This finally paves the way for tcg/ to be built once per mode.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Create helper-proto-common.h without the target specific portion.
Use that in tcg-op-common.h. Include helper-proto.h in target/arm
and target/hexagon before helper-info.c.inc; all other targets are
already correct in this regard.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
In preparation for compiling tcg/ only once, eliminate
the all_helpers array. Instantiate the info structs for
the generic helpers in accel/tcg/, and the structs for
the target-specific helpers in each translate.c.
Since we don't see all of the info structs at startup,
initialize at first use, using g_once_init_* to make
sure we don't race while doing so.
Reviewed-by: Anton Johansson <anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
In fcdab382c8 we removed a tcg_gen_extu_tl_i64 from gen_empty_mem_cb,
and failed to adjust the associated copy, leading to a failed assert.
Fixes: fcdab382c8 ("accel/tcg: Widen plugin_gen_empty_mem_callback to i64")
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230518145813.2940745-1-richard.henderson@linaro.org>
Since we do this inside gen_empty_mem_cb anyway, let's
do this earlier inside tcg expansion.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
As do_gen_mem_cb is called once, merge it into gen_empty_mem_cb.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
As gen_mem_wrapped is only used in plugin_gen_empty_mem_callback,
we can avoid the curiosity of union mem_gen_fn by inlining it.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Move the tcg_temp_free_* and tcg_temp_ebb_new_* declarations
and inlines to the new header. These are private to the
implementation, and will prevent tcg_temp_free_* from creeping
back into the guest front ends.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Here we are creating a temp whose value needs to be replaced,
but always storing NULL into CPUState.plugin_mem_cbs.
Use tcg_constant_ptr(0) explicitly.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
All of these uses have quite local scope.
Avoid tcg_const_*, because we haven't added a corresponding
interface for TEMP_EBB. Use explicit tcg_gen_movi_* instead.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
We were mistakenly checking tcg_ctx->plugin_insn as a canary to know
whether the TB had emitted helpers that might have accessed memory.
The problem is that tcg_ctx->plugin_insn gets updated on every
instruction in the TB, which results in us wrongly performing the
optimization (i.e. not clearing cpu->plugin_mem_cbs) way too often,
since it's not rare that the last instruction in the TB doesn't
use helpers.
Fix it by tracking a per-TB canary.
While at it, expand documentation.
Related: #1381
Signed-off-by: Emilio Cota <cota@braap.org>
Message-Id: <20230108164731.61469-2-cota@braap.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230124180127.1881110-32-alex.bennee@linaro.org>
We have been allocating a worst case number of arguments
to support calls. Instead, allow the size to vary.
By default leave space for 4 args, to maximize reuse,
but allow calls to increase the number of args to 32.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
[PMD: Split patch in two]
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20221218211832.73312-3-philmd@linaro.org>
In order to have variable size allocated TCGOp, pass the number
of arguments we use (and would allocate) up to tcg_op_alloc().
This alters tcg_emit_op(), tcg_op_insert_before() and
tcg_op_insert_after() prototypes.
In tcg_op_alloc() ensure the number of arguments is in range.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
[PMD: Extracted from bigger patch]
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20221218211832.73312-2-philmd@linaro.org>
Better to re-use the existing function for copying ops.
Acked-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
We copied all of the arguments in copy_op_nocheck.
We only need to replace the one argument that we change.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The function pointer is immediately after the output and input
operands; no need to search.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Use the pc coming from db->pc_first rather than the TB.
Use the cached host_addr rather than re-computing for the
first page. We still need a separate lookup for the second
page because it won't be computed for DisasContextBase until
the translator actually performs a read from the page.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
We can't always guarantee we get to the end of a translator loop.
Although this can happen for a variety of reasons it does happen more
often on x86 system emulation when an instruction spans across to an
un-faulted page. This caused confusion of the instruction tracking
data resulting in apparent reverse execution (at least from the
plugins point of view).
Fix this by moving the reset code to plugin_gen_tb_start so we always
start with a clean slate.
