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43025f01a0
The riscv port does deletion and symbol table update for each relocation
while relaxing, so we are moving section bytes and scanning symbol table once
for each relocation. Compared to microblaze port, they record the relaxation
changes into a table, then do the deletion and symbol table update once per
section, rather than per relocation. Therefore, they should have better link
time complexity than us.
To improve the link time complexity, this patch try to make the deletion in
linear time. Compared to record the relaxation changes into a table, we
replace the unused relocation with R_RISCV_DELETE for the deleted bytes, and
then resolve them at the end of the section. Assuming the number of
R_RISCV_DELETE is m, and the number of symbols is n, the total link complexity
should be O(m) for moving section bytes, and O(m*n^2) for symbol table update.
If we record the relaxation changes into the table, and then sort the symbol
table by values, then probably can reduce the time complexity to O(m*n*log(n))
for updating symbol table, but it doesn't seem worth it for now.
bfd/
* elfnn-riscv.c (_riscv_relax_delete_bytes): Renamed from
riscv_relax_delete_bytes, updated to reduce the tiem complexity to O(m)
for memmove.
(typedef relax_delete_t): Function pointer declaration of delete functions.
(riscv_relax_delete_bytes): Can choose to use _riscv_relax_delete_piecewise
or _riscv_relax_delete_immediate for deletion.
(_riscv_relax_delete_piecewise): Just mark the deleted bytes as R_RISCV_DELETE.
(_riscv_relax_delete_immediate): Delete some bytes from a section while
relaxing.
(riscv_relax_resolve_delete_relocs): Delete the bytes for R_RISCV_DELETE
relocations from a section, at the end of _bfd_riscv_relax_section.
(_bfd_riscv_relax_call): Mark deleted bytes as R_RISCV_DELETE by reusing
R_RISCV_RELAX.
(_bfd_riscv_relax_lui): Likewise, but reuse R_RISCV_HI20 for lui, and reuse
R_RISCV_RELAX for c.lui.
(_bfd_riscv_relax_tls_le): Likewise, but resue R_RISCV_TPREL_HI20 and
R_RISCV_TPREL_ADD.
(_bfd_riscv_relax_pc): Likewise, but resue R_RISCV_PCREL_HI20 for auipc.
(_bfd_riscv_relax_align): Updated, don't need to resue relocation since
calling _riscv_relax_delete_immediate.
(_bfd_riscv_relax_delete): Removed.
(_bfd_riscv_relax_section): Set riscv_relax_delete_bytes for each relax_func,
to delete bytes immediately or later. Call riscv_relax_resolve_delete_relocs
to delete bytes for DELETE relocations from a section.
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| bfd | ||
| binutils | ||
| config | ||
| contrib | ||
| cpu | ||
| elfcpp | ||
| etc | ||
| gas | ||
| gdb | ||
| gdbserver | ||
| gdbsupport | ||
| gnulib | ||
| gold | ||
| gprof | ||
| gprofng | ||
| include | ||
| intl | ||
| ld | ||
| libbacktrace | ||
| libctf | ||
| libdecnumber | ||
| libiberty | ||
| opcodes | ||
| readline | ||
| sim | ||
| texinfo | ||
| zlib | ||
| .cvsignore | ||
| .editorconfig | ||
| .gitattributes | ||
| .gitignore | ||
| ar-lib | ||
| ChangeLog | ||
| compile | ||
| config-ml.in | ||
| config.guess | ||
| config.rpath | ||
| config.sub | ||
| configure | ||
| configure.ac | ||
| COPYING | ||
| COPYING3 | ||
| COPYING3.LIB | ||
| COPYING.LIB | ||
| COPYING.LIBGLOSS | ||
| COPYING.NEWLIB | ||
| depcomp | ||
| djunpack.bat | ||
| install-sh | ||
| libtool.m4 | ||
| lt~obsolete.m4 | ||
| ltgcc.m4 | ||
| ltmain.sh | ||
| ltoptions.m4 | ||
| ltsugar.m4 | ||
| ltversion.m4 | ||
| MAINTAINERS | ||
| Makefile.def | ||
| Makefile.in | ||
| Makefile.tpl | ||
| makefile.vms | ||
| missing | ||
| mkdep | ||
| mkinstalldirs | ||
| move-if-change | ||
| multilib.am | ||
| README | ||
| README-maintainer-mode | ||
| setup.com | ||
| src-release.sh | ||
| symlink-tree | ||
| test-driver | ||
| ylwrap | ||
README for GNU development tools This directory contains various GNU compilers, assemblers, linkers, debuggers, etc., plus their support routines, definitions, and documentation. If you are receiving this as part of a GDB release, see the file gdb/README. If with a binutils release, see binutils/README; if with a libg++ release, see libg++/README, etc. That'll give you info about this package -- supported targets, how to use it, how to report bugs, etc. It is now possible to automatically configure and build a variety of tools with one command. To build all of the tools contained herein, run the ``configure'' script here, e.g.: ./configure make To install them (by default in /usr/local/bin, /usr/local/lib, etc), then do: make install (If the configure script can't determine your type of computer, give it the name as an argument, for instance ``./configure sun4''. You can use the script ``config.sub'' to test whether a name is recognized; if it is, config.sub translates it to a triplet specifying CPU, vendor, and OS.) If you have more than one compiler on your system, it is often best to explicitly set CC in the environment before running configure, and to also set CC when running make. For example (assuming sh/bash/ksh): CC=gcc ./configure make A similar example using csh: setenv CC gcc ./configure make Much of the code and documentation enclosed is copyright by the Free Software Foundation, Inc. See the file COPYING or COPYING.LIB in the various directories, for a description of the GNU General Public License terms under which you can copy the files. REPORTING BUGS: Again, see gdb/README, binutils/README, etc., for info on where and how to report problems.