Move CPU TLB related methods to "exec/cputlb.h".
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Message-ID: <20241114011310.3615-19-philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The definition of which floatx80 encodings are invalid is
target-specific. Currently we handle this with an ifdef, but we
would like to defer this decision to runtime. In preparation, pass a
float_status argument to floatx80_invalid_encoding().
We will change the implementation from ifdef to looking at
the status argument in the following commit.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20250224111524.1101196-7-peter.maydell@linaro.org
Unlike the other float formats, whether a floatx80 value is
considered to be an Infinity is target-dependent. (On x86 if the
explicit integer bit is clear this is a "pseudo-infinity" and not a
valid infinity; m68k does not care about the value of the integer
bit.)
Currently we select this target-specific logic at compile time with
an ifdef. We're going to want to do this at runtime, so change the
floatx80_is_infinity() function to take a float_status.
This commit doesn't change any logic; we'll do that in the
next commit.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20250224111524.1101196-5-peter.maydell@linaro.org
The global const floatx80_infinity is (unlike all the other
float*_infinity values) target-specific, because whether the explicit
Integer bit is set or not varies between m68k and i386. We want to
be able to compile softfloat once for multiple targets, so we can't
continue to use a single global whose value needs to be different
between targets.
Replace the direct uses of floatx80_infinity in target/i386 with
calls to the new floatx80_default_inf() function. Note that because
we can ask the function for either a negative or positive infinity,
we don't need to change the sign of a positive infinity via
floatx80_chs() for the negative-Inf case.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20250224111524.1101196-4-peter.maydell@linaro.org
Message-id: 20250217125055.160887-4-peter.maydell@linaro.org
Currently we handle flushing of output denormals in uncanon_normal
always before we deal with rounding. This works for architectures
that detect tininess before rounding, but is usually not the right
place when the architecture detects tininess after rounding. For
example, for x86 the SDM states that the MXCSR FTZ control bit causes
outputs to be flushed to zero "when it detects a floating-point
underflow condition". This means that we mustn't flush to zero if
the input is such that after rounding it is no longer tiny.
At least one of our guest architectures does underflow detection
after rounding but flushing of denormals before rounding (MIPS MSA);
this means we need to have a config knob for this that is separate
from our existing tininess_before_rounding setting.
Add an ftz_detection flag. For consistency with
tininess_before_rounding, we make it default to "detect ftz after
rounding"; this means that we need to explicitly set the flag to
"detect ftz before rounding" on every existing architecture that sets
flush_to_zero, so that this commit has no behaviour change.
(This means more code change here but for the long term a less
confusing API.)
For several architectures the current behaviour is either
definitely or possibly wrong; annotate those with TODO comments.
These architectures are definitely wrong (and should detect
ftz after rounding):
* x86
* Alpha
For these architectures the spec is unclear:
* MIPS (for non-MSA)
* RX
* SH4
PA-RISC makes ftz detection IMPDEF, but we aren't setting the
"tininess before rounding" setting that we ought to.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
In commit 8adcff4ae7 ("fpu: handle raising Invalid for infzero in
pick_nan_muladd") we changed the handling of 0 * Inf + QNaN to always
raise the Invalid exception regardless of target architecture. (This
was a change affecting hppa, i386, sh4 and tricore.) However, this
was incorrect for i386, which documents in the SDM section 14.5.2
that for the 0 * Inf + NaN case that it will only raise the Invalid
exception when the input is an SNaN. (This is permitted by the IEEE
754-2008 specification, which documents that whether we raise Invalid
for 0 * Inf + QNaN is implementation defined.)
Adjust the softfloat pick_nan_muladd code to allow the target to
suppress the raising of Invalid for the inf * zero + NaN case (as an
extra flag orthogonal to its choice for when to use the default NaN),
and enable that for x86.
We do not revert here the behaviour change for hppa, sh4 or tricore:
* The sh4 manual is clear that it should signal Invalid
* The tricore manual is a bit vague but doesn't say it shouldn't
* The hppa manual doesn't talk about fused multiply-add corner
cases at all
Cc: qemu-stable@nongnu.org
Fixes: 8adcff4ae7 (""fpu: handle raising Invalid for infzero in pick_nan_muladd")
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Link: https://lore.kernel.org/r/20250116112536.4117889-2-peter.maydell@linaro.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Our float_flag_output_denormal exception flag is set when
the fpu code flushes an output denormal to zero. Rename
it to float_flag_output_denormal_flushed:
* this keeps it parallel with the flag for flushing
input denormals, which we just renamed
* it makes it clearer that it doesn't mean "set when
the output is a denormal"
Commit created with
for f in `git grep -l float_flag_output_denormal`; do sed -i -e 's/float_flag_output_denormal/float_flag_output_denormal_flushed/' $f; done
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20250124162836.2332150-21-peter.maydell@linaro.org
Our float_flag_input_denormal exception flag is set when the fpu code
flushes an input denormal to zero. This is what many guest
architectures (eg classic Arm behaviour) require, but it is not the
only donarmal-related reason we might want to set an exception flag.
