Use the correct sctlr for EL2&0 regime. Due to header ordering,
and where arm_mmu_idx_el is declared, we need to move the function
out of line. Use the function in many more places in order to
select the correct control.
Backports commit aaec143212bb70ac9549cf73203d13100bd5c7c2 from qemu
Return the indexes for the EL2&0 regime when the appropriate bits
are set within HCR_EL2.
Backports commit 6003d9800ee38aa11eefb5cd64ae55abb64bef16 from qemu
Create a predicate to indicate whether the regime has
both positive and negative addresses.
Backports commit 339370b90d067345b69585ddf4b668fa01f41d67 from qemu
Prepare for, but do not yet implement, the EL2&0 regime.
This involves adding the new MMUIdx enumerators and adjusting
some of the MMUIdx related predicates to match.
Backports commit b9f6033c1a5fb7da55ed353794db8ec064f78bb2 from qemu.
Replace the magic numbers with the relevant ARM_MMU_IDX_M_* constants.
Keep the definitions short by referencing previous symbols.
Backports commit 25568316b2a7e73d68701042ba6ebdb217205e20 from qemu
Define via macro expansion, so that renumbering of the base ARMMMUIdx
symbols is automatically reflected in the bit definitions.
Backports commit 5f09a6dfbfbff4662f52cc3130a2e07044816497 from qemu
We are about to expand the number of mmuidx to 10, and so need 4 bits.
For the benefit of reading the number out of -d exec, align it to the
penultimate nibble.
Backports commit 506f149815c2168f16ade17893e117419d93f248 from qemu
We had completely run out of TBFLAG bits.
Split A- and M-profile bits into two overlapping buckets.
This results in 4 free bits.
We used to initialize all of the a32 and m32 fields in DisasContext
by assignment, in arm_tr_init_disas_context. Now we only initialize
either the a32 or m32 by assignment, because the bits overlap in
tbflags. So zero the entire structure in gen_intermediate_code.
Backports commit 79cabf1f473ca6e9fa0727f64ed9c2a84a36f0aa from qemu
This is part of a reorganization to the set of mmu_idx.
The non-secure EL2 regime only has a single stage translation;
there is no point in pointing out that the idx is for stage1.
Backports commit e013b7411339342aac8d986c5d5e329e1baee8e1 from qemu
This is part of a reorganization to the set of mmu_idx.
The EL3 regime only has a single stage translation, and
is always secure.
Backports commit 127b2b086303296289099a6fb10bbc51077f1d53 from qemu
This is part of a reorganization to the set of mmu_idx.
This emphasizes that they apply to the Secure EL1&0 regime.
Backports commit fba37aedecb82506c62a1f9e81d066b4fd04e443 from qemu
This is part of a reorganization to the set of mmu_idx.
The EL1&0 regime is the only one that uses 2-stage translation.
Spelling out Stage avoids confusion with Secure.
Backports commit 2859d7b590760283a7b5aef40b723e9dfd7c98ba from qemu
This is part of a reorganization to the set of mmu_idx.
This emphasizes that they apply to the EL1&0 regime.
The ultimate goal is
-- Non-secure regimes:
ARMMMUIdx_E10_0,
ARMMMUIdx_E20_0,
ARMMMUIdx_E10_1,
ARMMMUIdx_E2,
ARMMMUIdx_E20_2,
-- Secure regimes:
ARMMMUIdx_SE10_0,
ARMMMUIdx_SE10_1,
ARMMMUIdx_SE3,
-- Helper mmu_idx for non-secure EL1&0 stage1 and stage2
ARMMMUIdx_Stage2,
ARMMMUIdx_Stage1_E0,
ARMMMUIdx_Stage1_E1,
The 'S' prefix is reserved for "Secure". Unless otherwise specified,
each mmu_idx represents all stages of translation.
Backports commit 01b98b686460b3a0fb47125882e4f8d4268ac1b6 from qemu
At the same time, add writefn to TTBR0_EL2 and TCR_EL2.
A later patch will update any ASID therein.
Backports commit ed30da8eee6906032b38a84e4807e2142b09d8ec from qemu
Not all of the breakpoint types are supported, but those that
only examine contextidr are extended to support the new register.
Backports commit e2a1a4616c86159eb4c07659a02fff8bb25d3729 from qemu
When support for the AHP flag was added we inexplicably only freed the
new temps in one of the two legs. Move those tcg_temp_free to the same
level as the allocation to fix that leak.
Backports commit aeab8e5eb220cc5ff84b0b68b9afccc611bf0fcd from qemu
In the PAC computation, sbox was applied over wrong bits.
As this is a 4-bit sbox, bit index should be incremented by 4 instead of 16.
Test vector from QARMA paper (https://eprint.iacr.org/2016/444.pdf) was
used to verify one computation of the pauth_computepac() function which
uses sbox2.
Launchpad: https://bugs.launchpad.net/bugs/1859713
Backports commit de0b1bae6461f67243282555475f88b2384a1eb9 from qemu
The PMU is not optional on cortex-r5 and cortex-r5f (see
the "Features" chapter of the Technical Reference Manual).
Backports commit 90f671581ac601fcc1b840d9e9abe7e3c3e672db from qemu
During the conversion to decodetree, the setting of
ISSIs16Bit got lost. This causes the guest os to
incorrectly adjust trapping memory operations.
Backports commit 1a1fbc6cbb34c26d43d8360c66c1d21681af14a9 from qemu
The IL bit is set for 32-bit instructions, thus passing false
with the is_16bit parameter to syn_data_abort_with_iss() makes
a syn mask that always has the IL bit set.
Pass is_16bit as true to make the initial syn mask have IL=0,
so that the final IL value comes from or'ing template_syn.
Cc: qemu-stable@nongnu.org
Fixes: aaa1f954d4ca ("target-arm: A64: Create Instruction Syndromes for Data Aborts")
Backports commit 30d544839e278dc76017b9a42990c41e84a34377 from qemu
The wfi instruction can be configured to be trapped by a higher exception
level, such as the EL2 hypervisor. When the instruction is trapped, the
program counter should contain the address of the wfi instruction that
caused the exception. The program counter is adjusted for this in the wfi op
helper function.
However, this correction is done to env->pc, which only applies to AArch64
mode. For AArch32, the program counter is stored in env->regs[15]. This
adds an if-else statement to modify the correct program counter location
based on the the current CPU mode.
Backports commit 855532912b0e1bf803ae393e5b0c7e80948cd6a4 from qemu
The SPSR register is named within the Unicorn headers, but the code
to access it is absent. This means that it will always read as 0 and
ignore writes. This makes it harder to work with changes in processor
mode, as the usual way to return from a CPU exception is a
`MOVS pc, lr` for undefined instructions or `SUBS pc, lr, #4`
for most other aborts - which implicitly restores the CPSR from SPSR.
This change adds the access to the SPSR so that it can be read and
written as the caller might expect.
Backports commit 99097cab4c39fb3fc50eea8f0006954f62a149b2 from unicorn.
Fixes:
target/arm/translate-a64.c: In function 'disas_crypto_three_reg_sha512':
target/arm/translate-a64.c:13625:9: error: 'genfn' may be used uninitialized in this function [-Werror=maybe-uninitialized]
genfn(tcg_rd_ptr, tcg_rn_ptr, tcg_rm_ptr);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
qemu/target/arm/translate-a64.c:13609:8: error: 'feature' may be used uninitialized in this function [-Werror=maybe-uninitialized]
if (!feature) {
Backports commit c7a5e7910517e2711215a9e869a733ffde696091 from qemu
Before we introduce blocking semihosting calls we need to ensure we
can restart the system on semi hosting exception. To be able to do
this the EXCP_SEMIHOST operation should be idempotent until it finally
completes. Practically this means ensureing we only update the pc
after the semihosting call has completed.
