Commit Graph

180 Commits

Author SHA1 Message Date
Sergey Sorokin
1f00b27f17 tcg: Improve the alignment check infrastructure
Some architectures (e.g. ARMv8) need the address which is aligned
to a size more than the size of the memory access.
To support such check it's enough the current costless alignment
check implementation in QEMU, but we need to support
an alignment size specifying.

Signed-off-by: Sergey Sorokin <afarallax@yandex.ru>
Message-Id: <1466705806-679898-1-git-send-email-afarallax@yandex.ru>
Signed-off-by: Richard Henderson <rth@twiddle.net>
[rth: Assert in tcg_canonicalize_memop.  Leave get_alignment_bits
available for, though unused by, user-mode.  Retain logging difference
based on ALIGNED_ONLY.]
2016-07-05 20:50:13 -07:00
Richard Henderson
59d7c14eef tcg: Optimize spills of constants
While we can store constants via constrants on INDEX_op_st_i32 et al,
we weren't able to spill constants to backing store.

Add a new backend interface, tcg_out_sti, which may store the constant
(and is allowed to fail).  Rearrange the temp_* helpers so that we only
attempt to directly store a constant when the temp is becoming dead/free.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-07-05 20:50:13 -07:00
Sergey Fedorov
f309101c26 tcg: Clean up direct block chaining data fields
Briefly describe in a comment how direct block chaining is done. It
should help in understanding of the following data fields.

Rename some fields in TranslationBlock and TCGContext structures to
better reflect their purpose (dropping excessive 'tb_' prefix in
TranslationBlock but keeping it in TCGContext):
   tb_next_offset  =>  jmp_reset_offset
   tb_jmp_offset   =>  jmp_insn_offset
   tb_next         =>  jmp_target_addr
   jmp_next        =>  jmp_list_next
   jmp_first       =>  jmp_list_first

Avoid using a magic constant as an invalid offset which is used to
indicate that there's no n-th jump generated.

Signed-off-by: Sergey Fedorov <serge.fdrv@gmail.com>
Signed-off-by: Sergey Fedorov <sergey.fedorov@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-05-12 14:06:41 -10:00
Sergey Fedorov
0d07abf05e tcg/i386: Make direct jump patching thread-safe
Ensure direct jump patching in i386 is atomic by:
 * naturally aligning a location of direct jump address;
 * using atomic_read()/atomic_set() for code patching.

tcg_out_nopn() implementation:
Suggested-by: Richard Henderson <rth@twiddle.net>.

Signed-off-by: Sergey Fedorov <serge.fdrv@gmail.com>
Signed-off-by: Sergey Fedorov <sergey.fedorov@linaro.org>
Message-Id: <1461341333-19646-6-git-send-email-sergey.fedorov@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-05-12 14:06:41 -10:00
Aurelien Jarno
8d8fdbae01 tcg: check for CONFIG_DEBUG_TCG instead of NDEBUG
Check for CONFIG_DEBUG_TCG instead of NDEBUG, drop now useless code.

Cc: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Message-id: 1461228530-14852-2-git-send-email-aurelien@aurel32.net
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-04-21 15:43:20 +01:00
Aurelien Jarno
eabb7b91b3 tcg: use tcg_debug_assert instead of assert (fix performance regression)
The TCG code is quite performance sensitive, but at the same time can
also be quite tricky. That is why asserts that can be enabled with the
--enable-debug-tcg configure option.

This used to work the following way:

| #include "config.h"
|
| ...
|
| #if !defined(CONFIG_DEBUG_TCG) && !defined(NDEBUG)
| /* define it to suppress various consistency checks (faster) */
| #define NDEBUG
| #endif
|
| ...
|
| #include <assert.h>

Since commit 757e725b (tcg: Clean up includes) "config.h" as been
replaced by "qemu/osdep.h" which itself includes <assert.h>. As a
consequence the assertions are always enabled, even when using
--disable-debug-tcg, causing a performance regression, especially on
targets with many registers. For instance on qemu-system-ppc the
speed difference is about 15%.

tcg_debug_assert is controlled directly by CONFIG_DEBUG_TCG and already
uses in some places. This patch replaces all the calls to assert into
calss to tcg_debug_assert.

Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Message-id: 1461228530-14852-1-git-send-email-aurelien@aurel32.net
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-04-21 15:41:47 +01:00
Peter Maydell
c3b7f66800 tcg: Remove unnecessary osdep.h includes from tcg-target.inc.c
Commit 757e725b58 added a number of #include "qemu/osdep.h"
files to the tcg-target.c files (as they were named at the time).
These are unnecessary because these files are not standalone C
files, and the tcg/tcg.c file which includes them will have
already included osdep.h on their behalf. Remove the unneeded
include directives.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <1456238983-10160-4-git-send-email-peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-02-23 08:31:03 -08:00
Peter Maydell
ce15110981 tcg: Rename tcg-target.c to tcg-target.inc.c
Rename the per-architecture tcg-target.c files to tcg-target.inc.c.
This makes it clearer that they are not intended to be standalone
C files, but are instead #included into another source file.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <1456238983-10160-2-git-send-email-peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-02-23 08:30:38 -08:00
Peter Maydell
757e725b58 tcg: Clean up includes
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.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1453832250-766-16-git-send-email-peter.maydell@linaro.org
2016-01-29 15:07:23 +00:00
Aurelien Jarno
08b0b23be6 tcg/i386: omit a few REXW prefixes in softmmu code
When computing the TLB address we are likely to mask out the high
32-bits by using shr + and. We can use 32-bit instructions in that
case. This saves 2 bytes per TLB access.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Message-Id: <1437306632-20655-1-git-send-email-aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-09-02 14:24:10 -07:00
Laurent Vivier
b76f21a707 linux-user: remove useless macros GUEST_BASE and RESERVED_VA
As we have removed CONFIG_USE_GUEST_BASE, we always use a guest base
and the macros GUEST_BASE and RESERVED_VA become useless: replace
them by their values.

Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <1440420834-8388-1-git-send-email-laurent@vivier.eu>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-08-24 11:14:30 -07:00
Aurelien Jarno
8cc580f6a0 tcg/i386: use softmmu fast path for unaligned accesses
Softmmu unaligned load/stores currently goes through through the slow
path for two reasons:
  - to support unaligned access on host with strict alignement
  - to correctly handle accesses crossing pages

x86 is only concerned by the second reason. Unaligned accesses are
avoided by compilers, but are not uncommon. We therefore would like
to see them going through the fast path, if they don't cross pages.

For that we can use the fact that two adjacent TLB entries can't contain
the same page. Therefore accessing the TLB entry corresponding to the
first byte, but comparing its content to page address of the last byte
ensures that we don't cross pages. We can do this check without adding
more instructions in the TLB code (but increasing its length by one
byte) by using the LEA instruction to combine the existing move with the
size addition.

On an x86-64 host, this gives a 3% boot time improvement for a powerpc
guest and 4% for an x86-64 guest.

[rth: Tidied calculation of the offset mask]

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Message-Id: <1436467197-2183-1-git-send-email-aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-08-24 11:10:54 -07:00
Richard Henderson
609ad70562 tcg: Split trunc_shr_i32 opcode into extr[lh]_i64_i32
Rather than allow arbitrary shift+trunc, only concern ourselves
with low and high parts.  This is all that was being used anyway.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-08-24 11:10:54 -07:00
Aurelien Jarno
4f2331e5b6 tcg: implement real ext_i32_i64 and extu_i32_i64 ops
Implement real ext_i32_i64 and extu_i32_i64 ops. They ensure that a
32-bit value is always converted to a 64-bit value and not propagated
through the register allocator or the optimizer.

Cc: Andrzej Zaborowski <balrogg@gmail.com>
Cc: Alexander Graf <agraf@suse.de>
Cc: Blue Swirl <blauwirbel@gmail.com>
Cc: Stefan Weil <sw@weilnetz.de>
Acked-by: Claudio Fontana <claudio.fontana@huawei.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-08-24 11:10:54 -07:00
Aurelien Jarno
0632e555fc tcg: rename trunc_shr_i32 into trunc_shr_i64_i32
The op is sometimes named trunc_shr_i32 and sometimes trunc_shr_i64_i32,
and the name in the README doesn't match the name offered to the
frontends.

Always use the long name to make it clear it is a size changing op.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-08-24 11:10:54 -07:00
Richard Henderson
ee8ba9e4d8 tcg/i386: Extend addresses for 32-bit guests
Removing the ??? comment explaining why it (mostly) worked.

Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Message-Id: <1437081950-7206-2-git-send-email-rth@twiddle.net>
2015-07-23 15:09:04 -07:00
Richard Henderson
2b7ec66f02 tcg: Mask TCGMemOp appropriately for indexing
The addition of MO_AMASK means that places that used inverted masks
need to be changed to use positive masks, and places that failed to
mask the intended bits need updating.

Reviewed-by: Yongbok Kim <yongbok.kim@imgtec.com>
Tested-by: Yongbok Kim <yongbok.kim@imgtec.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-06-09 06:35:29 -07:00
Paolo Bonzini
006f8638c6 tcg: add TCG_TARGET_TLB_DISPLACEMENT_BITS
This will be used to size the TLB when more than 8 MMU modes are
used by the target.  Limitations come from the limited size of
the immediate fields (which sometimes, as in the case of Aarch64,
extend to instructions that shift the immediate).

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1424436345-37924-2-git-send-email-pbonzini@redhat.com>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-06-03 23:56:56 +02:00
Richard Henderson
3972ef6f83 tcg: Push merged memop+mmu_idx parameter to softmmu routines
The extra information is not yet used but it is now available.
This requires minor changes through all of the tcg backends.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-05-14 12:15:14 -07:00
Richard Henderson
59227d5d45 tcg: Merge memop and mmu_idx parameters to qemu_ld/st
At the tcg opcode level, not at the tcg-op.h generator level.
This requires minor changes through all of the tcg backends,
but none of the cpu translators.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-05-14 12:14:55 -07:00
Richard Henderson
bec1631100 tcg: Change generator-side labels to a pointer
This is less about improved type checking than enabling a
subsequent change to the representation of labels.

Acked-by: Claudio Fontana <claudio.fontana@huawei.com>
Tested-by: Claudio Fontana <claudio.fontana@huawei.com>
Cc: Andrzej Zaborowski <balrogg@gmail.com>
Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Cc: Blue Swirl <blauwirbel@gmail.com>
Cc: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-03-13 12:28:18 -07:00
Richard Henderson
42a268c241 tcg: Change translator-side labels to a pointer
This is improved type checking for the translators -- it's no longer
possible to accidentally swap arguments to the branch functions.

Note that the code generating backends still manipulate labels as int.

With notable exceptions, the scope of the change is just a few lines
for each target, so it's not worth building extra machinery to do this
change in per-target increments.

Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: Edgar E. Iglesias <edgar.iglesias@gmail.com>
Cc: Michael Walle <michael@walle.cc>
Cc: Leon Alrae <leon.alrae@imgtec.com>
Cc: Anthony Green <green@moxielogic.com>
Cc: Jia Liu <proljc@gmail.com>
Cc: Alexander Graf <agraf@suse.de>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Cc: Blue Swirl <blauwirbel@gmail.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Reviewed-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-03-13 12:28:18 -07:00
Richard Henderson
3d1b2ff62c tcg: Remove TCG_TARGET_HAS_new_ldst
Since all backends have been converted, remove the compatibility code.

Acked-by: Claudio Fontana <claudio.fontana@huawei.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-06-04 14:10:26 -07:00
Richard Henderson
0b91966730 tcg-i386: Fix win64 qemu store
The first non-register argument isn't placed at offset 0.

Cc: qemu-stable@nongnu.org
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-06-04 13:58:39 -07:00
Richard Henderson
e9a9a5b605 tcg-i386: Make debug_frame const
Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-05-28 09:33:55 -07:00
Richard Henderson
96d0ee7f09 tcg: Remove unreachable code in tcg_out_op and op_defs
The INDEX_op_call case has just been obsoleted; the mov and movi
cases have not been reachable for years.  Attempt to document this
both in each tcg_out_op switch, and via TCG_OPF_NOT_PRESENT.

Because of the TCG_OPF_NOT_PRESENT change, this must be done for
all targets in a single commit.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-05-12 11:13:13 -07:00
Richard Henderson
6bf3e99747 tcg-i386: Rename tcg_out_calli to tcg_out_call
Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-05-12 11:13:11 -07:00
Richard Henderson
f6bff89d06 tcg-i386: Define TCG_TARGET_INSN_UNIT_SIZE
And use tcg pointer differencing functions as appropriate.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-05-12 10:03:04 -07:00
Peter Maydell
5c53bb8121 tcg: Avoid undefined behaviour patching code at unaligned addresses
To avoid C undefined behaviour when patching generated code,
provide wrappers tcg_patch8/16/32/64 which use the usual memcpy
trick, and use them in the i386 backend.

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>
2014-05-12 10:03:04 -07:00
Richard Henderson
4bb7a41ed6 tcg: Add INDEX_op_trunc_shr_i32
Let the backend do something special for truncation.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-04-28 11:06:34 -07:00
Richard Henderson
02eb19d0ec tcg: Use HOST_WORDS_BIGENDIAN
Instead of rolling a local TCG_TARGET_WORDS_BIGENDIAN.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-04-18 16:57:37 -07:00
Richard Henderson
f6c6afc1d4 tcg: Add TCGType parameter to tcg_target_const_match
Most 64-bit targets need to be able to ignore the high bits
of a TCG_TYPE_I32 value.

Suggested-by: Stuart Brady <sdb@zubnet.me.uk>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-04-18 16:57:36 -07:00
Stefan Weil
ad5171dbd4 tcg: Fix warning (1 bit signed bitfield entry) and replace int by bool
Static code analyzers complain about signed bitfields with only a single
bit. is_ld is used as a boolean value, so make it bool.

ppc64 already used bool for the 2nd argument is_ld of the local function
add_qemu_ldst_label. Modify all other TCG targets to do follow this
example.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-04-18 16:57:36 -07:00
Peter Maydell
774d566cdb tcg/i386: Fix build for systems without working cpuid.h (MacOSX, Win32)
Win32 doesn't have a cpuid.h, and MacOSX may have one but without
the __cpuid() function we use, which means that commit 9d2eec20
broke the build for those platforms. Fix this by tightening up
our configure cpuid.h check to test that the functions we need
are present, and adding some missing #ifdef guards in
tcg/i386/tcg-target.c.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
2014-02-21 10:39:10 +00:00
Richard Henderson
6399ab3325 tcg/i386: Use SHLX/SHRX/SARX instructions
These three-operand shift instructions do not require the shift count
to be placed into ECX.  This reduces the number of mov insns required,
with the mere addition of a new register constraint.

Don't attempt to get rid of the matching constraint, as that's impossible
to manipulate with just a new constraint.  In addition, constant shifts
still need the matching constraint.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-02-17 10:12:29 -06:00
Richard Henderson
9d2eec202f tcg/i386: Use ANDN instruction
Note that the optimizer cannot simplify ANDC X,Y,C to AND X,Y,~C
so we must handle constants in the implementation of andc.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-02-17 10:12:29 -06:00
Richard Henderson
ecc7e84327 tcg/i386: Add tcg_out_vex_modrm
Prepare for emitting BMI insns which require VEX encoding.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-02-17 10:12:29 -06:00
Richard Henderson
a1b29c9ae0 tcg/i386: Move TCG_CT_CONST_* to tcg-target.c
These are not needed by users of tcg-target.h.  No need to recompile
when we adjust them.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-02-17 10:12:29 -06:00
Aurelien Jarno
2d23d5edb5 tcg/i386: cleanup useless #ifdef
TCG_TARGET_HAS_movcond_i32 is always defined to 1 in tcg-target.h, so
remove the corresponding #ifdef #endif sequence, left from a previous
refactoring.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-01-25 15:21:33 -08:00
Aurelien Jarno
085bb5bb64 tcg/i386: use movbe instruction in qemu_ldst routines
The movbe instruction has been added on some Intel Atom CPUs and on
recent Intel Haswell CPUs. It allows to load/store a value and at the
same time bswap it.

This patch detects the avaibility of this instruction and when available
use it in the qemu load/store routines in replacement of load/store +
bswap. Note that for 16-bit unsigned loads, movbe + movzw is basically the
same as movzw + bswap, so the patch doesn't touch this case.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
[RTH: Reduced the number of conditionals using "movop".]
Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-01-25 15:19:19 -08:00
Aurelien Jarno
2a1137753f tcg/i386: add support for three-byte opcodes
Add support for three-byte opcodes, starting with the 0x0f 0x38 prefix.
Use P_EXT38 as the new constant, and shift all other constants so that
P_EXT and P_EXT38 have neighbouring values.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
[RTH: Changed the name from P_EXT2 to P_EXT38.]
Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-01-25 14:12:45 -08:00
Aurelien Jarno
c9d78213b8 tcg/i386: remove hardcoded P_REXW value
P_REXW is defined has a constant at the beginning of i386/tcg-target.c,
but the corresponding bit is later used in a harcoded way, which defeat
the purpose of a constant.

Fix that by using a conditional expression operator instead of a shift.
On x86 this actually makes the code slightly smaller as GCC does in
practice (opc >> 8) & 8 instead of (opc & 0x800) >> 8 so the constants
are smaller to load.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-01-25 14:12:38 -08:00
Aurelien Jarno
8589467f94 tcg/i386: fix a comment
The comments apply to 8-bit stores, not 8-byte stores.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2013-12-21 16:41:56 +01:00
Richard Henderson
8221a267fd tcg-i386: Support new ldst opcodes
No support for helpers with non-default endianness yet,
but good enough to test the opcodes.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2013-10-12 16:19:19 -07:00
Richard Henderson
b3e2bc500f tcg-i386: Remove "cb" output restriction from qemu_st8 for i386
Once we form a combined qemu_st_i32 opcode, we won't be able to
have separate constraints based on size.  This one is fairly easy
to work around, since eax is available as a scratch register.

When storing variable data, this tends to merely exchange one mov
for another.  E.g.

-:  mov    %esi,%ecx
...
-:  mov    %cl,(%edx)
+:  mov    %esi,%eax
+:  mov    %al,(%edx)

Where we do have a regression is when storing constant data, in which
we may load the constant into edi, when only ecx/ebx ought to be used.

The proper way to recover this regression is to allow constants as
arguments to qemu_st_i32, so that we never load the constant data into
a register at all, must less the wrong register.  TBD.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2013-10-12 16:19:19 -07:00
Richard Henderson
7352ee546c tcg-i386: Tidy softmmu routines
Pass two TCGReg to tcg_out_tlb_load, rather than idx+args.

Move ldst_optimization routines just below tcg_out_tlb_load to avoid
the need for forward declarations.

Use TCGReg enum in preference to int where apprpriate.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2013-10-12 16:19:19 -07:00
Richard Henderson
37c5d0d5d1 tcg-i386: Use TCGMemOp within qemu_ldst routines
Step one in the transition, with constants passed down from tcg_out_op.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2013-10-12 16:19:19 -07:00
Richard Henderson
f713d6ad7b tcg: Add qemu_ld_st_i32/64
Step two in the transition, adding the new ldst opcodes.  Keep the old
opcodes around until all backends support the new opcodes.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2013-10-10 13:19:21 -07:00
Richard Henderson
9ecefc84dd tcg: Add tcg-be-ldst.h
Move TCGLabelQemuLdst and related stuff out of tcg.h.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2013-10-10 11:44:26 -07:00
Richard Henderson
6fb5874590 tcg-i386: Make use of zero-extended memory helper routines
For 8 and 16-bit unsigned loads, rely on the zero-extension
from the helper and use a smaller 32-bit move insn.

Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2013-09-02 09:08:31 -07:00