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>
Will gain a user soon.
Signed-off-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
We are going to re-use mem_info later for plugins and will need to
track the mmu_idx for softmmu code.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
These new instructions are conditional on MSR.VEC for TX=1,
so we can consider these Altivec instructions.
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
These new instructions are a mix of those like LXSD that are
only conditional only on MSR.VEC and those like LXV that are
conditional on MSR.VEC for TX=1. Thus, in the end, we can
consider all of these as Altivec instructions.
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
These new instructions are conditional only on MSR.VEC and
are thus part of the Altivec instruction set, and not VSX.
This includes negation and compare not equal.
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
These new instructions are conditional on MSR.FP when TX=0 and
MSR.VEC when TX=1. Since we only care about the Altivec registers,
and force TX=1, we can consider these to be Altivec instructions.
Since Altivec is true for any use of vector types, we only need
test have_isa_2_07.
This includes moves to and from the integer registers.
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
These new instructions are conditional only on MSR.VSX and
are thus part of the VSX instruction set, and not Altivec.
This includes double-word loads and stores.
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
These new instructions are conditional only on MSR.VEC and
are thus part of the Altivec instruction set, and not VSX.
This includes lots of double-word arithmetic and a few extra
logical operations.
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The VSX instruction set instructions include double-word loads and
stores, double-word load and splat, double-word permute, and bit
select. All of which require multiple operations in the Altivec
instruction set.
Because the VSX registers map %vsr32 to %vr0, and we have no current
intention or need to use vector registers outside %vr0-%vr19, force
on the {ax,bx,cx,tx} bits within the added VSX insns so that we don't
have to otherwise modify the VR[TABC] macros.
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Now that we have implemented the required tcg operations,
we can enable detection of host vector support.
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk> (PPC32)
Reviewed-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This is only used for 32-bit hosts.
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Aleksandar Markovic <amarkovic@wavecomp.com>
For Altivec, this is always an expansion.
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Aleksandar Markovic <amarkovic@wavecomp.com>
For Altivec, this is done via vector shift by vector,
and loading the immediate into a register.
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Add support for vector saturated add/subtract using Altivec
instructions:
VADDSBS, VADDSHS, VADDSWS, VADDUBS, VADDUHS, VADDUWS, and
VSUBSBS, VSUBSHS, VSUBSWS, VSUBUBS, VSUBUHS, VSUBUWS.
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Add support for vector add/subtract using Altivec instructions:
VADDUBM, VADDUHM, VADDUWM, VSUBUBM, VSUBUHM, VSUBUWM.
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Add support for vector maximum/minimum using Altivec instructions
VMAXSB, VMAXSH, VMAXSW, VMAXUB, VMAXUH, VMAXUW, and
VMINSB, VMINSH, VMINSW, VMINUB, VMINUH, VMINUW.
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Add various bits and peaces related mostly to load and store
operations. In that context, logic, compare, and splat Altivec
instructions are used, and, therefore, the support for emitting
them is included in this patch too.
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Introduce all of the flags required to enable tcg backend vector support,
and a runtime flag to indicate the host supports Altivec instructions.
For now, do not actually set have_isa_altivec to true, because we have not
yet added all of the code to actually generate all of the required insns.
However, we must define these flags in order to disable ifndefs that create
stub versions of the functions added here.
The change to tcg_out_movi works around a buglet in tcg.c wherein if we
do not define tcg_out_dupi_vec we get a declared but not defined Werror,
but if we only declare it we get a defined but not used Werror. We need
to this change to tcg_out_movi eventually anyway, so it's no biggie.
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Previously we've been hard-coding knowledge that Power7 has ISEL, but
it was an optional instruction before that. Use the AT_HWCAP2 bit,
when present, to properly determine support.
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This is identical to have_isa_2_06, so replace it.
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Introduce an enum to hold base < 2.06 < 3.00. Use macros to
preserve the existing have_isa_2_06 and have_isa_3_00 predicates.
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Introduce macros VRT(), VRA(), VRB(), VRC() used for encoding
elements of Altivec instructions.
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Introduce macro VX4() used for encoding Altivec instructions.
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Altivec supports 32 128-bit vector registers, whose names are
by convention v0 through v31.
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Reorganize watchpoints out of i/o path.
Return host address from probe_write / probe_access.