Backports commit 4ff5ef9e911c670ca10cdd36dd27c5395ec2c753 from qemu
All semihosting exceptions are dealt with earlier in the common code
so we should never get here.
Backports commit b906acbb3aceed5b1eca30d9d365d5bd7431400b from qemu
A write to the SCR can change the effective EL by droppping the system
from secure to non-secure mode. However if we use a cached current_el
from before the change we'll rebuild the flags incorrectly. To fix
this we introduce the ARM_CP_NEWEL CP flag to indicate the new EL
should be used when recomputing the flags.
Backports partof commit f80741d107673f162e3b097fc76a1590036cc9d1 from
qemu
ARMv8.2 introduced support for Data Cache Clean instructions
to PoP (point-of-persistence) - DC CVAP and PoDP (point-of-deep-persistence)
- DV CVADP. Both specify conceptual points in a memory system where all writes
that are to reach them are considered persistent.
The support provided considers both to be actually the same so there is no
distinction between the two. If none is available (there is no backing store
for given memory) both will result in Data Cache Clean up to the point of
coherency. Otherwise sync for the specified range shall be performed.
Backports commit 0d57b49992200a926c4436eead97ecfc8cc710be from qemu
This change ensures that the FPU can be accessed in Non-Secure mode
when the CPU core is reset using the arm_set_cpu_on() function call.
The NSACR.{CP11,CP10} bits define the exception level required to
access the FPU in Non-Secure mode. Without these bits set, the CPU
will give an undefined exception trap on the first FPU access for the
secondary cores under Linux.
This is necessary because in this power-control codepath QEMU
is effectively emulating a bit of EL3 firmware, and has to set
the CPU up as the EL3 firmware would.
Fixes: fc1120a7f5
Backports commit 0c7f8c43daf6556078e51de98aa13f069e505985 from qemu
QEMU lacks the minimum Jazelle implementation that is required
by the architecture (everything is RAZ or RAZ/WI). Add it
together with the HCR_EL2.TID0 trapping that goes with it.
Backports commit f96f3d5f09973ef40f164cf2d5fd98ce5498b82a from qemu
HSTR_EL2 offers a way to trap ranges of CP15 system register
accesses to EL2, and it looks like this register is completely
ignored by QEMU.
To avoid adding extra .accessfn filters all over the place (which
would have a direct performance impact), let's add a new TB flag
that gets set whenever HSTR_EL2 is non-zero and that QEMU translates
a context where this trap has a chance to apply, and only generate
the extra access check if the hypervisor is actively using this feature.
Tested with a hand-crafted KVM guest accessing CBAR.
Backports commit 5bb0a20b74ad17dee5dae38e3b8b70b383ee7c2d from qemu
HCR_EL2.TID3 requires that AArch32 reads of MVFR[012] are trapped to
EL2, and HCR_EL2.TID0 does the same for reads of FPSID.
In order to handle this, introduce a new TCG helper function that
checks for these control bits before executing the VMRC instruction.
Tested with a hacked-up version of KVM/arm64 that sets the control
bits for 32bit guests.
Backports commit 9ca1d776cb49c09b09579d9edd0447542970c834 from qemu
HCR_EL2.TID1 mandates that access from EL1 to REVIDR_EL1, AIDR_EL1
(and their 32bit equivalents) as well as TCMTR, TLBTR are trapped
to EL2. QEMU ignores it, making it harder for a hypervisor to
virtualize the HW (though to be fair, no known hypervisor actually
cares).
Do the right thing by trapping to EL2 if HCR_EL2.TID1 is set.
Backports commit 93fbc983b29a2eb84e2f6065929caf14f99c3681 from qemu
HCR_EL2.TID2 mandates that access from EL1 to CTR_EL0, CCSIDR_EL1,
CCSIDR2_EL1, CLIDR_EL1, CSSELR_EL1 are trapped to EL2, and QEMU
completely ignores it, making it impossible for hypervisors to
virtualize the cache hierarchy.
Do the right thing by trapping to EL2 if HCR_EL2.TID2 is set.
Backports commit 630fcd4d2ba37050329e0adafdc552d656ebe2f3 from qemu
This is derived from cortex-m4 description, adding DP support and FPv5
instructions with the corresponding flags in isar and mvfr2.
Checked that it could successfully execute
vrinta.f32 s15, s15
while cortex-m4 emulation rejects it with "illegal instruction".
Backports commit cf7beda5072e106ddce875c1996446540c5fe239 from qemu
HCR_EL2.TID3 mandates that access from EL1 to a long list of id
registers traps to EL2, and QEMU has so far ignored this requirement.
This breaks (among other things) KVM guests that have PtrAuth enabled,
while the hypervisor doesn't want to expose the feature to its guest.
To achieve this, KVM traps the ID registers (ID_AA64ISAR1_EL1 in this
case), and masks out the unsupported feature.
QEMU not honoring the trap request means that the guest observes
that the feature is present in the HW, starts using it, and dies
a horrible death when KVM injects an UNDEF, because the feature
*really* isn't supported.
Do the right thing by trapping to EL2 if HCR_EL2.TID3 is set.
Note that this change does not include trapping of the MVFR
registers from AArch32 (they are accessed via the VMRS
instruction and need to be handled in a different way).
Backports commit 6a4ef4e5d1084ce41fafa7d470a644b0fd3d9317 from qemu
The ARMv8 ARM states when executing at EL2, EL3 or Secure EL1,
ISR_EL1 shows the pending status of the physical IRQ, FIQ, or
SError interrupts.
Unfortunately, QEMU's implementation only considers the HCR_EL2
bits, and ignores the current exception level. This means a hypervisor
trying to look at its own interrupt state actually sees the guest
state, which is unexpected and breaks KVM as of Linux 5.3.
Instead, check for the running EL and return the physical bits
if not running in a virtualized context.
Backports commit 7cf95aed53c8770a338617ef40d5f37d2c197853 from qemu
According to the PushStack() pseudocode in the armv7m RM,
bit 4 of the LR should be set to NOT(CONTROL.PFCA) when
an FPU is present. Current implementation is doing it for
armv8, but not for armv7. This patch makes the existing
logic applicable to both code paths.
Backports commit f900b1e5b087a02199fbb6de7038828008e9e419 from qemu
Simply moving the non-stub helper_v7m_mrs/msr outside of
!CONFIG_USER_ONLY is not an option, because of all of the
other system-mode helpers that are called.
But we can split out a few subroutines to handle the few
EL0 accessible registers without duplicating code.
Backports commit 04c9c81b8fa2ee33f59a26265700fae6fc646062 from qemu
There was too much cut and paste between ldrexd and strexd,
as ldrexd does prohibit two output registers the same.
Fixes: af288228995
Backports commit 655b02646dc175dc10666459b0a1e4346fc8d46a from qemu
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.
Backports commit 14776ab5a12972ea439c7fb2203a4c15a09094b4 from qemu
There are only two remaining uses of gen_bx_im. In each case, we
know the destination mode -- not changing in the case of gen_jmp
or changing in the case of trans_BLX_i. Use this to simplify the
surrounding code.
For trans_BLX_i, use gen_jmp for the actual branch. For gen_jmp,
use gen_set_pc_im to set up the single-step.
Backports commit eac2f39602e0423adf56be410c9a22c31fec9a81 from qemu
Now that all callers pass a constant value, split the switch
statement into the individual trans_* functions.
Backports commit 279de61a21a1622cb875ead82d6e78c989ba2966 from qemu
Add a check for ARMv6 in trans_CPS. We had this correct in
the T16 path, but had previously forgotten the check on the
A32 and T32 paths.
