The shift instructions are rewritten instead of reusing code from the old
decoder. Rotates use CC_OP_ADCOX more extensively and generally rely
more on the optimizer, so that the code generators are shared between
the immediate-count and variable-count cases.
In particular, this makes gen_RCL and gen_RCR pretty efficient for the
count == 1 case, which becomes (apart from a few extra movs) something like:
(compute_cc_all if needed)
// save old value for OF calculation
mov cc_src2, T0
// the bulk of RCL is just this!
deposit T0, cc_src, T0, 1, TARGET_LONG_BITS - 1
// compute carry
shr cc_dst, cc_src2, length - 1
and cc_dst, cc_dst, 1
// compute overflow
xor cc_src2, cc_src2, T0
extract cc_src2, cc_src2, length - 1, 1
32-bit MUL and IMUL are also slightly more efficient on 64-bit hosts.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In the new decoder it is sometimes easier to put the segment
in T1 instead of T0, usually because another operand was loaded
by common code in T0. Genrealize gen_movl_seg_T0 to allow
using any source.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Compared to the old decoder, the main differences in translation
are for the little-used ARPL instruction. IMUL is adjusted a bit
to share more code to produce flags, but is otherwise very similar.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
While keeping decode->immediate for convenience and for 4-operand instructions,
store the immediate in X86DecodedOp as well. This enables instructions
with more than one immediate such as ENTER. It can also be used for far
calls and jumps.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Extract the code into new functions, and swap T0/T1 so that T0 corresponds
to the first immediate in the instruction stream.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Create a new wrapper for syscall/sysret, and do not go through multiple
layers of wrappers.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Instead of using s->T0 or s->T1, create a scratch register
when computing the C, NC, L or LE conditions.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Instead of using s->tmp0 or s->tmp4 as the result, just extend the cc_*
registers in place. It is harmless and, if multiple setcc instructions
are used, the optimizer will be able to remove the redundant ones.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
gen_update_cc_op must be called before control flow splits. Doing it
in gen_jmp_rel{,_csize} may hide bugs, instead assert that cc_op is
clean---even if that means a few more calls to gen_update_cc_op().
With this new invariant, setting cc_op to CC_OP_DYNAMIC is unnecessary
since the caller should have done it.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
gen_update_cc_op must be called before control flow splits. Do it
where the jump on ECX!=0 is translated.
On the other hand, remove the call before gen_jcc1, which takes care of
it already, and explain why REPZ/REPNZ need not use CC_OP_DYNAMIC---the
translation block ends before any control-flow-dependent cc_op could
be observed.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Resetting cc_op to CC_OP_DYNAMIC should be done at control flow junctions,
which is not the case here. This translation block is ending and the
only effect of calling set_cc_op() would be a discard of s->cc_srcT.
This discard is useless (it's a temporary, not a global) and in fact
prevents gen_prepare_cc from returning s->cc_srcT.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
With the introduction of TSTEQ and TSTNE the .mask field is always -1,
so remove all the now-unnecessary code.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The new conditions obviously come in handy when testing individual bits
of EFLAGS, and they make it possible to remove the .mask field of
CCPrepare.
Lowering to shift+and is done by the optimizer if necessary.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When testing the sign bit or equality to zero of a partial register, it
is useful to use a single TSTEQ or TSTNE operation. It can also be used
to test the parity flag, using bit 0 of the population count.
Do not do this for target_ulong-sized values however; the optimizer would
produce a comparison against zero anyway, and it avoids shifts by 64
which are undefined behavior.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Observed the following failure while booting the SEV-SNP guest and the
guest fails to boot with the smp parameters:
"-smp 192,sockets=1,dies=12,cores=8,threads=2".
qemu-system-x86_64: sev_snp_launch_update: SNP_LAUNCH_UPDATE ret=-5 fw_error=22 'Invalid parameter'
qemu-system-x86_64: SEV-SNP: CPUID validation failed for function 0x8000001e, index: 0x0.
