Commit Graph

1648 Commits

Author SHA1 Message Date
Richard Henderson
ba2c747992 tcg/s390x: Use constant pool for prologue
Rather than have separate code only used for guest_base,
rely on a recent change to handle constant pool entries.

Cc: qemu-s390x@nongnu.org
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-11-03 09:33:45 +01:00
Richard Henderson
5b38ee3161 tcg: Allow constant pool entries in the prologue
Both ARMv6 and AArch64 currently may drop complex guest_base values
into the constant pool.  But generic code wasn't expecting that, and
the pool is not emitted.  Correct that.

Tested-by: Emilio G. Cota <cota@braap.org>
Tested-by: Laurent Desnogues <laurent.desnogues@gmail.com>
Reported-by: Laurent Desnogues <laurent.desnogues@gmail.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-11-03 09:33:45 +01:00
Richard Henderson
1c2adb958f tcg: Initialize cpu_env generically
This is identical for each target.  So, move the initialization to
common code.  Move the variable itself out of tcg_ctx and name it
cpu_env to minimize changes within targets.

This also means we can remove tcg_global_reg_new_{ptr,i32,i64},
since there are no longer global-register temps created by targets.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-24 13:53:42 -07:00
Emilio G. Cota
3468b59e18 tcg: enable multiple TCG contexts in softmmu
This enables parallel TCG code generation. However, we do not take
advantage of it yet since tb_lock is still held during tb_gen_code.

In user-mode we use a single TCG context; see the documentation
added to tcg_region_init for the rationale.

Note that targets do not need any conversion: targets initialize a
TCGContext (e.g. defining TCG globals), and after this initialization
has finished, the context is cloned by the vCPU threads, each of
them keeping a separate copy.

TCG threads claim one entry in tcg_ctxs[] by atomically increasing
n_tcg_ctxs. Do not be too annoyed by the subsequent atomic_read's
of that variable and tcg_ctxs; they are there just to play nice with
analysis tools such as thread sanitizer.

Note that we do not allocate an array of contexts (we allocate
an array of pointers instead) because when tcg_context_init
is called, we do not know yet how many contexts we'll use since
the bool behind qemu_tcg_mttcg_enabled() isn't set yet.

Previous patches folded some TCG globals into TCGContext. The non-const
globals remaining are only set at init time, i.e. before the TCG
threads are spawned. Here is a list of these set-at-init-time globals
under tcg/:

Only written by tcg_context_init:
- indirect_reg_alloc_order
- tcg_op_defs
Only written by tcg_target_init (called from tcg_context_init):
- tcg_target_available_regs
- tcg_target_call_clobber_regs
- arm: arm_arch, use_idiv_instructions
- i386: have_cmov, have_bmi1, have_bmi2, have_lzcnt,
        have_movbe, have_popcnt
- mips: use_movnz_instructions, use_mips32_instructions,
        use_mips32r2_instructions, got_sigill (tcg_target_detect_isa)
- ppc: have_isa_2_06, have_isa_3_00, tb_ret_addr
- s390: tb_ret_addr, s390_facilities
- sparc: qemu_ld_trampoline, qemu_st_trampoline (build_trampolines),
         use_vis3_instructions

Only written by tcg_prologue_init:
- 'struct jit_code_entry one_entry'
- aarch64: tb_ret_addr
- arm: tb_ret_addr
- i386: tb_ret_addr, guest_base_flags
- ia64: tb_ret_addr
- mips: tb_ret_addr, bswap32_addr, bswap32u_addr, bswap64_addr

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-24 13:53:42 -07:00
Emilio G. Cota
e8feb96fcc tcg: introduce regions to split code_gen_buffer
This is groundwork for supporting multiple TCG contexts.

The naive solution here is to split code_gen_buffer statically
among the TCG threads; this however results in poor utilization
if translation needs are different across TCG threads.

What we do here is to add an extra layer of indirection, assigning
regions that act just like pages do in virtual memory allocation.
(BTW if you are wondering about the chosen naming, I did not want
to use blocks or pages because those are already heavily used in QEMU).

We use a global lock to serialize allocations as well as statistics
reporting (we now export the size of the used code_gen_buffer with
tcg_code_size()). Note that for the allocator we could just use
a counter and atomic_inc; however, that would complicate the gathering
of tcg_code_size()-like stats. So given that the region operations are
not a fast path, a lock seems the most reasonable choice.

