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2017-06-19tcg: allocate TB structs before the corresponding translated codeEmilio G. Cota1-0/+20
Allocating an arbitrarily-sized array of tbs results in either (a) a lot of memory wasted or (b) unnecessary flushes of the code cache when we run out of TB structs in the array. An obvious solution would be to just malloc a TB struct when needed, and keep the TB array as an array of pointers (recall that tb_find_pc() needs the TB array to run in O(log n)). Perhaps a better solution, which is implemented in this patch, is to allocate TB's right before the translated code they describe. This results in some memory waste due to padding to have code and TBs in separate cache lines--for instance, I measured 4.7% of padding in the used portion of code_gen_buffer when booting aarch64 Linux on a host with 64-byte cache lines. However, it can allow for optimizations in some host architectures, since TCG backends could safely assume that the TB and the corresponding translated code are very close to each other in memory. See this message by rth for a detailed explanation: https://lists.gnu.org/archive/html/qemu-devel/2017-03/msg05172.html Subject: Re: GSoC 2017 Proposal: TCG performance enhancements Message-ID: <1e67644b-4b30-887e-d329-1848e94c9484@twiddle.net> Suggested-by: Richard Henderson <rth@twiddle.net> Reviewed-by: Pranith Kumar <bobby.prani@gmail.com> Signed-off-by: Emilio G. Cota <cota@braap.org> Message-Id: <1496790745-314-3-git-send-email-cota@braap.org> [rth: Simplify the arithmetic in tcg_tb_alloc] Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-06-05tcg: Introduce goto_ptr opcode and tcg_gen_lookup_and_goto_ptrEmilio G. Cota1-0/+5
Instead of exporting goto_ptr directly to TCG frontends, export tcg_gen_lookup_and_goto_ptr(), which calls goto_ptr with the pointer returned by the lookup_tb_ptr() helper. This is the only use case we have for goto_ptr and lookup_tb_ptr, so having this function is very convenient. Furthermore, it trivially allows us to avoid calling the lookup helper if goto_ptr is not implemented by the backend. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Emilio G. Cota <cota@braap.org> Message-Id: <1493263764-18657-2-git-send-email-cota@braap.org> Message-Id: <1493263764-18657-3-git-send-email-cota@braap.org> Message-Id: <1493263764-18657-4-git-send-email-cota@braap.org> Message-Id: <1493263764-18657-5-git-send-email-cota@braap.org> [rth: Squashed 4 related commits.] Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-01-10tcg: Allow an operand to be matching or a constantRichard Henderson1-31/+32
This allows an output operand to match an input operand only when the input operand needs a register. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-01-10tcg: Pass the opcode width to target_parse_constraintRichard Henderson1-4/+8
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. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-01-10tcg: Transition flat op_defs array to a target callbackRichard Henderson1-58/+28
This will allow the target to tailor the constraints to the auto-detected ISA extensions. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <rth@twiddle.net>
2017-01-10tcg: Add markup for output requires new registerRichard Henderson1-12/+22
This is the same concept as, and same markup as, the early clobber markup in gcc. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-11-01log: Add locking to large logging blocksRichard Henderson1-0/+8
Reuse the existing locking provided by stdio to keep in_asm, cpu, op, op_opt, op_ind, and out_asm as contiguous blocks. While it isn't possible to interleave e.g. in_asm or op_opt logs because of the TB lock protecting all code generation, it is possible to interleave cpu logs, or to interleave a cpu dump with an out_asm dump. For mingw32, we appear to have no viable solution for this. The locking functions are not properly exported from the system runtime library. Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-10-24tcg: try sti when moving a constant into a dead memory tempPaolo Bonzini1-29/+27
This comes from free from unifying tcg_reg_alloc_mov and tcg_reg_alloc_movi's handling of TEMP_VAL_CONST. It triggers often on moves to cc_dst, such as the following translation of "sub $0x3c,%esp": before: after: subl $0x3c,%ebp subl $0x3c,%ebp movl %ebp,0x10(%r14) movl %ebp,0x10(%r14) movl $0x3c,%ebx movl $0x3c,0x2c(%r14) movl %ebx,0x2c(%r14) Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <1473945360-13663-1-git-send-email-pbonzini@redhat.com> Reviewed-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-15tcg: Remove duplicate header includesThomas Huth1-2/+0
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>
2016-08-05tcg: Lower indirect registers in a separate passRichard Henderson1-53/+253
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>
2016-08-05tcg: Require liveness analysisRichard Henderson1-21/+0
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-08-05tcg: Include liveness info in the dumpsRichard Henderson1-21/+47
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-08-05tcg: Compress dead_temps and mem_temps into a single arrayRichard Henderson1-59/+60
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>
2016-08-05tcg: Fold life data into TCGOpRichard Henderson1-6/+3
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>
2016-08-05tcg: Reorg TCGOp chainingRichard Henderson1-20/+15
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>
2016-08-05tcg: Compress liveness data to 16 bitsRichard Henderson1-36/+22
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>
2016-07-05tcg: Improve the alignment check infrastructureSergey Sorokin1-8/+18
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.]