provided: eax:0x00000000, ebx: 0x00000100, ecx: 0x00000b00, edx: 0x00000000
expected: eax:0x00000000, ebx: 0x00000100, ecx: 0x00000300, edx: 0x00000000
qemu-system-x86_64: SEV-SNP: failed update CPUID page
Reason for the failure is due to overflowing of bits used for "Node per
processor" in CPUID Fn8000001E_ECX. This field's width is 3 bits wide and
can hold maximum value 0x7. With dies=12 (0xB), it overflows and spills
over into the reserved bits. In the case of SEV-SNP, this causes CPUID
enforcement failure and guest fails to boot.
The PPR documentation for CPUID_Fn8000001E_ECX [Node Identifiers]
=================================================================
Bits Description
31:11 Reserved.
10:8 NodesPerProcessor: Node per processor. Read-only.
ValidValues:
Value Description
0h 1 node per processor.
7h-1h Reserved.
7:0 NodeId: Node ID. Read-only. Reset: Fixed,XXh.
=================================================================
As in the spec, the valid value for "node per processor" is 0 and rest
are reserved.
Looking back at the history of decoding of CPUID_Fn8000001E_ECX, noticed
that there were cases where "node per processor" can be more than 1. It
is valid only for pre-F17h (pre-EPYC) architectures. For EPYC or later
CPUs, the linux kernel does not use this information to build the L3
topology.
Also noted that the CPUID Function 0x8000001E_ECX is available only when
TOPOEXT feature is enabled. This feature is enabled only for EPYC(F17h)
or later processors. So, previous generation of processors do not not
enumerate 0x8000001E_ECX leaf.
There could be some corner cases where the older guests could enable the
TOPOEXT feature by running with -cpu host, in which case legacy guests
might notice the topology change. To address those cases introduced a
new CPU property "legacy-multi-node". It will be true for older machine
types to maintain compatibility. By default, it will be false, so new
decoding will be used going forward.
The documentation is taken from Preliminary Processor Programming
Reference (PPR) for AMD Family 19h Model 11h, Revision B1 Processors 55901
Rev 0.25 - Oct 6, 2022.
Cc: qemu-stable@nongnu.org
Fixes: 31ada106d8 ("Simplify CPUID_8000_001E for AMD")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=206537
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Signed-off-by: Babu Moger <babu.moger@amd.com>
Message-ID: <0ee4b0a8293188a53970a2b0e4f4ef713425055e.1714757834.git.babu.moger@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We have one job to build user binaries and one job for system.
Disable tools and docs in the user job, and disable building
the user binaries in the system job.
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The host does not have the correct libraries installed for static pie,
which causes host/guest address space interference for some tests.
There's no real gain from linking statically, so drop it.
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Match the extra inserts of INDEX_op_insn_start, fixing
the db->num_insns != 1 assert in translator_loop.
Fixes: dcd092a063 ("accel/tcg: Improve can_do_io management")
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Record the fact that we've found a breakpoint on the page
in which a TranslationBlock is running.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
If we can show that high bits of an input are zero,
then we may optimize away some comparisons.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This may be treated as a 32-bit EQ/NE comparison against 0,
which is in turn treated as a LTU/GEU comparison against 1.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The x86 isa does not have this operation, so we need an expansion.
Use the same algorithm that we use for expanding this vector
operation with integers: perform the shift with a wider type
and then mask the bits that must be zero.
