Our current usage of MMU indexes when EL3 is AArch32 is confused.
Architecturally, when EL3 is AArch32, all Secure code runs under the
Secure PL1&0 translation regime:
* code at EL3, which might be Mon, or SVC, or any of the
other privileged modes (PL1)
* code at EL0 (Secure PL0)
This is different from when EL3 is AArch64, in which case EL3 is its
own translation regime, and EL1 and EL0 (whether AArch32 or AArch64)
have their own regime.
We claimed to be mapping Secure PL1 to our ARMMMUIdx_EL3, but didn't
do anything special about Secure PL0, which meant it used the same
ARMMMUIdx_EL10_0 that NonSecure PL0 does. This resulted in a bug
where arm_sctlr() incorrectly picked the NonSecure SCTLR as the
controlling register when in Secure PL0, which meant we were
spuriously generating alignment faults because we were looking at the
wrong SCTLR control bits.
The use of ARMMMUIdx_EL3 for Secure PL1 also resulted in the bug that
we wouldn't honour the PAN bit for Secure PL1, because there's no
equivalent _PAN mmu index for it.
Fix this by adding two new MMU indexes:
* ARMMMUIdx_E30_0 is for Secure PL0
* ARMMMUIdx_E30_3_PAN is for Secure PL1 when PAN is enabled
The existing ARMMMUIdx_E3 is used to mean "Secure PL1 without PAN"
(and would be named ARMMMUIdx_E30_3 in an AArch32-centric scheme).
These extra two indexes bring us up to the maximum of 16 that the
core code can currently support.
This commit:
* adds the new MMU index handling to the various places
where we deal in MMU index values
* adds assertions that we aren't AArch32 EL3 in a couple of
places that currently use the E10 indexes, to document why
they don't also need to handle the E30 indexes
* documents in a comment why regime_has_2_ranges() doesn't need
updating
Notes for backporting: this commit depends on the preceding revert of
4c2c04746932; that revert and this commit should probably be
backported to everywhere that we originally backported 4c2c047469.
Cc: qemu-stable@nongnu.org
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2326
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2588
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20241101142845.1712482-3-peter.maydell@linaro.org
This reverts commit 4c2c047469.
This commit tried to fix a problem with our usage of MMU indexes when
EL3 is AArch32, using what it described as a "more complicated
approach" where we share the same MMU index values for Secure PL1&0
and NonSecure PL1&0. In theory this should work, but the change
didn't account for (at least) two things:
(1) The design change means we need to flush the TLBs at any point
where the CPU state flips from one to the other. We already flush
the TLB when SCR.NS is changed, but we don't flush the TLB when we
take an exception from NS PL1&0 into Mon or when we return from Mon
to NS PL1&0, and the commit didn't add any code to do that.
(2) The ATS12NS* address translate instructions allow Mon code (which
is Secure) to do a stage 1+2 page table walk for NS. I thought this
was OK because do_ats_write() does a page table walk which doesn't
use the TLBs, so because it can pass both the MMU index and also an
ARMSecuritySpace argument we can tell the table walk that we want NS
stage1+2, not S. But that means that all the code within the ptw
that needs to find e.g. the regime EL cannot do so only with an
mmu_idx -- all these functions like regime_sctlr(), regime_el(), etc
would need to pass both an mmu_idx and the security_space, so they
can tell whether this is a translation regime controlled by EL1 or
EL3 (and so whether to look at SCTLR.S or SCTLR.NS, etc).
In particular, because regime_el() wasn't updated to look at the
ARMSecuritySpace it would return 1 even when the CPU was in Monitor
mode (and the controlling EL is 3). This meant that page table walks
in Monitor mode would look at the wrong SCTLR, TCR, etc and would
generally fault when they should not.
Rather than trying to make the complicated changes needed to rescue
the design of 4c2c047469, we revert it in order to instead take the
route that that commit describes as "the most straightforward" fix,
where we add new MMU indexes EL30_0, EL30_3, EL30_3_PAN to correspond
to "Secure PL1&0 at PL0", "Secure PL1&0 at PL1", and "Secure PL1&0 at
PL1 with PAN".
This revert will re-expose the "spurious alignment faults in
Secure PL0" issue #2326; we'll fix it again in the next commit.
Cc: qemu-stable@nongnu.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Thomas Huth <thuth@redhat.com>
Message-id: 20241101142845.1712482-2-peter.maydell@linaro.org
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Set the NaN propagation rule explicitly for the float_status word
used in the rx target.
