Commit Graph

120 Commits

Author SHA1 Message Date
David Miller
ea0a1053e2 s390x/tcg: Implement Miscellaneous-Instruction-Extensions Facility 3 for the s390x
implements:
AND WITH COMPLEMENT   (NCRK, NCGRK)
NAND                  (NNRK, NNGRK)
NOT EXCLUSIVE OR      (NXRK, NXGRK)
NOR                   (NORK, NOGRK)
OR WITH COMPLEMENT    (OCRK, OCGRK)
SELECT                (SELR, SELGR)
SELECT HIGH           (SELFHR)
MOVE RIGHT TO LEFT    (MVCRL)
POPULATION COUNT      (POPCNT)

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/737
Signed-off-by: David Miller <dmiller423@gmail.com>
Message-Id: <20220223223117.66660-2-dmiller423@gmail.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2022-02-28 11:29:15 +01:00
David Hildenbrand
eaa0feea75 s390x/tcg: check for addressing exceptions for RRBE, SSKE and ISKE
Let's replace the ram_size check by a proper physical address space
check (for example, to prepare for memory hotplug), trigger addressing
exceptions and trace the return value of the storage key getter/setter.

Provide an helper mmu_absolute_addr_valid() to be used in other context
soon. Always test for "read" instead of "write" as we are not actually
modifying the page itself.

Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210903155514.44772-5-david@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2021-09-06 16:24:05 +02:00
Ulrich Weigand
2876105704 target/s390x: Fix CC set by CONVERT TO FIXED/LOGICAL
The FP-to-integer conversion instructions need to set CC 3 whenever
a "special case" occurs; this is the case whenever the instruction
also signals the IEEE invalid exception.  (See e.g. figure 19-18
in the Principles of Operation.)

However, qemu currently will set CC 3 only in the case where the
input was a NaN.  This is indeed one of the special cases, but
there are others, most notably the case where the input is out
of range of the target data type.

This patch fixes the problem by switching these instructions to
the "static" CC method and computing the correct result directly
in the helper.  (It cannot be re-computed later as the information
about the invalid exception is no longer available.)

This fixes a bug observed when running the wasmtime test suite
under the s390x-linux-user target.

