qemu-e2k/tests/tcg
Paolo Bonzini e7bbb7cb71 target/i386: introduce flags writeback mechanism
ALU instructions can write to both memory and flags.  If the CC_SRC*
and CC_DST locations have been written already when a memory access
causes a fault, the value in CC_SRC* and CC_DST might be interpreted
with the wrong CC_OP (the one that is in effect before the instruction.

Besides just using the wrong result for the flags, something like
subtracting -1 can have disastrous effects if the current CC_OP is
CC_OP_EFLAGS: this is because QEMU does not expect bits outside the ALU
flags to be set in CC_SRC, and env->eflags can end up set to all-ones.
In the case of the attached testcase, this sets IOPL to 3 and would
cause an assertion failure if SUB is moved to the new decoder.

This mechanism is not really needed for BMI instructions, which can
only write to a register, but put it to use anyway for cleanliness.
In the case of BZHI, the code has to be modified slightly to ensure
that decode->cc_src is written, otherwise the new assertions trigger.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-12-29 22:04:30 +01:00
..
aarch64 target/arm: Handle overflow in calculation of next timer tick 2023-11-27 15:27:36 +00:00
alpha
arm
cris
hexagon
hppa
i386 target/i386: introduce flags writeback mechanism 2023-12-29 22:04:30 +01:00
loongarch64
m68k
minilib
mips
multiarch
nios2
openrisc
ppc
ppc64
ppc64le
riscv64
s390x
sh4
sparc64
tricore
x86_64
xtensa
xtensaeb
Makefile.target
README

This directory contains various interesting guest programs for
regression testing. Tests are either multi-arch, meaning they can be
built for all guest architectures that support linux-user executable,
or they are architecture specific.

CRIS
====
The testsuite for CRIS is in tests/tcg/cris.  You can run it
with "make test-cris".