96e9ba5fbb
Correct a problem with the ISA bit being stripped from the addend of compressed branch relocations, affecting RELA targets. It has been there since microMIPS support has been added, with: commit df58fc944dbc6d5efd8d3826241b64b6af22f447 Author: Richard Sandiford <rdsandiford@googlemail.com> Date: Sun Jul 24 14:20:15 2011 +0000 <https://sourceware.org/ml/binutils/2011-07/msg00198.html>, ("MIPS: microMIPS ASE support") and R_MICROMIPS_PC7_S1, R_MICROMIPS_PC10_S1 and R_MICROMIPS_PC16_S1 relocations originally affected, and the R_MIPS16_PC16_S1 relocation recently added with commit c9775dde3277 ("MIPS16: Add R_MIPS16_PC16_S1 branch relocation support") actually triggering a linker error, due to its heightened processing strictness level: $ cat test.s .text .set mips16 foo: b bar .set bar, 0x1235 .align 4, 0 $ as -EB -n32 -o test.o test.s $ objdump -dr test.o test.o: file format elf32-ntradbigmips Disassembly of section .text: 00000000 <foo>: 0: f000 1000 b 4 <foo+0x4> 0: R_MIPS16_PC16_S1 *ABS*+0x1230 ... $ ld -melf32btsmipn32 -Ttext 0 -e 0 -o test test.o test.o: In function `foo': (.text+0x0): Branch to a non-instruction-aligned address $ This is because the ISA bit of the branch target does not match the ISA bit of the referring branch, hardwired to 1 of course. Retain the ISA bit then, so that the linker knows this is really MIPS16 code referred: $ objdump -dr fixed.o fixed.o: file format elf32-ntradbigmips Disassembly of section .text: 00000000 <foo>: 0: f000 1000 b 4 <foo+0x4> 0: R_MIPS16_PC16_S1 *ABS*+0x1231 ... $ ld -melf32btsmipn32 -Ttext 0 -e 0 -o fixed fixed.o $ Add a set of MIPS16 tests to cover the relevant cases, excluding linker tests though which would overflow the in-place addend on REL targets and use them as dump patterns for RELA targets only. gas/ * config/tc-mips.c (md_apply_fix) <BFD_RELOC_MIPS16_16_PCREL_S1> <BFD_RELOC_MICROMIPS_7_PCREL_S1, BFD_RELOC_MICROMIPS_10_PCREL_S1> <BFD_RELOC_MICROMIPS_16_PCREL_S1>: Keep the ISA bit in the addend calculated. * testsuite/gas/mips/mips16-branch-absolute.s: Set the ISA bit in `bar', export `foo'. * testsuite/gas/mips/mips16-branch-absolute.d: Adjust accordingly. * testsuite/gas/mips/mips16-branch-absolute-n32.d: Likewise. * testsuite/gas/mips/mips16-branch-absolute-n64.d: Likewise. * testsuite/gas/mips/mips16-branch-absolute-addend-n32.d: Likewise. * testsuite/gas/mips/mips16-branch-absolute-addend-n64.d: Likewise. ld/ * testsuite/ld-mips-elf/mips16-branch-absolute.d: New test. * testsuite/ld-mips-elf/mips16-branch-absolute-n32.d: New test. * testsuite/ld-mips-elf/mips16-branch-absolute-n64.d: New test. * testsuite/ld-mips-elf/mips16-branch-absolute-addend.d: New test. * testsuite/ld-mips-elf/mips16-branch-absolute-addend-n32.d: New test. * testsuite/ld-mips-elf/mips16-branch-absolute-addend-n64.d: New test. * testsuite/ld-mips-elf/mips-elf.exp: Run the new tests, except from `mips16-branch-absolute' and `mips16-branch-absolute-addend', referred indirectly only.
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.