Commit Graph

876 Commits

Author SHA1 Message Date
Peter Maydell
694058da94
target/arm: Convert double-precision register moves to decodetree
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
2019-06-13 17:11:56 -04:00
Peter Maydell
7265161108
target/arm: Add helpers for VFP register loads and stores
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
2019-06-13 17:01:59 -04:00
Peter Maydell
033a386ffb
target/arm: Move the VFP trans_* functions to translate-vfp.inc.c
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
2019-06-13 16:56:24 -04:00
Peter Maydell
e55d31a5ac
target/arm: Convert VCVTA/VCVTN/VCVTP/VCVTM to decodetree
Convert the VCVTA/VCVTN/VCVTP/VCVTM instructions to decodetree.
trans_VCVT() is temporarily left in translate.c.

Backports commit c2a46a914cd5c38fd0ee57ff0befc1c5bde27bcf from qemu
2019-06-13 16:54:42 -04:00
Peter Maydell
9fb01cb526
target/arm: Convert VRINTA/VRINTN/VRINTP/VRINTM to decodetree
Convert the VRINTA/VRINTN/VRINTP/VRINTM instructions to decodetree.
Again, trans_VRINT() is temporarily left in translate.c.

Backports commit e3bb599d16e4678b228d80194cee328f894b1ceb from qemu
2019-06-13 16:50:36 -04:00
Peter Maydell
4501daf010
target/arm: Convert VMINNM, VMAXNM to decodetree
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
2019-06-13 16:43:50 -04:00
Peter Maydell
3994dfd079
target/arm: Convert the VSEL instructions to decodetree
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
2019-06-13 16:41:22 -04:00
Peter Maydell
93adaa7de2
target/arm: Explicitly enable VFP short-vectors for aarch32 -cpu max
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
2019-06-13 16:38:01 -04:00
Peter Maydell
808d929d7c
target/arm: Fix Cortex-R5F MVFR values
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
2019-06-13 16:36:48 -04:00
Lioncash
b3cfede44f
target/arm: Make load_cpu_offset() take a DisasContext* instead of uc_struct*
Keeps it consistent with store_cpu_offset
2019-06-13 16:35:31 -04:00
Peter Maydell
78997058e4
target/arm: Factor out VFP access checking code
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
2019-06-13 16:33:38 -04:00
Peter Maydell
9732ebba5c
target/arm: Add stubs for AArch32 VFP decodetree
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
2019-06-13 16:24:37 -04:00
Richard Henderson
afaea6a291
target/arm: Fix output of PAuth Auth
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
2019-06-13 16:17:00 -04:00
Peter Maydell
230f8a091a
target/arm: Implement NSACR gating of floating point
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
2019-06-13 16:15:28 -04:00
Richard Henderson
7c32498b7f
target/arm: Use tcg_gen_gvec_bitsel
This replaces 3 target-specific implementations for BIT, BIF, and BSL.

Backports commit 3a7a2b4e5cf0d49cd8b14e8225af0310068b7d20 from qemu
2019-06-13 16:12:56 -04:00
Richard Henderson
8f53f09a05
cpu: Introduce CPUNegativeOffsetState
Nothing in there so far, but all of the plumbing done
within the target ArchCPU state.

Backports commit 5b146dc716cfd247f99556c04e6e46fbd67565a0 from qemu
2019-06-13 15:08:25 -04:00
Richard Henderson
a672b89e3b
cpu: Introduce cpu_set_cpustate_pointers
Consolidate some boilerplate from foo_cpu_initfn.

Backports commit 7506ed902eb97fe4e2a1dd16766c621d32ecc40d from qemu
2019-06-12 12:27:16 -04:00
Richard Henderson
ac176ccb38
cpu: Move ENV_OFFSET to exec/gen-icount.h
Now that we have ArchCPU, we can define this generically,
in the one place that needs it.

Backports commit 677c4d69ac21961e76a386f9bfc892a44923acc0 from qemu
2019-06-12 12:20:21 -04:00
Richard Henderson
b8bd543390
target/arm: Use env_cpu, env_archcpu
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
2019-06-12 11:34:08 -04:00
Richard Henderson
fbf91a6535
cpu: Replace ENV_GET_CPU with env_cpu
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
2019-06-12 11:16:16 -04:00
Richard Henderson
ae94fb5992
cpu: Define ArchCPU
For all targets, do this just before including exec/cpu-all.h.