This not the architecturally correct behaviour, but since this is a
no-behaviour-change patch, we leave a TODO note to that effect.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20241025141254.2141506-21-peter.maydell@linaro.org
Set the NaN propagation rule explicitly for the float_status word
used in the openrisc target.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20241025141254.2141506-20-peter.maydell@linaro.org
Set the NaN propagation rule explicitly for the float_status word
used in the microblaze target.
This is probably not the architecturally correct behaviour,
but since this is a no-behaviour-change patch, we leave a
TODO note to that effect.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20241025141254.2141506-19-peter.maydell@linaro.org
Although the floating point rounding mode for Microblaze is always
nearest-even, we cannot set it just once in the CPU initfn. This is
because env->fp_status is in the part of the CPU state struct that is
zeroed on reset.
Move the call to set_float_rounding_mode() into the reset fn.
(This had no guest-visible effects because it happens that the
float_round_nearest_even enum value is 0, so when the struct was
zeroed it didn't corrupt the setting.)
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20241025141254.2141506-18-peter.maydell@linaro.org
Set the NaN propagation rule explicitly for the float_status word
used in this target.
This is a no-behaviour-change commit, so we retain the existing
behaviour of x87-style pick-largest-significand NaN propagation.
This is however not the architecturally correct handling, so we leave
a TODO note to that effect.
We also leave a TODO note pointing out that all this code in the cpu
initfn (including the existing setting up of env->flags and the FPCR)
should be in a currently non-existent CPU reset function.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20241025141254.2141506-17-peter.maydell@linaro.org
Set the NaN propagation rule explicitly for the float_status words
used in the x86 target.
This is a no-behaviour-change commit, so we retain the existing
behaviour of using the x87-style "prefer QNaN over SNaN, then prefer
the NaN with the larger significand" for MMX and SSE. This is
however not the documented hardware behaviour, so we leave a TODO
note about what we should be doing instead.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20241025141254.2141506-16-peter.maydell@linaro.org
Set the NaN propagation rule explicitly in xtensa_use_first_nan().
(When we convert the softfloat pickNaNMulAdd routine to also
select a NaN propagation rule at runtime, we will be able to
remove the use_first_nan flag because the propagation rules
will handle everything.)
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Max Filippov <jcmvbkbc@gmail.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20241025141254.2141506-15-peter.maydell@linaro.org
In xtensa we currently call set_use_first_nan() in a lot of
places where we want to switch the NaN-propagation handling.
We're about to change the softfloat API we use to do that,
so start by factoring all the calls out into a single
xtensa_use_first_nan() function.
The bulk of this change was done with
sed -i -e 's/set_use_first_nan(\([^,]*\),[^)]*)/xtensa_use_first_nan(env, \1)/' target/xtensa/fpu_helper.c
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Max Filippov <jcmvbkbc@gmail.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20241025141254.2141506-14-peter.maydell@linaro.org
Set the NaN propagation rule explicitly in the float_status
words we use.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20241025141254.2141506-13-peter.maydell@linaro.org
Currently we call cpu_put_fsr(0) in sparc_cpu_realizefn(), which
initializes various fields in the CPU struct:
* fsr_cexc_ftt
* fcc[]
* fsr_qne
* fsr
It also sets the rounding mode in env->fp_status.
This is largely pointless, because when we later reset the CPU
this will zero out all the fields up until the "end_reset_fields"
label, which includes all of these (but not fp_status!)
Move the cpu_put_fsr(env, 0) call to reset, because that expresses
the logical requirement: we want to reset FSR to 0 on every reset.
This isn't a behaviour change because the fields are all zero anyway.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20241025141254.2141506-12-peter.maydell@linaro.org
In cf_fpu_gdb_get_reg() and cf_fpu_gdb_set_reg() we use a temporary
float_status variable to pass to floatx80_to_float64() and
float64_to_floatx80(), but we don't initialize it, meaning that those
functions could access uninitialized data. Zero-init the structs.
(We don't need to set a NaN-propagation rule here because we
don't use these with a 2-argument fpu operation.)
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20241025141254.2141506-11-peter.maydell@linaro.org
Explicitly set the 2-NaN propagation rule on env->fp_status
and on the temporary fp_status that we use in frem (since
we pass that to a division operation function).
