The current helper flags, TCG_CALL_CONST and TCG_CALL_PURE might be
confusing and doesn't provide enough granularity for some helpers (FP
helpers for example).
This patch changes them into the following helpers flags:
- TCG_CALL_NO_READ_GLOBALS means that the helper does not read globals,
either directly or via an exception. They will not be saved to their
canonical location before calling the helper.
- TCG_CALL_NO_WRITE_GLOBALS means that the helper does not modify any
globals. They will only be saved to their canonical locations before
calling helpers, but they won't be reloaded afterwise.
- TCG_CALL_NO_SIDE_EFFECTS means that the call to the function is
removed if the return value is not used.
It provides convenience flags, to avoid helper definitions longer than
80 characters. It also provides compatibility flags, and updates the
documentation.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Operations with side effects (in practice qemu_ld/st ops), only need to
synchronize globals to make sure the CPU state is consistent in case of
exception.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
The liveness analysis ensures that globals and temps are at the correct
state at a basic block end or with an op with side effects. Avoid
looping on all temps, this can be time consuming on targets with a lot
of globals. Keep an assert in debug mode.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Start with local temps in TEMP_VAL_MEM state, to make possible a later
check that all the temps are correctly saved back to memory.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Always mark dead input arguments as dead, even if the op is at the basic
block end. This will allow to check that all temps are correctly saved.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Now that the liveness analysis provides more information, rewrite
tcg_reg_alloc_mov(). This changes the behaviour about propagating
constants and memory accesses. We now take the assumption that once
a value is loaded into a register (from memory or from a constant),
it's better to keep it there than to reload it later. This assumption
is now always almost correct given that we are now sure the
corresponding temp is going to be used later (otherwise it would have
been synchronized and marked as dead already). The assumption is wrong
if one of the op after clobbers some registers including the one
of the holding the temp (this can be avoided by allocating clobbered
registers last, which is what most TCG target do), or in case of lack
of available register.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Now that the liveness analysis might mark some output temps as dead, call
temp_dead() if needed.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Rework the liveness analysis by tracking temps that need to go back to
memory in addition to dead temps tracking. This allows to mark output
arguments as "need sync", and to synchronize them back to memory as soon
as they are not written anymore. This way even arguments mapping to
globals can be marked as "dead", avoiding moves to a new register when
input and outputs are aliased.
In addition it means that registers are freed as soon as temps are not
used anymore, instead of waiting for a basic block end or an op with side
effects. This reduces register spilling especially on CPUs with few
registers, and spread the mov over all the TB, increasing the
performances on in-order CPUs.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Synchronize an output argument when requested by the liveness analysis.
This is needed so that the temp can be declared dead later.
For that, add a new op_sync_args table in which each bit tells if the
corresponding output argument needs to be synchronized with the memory.
Pass it to the tcg_reg_alloc_* functions, and honor this bit. We need to
synchronize the argument before marking it as dead, and we have to make
sure all the infos about the temp are correctly filled.
At the same time change some types from unsigned int to uint16_t when
passing op_dead_args.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Add a new function temp_sync() to synchronize the canonical location
of a temp with the value in the corresponding register, but without
freeing the associated register. Rewrite temp_save() to call
temp_sync() followed by temp_dead().
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Add a new function tcg_reg_sync() to synchronize the canonical location
of a temp with the value in the associated register, but without freeing
it. Rewrite tcg_reg_free() to first call tcg_reg_sync() and then to free
the register.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
A lot of code is duplicated to mark a temporary as dead. Replace it
by temp_dead(), which in addition marks the temp as saved in memory
for globals and local temps, instead of doing this a posteriori in
temp_save().
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Like add2, do operand ordering, constant folding, and dead operand
elimination. The latter happens about 15% of all mulu2 during an
x86_64 bios boot.
Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
When x86_64 guest is not in 64-bit mode, the high-part of the 64-bit
add is dead. When the host is 32-bit, we can simplify to 32-bit
arithmetic.
Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
GUEST_BASE support is now supported by all TCG backends, and is
now mandatory. Drop the now-pointless TCG_TARGET_HAS_GUEST_BASE
define (set by every backend) and the error if it is unset.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
The pointer entry 'temps' always refers to the array entry 'static_temps'.
Removing the pointer and renaming 'static_temps' to 'temps' reduces the
size of TCGContext (4 or 8 byte) and allows better code generation.
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 several cases that can be handled easier inside both
translators and code generators if we have out-of-band values
for conditions. It's easy enough to handle ALWAYS and NEVER in
the natural way inside the tcg middle-end.
Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Checking that we don't try for idx != [01] is trivial. Checking
that we don't issue more than one of any index requires a tad
more data and some ifdefs protecting that new variable.
Signed-off-by: Richard Henderson <rth@twiddle.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
* 'tcg-sparc' of git://repo.or.cz/qemu/rth:
tcg-sparc: Preserve branch destinations during retranslation
tcg-sparc: Fix and enable direct TB chaining.
tcg-sparc: Add %g/%o registers to alloc_order
tcg-sparc: Use defines for temporaries.
tcg-sparc: Mask shift immediates to avoid illegal insns.
tcg-sparc: Clean up cruft stemming from attempts to use global registers.
tcg-sparc: Change AREG0 in generated code to %i0.
tcg-sparc: Support GUEST_BASE.
tcg-sparc: Fix qemu_ld/st to handle 32-bit host.
tcg-sparc: Assume v9 cpu always, i.e. force v8plus in 32-bit mode.
tcg-sparc: Don't MAP_FIXED on top of the program
tcg-sparc: Fix ADDX opcode.
tcg-sparc: Hack in qemu_ld/st64 for 32-bit.
linux-user: Use memcpy in get_user/put_user.
