Re: [RFA/rfc] blockframe.c: dummy frames unwind and pseudoregs

[Elena Zannoni <ezannoni@redhat.com>]

Ok, I committed this:
Index: blockframe.c
===================================================================
RCS file: /cvs/uberbaum/gdb/blockframe.c,v
retrieving revision 1.37
diff -u -p -r1.37 blockframe.c
--- blockframe.c	18 Aug 2002 22:40:15 -0000	1.37
+++ blockframe.c	22 Aug 2002 22:23:15 -0000
@@ -1402,11 +1402,10 @@ generic_call_dummy_register_unwind (stru
 #endif
       gdb_assert (registers != NULL);
       /* Return the actual value.  */
-      /* FIXME: cagney/2002-06-26: This should be via the
-         gdbarch_register_read() method so that it, on the fly,
+      /* Use the regcache_cooked_read() method so that it, on the fly,
          constructs either a raw or pseudo register from the raw
          register cache.  */
-      regcache_raw_read (registers, regnum, bufferp);
+      regcache_cooked_read (registers, regnum, bufferp);
     }
 }
 



Andrew Cagney writes:
 > 
 > > This is because the generic_call_dummy_register_unwind() doesn't deal with
 > > pseudo registers. It has this comment:
 > > 
 > >       /* Return the actual value.  */
 > >       /* FIXME: cagney/2002-06-26: This should be via the
 > >          gdbarch_register_read() method so that it, on the fly,
 > >          constructs either a raw or pseudo register from the raw
 > >          register cache.  */
 > >       regcache_raw_read (registers, regnum, bufferp);
 > > 
 > > 
 > > If instead of raw reads I do cooked reads, I don't get the error.  I
 > > wonder though if, based of the comment, this could be a problem for
 > > other targets.
 > > Thoughts?
 > 
 > Two architecture features could cause problems:
 > - where an architecture has different sized raw and virtual (pre-cursor 
 > to cooked) registers
 > - where there are pseudo registers
 > 
 > MIPS has has different sized raw and virtual registers and, suprise!, 
 > doesn't use the code in question.
 > 
 > That code block definitly needs to read the cooked value.  The only 
 > potential problem is with:
 > http://sources.redhat.com/ml/gdb/2002-08/msg00196.html
 > and there, I think your case adds support to the argument that the dummy 
 > frame code should save (readonly) cooked values.
 > 
 > Given this, yes, ok.
 > 
 > BTW, don't forget to update the comment :-)
 > 
 > Andrew
 > 
 > 
 > 
 > > 2002-08-22  Elena Zannoni  <ezannoni@redhat.com>
 > > 
 > > 	* blockframe.c (generic_call_dummy_register_unwind): Use
 > > 	regcache_cooked_read to catch cases in which the variable is
 > > 	stored in a pseudo register.
 > > 
 > > Index: blockframe.c
 > > ===================================================================
 > > RCS file: /cvs/uberbaum/gdb/blockframe.c,v
 > > retrieving revision 1.37
 > > diff -u -p -r1.37 blockframe.c
 > > --- blockframe.c	18 Aug 2002 22:40:15 -0000	1.37
 > > +++ blockframe.c	22 Aug 2002 15:35:27 -0000
 > > @@ -1406,7 +1406,7 @@ generic_call_dummy_register_unwind (stru
 > >           gdbarch_register_read() method so that it, on the fly,
 > >           constructs either a raw or pseudo register from the raw
 > >           register cache.  */
 > > -      regcache_raw_read (registers, regnum, bufferp);
 > > +      regcache_cooked_read (registers, regnum, bufferp);
 > >      }
 > >  }
 > > 
 >