Commit Graph

21 Commits

Author SHA1 Message Date
David Hildenbrand bdcfcd445d s390x/tcg: Implement rounding mode and XxC for LOAD ROUNDED
With the floating-point extension facility, LOAD ROUNDED has
a rounding mode specification and the inexact-exception control (XxC).

Handle them just like e.g. LOAD FP INTEGER.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190218122710.23639-14-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-04 11:49:31 +01:00
David Hildenbrand dce0a58fd6 s390x/tcg: Implement XxC and checks for most FP instructions
With the floating-point extension facility
- CONVERT FROM LOGICAL
- CONVERT TO LOGICAL
- CONVERT TO FIXED
- CONVERT FROM FIXED
- LOAD FP INTEGER
have both, a rounding mode specification and the inexact-exception control
(XxC). Other instructions will be handled separatly.

Check for valid rounding modes and forward also the XxC (via m4). To avoid
a lot of boilerplate code and changes to the helpers, combine both, the
m3 and m4 field in a combined 32 bit TCG variable. Perform checks at
a central place, taking in account if the m3 or m4 field was ignore
before the floating-point extension facility was introduced.

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190218122710.23639-13-david@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-04 11:49:31 +01:00
David Hildenbrand cf97f9ff94 s390x/tcg: Prepare for IEEE-inexact-exception control (XxC)
Some instructions allow to suppress IEEE inexact exceptions.

z14 PoP, 9-23, "Suppression of Certain IEEE Exceptions"
    IEEE-inexact-exception control (XxC): Bit 1 of
    the M4 field is the XxC bit. If XxC is zero, recogni-
    tion of IEEE-inexact exception is not suppressed;
    if XxC is one, recognition of IEEE-inexact excep-
    tion is suppressed.

Especially, handling for overflow/unerflow remains as is, inexact is
reported along

z14 PoP, 9-23, "Suppression of Certain IEEE Exceptions"
    For example, the IEEE-inexact-exception control (XxC)
    has no effect on the DXC; that is, the DXC for IEEE-
    overflow or IEEE-underflow exceptions along with the
    detail for exact, inexact and truncated, or inexact and
    incremented, is reported according to the actual con-
    dition.

Follow up patches will wire it correctly up for the applicable
instructions.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190218122710.23639-12-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-04 11:49:31 +01:00
David Hildenbrand c0ee7015fd s390x/tcg: Refactor saving/restoring the bfp rounding mode
We want to reuse this in the context of vector instructions. So use
better matching names and introduce s390_restore_bfp_rounding_mode().

While at it, add proper newlines.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190218122710.23639-11-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-04 11:49:31 +01:00
David Hildenbrand b9c737f58e s390x/tcg: Check for exceptions in SET BFP ROUNDING MODE
Let's split handling of BFP/DFP rounding mode configuration. Also,
let's not reuse the sfpc handler, use a separate handler so we can
properly check for specification exceptions for SRNMB.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190218122710.23639-10-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-04 11:49:31 +01:00
David Hildenbrand 2aea83c672 s390x/tcg: Handle SET FPC AND LOAD FPC 3-bit BFP rounding modes
We already forward the 3 bits correctly in the translation functions. We
also have to handle them properly and check for specification
exceptions.

Setting an invalid rounding mode (BFP only, all DFP rounding modes)
results in a specification exception. Setting unassigned bits in the
fpc, results in a specification exception.

This fixes LOAD FPC (AND SIGNAL), SET FPC (AND SIGNAL). Also for,
SET BFP ROUNDING MODE, 3-bit rounding mode is now explicitly checked.

Note: TCG_CALL_NO_WG is required for sfpc handler, as we now inject
exceptions.

We won't be modeling abscence of the "floating-point extension facility"
for now, not necessary as most take the facility for granted without
checking.

z14 PoP, 9-23, "LOAD FPC"
    When the floating-point extension facility is
    installed, bits 29-31 of the second operand must
    specify a valid BFP rounding mode and bits 6-7,
    14-15, 24, and 28 must be zero; otherwise, a
    specification exception is recognized.

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190218122710.23639-9-david@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-04 11:49:31 +01:00
David Hildenbrand 8772bbe4e7 s390x/tcg: Fix simulated-IEEE exceptions
The trap is triggered based on priority of the enabled signaling flags.
Only overflow and underflow allow a concurrent inexact exception.

z14 PoP, 9-33, Figure 9-21

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190218122710.23639-8-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-04 11:49:31 +01:00
David Hildenbrand f66a0ecf23 s390x/tcg: Refactor SET FPC AND SIGNAL handling
We can directly work on the uint64_t value, no need for a temporary
uint32_t value.

Also cleanup and shorten the comments.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190218122710.23639-7-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-04 11:49:31 +01:00
David Hildenbrand 6d6ad1d14e s390x/tcg: Hide IEEE underflows in some scenarios
IEEE underflows are not reported when the mask bit is off and we don't
also have an inexact exception.

z14 PoP, 9-20, "IEEE Underflow":
    An IEEE-underflow exception is recognized for an
    IEEE target when the tininess condition exists and
    either: (1) the IEEE-underflow mask bit in the FPC
    register is zero and the result value is inexact, or (2)
    the IEEE-underflow mask bit in the FPC register is
    one.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190218122710.23639-6-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-04 11:49:31 +01:00
David Hildenbrand fcb9e9f2a1 s390x/tcg: Fix parts of IEEE exception handling
Many things are wrong and some parts cannot be fixed yet. Fix what we
can fix easily and add two FIXMEs:

The fpc flags are not updated in case an exception is actually injected.
Inexact exceptions have to be handled separately, as they are the only
exceptions that can coexist with underflows and overflows.

I reread the horribly complicated chapters in the PoP at least 5 times
and hope I got it right.