2016-07-05tcg: Optimize spills of constantsRichard Henderson1-74/+91
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>
2016-07-05tcg: Fix name for high-half registerRichard Henderson1-1/+1
Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-05-19cpu: move exec-all.h inclusion out of cpu.hPaolo Bonzini1-0/+5
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>
2016-04-21tcg: check for CONFIG_DEBUG_TCG instead of NDEBUGAurelien Jarno1-7/+2
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>
2016-04-21tcg: use tcg_debug_assert instead of assert (fix performance regression)Aurelien Jarno1-18/+18
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>
2016-03-22qemu-log: dfilter-ise exec, out_asm, op and opt_opAlex Bennée1-2/+4
This ensures the code generation debug code will honour -dfilter if set. For the "exec" tracing I've added a new inline macro for efficiency's sake. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Aurelien Jarno <aurelien@aureL32.net> Reviewed-by: Richard Henderson <rth@twiddle.net> Message-Id: <1458052224-9316-8-git-send-email-alex.bennee@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22tcg: pass down TranslationBlock to tcg_code_genAlex Bennée1-3/+3
My later debugging patches need access to the origin PC which is held in the TranslationBlock structure. Pass down the whole structure as it also holds the information about the code start point. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Richard Henderson <rth@twiddle.net> Message-Id: <1458052224-9316-3-git-send-email-alex.bennee@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22util: move declarations out of qemu-common.hVeronia Bahaa1-1/+1
Move declarations out of qemu-common.h for functions declared in utils/ files: e.g. include/qemu/path.h for utils/path.c. Move inline functions out of qemu-common.h and into new files (e.g. include/qemu/bcd.h) Signed-off-by: Veronia Bahaa <veroniabahaa@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-23tcg: Rename tcg-target.c to tcg-target.inc.cPeter Maydell1-3/+4
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>
2016-02-23tcg: Allocate indirect_base temporaries in a different orderRichard Henderson1-11/+32
Since we've not got liveness analysis for indirect bases, placing them at the end of the call-saved registers makes it more likely that it'll stay live. Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk> Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-02-23tcg: Implement indirect memory registersRichard Henderson1-29/+66
That is, global_mem registers whose base is another global_mem register, rather than a fixed register. Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk> Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-02-23tcg: Work around clang bug wrt enum ranges, part 2Richard Henderson1-1/+1
A previous patch patch changed the type of REG from int to enum TCGReg, which provokes the following bug in clang: https://llvm.org/bugs/show_bug.cgi?id=16154 Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-02-09tcg: Introduce temp_loadRichard Henderson1-64/+52
Unify all of the places that realize a temporary into a register. Reviewed-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-02-09tcg: Change temp_save argument to TCGTempRichard Henderson1-9/+7
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-02-09tcg: Change temp_sync argument to TCGTempRichard Henderson1-27/+28
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-02-09tcg: Change temp_dead argument to TCGTempRichard Henderson1-25/+23
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-02-09tcg: Change reg_to_temp to TCGTemp pointerRichard Henderson1-59/+54
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-02-09tcg: Remove tcg_get_arg_str_i32/64Richard Henderson1-10/+0
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-02-09tcg: More use of TCGReg where appropriateRichard Henderson1-11/+15
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-02-09tcg: Work around clang bug wrt enum rangesRichard Henderson1-6/+6
