The code which patches x86 jump instructions assumes it can do an
unaligned write of a uint32_t. This is actually safe on x86, but it's
still undefined behaviour. We have infrastructure for doing efficient
unaligned accesses which doesn't engage in undefined behaviour, so
use it.
This is technically fractionally less efficient, at least with gcc 4.6;
instead of one instruction:
7b2: 89 3e mov %edi,(%rsi)
we get an extra spurious store to the stack slot:
7b2: 89 7c 24 64 mov %edi,0x64(%rsp)
7b6: 89 3e mov %edi,(%rsi)
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
The ARM A64 decoder's worst case number of TCG ops per instruction
is 266 (for insn 0x4c800000, a post-indexed ST4 multiple-structures
store). Raise the MAX_OP_PER_INSTR define accordingly.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Message-id: 1394822294-14837-17-git-send-email-peter.maydell@linaro.org
There is a HOST_PAGE_ALIGN macro which makes sense for KVM accelerator
but it uses qemu_host_page_size/qemu_host_page_mask which initialized
for TCG only.
This moves qemu_host_page_size/qemu_host_page_mask initialization from
TCG's page_init() and adds a call for it from kvm_init().
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
phys_mem_alloc and its assigned values qemu_anon_ram_alloc and
legacy_s390_alloc must have identical argument lists.
legacy_s390_alloc uses the size parameter to call mmap, so size_t is
good enough for all of them.
This patch fixes compiler errors on i686 Linux hosts:
CC alpha-softmmu/exec.o
exec.c:752:51: error:
initialization from incompatible pointer type [-Werror]
exec.c: In function 'qemu_ram_alloc_from_ptr':
exec.c:1139:32: error:
comparison of distinct pointer types lacks a cast [-Werror]
exec.c: In function 'qemu_ram_remap':
exec.c:1283:21: error:
comparison of distinct pointer types lacks a cast [-Werror]
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-id: 1380481005-32399-1-git-send-email-sw@weilnetz.de
Signed-off-by: Anthony Liguori <aliguori@amazon.com>
A minimal update to use the new helpers with the return address argument.
Tested-by: Claudio Fontana <claudio.fontana@linaro.org>
Reviewed-by: Claudio Fontana <claudio.fontana@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Use the new helper_ret_*_mmu routines. Use a conditional call
to arrange for a tail-call from the store path, and to load the
return address for the helper for the load path.
Signed-off-by: Richard Henderson <rth@twiddle.net>
These use a 32-bit load-of-immediate to save a mflr+addi+mtlr sequence.
Tested with a Windows 98 guest (pretty much the most recent thing I
could run on my PPC machine) and kvm-unit-tests's sieve.flat. The
speed up for sieve.flat is as high as 10% for qemu-system-i386, 25%
(no kidding) for qemu-system-x86_64 on my PowerBook G4.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Make it a generic hook rather than a KVM hook. Less code and
ifdeffery.
Since the only user of the hook is old S390 KVM, there's hope we can
get rid of it some day.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Message-id: 1375276272-15988-5-git-send-email-armbru@redhat.com
Signed-off-by: Anthony Liguori <anthony@codemonkey.ws>
The _cmmu helpers can be moved to exec-all.h. The helpers that are
used from TCG will shortly need access to tcg_target_long so move
their declarations into tcg.h.
This requires minor include adjustments to all TCG backends.
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Always define GETRA; use __builtin_extract_return_addr, rather than
having a special case for s390. Split GETPC_ADJ out of GETPC; use 2
universally, rather than having a special case for arm.
Rename GETPC_LDST to GETRA_LDST to indicate that it does not
contain the GETPC_ADJ value. Likewise with GETPC_EXT to GETRA_EXT.
Perform the GETPC_ADJ adjustment inside helper_ret_ld/st. This will
allow backends to pass along the "true" return address rather than
the massaged GETPC value. In the meantime, double application of
GETPC_ADJ does not hurt, since the call insn in all ISAs is at least
4 bytes long.
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Indeed, remove it entirely and remove the is_tcg_gen_code check
from GETPC_EXT.
Fixes https://bugs.launchpad.net/qemu/+bug/1218098 wherein a call
to a "normal" helper function performed a sequence of tail calls
all the way into the memory helper functions, leading to a stack
frame in which the memory helper function appeared to be called
directly from tcg.
Signed-off-by: Richard Henderson <rth@twiddle.net>
Discontinue the jump-around-jump-to-jump scheme, trading it for a single
immediate move instruction. The two extra jumps always consume 7 bytes,
whereas the immediate move is either 5 or 7 bytes depending on where the
code_gen_buffer gets located.
Signed-off-by: Richard Henderson <rth@twiddle.net>
add preliminary support for TCG target aarch64.
Signed-off-by: Claudio Fontana <claudio.fontana@huawei.com>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 51A5C596.3090108@huawei.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Move the slow path out of line, as the TODO's mention.
This allows the fast path to be unconditional, which can
speed up the fast path as well, depending on the core.
Signed-off-by: Richard Henderson <rth@twiddle.net>
Explictly NULL it on CPU reset since it was located before breakpoints.
Change vapic_report_tpr_access() argument to CPUState. This also
resolves the use of void* for cpu.h independence.
Change vAPIC patch_instruction() argument to X86CPU.
