Re: [RFC PATCH] Detecting lifetime-dse issues via Valgrind [PR66487]

2023-11-15 Thread Daniil Frolov
On 2023-11-13 02:53, Sam James wrote: Sam James writes: Alexander Monakov writes: [...] I'm very curious what you mean by "this has come up with LLVM [] too": ttbomk, LLVM doesn't do such lifetime-based optimization yet, which is why compiling LLVM with LLVM doesn't break it. Can you shar

Re: [RFC PATCH] Detecting lifetime-dse issues via Valgrind [PR66487]

2023-11-12 Thread Sam James
Sam James writes: > Alexander Monakov writes: > [...] >> >> I'm very curious what you mean by "this has come up with LLVM [] too": >> ttbomk, >> LLVM doesn't do such lifetime-based optimization yet, which is why compiling >> LLVM with LLVM doesn't break it. Can you share some examples? Or do

Re: [RFC PATCH] Detecting lifetime-dse issues via Valgrind [PR66487]

2023-11-12 Thread Sam James
Alexander Monakov writes: > On Sat, 11 Nov 2023, Sam James wrote: > >> > Valgrind client requests are offered as macros that emit inline asm. For >> > use >> > in code generation, we need to wrap it in a built-in. We know that >> > implementing >> > such a built-in in libgcc is undesirable,

Re: [RFC PATCH] Detecting lifetime-dse issues via Valgrind [PR66487]

2023-11-12 Thread Alexander Monakov
On Sat, 11 Nov 2023, Sam James wrote: > > Valgrind client requests are offered as macros that emit inline asm. For > > use > > in code generation, we need to wrap it in a built-in. We know that > > implementing > > such a built-in in libgcc is undesirable, [...]. > > Perhaps less objectiona

Re: [RFC PATCH] Detecting lifetime-dse issues via Valgrind [PR66487]

2023-11-11 Thread Sam James
exactl...@ispras.ru writes: > From: Daniil Frolov > > PR 66487 is asking to provide sanitizer-like detection for C++ object lifetime > violations that are worked around with -fno-lifetime-dse in Firefox, LLVM, > OpenJade. > > The discussion in the PR was centered around extending MSan, but MSan