This patch modifies SoftFloat library so that it can be configured in
run-time in relation to the meaning of signaling NaN bit, while, at the
same time, strictly preserving its behavior on all existing platforms.
Background:
In floating-point calculations, there is a need for denoting undefined or
unrepresentable values. This is achieved by defining certain floating-point
numerical values to be NaNs (which stands for "not a number"). For additional
reasons, virtually all modern floating-point unit implementations use two
kinds of NaNs: quiet and signaling. The binary representations of these two
kinds of NaNs, as a rule, differ only in one bit (that bit is, traditionally,
the first bit of mantissa).
Up to 2008, standards for floating-point did not specify all details about
binary representation of NaNs. More specifically, the meaning of the bit
that is used for distinguishing between signaling and quiet NaNs was not
strictly prescribed. (IEEE 754-2008 was the first floating-point standard
that defined that meaning clearly, see [1], p. 35) As a result, different
platforms took different approaches, and that presented considerable
challenge for multi-platform emulators like QEMU.
Mips platform represents the most complex case among QEMU-supported
platforms regarding signaling NaN bit. Up to the Release 6 of Mips
architecture, "1" in signaling NaN bit denoted signaling NaN, which is
opposite to IEEE 754-2008 standard. From Release 6 on, Mips architecture
adopted IEEE standard prescription, and "0" denotes signaling NaN. On top of
that, Mips architecture for SIMD (also known as MSA, or vector instructions)
also specifies signaling bit in accordance to IEEE standard. MSA unit can be
implemented with both pre-Release 6 and Release 6 main processor units.
QEMU uses SoftFloat library to implement various floating-point-related
instructions on all platforms. The current QEMU implementation allows for
defining meaning of signaling NaN bit during build time, and is implemented
via preprocessor macro called SNAN_BIT_IS_ONE.
On the other hand, the change in this patch enables SoftFloat library to be
configured in run-time. This configuration is meant to occur during CPU
initialization, at the moment when it is definitely known what desired
behavior for particular CPU (or any additional FPUs) is.
The change is implemented so that it is consistent with existing
implementation of similar cases. This means that structure float_status is
used for passing the information about desired signaling NaN bit on each
invocation of SoftFloat functions. The additional field in float_status is
called snan_bit_is_one, which supersedes macro SNAN_BIT_IS_ONE.
IMPORTANT:
This change is not meant to create any change in emulator behavior or
functionality on any platform. It just provides the means for SoftFloat
library to be used in a more flexible way - in other words, it will just
prepare SoftFloat library for usage related to Mips platform and its
specifics regarding signaling bit meaning, which is done in some of
subsequent patches from this series.
Further break down of changes:
1) Added field snan_bit_is_one to the structure float_status, and
correspondent setter function set_snan_bit_is_one().
2) Constants <float16|float32|float64|floatx80|float128>_default_nan
(used both internally and externally) converted to functions
<float16|float32|float64|floatx80|float128>_default_nan(float_status*).
This is necessary since they are dependent on signaling bit meaning.
At the same time, for the sake of code cleanup and simplicity, constants
<floatx80|float128>_default_nan_<low|high> (used only internally within
SoftFloat library) are removed, as not needed.
3) Added a float_status* argument to SoftFloat library functions
XXX_is_quiet_nan(XXX a_), XXX_is_signaling_nan(XXX a_),
XXX_maybe_silence_nan(XXX a_). This argument must be present in
order to enable correct invocation of new version of functions
XXX_default_nan(). (XXX is <float16|float32|float64|floatx80|float128>
here)
4) Updated code for all platforms to reflect changes in SoftFloat library.
This change is twofolds: it includes modifications of SoftFloat library
functions invocations, and an addition of invocation of function
set_snan_bit_is_one() during CPU initialization, with arguments that
are appropriate for each particular platform. It was established that
all platforms zero their main CPU data structures, so snan_bit_is_one(0)
in appropriate places is not added, as it is not needed.
[1] "IEEE Standard for Floating-Point Arithmetic",
IEEE Computer Society, August 29, 2008.
Signed-off-by: Thomas Schwinge <thomas@codesourcery.com>
Signed-off-by: Maciej W. Rozycki <macro@codesourcery.com>
Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com>
Tested-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
Reviewed-by: Leon Alrae <leon.alrae@imgtec.com>
Tested-by: Leon Alrae <leon.alrae@imgtec.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
[leon.alrae@imgtec.com:
* cherry-picked 2 chunks from patch #2 to fix compilation warnings]
Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
exec-all.h contains TCG-specific definitions. It is not needed outside
TCG-specific files such as translate.c, exec.c or *helper.c.
