On Mon, Oct 21, 2019 at 10:04 AM Kugan Vivekanandarajah <kugan.vivekanandara...@linaro.org> wrote: > > Hi Richard, > > Thanks for the pointers. > > > > On Fri, 11 Oct 2019 at 22:33, Richard Biener <richard.guent...@gmail.com> > wrote: > > > > On Fri, Oct 11, 2019 at 6:15 AM Kugan Vivekanandarajah > > <kugan.vivekanandara...@linaro.org> wrote: > > > > > > Hi Richard, > > > Thanks for the review. > > > > > > On Wed, 2 Oct 2019 at 20:41, Richard Biener <richard.guent...@gmail.com> > > > wrote: > > > > > > > > On Wed, Oct 2, 2019 at 10:39 AM Kugan Vivekanandarajah > > > > <kugan.vivekanandara...@linaro.org> wrote: > > > > > > > > > > Hi, > > > > > > > > > > As mentioned in the PR, attached patch adds COLLECT_AS_OPTIONS for > > > > > passing assembler options specified with -Wa, to the link-time driver. > > > > > > > > > > The proposed solution only works for uniform -Wa options across all > > > > > TUs. As mentioned by Richard Biener, supporting non-uniform -Wa flags > > > > > would require either adjusting partitioning according to flags or > > > > > emitting multiple object files from a single LTRANS CU. We could > > > > > consider this as a follow up. > > > > > > > > > > Bootstrapped and regression tests on arm-linux-gcc. Is this OK for > > > > > trunk? > > > > > > > > While it works for your simple cases it is unlikely to work in practice > > > > since > > > > your implementation needs the assembler options be present at the link > > > > command line. I agree that this might be the way for people to go when > > > > they face the issue but then it needs to be documented somewhere > > > > in the manual. > > > > > > > > That is, with COLLECT_AS_OPTION (why singular? I'd expected > > > > COLLECT_AS_OPTIONS) available to cc1 we could stream this string > > > > to lto_options and re-materialize it at link time (and diagnose > > > > mismatches > > > > even if we like). > > > OK. I will try to implement this. So the idea is if we provide > > > -Wa,options as part of the lto compile, this should be available > > > during link time. Like in: > > > > > > arm-linux-gnueabihf-gcc -march=armv7-a -mthumb -O2 -flto > > > -Wa,-mimplicit-it=always,-mthumb -c test.c > > > arm-linux-gnueabihf-gcc -flto test.o > > > > > > I am not sure where should we stream this. Currently, cl_optimization > > > has all the optimization flag provided for compiler and it is > > > autogenerated and all the flags are integer values. Do you have any > > > preference or example where this should be done. > > > > In lto_write_options, I'd simply append the contents of COLLECT_AS_OPTIONS > > (with -Wa, prepended to each of them), then recover them in lto-wrapper > > for each TU and pass them down to the LTRANS compiles (if they agree > > for all TUs, otherwise I'd warn and drop them). > > Attached patch streams it and also make sure that the options are the > same for all the TUs. Maybe it is a bit restrictive. > > What is the best place to document COLLECT_AS_OPTIONS. We don't seem > to document COLLECT_GCC_OPTIONS anywhere ?
Nowhere, it's an implementation detail then. > Attached patch passes regression and also fixes the original ARM > kernel build issue with tumb2. Did you try this with multiple assembler options? I see you stream them as -Wa,-mfpu=xyz,-mthumb but then compare the whole option strings so a mismatch with -Wa,-mthumb,-mfpu=xyz would be diagnosed. If there's a spec induced -Wa option do we get to see that as well? I can imagine -march=xyz enabling a -Wa option for example. + *collect_as = XNEWVEC (char, strlen (args_text) + 1); + strcpy (*collect_as, args_text); there's strdup. Btw, I'm not sure why you don't simply leave the -Wa option in the merged options [individually] and match them up but go the route of comparing strings and carrying that along separately. I think that would be much better. Thanks and sorry for the delay. Richard. > Thanks, > Kugan > > > > Richard. > > > > > Thanks, > > > Kugan > > > > > > > > > > > > > > > > > Richard. > > > > > > > > > Thanks, > > > > > Kugan > > > > > > > > > > > > > > > gcc/ChangeLog: > > > > > > > > > > 2019-10-02 kugan.vivekanandarajah > > > > > <kugan.vivekanandara...@linaro.org> > > > > > > > > > > PR lto/78353 > > > > > * gcc.c (putenv_COLLECT_AS_OPTION): New to set COLLECT_AS_OPTION in > > > > > env. > > > > > (driver::main): Call putenv_COLLECT_AS_OPTION. > > > > > * lto-wrapper.c (run_gcc): use COLLECT_AS_OPTION from env. > > > > > > > > > > gcc/testsuite/ChangeLog: > > > > > > > > > > 2019-10-02 kugan.vivekanandarajah > > > > > <kugan.vivekanandara...@linaro.org> > > > > > > > > > > PR lto/78353 > > > > > * gcc.target/arm/pr78353-1.c: New test. > > > > > * gcc.target/arm/pr78353-2.c: New test.
