similar to: Proposal for address-significance tables for --icf=safe

Hi Peter, This is a great proposal, thanks!. If you were worried about making the abi change have you thought about just going for an array of symbol names or hashes of symbol names where any matching symbol is considered address significant? This would sidestep the problem of keeping the symbol table indices in sync. It would be pessimistic for local symbols if the input SHT_ADDRSIG sections

On Tue, May 22, 2018 at 6:06 PM Peter Collingbourne via llvm-dev < llvm-dev at lists.llvm.org> wrote: > Hi all, > > Context: ld.gold has an --icf=safe flag which is intended to apply ICF > only to sections which can be safely merged according to the guarantees > provided by the language. It works using a set of heuristics (symbol name > matching and relocation scanning).

On Wed, May 23, 2018 at 3:25 AM, Peter Smith <peter.smith at linaro.org> wrote: > Hello, > > I think that the approach of using a section to record address > significance is a good one. I'm guessing it will have its own section > type and format? If it does would it make sense to try and submit this > to the GABI https://groups.google.com/forum/#!forum/generic-abi as

On Wed, May 23, 2018 at 12:16 PM, Peter Collingbourne <peter at pcc.me.uk> wrote: > On Wed, May 23, 2018 at 3:25 AM, Peter Smith <peter.smith at linaro.org> > wrote: > >> Hello, >> >> I think that the approach of using a section to record address >> significance is a good one. I'm guessing it will have its own section >> type and format? If

On Wed, May 23, 2018 at 3:07 PM, Peter Collingbourne <peter at pcc.me.uk> wrote: > > > On Wed, May 23, 2018 at 12:16 PM, Peter Collingbourne <peter at pcc.me.uk> > wrote: > >> On Wed, May 23, 2018 at 3:25 AM, Peter Smith <peter.smith at linaro.org> >> wrote: >> >>> Hello, >>> >>> I think that the approach of using a

Hi Peter, Thanks for doing this! On Wed, May 23, 2018 at 3:07 PM Peter Collingbourne via llvm-dev < llvm-dev at lists.llvm.org> wrote: > > > On Wed, May 23, 2018 at 12:16 PM, Peter Collingbourne <peter at pcc.me.uk> > wrote: > >> On Wed, May 23, 2018 at 3:25 AM, Peter Smith <peter.smith at linaro.org> >> wrote: >> >>> Hello,

Hello, I think that the approach of using a section to record address significance is a good one. I'm guessing it will have its own section type and format? If it does would it make sense to try and submit this to the GABI https://groups.google.com/forum/#!forum/generic-abi as it could be potentially useful for other linkers, for example gold? Happy to help out with reviews. Peter On 22

On Thu, May 31, 2018 at 5:06 PM Peter Collingbourne via llvm-dev < llvm-dev at lists.llvm.org> wrote: > On Wed, May 23, 2018 at 3:07 PM, Peter Collingbourne <peter at pcc.me.uk> > wrote: > >> >> >> On Wed, May 23, 2018 at 12:16 PM, Peter Collingbourne <peter at pcc.me.uk> >> wrote: >> >>> On Wed, May 23, 2018 at 3:25 AM, Peter

On Thu, May 31, 2018 at 5:13 PM, Eric Christopher <echristo at gmail.com> wrote: > > > On Thu, May 31, 2018 at 5:06 PM Peter Collingbourne via llvm-dev < > llvm-dev at lists.llvm.org> wrote: > >> On Wed, May 23, 2018 at 3:07 PM, Peter Collingbourne <peter at pcc.me.uk> >> wrote: >> >>> >>> >>> On Wed, May 23, 2018 at

On Thu, May 24, 2018 at 10:24 AM, Eric Christopher <echristo at gmail.com> wrote: > Hi Peter, > > Thanks for doing this! > > On Wed, May 23, 2018 at 3:07 PM Peter Collingbourne via llvm-dev < > llvm-dev at lists.llvm.org> wrote: > >> >> >> On Wed, May 23, 2018 at 12:16 PM, Peter Collingbourne <peter at pcc.me.uk> >> wrote: >>

