From: Markus <markus@...>
Date: 2004-10-26T14:39:47+09:00
Subject: Re: Errors in line numbers reported?

On Mon, 2004-10-25 at 20:54, Ara.T.Howard@noaa.gov wrote:
> On Tue, 26 Oct 2004, Yukihiro Matsumoto wrote:
> 
> > Hi,
> >
> > In message "Re: Errors in line numbers reported?"
> >    on Tue, 26 Oct 2004 11:34:05 +0900, Ara.T.Howard@noaa.gov writes:
> >
> > |> Send me, unless the source file is larger than 8191 lines.
> > |> It's implementation restriction.
> >
> > |you mean __LINE__ cannot go > that that?
> >
> > Unfortunately yes.  It's balance between performance and my
> > intelligence.  Maybe someone wiser than me can enlighten me.
> >
> > 							matz.
> 
> with a lead in like that you can't expect many patches can you?  ;-)
> 

     I agree with Ara; so instead I will sign up under the always
implicit "more foolhardy" clause in the hopes of learning a little by
claiming less.

     I have a patch (attached).  It removes the 8k line limit on error
tracking but increases the size of the RNODE to 36 bytes (if I calculate
correctly) from the easier to align 32 bytes.  I suspect that this is
where the performance hit would come from, but I have been unable to
measure any consistent speed difference between the patched and
unpatched versions, so I may not be testing the right cases.  It may
also be that the savings of not having to shift the bits around makes up
for the alignment hit somewhat, but I have not tested this idea.

            -- Markus

diff -u ruby-1.8.2/eval.c ruby-1.8.2-8klines/eval.c
--- ruby-1.8.2/eval.c	2004-07-27 23:32:37.000000000 -0700
+++ ruby-1.8.2-8klines/eval.c	2004-10-25 22:13:13.000000000 -0700
@@ -8296,7 +8296,7 @@
 
     Data_Get_Struct(self, struct BLOCK, data);
     if ((node = data->frame.node) || (node = data->body)) {
-	len += strlen(node->nd_file) + 2 +
(SIZEOF_LONG*CHAR_BIT-NODE_LSHIFT)/3;
+	len += strlen(node->nd_file) + 2 + (SIZEOF_LONG*CHAR_BIT)/3;
 	str = rb_str_new(0, len);
 	sprintf(RSTRING(str)->ptr, "#<%s:0x%.*lx@%s:%d>", cname, w,
(VALUE)data->body,
 		node->nd_file, nd_line(node));
diff -u ruby-1.8.2/node.h ruby-1.8.2-8klines/node.h
--- ruby-1.8.2/node.h	2004-10-25 22:05:16.000000000 -0700
+++ ruby-1.8.2-8klines/node.h	2004-10-25 22:20:04.000000000 -0700
@@ -130,6 +130,7 @@
 typedef struct RNode {
     unsigned long flags;
     char *nd_file;
+    unsigned long nd_line;
     union {
 	struct RNode *node;
 	ID id;
@@ -159,11 +160,8 @@
 #define nd_set_type(n,t) \
    
RNODE(n)->flags=((RNODE(n)->flags&~FL_UMASK)|(((t)<<FL_USHIFT)&FL_UMASK))
 
-#define NODE_LSHIFT (FL_USHIFT+8)
-#define NODE_LMASK  (((long)1<<(sizeof(NODE*)*CHAR_BIT-NODE_LSHIFT))-1)
-#define nd_line(n) ((unsigned
int)(((RNODE(n))->flags>>NODE_LSHIFT)&NODE_LMASK))
-#define nd_set_line(n,l) \
-   
RNODE(n)->flags=((RNODE(n)->flags&~(-1<<NODE_LSHIFT))|(((l)&NODE_LMASK)<<NODE_LSHIFT))
+#define nd_line(n) (((RNODE(n))->nd_line))
+#define nd_set_line(n,l) (RNODE(n)->nd_line=(l))
 
 #define nd_head  u1.node
 #define nd_alen  u2.argc