The effectiveness of this approach is clear after seeing some numbers.
I used the bootup+shutdown of debian-arm with '-tb-size 80' as a benchmark.
Note that I'm evaluating this after enabling per-thread TCG (which
is done by a subsequent commit).

* -smp 1, 1 region (entire buffer):
    qemu: flush code_size=83885014 nb_tbs=154739 avg_tb_size=357
    qemu: flush code_size=83884902 nb_tbs=153136 avg_tb_size=363
    qemu: flush code_size=83885014 nb_tbs=152777 avg_tb_size=364
    qemu: flush code_size=83884950 nb_tbs=150057 avg_tb_size=373
    qemu: flush code_size=83884998 nb_tbs=150234 avg_tb_size=373
    qemu: flush code_size=83885014 nb_tbs=154009 avg_tb_size=360
    qemu: flush code_size=83885014 nb_tbs=151007 avg_tb_size=370
    qemu: flush code_size=83885014 nb_tbs=151816 avg_tb_size=367

That is, 8 flushes.

* -smp 8, 32 regions (80/32 MB per region) [i.e. this patch]:

    qemu: flush code_size=76328008 nb_tbs=141040 avg_tb_size=356
    qemu: flush code_size=75366534 nb_tbs=138000 avg_tb_size=361
    qemu: flush code_size=76864546 nb_tbs=140653 avg_tb_size=361
    qemu: flush code_size=76309084 nb_tbs=135945 avg_tb_size=375
    qemu: flush code_size=74581856 nb_tbs=132909 avg_tb_size=375
    qemu: flush code_size=73927256 nb_tbs=135616 avg_tb_size=360
    qemu: flush code_size=78629426 nb_tbs=142896 avg_tb_size=365
    qemu: flush code_size=76667052 nb_tbs=138508 avg_tb_size=368

Again, 8 flushes. Note how buffer utilization is not 100%, but it
is close. Smaller region sizes would yield higher utilization,
but we want region allocation to be rare (it acquires a lock), so
we do not want to go too small.

* -smp 8, static partitioning of 8 regions (10 MB per region):
    qemu: flush code_size=21936504 nb_tbs=40570 avg_tb_size=354
    qemu: flush code_size=11472174 nb_tbs=20633 avg_tb_size=370
    qemu: flush code_size=11603976 nb_tbs=21059 avg_tb_size=365
    qemu: flush code_size=23254872 nb_tbs=41243 avg_tb_size=377
    qemu: flush code_size=28289496 nb_tbs=52057 avg_tb_size=358
    qemu: flush code_size=43605160 nb_tbs=78896 avg_tb_size=367
    qemu: flush code_size=45166552 nb_tbs=82158 avg_tb_size=364
    qemu: flush code_size=63289640 nb_tbs=116494 avg_tb_size=358
    qemu: flush code_size=51389960 nb_tbs=93937 avg_tb_size=362
    qemu: flush code_size=59665928 nb_tbs=107063 avg_tb_size=372
    qemu: flush code_size=38380824 nb_tbs=68597 avg_tb_size=374
    qemu: flush code_size=44884568 nb_tbs=79901 avg_tb_size=376
    qemu: flush code_size=50782632 nb_tbs=90681 avg_tb_size=374
    qemu: flush code_size=39848888 nb_tbs=71433 avg_tb_size=372
    qemu: flush code_size=64708840 nb_tbs=119052 avg_tb_size=359
    qemu: flush code_size=49830008 nb_tbs=90992 avg_tb_size=362
    qemu: flush code_size=68372408 nb_tbs=123442 avg_tb_size=368
    qemu: flush code_size=33555560 nb_tbs=59514 avg_tb_size=378
    qemu: flush code_size=44748344 nb_tbs=80974 avg_tb_size=367
    qemu: flush code_size=37104248 nb_tbs=67609 avg_tb_size=364

That is, 20 flushes. Note how a static partitioning approach uses
the code buffer poorly, leading to many unnecessary flushes.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-24 13:53:42 -07:00
Emilio G. Cota
34184b0718 tcg: allocate optimizer temps with tcg_malloc
Groundwork for supporting multiple TCG contexts.

While at it, also allocate temps_used directly as a bitmap of the
required size, instead of using a bitmap of TCG_MAX_TEMPS via
TCGTempSet.

