Commit Graph

1326 Commits

Author SHA1 Message Date
John Clarke
644da9b39e tcg: Fix highwater check
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>
2015-11-23 13:16:05 +01:00
James Hogan
137d63902f tcg/mips: Support r6 SEL{NE, EQ}Z instead of MOVN/MOVZ
Extend MIPS movcond implementation to support the SELNEZ/SELEQZ
instructions introduced in MIPS r6 (where MOVN/MOVZ have been removed).

Whereas the "MOVN/MOVZ rd, rs, rt" instructions have the following
semantics:
 rd = [!]rt ? rs : rd

The "SELNEZ/SELEQZ rd, rs, rt" instructions are slightly different:
 rd = [!]rt ? rs : 0

First we ensure that if one of the movcond input values is zero that it
comes last (we can swap the input arguments if we invert the condition).
This is so that it can exactly match one of the SELNEZ/SELEQZ
instructions and avoid the need to emit the other one.

Otherwise we emit the opposite instruction first into a temporary
register, and OR that into the result:
 SELNEZ/SELEQZ  TMP1, v2, c1
 SELEQZ/SELNEZ  ret, v1, c1
 OR             ret, ret, TMP1

Which does the following:
 ret = cond ? v1 : v2

Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Message-Id: <1443788657-14537-7-git-send-email-james.hogan@imgtec.com>
2015-10-19 11:04:39 -10:00
James Hogan
bc6d0c22b0 tcg/mips: Support r6 multiply/divide encodings
MIPSr6 adds several new integer multiply, divide, and modulo
instructions, and removes several pre-r6 encodings, along with the HI/LO
registers which were the implicit operands of some of those
instructions. Update TCG to use the new instructions when built for r6.

The new instructions actually map much more directly to the TCG ops, as
they only provide a single 32-bit half of the result and in a normal
general purpose register instead of HI or LO.

The mulu2_i32 and muls2_i32 operations are no longer appropriate for r6,
so they are removed from the TCG opcode table. This is because they
would need to emit two separate host instructions anyway (for the high
and low half of the result), which TCG can arrange automatically for us
in the absense of mulu2_i32/muls2_i32 by splitting it into mul_i32 and
mul*h_i32 TCG ops.

Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Message-Id: <1443788657-14537-6-git-send-email-james.hogan@imgtec.com>
2015-10-19 11:04:39 -10:00
James Hogan
6e0d096989 tcg/mips: Support r6 JR encoding
MIPSr6 encodes JR as JALR with zero as the link register, and the pre-r6
JR encoding is removed. Update TCG to use the new encoding when built
for r6.

We still use the old encoding for pre-r6, so as not to confuse return
prediction stack hardware which may detect only particular encodings of
the return instruction.

Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Message-Id: <1443788657-14537-5-git-send-email-james.hogan@imgtec.com>
2015-10-19 11:04:38 -10:00
James Hogan
ce14bd4d46 tcg/mips: Add use_mips32r6_instructions definition
Add definition use_mips32r6_instructions to the MIPS TCG backend which
is constant 1 when built for MIPS release 6. This will be used to decide
between pre-R6 and R6 instruction encodings.

Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Message-Id: <1443788657-14537-4-git-send-email-james.hogan@imgtec.com>
2015-10-19 11:04:38 -10:00
James Hogan
c0e40dbdcc tcg-opc.h: Simplify insn_start def
We already have a TLADDR_ARGS definition, so rearrange the order
slightly and use it in the definition of insn_start, instead of
having an #ifdef.

Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Message-Id: <1443788657-14537-2-git-send-email-james.hogan@imgtec.com>
2015-10-19 11:04:38 -10:00
Richard Henderson
1e1df962e3 tcg/ppc: Prefer mask over andi.
Prefer the instruction that isn't required to modify cr0.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-10-19 11:04:38 -10:00
Richard Henderson
5bfd75a35c tcg/ppc: Revise goto_tb implementation
Restrict the size of code_gen_buffer to 2GB on ppc64, which
lets us assert that everything is reachable with addis+addi
from tb_ret_addr.  This lets us use a max of 4 insns for goto_tb
instead of 7.