On 23 May 2018 at 23:07, Peter Collingbourne <peter at pcc.me.uk> wrote: > > > On Wed, May 23, 2018 at 12:16 PM, Peter Collingbourne <peter at pcc.me.uk> > wrote: >> >> On Wed, May 23, 2018 at 3:25 AM, Peter Smith <peter.smith at linaro.org> >> wrote: >>> >>> Hello, >>> >>> I think that the approach of using a

Hi, Many linkers including lld have a feature to eliminate unused sections from output to make output smaller (which is essentially a mark-sweep gc where sections are vertices and relocations are edges). lld and GNU gold have yet another feature, ICF, to merge functions by contents to save more space. When we remove or merge a function, we want to eliminate its exception handling information as

No I haven't. Thank you for the pointer. Looks like the problem of the inverted edges was discussed there. But I guess my bigger question is this: why do we still create one big .eh_frame even if -ffunction-sections is given? When the option is given, Clang creates .text, .rela.text and .gcc_exception_table sections for each function, but it still creates a monolithic .eh_frame that covers

2018-02-08 9:33 GMT-08:00 Steven Wu <stevenwu at apple.com>: > > > On Feb 7, 2018, at 4:03 PM, Mehdi AMINI <joker.eph at gmail.com> wrote: > > > > 2018-02-07 12:45 GMT-08:00 Steven Wu <stevenwu at apple.com>: > >> >> >> On Feb 7, 2018, at 12:36 PM, Mehdi AMINI <joker.eph at gmail.com> wrote: >> >> > But it is

> On Feb 8, 2018, at 10:28 AM, Mehdi AMINI <joker.eph at gmail.com> wrote: > > > > 2018-02-08 9:33 GMT-08:00 Steven Wu <stevenwu at apple.com <mailto:stevenwu at apple.com>>: > > >> On Feb 7, 2018, at 4:03 PM, Mehdi AMINI <joker.eph at gmail.com <mailto:joker.eph at gmail.com>> wrote: >> >> >> >> 2018-02-07

2018-02-08 10:44 GMT-08:00 Steven Wu <stevenwu at apple.com>: > > > On Feb 8, 2018, at 10:28 AM, Mehdi AMINI <joker.eph at gmail.com> wrote: > > > > 2018-02-08 9:33 GMT-08:00 Steven Wu <stevenwu at apple.com>: > >> >> >> On Feb 7, 2018, at 4:03 PM, Mehdi AMINI <joker.eph at gmail.com> wrote: >> >> >> >>

2018-02-07 12:45 GMT-08:00 Steven Wu <stevenwu at apple.com>: > > > On Feb 7, 2018, at 12:36 PM, Mehdi AMINI <joker.eph at gmail.com> wrote: > > > But it is interesting in general because according to the definition > for local_unnamed_addr, the symbol has to be linkonce_odr to be auto hide > as well. ThinLTO promotion can break that as well. > > What do

SGTM. I would do as 2 separate patches, the local per-module case, then the case that requires linker/global analysis. Thanks, Teresa On Fri, Feb 9, 2018 at 9:20 AM, Steven Wu via llvm-dev < llvm-dev at lists.llvm.org> wrote: > Are we agreeing on this is what we should do? If so, I will prepare a > patch. > > Steven > > > On Feb 8, 2018, at 11:07 AM, Mehdi AMINI

> On Feb 7, 2018, at 4:03 PM, Mehdi AMINI <joker.eph at gmail.com> wrote: > > > > 2018-02-07 12:45 GMT-08:00 Steven Wu <stevenwu at apple.com <mailto:stevenwu at apple.com>>: > > >> On Feb 7, 2018, at 12:36 PM, Mehdi AMINI <joker.eph at gmail.com <mailto:joker.eph at gmail.com>> wrote: >> >> > But it is interesting in

Steven Wu <stevenwu at apple.com> writes: >> On Feb 15, 2018, at 4:16 PM, Rafael Avila de Espindola <rafael.espindola at gmail.com> wrote: >> >> Steven Wu <stevenwu at apple.com> writes: >> >>> I did a bit more digging for the auto hide problem. Here is my finding that prevent us from doing this by default in GlobalOpts >>>