No description
3f7f365076
Fix a bug in `micromips_insn_at_pc_has_delay_slot' in instruction size determination via `mips_insn_size'. In the microMIPS case the latter function expects a lone 16-bit instruction word containing the major opcode regardless of whether the opcode requires another 16-bit word to follow, to form a complete 32-bit instruction. Code however passes the 16-bit word previously retrieved shifted left by 16 bits. Consequently `mips_insn_size', which examines the low 16-bit only, always sees 0. By pure coincidence a major opcode of 0 denotes a 32-bit instruction in the microMIPS instruction set, so the size of 4 is always returned here, and the following 16-bit word is then merged in the low 16 bits of the instruction previously shifted by 16 bits. The resulting 32-bit value is then passed to `micromips_instruction_has_delay_slot' for delay slot presence determination. This function in turn first examines the high 16 bits of the instruction word received and ignores the low 16 bits for 16-bit instructions. Consequently the only effect of this bug is an extraneous memory read issued to retrieve a subsequent 16-bit word where a 16-bit instruction is being examined. Which in turn may fail if the instruction is located right at the end of a readable memory area, in which case the lack of a delay slot will be reported to the caller, which may be incorrect. This code is used in breakpoint maintenance, for delay slot avoidance, so the bug would only trigger for the unlikely case of someone placing a breakpoint in a delay slot of an instruction which is at the end of readable memory. Which explains why the bug remained unnoticed so long. gdb/ * mips-tdep.c (micromips_insn_at_pc_has_delay_slot): Pass unshifted 16-bit microMIPS instruction word to `mips_insn_size'. |
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bfd | ||
binutils | ||
config | ||
cpu | ||
elfcpp | ||
etc | ||
gas | ||
gdb | ||
gold | ||
gprof | ||
include | ||
intl | ||
ld | ||
libdecnumber | ||
libiberty | ||
opcodes | ||
readline | ||
sim | ||
texinfo | ||
zlib | ||
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.gitattributes | ||
.gitignore | ||
ChangeLog | ||
compile | ||
config-ml.in | ||
config.guess | ||
config.rpath | ||
config.sub | ||
configure | ||
configure.ac | ||
COPYING | ||
COPYING.LIB | ||
COPYING.LIBGLOSS | ||
COPYING.NEWLIB | ||
COPYING3 | ||
COPYING3.LIB | ||
depcomp | ||
djunpack.bat | ||
install-sh | ||
libtool.m4 | ||
ltgcc.m4 | ||
ltmain.sh | ||
ltoptions.m4 | ||
ltsugar.m4 | ||
ltversion.m4 | ||
lt~obsolete.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.