Backports commit 20556e7bd6111266fbf1d81e4ff7a89bfa5795a7 from qemu
Fold away all of the cases that now just goto illegal_op,
because all of their internal bits are now in decodetree.
Backports commit 590057d969a54de5d97261701c5702b3bebc9c07 from qemu
Fold away all of the cases that now just goto illegal_op,
because all of their internal bits are now in decodetree.
Backports commit f843e77144c9334e244a422848177f2fbef5eb05 from qemu
We have been using store_reg and not store_reg_for_load when writing
back a loaded value into the base register. At first glance this is
incorrect when base == pc, however that case is UNPREDICTABLE.
Backports commit b0e382b8cf365fed8b8c43482029ac7655961a85 from qemu
This has been a TODO item for quite a while. The minimum bit
count for A32 and T16 is 1, and for T32 is 2.
Backports commit 4b222545dbf30b60c033e1cd6eddda612575fd8c from qemu
Prior to v7, for the A32 encoding, this operation wrote an UNKNOWN
value back to the base register. Starting in v7 this is UNPREDICTABLE.
Backports commit 3949f4675d13c587078f8f423845a3a537a22595 from qemu
This includes a minor bug fix to LDM (user), which requires
bit 21 to be 0, which means no writeback.
Backports commit c5c426d4c680f908a1e262091a17b088b5709200 from qemu
In op_bfx, note that tcg_gen_{,s}extract_i32 already checks
for width == 32, so we don't need to special case that here.
Backports commit 86d21e4b509a2835ed79f234f476a4c5191d435b from qemu
Pass the T5 encoding of SUBS PC, LR, #IMM through the normal SUBS path
to make it clear exactly what's happening -- we hit ALUExceptionReturn
along that path.
Backports commit ef11bc3c461e2c650e8bef552146a4b08f81884e from qemu
Document our choice about the T32 CONSTRAINED UNPREDICTABLE behaviour.
This matches the undocumented choice made by the legacy decoder.
Backports commit 4c97f5b2f0fa9b37f9ff497f15411d809e6fd098 from qemu
The m-profile and a-profile decodings overlap. Only return false
for the case of wrong profile; handle UNDEFINED for permission failure
directly. This ensures that we don't accidentally pass an insn that
applies to the wrong profile.
Backports commit d0b26644502103ca97093ef67749812dc1df7eea from qemu
By shifting the 16-bit input left by 16, we can align the desired
portion of the 48-bit product and use tcg_gen_muls2_i32.
Backports commit 485b607d4f393e0de92c922806a68aef22340c98 from qemu
Since all of the inputs and outputs are i32, dispense with
the intermediate promotion to i64 and use tcg_gen_add2_i32.
Backports commit ea96b374641bc429269096d88d4e91ee544273e9 from qemu
Since all of the inputs and outputs are i32, dispense with
the intermediate promotion to i64 and use tcg_gen_mulu2_i32
and tcg_gen_add2_i32.
Backports commit 2409d56454f0d028619fb1002eda86bf240906dd from qemu
Convert the modified immediate form of the data processing insns.
For A32, we can finally remove any code that was intertwined with
the register and register-shifted-register forms.
Backports commit 581c6ebd17c8f56ad52772216e6c6d8cc8997e8b from qemu
Convert the register shifted by register form of the data
processing insns. For A32, we cannot yet remove any code
because the legacy decoder intertwines the immediate form.
Backports commit 5be2c12337f4cbdbda4efe6ab485350f730faaad from qemu
Convert the register shifted by immediate form of the data
processing insns. For A32, we cannot yet remove any code
because the legacy decoder intertwines the reg-shifted-reg
and immediate forms.
Backports commit 25ae32c558182c07fc6ad01b936e9151cbf00c44 from qemu
Add the infrastructure that will become the new decoder.
No instructions adjusted so far.
Backports commit 51409b9e8cfe997b1ac3365df7400e0c6e844437 from qemu
This function already includes the test for an interworking write
to PC from a load. Change the T32 LDM implementation to match the
A32 LDM implementation.
For LDM, the reordering of the tests does not change valid
behaviour because the only case that differs is has rn == 15,
which is UNPREDICTABLE.
Backports commit 69be3e13764111737e1a7a13bb0c231e4d5be756 from qemu
The previous simplification got the order of operands to the
subtraction wrong. Since the 64-bit product is the subtrahend,
we must use a 64-bit subtract to properly compute the borrow
from the low-part of the product.
Fixes: 5f8cd06ebcf5 ("target/arm: Simplify SMMLA, SMMLAR, SMMLS, SMMLSR")
Backports commit e0a0c8322b8ebcdad674f443a3e86db8708d6738 from qemu
The translation table walk for an ATS instruction can result in
various faults. In general these are just reported back via the
PAR_EL1 fault status fields, but in some cases the architecture
requires that the fault is turned into an exception:
* synchronous stage 2 faults of any kind during AT S1E0* and
AT S1E1* instructions executed from NS EL1 fault to EL2 or EL3
* synchronous external aborts are taken as Data Abort exceptions
(This is documented in the v8A Arm ARM DDI0487A.e D5.2.11 and
G5.13.4.)
Backports commit 0710b2fa84a4aeb925422e1e88edac49ed407c79 from qemu
Currently the only part of an ARMCPRegInfo which is allowed to cause
a CPU exception is the access function, which returns a value indicating
that some flavour of UNDEF should be generated.
For the ATS system instructions, we would like to conditionally
generate exceptions as part of the writefn, because some faults
during the page table walk (like external aborts) should cause
an exception to be raised rather than returning a value.
There are several ways we could do this:
* plumb the GETPC() value from the top level set_cp_reg/get_cp_reg
helper functions through into the readfn and writefn hooks
* add extra readfn_with_ra/writefn_with_ra hooks that take the GETPC()
value
* require the ATS instructions to provide a dummy accessfn,
which serves no purpose except to cause the code generation
to emit TCG ops to sync the CPU state
* add an ARM_CP_ flag to mark the ARMCPRegInfo as possibly
throwing an exception in its read/write hooks, and make the
codegen sync the CPU state before calling the hooks if the
flag is set
This patch opts for the last of these, as it is fairly simple
to implement and doesn't require invasive changes like updating
the readfn/writefn hook function prototype signature.
Backports commit 37ff584c15bc3e1dd2c26b1998f00ff87189538c from qemu
Make this a static function private to translate.c.
Thus we can use the same idiom between aarch64 and aarch32
without actually sharing function implementations.
Backports commit 1ce21ba1eaf08b22da5925f3e37fc0b4322da858 from qemu
Despite the fact that the text for the call to gen_exception_insn
is identical for aarch64 and aarch32, the implementation inside
gen_exception_insn is totally different.
This fixes exceptions raised from aarch64.
This reverts commit fb2d3c9a9a.
Separate shift + extract low will result in one extra insn
for hosts like RISC-V, MIPS, and Sparc.
Backports commit 664b7e3b97d6376f3329986c465b3782458b0f8b from qemu
All of the inputs to these instructions are 32-bits. Rather than
extend each input to 64-bits and then extract the high 32-bits of
the output, use tcg_gen_muls2_i32 and other 32-bit generator functions.
Backports commit 5f8cd06ebcf57420be8fea4574de2e074de46709 from qemu
Rotate is the more compact and obvious way to swap 16-bit
elements of a 32-bit word.
Backports commit adefba76e8bf10dfb342094d2f5debfeedb1a74d from qemu
The helper function is more documentary, and also already
handles the case of rotate by zero.
Backports commit dd861b3f29be97a9e3cdb9769dcbc0c7d7825185 from qemu
The immediate shift generator functions already test for,
and eliminate, the case of a shift by zero.