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Set the 2-NaN propagation rule explicitly in env->fp_status
and env->vec_status.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20241025141254.2141506-9-peter.maydell@linaro.org
Set the 2-NaN propagation rule explicitly in env->fpu_status.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20241025141254.2141506-8-peter.maydell@linaro.org
Set the 2-NaN propagation rule explicitly in env->fp_status.
Really we only need to do this at CPU reset (after reset has zeroed
out most of the CPU state struct, which typically includes fp_status
fields). However target/hppa does not currently implement CPU reset
at all, so leave a TODO comment to note that this could be moved if
we ever do implement reset.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20241025141254.2141506-7-peter.maydell@linaro.org
Set the 2-NaN propagation rule explicitly in the float_status word we
use.
(There are a couple of places in fpu_helper.c where we create a
dummy float_status word with "float_status *s = { };", but these
are only used for calling float*_is_quiet_nan() so it doesn't
matter that we don't set a 2-NaN propagation rule there.)
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20241025141254.2141506-6-peter.maydell@linaro.org
Set the 2-NaN propagation rule explicitly in the float_status words
we use.
For active_fpu.fp_status, we do this in a new fp_reset() function
which mirrors the existing msa_reset() function in doing "first call
restore to set the fp status parts that depend on CPU state, then set
the fp status parts that are constant".
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20241025141254.2141506-5-peter.maydell@linaro.org
Set the 2-NaN propagation rule explicitly in the float_status words
we use. We wrap this plus the pre-existing setting of the
tininess-before-rounding flag in a new function
arm_set_default_fp_behaviours() to avoid repetition, since we have a
lot of float_status words at this point.
The situation with FPA11 emulation in linux-user is a little odd, and
arguably "correct" behaviour there would be to exactly match a real
Linux kernel's FPA11 emulation. However FPA11 emulation is
essentially dead at this point and so it seems better to continue
with QEMU's current behaviour and leave a comment describing the
situation.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20241025141254.2141506-4-peter.maydell@linaro.org
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Merge tag 'pull-loongarch-20241102' of https://gitlab.com/gaosong/qemu into staging
pull-loongarch-20241102
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# gpg: Signature made Sat 02 Nov 2024 07:57:18 GMT
# gpg: using RSA key B8FF1DA0D2FDCB2DA09C6C2C40A2FFF239263EDF
# gpg: Good signature from "Song Gao <m17746591750@163.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: B8FF 1DA0 D2FD CB2D A09C 6C2C 40A2 FFF2 3926 3EDF
* tag 'pull-loongarch-20241102' of https://gitlab.com/gaosong/qemu:
target/loongarch: Add steal time support on migration
hw/loongarch/boot: Use warn_report when no kernel filename
linux-headers: Update to Linux v6.12-rc5
linux-headers: loongarch: Add kvm_para.h
linux-headers: Add unistd_64.h
target/loongarch/kvm: Implement LoongArch PMU extension
target/loongarch: Implement lbt registers save/restore function
target/loongarch: Add loongson binary translation feature
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
With pv steal time supported, VM machine needs get physical address
of each vcpu and notify new host during migration. Here two
functions kvm_get_stealtime/kvm_set_stealtime, and guest steal time
physical address is only updated on KVM_PUT_FULL_STATE stage.
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Reviewed-by: Song Gao <gaosong@loongson.cn>
Message-Id: <20240930064040.753929-1-maobibo@loongson.cn>
Signed-off-by: Song Gao <gaosong@loongson.cn>
Implement PMU extension for LoongArch kvm mode. Use OnOffAuto type
variable pmu to check the PMU feature. If the PMU Feature is not supported
with KVM host, it reports error if there is pmu=on command line.
If there is no any command line about pmu parameter, it checks whether
KVM host supports the PMU Feature and set the corresponding value in cpucfg.
This patch is based on lbt patch located at
https://lore.kernel.org/qemu-devel/20240904061859.86615-1-maobibo@loongson.cn
Co-developed-by: Song Gao <gaosong@loongson.cn>
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Reviewed-by: Song Gao <gaosong@loongson.cn>
Message-Id: <20240918082315.2345034-1-maobibo@loongson.cn>
Signed-off-by: Song Gao <gaosong@loongson.cn>
Six registers scr0 - scr3, eflags and ftop are added in percpu vmstate.
And two functions kvm_loongarch_get_lbt/kvm_loongarch_put_lbt are added
to save/restore lbt registers.