The TCG targets no longer need individual implementations.
Since commit 6a18ae2d29,
'flags' is no longer used in tcg_target_get_call_iarg_regs_count.
The remaining tcg_target_get_call_iarg_regs_count is trivial and only
called once. Therefore the patch eliminates it completely.
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Commit 25c4d9cc changed all TCGOpcode enums to be available, so we don't
need to #ifdef #endif the one that are available only on some targets.
This makes the code easier to read.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Current code doesn't actually work in 32-bit mode at all. Since
no one really noticed, drop the complication of v7 and v8 cpus.
Eliminate the --sparc_cpu configure option and standardize macro
testing on TCG_TARGET_REG_BITS / HOST_LONG_BITS
Signed-off-by: Richard Henderson <rth@twiddle.net>
Implemented with setcond if the target does not provide
the optional opcode.
Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
set_label is effectively the end of a basic block, as no optimization
can be made accross it. It was treated as such in the liveness analysis
code, but as a special case.
Mark it with TCG_OPF_BB_END flag so that this information can be used
by other parts of the TCG code, and remove the special case in the liveness
analysis code.
Cc: Blue Swirl <blauwirbel@gmail.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Now that there are two passes of optimization (optimize.c, liveness)
there is no point of outputing the statistics of the liveness part
only. Update the code to take into account both optimizations.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Don't use global variables directly but via accessor functions. Rename globals.
Convert macros to functions, add GCC format attributes.
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
This allows us to actually supply a function name in softmmu builds;
gdb doesn't pick up the minimal symbol table otherwise. Also add a
bit of documentation and statically generate more of the ELF image.
Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
This allows us to generate unwind info for the dynamicly generated
code in the code_gen_buffer. Only i386 is converted at this point.
Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
Use stack based calling convention (GCC default) for interfacing with
generated code instead of register based convention (regparm(3)).
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
An attempt to allocate a large memory chunk after a small one resulted in
circular links in list of pools. It caused the same memory being
allocated twice for different arrays.
Now pools for large memory chunks are kept in separate list and are
freed during pool reset because current allocator can not reuse them.
Signed-off-by: Kirill Batuzov <batuzovk@ispras.ru>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
tcg_out_label is always called with a third argument of pointer type
which was casted to tcg_target_long.
These casts can be avoided by changing the prototype of tcg_out_label.
There was also a cast to long. For most hosts with
sizeof(long) == sizeof(tcg_target_long) == sizeof(void *) this did not
matter, but for w64 it was wrong. This is fixed now.
Cc: Blue Swirl <blauwirbel@gmail.com>
Cc: Richard Henderson <rth@twiddle.net>
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
The standard include files are already included in qemu-common.h.
malloc.h and alloca.h were needed for alloca() which was removed
from TCG code some years ago when switching from dyngen to TCG
(see commit 49516bc0d6).
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Including tcg_out_ld, tcg_out_st, tcg_out_mov, tcg_out_movi.
Signed-off-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Andreas Färber <afaerber@suse.de>
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Alexander Graf <agraf@suse.de>
tcg_op_defs was already a global array.
The tci disassembler also needs ARRAY_SIZE(tcg_op_defs),
so add a new global constant with this value.
Signed-off-by: Stefan Weil <sw@weilnetz.de>
These functions are defined in the tcg target specific file
tcg-target.c.
The forward declarations assert that every tcg target uses
the same function prototype.
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>
By always defining these symbols, we can eliminate a lot of ifdefs.
To allow this to be checked reliably, the semantics of the
TCG_TARGET_HAS_* macros must be changed from def/undef to true/false.
This allows even more ifdefs to be removed, converting them into
C if statements.
Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
This allows the simplification of the op_bits function from
tcg/optimize.c.
Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
Added file tcg/optimize.c to hold TCG optimizations. Function tcg_optimize
is called from tcg_gen_code_common. It calls other functions performing
specific optimizations. Stub for constant folding was added.
Signed-off-by: Kirill Batuzov <batuzovk@ispras.ru>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
Use stack instead of temp_buf array in CPUState for TCG temps.
On Sparc64, stack pointer is not aligned but there is a fixed bias of 2047,
so don't try to enforce alignment.
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
The code for stack allocation for call arguments is way too simplistic
to actually work on targets with non-trivial stack allocation policies,
e.g. ppc64. We've also already allocated TCG_STATIC_CALL_ARGS_SIZE worth
of stack for calls which should be well more than any helper needs.
Remove broken dynamic stack allocation code and replace it with an assert.
Should dynamic stack allocation ever be needed again, target specific
functions should be added.
Thanks to Richard Henderson for the analysis.
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
Based on a patch from Hans de Goede <hdegoede@redhat.com>
This warning is new in gcc 4.6.
Acked-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Christophe Fergeau <cfergeau@redhat.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
