Commit Graph

522 Commits

Author SHA1 Message Date
David Hildenbrand
2c7590c8ea s390x/tcg: Implement VECTOR UNPACK *
Combine all variant in a single handler. As source and destination
have different element sizes, we can't use gvec expansion. Expand
manually. Also watch out for overlapping source and destination
registers. Use a safe evaluation order depending on the operation.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190307121539.12842-33-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
David Hildenbrand
0e0a5b49ad s390x/tcg: Implement VECTOR STORE WITH LENGTH
Very similar to VECTOR LOAD WITH LENGTH, just the opposite direction.
Properly probe write access before modifying memory.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190307121539.12842-32-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
David Hildenbrand
29b8bcf140 s390x/tcg: Implement VECTOR STORE MULTIPLE
Similar to VECTOR LOAD MULTIPLE, just the opposite direction. Probe
write access first.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190307121539.12842-31-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
David Hildenbrand
7b9a236ea7 s390x/tcg: Implement VECTOR STORE ELEMENT
As we only store one element, there is nothing to consider regarding
exceptions.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190307121539.12842-30-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
David Hildenbrand
15e12add0b s390x/tcg: Implement VECTOR STORE
Properly probe the whole access first.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190307121539.12842-29-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
David Hildenbrand
c5a7392cfb s390x/tcg: Provide probe_write_access helper
Instead of checking e.g. the first access on every touched page, we should
check the actual access, otherwise we might get false positives when Low
Address Protection (LAP) is active. As probe_write() can only deal with
accesses to one page, we have to loop.

Use i64 for the length, although not needed - easier to reuse
TCG temps we already have in the translation functions where this will
be used. Also allow it to be used from other helpers.

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190307121539.12842-28-david@redhat.com>
[CH: add missing page_check_range()]
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
David Hildenbrand
a2338cfb07 s390x/tcg: Implement VECTOR SIGN EXTEND TO DOUBLEWORD
Load both elements signed and store them into the two 64 bit elements.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190307121539.12842-27-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
David Hildenbrand
db23070c76 s390x/tcg: Implement VECTOR SELECT
Provide an implementation based on i64 and on real host vectors.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190307121539.12842-26-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
David Hildenbrand
7007ec27a9 s390x/tcg: Implement VECTOR SCATTER ELEMENT
Similar to VECTOR GATHER ELEMENT, but the other direction.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190307121539.12842-25-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
David Hildenbrand
3a338e29df s390x/tcg: Implement VECTOR REPLICATE IMMEDIATE
Like VECTOR REPLICATE, but the element to be replicated comes from an
immediate.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190307121539.12842-24-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
David Hildenbrand
28d08731b1 s390x/tcg: Implement VECTOR REPLICATE
Replicate via the special gvec helper.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190307121539.12842-23-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
David Hildenbrand
66bb3333bc s390x/tcg: Implement VECTOR PERMUTE DOUBLEWORD IMMEDIATE
Read the whole input before modifying the destination vector.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190307121539.12842-22-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
David Hildenbrand
7aaf844d46 s390x/tcg: Implement VECTOR PERMUTE
Take care of overlying inputs and outputs by using a temporary vector.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190307121539.12842-21-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
David Hildenbrand
73946f0d55 s390x/tcg: Implement VECTOR PACK *
This is a big one. Luckily we only have a limited set of such nasty
instructions.

We'll implement all variants with helpers, except when sources and
the destination don't overlap for VECTOR PACK. Provide different helpers
when the cc is to be modified. We'll return the cc then via env->cc_op.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190307121539.12842-20-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
David Hildenbrand
2ff47e6cce s390x/tcg: Implement VECTOR MERGE (HIGH|LOW)
We cannot use gvec expansion as source and destination elements are
have different element numbers. So we'll expand using a fancy loop.
Also, we have to take care of overlapping source and destination
registers, therefore use a safe evaluation irder depending on the
operation.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190307121539.12842-19-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
David Hildenbrand
f6c7ff6757 s390x/tcg: Implement VECTOR LOAD WITH LENGTH
We can reuse the helper introduced along with VECTOR LOAD TO BLOCK
BOUNDARY. We just have to take care of converting the highest index into
a length.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190307121539.12842-18-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
David Hildenbrand
76dbd28935 s390x/tcg: Implement VECTOR LOAD VR FROM GRS DISJOINT
Fairly easy, just load from to gprs into a single vector.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190307121539.12842-17-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
David Hildenbrand
90e3af6bb8 s390x/tcg: Implement VECTOR LOAD VR ELEMENT FROM GR
Very similar to VECTOR LOAD GR FROM VR ELEMENT, just the opposite
direction. Also provide a fast path in case we don't care about the
register content.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190307121539.12842-16-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
David Hildenbrand
60e9e3f1b0 s390x/tcg: Implement VECTOR LOAD TO BLOCK BOUNDARY
Very similar to LOAD COUNT TO BLOCK BOUNDARY, but instead of only
calculating, the actual vector is loaded. Use a temporary vector to
not modify the real vector on exceptions. Initialize that one to zero,
to not leak any data. Provide a fast path if we're loading a full
vector.

