In OE project 4.15 linux kernel boot hang was observed under
single cpu aarch64 qemu. Kernel code was in a loop waiting for
vtimer arrival, spinning in TC generated blocks, while interrupt
was pending unprocessed. This happened because when qemu tried to
handle vtimer interrupt target had interrupts disabled, as
result flag indicating TCG exit, cpu->icount_decr.u16.high,
was cleared but arm_cpu_exec_interrupt function did not call
arm_cpu_do_interrupt to process interrupt. Later when target
reenabled interrupts, it happened without exit into main loop, so
following code that waited for result of interrupt execution
run in infinite loop.

To solve the problem instructions that operate on CPU sys state
(i.e enable/disable interrupt), and marked as DISAS_UPDATE,
should be considered as DISAS_EXIT variant, and should be
forced to exit back to main loop so qemu will have a chance
processing pending CPU state updates, including pending
interrupts.

This change brings consistency with how DISAS_UPDATE is treated
in aarch32 case.

CC: Peter Maydell <peter.maydell@linaro.org>
CC: Alex Bennée <alex.bennee@linaro.org>
CC: qemu-stable@nongnu.org
Suggested-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NVictor Kamensky <kamensky@cisco.com>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 1521526368-1996-1-git-send-email-kamensky@cisco.com
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180228193125.20577-13-richard.henderson@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
[PMM: renamed e1/e2/e3/e4 to use the same naming as the version
 of the pseudocode in the Arm ARM]
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>

Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180228193125.20577-12-richard.henderson@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180228193125.20577-7-richard.henderson@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180228193125.20577-6-richard.henderson@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180228193125.20577-5-richard.henderson@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

The integer size check was already outside of the opcode switch;
move the floating-point size check outside as well.  Unify the
size vs index adjustment between fp and integer paths.
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 20180228193125.20577-4-richard.henderson@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Include the U bit in the switches rather than testing separately.
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 20180228193125.20577-3-richard.henderson@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

This includes FMOV, FABS, FNEG, FSQRT and  FRINT[NPMZAXI]. We re-use
existing helpers to achieve this.
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180227143852.11175-32-alex.bennee@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

This covers the encoding group:

  Advanced SIMD scalar three same FP16

As all the helpers are already there it is simply a case of calling the
existing helpers in the scalar context.
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180227143852.11175-31-alex.bennee@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

I only needed to do a little light re-factoring to support the
half-precision helpers.
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180227143852.11175-30-alex.bennee@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Only one half-precision instruction has been added to this group.
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180227143852.11175-29-alex.bennee@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180227143852.11175-28-alex.bennee@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180227143852.11175-26-alex.bennee@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

We go with the localised helper.
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180227143852.11175-25-alex.bennee@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Now we have added f16 during the re-factoring we can simply call the
helper.
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180227143852.11175-24-alex.bennee@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Neither of these operations alter the floating point status registers
so we can do a pure bitwise operation, either squashing any sign
bit (ABS) or inverting it (NEG).
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180227143852.11175-22-alex.bennee@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

I've re-factored the handle_simd_intfp_conv helper to properly handle
half-precision as well as call plain conversion helpers when we are
not doing fixed point conversion.
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180227143852.11175-21-alex.bennee@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

I re-use the existing handle_2misc_fcmp_zero handler and tweak it
slightly to deal with the half-precision case.
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180227143852.11175-20-alex.bennee@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

This covers all the floating point convert operations.
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180227143852.11175-19-alex.bennee@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

This adds the full range of half-precision floating point to integral
instructions.
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180227143852.11175-18-alex.bennee@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

This actually covers two different sections of the encoding table:

   Advanced SIMD scalar two-register miscellaneous FP16
   Advanced SIMD two-register miscellaneous (FP16)

The difference between the two is covered by a combination of Q (bit
30) and S (bit 28). Notably the FRINTx instructions are only
available in the vector form.

This is just the decode skeleton which will be filled out by later
patches.
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180227143852.11175-17-alex.bennee@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

A bunch of the vectorised bitwise operations just operate on larger
chunks at a time. We can do the same for the new half-precision
operations by introducing some TWOHALFOP helpers which work on each
half of a pair of half-precision operations at once.

Hopefully all this hoop jumping will get simpler once we have
generically vectorised helpers here.
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180227143852.11175-16-alex.bennee@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

The helpers use the new re-factored muladd support in SoftFloat for
the float16 work.
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Message-id: 20180227143852.11175-15-alex.bennee@linaro.org
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

This includes FMAXNMP, FADDP, FMAXP, FMINNMP, FMINP.
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180227143852.11175-14-alex.bennee@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

As some of the constants here will also be needed
elsewhere (specifically for the upcoming SVE support) we move them out
to softfloat.h.
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180227143852.11175-13-alex.bennee@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180227143852.11175-12-alex.bennee@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

These use the generic float16_compare functionality which in turn uses
the common float_compare code from the softfloat re-factor.
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180227143852.11175-11-alex.bennee@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

The fprintf is only there for debugging as the skeleton is added to,
it will be removed once the skeleton is complete.
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180227143852.11175-10-alex.bennee@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

This is the initial decode skeleton for the Advanced SIMD three same
instruction group.

The fprintf is purely to aid debugging as the additional instructions
are added. It will be removed once the group is complete.
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180227143852.11175-9-alex.bennee@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

We do implement all the opcodes.
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180227143852.11175-8-alex.bennee@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

This implements the half-precision variants of the across vector
reduction operations. This involves a re-factor of the reduction code
which more closely matches the ARM ARM order (and handles 8 element
reductions).
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180227143852.11175-7-alex.bennee@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

As the rounding mode is now split between FP16 and the rest of
floating point we need to be explicit when tweaking it. Instead of
passing the CPU env we now pass the appropriate fpst pointer directly.
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180227143852.11175-6-alex.bennee@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Half-precision flush to zero behaviour is controlled by a separate
FZ16 bit in the FPCR. To handle this we pass a pointer to
fp_status_fp16 when working on half-precision operations. The value of
the presented FPCR is calculated from an amalgam of the two when read.
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180227143852.11175-5-alex.bennee@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

When storing to an AdvSIMD FP register, all of the high
bits of the SVE register are zeroed.  Therefore, call it
more often with is_q as a parameter.
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180211205848.4568-6-richard.henderson@linaro.org
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

This also makes sure that we get the correct ordering of
SVE vs FP exceptions.
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180211205848.4568-5-richard.henderson@linaro.org
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180211205848.4568-3-richard.henderson@linaro.org
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Add both SVE exception state and vector length.
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 20180123035349.24538-6-richard.henderson@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Change vfp.regs as a uint64_t to vfp.zregs as an ARMVectorReg.
The previous patches have made the change in representation
relatively painless.
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 20180123035349.24538-2-richard.henderson@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

This implements emulation of the new SM4 instructions that have
been added as an optional extension to the ARMv8 Crypto Extensions
in ARM v8.2.
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Message-id: 20180207111729.15737-5-ard.biesheuvel@linaro.org
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>