Performance-wise we lose about 1.12% in a translation-heavy workload
such as booting+shutting down debian-arm:

Performance counter stats for 'taskset -c 0 arm-softmmu/qemu-system-arm \
	-machine type=virt -nographic -smp 1 -m 4096 \
	-netdev user,id=unet,hostfwd=tcp::2222-:22 \
	-device virtio-net-device,netdev=unet \
	-drive file=die-on-boot.qcow2,id=myblock,index=0,if=none \
	-device virtio-blk-device,drive=myblock \
	-kernel kernel.img -append console=ttyAMA0 root=/dev/vda1 \
	-name arm,debug-threads=on -smp 1' (10 runs):

             exec time (s)  Relative slowdown wrt original (%)
---------------------------------------------------------------
 original     20.213321616                                  0.
 tcg_malloc   20.441130078                           1.1270214
 TCGContext   20.477846517                           1.3086662
 g_malloc     20.780527895                           2.8061013

The other two alternatives shown in the table are:
- TCGContext: embed temps[TCG_MAX_TEMPS] and TCGTempSet used_temps
  in TCGContext. This is simple enough but it isn't faster than using
  tcg_malloc; moreover, it wastes memory.
- g_malloc: allocate/deallocate both temps and used_temps every time
  tcg_optimize is executed.

Suggested-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-24 13:53:42 -07:00
Emilio G. Cota
c3fac1138e tcg: distribute profiling counters across TCGContext's
This is groundwork for supporting multiple TCG contexts.

To avoid scalability issues when profiling info is enabled, this patch
makes the profiling info counters distributed via the following changes:

1) Consolidate profile info into its own struct, TCGProfile, which
   TCGContext also includes. Note that tcg_table_op_count is brought
   into TCGProfile after dropping the tcg_ prefix.
2) Iterate over the TCG contexts in the system to obtain the total counts.

This change also requires updating the accessors to TCGProfile fields to
use atomic_read/set whenever there may be conflicting accesses (as defined
in C11) to them.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-24 13:53:42 -07:00
Emilio G. Cota
df2cce2968 tcg: introduce **tcg_ctxs to keep track of all TCGContext's
Groundwork for supporting multiple TCG contexts.

Note that having n_tcg_ctxs is unnecessary. However, it is
convenient to have it, since it will simplify iterating over the
array: we'll have just a for loop instead of having to iterate
over a NULL-terminated array (which would require n+1 elems)
or having to check with ifdef's for usermode/softmmu.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-24 13:53:42 -07:00
Emilio G. Cota
26689780f8 gen-icount: fold exitreq_label into TCGContext
Groundwork for supporting multiple TCG contexts.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-24 13:53:42 -07:00
Emilio G. Cota
b1311c4acf tcg: define tcg_init_ctx and make tcg_ctx a pointer
Groundwork for supporting multiple TCG contexts.

The core of this patch is this change to tcg/tcg.h:

> -extern TCGContext tcg_ctx;
> +extern TCGContext tcg_init_ctx;
> +extern TCGContext *tcg_ctx;

Note that for now we set *tcg_ctx to whatever TCGContext is passed
to tcg_context_init -- in this case &tcg_init_ctx.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-24 13:53:42 -07:00
Emilio G. Cota
44ded3d048 tcg: take tb_ctx out of TCGContext
Groundwork for supporting multiple TCG contexts.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-24 13:53:42 -07:00
Emilio G. Cota
e82d5a2460 tcg: check CF_PARALLEL instead of parallel_cpus
Thereby decoupling the resulting translated code from the current state
of the system.

The tb->cflags field is not passed to tcg generation functions. So
we add a field to TCGContext, storing there a copy of tb->cflags.

Most architectures have <= 32 registers, which results in a 4-byte hole
in TCGContext. Use this hole for the new field.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-24 13:53:42 -07:00
Emilio G. Cota
4e2ca83e71 tcg: define CF_PARALLEL and use it for TB hashing along with CF_COUNT_MASK
This will enable us to decouple code translation from the value
of parallel_cpus at any given time. It will also help us minimize
TB flushes when generating code via EXCP_ATOMIC.

Note that the declaration of parallel_cpus is brought to exec-all.h
to be able to define there the "curr_cflags" inline.

Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-24 13:53:41 -07:00
Richard Henderson
e89b28a635 tcg: Use offsets not indices for TCGv_*
Using the offset of a temporary, relative to TCGContext, rather than
its index means that we don't use 0.  That leaves offset 0 free for
a NULL representation without having to leave index 0 unused.

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>
2017-10-24 13:53:36 -07:00
Richard Henderson
11f4e8f8bf tcg: Remove TCGV_EQUAL*
When we used structures for TCGv_*, we needed a macro in order to
perform a comparison.  Now that we use pointers, this is just clutter.