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Reviewed-by: Song Gao <gaosong@loongson.cn>
Message-Id: <20240929070405.235200-3-maobibo@loongson.cn>
Signed-off-by: Song Gao <gaosong@loongson.cn>
Loongson Binary Translation (LBT) is used to accelerate binary
translation, which contains 4 scratch registers (scr0 to scr3), x86/ARM
eflags (eflags) and x87 fpu stack pointer (ftop).
Now LBT feature is added in kvm mode, not supported in TCG mode since
it is not emulated. Feature variable lbt is added with OnOffAuto type,
If lbt feature is not supported with KVM host, it reports error if there
is lbt=on command line.
If there is no any command line about lbt parameter, it checks whether
KVM host supports lbt feature and set the corresponding value in cpucfg.
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Reviewed-by: Song Gao <gaosong@loongson.cn>
Message-Id: <20240929070405.235200-2-maobibo@loongson.cn>
Signed-off-by: Song Gao <gaosong@loongson.cn>
AVX10 state enumeration in CPUID leaf D and enabling in XCR0 register
are identical to AVX512 state regardless of the supported vector lengths.
Given that some E-cores will support AVX10 but not support AVX512, add
AVX512 state components to guest when AVX10 is enabled.
Based on a patch by Tao Su <tao1.su@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Tested-by: Xuelian Guo <xuelian.guo@intel.com>
Signed-off-by: Tao Su <tao1.su@linux.intel.com>
Link: https://lore.kernel.org/r/20241031085233.425388-8-tao1.su@linux.intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Since the highest supported vector length for a processor implies that
all lesser vector lengths are also supported, add the dependencies of
the supported vector lengths. If all vector lengths aren't supported,
clear AVX10 enable bit as well.
Note that the order of AVX10 related dependencies should be kept as:
CPUID_24_0_EBX_AVX10_128 -> CPUID_24_0_EBX_AVX10_256,
CPUID_24_0_EBX_AVX10_256 -> CPUID_24_0_EBX_AVX10_512,
CPUID_24_0_EBX_AVX10_VL_MASK -> CPUID_7_1_EDX_AVX10,
CPUID_7_1_EDX_AVX10 -> CPUID_24_0_EBX,
so that prevent user from setting weird CPUID combinations, e.g. 256-bits
and 512-bits are supported but 128-bits is not, no vector lengths are
supported but AVX10 enable bit is still set.
Since AVX10_128 will be reserved as 1, adding these dependencies has the
bonus that when user sets -cpu host,-avx10-128, CPUID_7_1_EDX_AVX10 and
CPUID_24_0_EBX will be disabled automatically.
Tested-by: Xuelian Guo <xuelian.guo@intel.com>
Signed-off-by: Tao Su <tao1.su@linux.intel.com>
Link: https://lore.kernel.org/r/20241028024512.156724-5-tao1.su@linux.intel.com
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Link: https://lore.kernel.org/r/20241031085233.425388-7-tao1.su@linux.intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When AVX10 enable bit is set, the 0x24 leaf will be present as "AVX10
Converged Vector ISA leaf" containing fields for the version number and
the supported vector bit lengths.
Introduce avx10-version property so that avx10 version can be controlled
by user and cpu model. Per spec, avx10 version can never be 0, the default
value of avx10-version is set to 0 to determine whether it is specified by
user. The default can come from the device model or, for the max model,
from KVM's reported value.
Signed-off-by: Tao Su <tao1.su@linux.intel.com>
Link: https://lore.kernel.org/r/20241028024512.156724-3-tao1.su@linux.intel.com
Link: https://lore.kernel.org/r/20241028024512.156724-4-tao1.su@linux.intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Tested-by: Xuelian Guo <xuelian.guo@intel.com>
Link: https://lore.kernel.org/r/20241031085233.425388-5-tao1.su@linux.intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Prepare for filtering non-boolean features such as AVX10 version.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Signed-off-by: Tao Su <tao1.su@linux.intel.com>
Link: https://lore.kernel.org/r/20241031085233.425388-4-tao1.su@linux.intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Right now, QEMU is using the "feature" and "bits" fields of ExtSaveArea
to query the accelerator for the support status of extended save areas.
This is a problem for AVX10, which attaches two feature bits (AVX512F
and AVX10) to the same extended save states.
To keep the AVX10 hacks to the minimum, limit usage of esa->features
and esa->bits. Instead, just query the accelerator for the 0xD leaf.