Emit the indirect branch portion of goto_tb up front, which
means we only have to update two insns to update any link.
With a 64-bit store, we can update the link atomically, which
may be required in future.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-10-19 11:04:37 -10:00
Richard Henderson
70f897bdc4 tcg/ppc: Adjust exit_tb for change in prologue placement
Changing the prologue to the beginning of the code_gen_buffer
changes the direction of the "return" branch.  Need to change
the logic to match.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-10-19 11:04:37 -10:00
Richard Henderson
b125f9dc7b tcg: Check for overflow via highwater mark
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>
2015-10-07 20:36:53 +11:00
Richard Henderson
8163b74938 tcg: Emit prologue to the beginning of code_gen_buffer
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>
2015-10-07 20:36:53 +11:00
Richard Henderson
04fe640001 tcg: Remove tcg_gen_code_search_pc
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>
2015-10-07 20:36:53 +11:00
Richard Henderson
4e5e121515 tcg: Remove gen_intermediate_code_pc
It is no longer used, so tidy up everything reached by it.
This includes the gen_opc_* arrays, the search_pc parameter
and the inline gen_intermediate_code_internal functions.

Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-10-07 20:36:52 +11:00
Richard Henderson
fca8a500d5 tcg: Save insn data and use it in cpu_restore_state_from_tb
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>
2015-10-07 20:36:51 +11:00
Richard Henderson
bad729e272 tcg: Pass data argument to restore_state_to_opc
The gen_opc_* arrays are already redundant with the data stored in
the insn_start arguments.  Transition restore_state_to_opc to use
data from the latter.

Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-10-07 20:36:51 +11:00
Richard Henderson
190ce7fbc7 tcg: Add TCG_MAX_INSNS
Adjust all translators to respect it.

Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-10-07 20:36:50 +11:00
Richard Henderson
9aef40ed1f tcg: Allow extra data to be attached to insn_start
With an eye toward having this data replace the gen_opc_* arrays
that each target collects in order to enable restore_state_from_tb.

Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-10-07 20:36:46 +11:00
Richard Henderson
765b842ade tcg: Rename debug_insn_start to insn_start
With an eye toward making it mandatory.

Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-10-07 20:36:26 +11:00
Aurelien Jarno
81dfaf1a8f tcg/mips: pass oi to tcg_out_tlb_load
Instead of computing mem_index and s_bits in both tcg_out_qemu_ld and
tcg_out_qemu_st function and passing them to tcg_out_tlb_load, directly
pass oi to the tcg_out_tlb_load function and compute mem_index and
s_bits there.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2015-09-19 11:53:15 +02:00
Aurelien Jarno
d9f26847f1 tcg/mips: move tcg_out_addsub2
Somehow the tcg_out_addsub2 function ended-up in the middle of the
qemu_ld/st related functions. Move it with other arithmetics related
functions.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2015-09-19 11:53:14 +02:00
James Hogan
5eb4f645eb tcg/mips: Fix clobbering of qemu_ld inputs
The MIPS TCG backend implements qemu_ld with 64-bit targets using the v0
register (base) as a temporary to load the upper half of the QEMU TLB
comparator (see line 5 below), however this happens before the input
address is used (line 8 to mask off the low bits for the TLB
comparison, and line 12 to add the host-guest offset). If the input
address (addrl) also happens to have been placed in v0 (as in the second
column below), it gets clobbered before it is used.

     addrl in t2              addrl in v0

 1 srl     a0,t2,0x7        srl     a0,v0,0x7
 2 andi    a0,a0,0x1fe0     andi    a0,a0,0x1fe0
 3 addu    a0,a0,s0         addu    a0,a0,s0
 4 lw      at,9136(a0)      lw      at,9136(a0)      set TCG_TMP0 (at)
 5 lw      v0,9140(a0)      lw      v0,9140(a0)      set base (v0)
 6 li      t9,-4093         li      t9,-4093
 7 lw      a0,9160(a0)      lw      a0,9160(a0)      set addend (a0)
 8 and     t9,t9,t2         and     t9,t9,v0         use addrl
 9 bne     at,t9,0x836d8c8  bne     at,t9,0x836d838  use TCG_TMP0
10  nop                      nop
11 bne     v0,t8,0x836d8c8  bne     v0,a1,0x836d838  use base
12  addu   v0,a0,t2          addu   v0,a0,v0         use addrl, addend
13 lw      t0,0(v0)         lw      t0,0(v0)

