qemu/tests
Joseph Myers eca30647fc target/i386: reimplement f2xm1 using floatx80 operations
The x87 f2xm1 emulation is currently based around conversion to
double.  This is inherently unsuitable for a good emulation of any
floatx80 operation, even before considering that it is a particularly
naive implementation using double (computing with pow and then
subtracting 1 rather than attempting a better emulation using expm1).

Reimplement using the soft-float operations, including additions and
multiplications with higher precision where appropriate to limit
accumulation of errors.  I considered reusing some of the m68k code
for transcendental operations, but the instructions don't generally
correspond exactly to x87 operations (for example, m68k has 2^x and
e^x - 1, but not 2^x - 1); to avoid possible accumulation of errors
from applying multiple such operations each rounding to floatx80
precision, I wrote a direct implementation of 2^x - 1 instead.  It
would be possible in principle to make the implementation more
efficient by doing the intermediate operations directly with
significands, signs and exponents and not packing / unpacking floatx80
format for each operation, but that would make it significantly more
complicated and it's not clear that's worthwhile; the m68k emulation
doesn't try to do that.

A test is included with many randomly generated inputs.  The
assumption of the test is that the result in round-to-nearest mode
should always be one of the two closest floating-point numbers to the
mathematical value of 2^x - 1; the implementation aims to do somewhat
better than that (about 70 correct bits before rounding).  I haven't
investigated how accurate hardware is.

