I found with qemu 2.11.x or newer that I would get an illegal instruction
error running some Intel binaries on my ARM chromebook. On investigation,
I found it was quitting on memory barriers.
qemu instruction:
mb $0x31
was translating as:
0x604050cc: 5bf07ff5 blpl #0x600250a8
After patch it gives:
0x604050cc: f57ff05b dmb ish
In short, I found INSN_DMB_ISH (memory barrier for ARMv7) appeared to be
correct based on online docs, but due to some endian-related shenanigans it
had to be byte-swapped to suit qemu; it appears INSN_DMB_MCR (memory
barrier for ARMv6) also should be byte swapped (and this patch does so).
I have not checked for correctness of aarch64's barrier instruction.
Backports commit 3f814b803797c007abfe5c4041de754e01723031 from qemu
The code sequence we were generating was only good for unsigned
comparisons. For signed comparisions, use the sequence from gcc.
Fixes booting of ppc64 firmware, with a patch changing the code
sequence for ppc comparisons.
Backports commit 7170ac33135e6ecf89752d3949bcecf9b9766d1c from qemu
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.
Backports commit f46934df662182097dce07d57ec00f37e4d2abf1 from qemu
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.
Backports commit 95ede84f4de18747d03d79c148013cff99acd60b from qemu
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.
Backports commit 647ab96aaf5defeb138e48d610f7f633c587b40d from qemu
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.
Backports commit 659ef5cbb893872d25e9d95191cc23b16546c8a1 from qemu
Patch 85aa80813dd changed the IF emitting the TST instruction,
but failed to change the ?: converting CMP to CMPEQ, so the
result of the TST is ignored.
Backports commit ca671de8af96798e0f493378240034620a3a04ee from qemu
The new placement of the TB means that we can use one insn
to load the goto_tb destination directly from the TB.
Backports commit 308714e6bc945389c64faf1b9213e2c0d3f03391 from qemu
In theory this would re-enable usage of QEMU on an armv4 host.
Whether this is worthwhile is debatable -- we've been unconditionally
issuing the armv5t BX instruction in the prologue since 2011 without
complaint. Possibly we should simply require an armv6 host.
Backports commit 702a947484eb3e615183dafc93de590ab0679f60 from qemu
This will let us choose how to interpret a given constraint
depending on whether the opcode is 32- or 64-bit. Which will
let us share more constraint combinations between opcodes.
At the same time, change the interface to return the advanced
pointer instead of passing it in/out by reference.
Backports commit 069ea736b50b75fdec99c9b8cc603b97bd98419e from qemu
This will allow the target to tailor the constraints to the
auto-detected ISA extensions.
Backports commit f69d277ece43c42c7ab0144c2ff05ba740f6706b from qemu
This allows us to use this detection within the TCG_TARGET_HAS_*
macros, instead of requiring a function call into tcg-target.inc.c.
Backports commit 40b2ccb156534f5d5f1d110a6ce008d87ee10af1 from qemu
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.
Backports commit 85aa80813dd9f5c1f581c743e45678a3bee220f8 from qemu
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
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
Ensure direct jump patching in ARM is atomic by using
atomic_read()/atomic_set() for code patching.
Backports commit 7d14e0e2d661479985197203589c38840e1066df from qemu
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
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
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