Commit Graph

1404 Commits

Author SHA1 Message Date
Richard Henderson
ebb90a005d tcg/i386: Extend TARGET_PAGE_MASK to the proper type
TARGET_PAGE_MASK, as defined, has type "int".  We need to extend
that to the proper target width before oring in an "unsigned".

Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-09-20 11:45:30 -07:00
Pranith Kumar
34f939218c tcg: Optimize fence instructions
This commit optimizes fence instructions.  Two optimizations are
currently implemented: (1) unnecessary duplicate fence instructions,
and (2) merging weaker fences into a stronger fence.

[rth: Merge tcg_optimize_mb back into tcg_optimize, so that we only
loop over the opcode stream once.  Merge "unrelated" weaker barriers
into one stronger barrier.]

Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Message-Id: <20160823134825.32578-1-bobby.prani@gmail.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-09-16 08:12:12 -07:00
Pranith Kumar
a1e69e2f81 tcg/tci: Add support for fence
Cc: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Message-Id: <20160714202026.9727-11-bobby.prani@gmail.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-09-16 08:12:12 -07:00
Pranith Kumar
f8f03b3707 tcg/sparc: Add support for fence
Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Message-Id: <20160714202026.9727-10-bobby.prani@gmail.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-09-16 08:12:11 -07:00
Pranith Kumar
c9314d610e tcg/s390: Add support for fence
Cc: Alexander Graf <agraf@suse.de>
Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Message-Id: <20160714202026.9727-9-bobby.prani@gmail.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-09-16 08:12:11 -07:00
Pranith Kumar
7b4af5ee8a tcg/ppc: Add support for fence
Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Message-Id: <20160714202026.9727-8-bobby.prani@gmail.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-09-16 08:12:11 -07:00
Pranith Kumar
6f0b99104a tcg/mips: Add support for fence
Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Message-Id: <20160714202026.9727-7-bobby.prani@gmail.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-09-16 08:12:11 -07:00
Pranith Kumar
5bbadbdfd6 tcg/ia64: Add support for fence
Cc: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Message-Id: <20160714202026.9727-6-bobby.prani@gmail.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-09-16 08:12:11 -07:00
Pranith Kumar
40f191ab82 tcg/arm: Add support for fence
Cc: Andrzej Zaborowski <balrogg@gmail.com>
Cc: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Message-Id: <20160714202026.9727-5-bobby.prani@gmail.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-09-16 08:12:11 -07:00
Pranith Kumar
c7a59c2a92 tcg/aarch64: Add support for fence
Cc: Claudio Fontana <claudio.fontana@gmail.com>
Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Message-Id: <20160714202026.9727-4-bobby.prani@gmail.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-09-16 08:12:11 -07:00
Pranith Kumar
a7d00d4eff tcg/i386: Add support for fence
Generate a 'lock orl $0,0(%esp)' instruction for ordering instead of
mfence which has similar ordering semantics.

Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Message-Id: <20160714202026.9727-3-bobby.prani@gmail.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-09-16 08:12:11 -07:00
Pranith Kumar
f65e19bc2c Introduce TCGOpcode for memory barrier
This commit introduces the TCGOpcode for memory barrier instruction.

This opcode takes an argument which is the type of memory barrier
which should be generated.

Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Message-Id: <20160714202026.9727-2-bobby.prani@gmail.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-09-16 08:12:11 -07:00
Richard Henderson
85aa80813d tcg: Support arbitrary size + alignment
Previously we allowed fully unaligned operations, but not operations
that are aligned but with less alignment than the operation size.

In addition, arm32, ia64, mips, and sparc had been omitted from the
previous overalignment patch, which would have led to that alignment
being enforced.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-09-16 08:12:06 -07:00
Ladi Prosek
d4b84d564e Remove unused function declarations
Unused function declarations were found using a simple gcc plugin and
manually verified by grepping the sources.

Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2016-09-15 15:32:22 +03:00
Thomas Huth
347519eb9d tcg: Remove duplicate header includes
host-utils.h and timer.h are included twice in tcg.c.
One time should be enough.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2016-09-15 15:32:22 +03:00
Thomas Huth
d41f3c3cc7 Remove remainders of HPPA backend
The HPPA backend has been removed by the following commit:

    802b508123
    tcg-hppa: Remove tcg backend

But some small pieces of the HPPA backend still survived until
today. Since we also do not have support for a HPPA target in
QEMU, we can nowadays safely remove the remaining HPPA parts
(like the disassembler code, or the detection of HPPA in the
configure script).

Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2016-09-15 15:32:22 +03:00
Richard Henderson
5a18407f55 tcg: Lower indirect registers in a separate pass
Rather than rely on recursion during the middle of register allocation,
lower indirect registers to loads and stores off the indirect base into
plain temps.

For an x86_64 host, with sufficient registers, this results in identical
code, modulo the actual register assignments.

For an i686 host, with insufficient registers, this means that temps can
be (temporarily) spilled to the stack in order to satisfy an allocation.
This as opposed to the possibility of not being able to spill, to allocate
a register for the indirect base, in order to perform a spill.

Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-08-05 21:44:40 +05:30
Richard Henderson
c0ef05b5e6 tcg: Require liveness analysis
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-08-05 21:44:40 +05:30
Richard Henderson
bdfb460ef7 tcg: Include liveness info in the dumps
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-08-05 21:44:40 +05:30
Richard Henderson
c70fbf0a99 tcg: Compress dead_temps and mem_temps into a single array
We only need two bits per temporary.  Fold the two bytes into one,
and reduce the memory and cachelines required during compilation.

Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-08-05 21:44:40 +05:30
Richard Henderson
bee158cb4d tcg: Fold life data into TCGOp
Reduce the size of other bitfields to make room.
This reduces the cache footprint of compilation.

Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-08-05 21:44:40 +05:30
Richard Henderson
dcb8e75870 tcg: Reorg TCGOp chaining
Instead of using -1 as end of chain, use 0, and link through the 0
entry as a fully circular double-linked list.

Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-08-05 21:44:18 +05:30
Richard Henderson
a1b3c48d2b tcg: Compress liveness data to 16 bits
This reduces both memory usage and per-insn cacheline usage
during code generation.

Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-08-05 21:44:17 +05:30
Paolo Bonzini
8bff06a0bb compiler: never omit assertions if using a static analysis tool
Assertions help both Coverity and the clang static analyzer avoid
false positives, but on the other hand both are confused when
the condition is compiled as (void)(x != FOO).  Always expand
assertion macros when using Coverity or clang, through a new
QEMU_STATIC_ANALYSIS preprocessor symbol.

This fixes a couple false positives in TCG.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-17 09:59:21 +02:00
Markus Armbruster
175de52487 Clean up decorations and whitespace around header guards
Cleaned up with scripts/clean-header-guards.pl.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Richard Henderson <rth@twiddle.net>
2016-07-12 16:20:46 +02:00
Markus Armbruster
14e54f8ecf tcg: Clean up tcg-target.h header guards
These use guard symbols like TCG_TARGET_$target.
scripts/clean-header-guards.pl doesn't like them because they don't
match their file name (they should, to make guard collisions less
likely).

Clean them up: use guard symbol $target_TCG_TARGET_H for
tcg/$target/tcg-target.h.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Richard Henderson <rth@twiddle.net>
2016-07-12 16:19:16 +02:00
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
Richard Henderson
120c1084ed tcg: Fix name for high-half register
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-07-05 20:50:12 -07:00
Lluís Vilanova
dcdaadb6ea trace: [all] Add "guest_mem_before" event
The event is described in "trace-events". Note that the "MO_AMASK" flag
is not traced, since it does not seem to affect the visible semantics of
instructions.