Signed-off-by: Joseph Myers <joseph@codesourcery.com>

Message-Id: <alpine.DEB.2.21.2006112341010.18393@digraph.polyomino.org.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-26 09:39:37 -04:00
..
acceptance Renesas hardware patches 2020-06-23 13:55:52 +01:00
data tests/acpi: update expected data files 2020-06-24 17:18:28 -04:00
decode decodetree: Drop check for less than 2 patterns in a group 2020-06-09 09:19:48 -07:00
docker tests/docker: Added docker build support for TSan. 2020-06-16 14:49:05 +01:00
fp softfloat: Change tininess_before_rounding to bool 2020-05-19 08:41:16 -07:00
guest-debug tests/guest-debug: catch hanging guests 2020-05-15 15:25:07 +01:00
image-fuzzer image-fuzzer: Use OSerror.strerror instead of tuple subscript 2019-11-05 16:36:11 +01:00
keys
migration tests/migration: fix unreachable path in stress test 2020-06-17 17:48:39 +01:00
multiboot tests/multiboot: Fix load address of test kernels 2019-07-30 12:25:43 +02:00
perf/block/qcow2
plugin configure: Add -Wno-psabi 2020-06-18 10:26:02 +01:00
qapi-schema qapi: New special feature flag "deprecated" 2020-03-17 21:42:47 +01:00
qemu-iotests qdev: Reject drive property override 2020-06-23 16:07:07 +02:00
qtest libqos: pci-pc: use 32-bit write for EJ register 2020-06-26 06:45:30 -04:00
rocker
tcg target/i386: reimplement f2xm1 using floatx80 operations 2020-06-26 09:39:37 -04:00
tsan tests/docker: Added docker build support for TSan. 2020-06-16 14:49:05 +01:00
uefi-test-tools edk2 build scripts: work around TianoCore#1607 without forcing Python 2 2019-10-07 15:14:15 +02:00
vm tests/vm: Remove flex/bison packages 2020-06-08 17:04:19 +01:00
vmstate-static-checker-data
.gitignore tests/tcg/aarch64: add a gdbstub testcase for SVE registers 2020-03-17 17:38:47 +00:00
atomic64-bench.c
atomic_add-bench.c
benchmark-crypto-cipher.c tests: benchmark crypto with fixed data size, not time period 2019-10-28 13:32:21 +01:00
benchmark-crypto-hash.c crypto: extend hash benchmark to cover more algorithms 2020-05-07 12:52:51 +01:00
benchmark-crypto-hmac.c
check-block-qdict.c
check-block.sh build: move TARGET_GPROF to config-host.mak 2020-02-12 16:29:27 +01:00
check-qdict.c
check-qjson.c test: Use g_strndup instead of plain strndup 2019-08-21 10:27:13 +02:00
check-qlist.c qobject: Eliminate qlist_iter(), use QLIST_FOREACH_ENTRY() instead 2020-04-30 06:51:15 +02:00
check-qlit.c
check-qnull.c
check-qnum.c
check-qobject.c
check-qom-interface.c
check-qom-proplist.c qom: Drop @errp parameter of object_property_del() 2020-05-15 07:08:14 +02:00
check-qstring.c
crypto-tls-psk-helpers.c
crypto-tls-psk-helpers.h
crypto-tls-x509-helpers.c
crypto-tls-x509-helpers.h
dbus-vmstate-daemon.sh tests: add dbus-vmstate-test 2020-01-06 18:41:32 +04:00
io-channel-helpers.c
io-channel-helpers.h
iothread.c tests/iothread: Always connect iothread GSource to a GMainContext 2020-01-07 14:32:57 +00:00
iothread.h
Makefile.include tests: Disable select tests under TSan, which hit TSan issue. 2020-06-16 14:49:05 +01:00
pkix_asn1_tab.c
ptimer-test-stubs.c util/qemu-timer: refactor deadline calculation for external timers 2019-08-20 17:26:21 +02:00
ptimer-test.c tests/ptimer: Remove unnecessary inclusion of libqtest.h 2020-01-12 11:42:40 +01:00
ptimer-test.h
qht-bench.c qht: Fix threshold rate calculation 2020-06-19 18:29:11 +01:00
rcutorture.c tests/rcutorture: mild documenting refactor of update thread 2020-02-25 17:42:59 +00:00
requirements.txt Acceptance test: add "boot_linux" tests 2020-03-17 18:55:52 -04:00
socket-helpers.c tests: specify the address family when checking bind 2019-08-22 17:30:25 +04:00
socket-helpers.h tests: specify the address family when checking bind 2019-08-22 17:30:25 +04:00
test-aio-multithread.c
test-aio.c util/async: make bh_aio_poll() O(1) 2020-02-22 08:26:47 +00:00
test-authz-list.c
test-authz-listfile.c
test-authz-pam.c
test-authz-simple.c
test-base64.c
test-bdrv-drain.c block: Drop @child_class from bdrv_child_perm() 2020-05-18 19:05:25 +02:00
test-bdrv-graph-mod.c block: Drop @child_class from bdrv_child_perm() 2020-05-18 19:05:25 +02:00
test-bitcnt.c
test-bitmap.c tests: use g_test_rand_int 2019-12-17 09:05:23 +01:00
test-bitops.c
test-block-backend.c Include qemu/main-loop.h less 2019-08-16 13:31:52 +02:00
test-block-iothread.c block: Use bdrv_default_perms() 2020-05-18 19:05:25 +02:00
test-blockjob-txn.c job: drop job_drain 2019-09-10 08:58:43 +02:00
test-blockjob.c job: take each job's lock individually in job_txn_apply 2020-04-07 14:34:47 +02:00
test-bufferiszero.c
test-char.c chardev: Use QEMUChrEvent enum in IOEventHandler typedef 2020-01-08 11:15:35 +01:00
test-clone-visitor.c
test-coroutine.c
test-crypto-afsplit.c
test-crypto-block.c
test-crypto-cipher.c
test-crypto-hash.c
test-crypto-hmac.c
test-crypto-ivgen.c
test-crypto-pbkdf.c
test-crypto-secret.c test-crypto-secret: add 'secret_keyring' object tests. 2020-06-15 11:33:51 +01:00
test-crypto-tlscredsx509.c glib: use portable g_setenv() 2019-12-17 09:05:23 +01:00
test-crypto-tlssession.c glib: use portable g_setenv() 2019-12-17 09:05:23 +01:00
test-crypto-xts.c
test-cutils.c
test-hbitmap.c block/dirty-bitmap: improve _next_dirty_area API 2020-03-18 14:03:46 -04:00
test-image-locking.c Include qemu/main-loop.h less 2019-08-16 13:31:52 +02:00
test-int128.c
test-io-channel-buffer.c
test-io-channel-command.c
test-io-channel-file.c
test-io-channel-socket.c socket: Add num connections to qio_channel_socket_async() 2019-09-03 23:24:42 +02:00
test-io-channel-tls.c glib: use portable g_setenv() 2019-12-17 09:05:23 +01:00
test-io-task.c io/task: Move 'qom/object.h' header to source 2020-06-10 12:09:37 -04:00
test-iov.c
test-keyval.c test-keyval: Tighten test of trailing crap after size 2019-12-18 12:28:44 +01:00
test-logging.c tests/test-logging: Fix test for -dfilter 0..0xffffffffffffffff 2020-04-29 08:01:52 +02:00
test-mul64.c
test-opts-visitor.c
test-qapi-util.c
test-qdev-global-props.c qdev: Convert bus-less devices to qdev_realize() with Coccinelle 2020-06-15 22:06:04 +02:00
test-qdist.c
test-qemu-opts.c test-qemu-opts: Simplify test_has_help_option() after bug fix 2020-04-29 08:01:51 +02:00
test-qga.c tests: use g_test_rand_int 2019-12-17 09:05:23 +01:00
test-qgraph.c
test-qht-par.c
test-qht.c
test-qmp-cmds.c qapi: Add feature flags to remaining definitions 2020-03-17 19:58:34 +01:00
test-qmp-event.c tests/test-qmp-event: Check event is actually emitted 2020-03-17 19:58:34 +01:00
test-qobject-input-visitor.c
test-qobject-output-visitor.c qapi: Assert output visitors see only valid enum values 2020-04-30 07:26:09 +02:00
test-rcu-list.c tests: Fix a bug with count variables 2020-03-06 10:35:15 +00:00
test-rcu-simpleq.c
test-rcu-slist.c rcu_queue: add QSLIST functions 2020-02-22 08:26:47 +00:00
test-rcu-tailq.c
test-replication.c tests/test-replication.c: Add test for for secondary node continuing replication 2020-03-03 18:04:47 +08:00
test-shift128.c
test-string-input-visitor.c tests: Fix uninitialized byte in test_visitor_in_fuzz 2019-08-20 17:26:19 +02:00
test-string-output-visitor.c qapi: Assert output visitors see only valid enum values 2020-04-30 07:26:09 +02:00
test-thread-pool.c
test-throttle.c test-throttle: Fix uninitialized use of burst_length 2019-08-20 17:26:19 +02:00
test-timed-average.c
test-util-filemonitor.c tests/test-util-filemonitor: Skip test on non-x86 Travis containers 2019-12-18 20:17:45 +00:00
test-util-sockets.c tests/util-sockets: add abstract unix socket cases 2020-05-20 10:34:45 +01:00
test-uuid.c
test-visitor-serialization.c
test-vmstate.c test-vmstate: Fix memleaks in test_load_qlist 2020-02-28 09:25:49 +01:00
test-write-threshold.c
test-x86-cpuid.c hw/i386: Update structures to save the number of nodes per package 2020-03-17 19:48:10 -04:00
test-xbzrle.c
vhost-user-bridge.c core: replace getpagesize() with qemu_real_host_page_size 2019-10-26 15:38:06 +02:00