Commit Graph

70 Commits

Author SHA1 Message Date
Richard Henderson
e8939e801c target/hexagon: Use translator_ldl in pkt_crosses_page
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2024-05-15 08:55:19 +02:00
Richard Henderson
962a145cdc accel/tcg: Provide default implementation of disas_log
Almost all of the disas_log implementations are identical.
Unify them within translator_loop.

Drop extra Priv/Virt logging from target/riscv.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2024-05-15 08:55:18 +02:00
Richard Henderson
8018947230 accel/tcg: Use vaddr in translator_ld*
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2024-05-15 08:54:31 +02:00
Taylor Simpson
763d2ce7c4 Hexagon (target/hexagon) Enable more short-circuit packets (HVX)
Look for read-after-write instead of overlap of reads and writes

HVX instructions with helpers have pass-by-reference semantics, so
we check for overlaps of reads and writes within the same instruction.

Signed-off-by: Taylor Simpson <ltaylorsimpson@gmail.com>
Reviewed-by: Brian Cain <bcain@quicinc.com>
Message-Id: <20240201103340.119081-4-ltaylorsimpson@gmail.com>
Signed-off-by: Brian Cain <bcain@quicinc.com>
2024-05-05 16:22:07 -07:00
Taylor Simpson
bd983f68ac Hexagon (target/hexagon) Enable more short-circuit packets (scalar core)
Look for read-after-write instead of overlap of reads and writes

Here is an example with overalp but no read-after-write:
0x000200fc:  0x38103876	{	R0 = add(R0,R1); R6 = add(R6,R7) }

BEFORE:
 ---- 00000000000200fc
 mov_i32 loc2,$0x0
 mov_i32 loc2,r0
 add_i32 loc3,loc2,r1
 mov_i32 loc2,loc3
 mov_i32 loc4,$0x0
 mov_i32 loc4,r6
 add_i32 loc5,loc4,r7
 mov_i32 loc4,loc5
 mov_i32 r0,loc2
 mov_i32 r6,loc4

AFTER:
 ---- 00000000000200fc
 add_i32 loc2,r0,r1
 mov_i32 r0,loc2
 add_i32 loc3,r6,r7
 mov_i32 r6,loc3

We can also short-circuit packets with .new values by reading from the
real destination instead of the temporary.
0x00020100:  0x78005ff3	{	R19 = #0xff
0x00020104:  0x2002e204		if (cmp.eq(N19.new,R2)) jump:t PC+8 }

BEFORE:
 ---- 0000000000020100
 mov_i32 pc,$0x20108
 mov_i32 loc8,$0x0
 mov_i32 loc8,$0xff
 setcond_i32 loc10,loc8,r2,eq
 mov_i32 loc6,loc10
 mov_i32 r19,loc8
 add_i32 pkt_cnt,pkt_cnt,$0x2
 add_i32 insn_cnt,insn_cnt,$0x4
 brcond_i32 loc6,$0x0,eq,$L1
 goto_tb $0x0
 mov_i32 pc,$0x20108
 exit_tb $0x7fbb54000040
 set_label $L1
 goto_tb $0x1
 exit_tb $0x7fbb54000041
 set_label $L0
 exit_tb $0x7fbb54000043

AFTER:
 ---- 0000000000020100
 mov_i32 pc,$0x20108
 mov_i32 r19,$0xff
 setcond_i32 loc7,r19,r2,eq
 mov_i32 loc4,loc7
 add_i32 pkt_cnt,pkt_cnt,$0x2
 add_i32 insn_cnt,insn_cnt,$0x4
 brcond_i32 loc4,$0x0,eq,$L1
 goto_tb $0x0
 mov_i32 pc,$0x20108
 exit_tb $0x7f9764000040
 set_label $L1
 goto_tb $0x1
 exit_tb $0x7f9764000041
 set_label $L0
 exit_tb $0x7f9764000043

Signed-off-by: Taylor Simpson <ltaylorsimpson@gmail.com>
Reviewed-by: Brian Cain <bcain@quicinc.com>
Message-Id: <20240201103340.119081-3-ltaylorsimpson@gmail.com>
Signed-off-by: Brian Cain <bcain@quicinc.com>
2024-05-05 16:22:07 -07:00
Philippe Mathieu-Daudé
4597463b38 accel: Include missing 'exec/cpu_ldst.h' header
Theses files call cpu_ldl_code() which is declared
in "exec/cpu_ldst.h".

