Architecturally, Neon FP16 operations use the "standard FPSCR" like
all other Neon operations. However, this is defined in the Arm ARM
pseudocode as "a fixed value, except that FZ16 (and AHP) follow the
FPSCR bits". In QEMU, the softfloat float_status doesn't include
separate flush-to-zero for FP16 operations, so we must keep separate
fp_status for "Neon non-FP16" and "Neon fp16" operations, in the
same way we do already for the non-Neon "fp_status" vs "fp_status_f16".
Add the extra float_status field to the CPU state structure,
ensure it is correctly initialized and updated on FPSCR writes,
and make fpstatus_ptr(FPST_STD_F16) return a pointer to it.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20200806104453.30393-4-peter.maydell@linaro.org
Give the previously unnamed enum a typedef name. Use it in the
prototypes of compare functions. Use it to hold the results
of the compare functions.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Give the previously unnamed enum a typedef name. Use the packed
attribute so that we do not affect the layout of the float_status
struct. Use it in the prototypes of relevant functions.
Adjust switch statements as necessary to avoid compiler warnings.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
We have had this on the to-do list for quite some time.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The usual location for the env argument in the argument list of a TCG helper
is immediately after the return-value argument. recps_f32 and rsqrts_f32
differ in that they put it at the end.
Move the env argument to its usual place; this will allow us to
more easily use these helper functions with the gvec APIs.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20200512163904.10918-16-peter.maydell@linaro.org
These operations do not touch fp_status.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20200513163245.17915-12-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Our current usage of the isar_feature feature tests almost always
uses an _aa32_ test when the code path is known to be AArch32
specific and an _aa64_ test when the code path is known to be
AArch64 specific. There is just one exception: in the vfp_set_fpscr
helper we check aa64_fp16 to determine whether the FZ16 bit in
the FP(S)CR exists, but this code is also used for AArch32.
There are other places in future where we're likely to want
a general "does this feature exist for either AArch32 or
AArch64" check (typically where architecturally the feature exists
for both CPU states if it exists at all, but the CPU might be
AArch32-only or AArch64-only, and so only have one set of ID
registers).
Introduce a new category of isar_feature_* functions:
isar_feature_any_foo() should be tested when what we want to
know is "does this feature exist for either AArch32 or AArch64",
and always returns the logical OR of isar_feature_aa32_foo()
and isar_feature_aa64_foo().
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20200214175116.9164-4-peter.maydell@linaro.org
HCR_EL2.TID3 requires that AArch32 reads of MVFR[012] are trapped to
EL2, and HCR_EL2.TID0 does the same for reads of FPSID.
In order to handle this, introduce a new TCG helper function that
checks for these control bits before executing the VMRC instruction.
Tested with a hacked-up version of KVM/arm64 that sets the control
bits for 32bit guests.
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20191201122018.25808-4-maz@kernel.org
[PMM: move helper declaration to helper.h; make it
TCG_CALL_NO_WG]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
In commit e9d652824b we extracted the vfp_set_fpscr_to_host()
function but failed at calling it in the correct place, we call
it after xregs[ARM_VFP_FPSCR] is modified.
Fix by calling this function before we update FPSCR.
Reported-by: Laurent Desnogues <laurent.desnogues@gmail.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Laurent Desnogues <laurent.desnogues@gmail.com>
Tested-by: Laurent Desnogues <laurent.desnogues@gmail.com>
Message-id: 20190705124318.1075-1-philmd@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This code is specific to the SoftFloat floating-point
implementation, which is only used by TCG.
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20190701132516.26392-18-philmd@redhat.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The vfp_set_fpscr() helper contains code specific to the host
floating point implementation (here the SoftFloat library).
Extract this code to vfp_set_fpscr_from_host().
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20190701132516.26392-17-philmd@redhat.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The vfp_set_fpscr() helper contains code specific to the host
floating point implementation (here the SoftFloat library).
Extract this code to vfp_set_fpscr_to_host().
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20190701132516.26392-16-philmd@redhat.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
To ease the review of the next commit,
move the vfp_exceptbits_to_host() function directly after
vfp_exceptbits_from_host(). Amusingly the diff shows we
are moving vfp_get_fpscr().
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20190701132516.26392-15-philmd@redhat.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Since we'll move this code around, fix its style first.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20190701132516.26392-9-philmd@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Since commit 8c06fbdf36 checkpatch.pl enforce a new multiline
comment syntax. Since we'll move this code around, fix its style
first.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20190701132516.26392-8-philmd@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Cleanup in the boilerplate that each target must define.
Replace arm_env_get_cpu with env_archcpu. The combination
CPU(arm_env_get_cpu) should have used ENV_GET_CPU to begin;
use env_cpu now.
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Enforce that for M-profile various FPSCR bits which are RES0 there
but have defined meanings on A-profile are never settable. This
ensures that M-profile code can't enable the A-profile behaviour
(notably vector length/stride handling) by accident.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20190416125744.27770-2-peter.maydell@linaro.org
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20190215192302.27855-5-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
[PMM: fixed a couple of comment typos]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Move all of the fp helpers out of helper.c into a new file.
This is code movement only. Since helper.c has no copyright
header, take the one from cpu.h for the new file.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20190215192302.27855-3-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Peter Maydell
Richard Henderson
Marc Zyngier
Philippe Mathieu-Daudé