A subsequent patch patch will change the type of REG from int to enum TCGReg, which provokes the following bug in clang: https://llvm.org/bugs/show_bug.cgi?id=16154 Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-02-09tcg: Tidy temporary allocationRichard Henderson1-67/+56
In particular, make sure the memory is memset before use. Continues the increased use of TCGTemp pointers instead of integer indices where appropriate. Reviewed-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-02-09tcg: Change ts->mem_reg to ts->mem_baseRichard Henderson1-29/+36
Chain the temporaries together via pointers intstead of indices. The mem_reg value is now mem_base->reg. This will be important later. This does require that the frame pointer have a global temporary allocated for it. This is simple bar the existing reserved_regs check. Reviewed-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-02-09tcg: Change tcg_global_mem_new_* to take a TCGv_ptrRichard Henderson1-17/+4
Thus, use cpu_env as the parameter, not TCG_AREG0 directly. Update all uses in the translators. Reviewed-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-02-09tcg: Remove lingering references to gen_opc_bufRichard Henderson1-2/+1
Three in comments and one in code in the stub tcg_liveness_analysis. Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-02-09tcg: Respect highwater in tcg_out_tb_finalizeRichard Henderson1-7/+5
Undo the workaround at b17a6d3390f87620735f7efb03bb1c96682ff449. If there are lots of memory operations in a TB, the slow path code can exceed the highwater reservation. Add a check within the loop. Tested-by: Aurelien Jarno <aurelien@aurel32.net> Reviewed-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-02-03log: do not unnecessarily include qom/cpu.hPaolo Bonzini1-0/+1
Split the bits that require it to exec/log.h. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Denis V. Lunev <den@openvz.org> Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Message-id: 1452174932-28657-8-git-send-email-den@openvz.org Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-01-29tcg: Clean up includesPeter Maydell1-1/+1
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
2015-12-01tcg: Increase the highwater reservationRichard Henderson1-1/+5
If there are a lot of guest memory ops in the TB, the amount of code generated by tcg_out_tb_finalize could be well more than 1k. In the short term, increase the reservation larger than any TB seen in practice. Reported-by: Aurelien Jarno <aurelien@aurel32.net> Reviewed-by: Aurelien Jarno <aurelien@aurel32.net> Tested-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-11-23tcg: Fix highwater checkJohn Clarke1-1/+1
A simple typo in the variable to use when comparing vs the highwater mark. Reports are that qemu can in fact segfault occasionally due to this mistake. Signed-off-by: John Clarke <johnc@kirriwa.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-10-07tcg: Check for overflow via highwater markRichard Henderson1-3/+11
We currently pre-compute an worst case code size for any TB, which works out to be 122kB. Since the average TB size is near 1kB, this wastes quite a lot of storage. Instead, check for overflow in between generating code for each opcode. The overhead of the check isn't measurable and wastage is minimized. Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-10-07tcg: Emit prologue to the beginning of code_gen_bufferRichard Henderson1-7/+28
By putting the prologue at the end, we risk overwriting the prologue should our estimate of maximum TB size. Given the two different placements of the call to tcg_prologue_init, move the high water mark computation into tcg_prologue_init. Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-10-07tcg: Remove tcg_gen_code_search_pcRichard Henderson1-40/+19
It's no longer used, so tidy up everything reached by it. Reviewed-by: Aurelien Jarno <aurelien@aurel32.net> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-10-07tcg: Save insn data and use it in cpu_restore_state_from_tbRichard Henderson1-14/+26
We can now restore state without retranslation. Reviewed-by: Aurelien Jarno <aurelien@aurel32.net> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Richard Henderson <rth@twiddle.net>
generated by cgit v1.1 at 2024-12-26 04:24:41 +0000