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	tests/perf: Test lseek influence on qcow2 block-status	2019-06-04 15:20:41 +02:00
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	tests: Move qdict-test-data.txt to tests/data/qobject/	2019-03-07 22:05:54 +01:00
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	Supply missing header guards	2019-06-12 13:20:21 +02:00
crypto-tls-x509-helpers.c
crypto-tls-x509-helpers.h	Supply missing header guards	2019-06-12 13:20:21 +02:00
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	Normalize position of header guard	2019-06-12 13:20:20 +02:00
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	tests: Do not use "\n" in g_test_message() strings	2019-03-07 22:16:22 +01:00
test-aio.c	util/async: make bh_aio_poll() O(1)	2020-02-22 08:26:47 +00:00
test-authz-list.c	Include qemu/module.h where needed, drop it from qemu-common.h	2019-06-12 13:18:33 +02:00
test-authz-listfile.c	Include qemu/module.h where needed, drop it from qemu-common.h	2019-06-12 13:18:33 +02:00
test-authz-pam.c	Include qemu/module.h where needed, drop it from qemu-common.h	2019-06-12 13:18:33 +02:00
test-authz-simple.c	Include qemu/module.h where needed, drop it from qemu-common.h	2019-06-12 13:18:33 +02:00
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	tests: Do not use "\n" in g_test_message() strings	2019-03-07 22:16:22 +01:00
test-crypto-afsplit.c
test-crypto-block.c	Include qemu/module.h where needed, drop it from qemu-common.h	2019-06-12 13:18:33 +02:00
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	Include qemu/module.h where needed, drop it from qemu-common.h	2019-06-12 13:18:33 +02:00
test-io-channel-command.c	Include qemu/module.h where needed, drop it from qemu-common.h	2019-06-12 13:18:33 +02:00
test-io-channel-file.c	Include qemu/module.h where needed, drop it from qemu-common.h	2019-06-12 13:18:33 +02:00
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	tests: test-qgraph: fix a memory leak	2019-03-11 16:33:49 +01:00
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-thread-pool: be more reliable	2019-06-03 14:03:00 +02:00
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