Backports commit 2161a612b4e1d388046320bc464adefd6bba01a0 from qemu
2019-06-12 11:08:39 -04:00
Richard Henderson
e3f1f25996
cpu: Define CPUArchState with typedef
For all targets, do this just before including exec/cpu-all.h.

Backports commit 4f7c64b3819d559417615ed2b1d028ebc1a49580 from qemu
2019-06-12 11:06:36 -04:00
Richard Henderson
df2a890bd7
tcg: Split out target/arch/cpu-param.h
For all targets, into this new file move TARGET_LONG_BITS,
TARGET_PAGE_BITS, TARGET_PHYS_ADDR_SPACE_BITS,
TARGET_VIRT_ADDR_SPACE_BITS, and NB_MMU_MODES.

Include this new file from exec/cpu-defs.h.

This now removes the somewhat odd requirement that target/arch/cpu.h
defines TARGET_LONG_BITS before including exec/cpu-defs.h, so push the
bulk of the includes within target/arch/cpu.h to the top.

Backports commit 74433bf083b0766aba81534f92de13194f23ff3e from qemu
2019-06-10 19:35:46 -04:00
Alistair Francis
f8f3e50372
target/arm: Fix vector operation segfault
Commit 89e68b575 "target/arm: Use vector operations for saturation"
causes this abort() when booting QEMU ARM with a Cortex-A15:

0 0x00007ffff4c2382f in raise () at /usr/lib/libc.so.6
1 0x00007ffff4c0e672 in abort () at /usr/lib/libc.so.6
2 0x00005555559c1839 in disas_neon_data_insn (insn=<optimized out>, s=<optimized out>) at ./target/arm/translate.c:6673
3 0x00005555559c1839 in disas_neon_data_insn (s=<optimized out>, insn=<optimized out>) at ./target/arm/translate.c:6386
4 0x00005555559cd8a4 in disas_arm_insn (insn=4081107068, s=0x7fffe59a9510) at ./target/arm/translate.c:9289
5 0x00005555559cd8a4 in arm_tr_translate_insn (dcbase=0x7fffe59a9510, cpu=<optimized out>) at ./target/arm/translate.c:13612
6 0x00005555558d1d39 in translator_loop (ops=0x5555561cc580 <arm_translator_ops>, db=0x7fffe59a9510, cpu=0x55555686a2f0, tb=<optimized out>, max_insns=<optimized out>) at ./accel/tcg/translator.c:96
7 0x00005555559d10d4 in gen_intermediate_code (cpu=cpu@entry=0x55555686a2f0, tb=tb@entry=0x7fffd7840080 <code_gen_buffer+126091347>, max_insns=max_insns@entry=512) at ./target/arm/translate.c:13901
8 0x00005555558d06b9 in tb_gen_code (cpu=cpu@entry=0x55555686a2f0, pc=3067096216, cs_base=0, flags=192, cflags=-16252928, cflags@entry=524288) at ./accel/tcg/translate-all.c:1736
9 0x00005555558ce467 in tb_find (cf_mask=524288, tb_exit=1, last_tb=0x7fffd783e640 <code_gen_buffer+126084627>, cpu=0x1) at ./accel/tcg/cpu-exec.c:407
10 0x00005555558ce467 in cpu_exec (cpu=cpu@entry=0x55555686a2f0) at ./accel/tcg/cpu-exec.c:728
11 0x000055555588b0cf in tcg_cpu_exec (cpu=0x55555686a2f0) at ./cpus.c:1431
12 0x000055555588d223 in qemu_tcg_cpu_thread_fn (arg=0x55555686a2f0) at ./cpus.c:1735
13 0x000055555588d223 in qemu_tcg_cpu_thread_fn (arg=arg@entry=0x55555686a2f0) at ./cpus.c:1709
14 0x0000555555d2629a in qemu_thread_start (args=<optimized out>) at ./util/qemu-thread-posix.c:502
15 0x00007ffff4db8a92 in start_thread () at /usr/lib/libpthread.

