qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
* [PATCH v3 00/19] tcg: Better handling of constants
@ 2020-05-08 15:17 Richard Henderson
  2020-05-08 15:17 ` [PATCH v3 01/19] tcg: Consolidate 3 bits into enum TCGTempKind Richard Henderson
                   ` (19 more replies)
  0 siblings, 20 replies; 23+ messages in thread
From: Richard Henderson @ 2020-05-08 15:17 UTC (permalink / raw)
  To: qemu-devel; +Cc: alex.bennee

V3 fixes the target/sparc regression during register allocation.

V1 blurb:

This promotes constants to full-fledged temporaries, which are then
hashed so we have only a single copy across the TB.  If an opcode
requires forcing one into a register, then we will only do this
once -- at least until the register is killed, e.g. by a function call.

While this is probably an modest improvement for integer code, it is
significant for SVE vector code.  In particular, where a generator function
loads a constant for the operation, and then the generator function is
called N times for the N x 128-bit vector.  Previously we'd be loading
up the same constant N times and now we do so only once.

The existing tcg_const_{type}() functions are unchanged, allocating
a new temporary and initializing it.  The constant propagation pass
of the optimizer will generally remove the temporary when it turns
out not to be modified further.

This adds new tcg_constant_{type}() functions which produce a read-only
temporary containing the constant which need not be freed.  I have
updated the generic expanders to take advantage of this, but have not
touched the target front ends.

This also, in the end, allows the complete removal of the tcg opcodes
that create a constant: INDEX_op_movi_{i32,i64} and INDEX_op_dupi_vec.
Loading of constants into hard registers is completely controlled by
the register allocator.


r~


Richard Henderson (19):
  tcg: Consolidate 3 bits into enum TCGTempKind
  tcg: Add temp_readonly
  tcg: Introduce TYPE_CONST temporaries
  tcg: Use tcg_constant_i32 with icount expander
  tcg: Use tcg_constant_{i32,i64} with tcg int expanders
  tcg: Use tcg_constant_{i32,vec} with tcg vec expanders
  tcg: Use tcg_constant_{i32,i64,vec} with tcg gvec expanders
  tcg: Use tcg_constant_{i32,i64} with tcg plugins
  tcg: Rename struct tcg_temp_info to TempOptInfo
  tcg/optimize: Improve find_better_copy
  tcg/optimize: Adjust TempOptInfo allocation
  tcg/optimize: Use tcg_constant_internal with constant folding
  tcg/tci: Add special tci_movi_{i32,i64} opcodes
  tcg: Remove movi and dupi opcodes
  tcg: Use tcg_out_dupi_vec from temp_load
  tcg: Increase tcg_out_dupi_vec immediate to int64_t
  tcg: Add tcg_reg_alloc_dup2
  tcg/i386: Use tcg_constant_vec with tcg vec expanders
  tcg: Remove tcg_gen_dup{8,16,32,64}i_vec

 include/exec/gen-icount.h    |  25 +--
 include/tcg/tcg-op.h         |  17 +-
 include/tcg/tcg-opc.h        |  11 +-
 include/tcg/tcg.h            |  50 ++++-
 accel/tcg/plugin-gen.c       |  49 ++---
 tcg/aarch64/tcg-target.inc.c |  12 +-
 tcg/arm/tcg-target.inc.c     |   1 -
 tcg/i386/tcg-target.inc.c    | 110 ++++++----
 tcg/mips/tcg-target.inc.c    |   2 -
 tcg/optimize.c               | 204 +++++++++---------
 tcg/ppc/tcg-target.inc.c     |  24 +--
 tcg/riscv/tcg-target.inc.c   |   2 -
 tcg/s390/tcg-target.inc.c    |   2 -
 tcg/sparc/tcg-target.inc.c   |   2 -
 tcg/tcg-op-gvec.c            | 125 +++++------
 tcg/tcg-op-vec.c             |  83 ++++----
 tcg/tcg-op.c                 | 216 +++++++++----------
 tcg/tcg.c                    | 397 ++++++++++++++++++++++++++---------
 tcg/tci.c                    |   4 +-
 tcg/tci/tcg-target.inc.c     |   6 +-
 20 files changed, 751 insertions(+), 591 deletions(-)

-- 
2.20.1



^ permalink raw reply	[flat|nested] 23+ messages in thread

end of thread, other threads:[~2020-05-08 18:58 UTC | newest]

Thread overview: 23+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2020-05-08 15:17 [PATCH v3 00/19] tcg: Better handling of constants Richard Henderson
2020-05-08 15:17 ` [PATCH v3 01/19] tcg: Consolidate 3 bits into enum TCGTempKind Richard Henderson
2020-05-08 18:57   ` Philippe Mathieu-Daudé
2020-05-08 15:17 ` [PATCH v3 02/19] tcg: Add temp_readonly Richard Henderson
2020-05-08 15:17 ` [PATCH v3 03/19] tcg: Introduce TYPE_CONST temporaries Richard Henderson
2020-05-08 15:17 ` [PATCH v3 04/19] tcg: Use tcg_constant_i32 with icount expander Richard Henderson
2020-05-08 15:17 ` [PATCH v3 05/19] tcg: Use tcg_constant_{i32, i64} with tcg int expanders Richard Henderson
2020-05-08 15:17 ` [PATCH v3 06/19] tcg: Use tcg_constant_{i32, vec} with tcg vec expanders Richard Henderson
2020-05-08 15:17 ` [PATCH v3 07/19] tcg: Use tcg_constant_{i32, i64, vec} with tcg gvec expanders Richard Henderson
2020-05-08 15:17 ` [PATCH v3 08/19] tcg: Use tcg_constant_{i32,i64} with tcg plugins Richard Henderson
2020-05-08 15:17 ` [PATCH v3 09/19] tcg: Rename struct tcg_temp_info to TempOptInfo Richard Henderson
2020-05-08 15:17 ` [PATCH v3 10/19] tcg/optimize: Improve find_better_copy Richard Henderson
2020-05-08 15:17 ` [PATCH v3 11/19] tcg/optimize: Adjust TempOptInfo allocation Richard Henderson
2020-05-08 15:17 ` [PATCH v3 12/19] tcg/optimize: Use tcg_constant_internal with constant folding Richard Henderson
2020-05-08 15:17 ` [PATCH v3 13/19] tcg/tci: Add special tci_movi_{i32,i64} opcodes Richard Henderson
2020-05-08 15:17 ` [PATCH v3 14/19] tcg: Remove movi and dupi opcodes Richard Henderson
2020-05-08 15:17 ` [PATCH v3 15/19] tcg: Use tcg_out_dupi_vec from temp_load Richard Henderson
2020-05-08 15:17 ` [PATCH v3 16/19] tcg: Increase tcg_out_dupi_vec immediate to int64_t Richard Henderson
2020-05-08 15:17 ` [PATCH v3 17/19] tcg: Add tcg_reg_alloc_dup2 Richard Henderson
2020-05-08 15:17 ` [PATCH v3 18/19] tcg/i386: Use tcg_constant_vec with tcg vec expanders Richard Henderson
2020-05-08 15:17 ` [PATCH v3 19/19] tcg: Remove tcg_gen_dup{8,16,32,64}i_vec Richard Henderson
2020-05-08 16:15 ` [PATCH v3 00/19] tcg: Better handling of constants Alex Bennée
2020-05-08 17:02   ` Richard Henderson

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).