Backports commit 464eaa9571fae5867d9aea7d7209c091c8a50223 from qemu
Unless we're guaranteed to always increase ARM_MAX_VQ by a multiple of
four, then we should use DIV_ROUND_UP to ensure we get an appropriate
array size.
Backports commit 46417784d21c89446763f2047228977bdc267895 from qemu
The current implementation of ZCR_ELx matches the architecture, only
implementing the lower four bits, with the rest RAZ/WI. This puts
a strict limit on ARM_MAX_VQ of 16. Make sure we don't let ARM_MAX_VQ
grow without a corresponding update here.
Backports commit 7b351d98709d3f77d6bb18562e1bf228862b0d57 from qemu
Replace x = double_saturate(y) with x = add_saturate(y, y).
There is no need for a separate more specialized helper.
Backports commit 640581a06d14e2d0d3c3ba79b916de6bc43578b0 from qemu
Promote this function from aarch64 to fully general use.
Use it to unify the code sequences for generating illegal
opcode exceptions.
Backports commit 3cb36637157088892e9e33ddb1034bffd1251d3b from qemu
Unlike the other more generic gen_exception{,_internal}_insn
interfaces, breakpoints always refer to the current instruction.
Backports commit 06bcbda3f64d464b6ecac789bce4bd69f199cd68 from qemu
The offset is variable depending on the instruction set.
Passing in the actual value is clearer in intent.
Backpors commit aee828e7541a5895669ade3a4b6978382b6b094a from qemu
We must update s->base.pc_next when we return from the translate_insn
hook to the main translator loop. By incrementing s->base.pc_next
immediately after reading the insn word, "pc_next" contains the address
of the next instruction throughout translation.
All remaining uses of s->pc are referencing the address of the next insn,
so this is now a simple global replacement. Remove the "s->pc" field.
Backports commit a04159166b880b505ccadc16f2fe84169806883d from qemu
Provide a common routine for the places that require ALIGN(PC, 4)
as the base address as opposed to plain PC. The two are always
the same for A32, but the difference is meaningful for thumb mode.
Backports commit 16e0d8234ef9291747332d2c431e46808a060472 from qemu
We currently have 3 different ways of computing the architectural
value of "PC" as seen in the ARM ARM.
The value of s->pc has been incremented past the current insn,
but that is all. Thus for a32, PC = s->pc + 4; for t32, PC = s->pc;
for t16, PC = s->pc + 2. These differing computations make it
impossible at present to unify the various code paths.
With the newly introduced s->pc_curr, we can compute the correct
value for all cases, using the formula given in the ARM ARM.
This changes the behaviour for load_reg() and load_reg_var()
when called with reg==15 from a 32-bit Thumb instruction:
previously they would have returned the incorrect value
of pc_curr + 6, and now they will return the architecturally
correct value of PC, which is pc_curr + 4. This will not
affect well-behaved guest software, because all of the places
we call these functions from T32 code are instructions where
using r15 is UNPREDICTABLE. Using the architectural PC value
here is more consistent with the T16 and A32 behaviour.
Backports commit fdbcf6329d0c2984c55d7019419a72bf8e583c36 from qemu
Add a new field to retain the address of the instruction currently
being translated. The 32-bit uses are all within subroutines used
by a32 and t32. This will become less obvious when t16 support is
merged with a32+t32, and having a clear definition will help.
Convert aarch64 as well for consistency. Note that there is one
instance of a pre-assert fprintf that used the wrong value for the
address of the current instruction.
Backports commit 43722a6d4f0c92f7e7e1e291580039b0f9789df1 from qemu
This function is used in two different contexts, and it will be
clearer if the function is given the address to which it applies.
Backports commit 331b1ca616cb708db30dab68e3262d286e687f24 from qemu
When generating an architectural single-step exception we were
routing it to the "default exception level", which is to say
the same exception level we execute at except that EL0 exceptions
go to EL1. This is incorrect because the debug exception level
can be configured by the guest for situations such as single
stepping of EL0 and EL1 code by EL2.
We have to track the target debug exception level in the TB
flags, because it is dependent on CPU state like HCR_EL2.TGE
and MDCR_EL2.TDE. (That we were previously calling the
arm_debug_target_el() function to determine dc->ss_same_el
is itself a bug, though one that would only have manifested
as incorrect syndrome information.) Since we are out of TB
flag bits unless we want to expand into the cs_base field,
we share some bits with the M-profile only HANDLER and
STACKCHECK bits, since only A-profile has this singlestep.
Fixes: https://bugs.launchpad.net/qemu/+bug/1838913
Backports commit 8bd587c1066f4456ddfe611b571d9439a947d74c from qemu
Factor out code to 'generate a singlestep exception', which is
currently repeated in four places.
To do this we need to also pull the identical copies of the
gen-exception() function out of translate-a64.c and translate.c
into translate.h.
(There is a bug in the code: we're taking the exception to the wrong
target EL. This will be simpler to fix if there's only one place to
do it.)
Backports commit c1d5f50f094ab204accfacc2ee6aafc9601dd5c4 from qemu
While most features are now detected by probing the ID_* registers
kernels can (and do) use MIDR_EL1 for working out of they have to
apply errata. This can trip up warnings in the kernel as it tries to
work out if it should apply workarounds to features that don't
actually exist in the reported CPU type.
Avoid this problem by synthesising our own MIDR value.
Backports commit 2bd5f41c00686a1f847a60824d0375f3df2c26bf from qemu
rt==15 is a special case when reading the flags: it means the
destination is APSR. This patch avoids rejecting vmrs apsr_nzcv, fpscr
as illegal instruction.
Backports commit cdc6896659b85f7ed8f7552850312e55170de0c5 from qemu
An attempt to do an exception-return (branch to one of the magic
addresses) in linux-user mode for M-profile should behave like
a normal branch, because linux-user mode is always going to be
in 'handler' mode. This used to work, but we broke it when we added
support for the M-profile security extension in commit d02a8698d7ae2bfed.
In that commit we allowed even handler-mode calls to magic return
values to be checked for and dealt with by causing an
EXCP_EXCEPTION_EXIT exception to be taken, because this is
needed for the FNC_RETURN return-from-non-secure-function-call
handling. For system mode we added a check in do_v7m_exception_exit()
to make any spurious calls from Handler mode behave correctly, but
forgot that linux-user mode would also be affected.
How an attempted return-from-non-secure-function-call in linux-user
mode should be handled is not clear -- on real hardware it would
result in return to secure code (not to the Linux kernel) which
could then handle the error in any way it chose. For QEMU we take
the simple approach of treating this erroneous return the same way
it would be handled on a CPU without the security extensions --
treat it as a normal branch.
The upshot of all this is that for linux-user mode we should never
do any of the bx_excret magic, so the code change is simple.
This ought to be a weird corner case that only affects broken guest
code (because Linux user processes should never be attempting to do
exception returns or NS function returns), except that the code that
assigns addresses in RAM for the process and stack in our linux-user
code does not attempt to avoid this magic address range, so
legitimate code attempting to return to a trampoline routine on the
stack can fall into this case. This change fixes those programs,
but we should also look at restricting the range of memory we
use for M-profile linux-user guests to the area that would be
real RAM in hardware.
Backports commit 9027d3fba605d8f6093342ebe4a1da450d374630 from qemu
The function neon_store_reg32() doesn't free the TCG temp that it
is passed, so the caller must do that. We got this right in most
places but forgot to free the TCG temps in trans_VMOV_64_sp().