Fix by using TCG_TMP0 (at) as the temporary instead of v0 (base),
pushing the load on line 5 forward into the delay slot of the low
comparison (line 10). The early load of the addend on line 7 also needs
pushing even further for 64-bit targets, or it will clobber a0 before
we're done with it. The output for 32-bit targets is unaffected.

 srl     a0,v0,0x7
 andi    a0,a0,0x1fe0
 addu    a0,a0,s0
 lw      at,9136(a0)
-lw      v0,9140(a0)      load high comparator
 li      t9,-4093
-lw      a0,9160(a0)      load addend
 and     t9,t9,v0
 bne     at,t9,0x836d838
- nop
+ lw     at,9140(a0)      load high comparator
+lw      a0,9160(a0)      load addend
-bne     v0,a1,0x836d838
+bne     at,a1,0x836d838
  addu   v0,a0,v0
 lw      t0,0(v0)

Cc: qemu-stable@nongnu.org
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2015-09-19 11:53:14 +02:00
Peter Crosthwaite
162e992270 tcg: Move tci_tb_ptr to -common
This requires global visibility to common code. Move to tcg-common.

Cc: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Peter Crosthwaite <crosthwaite.peter@gmail.com>
Message-Id: <cb0340eba225ab4945aa6cf7c9013f33aa05bcf8.1441614289.git.crosthwaite.peter@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-09-16 17:33:33 +02:00
Peter Crosthwaite
7d8f787d9d tcg: split tcg_op_defs to -common
tcg_op_defs (and the _max) are both needed by the TCI disassembler. For
multi-arch, tcg.c will be multiple-compiled (arch-obj) with its symbols
hidden from common code. So split the definition off to new file,
tcg-common.c which will remain a regular obj-y for use by both the TCI
disas as well as the multiple tcg.c's.

Cc: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Peter Crosthwaite <crosthwaite.peter@gmail.com>
Message-Id: <4b607425886d85aee65878e4935dfad46b3e6085.1441614289.git.crosthwaite.peter@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-09-16 17:33:33 +02:00
Peter Maydell
a2aa09e181 * Support for jemalloc
* qemu_mutex_lock_iothread "No such process" fix
 * cutils: qemu_strto* wrappers
 * iohandler.c simplification
 * Many other fixes and misc patches.
 
 And some MTTCG work (with Emilio's fixes squashed):
 * Signal-free TCG kick
 * Removing spinlock in favor of QemuMutex
 * User-mode emulation multi-threading fixes/docs
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Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into staging

* Support for jemalloc
* qemu_mutex_lock_iothread "No such process" fix
* cutils: qemu_strto* wrappers
* iohandler.c simplification
* Many other fixes and misc patches.

And some MTTCG work (with Emilio's fixes squashed):
* Signal-free TCG kick
* Removing spinlock in favor of QemuMutex
* User-mode emulation multi-threading fixes/docs

# gpg: Signature made Thu 10 Sep 2015 09:03:07 BST using RSA key ID 78C7AE83
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>"
# gpg:                 aka "Paolo Bonzini <pbonzini@redhat.com>"

* remotes/bonzini/tags/for-upstream: (44 commits)
  cutils: work around platform differences in strto{l,ul,ll,ull}
  cpu-exec: fix lock hierarchy for user-mode emulation
  exec: make mmap_lock/mmap_unlock globally available
  tcg: comment on which functions have to be called with mmap_lock held
  tcg: add memory barriers in page_find_alloc accesses
  remove unused spinlock.
  replace spinlock by QemuMutex.
  cpus: remove tcg_halt_cond and tcg_cpu_thread globals
  cpus: protect work list with work_mutex
  scripts/dump-guest-memory.py: fix after RAMBlock change
  configure: Add support for jemalloc
  add macro file for coccinelle
  configure: factor out adding disas configure
  vhost-scsi: fix wrong vhost-scsi firmware path
  checkpatch: remove tests that are not relevant outside the kernel
  checkpatch: adapt some tests to QEMU
  CODING_STYLE: update mixed declaration rules
  qmp: Add example usage of strto*l() qemu wrapper
  cutils: Add qemu_strtoull() wrapper
  cutils: Add qemu_strtoll() wrapper
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-09-14 16:13:16 +01:00
Pavel Dovgalyuk
282dffc8a4 softmmu: add helper function to pass through retaddr
This patch introduces several helpers to pass return address
which points to the TB. Correct return address allows correct
restoring of the guest PC and icount. These functions should be used when
helpers embedded into TB invoke memory operations.

Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Pavel Dovgalyuk <pavel.dovgaluk@ispras.ru>
Message-Id: <20150710095650.13280.32255.stgit@PASHA-ISP>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-09-11 08:15:32 -07:00
Veres Lajos
67cc32ebfd typofixes - v4
Signed-off-by: Veres Lajos <vlajos@gmail.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-09-11 10:45:43 +03:00
KONRAD Frederic
677ef6230b replace spinlock by QemuMutex.
spinlock is only used in two cases:
  * cpu-exec.c: to protect TranslationBlock
  * mem_helper.c: for lock helper in target-i386 (which seems broken).

It's a pthread_mutex_t in user-mode, so we can use QemuMutex directly,
with an #ifdef.  The #ifdef will be removed when multithreaded TCG
will need the mutex as well.

Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com>
Message-Id: <1439220437-23957-5-git-send-email-fred.konrad@greensocs.com>
Signed-off-by: Emilio G. Cota <cota@braap.org>
[Merge Emilio G. Cota's patch to remove volatile. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-09-09 15:34:55 +02:00
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
Richard Henderson
352bcb0a2b tcg/aarch64: Fix tcg_out_qemu_{ld, st} for guest_base == 0
In ffc6372851, we swapped the guest
base to the address base register from the address index register.
Except that 31 in the base slot is SP not XZR, so we need to be
more intelligent about which reg gets placed in which slot.

Cc: qemu-stable@nongnu.org (v2.4.0)
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reported-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-09-02 14:23:14 -07:00
Laurent Vivier
090d0bfd94 s390: fix softmmu compilation
guest_base must be used only in linux-user mode.

Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Message-id: 1440757421-9674-1-git-send-email-laurent@vivier.eu
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-08-28 16:05:24 +01:00
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
Laurent Vivier
4cbea59869 linux-user: remove --enable-guest-base/--disable-guest-base
All tcg host architectures now support the guest base and as
there is no real performance lost, it can be always enabled.

Anyway, guest base use can be disabled lively by setting guest
base to 0.

CONFIG_USE_GUEST_BASE is defined as (USE_GUEST_BASE && USER_ONLY),
it should have to be replaced by CONFIG_USER_ONLY in non CONFIG_USER_ONLY
parts, but as some other parts are using !CONFIG_SOFTMMU I have chosen to
use !CONFIG_SOFTMMU instead.

Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <1440373328-9788-2-git-send-email-laurent@vivier.eu>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-08-24 11:14:17 -07:00
Richard Henderson
9ee14902bf tcg/aarch64: Use softmmu fast path for unaligned accesses
Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-08-24 11:10:54 -07:00
Richard Henderson
a5e39810b9 tcg/s390: Use softmmu fast path for unaligned accesses
Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-08-24 11:10:54 -07:00
Benjamin Herrenschmidt
68d45bb61c tcg/ppc: Improve unaligned load/store handling on 64-bit backend
Currently, we get to the slow path for any unaligned access in the
backend, because we effectively preserve the bottom address bits
below the alignment requirement when comparing with the TLB entry,
so any non-0 bit there will cause the compare to fail.

For the same number of instructions, we can instead add the access
size - 1 to the address and stick to clearing all the bottom bits.

That means that normal unaligned accesses will not fallback (the HW
will handle them fine). Only when crossing a page boundary well we
end up having a mismatch because we'll end up pointing to the next
page which cannot possibly be in that same TLB entry.

Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Message-Id: <1437455978.5809.2.camel@kernel.crashing.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-08-24 11:10:54 -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
ecc7b3aa71 tcg: Remove tcg_gen_trunc_i64_i32
Replacing it with tcg_gen_extrl_i64_i32.

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
870ad1547a tcg: update README about size changing ops
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
8bcb5c8f34 tcg/optimize: add optimizations for ext_i32_i64 and extu_i32_i64 ops
They behave the same as ext32s_i64 and ext32u_i64 from the constant
folding and zero propagation point of view, except that they can't
be replaced by a mov, so we don't compute the affected value.

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
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
6acd2558fd tcg: don't abuse TCG type in tcg_gen_trunc_shr_i64_i32
The tcg_gen_trunc_shr_i64_i32 function takes a 64-bit argument and
returns a 32-bit value. Directly call tcg_gen_op3 with the correct
types instead of calling tcg_gen_op3i_i32 and abusing the TCG types.

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
Aurelien Jarno
299f801304 tcg/optimize: allow constant to have copies
Now that copies and constants are tracked separately, we can allow
constant to have copies, deferring the choice to use a register or a
constant to the register allocation pass. This prevent this kind of
regular constant reloading:

-OUT: [size=338]
+OUT: [size=298]
   mov    -0x4(%r14),%ebp
   test   %ebp,%ebp
   jne    0x7ffbe9cb0ed6
   mov    $0x40002219f8,%rbp
   mov    %rbp,(%r14)
-  mov    $0x40002219f8,%rbp
   mov    $0x4000221a20,%rbx
   mov    %rbp,(%rbx)
   mov    $0x4000000000,%rbp
   mov    %rbp,(%r14)
-  mov    $0x4000000000,%rbp
   mov    $0x4000221d38,%rbx
   mov    %rbp,(%rbx)
   mov    $0x40002221a8,%rbp
   mov    %rbp,(%r14)
-  mov    $0x40002221a8,%rbp
   mov    $0x4000221d40,%rbx
   mov    %rbp,(%rbx)
   mov    $0x4000019170,%rbp
   mov    %rbp,(%r14)
-  mov    $0x4000019170,%rbp
   mov    $0x4000221d48,%rbx
   mov    %rbp,(%rbx)
   mov    $0x40000049ee,%rbp
   mov    %rbp,0x80(%r14)
   mov    %r14,%rdi
   callq  0x7ffbe99924d0
   mov    $0x4000001680,%rbp
   mov    %rbp,0x30(%r14)
   mov    0x10(%r14),%rbp
   mov    $0x4000001680,%rbp
   mov    %rbp,0x30(%r14)
   mov    0x10(%r14),%rbp
   shl    $0x20,%rbp
   mov    (%r14),%rbx
   mov    %ebx,%ebx
   mov    %rbx,(%r14)
   or     %rbx,%rbp
   mov    %rbp,0x10(%r14)
   mov    %rbp,0x90(%r14)
   mov    0x60(%r14),%rbx
   mov    %rbx,0x38(%r14)
   mov    0x28(%r14),%rbx
   mov    $0x4000220e60,%r12
   mov    %rbx,(%r12)
   mov    $0x40002219c8,%rbx
   mov    %rbp,(%rbx)
   mov    0x20(%r14),%rbp
   sub    $0x8,%rbp
   mov    $0x4000004a16,%rbx
   mov    %rbx,0x0(%rbp)
   mov    %rbp,0x20(%r14)
   mov    $0x19,%ebp
   mov    %ebp,0xa8(%r14)
   mov    $0x4000015110,%rbp
   mov    %rbp,0x80(%r14)
   xor    %eax,%eax
   jmpq   0x7ffbebcae426
   lea    -0x5f6d72a(%rip),%rax        # 0x7ffbe3d437b3
   jmpq   0x7ffbebcae426

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
b41059dd9d tcg/optimize: track const/copy status separately
Instead of using an enum which could be either a copy or a const, track
them separately. This will be used in the next patch.