Signed-off-by: Andreas Färber <afaerber@suse.de>
It's worth to clean-up translation blocks variables and move them
into one context as was suggested by Swirl.
Also if we use this context directly inside tcg_ctx, then it
speeds up code generation a bit.
Signed-off-by: Evgeny Voevodin <evgenyvoevodin@gmail.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
s390x-linux-user now also uses GETPC. Instead of adding it to the list of
targets which use GETPC, the macro is now defined unconditionally.
This avoids future build regressions like this one:
CC s390x-linux-user/target-s390x/int_helper.o
cc1: warnings being treated as errors
qemu/target-s390x/int_helper.c: In function ‘helper_divs32’:
qemu/target-s390x/int_helper.c:47: error: implicit declaration of function ‘GETPC’
qemu/target-s390x/int_helper.c:47: error: nested extern declaration of ‘GETPC’
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
Refactor common code around calls to cpu_restore_state().
tb_find_pc() has now no external users, make it static.
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
commit 5f7319cd introduced GETPC() usage for MIPS, which is currently
not defined when building with --enable-tcg-interpreter. Add MIPS to
the list of targets we selectively define GETPC() for.
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
mmu access looks something like:
<check tlb>
if miss goto slow_path
<fast path>
done:
...
; end of the TB
slow_path:
<pre process>
mr r3, r27 ; move areg0 to r3
; (r3 holds the first argument for all the PPC32 ABIs)
<call mmu_helper>
b $+8
.long done
<post process>
b done
On ppc32 <call mmu_helper> is:
(SysV and Darwin)
mmu_helper is most likely not within direct branching distance from
the call site, necessitating
a. moving 32 bit offset of mmu_helper into a GPR ; 8 bytes
b. moving GPR to CTR/LR ; 4 bytes
c. (finally) branching to CTR/LR ; 4 bytes
r3 setting - 4 bytes
call - 16 bytes
dummy jump over retaddr - 4 bytes
embedded retaddr - 4 bytes
Total overhead - 28 bytes
(PowerOpen (AIX))
a. moving 32 bit offset of mmu_helper's TOC into a GPR1 ; 8 bytes
b. loading 32 bit function pointer into GPR2 ; 4 bytes
c. moving GPR2 to CTR/LR ; 4 bytes
d. loading 32 bit small area pointer into R2 ; 4 bytes
e. (finally) branching to CTR/LR ; 4 bytes
r3 setting - 4 bytes
call - 24 bytes
dummy jump over retaddr - 4 bytes
embedded retaddr - 4 bytes
Total overhead - 36 bytes
Following is done to trim the code size of slow path sections:
In tcg_target_qemu_prologue trampolines are emitted that look like this:
trampoline:
mfspr r3, LR
addi r3, 4
mtspr LR, r3 ; fixup LR to point over embedded retaddr
mr r3, r27
<jump mmu_helper> ; tail call of sorts
And slow path becomes:
slow_path:
<pre process>
<call trampoline>
.long done
<post process>
b done
call - 4 bytes (trampoline is within code gen buffer
and most likely accessible via
direct branch)
embedded retaddr - 4 bytes
Total overhead - 8 bytes
In the end the icache pressure is decreased by 20/28 bytes at the cost
of an extra jump to trampoline and adjusting LR (to skip over embedded
retaddr) once inside.
Signed-off-by: malc <av1474@comtv.ru>
Add GETPC_EXT which is used by MMU helpers to selectively calculate the code
address of accessing guest memory when called from a qemu_ld/st optimized code
or a C function. Currently, it supports only i386 and x86-64 hosts.
Signed-off-by: Yeongkyoon Lee <yeongkyoon.lee@samsung.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.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>
It is used nowhere else, and the corresponding MAX_CODE_GEN_BUFFER_SIZE
also lives there.
Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
commit c28ae41 introduced GETPC() usage for sparc, which is currently
not defined when building with --enable-tcg-interpreter. Add sparc to
the list of targets we selectively define GETPC() for.
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Now that CONFIG_TCG_PASS_AREG0 is enabled for all targets,
remove dead code and support for !CONFIG_TCG_PASS_AREG0 case.
Remove dyngen-exec.h and all references to it. Although included by
hw/spapr_hcall.c, it does not seem to use it.
Remove unused HELPER_CFLAGS.
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
Reviewed-by: Richard Henderson <rth@twiddle.net>
DEF_HELPER_FLAGS_5 was added some time ago without adjusting
MAX_OPC_PARAM_IARGS.
Fixing the definition becomes more important as QEMU is using
an increasing number of helper functions called with 5 arguments.
Add also a comment to avoid future problems when DEF_HELPER_FLAGS_6
will be added.
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
There are no users left for previous exception handler returned from
cpu_set_debug_excp_handler. It should simplify code a little.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
If we execute linux-user code that does the following:
* A = mmap()
* execute code in A
* munmap(A)
* B = mmap(), but mmap returns the same address as A
* execute code in B
we end up executing a stale cached tb that contains translated code
from A, while we want new code from B.
This patch adds a TB flush for mmap'ed regions, before we return them,
avoiding the whole issue. It also adds a flush for munmap, so that we
don't execute stale TBs instead of getting a segfault.
Reported-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Riku Voipio <riku.voipio@linaro.org>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>