This patch ensures that we don't hit the abort() in the second switch
case in disas_neon_data_insn() as we will return from the first case.

Backports commit 2f143d3ad1c05e91cf2cdf5de06d59a80a95e6c8 from qemu
2019-05-24 18:02:32 -04:00
Richard Henderson
9287750362
target/arm: Simplify BFXIL expansion
The mask implied by the extract is redundant with the one
implied by the deposit. Also, fix spelling of BFXIL.

Backports commit 87eb65a3c45c788a309986d48170a54a0d1c0705 from qemu
2019-05-24 18:01:26 -04:00
Richard Henderson
1778828644
target/arm: Use extract2 for EXTR
This is, after all, how we implement extract2 in tcg/aarch64.

Backports commit 80ac954c369e7e61bd1ed00cef07b63e11f9c734 from qemu
2019-05-24 17:58:58 -04:00
Richard Henderson
3dd7358a53
target/arm: Implement ARMv8.5-RNG
Use the newly introduced infrastructure for guest random numbers.

Backports commit de390645675966cce113bf5394445bc1f8d07c85 from qemu

(with the actual RNG portion disabled to preserve determinism for the
time being).
2019-05-23 15:03:23 -04:00
Richard Henderson
a8df33c37c
target/arm: Put all PAC keys into a structure
This allows us to use a single syscall to initialize them all.

Backports commit 108b3ba891408c4dce93df78261ec4aca38c0e2e from qemu
2019-05-23 14:54:06 -04:00
Richard Henderson
2a4a7b9391
tcg: Use tlb_fill probe from tlb_vaddr_to_host
Most of the existing users would continue around a loop which
would fault the tlb entry in via a normal load/store.

But for AArch64 SVE we have an existing emulation bug wherein we
would mark the first element of a no-fault vector load as faulted
(within the FFR, not via exception) just because we did not have
its address in the TLB. Now we can properly only mark it as faulted
if there really is no valid, readable translation, while still not
raising an exception. (Note that beyond the first element of the
vector, the hardware may report a fault for any reason whatsoever;
with at least one element loaded, forward progress is guaranteed.)

Backports commit 4811e9095c0491bc6f5450e5012c9c4796b9e59d from qemu
2019-05-16 18:27:03 -04:00
Richard Henderson
dab0061a0d
tcg: Use CPUClass::tlb_fill in cputlb.c
We can now use the CPUClass hook instead of a named function.

Create a static tlb_fill function to avoid other changes within
cputlb.c. This also isolates the asserts within. Remove the
named tlb_fill function from all of the targets.

Backports commit c319dc13579a92937bffe02ad2c9f1a550e73973 from qemu
2019-05-16 17:35:37 -04:00
Richard Henderson
31ecdb5341
target/arm: Convert to CPUClass::tlb_fill
Backports commit 7350d553b5066abdc662045d7db5cdb73d0f9d53 from qemu
2019-05-16 16:55:12 -04:00
Richard Henderson
552e48f14e
target/arm: Use tcg_gen_abs_i64 and tcg_gen_gvec_abs
Backports commit 4e027a710673f5d4dc6cff88728bcfd32e4c47b0 from qemu
2019-05-16 16:43:02 -04:00
Richard Henderson
6d1730048d
tcg: Add support for integer absolute value
Remove a function of the same name from target/arm/.
Use a branchless implementation of abs gleaned from gcc.

Backports commit ff1f11f7f8710a768f9313f24bd7f509d3db27e5 from qemu
2019-05-16 16:25:15 -04:00
Richard Henderson
c54b2776f6
tcg: Specify optional vector requirements with a list
Replace the single opcode in .opc with a null-terminated
array in .opt_opc. We still require that all opcodes be
used with the same .vece.

Validate the contents of this list with CONFIG_DEBUG_TCG.
All tcg_gen_*_vec functions will check any list active
during .fniv expansion. Swap the active list in and out
as we expand other opcodes, or take control away from the
front-end function.

Convert all existing vector aware front ends.

