In QEMU 8.0, we've been seeing deadlocks in bdrv_graph_wrlock(). They
come from callers that hold an AioContext lock, which is not allowed
during polling. In theory, we could temporarily release the lock, but
callers are inconsistent about whether they hold a lock, and if they do,
some are also confused about which one they hold. While all of this is
fixable, it's not trivial, and the best course of action for 8.0.1 is
probably just disabling the graph locking code temporarily.
We don't currently rely on graph locking yet. It is supposed to replace
the AioContext lock eventually to enable multiqueue support, but as long
as we still have the AioContext lock, it is sufficient without the graph
lock. Once the AioContext lock goes away, the deadlock doesn't exist any
more either and this commit can be reverted. (Of course, it can also be
reverted while the AioContext lock still exists if the callers have been
fixed.)
Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230517152834.277483-2-kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230502184134.534703-3-stefanha@redhat.com>
[kwolf: Restrict to CONFIG_POSIX, Windows doesn't support polling]
Tested-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
QEMU's event loop supports nesting, which means that event handler
functions may themselves call aio_poll(). The condition that triggered a
handler must be reset before the nested aio_poll() call, otherwise the
same handler will be called and immediately re-enter aio_poll. This
leads to an infinite loop and stack exhaustion.
Poll handlers are especially prone to this issue, because they typically
reset their condition by finishing the processing of pending work.
Unfortunately it is during the processing of pending work that nested
aio_poll() calls typically occur and the condition has not yet been
reset.
Disable a poll handler during ->io_poll_ready() so that a nested
aio_poll() call cannot invoke ->io_poll_ready() again. As a result, the
disabled poll handler and its associated fd handler do not run during
the nested aio_poll(). Calling aio_set_fd_handler() from inside nested
aio_poll() could cause it to run again. If the fd handler is pending
inside nested aio_poll(), then it will also run again.
In theory fd handlers can be affected by the same issue, but they are
more likely to reset the condition before calling nested aio_poll().
This is a special case and it's somewhat complex, but I don't see a way
around it as long as nested aio_poll() is supported.
Cc: qemu-stable@nongnu.org
Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=2186181
Fixes: c382706925 ("block: Mark bdrv_co_io_(un)plug() and callers GRAPH_RDLOCK")
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230502184134.534703-2-stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Skip TestBlockdevReopen.test_insert_compress_filter() if the 'compress'
driver isn't available.
In order to make the test succeed when the case is skipped, we also need
to remove any output from it (which would be missing in the case where
we skip it). This is done by replacing qemu_io_log() with qemu_io(). In
case of failure, qemu_io() raises an exception with the output of the
qemu-io binary in its message, so we don't actually lose anything.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230511143801.255021-1-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
There are some conditions under which we don't actually need to do
anything for taking a reader lock: Writing the graph is only possible
from the main context while holding the BQL. So if a reader is running
in the main context under the BQL and knows that it won't be interrupted
until the next writer runs, we don't actually need to do anything.
This is the case if the reader code neither has a nested event loop
(this is forbidden anyway while you hold the lock) nor is a coroutine
(because a writer could run when the coroutine has yielded).
These conditions are exactly what bdrv_graph_rdlock_main_loop() asserts.
They are not fulfilled in bdrv_graph_co_rdlock(), which always runs in a
coroutine.
This deletes the shortcuts in bdrv_graph_co_rdlock() that skip taking
the reader lock in the main thread.
Reported-by: Fiona Ebner <f.ebner@proxmox.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230510203601.418015-9-kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
When jobs are sleeping, for example to enforce a given rate limit, they
can be reentered early, in particular in order to get paused, to update
the rate limit or to get cancelled.
Before this patch, they behave in this case as if they had fully
completed their rate limiting delay. This means that requests are sped
up beyond their limit, violating the constraints that the user gave us.
Change the block jobs to sleep in a loop until the necessary delay is
completed, while still allowing cancelling them immediately as well
pausing (handled by the pause point in job_sleep_ns()) and updating the
rate limit.