For references:
- z14 PoP, 9-18, "IEEE Exceptions"
- z14 PoP, 19-9, Figure 19-8

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190218122710.23639-5-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-04 11:49:31 +01:00
David Hildenbrand 4b70fc5497 s390x/tcg: Factor out conversion of softfloat exceptions
We want to reuse that function in vector instruction context. While at it,
cleanup the code, using defines for magic values and avoiding the
handcrafted bit conversion.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190218122710.23639-4-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-04 11:49:31 +01:00
David Hildenbrand 3af471f915 s390x/tcg: Fix rounding from float128 to uint64_t/uint32_t
Let's use the proper conversion functions now that we have them.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190218122710.23639-3-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-04 11:49:31 +01:00
David Hildenbrand fc7cc951b6 s390x/tcg: Fix TEST DATA CLASS instructions
Let's detect normal and denormal ("subnormal") numbers reliably. Also
test for quiet NaN's. As only one class is possible, test common cases
first.

While at it, use a better check to test for the mask bits in the data
class mask. The data class mask has 12 bits, whereby bit 0 is the
leftmost bit and bit 11 the rightmost bit. In the PoP an easy to read
table with the numbers is provided for the VECTOR FP TEST DATA CLASS
IMMEDIATE instruction, the table for TEST DATA CLASS is more confusing
as it is based on 64 bit values.

Factor the checks out into separate functions, as they will also be
needed for floating point vector instructions. We can use a makro to
generate the functions.

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190218122710.23639-2-david@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-04 11:49:31 +01:00
Thomas Huth 41c6a6dd84 target/s390x: Fix LGPL version in the file header comments
It's either "GNU *Library* General Public License version 2" or
"GNU Lesser General Public License version *2.1*", but there was
no "version 2.0" of the "Lesser" license. So assume that version
2.1 is meant here.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <1548769067-20792-1-git-send-email-thuth@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2019-01-30 11:04:02 +01:00
David Hildenbrand bbf6ea3bd9 s390x/tcg: factor out and fix DATA exception injection
The DXC is to be stored in the low core, and only in the FPC in case AFP
is enabled in CR0. Stub is not required in current code, but this way
we never run into problems.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20180927130303.12236-3-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2018-10-04 10:32:39 +02:00
Richard Henderson d0cfecb50d target/s390x: Remove floatX_maybe_silence_nan from conversions
This is now handled properly by the generic softfloat code.

Cc: Alexander Graf <agraf@suse.de>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2018-05-17 15:27:15 -07:00
Alex Bennée 24f91e81b6 target/*/cpu.h: remove softfloat.h
As cpu.h is another typically widely included file which doesn't need
full access to the softfloat API we can remove the includes from here
as well. Where they do need types it's typically for float_status and
the rounding modes so we move that to softfloat-types.h as well.

As a result of not having softfloat in every cpu.h call we now need to
add it to various helpers that do need the full softfloat.h
definitions.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
[For PPC parts]
Acked-by: David Gibson <david@gibson.dropbear.id.au>
2018-02-21 10:20:24 +00:00
David Hildenbrand 7693f77a7f s390x/tcg: get rid of runtime_exception()
Let's use s390_program_interrupt() instead.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20171130162744.25442-3-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2017-12-14 17:56:54 +01:00
David Hildenbrand 4e58b838dd target/s390x: introduce internal.h
cpu.h should only contain what really has to be accessed outside of
target/s390x/. Add internal.h which can only be used inside target/s390x/.

Move everything that isn't fast enough to run away and restructure it
right away. We'll move all kvm_* stuff later.

Minor style fixes to avoid checkpatch warning to:
- struct Lowcore: "{" goes into same line as typedef
- struct LowCore: add spaces around "-" in array length calculations
- time2tod() and tod2time(): move "{" to separate line
- get_per_atmid(): add space between ")" and "?". Move cases by one char.
- get_per_atmid(): drop extra paremthesis around (1 << 6)

Change license of new file to GPL2+ and keep copyright notice.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170818114353.13455-15-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2017-08-30 18:23:25 +02:00
Aurelien Jarno 9c8be59836 target/s390x: implement COMPARE AND SIGNAL
These functions differ from COMPARE by generating an exception for a
QNaN input. Use the non quiet version of floatXX_compare.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Message-Id: <20170531220129.27724-10-aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-06-06 15:20:38 -07:00
Thomas Huth fcf5ef2ab5 Move target-* CPU file into a target/ folder
We've currently got 18 architectures in QEMU, and thus 18 target-xxx
folders in the root folder of the QEMU source tree. More architectures
(e.g. RISC-V, AVR) are likely to be included soon, too, so the main
folder of the QEMU sources slowly gets quite overcrowded with the
target-xxx folders.
To disburden the main folder a little bit, let's move the target-xxx
folders into a dedicated target/ folder, so that target-xxx/ simply
becomes target/xxx/ instead.

Acked-by: Laurent Vivier <laurent@vivier.eu> [m68k part]
Acked-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> [tricore part]
Acked-by: Michael Walle <michael@walle.cc> [lm32 part]
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> [s390x part]
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> [s390x part]
Acked-by: Eduardo Habkost <ehabkost@redhat.com> [i386 part]
Acked-by: Artyom Tarasenko <atar4qemu@gmail.com> [sparc part]
Acked-by: Richard Henderson <rth@twiddle.net> [alpha part]
Acked-by: Max Filippov <jcmvbkbc@gmail.com> [xtensa part]
Reviewed-by: David Gibson <david@gibson.dropbear.id.au> [ppc part]
Acked-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com> [cris&microblaze part]
Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn> [unicore32 part]
Signed-off-by: Thomas Huth <thuth@redhat.com>
2016-12-20 21:52:12 +01:00