Backports commit 38fb634853ac6547326d9f88b9a068d9fc6b4ad4 from qemu
In Arm v8.0 M-profile CPUs without the Security Extension and also in
v7M CPUs, there is no NSACR register. However, the code we have to handle
the FPU does not always check whether the ARM_FEATURE_M_SECURITY bit
is set before testing whether env->v7m.nsacr permits access to the
FPU. This means that for a CPU with an FPU but without the Security
Extension we would always take a bogus fault when trying to stack
the FPU registers on an exception entry.
We could fix this by adding extra feature bit checks for all uses,
but it is simpler to just make the internal value of nsacr 0xcff
("all non-secure accesses allowed"), since this is not guest
visible when the Security Extension is not present. This allows
us to continue to follow the Arm ARM pseudocode which takes a
similar approach. (In particular, in the v8.1 Arm ARM the register
is documented as reading as 0xcff in this configuration.)
Fixes: https://bugs.launchpad.net/qemu/+bug/1838475
Backports commit 02ac2f7f613b47f6a5b397b20ab0e6b2e7fb89fa from qemu
Most Arm architectural debug exceptions (eg watchpoints) are ignored
if the configured "debug exception level" is below the current
exception level (so for example EL1 can't arrange to get debug exceptions
for EL2 execution). Exceptions generated by the BRK or BPKT instructions
are a special case -- they must always cause an exception, so if
we're executing above the debug exception level then we
must take them to the current exception level.
This fixes a bug where executing BRK at EL2 could result in an
exception being taken at EL1 (which is strictly forbidden by the
architecture).
Fixes: https://bugs.launchpad.net/qemu/+bug/1838277
Backports commit 987a23224218fa3bb3aa0024ad236dcf29ebde9e from qemu
In arm_cpu_realizefn() we make several assertions about the values of
guest ID registers:
* if the CPU provides AArch32 v7VE or better it must advertise the
ARM_DIV feature
* if the CPU provides AArch32 A-profile v6 or better it must
advertise the Jazelle feature
These are essentially consistency checks that our ID register
specifications in cpu.c didn't accidentally miss out a feature,
because increasingly the TCG emulation gates features on the values
in ID registers rather than using old-style checks of ARM_FEATURE_FOO
bits.
Unfortunately, these asserts can cause problems if we're running KVM,
because in that case we don't control the values of the ID registers
-- we read them from the host kernel. In particular, if the host
kernel is older than 4.15 then it doesn't expose the ID registers via
the KVM_GET_ONE_REG ioctl, and we set up dummy values for some
registers and leave the rest at zero. (See the comment in
target/arm/kvm64.c kvm_arm_get_host_cpu_features().) This set of
dummy values is not sufficient to pass our assertions, and so on
those kernels running an AArch32 guest on AArch64 will assert.
We could provide a more sophisticated set of dummy ID registers in
this case, but that still leaves the possibility of a host CPU which
reports bogus ID register values that would cause us to assert. It's
more robust to only do these ID register checks if we're using TCG,
as that is the only case where this is truly a QEMU code bug.
Backports commit 8f4821d77e465bc2ef77302d47640d5a43d92b30 from qemu
Reported by GCC9 when building with -Wimplicit-fallthrough=2:
target/arm/helper.c: In function ‘arm_cpu_do_interrupt_aarch32_hyp’:
target/arm/helper.c:7958:14: error: this statement may fall through [-Werror=implicit-fallthrough=]
7958 | addr = 0x14;
| ~~~~~^~~~~~
target/arm/helper.c:7959:5: note: here
7959 | default:
| ^~~~~~~
cc1: all warnings being treated as errors
Backports commit 9bbb4ef991fa93323f87769a6e217c2b9273a128 from qemu
In the M-profile architecture, when we do a vector table fetch and it
fails, we need to report a HardFault. Whether this is a Secure HF or
a NonSecure HF depends on several things. If AIRCR.BFHFNMINS is 0
then HF is always Secure, because there is no NonSecure HardFault.
Otherwise, the answer depends on whether the 'underlying exception'
(MemManage, BusFault, SecureFault) targets Secure or NonSecure. (In
the pseudocode, this is handled in the Vector() function: the final
exc.isSecure is calculated by looking at the exc.isSecure from the
exception returned from the memory access, not the isSecure input
argument.)
We weren't doing this correctly, because we were looking at
the target security domain of the exception we were trying to
load the vector table entry for. This produces errors of two kinds:
* a load from the NS vector table which hits the "NS access
to S memory" SecureFault should end up as a Secure HardFault,
but we were raising an NS HardFault
* a load from the S vector table which causes a BusFault
should raise an NS HardFault if BFHFNMINS == 1 (because
in that case all BusFaults are NonSecure), but we were raising
a Secure HardFault
Correct the logic.
We also fix a comment error where we claimed that we might
be escalating MemManage to HardFault, and forgot about SecureFault.
(Vector loads can never hit MPU access faults, because they're
always aligned and always use the default address map.)
Backports commit 51c9122e92b776a3f16af0b9282f1dc5012e2a19 from qemu
The ARMv5 architecture didn't specify detailed per-feature ID
registers. Now that we're using the MVFR0 register fields to
gate the existence of VFP instructions, we need to set up
the correct values in the cpu->isar structure so that we still
provide an FPU to the guest.
This fixes a regression in the arm926 and arm1026 CPUs, which
are the only ones that both have VFP and are ARMv5 or earlier.
This regression was introduced by the VFP refactoring, and more
specifically by commits 1120827fa182f0e76 and 266bd25c485597c,
which accidentally disabled VFP short-vector support and
double-precision support on these CPUs.
Backports commit cb7cef8b32033f6284a47d797edd5c19c5491698 from qemu
When we converted to using feature bits in 602f6e42cfbf we missed out
the fact (dp && arm_dc_feature(s, ARM_FEATURE_V8)) was supported for
-cpu max configurations. This caused a regression in the GCC test
suite. Fix this by setting the appropriate bits in mvfr1.FPHP to
report ARMv8-A with FP support (but not ARMv8.2-FP16).
Fixes: https://bugs.launchpad.net/qemu/+bug/1836078
Backports commit 45b1a243b81a7c9ae56235937280711dd9914ca7 from qemu
In commit e9d652824b0 we extracted the vfp_set_fpscr_to_host()
function but failed at calling it in the correct place, we call
it after xregs[ARM_VFP_FPSCR] is modified.
Fix by calling this function before we update FPSCR.
Backports commit 85795187f416326f87177cabc39fae1911f04c50 from qemu
Off by one error in the EL2 and EL3 tests. Remove the test
against EL3 entirely, since it must always be true.
Backports commit 6a02a73211c5bc634fccd652777230954b83ccba from qemu
Coverity points out (CID 1402195) that the loop in trans_VMOV_imm_dp()
that iterates over the destination registers in a short-vector VMOV
accidentally throws away the returned updated register number
from vfp_advance_dreg(). Add the missing assignment. (We got this
correct in trans_VMOV_imm_sp().)
Backports commit 89a11ff756410aecb87d2c774df6e45dbf4105c1 from qemu
Thumb instructions in an IT block are set up to be conditionally
executed depending on a set of condition bits encoded into the IT
bits of the CPSR/XPSR. The architecture specifies that if the
condition bits are 0b1111 this means "always execute" (like 0b1110),
not "never execute"; we were treating it as "never execute". (See
the ConditionHolds() pseudocode in both the A-profile and M-profile
Arm ARM.)
This is a bit of an obscure corner case, because the only legal
way to get to an 0b1111 set of condbits is to do an exception
return which sets the XPSR/CPSR up that way. An IT instruction
which encodes a condition sequence that would include an 0b1111 is
UNPREDICTABLE, and for v8A the CONSTRAINED UNPREDICTABLE choices
for such an IT insn are to NOP, UNDEF, or treat 0b1111 like 0b1110.
Add a comment noting that we take the latter option.
