search for: sizecl

...h ? Thanks, Nadav From: Sean Silva [mailto:silvas at purdue.edu] Sent: Monday, February 27, 2012 05:45 To: Hal Finkel Cc: Rotem, Nadav; llvmdev at cs.uiuc.edu Subject: Re: [LLVMdev] llvm-stress for fuzzing llvm I'm finding it useful to replace the main loop with:   for (unsigned i = 0, n = SizeCL/Modifiers.size(); i < n; ++i) {       Modifiers[i%Modifiers.size()]->Act();   } That way, changing the size by 1 adds exactly one instruction, which makes delta debugging MUCH easier. Maybe it would be worth changing? --Sean Silva  On Sun, Feb 26, 2012 at 9:23 PM, Sean Silva <silvas at...

I'm finding it useful to replace the main loop with: for (unsigned i = 0, n = SizeCL/Modifiers.size(); i < n; ++i) { Modifiers[i%Modifiers.size()]->Act(); } That way, changing the size by 1 adds exactly one instruction, which makes delta debugging MUCH easier. Maybe it would be worth changing? --Sean Silva On Sun, Feb 26, 2012 at 9:23 PM, Sean Silva <silvas at p...

...ilva [mailto:silvas at purdue.edu] > Sent: Monday, February 27, 2012 05:45 > To: Hal Finkel > Cc: Rotem, Nadav; llvmdev at cs.uiuc.edu > Subject: Re: [LLVMdev] llvm-stress for fuzzing llvm > > I'm finding it useful to replace the main loop with: > for (unsigned i = 0, n = SizeCL/Modifiers.size(); i < n; ++i) { > Modifiers[i%Modifiers.size()]->Act(); > } > > That way, changing the size by 1 adds exactly one instruction, which makes > delta debugging MUCH easier. Maybe it would be worth changing? > > --Sean Silva > > On Sun, Feb 26, 2...

Wow, nifty tool! I've already found a couple crashes! It is also really easy to pinpoint what is causing the error. Whenever you trigger a bug, run llvm-stress with the same seed but a really small size that doesn't trigger the bug (e.g. like 10). Then do binary search on the size. Eventually you find exactly the cutoff of size that triggers the bug (e.g. 539 runs fine, but 540 crashes),