Signed-off-by: Ulrich Weigand <ulrich.weigand@de.ibm.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210630105058.GA29130@oc3748833570.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2021-07-07 13:57:25 +02:00
David Hildenbrand
da4807527f s390x/tcg: Implement VECTOR FP (MAXIMUM|MINIMUM)
For IEEE functions, we can reuse the softfloat implementations. For the
other functions, implement it generically for 32bit/64bit/128bit -
carefully taking care of all weird special cases according to the tables
defined in the PoP.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210608092337.12221-24-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2021-06-21 08:48:21 +02:00
David Hildenbrand
f02497306e s390x/tcg: Implement VECTOR FP NEGATIVE MULTIPLY AND (ADD|SUBTRACT)
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210608092337.12221-23-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2021-06-21 08:48:21 +02:00
David Hildenbrand
e257abc8de s390x/tcg: Implement 32/128 bit for VECTOR FP MULTIPLY AND (ADD|SUBTRACT)
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210608092337.12221-22-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2021-06-21 08:48:21 +02:00
David Hildenbrand
a38b5a0eab s390x/tcg: Implement 32/128 bit for VECTOR FP TEST DATA CLASS IMMEDIATE
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210608092337.12221-21-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2021-06-21 08:48:21 +02:00
David Hildenbrand
9cbc8be05a s390x/tcg: Implement 128 bit for VECTOR FP LOAD ROUNDED
128 bit -> 64 bit, there is only a single element to process.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210608092337.12221-19-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2021-06-21 08:48:21 +02:00
David Hildenbrand
2e96005ed8 s390x/tcg: Implement 64 bit for VECTOR FP LOAD LENGTHENED
64 bit -> 128 bit, there is only a single final element.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210608092337.12221-18-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2021-06-21 08:48:21 +02:00
David Hildenbrand
1c6b5b47da s390x/tcg: Implement 32/128 bit for VECTOR FP COMPARE (AND SIGNAL) SCALAR
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210608092337.12221-17-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2021-06-21 08:48:21 +02:00
David Hildenbrand
e384332cb5 s390x/tcg: Implement 32/128 bit for VECTOR FP COMPARE *
In addition to 32/128bit variants, we also have to support the
"Signal-on-QNaN (SQ)" bit.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210608092337.12221-16-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2021-06-21 08:48:21 +02:00
David Hildenbrand
acb269a4cd s390x/tcg: Implement 32/128 bit for VECTOR (LOAD FP INTEGER|FP SQUARE ROOT)
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210608092337.12221-15-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2021-06-21 08:48:21 +02:00
David Hildenbrand
0987961da9 s390x/tcg: Implement 32/128 bit for VECTOR FP (ADD|DIVIDE|MULTIPLY|SUBTRACT)
In case of 128bit, we always have a single element. Add new helpers for
reading/writing 32/128 bit floats.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210608092337.12221-14-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2021-06-21 08:48:21 +02:00
David Hildenbrand
2a785dfb50 s390x/tcg: Implement VECTOR BIT PERMUTE
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210608092337.12221-12-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2021-06-21 08:48:21 +02:00
David Hildenbrand
977e43d977 s390x/tcg: Simplify vflr64() handling
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210608092337.12221-10-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2021-06-21 08:48:21 +02:00
David Hildenbrand
860b707bbb s390x/tcg: Simplify vfll32() handling
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210608092337.12221-9-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2021-06-21 08:48:21 +02:00
David Hildenbrand
34142ffdee s390x/tcg: Simplify vfma64() handling
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210608092337.12221-8-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2021-06-21 08:48:21 +02:00
David Hildenbrand
622ebe64ad s390x/tcg: Simplify vftci64() handling
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210608092337.12221-7-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2021-06-21 08:48:21 +02:00
David Hildenbrand
64deb65afe s390x/tcg: Simplify vfc64() handling
Pass the m5 field via simd_data() and don't provide specialized handlers
for single-element variants.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210608092337.12221-6-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2021-06-21 08:48:21 +02:00
David Hildenbrand
21bd6ea2b3 s390x/tcg: Simplify vop64_2() handling
Let's rework our macros and simplify. We still need helper functions in
most cases due to the different parameters types.

Next, we'll only have 32/128bit variants for vfi and vfsq, so special
case the others.

Note that for vfsq, the XxC and erm passed in the simd_data() will never be
set, resulting in the same behavior.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210608092337.12221-5-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2021-06-21 08:48:21 +02:00
David Hildenbrand
863b9507a6 s390x/tcg: Simplify vop64_3() handling
Let's simplify, reworking our handler generation, passing the whole "m5"
register content and not providing specialized handlers for "se", and
reading/writing proper float64 values using new helpers.

Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210608092337.12221-4-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2021-06-21 08:48:21 +02:00
David Hildenbrand
1a3c443c43 target/s390x: Store r1/r2 for page-translation exceptions during MVPG
The PoP states:

    When EDAT-1 does not apply, and a program interruption due to a
    page-translation exception is recognized by the MOVE PAGE
    instruction, the contents of the R1 field of the instruction are
    stored in bit positions 0-3 of location 162, and the contents of
    the R2 field are stored in bit positions 4-7.

    If [...] an ASCE-type, region-first-translation,
    region-second-translation, region-third-translation, or
    segment-translation exception was recognized, the contents of
    location 162 are unpredictable.

So we have to write r1/r2 into the lowcore on page-translation
exceptions. Simply handle all exceptions inside our mvpg helper now.

Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Tested-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210315085449.34676-3-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2021-03-15 11:03:20 +01:00
David Hildenbrand
20d143e2ca s390x/tcg: Implement MONITOR CALL
Recent upstream Linux uses the MONITOR CALL instruction for things like
BUG_ON() and WARN_ON(). We currently inject an operation exception when
we hit a MONITOR CALL instruction - which is wrong, as the instruction
is not glued to specific CPU features.