Do it in common code and clear esa->size if an extended save state is
unsupported.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Link: https://lore.kernel.org/r/20241031085233.425388-3-tao1.su@linux.intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This gives greater opportunity for reassociation on x86 targets,
since addition can use the LEA instruction.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
If the operands of the arithmetic instruction fit within a half-register,
it's easiest to use a comparison instruction to compute the carry.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This removes the 256 byte parity table from the executable.
Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This makes it easier for the compiler to understand which bits are set,
and it also removes "cltq" instructions to canonicalize the output value
as 32-bit signed.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Mostly used for TEST+JG and TEST+JLE, but it is easy to cover
also JBE/JA and JL/JGE; shaves about 0.5% TCG ops.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Most uses of CC_OP_DYNAMIC are for CMP/JB/JE or similar sequences.
We can optimize many of them to avoid computation of the flags.
This eliminates both TCG ops to set up the new cc_op, and helper
instructions because evaluating just ZF is much cheaper.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Assert that op is known and that cc_op_live_ is populated.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Replace arithmetic on cc_op with a helper function.
Assert that the op has a size and that it is valid
for the configuration.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Link: https://lore.kernel.org/r/20240701025115.1265117-6-richard.henderson@linaro.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Give the first few enumerators explicit integer constants,
align the BWLQ enumerators.
This will be used to simplify ((op - CC_OP_*B) & 3).
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Link: https://lore.kernel.org/r/20240701025115.1265117-4-richard.henderson@linaro.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Just use CC_OP_EFLAGS; it is not that likely that the flags computed by
CC_OP_CLR survive the end of the basic block, in which case there is no
need to spill cc_op_src.
cc_op_src now does need spilling if the XOR is followed by a memory
operation, but this only costs 0.2% extra TCG ops. They will be recouped
by simplifications in how QEMU evaluates ZF at runtime, which are even
greater with this change.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Make const. Use the read-only strings directly; do not copy
them into an on-stack buffer with snprintf. Allow for holes
in the cc_op_str array, now present with CC_OP_POPCNT.
Fixes: 460231ad36 ("target/i386: give CC_OP_POPCNT low bits corresponding to MO_TL")
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Link: https://lore.kernel.org/r/20240701025115.1265117-2-richard.henderson@linaro.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Prefer it to gen_ext_tl in the common case where the destination is known.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The call to xgetbv() is passing the ecx value for cpuid function 0xD,
index 0. The xgetbv call thus returns false (OSXSAVE is bit 27, which is
well out of the range of CPUID[0xD,0].ECX) and eax is not modified. While
fixing it, cache the whole computation of supported XCR0 bits since it
will be used for more than just CPUID leaf 0xD.
Furthermore, unsupported subleafs of CPUID 0xD (including all those
corresponding to zero bits in host's XCR0) must be hidden; if OSXSAVE
is not set at all, the whole of CPUID leaf 0xD plus the XSAVE bit must
be hidden.
Finally, unconditionally drop XSTATE_BNDREGS_MASK and XSTATE_BNDCSR_MASK;
real hardware will only show them if the MPX bit is set in CPUID;
this is never the case for hvf_get_supported_cpuid() because QEMU's
Hypervisor.framework support does not handle the VMX fields related to
MPX (even in the unlikely possibility that the host has MPX enabled).
So hide those bits in the new cache_host_xcr0().
Cc: Phil Dennis-Jordan <lists@philjordan.eu>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Newer AMD CPUs support ERAPS (Enhanced Return Address Prediction Security)
feature that enables the auto-clear of RSB entries on a TLB flush, context
switches and VMEXITs. The number of default RSP entries is reflected in
RapSize.
Add the feature bit and feature word to support these features.
CPUID_Fn80000021_EAX
Bits Feature Description
24 ERAPS:
Indicates support for enhanced return address predictor security.
CPUID_Fn80000021_EBX
Bits Feature Description
31-24 Reserved
23:16 RapSize:
Return Address Predictor size. RapSize x 8 is the minimum number
of CALL instructions software needs to execute to flush the RAP.
15-00 MicrocodePatchSize. Read-only.
Reports the size of the Microcode patch in 16-byte multiples.
If 0, the size of the patch is at most 5568 (15C0h) bytes.
Link: https://www.amd.com/content/dam/amd/en/documents/epyc-technical-docs/programmer-references/57238.zip
Signed-off-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/7c62371fe60af1e9bbd853f5f8e949bf2d908bd0.1729807947.git.babu.moger@amd.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