This change is also motivated by iotests cases being prone to fail
because drain operations pause and unpause them so often that block jobs
complete earlier than they are supposed to. In particular, the next
commit would fail iotests 030 without this change.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230510203601.418015-8-kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
bdrv_unref() is a no_coroutine_fn, so calling it from coroutine context
is invalid. Use bdrv_co_unref() instead.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230510203601.418015-7-kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
If we take a reader lock, we can't call any functions that take a writer
lock internally without causing deadlocks once the reader lock is
actually enforced in the main thread, too. Take the reader lock only
where it is actually needed.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230510203601.418015-6-kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
If we take a reader lock, we can't call any functions that take a writer
lock internally without causing deadlocks once the reader lock is
actually enforced in the main thread, too. Take the reader lock only
where it is actually needed.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230510203601.418015-5-kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
qcow2_do_open() calls a few no_co_wrappers that wrap functions taking
the graph lock internally as a writer. Therefore, it can't hold the
reader lock across these calls, it causes deadlocks. Drop the lock
temporarily around the calls.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230510203601.418015-4-kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
There are some error paths in blk_exp_add() that jump to 'fail:' before
'exp' is even created. So we can't just unconditionally access exp->blk.
Add a NULL check, and switch from exp->blk to blk, which is available
earlier, just to be extra sure that we really cover all cases where
BlockDevOps could have been set for it (in practice, this only happens
in drv->create() today, so this part of the change isn't strictly
necessary).
Fixes: Coverity CID 1509238
Fixes: de79b52604
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230510203601.418015-3-kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Tested-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
These are functions that modify the graph, so they must be able to take
a writer lock. This is impossible if they already hold the reader lock.
If they need a reader lock for some of their operations, they should
take it internally.
Many of them go through blk_*(), which will always take the lock itself.
Direct calls of bdrv_*() need to take the reader lock. Note that while
locking for bdrv_co_*() calls is checked by TSA, this is not the case
for the mixed_coroutine_fns bdrv_*(). Holding the lock is still required
when they are called from coroutine context like here!
This effectively reverts 4ec8df0183, but adds some internal locking
instead.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230510203601.418015-2-kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
"zlib" clusters are actually raw deflate (RFC1951) clusters without
zlib headers.
Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>
Message-Id: <168424874322.11954.1340942046351859521-0@git.sr.ht>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Let's simplify things:
First, actions generally don't need access to common BlkActionState
structure. The only exclusion are backup actions that need
block_job_txn.
Next, for transaction actions of Transaction API is more native to
allocated state structure in the action itself.
So, do the following transformation:
1. Let all actions be represented by a function with corresponding
structure as arguments.
2. Instead of array-map marshaller, let's make a function, that calls
corresponding action directly.
3. BlkActionOps and BlkActionState structures become unused
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-Id: <20230510150624.310640-7-vsementsov@yandex-team.ru>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Other bitmap related actions use the .bitmap pointer in .abort action,
let's do same here:
1. It helps further refactoring, as bitmap-add is the only bitmap
action that uses state.action in .abort
2. It must be safe: transaction actions rely on the fact that on
.abort() the state is the same as at the end of .prepare(), so that
in .abort() we could precisely rollback the changes done by
.prepare().
The only way to remove the bitmap during transaction should be
block-dirty-bitmap-remove action, but it postpones actual removal to
.commit(), so we are OK on any rollback path. (Note also that
bitmap-remove is the only bitmap action that has .commit() phase,
except for simple g_free the state on .clean())
3. Again, other bitmap actions behave this way: keep the bitmap pointer
during the transaction.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-Id: <20230510150624.310640-6-vsementsov@yandex-team.ru>
[kwolf: Also remove the now unused BlockDirtyBitmapState.prepared]
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Only backup supports GROUPED mode. Make this logic more clear. And
avoid passing extra thing to each action.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-Id: <20230510150624.310640-5-vsementsov@yandex-team.ru>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230510150624.310640-4-vsementsov@yandex-team.ru>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Look at qmp_transaction(): dev_list is not obvious name for list of
actions. Let's look at qapi spec, this argument is "actions". Let's
follow the common practice of using same argument names in qapi scheme
and code.
To be honest, rename props to properties for same reason.
Next, we have to rename global map of actions, to not conflict with new
name for function argument.
Rename also dev_entry loop variable accordingly to new name of the
list.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230510150624.310640-3-vsementsov@yandex-team.ru>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are going to add more block-graph modifying transaction actions,
and block-graph modifying functions are already based on Transaction
API.
Next, we'll need to separately update permissions after several
graph-modifying actions, and this would be simple with help of
Transaction API.