Constants are tracked through a bool. Copies are tracked by initializing
temp's next_copy and prev_copy to itself, allowing to simplify the code
a bit.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-08-24 11:10:53 -07:00
Aurelien Jarno
d9c769c609 tcg/optimize: add temp_is_const and temp_is_copy functions
Add two accessor functions temp_is_const and temp_is_copy, to make the
code more readable and make code change easier.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-08-24 11:10:53 -07:00
Aurelien Jarno
1208d7dd5f tcg/optimize: optimize temps tracking
The tcg_temp_info structure uses 24 bytes per temp. Now that we emulate
vector registers on most guests, it's not uncommon to have more than 100
used temps. This means we have initialize more than 2kB at least twice
per TB, often more when there is a few goto_tb.

Instead used a TCGTempSet bit array to track which temps are in used in
the current basic block. This means there are only around 16 bytes to
initialize.

This improves the boot time of a MIPS guest on an x86-64 host by around
7% and moves out tcg_optimize from the the top of the profiler list.

[rth: Handle TCG_CALL_DUMMY_ARG]

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-08-24 11:10:30 -07:00
Aurelien Jarno
29f3ff8d6c tcg/optimize: fix constant signedness
By convention, on a 64-bit host TCG internally stores 32-bit constants
as sign-extended. This is not the case in the optimizer when a 32-bit
constant is folded.

This doesn't seem to have more consequences than suboptimal code
generation. For instance the x86 backend assumes sign-extended constants,
and in some rare cases uses a 32-bit unsigned immediate 0xffffffff
instead of a 8-bit signed immediate 0xff for the constant -1. This is
with a ppc guest:

before
------

 ---- 0x9f29cc
 movi_i32 tmp1,$0xffffffff
 movi_i32 tmp2,$0x0
 add2_i32 tmp0,CA,CA,tmp2,r6,tmp2
 add2_i32 tmp0,CA,tmp0,CA,tmp1,tmp2
 mov_i32 r10,tmp0

0x7fd8c7dfe90c:  xor    %ebp,%ebp
0x7fd8c7dfe90e:  mov    %ebp,%r11d
0x7fd8c7dfe911:  mov    0x18(%r14),%r9d
0x7fd8c7dfe915:  add    %r9d,%r10d
0x7fd8c7dfe918:  adc    %ebp,%r11d
0x7fd8c7dfe91b:  add    $0xffffffff,%r10d
0x7fd8c7dfe922:  adc    %ebp,%r11d
0x7fd8c7dfe925:  mov    %r11d,0x134(%r14)
0x7fd8c7dfe92c:  mov    %r10d,0x28(%r14)

after
-----

 ---- 0x9f29cc
 movi_i32 tmp1,$0xffffffffffffffff
 movi_i32 tmp2,$0x0
 add2_i32 tmp0,CA,CA,tmp2,r6,tmp2
 add2_i32 tmp0,CA,tmp0,CA,tmp1,tmp2
 mov_i32 r10,tmp0

0x7f37010d490c:  xor    %ebp,%ebp
0x7f37010d490e:  mov    %ebp,%r11d
0x7f37010d4911:  mov    0x18(%r14),%r9d
0x7f37010d4915:  add    %r9d,%r10d
0x7f37010d4918:  adc    %ebp,%r11d
0x7f37010d491b:  add    $0xffffffffffffffff,%r10d
0x7f37010d491f:  adc    %ebp,%r11d
0x7f37010d4922:  mov    %r11d,0x134(%r14)
0x7f37010d4929:  mov    %r10d,0x28(%r14)

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Message-Id: <1436544211-2769-2-git-send-email-aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-08-24 11:10:08 -07:00
Aurelien Jarno
c99d69694a tcg/mips: fix add2
The add2 code in the tcg_out_addsub2 function doesn't take into account
the case where rl == al == bl. In that case we can't compute the carry
after the addition. As it corresponds to a multiplication by 2, the
carry bit is the bit 31.

While this is a corner case, this prevents x86-64 guests to boot on a
MIPS host.

Cc: qemu-stable@nongnu.org
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2015-08-01 09:39:50 +02:00
Aurelien Jarno
3c8691f568 tcg/s390x: Mask TCGMemOp appropriately for indexing
Commit 2b7ec66f fixed TCGMemOp masking following the MO_AMASK addition,
but two cases were forgotten in the TCG S390 backend.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2015-08-01 09:39:37 +02:00