The x86 behaviour (which we do not currently model correctly) wants
to see an exception flag when a denormal input is *not* flushed to
zero and is actually used in an arithmetic operation. Arm's FEAT_AFP
also wants these semantics.
Rename float_flag_input_denormal to float_flag_input_denormal_flushed
to make it clearer when it is set and to allow us to add a new
float_flag_input_denormal_used next to it for the x86/FEAT_AFP
semantics.
Commit created with
for f in `git grep -l float_flag_input_denormal`; do sed -i -e 's/float_flag_input_denormal/float_flag_input_denormal_flushed/' $f; done
and manual editing of softfloat-types.h and softfloat.c to clean
up the indentation afterwards and to fix a comment which wasn't
using the full name of the flag.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20250124162836.2332150-20-peter.maydell@linaro.org
Set the default NaN pattern explicitly, and remove the ifdef from
parts64_default_nan().
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20241202131347.498124-38-peter.maydell@linaro.org
Set the Float3NaNPropRule explicitly for i386. We had no
i386-specific behaviour in the old ifdef ladder, so we were using the
default "prefer a then b then c" fallback; this is actually the
correct per-the-spec handling for i386.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20241202131347.498124-25-peter.maydell@linaro.org
Set the FloatInfZeroNaNRule explicitly for the x86 target.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20241202131347.498124-12-peter.maydell@linaro.org
Set the NaN propagation rule explicitly for the float_status words
used in the x86 target.
This is a no-behaviour-change commit, so we retain the existing
behaviour of using the x87-style "prefer QNaN over SNaN, then prefer
the NaN with the larger significand" for MMX and SSE. This is
however not the documented hardware behaviour, so we leave a TODO
note about what we should be doing instead.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20241025141254.2141506-16-peter.maydell@linaro.org
xsave.flat checks that "executing the XSETBV instruction causes a general-
protection fault (#GP) if ECX = 0 and EAX[2:1] has the value 10b". QEMU allows
that option, so the test fails. Add the condition.
Cc: qemu-stable@nongnu.org
Fixes: 892544317fe ("target/i386: implement XSAVE and XRSTOR of AVX registers", 2022-10-18)
Reported-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
linux-user/i386: Fix allocation and alignment of fp state in signal frame
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Merge tag 'pull-lu-20240526' of https://gitlab.com/rth7680/qemu into staging
target/i386: Introduce X86Access and use for xsave and friends
linux-user/i386: Fix allocation and alignment of fp state in signal frame
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# gpg: Signature made Sun 26 May 2024 05:48:44 PM PDT
# gpg: using RSA key 7A481E78868B4DB6A85A05C064DF38E8AF7E215F
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# gpg: Good signature from "Richard Henderson <richard.henderson@linaro.org>" [ultimate]
* tag 'pull-lu-20240526' of https://gitlab.com/rth7680/qemu: (28 commits)
target/i386: Pass host pointer and size to cpu_x86_{xsave,xrstor}
target/i386: Pass host pointer and size to cpu_x86_{fxsave,fxrstor}
target/i386: Pass host pointer and size to cpu_x86_{fsave,frstor}
target/i386: Convert do_xrstor to X86Access
target/i386: Convert do_xsave to X86Access
linux-user/i386: Honor xfeatures in xrstor_sigcontext
linux-user/i386: Fix allocation and alignment of fp state
linux-user/i386: Return boolean success from xrstor_sigcontext
linux-user/i386: Return boolean success from restore_sigcontext
linux-user/i386: Fix -mregparm=3 for signal delivery
linux-user/i386: Split out struct target_fregs_state
linux-user/i386: Replace target_fpstate_fxsave with X86LegacyXSaveArea
linux-user/i386: Remove xfeatures from target_fpstate_fxsave
linux-user/i386: Drop xfeatures_size from sigcontext arithmetic
target/i386: Add {hw,sw}_reserved to X86LegacyXSaveArea
target/i386: Add rbfm argument to cpu_x86_{xsave,xrstor}
target/i386: Split out do_xsave_chk
target/i386: Convert do_xrstor_* to X86Access
target/i386: Convert do_xsave_* to X86Access
tagret/i386: Convert do_fxsave, do_fxrstor to X86Access
...
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
We have already validated the memory region in the course of
validating the signal frame. No need to do it again within
the helper function.
