> Date: Tue, 13 Sep 2016 00:49:51 +0200 > From: "Edgar E. Iglesias" <edgar.igles...@gmail.com> > On Mon, Sep 05, 2016 at 01:54:10PM +0200, Rabin Vincent wrote: > > From: Hans-Peter Nilsson <h...@axis.com> > > > > Don't count prefix instructions as separate when singlestepping. > > > > For example, for this following instruction > > > > 1ad8: a011 e00b move.d r0,[r1-96] > > > > before this patch, we get two register dumps: > > > > PC=1ad8 CCS=0 btaken=1 btarget=1ac6 > > cc_op=1 cc_src=3746 cc_dest=1 cc_result=ea2 cc_mask=0 > > $r0=00000000 $r1=00004360 $r2=00004308 $r3=0000026c > > $r4=00002076 $r5=00002022 $r6=00000000 $r7=00000000 > > $r8=00000000 $r9=00000ea2 $r10=00000002 $r11=00004308 > > $r12=00001080 $r13=00000ec0 $sp=0000bfd8 $pc=00001ad4 > > > > PC=1ada CCS=800 btaken=1 btarget=1ac6 > > cc_op=1 cc_src=3746 cc_dest=1 cc_result=ea2 cc_mask=0 > > $r0=00000000 $r1=00004360 $r2=00004308 $r3=0000026c > > $r4=00002076 $r5=00002022 $r6=00000000 $r7=00000000 > > $r8=00000000 $r9=00000ea2 $r10=00000002 $r11=00004308 > > $r12=00001080 $r13=00000ec0 $sp=0000bfd8 $pc=00001ad4 > > > > With the patch, we get only one: > > > > PC=1ad8 CCS=0 btaken=1 btarget=1ac6 > > cc_op=1 cc_src=3746 cc_dest=1 cc_result=ea2 cc_mask=0 > > $r0=00000000 $r1=00004360 $r2=00004308 $r3=0000026c > > $r4=00002076 $r5=00002022 $r6=00000000 $r7=00000000 > > $r8=00000000 $r9=00000ea2 $r10=00000002 $r11=00004308 > > $r12=00001080 $r13=00000ec0 $sp=0000bfd8 $pc=00001ad4 > > Hi, > > A concern I have is that we can't guard against all split prefix > sequences (e.g at page boundaries or with icount). So it may be more > confusing to see the prefix insns sometimes than every time.
I've forgotten most details, and have to refer to Rabin for useful answers. However, from the few glimpses I remember, basically I had to key on "singlestep" and force a re-translation to get usable dumps that didn't skip dump of state from all instructions inside a translated hunk on subsequent executions. There were some hacks^Wpatches left-out (for being too invasive and hackish, IIRC) to that effect, not sure how they affected this particular code here. > Perhaps we should more clearly be showing prefix state in the logs? No: I'd rather just not have prefix instructions dumped separately whenever possible as dumps get really big really quick, but maybe both this patch and a prefix indicator then, to reduce confusion. I guess a better deal would be a method that enables consistent dumps; page boundaries and icount shouldn't affect dumps. Maybe qemu has improved and there's a generic method to get useful register dumps *from every instruction at every execution* these days. > BTW, are you guys doing post-processing on this Certainly. The output was massaged to have the same format as dumps from another simulator, then fed into a script for use together with the executable to get readable output (somewhat at call-graph-level). > or is it only > for human inspection? > > Cheers, > Edgar > > > > > > Signed-off-by: Hans-Peter Nilsson <h...@axis.com> > > Signed-off-by: Rabin Vincent <rab...@axis.com> > > --- > > target-cris/translate.c | 3 ++- > > 1 file changed, 2 insertions(+), 1 deletion(-) > > > > diff --git a/target-cris/translate.c b/target-cris/translate.c > > index a4512b5..c9b1e65 100644 > > --- a/target-cris/translate.c > > +++ b/target-cris/translate.c > > @@ -3262,7 +3262,8 @@ void gen_intermediate_code(CPUCRISState *env, struct > > TranslationBlock *tb) > > } > > } while (!dc->is_jmp && !dc->cpustate_changed > > && !tcg_op_buf_full() > > - && !singlestep > > + /* We don't count prefix insns as separate wrt. singlestep. */ > > + && (!singlestep || (dc->tb_flags & PFIX_FLAG)) > > && (dc->pc < next_page_start) > > && num_insns < max_insns); > > > > -- > > 2.1.4 > > > brgds, H-P
