Re: [Valgrind-developers] another false positive?

[Julian S. <js...@ac...>]

Thanks for the logging info.  I was able to construct a test case from
it and the attached patch fixes it (I assume this is on x86-linux).
Can you try it?

J

Index: priv/guest-x86/ghelpers.c
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
=2D-- priv/guest-x86/ghelpers.c   (revision 1671)
+++ priv/guest-x86/ghelpers.c   (working copy)
@@ -1161,6 +1161,23 @@
             );
       }

+      if (isU32(cc_op, X86G_CC_OP_COPY) && isU32(cond, X86CondP)) {
+         /* COPY, then P --> extract P from dep1, and test (P =3D=3D 1). */
+         return
+            unop(
+               Iop_1Uto32,
+               binop(
+                  Iop_CmpNE32,
+                  binop(
+                     Iop_And32,
+                     binop(Iop_Shr32, cc_dep1, mkU8(X86G_CC_SHIFT_P)),
+                     mkU32(1)
+                  ),
+                  mkU32(0)
+               )
+            );
+      }
+
       return NULL;
    }




On Wednesday 01 November 2006 01:17, Rafael Esp=EDndola wrote:
> On 10/30/06, Julian Seward <js...@ac...> wrote:
> > I need to see the IR (internal intermediate representation) created for
> > these blocks.  Can you run with
> >
> > --tool=3Dnone --trace-flags=3D10001000 --vex-guest-chase-thresh=3D0
> > --trace-notbelow=3D0
> >
> > which will give you many megabytes of log file.  Then find and send the
> > presumably 3 blocks which pertain to this function.  The blocks in the
> > log have their function name + offset attached so it is easy to find
> > them.
>
> Attached.
>
> > Thanks.
> >
> > J
>
> My pleasure!
>
> Rafael