Move herelines out of the lex_shared struct

Previously, the line number was localised in lexing scopes.  herelines
had to be in the lex_shared struct so that inner lexing scopes
could peek into values belonging to outer lexing scopes and set the
herelines value belonging to the same scope that a here-doc body was
extracted from.  (herelines records how much extra to increase the
line number at the next line ending, to jump over a here-doc.)

In commit ffdb8b167e, I changed things so that lexing scopes no longer
localised the line number, except for here-docs, and the line number
was incremented within the inner lexing scope, instead of during the
initial scan for the terminator.  That meant the herelines value had
to be copied into the inner lexing scope.

For nested here-docs, the inner here-doc’s body is always inside the
outer here-doc, so no peeking into outer scopes is necessary.

Hence, there is no longer any reason for herelines to be inside the
lex_shared struct.  We can put it directly inside the parser struct.
Here-docs will localise it.  Other quote-like constructs will not (and
can avoid the copy.)

2 files changed, 19 insertions, 24 deletions

diff --git a/parser.h b/parser.h
index dc5e89df4d..4453e5852b 100644
--- a/parser.h
+++ b/parser.h
@@ -29,7 +29,6 @@ typedef struct yy_lexshared {
     char		*ls_bufptr;	/* mirrors PL_parser->bufptr */
     char		*re_eval_start;	/* start of "(?{..." text */
     SV			*re_eval_str;	/* "(?{...})" text */
-    line_t		herelines;	/* number of lines in here-doc */
 } LEXSHARED;
 
 typedef struct yy_parser {
@@ -123,7 +122,7 @@ typedef struct yy_parser {
 
     COP		*saved_curcop;	/* the previous PL_curcop */
     char	tokenbuf[256];
-
+    line_t	herelines;	/* number of lines in here-doc */
     U8		lex_fakeeof;	/* precedence at which to fake EOF */
     U8		lex_flags;
     PERL_BITFIELD16	in_pod:1;      /* lexer is within a =pod section */
diff --git a/toke.c b/toke.c
index 31d346c012..2e582e4eba 100644
--- a/toke.c
+++ b/toke.c
@@ -303,9 +303,9 @@ static const char* const lex_state_names[] = {
 #define COPLINE_INC_WITH_HERELINES		    \
     STMT_START {				     \
 	CopLINE_inc(PL_curcop);			      \
-	if (PL_parser->lex_shared->herelines)	       \
-	    CopLINE(PL_curcop) += PL_parser->lex_shared->herelines, \
-	    PL_parser->lex_shared->herelines = 0;		     \
+	if (PL_parser->herelines)		       \
+	    CopLINE(PL_curcop) += PL_parser->herelines, \
+	    PL_parser->herelines = 0;			 \
     } STMT_END
 /* Called after scan_str to update CopLINE(PL_curcop), but only when there
  * is no sublex_push to follow. */
@@ -313,7 +313,7 @@ static const char* const lex_state_names[] = {
     STMT_START {			       \
 	CopLINE_set(PL_curcop, PL_multi_end);	\
 	if (PL_multi_end != PL_multi_start)	 \
-	    PL_parser->lex_shared->herelines = 0; \
+	    PL_parser->herelines = 0;		  \
     } STMT_END
 
 
@@ -1569,7 +1569,7 @@ Perl_lex_read_space(pTHX_ U32 flags)
 		break;
 	    PL_parser->bufptr = s;
 	    l = CopLINE(PL_curcop);
-	    CopLINE(PL_curcop) += PL_parser->lex_shared->herelines + 1;
+	    CopLINE(PL_curcop) += PL_parser->herelines + 1;
 	    got_more = lex_next_chunk(flags);
 	    CopLINE_set(PL_curcop, l);
 	    s = PL_parser->bufptr;
@@ -2613,6 +2613,8 @@ S_sublex_push(pTHX)
     {
 	SAVECOPLINE(PL_curcop);
 	SAVEI32(PL_multi_end);
+	SAVEI32(PL_parser->herelines);
+	PL_parser->herelines = 0;
     }
     SAVEI8(PL_multi_close);
     SAVEPPTR(PL_bufptr);
@@ -2665,10 +2667,6 @@ S_sublex_push(pTHX)
     Newxz(shared, 1, LEXSHARED);
     shared->ls_prev = PL_parser->lex_shared;
     PL_parser->lex_shared = shared;
-    if (!is_heredoc && PL_multi_start != PL_multi_end) {
-	shared->herelines = shared->ls_prev->herelines;
-	shared->ls_prev->herelines = 0;
-    }
 