This reduces the instruction count from 5 to 2.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
qemu-sparc queue
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# gpg: Signature made Mon 06 May 2024 04:40:07 AM PDT
# gpg: using RSA key CC621AB98E82200D915CC9C45BC2C56FAE0F321F
# gpg: issuer "mark.cave-ayland@ilande.co.uk"
# gpg: Good signature from "Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>" [full]
* tag 'qemu-sparc-20240506' of https://github.com/mcayland/qemu:
target/sparc: Split out do_ms16b
target/sparc: Fix FPMERGE
target/sparc: Fix FMULD8*X16
target/sparc: Fix FMUL8x16A{U,L}
target/sparc: Fix FMUL8x16
target/sparc: Fix FEXPAND
linux-user/sparc: Add more hwcap bits for sparc64
hw/sparc64: set iommu_platform=on for virtio devices attached to the sun4u machine
docs/about: Deprecate the old "UltraSparc" CPU names that contain a "+"
docs/system/target-sparc: Improve the Sparc documentation
target/sparc/cpu: Avoid spaces by default in the CPU names
target/sparc/cpu: Rename the CPU models with a "+" in their names
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Accelerator patches
- Extract page-protection definitions to page-protection.h
- Rework in accel/tcg in preparation of extracting TCG fields from CPUState
- More uses of get_task_state() in user emulation
- Xen refactors in preparation for adding multiple map caches (Juergen & Edgar)
- MAINTAINERS updates (Aleksandar and Bin)
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# gpg: Signature made Mon 06 May 2024 05:42:08 AM PDT
# gpg: using RSA key FAABE75E12917221DCFD6BB2E3E32C2CDEADC0DE
# gpg: Good signature from "Philippe Mathieu-Daudé (F4BUG) <f4bug@amsat.org>" [full]
* tag 'accel-20240506' of https://github.com/philmd/qemu: (28 commits)
MAINTAINERS: Update my email address
MAINTAINERS: Update Aleksandar Rikalo email
system: Pass RAM MemoryRegion and is_write in xen_map_cache()
xen: mapcache: Break out xen_map_cache_init_single()
xen: mapcache: Break out xen_invalidate_map_cache_single()
xen: mapcache: Refactor xen_invalidate_map_cache_entry_unlocked
xen: mapcache: Refactor xen_replace_cache_entry_unlocked
xen: mapcache: Break out xen_ram_addr_from_mapcache_single
xen: mapcache: Refactor xen_remap_bucket for multi-instance
xen: mapcache: Refactor xen_map_cache for multi-instance
xen: mapcache: Refactor lock functions for multi-instance
xen: let xen_ram_addr_from_mapcache() return -1 in case of not found entry
system: let qemu_map_ram_ptr() use qemu_ram_ptr_length()
user: Use get_task_state() helper
user: Declare get_task_state() once in 'accel/tcg/vcpu-state.h'
user: Forward declare TaskState type definition
accel/tcg: Move @plugin_mem_cbs from CPUState to CPUNegativeOffsetState
accel/tcg: Restrict cpu_plugin_mem_cbs_enabled() to TCG
accel/tcg: Restrict qemu_plugin_vcpu_exit_hook() to TCG plugins
accel/tcg: Update CPUNegativeOffsetState::can_do_io field documentation
...
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* target/i386: Introduce SapphireRapids-v3 to add missing features
* switch boards to "default y"
* allow building emulators without any board
* configs: list "implied" device groups in the default configs
* remove unnecessary declarations from typedefs.h
* target/i386: Give IRQs a chance when resetting HF_INHIBIT_IRQ_MASK
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# gpg: Signature made Fri 03 May 2024 10:36:59 AM PDT
# gpg: using RSA key F13338574B662389866C7682BFFBD25F78C7AE83
# gpg: issuer "pbonzini@redhat.com"
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>" [full]
# gpg: aka "Paolo Bonzini <pbonzini@redhat.com>" [full]
* tag 'for-upstream' of https://gitlab.com/bonzini/qemu: (46 commits)
qga/commands-posix: fix typo in qmp_guest_set_user_password
migration: do not include coroutine_int.h
kvm: move target-dependent interrupt routing out of kvm-all.c
pci: remove some types from typedefs.h
tcg: remove CPU* types from typedefs.h
display: remove GraphicHwOps from typedefs.h
qapi/machine: remove types from typedefs.h
monitor: remove MonitorDef from typedefs.h
migration: remove PostcopyDiscardState from typedefs.h
lockable: remove QemuLockable from typedefs.h
intc: remove PICCommonState from typedefs.h
qemu-option: remove QemuOpt from typedefs.h
net: remove AnnounceTimer from typedefs.h
numa: remove types from typedefs.h
qdev-core: remove DeviceListener from typedefs.h
fw_cfg: remove useless declarations from typedefs.h
build: do not build virtio-vga-gl if virgl/opengl not available
bitmap: Use g_try_new0/g_new0/g_renew
target/i386: Introduce SapphireRapids-v3 to add missing features
docs: document new convention for Kconfig board symbols
...