So, now let's just transform what we have into new-style transaction
actions.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-Id: <20230510150624.310640-2-vsementsov@yandex-team.ru>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This reverts commit b320e21c48,
which accidentally broke TCG, because it made the TCG -cpu max
report the presence of MTE to the guest even if the board hadn't
enabled MTE by wiring up the tag RAM. This meant that if the guest
then tried to use MTE QEMU would segfault accessing the
non-existent tag RAM:
==346473==ERROR: UndefinedBehaviorSanitizer: SEGV on unknown address (pc 0x55f328952a4a bp 0x00000213a400 sp 0x7f7871859b80 T346476)
==346473==The signal is caused by a READ memory access.
==346473==Hint: this fault was caused by a dereference of a high value address (see register values below). Disassemble the provided pc to learn which register was used.
#0 0x55f328952a4a in address_space_to_flatview /mnt/nvmedisk/linaro/qemu-from-laptop/qemu/include/exec/memory.h:1108:12
#1 0x55f328952a4a in address_space_translate /mnt/nvmedisk/linaro/qemu-from-laptop/qemu/include/exec/memory.h:2797:31
#2 0x55f328952a4a in allocation_tag_mem /mnt/nvmedisk/linaro/qemu-from-laptop/qemu/build/arm-clang/../../target/arm/tcg/mte_helper.c:176:10
#3 0x55f32895366c in helper_stgm /mnt/nvmedisk/linaro/qemu-from-laptop/qemu/build/arm-clang/../../target/arm/tcg/mte_helper.c:461:15
#4 0x7f782431a293 (<unknown module>)
It's also not clear that the KVM logic is correct either:
MTE defaults to on there, rather than being only on if the
board wants it on.
Revert the whole commit for now so we can sort out the issues.
(We didn't catch this in CI because we have no test cases in
avocado that use guests with MTE support.)
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20230519145808.348701-1-peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
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Merge tag 'pull-hex-20230518-1' of https://github.com/quic/qemu into staging
Hexagon update
# -----BEGIN PGP SIGNATURE-----
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# gpg: Signature made Thu 18 May 2023 12:48:24 PM PDT
# gpg: using RSA key 3635C788CE62B91FD4C59AB47B0244FB12DE4422
# gpg: Good signature from "Taylor Simpson (Rock on) <tsimpson@quicinc.com>" [unknown]
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg: There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 3635 C788 CE62 B91F D4C5 9AB4 7B02 44FB 12DE 4422
* tag 'pull-hex-20230518-1' of https://github.com/quic/qemu: (44 commits)
Hexagon (linux-user/hexagon): handle breakpoints
Hexagon (gdbstub): add HVX support
Hexagon (gdbstub): fix p3:0 read and write via stub
Hexagon: add core gdbstub xml data for LLDB
gdbstub: add test for untimely stop-reply packets
gdbstub: only send stop-reply packets when allowed to
Remove test_vshuff from hvx_misc tests
Hexagon (decode): look for pkts with multiple insns at the same slot
Hexagon (iclass): update J4_hintjumpr slot constraints
Hexagon: append eflags to unknown cpu model string
Hexagon: list available CPUs with `-cpu help`
Hexagon (target/hexagon/*.py): raise exception on reg parsing error
target/hexagon: fix = vs. == mishap
Hexagon (target/hexagon) Additional instructions handled by idef-parser
Hexagon (target/hexagon) Move items to DisasContext
Hexagon (target/hexagon) Move pkt_has_store_s1 to DisasContext
Hexagon (target/hexagon) Move pred_written to DisasContext
Hexagon (target/hexagon) Move new_pred_value to DisasContext
Hexagon (target/hexagon) Move new_value to DisasContext
Hexagon (target/hexagon) Make special new_value for USR
...
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This enables LLDB to work with hexagon linux-user mode through the GDB
remote protocol.
Helped-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Matheus Tavares Bernardino <quic_mathbern@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <c287a129dcbe7d974d8b7608e8672d34a3c91c04.1683214375.git.quic_mathbern@quicinc.com>
In the previous commit, we modified gdbstub.c to only send stop-reply
packets as a response to GDB commands that accept it. Now, let's add a
test for this intended behavior. Running this test before the fix from
the previous commit fails as QEMU sends a stop-reply packet
asynchronously, when GDB was in fact waiting an ACK.