One generic function had snuck into include/exec/exec-all.h; move it to
include/qom/cpu.h.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.
This commit was created with scripts/clean-includes.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1453832250-766-31-git-send-email-peter.maydell@linaro.org
Signed-off-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 1410626734-3804-5-git-send-email-rth@twiddle.net
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Rather than include helper.h with N values of GEN_HELPER, include a
secondary file that sets up the macros to include helper.h. This
minimizes the files that must be rebuilt when changing the macros
for file N.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Note that while such functions may exist both for *-user and softmmu,
only *-user uses the CPUState hook, while softmmu reuses the prototype
for calling it directly.
Signed-off-by: Andreas Färber <afaerber@suse.de>
# By Richard Henderson
# Via Richard Henderson
* rth/tcg-pull:
exec: Add both big- and little-endian memory helpers
tcg: Add qemu_ld_st_i32/64
tcg: Add TCGMemOp
configure: Remove CONFIG_QEMU_LDST_OPTIMIZATION
tcg: Add tcg-be-ldst.h
tcg: Add tcg-be-null.h
exec: Delete is_tcg_gen_code and GETRA_EXT
tcg-aarch64: Update to helper_ret_*_mmu routines
tcg: Merge tcg_register_helper into tcg_context_init
tcg: Add tcg-runtime.c helpers to all_helpers
tcg: Put target helper data into an array.
tcg: Remove stray semi-colons from target-*/helper.h
tcg: Move helper registration into tcg_context_init
target-m68k: Rename helpers.h to helper.h
tcg: Use a GHashTable for tcg_find_helper
tcg: Delete tcg_helper_get_name declaration
tcg-hppa: Remove tcg backend
Message-id: 1381440525-6666-1-git-send-email-rth@twiddle.net
Signed-off-by: Anthony Liguori <aliguori@amazon.com>
This brings the m68k target in line with all other targets.
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Since this is only read in cpu_copy() and linux-user has a global
cpu_model, drop the field from generic code.
Signed-off-by: Andreas Färber <afaerber@suse.de>
Change breakpoint_invalidate() argument to CPUState alongside.
Since all targets now assign a softmmu-only field, we can drop helpers
cpu_class_set_{do_unassigned_access,vmsd}() and device_class_set_vmsd().
Prepares for changing cpu_memory_rw_debug() argument to CPUState.
Acked-by: Max Filippov <jcmvbkbc@gmail.com> (for xtensa)
Signed-off-by: Andreas Färber <afaerber@suse.de>
Move it to qom/cpu.h to avoid issues with include order.
Change pc_acpi_smi_interrupt() opaque to X86CPU.
Signed-off-by: Andreas Färber <afaerber@suse.de>
Move it to qom/cpu.c to avoid build failures depending on include order
of cpu-qom.h and exec/cpu-all.h.
Change opaques of various ..._irq_handler() functions to the
appropriate CPU type to facilitate using cpu_reset_interrupt().
Fix Coding Style issues while at it (missing braces, indentation).
Signed-off-by: Andreas Färber <afaerber@suse.de>
Introduce realizefn and set realized = true in cpu_m68k_init().
Split off GDB registration to a new m68k_cpu_init_gdb() so that it can
be called from the realizefn.
Signed-off-by: Andreas Färber <afaerber@suse.de>
In the initial conversion of CPU models to QOM types, model names were
mapped 1:1 to type names. As a side effect this gained us a type "any",
which is now a device.
To avoid "-device any" silliness and to pave the way for compiling
multiple targets into one executable, adopt a <name>-<arch>-cpu scheme.
No functional changes for -cpu arguments or -cpu ? output.
Signed-off-by: Andreas Färber <afaerber@suse.de>
Consolidate model checking into a new m68k_cpu_class_by_name().
If the name matches an existing type, also check whether that type is
(a sub-type of) TYPE_M68K_CPU.
This fixes, e.g., -cpu ide-hd asserting.
Signed-off-by: Andreas Färber <afaerber@suse.de>
This generalizes {ARM,M68k,Alpha}CPUListState to avoid declaring it for
each target. Place it in cpu-common.h to avoid circular dependencies.
Signed-off-by: Andreas Färber <afaerber@suse.de>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
target_phys_addr_t is unwieldly, violates the C standard (_t suffixes are
reserved) and its purpose doesn't match the name (most target_phys_addr_t
addresses are not target specific). Replace it with a finger-friendly,
standards conformant hwaddr.
