search for: getfoldedspillsize

...r the faint of heart :) This is from a large and messy C file (Perlbench's regexec.c), reduced by bugpoint down to 1050 lines of IR. Perhaps I can paste it on pastebin. Just for fun, I added some debug dumps for machine instructions that spill registers (i.e. return non-zero from MachineInstr::getFoldedSpillSize()) that are fed by load-immediates and kill that register. Then I bootstrapped LLVM/Clang/compiler-rt with those dumps. Turns out there are 5692 occurrences of that. I might have more luck reducing one of those files. On Wed, Feb 20, 2019 at 7:16 PM Quentin Colombet <qcolombet at apple.com>...

...heart :) > This is from a large and messy C file (Perlbench's regexec.c), reduced by bugpoint down to 1050 lines of IR. Perhaps I can paste it on pastebin. > > Just for fun, I added some debug dumps for machine instructions that spill registers (i.e. return non-zero from MachineInstr::getFoldedSpillSize()) that are fed by load-immediates and kill that register. Then I bootstrapped LLVM/Clang/compiler-rt with those dumps. Turns out there are 5692 occurrences of that. I might have more luck reducing one of those files. > > On Wed, Feb 20, 2019 at 7:16 PM Quentin Colombet <qcolombet at appl...

...and messy C file (Perlbench's regexec.c), reduced by >> bugpoint down to 1050 lines of IR. Perhaps I can paste it on pastebin. >> >> Just for fun, I added some debug dumps for machine instructions that >> spill registers (i.e. return non-zero from >> MachineInstr::getFoldedSpillSize()) that are fed by load-immediates and >> kill that register. Then I bootstrapped LLVM/Clang/compiler-rt with those >> dumps. Turns out there are 5692 occurrences of that. I might have more luck >> reducing one of those files. >> >> On Wed, Feb 20, 2019 at 7:16 PM Quen...

I have encountered a rather odd situation with Greedy where it will end up spilling a register that was populated with a zero (with a trivially rematerializable load-immediate instruction). In fact, it spills 3 such values (LICM moves stuff out of a loop, register coalescer replaces copies with load-immediates and then Greedy spills them). I personally can't think of a situation where a spill