We unconditionally reset tcg_ctx->plugin_insn as the
plugin_insn_append code uses this as a proxy for knowing if plugins
are enabled for the current instruction. Otherwise we can hit a race
where a previously instrumented thread leaves a stale value after the
main thread exits and disables instrumentation.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/824
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20220204204335.1689602-27-alex.bennee@linaro.org>
Currently we make the assumption that the guest frontend loads all
op code bytes sequentially. This mostly holds up for regular fixed
encodings but some architectures like s390x like to re-read the
instruction which causes weirdness to occur. Rather than changing the
frontends make the plugin API a little more ergonomic and able to
handle the re-read case.
Stuff will still get strange if we read ahead of the opcode but so far
no front ends have done that and this patch asserts the case so we can
catch it early if they do.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211026102234.3961636-21-alex.bennee@linaro.org>
Coverity doesn't know enough about how we have arranged our plugin TCG
ops to know we will always have incremented insn_idx before injecting
the callback. Let us assert it for the benefit of Coverity and protect
ourselves from accidentally breaking the assumption and triggering
harder to grok errors deeper in the code if we attempt a negative
indexed array lookup.
However to get to this point we re-factor the code and remove the
second hand instruction boundary detection in favour of scanning the
full set of ops and using the existing INDEX_op_insn_start to cleanly
detect when the instruction has started. As we no longer need the
plugin specific list of ops we delete that.
My initial benchmarks shows no discernible impact of dropping the
plugin specific ops list.
Fixes: Coverity 1459509
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Cc: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20210917162332.3511179-12-alex.bennee@linaro.org>
Use the MemOpIdx directly, rather than the rearrangement
of the same bits currently done by the trace infrastructure.
Pass in enum qemu_plugin_mem_rw so that we are able to treat
read-modify-write operations as a single operation.
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
As noted by qemu-plugins.h, enum qemu_plugin_cb_flags is
currently unused -- plugins can neither read nor write
guest registers.
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Let the compiler decide on inlining.
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Stop including cpu.h in files that don't need it.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210416171314.2074665-4-thuth@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
When icount is enabled and we recompile an MMIO access we end up
double counting the instruction execution. To avoid this we introduce
the CF_MEMI cflag which only allows memory instrumentation for the
next TB (which won't yet have been counted). As this is part of the
hashed compile flags we will only execute the generated TB while
coming out of a cpu_io_recompile.
While we are at it delete the old TODO. We might as well keep the
translation handy as it's likely you will repeatedly hit it on each
MMIO access.
Reported-by: Aaron Lindsay <aaron@os.amperecomputing.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Tested-by: Aaron Lindsay <aaron@os.amperecomputing.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210213130325.14781-21-alex.bennee@linaro.org>
A recent change to the handling of constants in TCG changed the
pattern of ops emitted for a constant add. We no longer emit a mov and
the constant can be applied directly to the TCG_op_add arguments. This
was causing SEGVs when running the insn plugin with arg=inline. Fix
this by updating copy_add_i64 to do the right thing while also adding
a comment at the top of the append section as an aide memoir if
something like this happens again.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Cc: Emilio G. Cota <cota@braap.org>
Message-Id: <20210213130325.14781-10-alex.bennee@linaro.org>
We first inject empty instrumentation from translator_loop.
After translation, we go through the plugins to see what
they want to register for, filling in the empty instrumentation.
If if turns out that some instrumentation remains unused, we
remove it.
This approach supports the following features:
- Inlining TCG code for simple operations. Note that we do not
export TCG ops to plugins. Instead, we give them a C API to
insert inlined ops. So far we only support adding an immediate
to a u64, e.g. to count events.
- "Direct" callbacks. These are callbacks that do not go via
a helper. Instead, the helper is defined at run-time, so that
the plugin code is directly called from TCG. This makes direct
callbacks as efficient as possible; they are therefore used
for very frequent events, e.g. memory callbacks.
- Passing the host address to memory callbacks. Most of this
is implemented in a later patch though.
- Instrumentation of memory accesses performed from helpers.
See the corresponding comment, as well as a later patch.
Signed-off-by: Emilio G. Cota <cota@braap.org>
[AJB: add alloc_tcg_plugin_context, use glib, rm hwaddr]
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