Backports commit 5529de1e5512c05276825fa8b922147663fd6eac from qemu
In the various helper functions for v7M/v8M instructions, use
the _ra versions of cpu_stl_data() and friends. Otherwise we
may get wrong behaviour or an assert() due to not being able
to locate the TB if there is an exception on the memory access
or if it performs an IO operation when in icount mode
Backports commit 2884fbb60412049ec92389039ae716b32057382e from qemu
In preparation for supporting TCG disablement on ARM, we move most
of TCG related v7m/v8m helpers and APIs into their own file.
Note: It is easier to review this commit using the 'histogram'
diff algorithm:
$ git diff --diff-algorithm=histogram ...
or
$ git diff --histogram ...
Backports commit 7aab5a8c8bb525ea390b4ebc17ab82c0835cfdb6 from qemu
Semihosting hooks either SVC or HLT instructions, and inside KVM
both of those go to EL1, ie to the guest, and can't be trapped to
KVM.
Let check_for_semihosting() return False when not running on TCG.
backports commit 91f78c58da9ba78c8ed00f5d822b701765be8499 from qemu
In the next commit we will split the M-profile functions from this
file. Some function will be called out of helper.c. Declare them in
the "internals.h" header.
Backports commit 787a7e76c2e93a48c47b324fea592c9910a70483 from qemu
This code is specific to the SoftFloat floating-point
implementation, which is only used by TCG.
Backports commit 4a15527c9feecfd2fa2807d5e698abbc19feb35f from qemu
The vfp_set_fpscr() helper contains code specific to the host
floating point implementation (here the SoftFloat library).
Extract this code to vfp_set_fpscr_from_host().
Backports commit 0c6ad94809b37a1f0f1f75d3cd0e4a24fb77e65c from qemu
The vfp_set_fpscr() helper contains code specific to the host
floating point implementation (here the SoftFloat library).
Extract this code to vfp_set_fpscr_to_host().
Backports commit e9d652824b05845f143ef4797d707fae47d4b3ed from qemu
To ease the review of the next commit,
move the vfp_exceptbits_to_host() function directly after
vfp_exceptbits_from_host(). Amusingly the diff shows we
are moving vfp_get_fpscr().
Backports commit 20e62dd8c831c9065ed4a8e64813c93ad61c50d7 from qemu.
These routines are TCG specific.
The arm_deliver_fault() function is only used within the new
helper. Make it static.
Backports commit e21b551cb652663f2f2405a64d63ef6b4a1042b7 from qemu
In the next commit we will split the TLB related routines of
this file, and this function will also be called in the new
file. Declare it in the "internals.h" header.
Backports commit ebae861fc6c385a7bcac72dde4716be06e6776f1 from qemu
Those helpers are a software implementation of the ARM v8 memory zeroing
op code. They should be moved to the op helper file, which is going to
eventually be built only when TCG is enabled.
Backports commit 6cdca173ef81a9dbcee9e142f1a5a34ad9c44b75 from qemu
Since commit 8c06fbdf36b checkpatch.pl enforce a new multiline
comment syntax. Since we'll move this code around, fix its style
first.
Backports commit 9a223097e44d5320f5e0546710263f22d11f12fc from qemu
Group ARM objects together, TCG related ones at the bottom.
This will help when restricting TCG-only objects.
Backports commit 07774d584267488c8c2f104ae5b552791961908a from qemu
Group Aarch64 rules together, TCG related ones at the bottom.
This will help when restricting TCG-only objects.
Backports commit 87f4f183484dba7a460c59e99dac0dbb9f42ed87 from qemu
In commit 1120827fa182f0e7622 we accidentally put the
"UNDEF unless FPU has double-precision support" check in
the single-precision VFM function. Put it in the dp
function where it belongs.
Backports commit 34bea4edb9bbe8edf4b8606276482acdff5ca58b from qemu
The architecture permits FPUs which have only single-precision
support, not double-precision; Cortex-M4 and Cortex-M33 are
both like that. Add the necessary checks on the MVFR0 FPDP
field so that we UNDEF any double-precision instructions on
CPUs like this.
Note that even if FPDP==0 the insns like VMOV-to/from-gpreg,
VLDM/VSTM, VLDR/VSTR which take double precision registers
still exist.
Backports commit 1120827fa182f0e76226df7ffe7a86598d1df54f from qemu
In several places cut and paste errors meant we were using the wrong
type for the 'arg' struct in trans_ functions called by the
decodetree decoder, because we were using the _sp version of the
struct in the _dp function. These were harmless, because the two
structs were identical and so decodetree made them typedefs of the
same underlying structure (and we'd have had a compile error if they
were not harmless), but we should clean them up anyway.
Backports commit 83655223ac6143a563e981906ce13fd6f2cfbefd from qemu
Remove the now unused TCG globals cpu_F0s, cpu_F0d, cpu_F1s, cpu_F1d.
cpu_M0 is still used by the iwmmxt code, and cpu_V0 and
cpu_V1 are used by both iwmmxt and Neon.
Backports commit d9eea52c67c04c58ecceba6ffe5a93d1d02051fa from qemu
Remove some old constructns from NEON_2RM_VCVT_F16_F32 code:
* don't use CPU_F0s
* don't use tcg_gen_st_f32
Backports commit b66f6b9981004bbf120b8d17c20f92785179bdf2 from qemu
Remove some old constructs from NEON_2RM_VCVT_F16_F32 code:
* don't use cpu_F0s
* don't use tcg_gen_ld_f32
Backports commit 58f2682eee738e8890f9cfe858e0f4f68b00d45d from qemu
Stop using cpu_F0s for the Neon f32/s32 VCVT operations.
Since this is the last user of cpu_F0s in the Neon 2rm-op
loop, we can remove the handling code for it too.
Backports commit 60737ed5785b9c1c6f1c85575dfdd1e9eec91878 from qemu
Where Neon instructions are floating point operations, we
mostly use the old VFP utility functions like gen_vfp_abs()
which work on the TCG globals cpu_F0s and cpu_F1s. The
Neon for-each-element loop conditionally loads the inputs
into either a plain old TCG temporary for most operations
or into cpu_F0s for float operations, and similarly stores
back either cpu_F0s or the temporary.
Switch NEON_2RM_VABS_F away from using cpu_F0s, and
update neon_2rm_is_float_op() accordingly.
Backports commit fd8a68cdcf81d70eebf866a132e9780d4108da9c from qemu
The AArch32 VMOV (immediate) instruction uses the same VFP encoded
immediate format we already handle in vfp_expand_imm(). Use that
function rather than hand-decoding it.
Backports commit 9bee50b498410ed6466018b26464d7384c7879e9 from qemu
We want to use vfp_expand_imm() in the AArch32 VFP decode;
move it from the a64-only header/source file to the
AArch32 one (which is always compiled even for AArch64).
Backports commit d6a092d479333b5f20a647a912a31b0102d37335 from qemu
For VFP short vectors, the VFP registers are divided into a
series of banks: for single-precision these are s0-s7, s8-s15,
s16-s23 and s24-s31; for double-precision they are d0-d3,
d4-d7, ... d28-d31. Some banks are "scalar" meaning that
use of a register within them triggers a pure-scalar or
mixed vector-scalar operation rather than a full vector
operation. The scalar banks are s0-s7, d0-d3 and d16-d19.
When using a bank as part of a vector operation, we
iterate through it, increasing the register number by
the specified stride each time, and wrapping around to
the beginning of the bank.
Unfortunately our calculation of the "increment" part of this
was incorrect:
vd = ((vd + delta_d) & (bank_mask - 1)) | (vd & bank_mask)
will only do the intended thing if bank_mask has exactly
one set high bit. For instance for doubles (bank_mask = 0xc),
if we start with vd = 6 and delta_d = 2 then vd is updated
to 12 rather than the intended 4.