[s/inline inline/inline/ to fix clang build.
--Stefan]

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 146549350711.18437.726780393247474362.stgit@fimbulvetr.bsc.es
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-06-20 17:21:56 +01:00
Lluís Vilanova
7c2550432a exec: [tcg] Track which vCPU is performing translation and execution
Information is tracked inside the TCGContext structure, and later used
by tracing events with the 'tcg' and 'vcpu' properties.

The 'cpu' field is used to check tracing of translation-time
events ("*_trans"). The 'tcg_env' field is used to pass it to
execution-time events ("*_exec").

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Message-id: 146549350162.18437.3033661139638458143.stgit@fimbulvetr.bsc.es
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-06-20 15:30:01 +01:00
Paolo Bonzini
63c915526d cpu: move exec-all.h inclusion out of cpu.h
exec-all.h contains TCG-specific definitions.  It is not needed outside
TCG-specific files such as translate.c, exec.c or *helper.c.

One generic function had snuck into include/exec/exec-all.h; move it to
include/qom/cpu.h.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-19 16:42:29 +02:00
Paolo Bonzini
00f6da6a1a exec: extract exec/tb-context.h
TCG backends do not need most of exec-all.h; extract what they actually
need to a separate file or move it directly to tcg.h.  The next patch
will stop including exec-all.h from everywhere.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-19 16:42:29 +02:00
Paolo Bonzini
33c11879fd qemu-common: push cpu.h inclusion out of qemu-common.h
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-19 16:42:29 +02:00
Stefan Weil
cb8d4c8f54 Fix some typos found by codespell
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2016-05-18 15:04:27 +03:00
Sergey Fedorov
819af24b9c tcg: Clean up from 'next_tb'
The value returned from tcg_qemu_tb_exec() is the value passed to the
corresponding tcg_gen_exit_tb() at translation time of the last TB
attempted to execute. It is a little confusing to store it in a variable
named 'next_tb'. In fact, it is a combination of 4-byte aligned pointer
and additional information in its two least significant bits. Break it
down right away into two variables named 'last_tb' and 'tb_exit' which
are a pointer to the last TB attempted to execute and the TB exit
reason, correspondingly. This simplifies the code and improves its
readability.

Correct a misleading documentation comment for tcg_qemu_tb_exec() and
fix logging in cpu_tb_exec(). Also rename a misleading 'next_tb' in
another couple of places.

Signed-off-by: Sergey Fedorov <serge.fdrv@gmail.com>
Signed-off-by: Sergey Fedorov <sergey.fedorov@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-05-12 14:06:42 -10:00
Sergey Fedorov
90aa39a1cc tcg: Allow goto_tb to any target PC in user mode
In user mode, there's only a static address translation, TBs are always
invalidated properly and direct jumps are reset when mapping change.
Thus the destination address is always valid for direct jumps and
there's no need to restrict it to the pages the TB resides in.

Signed-off-by: Sergey Fedorov <serge.fdrv@gmail.com>
Signed-off-by: Sergey Fedorov <sergey.fedorov@linaro.org>
Cc: Riku Voipio <riku.voipio@iki.fi>
Cc: Blue Swirl <blauwirbel@gmail.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-05-12 14:06:42 -10:00
Sergey Fedorov
5b053a4a28 tcg: Clean up direct block chaining safety checks
We don't take care of direct jumps when address mapping changes. Thus we
must be sure to generate direct jumps so that they always keep valid
even if address mapping changes. Luckily, we can only allow to execute a
TB if it was generated from the pages which match with current mapping.

Document tcg_gen_goto_tb() declaration and note the reason for
destination PC limitations.

Some targets with variable length instructions allow TB to straddle a
page boundary. However, we make sure that both of TB pages match the
current address mapping when looking up TBs. So it is safe to do direct
jumps into the both pages. Correct the checks for some of those targets.

Given that, we can safely patch a TB which spans two pages. Remove the
unnecessary check in cpu_exec() and allow such TBs to be patched.

