Commit graph

7 commits

Author SHA1 Message Date
Richard Henderson 23586e2674
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.

Backports commit 59d7c14eeff8d2ad7f61aed86ce5a176113bc153 from qemu
2018-02-25 01:45:29 -05:00
Sergey Fedorov e60c24cecf
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.

Backports commit f309101c26b59641fc1aa8fb2a98a5441cdaea03 from qemu
2018-02-23 21:28:19 -05:00
Sergey Fedorov a45f8cb49d
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.

Backports commit 9e269112953be4d670cb0d25042bd6546fcf3e45 from qemu
2018-02-23 21:28:18 -05:00
Aurelien Jarno 6060ab6596
tcg: check for CONFIG_DEBUG_TCG instead of NDEBUG
Check for CONFIG_DEBUG_TCG instead of NDEBUG, drop now useless code.

Backports commit 8d8fdbae010aa75a23f0307172e81034125aba6e from qemu
2018-02-23 13:55:21 -05:00
Aurelien Jarno 355ed7cd08
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Since commit 757e725b (tcg: Clean up includes) "config.h" as been
replaced by "qemu/osdep.h" which itself includes 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.

Backports commit eabb7b91b36b202b4dac2df2d59d698e3aff197a from qemu
2018-02-23 13:52:13 -05:00
Peter Maydell 764c2d09e5
tcg: Remove unnecessary osdep.h includes from tcg-target.inc.c
Commit 757e725b58c57d 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.

Backports commit c3b7f66800fbf9f47fddbcf2e2cd30ea932e0aae from qemu
2018-02-20 20:41:00 -05:00
Peter Maydell 7784a25470
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.

Backports commit ce151109813e2770fd3cee2f37bfa2cdd01a12b9 from qemu
2018-02-20 20:39:57 -05:00
Renamed from qemu/tcg/aarch64/tcg-target.c (Browse further)