Signed-off-by: Matheus Tavares Bernardino <quic_mathbern@quicinc.com>
Acked-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <a30d93b9a8d66e9d9294354cfa2fc3af35f00202.1683214375.git.quic_mathbern@quicinc.com>
GDB's remote serial protocol allows stop-reply messages to be sent by
the stub either as a notification packet or as a reply to a GDB command
(provided that the cmd accepts such a response). QEMU currently does not
implement notification packets, so it should only send stop-replies
synchronously and when requested. Nevertheless, it still issues
unsolicited stop messages through gdb_vm_state_change().
Although this behavior doesn't seem to cause problems with GDB itself
(the messages are just ignored), it can impact other debuggers that
implement the GDB remote serial protocol, like hexagon-lldb. Let's
change the gdbstub to send stop messages only as a response to a
previous GDB command that accepts such a reply.
Signed-off-by: Matheus Tavares Bernardino <quic_mathbern@quicinc.com>
Acked-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <a49c0897fc22a6a7827c8dfc32aef2e1d933ec6b.1683214375.git.quic_mathbern@quicinc.com>
test_vshuff checks that the vshuff instruction works correctly when
both vector registers are the same. Using vshuff in this way is
undefined and will be rejected by the compiler in a future version of
the toolchain.
Signed-off-by: Marco Liebel <quic_mliebel@quicinc.com>
Reviewed-by: Brian Cain <bcain@quicinc.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Tested-by: Taylor Simpson <tsimpson@quicinc.com>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <20230509184231.2467626-1-quic_mliebel@quicinc.com>
Each slot in a packet can be assigned to at most one instruction.
Although the assembler generally ought to enforce this rule, we better
be safe than sorry and also do some check to properly throw an "invalid
packet" exception on wrong slot assignments.
This should also make it easier to debug possible future errors caused
by missing updates to `find_iclass_slots()` rules in
target/hexagon/iclass.c.
Co-authored-by: Taylor Simpson <tsimpson@quicinc.com>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Signed-off-by: Matheus Tavares Bernardino <quic_mathbern@quicinc.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Tested-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <f8b829443523568823d062adf8bf6659bc6d4a3f.1683552984.git.quic_mathbern@quicinc.com>
The Hexagon PRM says that "The assembler automatically encodes
instructions in the packet in the proper order. In the binary encoding
of a packet, the instructions must be ordered from Slot 3 down to
Slot 0."
Prior to the architecture version v73, the slot constraints from
instruction "hintjr" only allowed it to be executed at slot 2.
With that in mind, consider the packet:
{
hintjr(r0)
nop
nop
if (!p0) memd(r1+#0) = r1:0
}
To satisfy the ordering rule quoted from the PRM, the assembler would,
thus, move one of the nops to the first position, so that it can be
assigned to slot 3 and the subsequent hintjr to slot 2.
However, since v73, hintjr can be executed at either slot 2 or 3. So
there is no need to reorder that packet and the assembler will encode it
as is. When QEMU tries to execute it, however, we end up hitting a
"misaliged store" exception because both the store and the hintjr will
be assigned to store 0, and some functions like `slot_is_predicated()`
expect the decode machinery to assign only one instruction per slot. In
particular, the mentioned function will traverse the packet until it
finds the first instruction at the desired slot which, for slot 0, will
be hintjr. Since hintjr is not predicated, the result is that we try to
execute the store regardless of the predicate. And because the predicate
is false, we had not previously loaded hex_store_addr[0] or
hex_store_width[0]. As a result, the store will decide de width based on
trash memory, causing it to be misaligned.
Update the slot constraints for hintjr so that QEMU can properly handle
such encodings.
Note: to avoid similar-but-not-identical issues in the future, we should
look for multiple instructions at the same slot during decoding time and
throw an invalid packet exception. That will be done in the subsequent
commit.
Signed-off-by: Matheus Tavares Bernardino <quic_mathbern@quicinc.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <0fcd8293642c6324119fbbab44741164bcbd04fb.1673616964.git.quic_mathbern@quicinc.com>
Running qemu-hexagon with a binary that was compiled for an arch version
unknown by qemu can produce a somewhat confusing message:
qemu-hexagon: unable to find CPU model 'unknown'
Let's give a bit more info by appending the eflags so that the message
becomes:
qemu-hexagon: unable to find CPU model 'unknown (0x69)'
Signed-off-by: Matheus Tavares Bernardino <quic_mathbern@quicinc.com>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Tested-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <8a8d013cc619b94fd4fb577ae6a8df26cedb972b.1683225804.git.quic_mathbern@quicinc.com>
Currently, qemu-hexagon only models the v67 cpu. Nonetheless if we try
to get this information with `-cpu help`, qemu just exists with an error
code and no output. Let's correct that.