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
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
c82460a560 tcg/mips: Make direct jump patching thread-safe
Ensure direct jump patching in MIPS is atomic by using
atomic_read()/atomic_set() for code patching.

Signed-off-by: Sergey Fedorov <serge.fdrv@gmail.com>
Signed-off-by: Sergey Fedorov <sergey.fedorov@linaro.org>
Message-Id: <1461341333-19646-11-git-send-email-sergey.fedorov@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
[rth: Merged the deposit32 followup.]
[rth: Merged the following followup.]
Message-Id: <1462210518-26522-1-git-send-email-sergey.fedorov@linaro.org>
2016-05-12 14:06:41 -10:00
Sergey Fedorov
84f79fb7c6 tcg/sparc: Make direct jump patching thread-safe
Ensure direct jump patching in SPARC is atomic by using
atomic_read()/atomic_set() for code patching.

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>
Message-Id: <1461341333-19646-10-git-send-email-sergey.fedorov@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-05-12 14:06:41 -10:00
Sergey Fedorov
9e26911295 tcg/aarch64: Make direct jump patching thread-safe
Ensure direct jump patching in AArch64 is atomic by using
atomic_read()/atomic_set() for code patching.

Signed-off-by: Sergey Fedorov <serge.fdrv@gmail.com>
Signed-off-by: Sergey Fedorov <sergey.fedorov@linaro.org>
Message-Id: <1461341333-19646-9-git-send-email-sergey.fedorov@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-05-12 14:06:41 -10:00
Sergey Fedorov
7d14e0e2d6 tcg/arm: Make direct jump patching thread-safe
Ensure direct jump patching in ARM is atomic by using
atomic_read()/atomic_set() for code patching.

Signed-off-by: Sergey Fedorov <serge.fdrv@gmail.com>
Signed-off-by: Sergey Fedorov <sergey.fedorov@linaro.org>
Message-Id: <1461341333-19646-8-git-send-email-sergey.fedorov@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-05-12 14:06:41 -10:00
Sergey Fedorov
ed3d51ecd7 tcg/s390: Make direct jump patching thread-safe
Ensure direct jump patching in s390 is atomic by:
 * naturally aligning a location of direct jump address;
 * using atomic_read()/atomic_set() for code patching.

Signed-off-by: Sergey Fedorov <serge.fdrv@gmail.com>
Signed-off-by: Sergey Fedorov <sergey.fedorov@linaro.org>
Message-Id: <1461341333-19646-7-git-send-email-sergey.fedorov@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
Sergey Fedorov
399f164857 tcg/ppc: Make direct jump patching thread-safe
Ensure direct jump patching in PPC is atomic by:
 * limiting translation buffer size in 32-bit mode to be addressable by
   Branch I-form instruction;
 * using atomic_read()/atomic_set() for code patching.

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>
Message-Id: <1461341333-19646-5-git-send-email-sergey.fedorov@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-05-12 14:06:40 -10:00
Sergey Fedorov
76442a939e tci: Make direct jump patching thread-safe
Ensure direct jump patching in TCI is atomic by:
 * naturally aligning a location of direct jump address;
 * using atomic_read()/atomic_set() to load/store the address.

Signed-off-by: Sergey Fedorov <serge.fdrv@gmail.com>
Signed-off-by: Sergey Fedorov <sergey.fedorov@linaro.org>
Message-Id: <1461341333-19646-4-git-send-email-sergey.fedorov@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-05-12 14:06:40 -10:00
Edgar E. Iglesias
1d41478fd4 tcg: Add tcg_set_insn_param
Add tcg_set_insn_param as a mechanism to modify an insn
parameter after emiting the insn. This is useful for icount
and also for embedding fault information for a specific insn.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Message-id: 1461931684-1867-2-git-send-email-edgar.iglesias@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-05-12 13:22:26 +01:00
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