Michael137 wrote: > > We didn't expect the debug info to increase that much based on the [#145967 > > (comment)](https://github.com/llvm/llvm-project/pull/145967#issuecomment-3099264478). > > Are they using some variant of -fno-sanitize-merge by any chance? > > Typically in optimized builds the trap instructions in each function get > > merged which results in the "trap reasons" in debug info being dropped and > > thus the "trap reasons" have a much smaller impact. > > Ah, the ~15% debug info overhead is for debug builds, which are unoptimized > (-O0). > > Most of the other build modes at Google that have optimizations enabled turn > off debug info. If I forcibly enable both optimizations and debug info, I do > get much lower overheads in the same ballpark as [#145967 > (comment)](https://github.com/llvm/llvm-project/pull/145967#issuecomment-3099264478)
Don't want to derail the review of this PR too much, but I am curious about the debug-info increase. A breakdown of section size increases would be interesting, if those are available. I don't have a good intuition for how many traps are emitted for real-world projects though, so if we emit a huge amount of them that would add up. I think the numbers we collected was for an unoptimized build (correct me if I'm wrong @delcypher). Also, aren't (at least some of) the trap instructions, disabled on unoptimized builds? But sounds like there's enough of them still emitted in unoptimized builds where it does get noticeable. https://github.com/llvm/llvm-project/pull/154618 _______________________________________________ lldb-commits mailing list lldb-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits