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>
2017-10-24 21:50:15 +02:00
Richard Henderson
dc41aa7d34 tcg: Remove GET_TCGV_* and MAKE_TCGV_*
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>
2017-10-24 21:49:30 +02:00
Richard Henderson
085272b35e tcg: Introduce temp_tcgv_{i32,i64,ptr}
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>
2017-10-24 21:48:59 +02:00
Richard Henderson
ae8b75dc6e tcg: Introduce tcgv_{i32,i64,ptr}_{arg,temp}
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>
2017-10-24 21:47:46 +02:00
Richard Henderson
960c50e077 tcg: Push tcg_ctx into tcg_gen_callN
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>
2017-10-24 21:47:29 +02:00
Richard Henderson
b7e8b17a77 tcg: Push tcg_ctx into generator functions
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>
2017-10-24 21:45:07 +02:00
Richard Henderson
6349039d0b tcg: Use per-temp state data in optimize
While we're touching many of the lines anyway, adjust the naming
of the functions to better distinguish when "TCGArg" vs "TCGTemp"
should be used.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-10-24 21:45:07 +02:00
Richard Henderson
54534d7cfd tcg: Remove unused TCG_CALL_DUMMY_TCGV
Reviewed-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-10-24 21:45:07 +02:00
Richard Henderson
2272e4a791 tcg: Change temp_allocate_frame arg to TCGTemp
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-10-24 21:44:52 +02:00
Richard Henderson
ac3b88911e tcg: Avoid loops against variable bounds
Copy s->nb_globals or s->nb_temps to a local variable for the purposes
of iteration.  This should allow the compiler to use low-overhead
looping constructs on some hosts.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-10-24 21:44:34 +02:00
Richard Henderson
b83eabeac0 tcg: Use per-temp state data in liveness
This avoids having to allocate external memory for each temporary.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-10-24 21:44:34 +02:00
Richard Henderson
1807f4c400 tcg: Introduce temp_arg, export temp_idx
At the same time, drop the TCGContext argument and use tcg_ctx instead.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-10-24 21:44:12 +02:00
Richard Henderson
c6c7d84df8 tcg: Return NULL temp for TCG_CALL_DUMMY_ARG
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-10-24 21:44:02 +02:00
Richard Henderson
fa477d2547 tcg: Add temp_global bit to TCGTemp
This avoids needing to test the index of a temp against nb_globals.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-10-24 21:43:50 +02:00
Richard Henderson
434391390b tcg: Introduce arg_temp
Reviewed-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-10-24 21:43:36 +02:00
Richard Henderson
dd18629201 tcg: Propagate TCGOp down to allocators
Reviewed-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-10-24 21:34:47 +02:00
Richard Henderson
efee3746fa tcg: Propagate args to op->args in tcg.c
Reviewed-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-10-24 21:34:47 +02:00
Richard Henderson
acd937019b tcg: Propagate args to op->args in optimizer
Reviewed-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-10-24 21:34:47 +02:00
Richard Henderson
75e8b9b7aa tcg: Merge opcode arguments into TCGOp
Rather than have a separate buffer of 10*max_ops entries,
give each opcode 10 entries.  The result is actually a bit
smaller and should have slightly more cache locality.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-10-24 21:34:47 +02:00
Jiang Biao
8df8d529ed tcg/mips: delete commented out extern keyword.
Delete commented out extern keyword on link_error().

Signed-off-by: Jiang Biao <jiang.biao2@zte.com.cn>
Message-Id: <1506762042-32145-1-git-send-email-jiang.biao2@zte.com.cn>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-10 09:45:01 -07:00
Emilio G. Cota
a505785cd2 tcg: define TCG_HIGHWATER
Will come in handy very soon.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-10 09:45:00 -07:00
Emilio G. Cota
619205fd1f tcg: take .helpers out of TCGContext
Groundwork for supporting multiple TCG contexts.

The hash table becomes read-only after it is filled in,
so we can save space by keeping just a global pointer to it.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-10 07:37:10 -07:00
Emilio G. Cota
5e75150cdf tci: move tci_regs to tcg_qemu_tb_exec's stack
Groundwork for supporting multiple TCG contexts.

Compile-tested for all targets on an x86_64 host.

Suggested-by: Richard Henderson <rth@twiddle.net>
Acked-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-10 07:37:10 -07:00
Emilio G. Cota
e7e168f413 exec-all: extract tb->tc_* into a separate struct tc_tb
In preparation for adding tc.size to be able to keep track of
TB's using the binary search tree implementation from glib.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-10 07:37:10 -07:00
Emilio G. Cota
7f11636dbe tcg: remove addr argument from lookup_tb_ptr
It is unlikely that we will ever want to call this helper passing
an argument other than the current PC. So just remove the argument,
and use the pc we already get from cpu_get_tb_cpu_state.

This change paves the way to having a common "tb_lookup" function.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-10 07:37:10 -07:00
Emilio G. Cota
d453ec7825 tcg/mips: constify tcg_target_callee_save_regs
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-10 07:37:10 -07:00
Emilio G. Cota
e268f4c036 tcg/i386: constify tcg_target_callee_save_regs
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-10 07:37:10 -07:00
Richard Henderson
89b2e37e65 tcg/mips: Fully convert tcg_target_op_def
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-09-17 06:52:19 -07:00
Richard Henderson
9be44a16c2 tcg/sparc: Fully convert tcg_target_op_def
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-09-17 06:52:19 -07:00
Richard Henderson
6cb3658a04 tcg/ppc: Fully convert tcg_target_op_def
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-09-17 06:52:19 -07:00
Richard Henderson
7536b82d28 tcg/arm: Fully convert tcg_target_op_def
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-09-17 06:52:19 -07:00
Richard Henderson
1897cc2eb8 tcg/aarch64: Fully convert tcg_target_op_def
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-09-17 06:52:19 -07:00
Richard Henderson
80a8b9a910 tcg: Fix types in tcg_regset_{set,reset}_reg
There was a potential problem here with an ILP32 host
with 64 host registers.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-09-17 06:52:19 -07:00
Richard Henderson
f46934df66 tcg: Remove tcg_regset_set32
It's not even clear what the interface REG and VAL32 were supposed to mean.
All uses had REG = 0 and VAL32 was the bitset assigned to the destination.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-09-17 06:52:19 -07:00
Richard Henderson
07ddf036fa tcg: Remove tcg_regset_{or,and,andnot,not}
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-09-17 06:52:19 -07:00
Richard Henderson
d21369f5fb tcg: Remove tcg_regset_set
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-09-17 06:52:19 -07:00
Richard Henderson
ccb1bb66ea tcg: Remove tcg_regset_clear
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-09-17 06:52:19 -07:00
Richard Henderson
be0f34b584 tcg: Add tcg_op_supported
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-09-17 06:52:19 -07:00
Philippe Mathieu-Daudé
61a3f8f6c0 accel/tcg: move tcg-runtime to accel/tcg/
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20170911213328.9701-4-f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-09-17 06:52:19 -07:00
Philippe Mathieu-Daudé
ba026602a6 tcg/ppc: disable atomic write check on ppc32
This fixes building for ppc64 on ppc32 (changed in 5964fca8a1):

tcg/ppc/tcg-target.inc.c: In function 'tb_target_set_jmp_target':
include/qemu/compiler.h:86:30: error: static assertion failed: \
  "not expecting: sizeof(*(uint64_t *)jmp_addr) > ATOMIC_REG_SIZE"
	QEMU_BUILD_BUG_ON(sizeof(*ptr) > ATOMIC_REG_SIZE); \
	^
tcg/ppc/tcg-target.inc.c:1377:9: note: in expansion of macro 'atomic_set'
	atomic_set((uint64_t *)jmp_addr, pair);
	^

Suggested-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20170911204936.5020-1-f4bug@amsat.org>
[rth: Added commentary requested by pmm.]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-09-17 06:52:19 -07:00
Philippe Mathieu-Daudé
04ef33052c tcg/tci: do not use ldst label (never implemented)
changed in 659ef5cbb8, this fixes building with --enable-tcg-interpreter:

/home/travis/build/qemu/qemu/tcg/tcg.c:116:14: error: ‘tcg_out_ldst_finalize’ used but never defined [-Werror]
 static bool tcg_out_ldst_finalize(TCGContext *s);
              ^

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20170911022839.23231-1-f4bug@amsat.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-09-11 19:24:05 +01:00
Richard Henderson
53c89efd02 tcg/ppc: Use constant pool for movi
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-07 11:57:35 -07:00
Richard Henderson
77bfc7c0b4 tcg/ppc: Look for shifted constants
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-07 11:57:35 -07:00
Richard Henderson
5964fca8a1 tcg/ppc: Change TCG_REG_RA to TCG_REG_TB
At this point the conversion is a wash.  Loading of TB+ofs is
smaller, but the actual return address from exit_tb is larger.
There are a few more insns required to transition between TBs.

But the expectation is that accesses to the constant pool will
on the whole be smaller.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-07 11:57:35 -07:00
Richard Henderson
afe74dbd6a tcg/arm: Use constant pool for call
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-07 11:57:35 -07:00
Richard Henderson
880ad9626c tcg/arm: Use constant pool for movi
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-07 11:57:35 -07:00
Richard Henderson
2a8ab93c6b tcg/arm: Extract INSN_NOP
We'll want this for tcg_out_nop_fill.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-07 11:57:35 -07:00
Richard Henderson
1507061637 tcg/arm: Code rearrangement
Move constants before all of the functions.
Move tcg_out_<format> functions before all
of the others.  No functional change.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-07 11:57:35 -07:00
Richard Henderson
95ede84f4d tcg/arm: Tighten tlb indexing offset test
We are not going to use ldrd for loading the comparator
for 32-bit guests, so don't limit cmp_off to 8 bits then.
This eliminates one insn in the tlb load for some guests.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-07 11:57:35 -07:00
Richard Henderson
647ab96aaf tcg/arm: Improve tlb load for armv7
Use UBFX to avoid limitation on CPU_TLB_BITS.  Since we're dropping
the initial shift, we need to replace the page masking.  We can use
MOVW+BIC to do this without shifting.  The result is the same size
as the armv6 path with one less conditional instruction.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-07 11:57:35 -07:00
Richard Henderson
e9823b4c33 tcg/sparc: Use constant pool for movi
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-07 11:57:35 -07:00
Richard Henderson
ab20bdc116 tcg/sparc: Introduce TCG_REG_TB
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-07 11:57:35 -07:00
Richard Henderson
55129955e9 tcg/aarch64: Use constant pool for movi
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-07 11:57:35 -07:00
Richard Henderson
a534bb15f3 tcg/s390: Use constant pool for cmpi
Also use CHI/CGHI for 16-bit signed constants.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-07 11:57:35 -07:00
Richard Henderson
5bf67a9217 tcg/s390: Use constant pool for xori
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-07 11:57:35 -07:00
Richard Henderson
4046d9ca04 tcg/s390: Use constant pool for ori
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-07 11:57:35 -07:00
Richard Henderson
bdcd5d1926 tcg/s390: Use constant pool for andi
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-07 11:57:35 -07:00
Richard Henderson
28eef8aaec tcg/s390: Use constant pool for movi
Split out maybe_out_small_movi for use with other operations
that want to add to the constant pool.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-07 11:57:35 -07:00
Richard Henderson
e692a3492d tcg/s390: Fix sign of patch_reloc addend
We were passing in -2 instead of +2, but then ignoring
the actual contents of addend in the calculation.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-07 11:57:35 -07:00
Richard Henderson
829e1376d9 tcg/s390: Introduce TCG_REG_TB
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-07 11:57:35 -07:00
Richard Henderson
4e45f23943 tcg/i386: Store out-of-range call targets in constant pool
Already it saves 2 bytes per call, but also the constant pool
entry may well be shared across multiple calls.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-07 11:57:35 -07:00
Richard Henderson
57a269469d tcg: Infrastructure for managing constant pools
A new shared header tcg-pool.inc.c adds new_pool_label,
for registering a tcg_target_ulong to be emitted after
the generated code, plus relocation data to install a
pointer to the data.

A new pointer is added to the TCGContext, so that we
dump the constant pool as data, not code.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-07 11:57:35 -07:00
Richard Henderson
659ef5cbb8 tcg: Rearrange ldst label tracking
Dispense with TCGBackendData, as it has never been used for more than
holding a single pointer.  Use a define in the cpu/tcg-target.h to
signal requirement for TCGLabelQemuLdst, so that we can drop the no-op
tcg-be-null.h stubs.  Rename tcg-be-ldst.h to tcg-ldst.inc.c.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-07 11:57:35 -07:00
Richard Henderson
a858339336 tcg: Move USE_DIRECT_JUMP discriminator to tcg/cpu/tcg-target.h
Replace the USE_DIRECT_JUMP ifdef with a TCG_TARGET_HAS_direct_jump
boolean test.  Replace the tb_set_jmp_target1 ifdef with an unconditional
function tb_target_set_jmp_target.

While we're touching all backends, add a parameter for tb->tc_ptr;
we're going to need it shortly for some backends.

Move tb_set_jmp_target and tb_add_jump from exec-all.h to cpu-exec.c.

This opens the possibility for TCG_TARGET_HAS_direct_jump to be
a runtime decision -- based on host cpu capabilities, the size of
code_gen_buffer, or a future debugging switch.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-07 11:57:34 -07:00
Richard Henderson
cda4a338c4 tcg/tci: Add TCG_TARGET_DEFAULT_MO
Missed being added as part of 71650df7b0.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-09-07 18:57:34 +01:00
Richard Henderson
4609190b5f tcg/s390: Use slbgr for setcond le and leu
Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 07:24:46 -07:00
Richard Henderson
7af525af01 tcg/s390: Use load-on-condition-2 facility
This allows LOAD HALFWORD IMMEDIATE ON CONDITION,
eliminating one insn in some common cases.

Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 07:24:41 -07:00
Richard Henderson
c2097136ad tcg/s390: Use distinct-operands facility
This allows using a 3-operand insn form for some arithmetic,
logicals and shifts.

Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 07:24:38 -07:00
Richard Henderson
e42349cbd6 tcg/s390: Merge ori+xori facilities check to tcg_target_op_def
Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 07:24:35 -07:00
Richard Henderson
ba18b07dc6 tcg/s390: Merge add2i facilities check to tcg_target_op_def
Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 07:24:33 -07:00
Richard Henderson
a8f0269e9e tcg/s390: Merge muli facilities check to tcg_target_op_def
Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 07:24:31 -07:00
Richard Henderson
07952d9570 tcg/s390: Merge cmpi facilities check to tcg_target_op_def
Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 07:24:28 -07:00
Richard Henderson
9b5500b697 tcg/s390: Fully convert tcg_target_op_def
Use a switch instead of searching a table.

Acked-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-09-06 07:22:24 -07:00
Pranith Kumar
b32dc3370a tcg: Implement implicit ordering semantics
Currently, we cannot use mttcg for running strong memory model guests
on weak memory model hosts due to missing ordering semantics.

We implicitly generate fence instructions for stronger guests if an
ordering mismatch is detected. We generate fences only for the orders
for which fence instructions are necessary, for example a fence is not
necessary between a store and a subsequent load on x86 since its
absence in the guest binary tells that ordering need not be
ensured. Also note that if we find multiple subsequent fence
instructions in the generated IR, we combine them in the TCG
optimization pass.

This patch allows us to boot an x86 guest on ARM64 hosts using mttcg.

Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Message-Id: <20170829063313.10237-4-bobby.prani@gmail.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-09-05 13:41:46 -07:00
Pranith Kumar
71650df7b0 tcg: Add tcg target default memory ordering
Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Message-Id: <20170829063313.10237-3-bobby.prani@gmail.com>
[rth: Dropped ia64 hunk]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-09-05 12:56:40 -07:00
Richard Henderson
a46c1244a0 tcg: Remove support for ia64 as host
We threatened to remove ia64 as host in v2.9.0.  Its time has now come.

There are still some usages of defined(__ia64__) throughout the source
code that would be triggered if one were to enable TCI on an ia64 host.
Leave those alone for now.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-09-05 12:39:25 -07:00
Richard Henderson
13aaef678e tcg: Increase minimum alignment from tcg_malloc to 8
For a 64-bit ILP32 host, aligning to sizeof(long) is not enough.
Guess the minimum for any host is 8, as that covers uint64_t.
Qemu doesn't use a host long double or host vectors, except in
extremely limited circumstances.

Fixes a bus error for a sparc v8plus host.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-08-03 11:00:30 -07:00
Richard Henderson
ca671de8af tcg/arm: Fix runtime overalignment test
Patch 85aa80813d changed the IF emitting the TST instruction,
but failed to change the ?: converting CMP to CMPEQ, so the
result of the TST is ignored.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-08-03 10:56:44 -07:00
Philippe Mathieu-Daudé
b208ac07ea docs: fix broken paths to docs/devel/atomics.txt
With the move of some docs/ to docs/devel/ on ac06724a71,
a couple of references were not updated.

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2017-07-31 13:12:47 +03:00
Richard Henderson
5dd8990841 util: Introduce include/qemu/cpuid.h
Clang 3.9 passes the CONFIG_AVX2_OPT configure test.  However, the
supplied <cpuid.h> does not contain the bit_AVX2 define that we use
when detecting whether the routine can be enabled.

Introduce a qemu-specific header that uses the compiler's definition
of __cpuid et al, but supplies any missing bit_* definitions needed.
This avoids introducing any extra ifdefs to util/bufferiszero.c, and
allows quite a few to be removed from tcg/i386/tcg-target.inc.c.

Signed-off-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20170719044018.18063-1-rth@twiddle.net
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-07-24 12:42:55 +01:00
Philippe Mathieu-Daudé
797ed66d29 tcg/tci: enable bswap16_i64
Altough correctly implemented, bswap16_i64() never got tested/executed so the
safety TODO() statement was never removed.

Since it got now tested the TODO() can be removed.

while running Alex Bennée's image aarch64-linux-3.15rc2-buildroot.img:

Trace 0x7fa1904b0890 [0: ffffffc00036cd04]
----------------
IN:
0xffffffc00036cd24:  5ac00694      rev16 w20, w20

OP:
 ---- ffffffc00036cd24 0000000000000000 0000000000000000
 ext32u_i64 tmp3,x20
 ext16u_i64 tmp2,tmp3
 bswap16_i64 x20,tmp2
 movi_i64 tmp4,$0x10
 shr_i64 tmp2,tmp3,tmp4
 ext16u_i64 tmp2,tmp2
 bswap16_i64 tmp2,tmp2
 deposit_i64 x20,x20,tmp2,$0x10,$0x10

Linking TBs 0x7fa1904b0890 [ffffffc00036cd04] index 0 -> 0x7fa1904b0aa0 [ffffffc00036cd24]
Trace 0x7fa1904b0aa0 [0: ffffffc00036cd24]
TODO qemu/tci.c:1049: tcg_qemu_tb_exec()
qemu/tci.c:1049: tcg fatal error
Aborted

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Jaroslaw Pelczar <j.pelczar@samsung.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Message-Id: <20170718045540.16322-11-f4bug@amsat.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-07-19 14:45:16 -07:00
Jiang Biao
4df9cac57f tcg/mips: reserve a register for the guest_base.
Reserve a register for the guest_base using ppc code for reference.
By doing so, we do not have to recompute it for every memory load.

Signed-off-by: Jiang Biao <jiang.biao2@zte.com.cn>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Message-Id: <1499677934-2249-1-git-send-email-jiang.biao2@zte.com.cn>
2017-07-19 14:45:15 -07:00
Lluís Vilanova
61a67f71dd exec: [tcg] Use different TBs according to the vCPU's dynamic tracing state
Every vCPU now uses a separate set of TBs for each set of dynamic
tracing event state values. Each set of TBs can be used by any number of
vCPUs to maximize TB reuse when vCPUs have the same tracing state.

This feature is later used by tracetool to optimize tracing of guest
code events.

The maximum number of TB sets is defined as 2^E, where E is the number
of events that have the 'vcpu' property (their state is stored in
CPUState->trace_dstate).

For this to work, a change on the dynamic tracing state of a vCPU will
force it to flush its virtual TB cache (which is only indexed by
address), and fall back to the physical TB cache (which now contains the
vCPU's dynamic tracing state as part of the hashing function).

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-id: 149915775266.6295.10060144081246467690.stgit@frigg.lan
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-07-17 13:11:05 +01:00
Jiang Biao
8b8d768f19 tcg/mips: Bugfix for crash when running program with qemu-i386.
When running a helloworld program with qemu-i386 in linux-user
mode on Loongson 3A3000, it will crash. This patch fix the bug.

Signed-off-by: Jiang Biao <jiang.biao2@zte.com.cn>
Message-Id: <1499669979-25904-1-git-send-email-jiang.biao2@zte.com.cn>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-07-09 21:11:38 -10:00
Pranith Kumar
2acee8b2b5 tcg/aarch64: Enable indirect jump path using LDR (literal)
This patch enables the indirect jump path using an LDR (literal)
instruction. It will be interesting to test and see which performs
better among the two paths.

CC: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Message-Id: <20170630143614.31059-3-bobby.prani@gmail.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-07-09 21:10:23 -10:00
Pranith Kumar
b68686bd4b tcg/aarch64: Use ADRP+ADD to compute target address
We use ADRP+ADD to compute the target address for goto_tb. This patch
introduces the NOP instruction which is used to align the above
instruction pair so that we can use one atomic instruction to patch
the destination offsets.

CC: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Message-Id: <20170630143614.31059-2-bobby.prani@gmail.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-07-09 21:10:23 -10:00