Doing a simple WARN_ON_ONCE() currently results in a panic:
  [   18.162801] illegal operation: 0001 ilc:2 [#1] SMP
  [   18.162889] Modules linked in:
  [...]
  [   18.165476] Kernel panic - not syncing: Fatal exception: panic_on_oops

With a proper implementation, we now get:
  [   18.242754] ------------[ cut here ]------------
  [   18.242855] WARNING: CPU: 7 PID: 1 at init/main.c:1534 [...]
  [   18.242919] Modules linked in:
  [...]
  [   18.246262] ---[ end trace a420477d71dc97b4 ]---
  [   18.259014] Freeing unused kernel memory: 4220K

Reported-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20200918085122.26132-1-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2020-10-02 13:52:49 +02:00
Richard Henderson
cea94ba36d target/s390x: Use tcg_gen_gvec_rotl{i,s,v}
Merge VERLL and VERLLV into op_vesv and op_ves, alongside
all of the other vector shift operations.

Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2020-06-02 08:42:37 -07:00
Richard Henderson
5e34df7cc9 target/s390x: Implement LOAD/STORE TO REAL ADDRESS inline
These are trivially done by performing a memory operation
with the correct mmu_idx.  The only tricky part is using
get_address directly in order to get the address wrapped;
we cannot use la2 because of the format.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20191211203614.15611-3-richard.henderson@linaro.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-12-18 12:57:29 +01:00
Richard Henderson
ebed683c4e target/s390x: Split out helper_per_store_real
Split the PER handling for store-to-real-address into its
own helper function, conditionally called when PER is
enabled, just as we do for per_branch and per_ifetch.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20191211203614.15611-2-richard.henderson@linaro.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-12-18 12:57:29 +01:00
David Hildenbrand
2bb525e20d s390x/tcg: MVST: Fix storing back the addresses to registers
24 and 31-bit address space handling is wrong when it comes to storing
back the addresses to the register.

While at it, read gprs 0 implicitly.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
2019-09-23 09:28:29 +02:00
David Hildenbrand
83b955f9a8 s390x/tcg: Implement VECTOR FP TEST DATA CLASS IMMEDIATE
We can reuse float64_dcmask().

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
2019-06-07 14:53:26 +02:00
David Hildenbrand
658a395f6c s390x/tcg: Implement VECTOR FP SUBTRACT
Similar to VECTOR FP ADD.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
2019-06-07 14:53:26 +02:00
David Hildenbrand
5938f20cb8 s390x/tcg: Implement VECTOR FP SQUARE ROOT
Simulate XxC=0 and ERM=0 (current mode), so we can use the existing
helper function.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
2019-06-07 14:53:26 +02:00
David Hildenbrand
c64c598402 s390x/tcg: Implement VECTOR FP MULTIPLY AND (ADD|SUBTRACT)
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
2019-06-07 14:53:26 +02:00
David Hildenbrand
8d47d4d212 s390x/tcg: Implement VECTOR FP MULTIPLY
Very similar to VECTOR FP DIVIDE.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
2019-06-07 14:53:26 +02:00
David Hildenbrand
4500ede452 s390x/tcg: Implement VECTOR LOAD ROUNDED
We can reuse some of the infrastructure introduced for
VECTOR FP CONVERT FROM FIXED 64-BIT and friends.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
2019-06-07 14:53:25 +02:00
David Hildenbrand
1a76e59da3 s390x/tcg: Implement VECTOR LOAD LENGTHENED
Take care of reading/indicating the 32-bit elements.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
2019-06-07 14:53:25 +02:00
David Hildenbrand
60d0ab29a1 s390x/tcg: Implement VECTOR LOAD FP INTEGER
We can reuse most of the infrastructure introduced for
VECTOR FP CONVERT FROM FIXED 64-BIT and friends.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
2019-06-07 14:53:25 +02:00
David Hildenbrand
817a1cec89 s390x/tcg: Implement VECTOR FP DIVIDE
We can reuse most of the infrastructure added for VECTOR FP ADD.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
2019-06-07 14:53:25 +02:00
David Hildenbrand
09c04e4b88 s390x/tcg: Implement VECTOR FP CONVERT TO LOGICAL 64-BIT
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
2019-06-07 14:53:25 +02:00
David Hildenbrand
35b3bb1c55 s390x/tcg: Implement VECTOR FP CONVERT TO FIXED 64-BIT
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
2019-06-07 14:53:25 +02:00
David Hildenbrand
9b8d1a387d s390x/tcg: Implement VECTOR FP CONVERT FROM LOGICAL 64-BIT
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
2019-06-07 14:53:25 +02:00
David Hildenbrand
bb03fd841c s390x/tcg: Implement VECTOR FP CONVERT FROM FIXED 64-BIT
1. We'll reuse op_vcdg() for similar instructions later, prepare for
   that.
2. We'll reuse vop64_2() later for other instructions.

We have to mangle the erm (effective rounding mode) and the m4 into
the simd_data(), and properly unmangle them again.

Make sure to restore the erm before triggering an exception.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
2019-06-07 14:53:25 +02:00
David Hildenbrand
2c806ab443 s390x/tcg: Implement VECTOR FP COMPARE (EQUAL|HIGH|HIGH OR EQUAL)
Provide for all three instructions all four combinations of cc bit and
s bit.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
2019-06-07 14:53:25 +02:00
David Hildenbrand
5b89f0fba2 s390x/tcg: Implement VECTOR FP COMPARE (AND SIGNAL) SCALAR
As far as I can see, there is only a tiny difference.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
2019-06-07 14:53:25 +02:00
David Hildenbrand
3a0eae8546 s390x/tcg: Implement VECTOR FP ADD
1. We'll reuse op_vfa() for similar instructions later, prepare for
   that.
2. We'll reuse vop64_3() for other instructions later.
3. Take care of modifying the vector register only if no trap happened.
 - on traps, flags are not updated and no elements are modified
 - traps don't modify the fpc flags
 - without traps, all exceptions of all elements are merged
4. We'll reuse check_ieee_exc() later when we need the XxC flag.

We have to check for exceptions after processing each element.
Provide separate handlers for single/all element processing. We'll do
the same for all applicable FP instructions.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
2019-06-07 14:53:25 +02:00
David Hildenbrand
13b0228f77 s390x/tcg: Implement VECTOR STRING RANGE COMPARE
Unfortunately, there is no easy way to avoid looping over all elements
in v2. Provide specialized variants for !cc,!rt/!cc,rt/cc,!rt/cc,rt and
all element types. Especially for different values of rt, the compiler
might be able to optimize the code a lot.

Add s390_vec_write_element().

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
2019-06-07 14:53:25 +02:00
David Hildenbrand
be6324c6b7 s390x/tcg: Implement VECTOR ISOLATE STRING
Logic mostly courtesy of Richard H.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
2019-06-07 14:53:25 +02:00
David Hildenbrand
074e99b3b5 s390x/tcg: Implement VECTOR FIND ELEMENT NOT EQUAL
Similar to VECTOR FIND ELEMENT EQUAL. Core logic courtesy of Richard H.

Add s390_vec_read_element() that can deal with element sizes.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
2019-06-07 14:53:25 +02:00
David Hildenbrand
8c0e1e58ce s390x/tcg: Implement VECTOR FIND ELEMENT EQUAL
Core logic courtesy of Richard H.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
2019-06-07 14:53:25 +02:00
David Hildenbrand
1fd286385c s390x/tcg: Implement VECTOR FIND ANY ELEMENT EQUAL
Complicated stuff. Provide two different helpers for CC an !CC handling.
We might want to add more helpers later.

zero_search() and match_index() are courtesy of Richard H.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
2019-06-07 14:53:25 +02:00
David Hildenbrand
db156ebfae s390x/tcg: Implement VECTOR TEST UNDER MASK
Let's return the cc value directly via cpu_env. Unfortunately there
isn't a simple way to calculate the value lazily - one would have to
calculate and store e.g. the population count of the mask and the
result so it can be evaluated in a cc helper.

But as VTM only sets the cc, we can assume the value will be needed soon
either way.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
2019-05-17 10:54:13 +02:00
David Hildenbrand
1ee2d7ba72 s390x/tcg: Implement VECTOR SUBTRACT COMPUTE BORROW INDICATION
Let's keep it simple for now and handle 8/16 bit elements via helpers.
Especially for 8/16, we could come up with some bit tricks.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
2019-05-17 10:54:13 +02:00