This only causes problems in the unlikely case that the
starting register is not the first in its bank: if the
register number doesn't have to wrap around then the
expression happens to give the right answer.
Fix this bug by abstracting out the "check whether register
is in a scalar bank" and "advance register within bank"
operations to utility functions which use the right
bit masking operations
Backports commit 18cf951af9a27ae573a6fa17f9d0c103f7b7679b from qemu
Convert the float-to-integer VCVT instructions to decodetree.
Since these are the last unconverted instructions, we can
delete the old decoder structure entirely now.
Backports commit 3111bfc2da6ba0c8396dc97ca479942d711c6146 from qemu
Convert the VCVT (between floating-point and fixed-point) instructions
to decodetree.
Backports commit e3d6f4290c788e850c64815f0b3e331600a4bcc0 from qemu
Convert the VFP round-to-integer instructions VRINTR, VRINTZ and
VRINTX to decodetree.
These instructions were only introduced as part of the "VFP misc"
additions in v8A, so we check this. The old decoder's implementation
was incorrectly providing them even for v7A CPUs.
Backports commit e25155f55dc4abb427a88dfe58bbbc550fe7d643 from qemu
Convert the VCVTT and VCVTB instructions which convert from
f32 and f64 to f16 to decodetree.
Since we're no longer constrained to the old decoder's style
using cpu_F0s and cpu_F0d we can perform a direct 16 bit
store of the right half of the input single-precision register
rather than doing a load/modify/store sequence on the full
32 bits.
Backports commit cdfd14e86ab0b1ca29a702d13a8e4af2e902a9bf from qemu
Convert the VCVTT, VCVTB instructions that deal with conversion
from half-precision floats to f32 or 64 to decodetree.
Since we're no longer constrained to the old decoder's style
using cpu_F0s and cpu_F0d we can perform a direct 16 bit
load of the right half of the input single-precision register
rather than loading the full 32 bits and then doing a
separate shift or sign-extension.
Backports commit b623d803dda805f07aadcbf098961fde27315c19 from qemu
Convert the VFP comparison instructions to decodetree.
Note that comparison instructions should not honour the VFP
short-vector length and stride information: they are scalar-only
operations. This applies to all the 2-operand instructions except
for VMOV, VABS, VNEG and VSQRT. (In the old decoder this is
implemented via the "if (op == 15 && rn > 3) { veclen = 0; }" check.)
Backports commit 386bba2368842fc74388a3c1651c6c0c0c70adbd from qemu
Convert the VFP VABS instruction to decodetree.
Unlike the 3-op versions, we don't pass fpst to the VFPGen2OpSPFn or
VFPGen2OpDPFn because none of the operations which use this format
and support short vectors will need it.
Backports commit 90287e22c987e9840704345ed33d237cbe759dd9 from qemu
Convert the VFP fused multiply-add instructions (VFNMA, VFNMS,
VFMA, VFMS) to decodetree.
Note that in the old decode structure we were implementing
these to honour the VFP vector stride/length. These instructions
were introduced in VFPv4, and in the v7A architecture they
are UNPREDICTABLE if the vector stride or length are non-zero.
In v8A they must UNDEF if stride or length are non-zero, like
all VFP instructions; we choose to UNDEF always.
Backports commit d4893b01d23060845ee3855bc96626e16aad9ab5 from qemu
Convert the VFP VMLA instruction to decodetree.
This is the first of the VFP 3-operand data processing instructions,
so we include in this patch the code which loops over the elements
for an old-style VFP vector operation. The existing code to do this
looping uses the deprecated cpu_F0s/F0d/F1s/F1d TCG globals; since
we are going to be converting instructions one at a time anyway
we can take the opportunity to make the new loop use TCG temporaries,
which means we can do that conversion one operation at a time
rather than needing to do it all in one go.
We include an UNDEF check which was missing in the old code:
short-vector operations (with stride or length non-zero) were
deprecated in v7A and must UNDEF in v8A, so if the MVFR0 FPShVec
field does not indicate that support for short vectors is present
we UNDEF the operations that would use them. (This is a change
of behaviour for Cortex-A7, Cortex-A15 and the v8 CPUs, which
previously were all incorrectly allowing short-vector operations.)
Note that the conversion fixes a bug in the old code for the
case of VFP short-vector "mixed scalar/vector operations". These
happen where the destination register is in a vector bank but
but the second operand is in a scalar bank. For example
vmla.f64 d10, d1, d16 with length 2 stride 2
is equivalent to the pair of scalar operations
vmla.f64 d10, d1, d16
vmla.f64 d8, d3, d16
where the destination and first input register cycle through
their vector but the second input is scalar (d16). In the
old decoder the gen_vfp_F1_mul() operation uses cpu_F1{s,d}
as a temporary output for the multiply, which trashes the
second input operand. For the fully-scalar case (where we
never do a second iteration) and the fully-vector case
(where the loop loads the new second input operand) this
doesn't matter, but for the mixed scalar/vector case we
will end up using the wrong value for later loop iterations.
In the new code we use TCG temporaries and so avoid the bug.
This bug is present for all the multiply-accumulate insns
that operate on short vectors: VMLA, VMLS, VNMLA, VNMLS.
Note 2: the expression used to calculate the next register
number in the vector bank is not in fact correct; we leave
this behaviour unchanged from the old decoder and will
fix this bug later in the series.
Backports commit 266bd25c485597c94209bfdb3891c1d0c573c164 from qemu
Expand out the sequences in the new decoder VLDR/VSTR/VLDM/VSTM trans
functions which perform the memory accesses by going via the TCG
globals cpu_F0s and cpu_F0d, to use local TCG temps instead.
Backports commit 3993d0407dff7233e42f2251db971e126a0497e9 from qemu
Convert the VFP load/store multiple insns to decodetree.
This includes tightening up the UNDEF checking for pre-VFPv3
CPUs which only have D0-D15 : they now UNDEF for any access
to D16-D31, not merely when the smallest register in the
transfer list is in D16-D31.
This conversion does not try to share code between the single
precision and the double precision versions; this looks a bit
duplicative of code, but it leaves the door open for a future
refactoring which gets rid of the use of the "F0" registers
by inlining the various functions like gen_vfp_ld() and
gen_mov_F0_reg() which are hiding "if (dp) { ... } else { ... }"
conditionalisation.
Backports commit fa288de272c5c8a66d5eb683b123706a52bc7ad6 from qemu
Convert the VFP two-register transfer instructions to decodetree
(in the v8 Arm ARM these are the "Advanced SIMD and floating-point
64-bit move" encoding group).
Again, we expand out the sequences involving gen_vfp_msr() and
gen_msr_vfp().
Backports commit 81f681106eabe21c55118a5a41999fb7387fb714 from qemu
Convert the "single-precision" register moves to decodetree:
* VMSR
* VMRS
* VMOV between general purpose register and single precision
Note that the VMSR/VMRS conversions make our handling of
the "should this UNDEF?" checks consistent between the two
instructions:
* VMSR to MVFR0, MVFR1, MVFR2 now UNDEF from EL0
(previously was a nop)
* VMSR to FPSID now UNDEFs from EL0 or if VFPv3 or better
(previously was a nop)
* VMSR to FPINST and FPINST2 now UNDEF if VFPv3 or better
(previously would write to the register, which had no
guest-visible effect because we always UNDEF reads)
We also tighten up the decode: we were previously underdecoding
some SBZ or SBO bits.