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Merge remote-tracking branch 'remotes/rth/tags/pull-tcg-20190903' into staging
Allow page table bit to swap endianness.
Reorganize watchpoints out of i/o path.
Return host address from probe_write / probe_access.
# gpg: Signature made Tue 03 Sep 2019 16:47:50 BST
# gpg: using RSA key 7A481E78868B4DB6A85A05C064DF38E8AF7E215F
# gpg: issuer "richard.henderson@linaro.org"
# gpg: Good signature from "Richard Henderson <richard.henderson@linaro.org>" [full]
# Primary key fingerprint: 7A48 1E78 868B 4DB6 A85A 05C0 64DF 38E8 AF7E 215F
* remotes/rth/tags/pull-tcg-20190903: (36 commits)
tcg: Factor out probe_write() logic into probe_access()
tcg: Make probe_write() return a pointer to the host page
s390x/tcg: Pass a size to probe_write() in do_csst()
hppa/tcg: Call probe_write() also for CONFIG_USER_ONLY
mips/tcg: Call probe_write() for CONFIG_USER_ONLY as well
tcg: Enforce single page access in probe_write()
tcg: Factor out CONFIG_USER_ONLY probe_write() from s390x code
s390x/tcg: Fix length calculation in probe_write_access()
s390x/tcg: Use guest_addr_valid() instead of h2g_valid() in probe_write_access()
tcg: Check for watchpoints in probe_write()
cputlb: Handle watchpoints via TLB_WATCHPOINT
cputlb: Remove double-alignment in store_helper
cputlb: Fix size operand for tlb_fill on unaligned store
exec: Factor out cpu_watchpoint_address_matches
cputlb: Fold TLB_RECHECK into TLB_INVALID_MASK
exec: Factor out core logic of check_watchpoint()
exec: Move user-only watchpoint stubs inline
target/sparc: sun4u Invert Endian TTE bit
target/sparc: Add TLB entry with attributes
cputlb: Byte swap memory transaction attribute
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Preparation for collapsing the two byte swaps, adjust_endianness and
handle_bswap, along the I/O path.
Target dependant attributes are conditionalized upon NEED_CPU_H.
Signed-off-by: Tony Nguyen <tony.nguyen@bt.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <81d9cd7d7f5aaadfa772d6c48ecee834e9cf7882.1566466906.git.tony.nguyen@bt.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Afterwise is "wise after the fact", as in "hindsight".
Here we meant "afterwards" (as in "subsequently"). Fix it.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20190828165307.18321-7-alex.bennee@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This patch moves the define of target access alignment earlier from
target/foo/cpu.h to configure.
Suggested in Richard Henderson's reply to "[PATCH 1/4] tcg: TCGMemOp is now
accelerator independent MemOp"
Signed-off-by: Tony Nguyen <tony.nguyen@bt.com>
Message-Id: <11e818d38ebc40e986cfa62dd7d0afdc@tpw09926dag18e.domain1.systemhost.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: tony.nguyen@bt.com <tony.nguyen@bt.com>
In my "build everything" tree, changing qemu/main-loop.h triggers a
recompile of some 5600 out of 6600 objects (not counting tests and
objects that don't depend on qemu/osdep.h). It includes block/aio.h,
which in turn includes qemu/event_notifier.h, qemu/notify.h,
qemu/processor.h, qemu/qsp.h, qemu/queue.h, qemu/thread-posix.h,
qemu/thread.h, qemu/timer.h, and a few more.
Include qemu/main-loop.h only where it's needed. Touching it now
recompiles only some 1700 objects. For block/aio.h and
qemu/event_notifier.h, these numbers drop from 5600 to 2800. For the
others, they shrink only slightly.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190812052359.30071-21-armbru@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
migration/qemu-file.h neglects to include it even though it needs
ram_addr_t. Fix that. Drop a few superfluous inclusions elsewhere.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20190812052359.30071-14-armbru@redhat.com>
This patch fixes two problems:
(1) The inputs to the EXTR insn were reversed,
(2) The input constraints use rZ, which means that we need to use
the REG0 macro in order to supply XZR for a constant 0 input.
Fixes: 464c2969d5
Reported-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
On a 64-bit host, discard any replications of the 32-bit
sign bit when performing the shift and merge.