As we don't have gvec ool handlers for single vectors, just calculate
the vector address manually.

We can reuse the helper later on for VECTOR LOAD WITH LENGTH. In fact,
we are going to name it "vll" right from the beginning, because that's
a better match.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190307121539.12842-15-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
David Hildenbrand
0a85f8257a s390x/tcg: Implement VECTOR LOAD MULTIPLE
Try to load the last element first. Access to the first element will
be checked afterwards. This way, we can guarantee that the vector is
not modified before we checked for all possible exceptions. (16 vectors
cannot cross more than two pages)

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190307121539.12842-14-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
David Hildenbrand
f180da83c0 s390x/tcg: Implement VECTOR LOAD LOGICAL ELEMENT AND ZERO
Fairly easy, zero out the vector before we load the desired element.
Load the element before touching the vector.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190307121539.12842-13-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
David Hildenbrand
5d203bea59 s390x/tcg: Implement VECTOR LOAD GR FROM VR ELEMENT
To avoid an helper, we have to do the actual calculation of the element
address (offset in cpu_env + cpu_env) manually. Factor that out into
get_vec_element_ptr_i64(). The same logic will be reused for "VECTOR
LOAD VR ELEMENT FROM GR".

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190307121539.12842-12-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
David Hildenbrand
e6790d3211 s390x/tcg: Implement VECTOR LOAD ELEMENT IMMEDIATE
Take care of properly sign-extending the immediate.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190307121539.12842-11-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
David Hildenbrand
4b66439463 s390x/tcg: Implement VECTOR LOAD ELEMENT
Fairly easy, load with desired size and store it into the right element.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190307121539.12842-10-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
David Hildenbrand
79c1620aea s390x/tcg: Implement VECTOR LOAD AND REPLICATE
We can use tcg_gen_gvec_dup_i64() to carry out the duplication.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190307121539.12842-9-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
David Hildenbrand
b4f5ae47d8 s390x/tcg: Implement VECTOR LOAD
When loading from memory, load both elements into temps first before
modifying the target vector

Loading with strange alingment from the end of the address space will
not properly wrap, we can ignore that for now.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190307121539.12842-8-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
David Hildenbrand
eeb11a90a6 s390x/tcg: Implement VECTOR GENERATE MASK
Add gen_gvec_dupi() for handling duplication of immediates, so it can
be reused later.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190307121539.12842-7-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
David Hildenbrand
64052062a4 s390x/tcg: Implement VECTOR GENERATE BYTE MASK
Let's optimize it for the common cases (setting a vector to zero or all
ones) - courtesy of Richard.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190307121539.12842-6-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
David Hildenbrand
6d841663be s390x/tcg: Implement VECTOR GATHER ELEMENT
Let's start with a more involved one, but it is the first in the list
of vector support instructions (introduced with the vector facility).

Good thing is, we need a lot of basic infrastructure for this. Reading
and writing vector elements as well as checking element validity.

All vector instruction related translation functions will reside in
translate_vx.inc.c, to be included in translate.c - similar to how
other architectures handle it.

While at it, directly add some documentation (which contains parts about
things added in follow-up patches, but splitting this up does not make
too much sense). Also add ES_* defines heavily used later.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190307121539.12842-5-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
David Hildenbrand
5b5d2090de s390x/tcg: Utilities for vector instruction helpers
We'll have to read/write vector elements quite frequently from helpers.
The tricky bit is properly taking care of endianess. Handle it similar
to aarch64.