Backports commit 53229a7703eeb2bbe101a19a33ef22aaf960c65b from qemu
2019-05-16 15:05:02 -04:00
Peter Maydell
26cb1b8767
target/arm: Stop using variable length array in dc_zva
Currently the dc_zva helper function uses a variable length
array. In fact we know (as the comment above remarks) that
the length of this array is bounded because the architecture
limits the block size and QEMU limits the target page size.
Use a fixed array size and assert that we don't run off it.

Backports commit 63159601fb3e396b28da14cbb71e50ed3f5a0331 from qemu
2019-05-09 17:48:25 -04:00
Peter Maydell
7861820e94
target/arm: Implement XPSR GE bits
In the M-profile architecture, if the CPU implements the DSP extension
then the XPSR has GE bits, in the same way as the A-profile CPSR. When
we added DSP extension support we forgot to add support for reading
and writing the GE bits, which are stored in env->GE. We did put in
the code to add XPSR_GE to the mask of bits to update in the v7m_msr
helper, but forgot it in v7m_mrs. We also must not allow the XPSR we
pull off the stack on exception return to set the nonexistent GE bits.
Correct these errors:
* read and write env->GE in xpsr_read() and xpsr_write()
* only set GE bits on exception return if DSP present
* read GE bits for MRS if DSP present

Backports commit f1e2598c46d480c9e21213a244bc514200762828 from qemu
2019-05-09 17:46:31 -04:00
Lioncash
a71c027063
decodetree: Add DisasContext argument to !function expanders
This does require adjusting all existing users.

Backports commit 451e4ffdb0003ab5ed0d98bd37b385c076aba183 from qemu
2019-05-09 17:40:45 -04:00
Emilio G. Cota
1715f382b4
target/arm: check CF_PARALLEL instead of parallel_cpus
Thereby decoupling the resulting translated code from the current state
of the system.

Backports commit 2399d4e7cec22ecf1c51062d2ebfd45220dbaace from qemu
2019-05-04 22:44:32 -04:00
Peter Maydell
d4549fccfb
target/arm: Enable FPU for Cortex-M4 and Cortex-M33
Enable the FPU by default for the Cortex-M4 and Cortex-M33.

Backports commit 14fd0c31e26b88a2189b3f459b864d5e1faf302a from qemu
2019-04-30 11:29:26 -04:00
Peter Maydell
77ae3982b4
target/arm: Implement VLLDM for v7M CPUs with an FPU
Implement the VLLDM instruction for v7M for the FPU present cas.

Backports commit 956fe143b4f254356496a0a1c479fa632376dfec from qemu
2019-04-30 11:27:54 -04:00
Peter Maydell
b483951046
target/arm: Implement VLSTM for v7M CPUs with an FPU
Implement the VLSTM instruction for v7M for the FPU present case.

Backports commit 019076b036da4444494de38388218040d9d3a26c from qemu
2019-04-30 11:25:44 -04:00
Peter Maydell
a976d7642a
target/arm: Implement M-profile lazy FP state preservation
The M-profile architecture floating point system supports
lazy FP state preservation, where FP registers are not
pushed to the stack when an exception occurs but are instead
only saved if and when the first FP instruction in the exception
handler is executed. Implement this in QEMU, corresponding
to the check of LSPACT in the pseudocode ExecuteFPCheck().

Backports commit e33cf0f8d8c9998a7616684f9d6aa0d181b88803 from qemu
2019-04-30 11:21:50 -04:00
Peter Maydell
72e5ae480d
target/arm: Add lazy-FP-stacking support to v7m_stack_write()
Pushing registers to the stack for v7M needs to handle three cases:
* the "normal" case where we pend exceptions
* an "ignore faults" case where we set FSR bits but
do not pend exceptions (this is used when we are
handling some kinds of derived exception on exception entry)
* a "lazy FP stacking" case, where different FSR bits
are set and the exception is pended differently

Implement this by changing the existing flag argument that
tells us whether to ignore faults or not into an enum that
specifies which of the 3 modes we should handle.

