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  1. 28 10月, 2012 9 次提交
    • A
      tcg: rewrite tcg_reg_alloc_mov() · c29c1d7e
      由 Aurelien Jarno 提交于 
      Now that the liveness analysis provides more information, rewrite
tcg_reg_alloc_mov(). This changes the behaviour about propagating
constants and memory accesses. We now take the assumption that once
a value is loaded into a register (from memory or from a constant),
it's better to keep it there than to reload it later. This assumption
is now always almost correct given that we are now sure the
corresponding temp is going to be used later (otherwise it would have
been synchronized and marked as dead already). The assumption is wrong
if one of the op after clobbers some registers including the one
of the holding the temp (this can be avoided by allocating clobbered
registers last, which is what most TCG target do), or in case of lack
of available register.
Reviewed-by: NRichard Henderson <rth@twiddle.net>
Signed-off-by: NAurelien Jarno <aurelien@aurel32.net>
      c29c1d7e
    • A
      tcg: improve tcg_reg_alloc_movi() · 4c4e1ab2
      由 Aurelien Jarno 提交于 
      Now that the liveness analysis might mark some output temps as dead, call
temp_dead() if needed.
Reviewed-by: NRichard Henderson <rth@twiddle.net>
Signed-off-by: NAurelien Jarno <aurelien@aurel32.net>
      4c4e1ab2
    • A
      tcg: rework liveness analysis · 9c43b68d
      由 Aurelien Jarno 提交于 
      Rework the liveness analysis by tracking temps that need to go back to
memory in addition to dead temps tracking. This allows to mark output
arguments as "need sync", and to synchronize them back to memory as soon
as they are not written anymore. This way even arguments mapping to
globals can be marked as "dead", avoiding moves to a new register when
input and outputs are aliased.

In addition it means that registers are freed as soon as temps are not
used anymore, instead of waiting for a basic block end or an op with side
effects. This reduces register spilling especially on CPUs with few
registers, and spread the mov over all the TB, increasing the
performances on in-order CPUs.
Reviewed-by: NRichard Henderson <rth@twiddle.net>
Signed-off-by: NAurelien Jarno <aurelien@aurel32.net>
      9c43b68d
    • A
      tcg: sync output arguments on liveness request · ec7a869d
      由 Aurelien Jarno 提交于 
      Synchronize an output argument when requested by the liveness analysis.
This is needed so that the temp can be declared dead later.

For that, add a new op_sync_args table in which each bit tells if the
corresponding output argument needs to be synchronized with the memory.
Pass it to the tcg_reg_alloc_* functions, and honor this bit. We need to
synchronize the argument before marking it as dead, and we have to make
sure all the infos about the temp are correctly filled.

At the same time change some types from unsigned int to uint16_t when
passing op_dead_args.
Reviewed-by: NRichard Henderson <rth@twiddle.net>
Signed-off-by: NAurelien Jarno <aurelien@aurel32.net>
      ec7a869d
    • A
      tcg: add temp_sync() · 1ad80729
      由 Aurelien Jarno 提交于 
      Add a new function temp_sync() to synchronize the canonical location
of a temp with the value in the corresponding register, but without
freeing the associated register. Rewrite temp_save() to call
temp_sync() followed by temp_dead().
Reviewed-by: NRichard Henderson <rth@twiddle.net>
Signed-off-by: NAurelien Jarno <aurelien@aurel32.net>
      1ad80729
    • A
      tcg: add tcg_reg_sync() · 7f6ceedf
      由 Aurelien Jarno 提交于 
      Add a new function tcg_reg_sync() to synchronize the canonical location
of a temp with the value in the associated register, but without freeing
it. Rewrite tcg_reg_free() to first call tcg_reg_sync() and then to free
the register.
Reviewed-by: NRichard Henderson <rth@twiddle.net>
Signed-off-by: NAurelien Jarno <aurelien@aurel32.net>
      7f6ceedf
    • A
      tcg: add temp_dead() · 639368dd
      由 Aurelien Jarno 提交于 
      A lot of code is duplicated to mark a temporary as dead. Replace it
by temp_dead(), which in addition marks the temp as saved in memory
for globals and local temps, instead of doing this a posteriori in
temp_save().
Reviewed-by: NRichard Henderson <rth@twiddle.net>
Signed-off-by: NAurelien Jarno <aurelien@aurel32.net>
      639368dd
    • A
      tcg/i386: remove ld/st third argument register constraint · 17b91491
      由 Aurelien Jarno 提交于 
      On x86_64, remove the constraint on the third argument register which
is not needed:
 - For loads the helper arguments are env, addr, mem_idx. The addr
   value should not be in the two first argument registers as they are
   used in tcg_out_tlb_load().
 - For stores the helper arguments are env, addr, data, mem_idx.
   The addr and data values should not be in the two first argument
   registers as they are used in tcg_out_tlb_load(). The data value
   should also not be in the two first argument registers, but could
   be in the third argument register in which case it would be already
   loaded at the right location.
Reviewed-by: NRichard Henderson <rth@twiddle.net>
Signed-off-by: NAurelien Jarno <aurelien@aurel32.net>
      17b91491
    • A
      tcg/i386: remove suboptimal register shifting · 166792f7
      由 Aurelien Jarno 提交于 
      Now that CONFIG_TCG_PASS_AREG0 has been removed, it's easier to get
an optimal code for the load/store functions.

First swap the two registers used in tcg_out_tlb_load() so that the
address end-up in the second register instead of the first one. Adjust
tcg_out_qemu_ld() and tcg_out_qemu_st() to respectively call
tcg_out_qemu_ld_direct() and tcg_out_qemu_st_direct() with the correct
registers. Then replace the register shifting by direct load of the
arguments.
Reviewed-by: NRichard Henderson <rth@twiddle.net>
Signed-off-by: NAurelien Jarno <aurelien@aurel32.net>
      166792f7
  3. 27 10月, 2012 8 次提交
  5. 25 10月, 2012 1 次提交
  7. 24 10月, 2012 13 次提交
  9. 23 10月, 2012 9 次提交