     PL_lex_inwhat = PL_sublex_info.sub_inwhat;
     if (PL_lex_inwhat == OP_TRANSR) PL_lex_inwhat = OP_TRANS;
@@ -2736,8 +2734,8 @@ S_sublex_done(pTHX)
 	if (SvTYPE(PL_linestr) >= SVt_PVNV) {
 	    CopLINE(PL_curcop) +=
 		((XPVNV*)SvANY(PL_linestr))->xnv_u.xpad_cop_seq.xlow
-		 + PL_parser->lex_shared->herelines;
-	    PL_parser->lex_shared->herelines = 0;
+		 + PL_parser->herelines;
+	    PL_parser->herelines = 0;
 	}
 	return ',';
     }
@@ -2759,7 +2757,7 @@ S_sublex_done(pTHX)
 #endif
 	LEAVE;
 	if (PL_multi_close == '<')
-	    PL_parser->lex_shared->herelines += l - PL_multi_end;
+	    PL_parser->herelines += l - PL_multi_end;
 	PL_bufend = SvPVX(PL_linestr);
 	PL_bufend += SvCUR(PL_linestr);
 	PL_expect = XOPERATOR;
@@ -10044,7 +10042,7 @@ S_scan_heredoc(pTHX_ char *s)
 	SvIV_set(tmpstr, '\\');
     }
 
-    PL_multi_start = origline + 1;
+    PL_multi_start = origline + 1 + PL_parser->herelines;
     PL_multi_open = PL_multi_close = '<';
     /* inside a string eval or quote-like operator */
     if (!infile || PL_lex_inwhat) {
@@ -10085,14 +10083,13 @@ S_scan_heredoc(pTHX_ char *s)
 	    s = (char*)memchr((void*)s, '\n', PL_bufend - s);
 	    assert(s);
 	}
-	PL_multi_start += shared->herelines;
 	linestr = shared->ls_linestr;
 	bufend = SvEND(linestr);
 	d = s;
 	while (s < bufend - len + 1 &&
           memNE(s,PL_tokenbuf,len) ) {
 	    if (*s++ == '\n')
-		++shared->herelines;
+		++PL_parser->herelines;
 	}
 	if (s >= bufend - len + 1) {
 	    goto interminable;
@@ -10109,7 +10106,7 @@ S_scan_heredoc(pTHX_ char *s)
 #endif
 	s += len - 1;
 	/* the preceding stmt passes a newline */
-	shared->herelines++;
+	PL_parser->herelines++;
 
 	/* s now points to the newline after the heredoc terminator.
 	   d points to the newline before the body of the heredoc.
@@ -10148,7 +10145,6 @@ S_scan_heredoc(pTHX_ char *s)
     {
       SV *linestr_save;
      streaming:
-      PL_multi_start += shared->herelines;
       sv_setpvs(tmpstr,"");   /* avoid "uninitialized" warning */
       term = PL_tokenbuf[1];
       len--;
@@ -10168,7 +10164,7 @@ S_scan_heredoc(pTHX_ char *s)
 #endif
 	PL_bufptr = PL_bufend;
 	CopLINE_set(PL_curcop,
-		    origline + 1 + shared->herelines);
+		    origline + 1 + PL_parser->herelines);
 	if (!lex_next_chunk(LEX_NO_TERM)
 	 && (!SvCUR(tmpstr) || SvEND(tmpstr)[-1] != '\n')) {
 	    SvREFCNT_dec(linestr_save);
@@ -10186,7 +10182,7 @@ S_scan_heredoc(pTHX_ char *s)
 #ifdef PERL_MAD
 	stuffstart = s - SvPVX(PL_linestr);
 #endif
-	shared->herelines++;
+	PL_parser->herelines++;
 	PL_last_lop = PL_last_uni = NULL;
 #ifndef PERL_STRICT_CR
 	if (PL_bufend - PL_linestart >= 2) {
@@ -10216,7 +10212,7 @@ S_scan_heredoc(pTHX_ char *s)
 	}
       }
     }
-    PL_multi_end = origline + shared->herelines;
+    PL_multi_end = origline + PL_parser->herelines;
     if (SvCUR(tmpstr) + 5 < SvLEN(tmpstr)) {
 	SvPV_shrink_to_cur(tmpstr);
     }
@@ -10504,7 +10500,7 @@ S_scan_str(pTHX_ char *start, int keep_quoted, int keep_delims, int re_reparse,
     /* mark where we are */
     PL_multi_start = CopLINE(PL_curcop);
     PL_multi_open = term;
-    herelines = PL_parser->lex_shared->herelines;
+    herelines = PL_parser->herelines;
 
     /* find corresponding closing delimiter */
     if (term && (tmps = strchr("([{< )]}> )]}>",term)))
@@ -10859,7 +10855,7 @@ S_scan_str(pTHX_ char *start, int keep_quoted, int keep_delims, int re_reparse,
 
     PL_multi_end = CopLINE(PL_curcop);
     CopLINE_set(PL_curcop, PL_multi_start);
-    PL_parser->lex_shared->herelines = herelines;
+    PL_parser->herelines = herelines;
 
     /* if we allocated too much space, give some back */
     if (SvCUR(sv) + 5 < SvLEN(sv)) {