Backports commit a356dacf647506bccdf8ecd23574246a8bf615ac from qemu
2019-04-30 10:59:53 -04:00
Peter Maydell
b1d6bd2792
target/arm: New function armv7m_nvic_set_pending_lazyfp()
In the v7M architecture, if an exception is generated in the process
of doing the lazy stacking of FP registers, the handling of
possible escalation to HardFault is treated differently to the normal
approach: it works based on the saved information about exception
readiness that was stored in the FPCCR when the stack frame was
created. Provide a new function armv7m_nvic_set_pending_lazyfp()
which pends exceptions during lazy stacking, and implements
this logic.

This corresponds to the pseudocode TakePreserveFPException().

Backports the relevant parts of commit
a99ba8ab1601904e0fa20325192fc850362ce80e from qemu
2019-04-30 10:56:54 -04:00
Peter Maydell
3fff653e20
target/arm: New helper function arm_v7m_mmu_idx_all()
Add a new helper function which returns the MMU index to use
for v7M, where the caller specifies all of the security
state, privilege level and whether the execution priority
is negative, and reimplement the existing
arm_v7m_mmu_idx_for_secstate_and_priv() in terms of it.

We are going to need this for the lazy-FP-stacking code.

Backports commit fa6252a988dbe440cd6087bf93cbe0887f0c401b from qemu
2019-04-30 10:54:26 -04:00
Peter Maydell
719231b4c0
target/arm: Activate M-profile floating point context when FPCCR.ASPEN is set
The M-profile FPCCR.ASPEN bit indicates that automatic floating-point
context preservation is enabled. Before executing any floating-point
instruction, if FPCCR.ASPEN is set and the CONTROL FPCA/SFPA bits
indicate that there is no active floating point context then we
must create a new context (by initializing FPSCR and setting
FPCA/SFPA to indicate that the context is now active). In the
pseudocode this is handled by ExecuteFPCheck().

Implement this with a new TB flag which tracks whether we
need to create a new FP context.

Backports commit 6000531e19964756673a5f4b694a649ef883605a from qemu
2019-04-30 10:51:31 -04:00
Peter Maydell
87c8c0fde7
target/arm: Set FPCCR.S when executing M-profile floating point insns
The M-profile FPCCR.S bit indicates the security status of
the floating point context. In the pseudocode ExecuteFPCheck()
function it is unconditionally set to match the current
security state whenever a floating point instruction is
executed.

Implement this by adding a new TB flag which tracks whether
FPCCR.S is different from the current security state, so
that we only need to emit the code to update it in the
less-common case when it is not already set correctly.

Note that we will add the handling for the other work done
by ExecuteFPCheck() in later commits.

Backports commit 6d60c67a1a03be32c3342aff6604cdc5095088d1 from qemu
2019-04-30 10:50:17 -04:00
Peter Maydell
8d726490ff
target/arm: Overlap VECSTRIDE and XSCALE_CPAR TB flags
We are close to running out of TB flags for AArch32; we could
start using the cs_base word, but before we do that we can
economise on our usage by sharing the same bits for the VFP
VECSTRIDE field and the XScale XSCALE_CPAR field. This
works because no XScale CPU ever had VFP.

Backports commit ea7ac69d124c94c6e5579145e727adec9ccbefef from qemu
2019-04-30 10:45:14 -04:00
Peter Maydell
3c1f3548c4
target/arm: Move NS TBFLAG from bit 19 to bit 6
Move the NS TBFLAG down from bit 19 to bit 6, which has not
been used since commit c1e3781090b9d36c60 in 2015, when we
started passing the entire MMU index in the TB flags rather
than just a 'privilege level' bit.

This rearrangement is not strictly necessary, but means that
we can put M-profile-only bits next to each other rather
than scattered across the flag word.

Backports commit 7fbb535f7aeb22896fedfcf18a1eeff48165f1d7 from qemu
2019-04-30 10:41:04 -04:00
Peter Maydell
86776d451e
target/arm: Handle floating point registers in exception return
Handle floating point registers in exception return.
This corresponds to pseudocode functions ValidateExceptionReturn(),
ExceptionReturn(), PopStack() and ConsumeExcStackFrame().

Backports commit 6808c4d2d2826920087533f517472c09edc7b0d2 from qemu
2019-04-30 10:40:12 -04:00