The conversion of VMOV_single includes the expansion out of the
gen_mov_F0_vreg()/gen_vfp_mrs() and gen_mov_vreg_F0()/gen_vfp_msr()
sequences into the simpler direct load/store of the TCG temp via
neon_{load,store}_reg32(): we know in the new function that we're
always single-precision, we don't need to use the old-and-deprecated
cpu_F0* TCG globals, and we don't happen to have the declaration of
gen_vfp_msr() and gen_vfp_mrs() at the point in the file where the
new function is.
Backports commit a9ab50011aeda2dd012da99069e078379315ea18 from qemu
Convert the "double-precision" register moves to decodetree:
this covers VMOV scalar-to-gpreg, VMOV gpreg-to-scalar and VDUP.
Note that the conversion process has tightened up a few of the
UNDEF encoding checks: we now correctly forbid:
* VMOV-to-gpr with U:opc1:opc2 == 10x00 or x0x10
* VMOV-from-gpr with opc1:opc2 == 0x10
* VDUP with B:E == 11
* VDUP with Q == 1 and Vn<0> == 1
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
The accesses of elements < 32 bits could be improved by doing
direct ld/st of the right size rather than 32-bit read-and-shift
or read-modify-write, but we leave this for later cleanup,
since this series is generally trying to stick to fixing
the decode.
Backports commit 9851ed9269d214c0c6feba960dd14ff09e6c34b4 from qemu
The current VFP code has two different idioms for
loading and storing from the VFP register file:
1 using the gen_mov_F0_vreg() and similar functions,
which load and store to a fixed set of TCG globals
cpu_F0s, CPU_F0d, etc
2 by direct calls to tcg_gen_ld_f64() and friends
We want to phase out idiom 1 (because the use of the
fixed globals is a relic of a much older version of TCG),
but idiom 2 is quite longwinded:
tcg_gen_ld_f64(tmp, cpu_env, vfp_reg_offset(true, reg))
requires us to specify the 64-bitness twice, once in
the function name and once by passing 'true' to
vfp_reg_offset(). There's no guard against accidentally
passing the wrong flag.
Instead, let's move to a convention of accessing 64-bit
registers via the existing neon_load_reg64() and
neon_store_reg64(), and provide new neon_load_reg32()
and neon_store_reg32() for the 32-bit equivalents.
Implement the new functions and use them in the code in
translate-vfp.inc.c. We will convert the rest of the VFP
code as we do the decodetree conversion in subsequent
commits.
Backports commit 160f3b64c5cc4c8a09a1859edc764882ce6ad6bf from qemu
Move the trans_*() functions we've just created from translate.c
to translate-vfp.inc.c. This is pure code motion with no textual
changes (this can be checked with 'git show --color-moved').
Backports commit f7bbb8f31f0761edbf0c64b7ab3c3f49c13612ea from qemu
Convert the VCVTA/VCVTN/VCVTP/VCVTM instructions to decodetree.
trans_VCVT() is temporarily left in translate.c.
Backports commit c2a46a914cd5c38fd0ee57ff0befc1c5bde27bcf from qemu
Convert the VRINTA/VRINTN/VRINTP/VRINTM instructions to decodetree.
Again, trans_VRINT() is temporarily left in translate.c.
Backports commit e3bb599d16e4678b228d80194cee328f894b1ceb from qemu
Convert the VMINNM and VMAXNM instructions to decodetree.
As with VSEL, we leave the trans_VMINMAXNM() function
in translate.c for the moment.
Backports commit f65988a1efdb42f9058db44297591491842e697c from qemu
Convert the VSEL instructions to decodetree.
We leave trans_VSEL() in translate.c for now as this allows
the patch to show just the changes from the old handle_vsel().
In the old code the check for "do D16-D31 exist" was hidden in
the VFP_DREG macro, and assumed that VFPv3 always implied that
D16-D31 exist. In the new code we do the correct ID register test.
This gives identical behaviour for most of our CPUs, and fixes
previously incorrect handling for Cortex-R5F, Cortex-M4 and
Cortex-M33, which all implement VFPv3 or better with only 16
double-precision registers.
Backports commit b3ff4b87b4ae08120a51fe12592725e1dca8a085 from qemu
At the moment our -cpu max for AArch32 supports VFP short-vectors
because we always implement them, even for CPUs which should
not have them. The following commits are going to switch to
using the correct ID-register-check to enable or disable short
vector support, so we need to turn it on explicitly for -cpu max,
because Cortex-A15 doesn't implement it.
We don't enable this for the AArch64 -cpu max, because the v8A
architecture never supports short-vectors.
Backports commit 973751fd798d41402d34f9f705c0c6d1633d0cda from qemu
The Cortex-R5F initfn was not correctly setting up the MVFR
ID register values. Fill these in, since some subsequent patches
will use ID register checks rather than CPU feature bit checks.
Backports commit 3de79d335c9aa7d726865e3933d9b21781032183 from qemu
Factor out the VFP access checking code so that we can use it in the
leaf functions of the decodetree decoder.
We call the function full_vfp_access_check() so we can keep
the more natural vfp_access_check() for a version which doesn't
have the 'ignore_vfp_enabled' flag -- that way almost all VFP
insns will be able to use vfp_access_check(s) and only the
special-register access function will have to use
full_vfp_access_check(s, ignore_vfp_enabled).
Backports commit 06db8196bba34776829020192ed623a0b22e6557 from qemu
Add the infrastructure for building and invoking a decodetree decoder
for the AArch32 VFP encodings. At the moment the new decoder covers
nothing, so we always fall back to the existing hand-written decode.
We need to have one decoder for the unconditional insns and one for
the conditional insns, as otherwise the patterns for conditional
insns would incorrectly match against the unconditional ones too.
Since translate.c is over 14,000 lines long and we're going to be
touching pretty much every line of the VFP code as part of the
decodetree conversion, we create a new translate-vfp.inc.c to hold
the code which deals with VFP in the new scheme. It should be
possible to convert this into a standalone translation unit
eventually, but the conversion process will be much simpler if we
simply #include it midway through translate.c to start with.
Backports commit 78e138bc1f672c145ef6ace74617db00eebaa2ba from qemu
The ARM pseudocode installs the error_code into the original
pointer, not the encrypted pointer. The difference applies
within the 7 bits of pac data; the result should be the sign
extension of bit 55.
Add a testcase to that effect.
Backports commit d67ebada159148bfdfde84871338738e4465e985 from qemu
The NSACR register allows secure code to configure the FPU
to be inaccessible to non-secure code. If the NSACR.CP10
bit is set then:
* NS accesses to the FPU trap as UNDEF (ie to NS EL1 or EL2)
* CPACR.{CP10,CP11} behave as if RAZ/WI
* HCPTR.{TCP11,TCP10} behave as if RAO/WI
Note that we do not implement the NSACR.NSASEDIS bit which
gates only access to Advanced SIMD, in the same way that
we don't implement the equivalent CPACR.ASEDIS and HCPTR.TASE.
Backports commit fc1120a7f5f2d4b601003205c598077d3eb11ad2 from qemu
Nothing in there so far, but all of the plumbing done
within the target ArchCPU state.
Backports commit 5b146dc716cfd247f99556c04e6e46fbd67565a0 from qemu
Now that we have ArchCPU, we can define this generically,
in the one place that needs it.
Backports commit 677c4d69ac21961e76a386f9bfc892a44923acc0 from qemu
Cleanup in the boilerplate that each target must define.
Replace arm_env_get_cpu with env_archcpu. The combination
CPU(arm_env_get_cpu) should have used ENV_GET_CPU to begin;
use env_cpu now.
Backports commit 2fc0cc0e1e034582f4718b1a2d57691474ccb6aa from qemu
Now that we have both ArchCPU and CPUArchState, we can define
this generically instead of via macro in each target's cpu.h.
Backports commit 29a0af618ddd21f55df5753c3e16b0625f534b3c from qemu