Fixes: https://bugs.launchpad.net/bugs/1834496
Tested-by: Christophe Lyon <christophe.lyon@linaro.org>
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This operation can always be emitted, even if we need to
fall back to xor. Adjust the assertions to match.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Commit 269bd5d8 "cpu: Move the softmmu tlb to CPUNegativeOffsetState'
broke the RISC-V host build as there are two variables that are used but
not defined.
This patch renames the undefined variables mask_off and table_off to the
existing (but unused) mask_ofs and table_ofs variables.
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <79729cc88ca509e08b5c4aa0aa8a52847af70c0f.1561039316.git.alistair.francis@wdc.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Basically, the context could get the MachineState reference via call
chains or unrecommended qdev_get_machine() in !CONFIG_USER_ONLY mode.
A local variable of the same name would be introduced in the declaration
phase out of less effort OR replace it on the spot if it's only used
once in the context. No semantic changes.
Signed-off-by: Like Xu <like.xu@linux.intel.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20190518205428.90532-4-like.xu@linux.intel.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
No header includes qemu-common.h after this commit, as prescribed by
qemu-common.h's file comment.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190523143508.25387-5-armbru@redhat.com>
[Rebased with conflicts resolved automatically, except for
include/hw/arm/xlnx-zynqmp.h hw/arm/nrf51_soc.c hw/arm/msf2-soc.c
block/qcow2-refcount.c block/qcow2-cluster.c block/qcow2-cache.c
target/arm/cpu.h target/lm32/cpu.h target/m68k/cpu.h target/mips/cpu.h
target/moxie/cpu.h target/nios2/cpu.h target/openrisc/cpu.h
target/riscv/cpu.h target/tilegx/cpu.h target/tricore/cpu.h
target/unicore32/cpu.h target/xtensa/cpu.h; bsd-user/main.c and
net/tap-bsd.c fixed up]
There was nothing armv7 specific about the bic+cmp sequence, however
looking at the set of guests more closely shows that the 8-bit immediate
operand for the bic can only be satisfied with one guest in tree:
baseline m-profile -- 10-bit pages with aligned 4-byte memory ops.
Therefore it does not seem useful to keep this path.
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This changes the code generation for the tlb from e.g.
ldr ip, [r6, #-0x10]
ldr r2, [r6, #-0xc]
and ip, ip, r4, lsr #8
ldrd r0, r1, [r2, ip]!
ldr r2, [r2, #0x18]
to
ldrd r0, r1, [r6, #-0x10]
and r0, r0, r4, lsr #8
ldrd r2, r3, [r1, r0]!
ldr r1, [r1, #0x18]
for armv7 hosts. Rearranging the register allocation in
order to avoid overlap between the two ldrd pairs causes
the patch to be larger than it ordinarily would be.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
We have for some time had code within the tcg backends to
handle large positive offsets from env. This move makes
sure that need not happen. Indeed, we are able to assert
at build time that simple offsets suffice for all hosts.
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Move all softmmu tlb data into this structure. Arrange the
members so that we are able to place mask+table together and
at a smaller absolute offset from ENV.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This instruction raises #GP, aka SIGSEGV, if the effective address
is not aligned to 16-bytes.
We have assertions in tcg-op-gvec.c that the offset from ENV is
aligned, for vector types <= V128. But the offset itself does not
validate that the final pointer is aligned -- one must also remember
to use the QEMU_ALIGNED() attribute on the vector member within ENV.
PowerPC Altivec has vector load/store instructions that silently
discard the low 4 bits of the address, making alignment mistakes
difficult to discover. Aid that by making the most popular host
visibly signal the error.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The allows immediates to be used for ORR and BIC,
as well as the trivial inversions, ORC and AND.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Use MOVI+ORR or MVNI+BIC in order to build some vector constants,
as opposed to dropping them to the constant pool. This includes
all 16-bit constants and a similar set of 32-bit constants.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
There are several sub-classes of vector immediate, and only MOVI
can use them all. This will enable usage of MVNI and ORRI, which
use progressively fewer sub-classes.
This patch adds no new functionality, merely splits the function
and moves part of the logic into tcg_out_dupi_vec.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The instruction set has 3 insns that perform the same operation,
only varying in which operand must overlap the destination. We
can represent the operation without overlap and choose based on
the operands seen.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Using umin(a, b) == a as an expansion for TCG_COND_LEU is a
better alternative to (a - INT_MIN) <= (b - INT_MIN).
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
