Displaying 5 results from an estimated 5 matches for "pr8037".
2011 Jan 19
2
[LLVMdev] induction variable computation not preserving scev
...; Indvars isn't restructuring the loop there, so it ideally shouldn't
> need to call forgetLoop().
Hmm? It certainly is, it's changing the condition on the branch instruction
that makes up the loop latch!
Offhand, is it possible that the problem
> here is the same as the one in PR8037?
>
No, that only shows up when you try to run "opt -analyze -indvars
-scalar-evolution" by causing a crash. With that patch in place, you can see
that "opt -analyze -indvars -scalar-evolution" produces different values for
the SCEVs than you get with "opt -indvars | opt...
2011 Jan 19
0
[LLVMdev] induction variable computation not preserving scev
...ing SCEV properly. The attached patch shows the fix to this bug with a testcase, but it also causes five new test failures.
Indvars isn't restructuring the loop there, so it ideally shouldn't
need to call forgetLoop(). Offhand, is it possible that the problem
here is the same as the one in PR8037?
>
> Would someone be willing to take a look at the failures and figure out why we're getting worse output once this patch is applied? If I had to hazard a guess, I'd say that indvars is probably emitting code that can't be analyzed by SCEV as easily as the original.
It's c...
2011 Jan 18
2
[LLVMdev] induction variable computation not preserving scev
Hi,
I tracked down a bug in indvars where we weren't updating SCEV properly. The
attached patch shows the fix to this bug with a testcase, but it also causes
five new test failures.
Would someone be willing to take a look at the failures and figure out why
we're getting worse output once this patch is applied? If I had to hazard a
guess, I'd say that indvars is probably emitting code
2011 Jan 20
0
[LLVMdev] induction variable computation not preserving scev
...restructuring the loop there, so it ideally shouldn't
> need to call forgetLoop().
>
> Hmm? It certainly is, it's changing the condition on the branch instruction that makes up the loop latch!
>
> Offhand, is it possible that the problem
> here is the same as the one in PR8037?
>
> No, that only shows up when you try to run "opt -analyze -indvars -scalar-evolution" by causing a crash. With that patch in place, you can see that "opt -analyze -indvars -scalar-evolution" produces different values for the SCEVs than you get with "opt -indvars...
2011 Jan 20
1
[LLVMdev] induction variable computation not preserving scev
...it ideally shouldn't
> > need to call forgetLoop().
> >
> > Hmm? It certainly is, it's changing the condition on the branch
> instruction that makes up the loop latch!
> >
> > Offhand, is it possible that the problem
> > here is the same as the one in PR8037?
> >
> > No, that only shows up when you try to run "opt -analyze -indvars
> -scalar-evolution" by causing a crash. With that patch in place, you can see
> that "opt -analyze -indvars -scalar-evolution" produces different values for
> the SCEVs than you get...