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In the medany code model the compiler generates PCREL_HI20+PCREL_LO12 relocation pairs against local symbols because HI20+LO12 relocations can't reach high addresses. We relax HI20+LO12 pairs to GPREL relocations when possible, which is an important optimization for Dhrystone. Without this commit we are unable to relax PCREL_HI20+PCREL_LO12 pairs to GPREL when possible, causing a 10% permormance hit on Dhrystone on Rocket. Note that we'll now relax la gp, __global_pointer$ to mv gp, gp which probably isn't what you want in your entry code. Users who want gp-relative symbols to continue to resolve should add ".option norelax" accordingly. Due to this, the assembler now pairs PCREL relocations with RELAX relocations when they're expected to be relaxed just like every other relaxable relocation. bfd/ChangeLog 2017-10-19 Palmer Dabbelt <palmer@dabbelt.com> * elfnn-riscv.c (riscv_pcgp_hi_reloc): New structure. (riscv_pcgp_lo_reloc): Likewise. (riscv_pcgp_relocs): Likewise. (riscv_init_pcgp_relocs): New function. (riscv_free_pcgp_relocs): Likewise. (riscv_record_pcgp_hi_reloc): Likewise. (riscv_record_pcgp_lo_reloc): Likewise. (riscv_delete_pcgp_hi_reloc): Likewise. (riscv_use_pcgp_hi_reloc): Likewise. (riscv_record_pcgp_lo_reloc): Likewise. (riscv_find_pcgp_lo_reloc): Likewise. (riscv_delete_pcgp_lo_reloc): Likewise. (_bfd_riscv_relax_pc): Likewise. (_bfd_riscv_relax_section): Handle R_RISCV_PCREL_* relocations via the new functions above. gas/ChangeLog 2017-10-19 Palmer Dabbelt <palmer@dabbelt.com> * config/tc-riscv.c (md_apply_fix): Mark BFD_RELOC_RISCV_PCREL_HI20 as relaxable when relaxations are enabled.
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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.
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