On Thu, Feb 04, 2021 at 07:29:02PM +0100, Philippe Mathieu-Daudé wrote: > The code is currently comparing c2 to the type promotion of > uint32_t and int32_t. That is, the conversion rules are as: > > (common_type) c2 == (common_type) (uint32_t) > (is_unsigned > ? (uint32_t)c2 > : (uint32_t)(int32_t)c2) > > In the signed case we lose the desired sign extensions because > of the argument promotion rules of the ternary operator. > > Solve the problem by doing the round-trip parsing through the > intermediate type and back to the desired common type (all at > one expression). > > Fixes: a534bb15f30 ("tcg/s390: Use constant pool for cmpi") > Reported-by: Miroslav Rezanina <mreza...@redhat.com> > Reported-by: Richard W.M. Jones <rjo...@redhat.com> > Suggested-by: David Hildenbrand <da...@redhat.com> > Suggested-by: Eric Blake <ebl...@redhat.com> > Signed-off-by: Philippe Mathieu-Daudé <f4...@amsat.org> > --- > tcg/s390/tcg-target.c.inc | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/tcg/s390/tcg-target.c.inc b/tcg/s390/tcg-target.c.inc > index b67470137c4..695d7ee6523 100644 > --- a/tcg/s390/tcg-target.c.inc > +++ b/tcg/s390/tcg-target.c.inc > @@ -1067,7 +1067,7 @@ static int tgen_cmp(TCGContext *s, TCGType type, > TCGCond c, TCGReg r1, > op = (is_unsigned ? RIL_CLFI : RIL_CFI); > tcg_out_insn_RIL(s, op, r1, c2); > goto exit; > - } else if (c2 == (is_unsigned ? (uint32_t)c2 : (int32_t)c2)) { > + } else if (c2 == (is_unsigned ? (TCGArg)(uint32_t)c2 : > (TCGArg)(int32_t)c2)) { > op = (is_unsigned ? RIL_CLGFI : RIL_CGFI); > tcg_out_insn_RIL(s, op, r1, c2); > goto exit;
I have tested this patch on an s390x host on top of 1ed9228f63e "Merge remote-tracking branch 'remotes/ericb/tags/pull-nbd-2021-02-02-v2' into staging" and I can confirm that it fixes both previously reported problems. Therefore you can add: Tested-by: Richard W.M. Jones <rjo...@redhat.com> Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com libguestfs lets you edit virtual machines. Supports shell scripting, bindings from many languages. http://libguestfs.org