -1172,11 +1172,11 @@ Perl_leave_scope(pTHX_ I32 base)
         {
 	    HE * const he = hv_fetch_ent(ARG2_HV, ARG1_SV, 1, 0);
 	    SvREFCNT_dec(ARG1_SV);
-	    if (he) {
+	    if (LIKELY(he)) {
 		const SV * const oval = HeVAL(he);
-		if (oval && oval != &PL_sv_undef) {
+		if (LIKELY(oval && oval != &PL_sv_undef)) {
 		    svp = &HeVAL(he);
-		    if (SvTIED_mg((const SV *)ARG2_HV, PERL_MAGIC_tied))
+		    if (UNLIKELY(SvTIED_mg((const SV *)ARG2_HV, PERL_MAGIC_tied)))
 			SvREFCNT_inc_void(*svp);
 		    refsv = ARG2_SV; /* what to refcnt_dec */
 		    goto restore_sv;
@@ -1215,7 +1215,7 @@ Perl_leave_scope(pTHX_ I32 base)
 	    break;
 	case SAVEt_COMPPAD:
 	    PL_comppad = (PAD*)ARG0_PTR;
-	    if (PL_comppad)
+	    if (LIKELY(PL_comppad))
 		PL_curpad = AvARRAY(PL_comppad);
 	    else
 		PL_curpad = NULL;