Outstanding patchsets can be fixed up with the command
git rebase -i --exec 'find -name "*.[ch]"
| xargs s/target_phys_addr_t/hwaddr/g' origin
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
In commit 1bba0dc932 cpu_reset()
was renamed to cpu_state_reset(), to allow introducing a new cpu_reset()
that would operate on QOM objects.
All callers have been updated except for one in target-mips, so drop all
implementations except for the one in target-mips and move the
declaration there until MIPSCPU reset can be fully QOM'ified.
Signed-off-by: Andreas Färber <afaerber@suse.de>
Acked-by: Michael Walle <michael@walle.cc> (for lm32)
Acked-by: Max Filippov <jcmvbkbc@gmail.com> (for xtensa)
Acked-by: Edgar E. Iglesias <edgar.iglesias@gmail.com> (for mb + cris)
Acked-by: Alexander Graf <agraf@suse.de> (for ppc)
Acked-by: Blue Swirl <blauwirbel@gmail.com>
Move code from cpu_m68k_set_model() into model-specific initfns
and inline the remaining parts into cpu_m68k_init().
Let m68k_cpu_list() print CPU classes alphabetically except for "any".
Signed-off-by: Andreas Färber <afaerber@suse.de>
Reviewed-by: Laurent Vivier <Laurent@Vivier.EU>
Tested-by: Laurent Vivier <Laurent@Vivier.EU>
Embed CPUM68KState as first member of QOM M68kCPU.
Drop cpu_m68k_close() in favor of object_delete().
Let CPUClass::reset() call cpu_state_reset() for now.
Signed-off-by: Andreas Färber <afaerber@suse.de>
Reviewed-by: Laurent Vivier <Laurent@Vivier.EU>
Tested-by: Laurent Vivier <Laurent@Vivier.EU>
Scripted conversion:
sed -i "s/CPUState/CPUM68KState/g" target-m68k/*.[hc]
sed -i "s/#define CPUM68KState/#define CPUState/" target-m68k/cpu.h
Signed-off-by: Andreas Färber <afaerber@suse.de>
Acked-by: Anthony Liguori <aliguori@us.ibm.com>
Frees the identifier cpu_reset for QOM CPUs (manual rename).
Don't hide the parameter type behind explicit casts, use static
functions with strongly typed argument to indirect.
Signed-off-by: Andreas Färber <afaerber@suse.de>
Reviewed-by: Anthony Liguori <aliguori@us.ibm.com>
Parameter is_softmmu (and its evil mutant twin brother is_softmuu)
is not used in cpu_*_handle_mmu_fault() functions, remove them
and adjust callers.
Acked-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
The code changed here is an unused data type name (evt_flush_occurred).
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
The softfloat functions float*_is_nan() were badly misnamed,
because they return true only for quiet NaNs, not for all NaNs.
Rename them to float*_is_quiet_nan() to more accurately reflect
what they do.
This change was produced by:
perl -p -i -e 's/_is_nan/_is_quiet_nan/g' $(git grep -l is_nan)
(with the results manually checked.)
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Nathan Froyd <froydnj@codesourcery.com>
Acked-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
fprintf_function uses format checking with GCC_FMT_ATTR.
Format errors were fixed in
* target-i386/helper.c
* target-mips/translate.c
* target-ppc/translate.c
Cc: Blue Swirl <blauwirbel@gmail.com>
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
Fix clang error:
CC m68k-softmmu/helper.o
/src/qemu/target-m68k/helper.c:773:33: error: if statement has empty body [-Wempty-body]
else if (val & (1ull << 47));
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
QEMU uses a fixed page size for the CPU TLB. If the guest uses large
pages then we effectively split these into multiple smaller pages, and
populate the corresponding TLB entries on demand.
When the guest invalidates the TLB by virtual address we must invalidate
all entries covered by the large page. However the address used to
invalidate the entry may not be present in the QEMU TLB, so we do not
know which regions to clear.
Implementing a full vaiable size TLB is hard and slow, so just keep a
simple address/mask pair to record which addresses may have been mapped by
large pages. If the guest invalidates this region then flush the
whole TLB.
Signed-off-by: Paul Brook <paul@codesourcery.com>
In the very least, a change like this requires discussion on the list.
The naming convention is goofy and it causes a massive merge problem. Something
like this _must_ be presented on the list first so people can provide input
and cope with it.
This reverts commit 99a0949b72.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