The code is basically a copy from target/alpha/cpu.h, but we strip the
"-hexagon-cpu" suffix before printing. This is to avoid confusing
situations like the following:
$ qemu-hexagon -cpu help
Available CPUs:
v67-hexagon-cpu
$ qemu-hexagon -cpu v67-hexagon-cpu ./prog
qemu-hexagon: unable to find CPU model 'v67-hexagon-cpu'
Signed-off-by: Matheus Tavares Bernardino <quic_mathbern@quicinc.com>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Tested-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <b946e17c7e17eed9095700b54c5ead36e5d55dfa.1683225804.git.quic_mathbern@quicinc.com>
Currently, the python scripts used for the hexagon building will not
abort the compilation when there is an error parsing a register. Let's
make the compilation properly fail in such cases by rasing an exception
instead of just printing a warning message, which might get lost in the
output.
This patch was generated with:
git grep -l "Bad register" *hexagon* | \
xargs sed -i "" -e 's/print("Bad register parse: "[, ]*\([^)]*\))/hex_common.bad_register(\1)/g'
Plus the bad_register() helper added to hex_common.py.
Signed-off-by: Matheus Tavares Bernardino <quic_mathbern@quicinc.com>
Reviewed-by: Anton Johansson <anjo@rev.ng>
Tested-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <1f5dbd92f68fdd89e2647e4ba527a2c32cf0f070.1683217043.git.quic_mathbern@quicinc.com>
**** Changes in v2 ****
Fix yyassert's for sign and zero extends
Coverity reports a parameter that is "set but never used". This is caused
by an assignment operator being used instead of equality.
Co-authored-by: Taylor Simpson <tsimpson@quicinc.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Anton Johansson <anjo@rev.ng>
Tested-by: Anton Johansson <anjo@rev.ng>
Message-Id: <20230428204411.1400931-1-tsimpson@quicinc.com>
**** Changes in v3 ****
Fix bugs exposed by dpmpyss_rnd_s0 instruction
Set correct size/signedness for constants
Test cases added to tests/tcg/hexagon/misc.c
**** Changes in v2 ****
Fix bug in imm_print identified in clang build
Currently, idef-parser skips all floating point instructions. However,
there are some floating point instructions that can be handled.
The following instructions are now parsed
F2_sfimm_p
F2_sfimm_n
F2_dfimm_p
F2_dfimm_n
F2_dfmpyll
F2_dfmpylh
To make these instructions work, we fix some bugs in parser-helpers.c
gen_rvalue_extend
gen_cast_op
imm_print
lexer properly sets size/signedness of constants
Test cases added to tests/tcg/hexagon/fpstuff.c
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Tested-by: Anton Johansson <anjo@rev.ng>
Reviewed-by: Anton Johansson <anjo@rev.ng>
Message-Id: <20230501203125.4025991-1-tsimpson@quicinc.com>
The following items in the CPUHexagonState are only used for bookkeeping
within the translation of a packet. With recent changes that eliminate
the need to free TCGv variables, these make more sense to be transient
and kept in DisasContext.
The following items are moved
dczero_addr
branch_taken
this_PC
Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230427230012.3800327-22-tsimpson@quicinc.com>
The pkt_has_store_s1 field is only used for bookkeeping helpers with
a load. With recent changes that eliminate the need to free TCGv
variables, it makes more sense to make this transient.
These helpers already take the instruction slot as an argument. We
combine the slot and pkt_has_store_s1 into a single argument called
slotval.
Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230427230012.3800327-21-tsimpson@quicinc.com>
The pred_written variable in the CPUHexagonState is only used for
bookkeeping within the translation of a packet. With recent changes
that eliminate the need to free TCGv variables, these make more sense
to be transient and kept in DisasContext.
Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230427230012.3800327-20-tsimpson@quicinc.com>
The new_pred_value array in the CPUHexagonState is only used for
bookkeeping within the translation of a packet. With recent changes
that eliminate the need to free TCGv variables, these make more sense
to be transient and kept in DisasContext.
Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230427230012.3800327-19-tsimpson@quicinc.com>
The new_value array in the CPUHexagonState is only used for bookkeeping
within the translation of a packet. With recent changes that eliminate
the need to free TCGv variables, these make more sense to be transient
and kept in DisasContext.
Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230427230012.3800327-18-tsimpson@quicinc.com>
Precursor to moving new_value from the global state to DisasContext
USR will need to stay in the global state because some helpers will
set it's value
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230427230012.3800327-17-tsimpson@quicinc.com>
The following have overrides
S2_insert
S2_insert_rp
S2_asr_r_svw_trun
A2_swiz
These instructions have semantics that write to the destination
before all the operand reads have been completed. Therefore,
the idef-parser versions were disabled with the short-circuit patch.
Test cases added to tests/tcg/hexagon/read_write_overlap.c
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230427230012.3800327-16-tsimpson@quicinc.com>
The generated helpers for HVX use pass-by-reference, so they can't
short-circuit when the reads/writes overlap. The instructions with
overrides are OK because they use tcg_gen_gvec_*.
We add a flag has_hvx_helper to DisasContext and extend gen_analyze_funcs
to set the flag when the instruction is an HVX instruction with a
generated helper.
We add an override for V6_vcombine so that it can be short-circuited
along with a test case in tests/tcg/hexagon/hvx_misc.c
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230427230012.3800327-15-tsimpson@quicinc.com>
In certain cases, we can avoid the overhead of writing to future_VRegs
and write directly to VRegs. We consider HVX reads/writes when computing
ctx->need_commit. Then, we can early-exit from gen_commit_hvx.
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230427230012.3800327-14-tsimpson@quicinc.com>
In certain cases, we can avoid the overhead of writing to hex_new_pred_value
and write directly to hex_pred. We consider predicate reads/writes when
computing ctx->need_commit. The get_result_pred() function uses this
field to decide between hex_new_pred_value and hex_pred. Then, we can
early-exit from gen_pred_writes.
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230427230012.3800327-13-tsimpson@quicinc.com>
In certain cases, we can avoid the overhead of writing to hex_new_value
and write directly to hex_gpr. We add need_commit field to DisasContext
indicating if the end-of-packet commit is needed. If it is not needed,
get_result_gpr() and get_result_gpr_pair() can return hex_gpr.
We pass the ctx->need_commit to helpers when needed.
Finally, we can early-exit from gen_reg_writes during packet commit.
There are a few instructions whose semantics write to the result before
reading all the inputs. Therefore, the idef-parser generated code is
incompatible with short-circuit. We tell idef-parser to skip them.
For debugging purposes, we add a cpu property to turn off short-circuit.
When the short-circuit property is false, we skip the analysis and force
the end-of-packet commit.
Here's a simple example of the TCG generated for
0x004000b4: 0x7800c020 { R0 = #0x1 }
BEFORE:
---- 004000b4
movi_i32 new_r0,$0x1
mov_i32 r0,new_r0
AFTER:
---- 004000b4
movi_i32 r0,$0x1
This patch reintroduces a use of check_for_attrib, so we remove the
G_GNUC_UNUSED added earlier in this series.
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Brian Cain <bcain@quicinc.com>
Message-Id: <20230427230012.3800327-12-tsimpson@quicinc.com>
Have gen_analyze_funcs mark the registers that are read by the
instruction. We also mark the implicit reads using instruction
attributes.
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230427230012.3800327-11-tsimpson@quicinc.com>
When generating TCG, make sure we have read all the operand registers
before writing to the destination registers.
This is a prerequesite for short-circuiting where the source and dest
operands could be the same.
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230427230012.3800327-10-tsimpson@quicinc.com>
Only endloop instructions will conditionally write to a predicate.
When there is an endloop instruction, we preload the values into
new_pred_value.
The only place pred_written is needed is when HEX_DEBUG is on.
We remove the last use of check_for_attrib. However, new uses will be
introduced later in this series, so we mark it with G_GNUC_UNUSED.
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230427230012.3800327-9-tsimpson@quicinc.com>
These instructions have implicit writes to registers, so we don't
want them to be helpers when idef-parser is off.
The following instructions are overriden
S2_cabacdecbin
SA1_cmpeqi
Remove the log_pred_write function from op_helper.c
Remove references in macros.h
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Acked-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230427230012.3800327-8-tsimpson@quicinc.com>