In addition, return failure when the header contains invalid
xstate_bv. The kernel handles this via exception handling
within XSTATE_OP within xrstor_from_user_sigframe.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
We have already validated the memory region in the course of
validating the signal frame. No need to do it again within
the helper function.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
We have already validated the memory region in the course of
validating the signal frame. No need to do it again within
the helper function.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
For now, continue to pass all 1's from signal.c.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This path is not required by user-only, and can in fact
be shared between xsave and xrstor.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The body of do_xrstor is now fully converted.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The body of do_xsave is now fully converted.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Move the alignment fault from do_* to helper_*, as it need
not apply to usage from within user-only signal handling.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Mark cc_op as clean and do not spill it at the end of the translation block.
Technically this is a tiny bit less efficient, but:
* it results in translations that are a tiny bit smaller
* for most of these instructions, it is not unlikely that they are close to
the end of the basic block, in which case cc_op would not be overwritten
* anyway the cost is probably dwarfed by that of computing flags.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The XRSTOR instruction ends calling tlb_flush(), declared
in "exec/exec-all.h".
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20231211212003.21686-13-philmd@linaro.org>
cpu_cc_compute_all() has an argument that is always equal to CC_OP for historical
reasons (dating back to commit a7812ae4123, "TCG variable type checking.", 2008-11-17,
which added the argument to helper_cc_compute_all). It does not make sense for the
argument to have any other value, so remove it and clean up some lines that are not
too long anymore.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
All these files access the CPU LD/ST API declared in "exec/cpu_ldst.h".
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230828221314.18435-4-philmd@linaro.org>
VROUND, FSTCW and STMXCSR all have to perform the same conversion from
x86 rounding modes to softfloat constants. Since the ISA is consistent
on the meaning of the two-bit rounding modes, extract the common code
into a wrapper for set_float_rounding_mode.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This adds another kind of weirdness when you thought you had seen it all:
an opcode byte that comes _after_ the address, not before. It's not
worth adding a new X86_SPECIAL_* constant for it, but it's actually
not unlike VCMP; so, forgive me for exploiting the similarity and just
deciding to dispatch to the right gen_helper_* call in a single code
generation function.
In fact, the old decoder had a bug where s->rip_offset should have
been set to 1 for 3DNow! instructions, and it's fixed now.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The new implementation of SSE will cover AVX from the get go, because
all the work for the helper functions is already done. We just need to
build them.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add a new hflag bit to determine whether AVX instructions are allowed
Signed-off-by: Paul Brook <paul@nowt.org>
Message-Id: <20220424220204.2493824-4-paul@nowt.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add support for saving/restoring extended save states when signals
are delivered. This allows using AVX, MPX or PKRU registers in
signal handlers.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Coverity warns that 14 << data32 may overflow with respect
to the target_ulong to which it is subsequently added.
We know this wasn't true because data32 is in [1,2],
but the suggested fix is perfectly fine.
Fixes: Coverity CID 1487135, 1487256
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Damien Hedde <damien.hedde@greensocs.com>
Message-Id: <20220401184635.327423-1-richard.henderson@linaro.org>
The instruction description says "It is loaded without rounding
errors." which implies we should have the widest rounding mode
possible.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/888
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220315121251.2280317-4-alex.bennee@linaro.org>
Update FCS:FIP and FDS:FDP according to the Intel Manual Vol.1 8.1.8.
Note that CPUID.(EAX=07H,ECX=0H):EBX[bit 13] is not implemented by
design in this patch and will be added along with TCG features flag
in a separate patch later.
Signed-off-by: Ziqiao Kong <ziqiaokong@gmail.com>
Message-Id: <20210530150112.74411-2-ziqiaokong@gmail.com>
[rth: Push FDS/FDP handling down into mod != 3 case; free last_addr.]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Do not call helper_fninit directly from helper_xrstor.
Do call the new helper from do_fsave.
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Given that TCG is now the only consumer of X86XSaveArea, move the
structure definition and associated offset declarations and checks to a
TCG specific header.
Signed-off-by: David Edmondson <david.edmondson@oracle.com>
Message-Id: <20210705104632.2902400-9-david.edmondson@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Use an enumeration instead of raw 32/64/80 values.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
create a separate tcg/sysemu/fpu_helper.c for the sysemu-only parts.
For user mode, some small #ifdefs remain in tcg/fpu_helper.c
which do not seem worth splitting into their own user-mode module.
Signed-off-by: Claudio Fontana <cfontana@suse.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210322132800.7470-16-cfontana@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The helper_* functions must use GETPC() to unwind from TCG.
The cpu_x86_* functions cannot, and directly calling the
helper_* functions is a bug. Split out new functions that
perform the work and can be used by both.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Claudio Fontana <cfontana@suse.de>
Tested-by: Claudio Fontana <cfontana@suse.de>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20210322132800.7470-4-cfontana@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Change the prefix from "helper" to "do". The former should be
reserved for those functions that are called from TCG; the latter
is in use within the file already for those functions that are
called from the helper functions, adding a "retaddr" argument.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Claudio Fontana <cfontana@suse.de>
Tested-by: Claudio Fontana <cfontana@suse.de>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20210322132800.7470-3-cfontana@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
