Sync VEX/LICENSE.GPL with top-level COPYING file. We used 3 different
addresses for writing to the FSF to receive a copy of the GPL. Replace
all different variants with an URL <http://www.gnu.org/licenses/>.
The following files might still have some slightly different (L)GPL
copyright notice because they were derived from other programs:
- files under coregrind/m_demangle which come from libiberty:
cplus-dem.c, d-demangle.c, demangle.h, rust-demangle.c,
safe-ctype.c and safe-ctype.h
- coregrind/m_demangle/dyn-string.[hc] derived from GCC.
- coregrind/m_demangle/ansidecl.h derived from glibc.
- VEX files for FMA detived from glibc:
host_generic_maddf.h and host_generic_maddf.c
- files under coregrin/m_debuginfo derived from LZO:
lzoconf.h, lzodefs.h, minilzo-inl.c and minilzo.h
- files under coregrind/m_gdbserver detived from GDB:
gdb/signals.h, inferiors.c, regcache.c, regcache.h,
regdef.h, remote-utils.c, server.c, server.h, signals.c,
target.c, target.h and utils.c
Plus the following test files:
- none/tests/ppc32/testVMX.c derived from testVMX.
- ppc tests derived from QEMU: jm-insns.c, ppc64_helpers.h
and test_isa_3_0.c
- tests derived from bzip2 (with embedded GPL text in code):
hackedbz2.c, origin5-bz2.c, varinfo6.c
- tests detived from glibc: str_tester.c, pth_atfork1.c
- test detived from GCC libgomp: tc17_sembar.c
- performance tests derived from bzip2 or tinycc (with embedded GPL
text in code): bz2.c, test_input_for_tinycc.c and tinycc.c
Reg<->Reg MOV coalescing status is now a part of the HRegUsage.
This allows register allocation to query it two times without incurring
a performance penalty. This in turn allows to better keep track of
vreg<->vreg MOV coalescing so that all vregs in the coalesce chain
get the effective |dead_before| of the last vreg.
A small performance improvement has been observed because this allows
to coalesce even spilled vregs (previously only assigned ones).
Keeps track whether the bound real register has been reloaded from a virtual
register recently and if this real reg is still equal to that spill slot.
Avoids unnecessary spilling that vreg later, when this rreg needs
to be reserved, usually as a caller save register for a helper call.
Fixes BZ#384526.
Implements a new version of VEX register allocator which
keeps the main state per virtual registers, as opposed
to real registers in v2. This results in a simpler and
cleaner design and much simpler implementation.
It has been observed that the new allocator executes 20-30%
faster than the previous one but could produce slightly worse
spilling decisions. Overall performance improvement when running
the Valgrind performance regression test suite has been observed
in terms of a few percent.
The new register allocator (v3) is now the default one.
The old register allocator (v2) is still kept around and can be
activated with command line option '--vex-regalloc-version=2'.
Fixes BZ#381553.