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Short-circuit for packets with r/w and no overlap
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# gpg: Signature made Sun 05 May 2024 04:24:15 PM PDT
# gpg: using RSA key 3D66AAE474594824C88CE0F81A54AFB8E5646C32
# gpg: Good signature from "Brian Cain (QUIC) <quic_bcain@quicinc.com>" [unknown]
# gpg: aka "Brian Cain <bcain@kernel.org>" [unknown]
# gpg: aka "Brian Cain (QuIC) <bcain@quicinc.com>" [unknown]
# gpg: aka "Brian Cain (CAF) <bcain@codeaurora.org>" [unknown]
# gpg: aka "bcain" [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: 6350 20F9 67A7 7164 79EF 49E0 175C 464E 541B 6D47
# Subkey fingerprint: 3D66 AAE4 7459 4824 C88C E0F8 1A54 AFB8 E564 6C32
* tag 'pull-hex-20240505' of https://github.com/quic/qemu:
Hexagon (target/hexagon) Remove hex_common.read_attribs_file
Hexagon (target/hexagon) Remove gen_shortcode.py
Hexagon (target/hexagon) Remove gen_op_regs.py
Hexagon (target/hexagon) Remove uses of op_regs_generated.h.inc
Hexagon (tests/tcg/hexagon) Test HVX .new read from high half of pair
Hexagon (target/hexagon) Mark has_pred_dest in trans functions
Hexagon (target/hexagon) Mark dest_idx in trans functions
Hexagon (target/hexagon) Mark new_read_idx in trans functions
Hexagon (target/hexagon) Add is_old/is_new to Register class
Hexagon (target/hexagon) Only pass env to generated helper when needed
Hexagon (target/hexagon) Pass SP explicitly to helpers that need it
Hexagon (target/hexagon) Pass P0 explicitly to helpers that need it
Hexagon (target/hexagon) Enable more short-circuit packets (HVX)
Hexagon (target/hexagon) Enable more short-circuit packets (scalar core)
Hexagon (target/hexagon) Analyze reads before writes
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Add MapCache argument to xen_replace_cache_entry_unlocked in
preparation for supporting multiple map caches.
No functional change.
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@amd.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20240430164939.925307-8-edgar.iglesias@gmail.com>
[PMD: Remove last global mapcache pointer, reported by sstabellini]
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
While each user emulation implentation defines its own
TaskState structure, both use the same get_task_state()
declaration, in particular in common code (such gdbstub).
Declare the method once in "accel/tcg/vcpu-state.h".
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20240428221450.26460-10-philmd@linaro.org>
For union types, the tag member is known only after .check().
We used to code this in a simple way: QAPISchemaVariants attribute
.tag_member was None for union types until .check().
Since this complicated typing, recent commit "qapi/schema: fix typing
for QAPISchemaVariants.tag_member" hid it behind a property.
The previous commit lets us treat .tag_member just like the other
attributes that become known only in .check(): declare, but don't
initialize it in .__init__().
Signed-off-by: Markus Armbruster <armbru@redhat.com>
QAPISchemaVariants.check()'s code is almost entirely conditional on
union vs. alternate type.
Move the conditional code to QAPISchemaBranches.check() and
QAPISchemaAlternatives.check(), where the conditions are always
satisfied.
Attribute QAPISchemaVariants.tag_name is now only used by
QAPISchemaBranches. Move it there.
Refactor the three types' .__init__() to make them a bit simpler.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
