Pre-compute the function call layout for each helper at startup.
Drop TCG_CALL_DUMMY_ARG, as we no longer need to leave gaps
in the op->args[] array. This allows several places to stop
checking for NULL TCGTemp, to which TCG_CALL_DUMMY_ARG mapped.
For tcg_gen_callN, loop over the arguments once. Allocate the TCGOp
for the call early but delay emitting it, collecting arguments first.
This allows the argument processing loop to emit code for extensions
and have them sequenced before the call.
For tcg_reg_alloc_call, loop over the arguments in reverse order,
which allows stack slots to be filled first naturally.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
We have been allocating a worst case number of arguments
to support calls. Instead, allow the size to vary.
By default leave space for 4 args, to maximize reuse,
but allow calls to increase the number of args to 32.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
[PMD: Split patch in two]
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20221218211832.73312-3-philmd@linaro.org>
G_NORETURN was introduced in glib 2.68, fallback to G_GNUC_NORETURN in
glib-compat.
Note that this attribute must be placed before the function declaration
(bringing a bit of consistency in qemu codebase usage).
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Warner Losh <imp@bsdimp.com>
Message-Id: <20220420132624.2439741-20-marcandre.lureau@redhat.com>
The dh_alias redirect is intended to handle TCG types as distinguished
from C types. TCG does not distinguish signed int from unsigned int,
because they are the same size. However, we need to retain this
distinction for dh_typecode, lest we fail to extend abi types properly
for the host call parameters.
This bug was detected when running the 'arm' emulator on an s390
system. The s390 uses TCG_TARGET_EXTEND_ARGS which triggers code
in tcg_gen_callN to extend 32 bit values to 64 bits; the incorrect
sign data in the typemask for each argument caused the values to be
extended as unsigned values.
This simple program exhibits the problem:
static volatile int num = -9;
static volatile int den = -5;
int main(void)
{
int quo = num / den;
printf("num %d den %d quo %d\n", num, den, quo);
exit(0);
}
When run on the broken qemu, this results in:
num -9 den -5 quo 0
The correct result is:
num -9 den -5 quo 1
Fixes: 7319d83a73 ("tcg: Combine dh_is_64bit and dh_is_signed to dh_typecode")
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/876
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reported-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>
Tested-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>
Tested-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
We will shortly be interested in distinguishing pointers
from integers in the helper's declaration, as well as a
true void return. We currently have two parallel 1 bit
fields; merge them and expand to a 3 bit field.
Our current maximum is 7 helper arguments, plus the return
makes 8 * 3 = 24 bits used within the uint32_t typemask.
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Currently, helpers can only take up to 6 arguments. This patch adds the
capability for up to 7 arguments. I have tested it with the Hexagon port
that I am preparing for submission.
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <1580942510-2820-1-git-send-email-tsimpson@quicinc.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Especially when dealing with out-of-line gvec helpers, it is often
helpful to specify some vector pointers as constant. E.g. when
we have two inputs and one output, marking the two inputs as consts
pointers helps to avoid bugs.
Const pointers can be specified via "cptr", however behave in TCG just
like ordinary pointers. We can specify helpers like:
DEF_HELPER_FLAGS_4(gvec_vbperm, TCG_CALL_NO_RWG, void, ptr, cptr, cptr, i32)
void HELPER(gvec_vbperm)(void *v1, const void *v2, const void *v3,
uint32_t desc)
And make sure that here, only v1 will be written (as long as const is
not casted away, of course).
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190221093459.22547-1-david@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Remember which helpers have been marked noreturn.
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Depending on the host abi, float16, aka uint16_t, values are
passed and returned either zero-extended in the host register
or with garbage at the top of the host register.
The tcg code generator has so far been assuming garbage, as that
matches the x86 abi, but this is incorrect for other host abis.
Further, target/arm has so far been assuming zero-extended results,
so that it may store the 16-bit value into a 32-bit slot with the
high 16-bits already clear.
Rectify both problems by mapping "f16" in the helper definition
to uint32_t instead of (a typedef for) uint16_t. This forces
the host compiler to assume garbage in the upper 16 bits on input
and to zero-extend the result on output.
Cc: qemu-stable@nongnu.org
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Tested-by: Laurent Desnogues <laurent.desnogues@gmail.com>
Message-id: 20180522175629.24932-1-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This allows us to explicitly pass float16 to helpers rather than
assuming uint32_t and dealing with the result. Of course they will be
passed in i32 sized registers by default.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180227143852.11175-2-alex.bennee@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
We already handle this in the backends, and the lifetime datum
for the TCGOp is already large enough.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The GET and MAKE functions weren't really specific enough.
We now have a full complement of functions that convert exactly
between temporaries, arguments, tcgv pointers, and indices.
The target/sparc change is also a bug fix, which would have affected
a host that defines TCG_TARGET_HAS_extr[lh]_i64_i32, i.e. MIPS64.
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Transform TCGv_* to an "argument" or a temporary.
For now, an argument is simply the temporary index.
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Header guard symbols should match their file name to make guard
collisions less likely. Offenders found with
scripts/clean-header-guards.pl -vn.
Cleaned up with scripts/clean-header-guards.pl, followed by some
renaming of new guard symbols picked by the script to better ones.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Richard Henderson <rth@twiddle.net>
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.
NB: If this commit breaks compilation for your out-of-tree
patchseries or fork, then you need to make sure you add
#include "qemu/osdep.h" to any new .c files that you have.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Tidying the initialization of the args arrays at the same time.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Rather than special casing them, use the standard mechanisms
for tcg helper generation.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
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>
