Binutils with MCST patches
ed0816bd93
When linking the following code .global _prog_start _prog_start: mv x1, x1 mv x2, x2 .align 2 rvc_boundry: .option norvc .align 3 mv x3, x3 we currently emit an invalid two-byte 0 instruction. The actual output code looks like 0000000080000000 <_prog_start>: 80000000: 8086 mv ra,ra 80000002: 810a mv sp,sp 0000000080000004 <rvc_boundry>: 80000004: 0000 unimp 80000006: 0001 nop 80000008: 00018193 mv gp,gp This ends up manifesting due to the two-byte compressed NOP that's pessimisticly emitted by the ".align 2", which results in "rvc_boundry" being 2-byte aligned. frag_align_code() then goes and outputs a 2-byte NOP (which is invalid in no-RVC mode) to align the code back to a 4-byte boundry, which can't be relaxed away by the linker as it's not part of the R_RISCV_RELAX relocation. The fix is to just always emit the worst case possible alignment into the output as a single R_RISCV_RELAX, which the linker will then fix up. With this patch I get the expected code generation 0000000080000000 <_prog_start>: 80000000: 8086 mv ra,ra 80000002: 810a mv sp,sp 0000000080000004 <rvc_boundry>: 80000004: 00000013 nop 80000008: 00018193 mv gp,gp gas/ChangeLog 2017-09-07 Palmer Dabbelt <palmer@dabbelt.com> * config/tc-riscv.c (riscv_frag_align_code): Emit the entire alignment sequence inside R_RISCV_ALIGN. |
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bfd | ||
binutils | ||
config | ||
cpu | ||
elfcpp | ||
etc | ||
gas | ||
gdb | ||
gold | ||
gprof | ||
include | ||
intl | ||
ld | ||
libdecnumber | ||
libiberty | ||
opcodes | ||
readline | ||
sim | ||
texinfo | ||
zlib | ||
.cvsignore | ||
.gitattributes | ||
.gitignore | ||
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 | ||
README | ||
README-maintainer-mode | ||
setup.com | ||
src-release.sh | ||
symlink-tree | ||
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.