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190307121539.12842-4-david@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
David Hildenbrand
b971a2fda3 s390x/tcg: Check vector register instructions at central point
Check them at a central point. We'll use a new instruction flag to
flag all vector instructions (IF_VEC) and handle it very similar to
AFP, whereby we use another unused position in the PSW mask to store
the state of vector register enablement per translation block.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190307121539.12842-3-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
David Hildenbrand
481accd4f5 s390x/tcg: Define vector instruction formats
These are the new instruction formats related to vector instructions as
up to the z14 (a.k.a. latest PoP).

As v2 appeares (like x2 in VRX) with d2/b2 in VRV, we have to assign it a
higher field number to avoid collisions.

Properly take care of the MSB (to be able to address 32 registers) for
each vector register field stored in the RXB field (Bit 36 - 30  for all
vector instructions). As we have 32 bit vector registers and the
"v" fields are only 4 bit in size, the 5th bit is stored in the RXB.
We use a new type to indicate that the MSB has to be fetched from the
RXB.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190307121539.12842-2-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
Thomas Huth
a5f5ca5eaf target/s390x: Remove non-architected entries from struct LowCore
There are some fields in our struct LowCore which apparently have
been copied from a very old version of the Linux kernel. These
fields are not architected in the "Principles of Operation", and
only used on these memory locations in Linux kernels older than
2.6.29. Newer Linux kernels moved the entries to different locations
or are not using them at all anymore. Thus we should never access
these fields from the QEMU side, so they should be removed.

While we're at it, also add a QEMU_BUILD_BUG_ON() statement to
assert that struct LowCore has the right size.

Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <1551775581-27989-1-git-send-email-thuth@redhat.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-11 09:31:01 +01:00
David Hildenbrand
df192fbc51 s390x: Add floating-point extension facility to "qemu" cpu model
The floating-point extension facility implemented certain changes to
BFP, HFP and DFP instructions.

As we don't implement HFP/DFP, we can ignore those completely. Related
to BFP, the changes include
- SET BFP ROUNDING MODE (SRNMB) instruction
- BFP-rounding-mode field in the FPC register is changed to 3 bits
- CONVERT FROM LOGICAL instructions
- CONVERT TO LOGICAL instructions
- Changes (rounding mode + XxC) added to
-- CONVERT TO FIXED
-- CONVERT FROM FIXED
-- LOAD FP INTEGER
-- LOAD ROUNDED
-- DIVIDE TO INTEGER

For TCG, we don't implement DIVIDE TO INTEGER, and it is harder to
implement, so skip that. Also, as we don't implement PFPO, we can skip
changes to that as well. The other parts are now implemented, we can
indicate the facility.

z14 PoP mentions that "The floating-point extension facility is installed
in the z/Architecture architectural mode. When bit 37 is one, bit 42 is
also one.", meaning that the DFP (decimal-floating-point) facility also
has to be indicated. We can ignore that for now.

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190218122710.23639-16-david@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-04 11:49:31 +01:00
David Hildenbrand
b12b103ecd s390x/tcg: Handle all rounding modes overwritten by BFP instructions
"round to nearest with ties away from 0" maps to float_round_ties_away.
"round to prepare for shorter precision" maps to float_round_to_odd.

As all instructions properly check for valid rounding modes in translate.c
we can add an assert. Fix one missing empty line.

Cc: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190218122710.23639-15-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-04 11:49:31 +01:00
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
David Hildenbrand
6d9303322e s390x/tcg: Implement LOAD COUNT TO BLOCK BOUNDARY
Use a new CC helper to calculate the CC lazily if needed. While the
PoP mentions that "A 32-bit unsigned binary integer" is placed into the
first operand, there is no word telling that the other 32 bits (high
part) are left untouched. Maybe the other 32-bit are unpredictable.
So store 64 bit for now.

Bit magic courtesy of Richard.

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190225200318.16102-8-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
86b59624c4 s390x/tcg: Implement LOAD LENGTHENED short HFP to long HFP
Nice trick to load a 32 bit value into vector element 0 (32 bit element
size) from memory, zeroing out element1. The short HFP to long HFP
conversion really only is a shift.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190225200318.16102-7-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-03-04 11:49:31 +01:00