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20231211212003.21686-5-philmd@linaro.org>
2024-04-26 15:31:37 +02:00
Anton Johansson
85c19af63e include/exec: Use vaddr in DisasContextBase for virtual addresses
Updates target/ QEMU_LOG macros to use VADDR_PRIx for printing updated
DisasContextBase fields.

Signed-off-by: Anton Johansson <anjo@rev.ng>
Message-Id: <20240119144024.14289-10-anjo@rev.ng>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2024-01-29 07:06:03 +10:00
Anton Johansson
32f0c394bb target: Use vaddr in gen_intermediate_code
Makes gen_intermediate_code() signature target agnostic so the function
can be called from accel/tcg/translate-all.c without target specifics.

Signed-off-by: Anton Johansson <anjo@rev.ng>
Message-Id: <20240119144024.14289-9-anjo@rev.ng>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2024-01-29 07:06:03 +10:00
Taylor Simpson
1547a2d339 Hexagon (target/hexagon) Use QEMU decodetree (32-bit instructions)
The Decodetree Specification can be found here
https://www.qemu.org/docs/master/devel/decodetree.html

Covers all 32-bit instructions, including HVX

We generate separate decoders for each instruction class.  The reason
will be more apparent in the next patch in this series.

We add 2 new scripts
    gen_decodetree.py        Generate the input to decodetree.py
    gen_trans_funcs.py       Generate the trans_* functions used by the
                             output of decodetree.py

Since the functions generated by decodetree.py take DisasContext * as an
argument, we add the argument to a couple of functions that didn't need
it previously.  We also set the insn field in DisasContext during decode
because it is used by the trans_* functions.

There is a g_assert_not_reached() in decode_insns() in decode.c to
verify we never try to use the old decoder on 32-bit instructions

Signed-off-by: Taylor Simpson <ltaylorsimpson@gmail.com>
Reviewed-by: Brian Cain <bcain@quicinc.com>
Message-Id: <20240115221443.365287-2-ltaylorsimpson@gmail.com>
Signed-off-by: Brian Cain <bcain@quicinc.com>
2024-01-21 22:02:33 -08:00
Brian Cain
20c34a9216 target/hexagon: fix some occurrences of -Wshadow=local
Of the changes in this commit, the changes in `HELPER(commit_hvx_stores)()`
are less obvious.  They are required because of some macro invocations like
SCATTER_OP_WRITE_TO_MEM().

e.g.:

    In file included from ../target/hexagon/op_helper.c:31:
    ../target/hexagon/mmvec/macros.h:205:18: error: declaration of ‘i’ shadows a previous local [-Werror=shadow=compatible-local]
      205 |         for (int i = 0; i < sizeof(MMVector); i += sizeof(TYPE)) { \
          |                  ^
    ../target/hexagon/op_helper.c:157:17: note: in expansion of macro ‘SCATTER_OP_WRITE_TO_MEM’
      157 |                 SCATTER_OP_WRITE_TO_MEM(uint16_t);
          |                 ^~~~~~~~~~~~~~~~~~~~~~~
    ../target/hexagon/op_helper.c:135:9: note: shadowed declaration is here
      135 |     int i;
          |         ^
    In file included from ../target/hexagon/op_helper.c:31:
    ../target/hexagon/mmvec/macros.h:204:19: error: declaration of ‘ra’ shadows a previous local [-Werror=shadow=compatible-local]
      204 |         uintptr_t ra = GETPC(); \
          |                   ^~
    ../target/hexagon/op_helper.c:160:17: note: in expansion of macro ‘SCATTER_OP_WRITE_TO_MEM’
      160 |                 SCATTER_OP_WRITE_TO_MEM(uint32_t);
          |                 ^~~~~~~~~~~~~~~~~~~~~~~
    ../target/hexagon/op_helper.c:134:15: note: shadowed declaration is here
      134 |     uintptr_t ra = GETPC();
          |               ^~

Reviewed-by: Matheus Tavares Bernardino <quic_mathbern@quicinc.com>
Signed-off-by: Brian Cain <bcain@quicinc.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20231008220945.983643-3-bcain@quicinc.com>
2023-10-18 16:56:17 -07:00
Richard Henderson
b77af26e97 accel/tcg: Replace CPUState.env_ptr with cpu_env()
Reviewed-by: Anton Johansson <anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-10-04 11:03:54 -07:00
Richard Henderson
ad75a51e84 tcg: Rename cpu_env to tcg_env
Allow the name 'cpu_env' to be used for something else.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-10-03 08:01:02 -07:00
Philippe Mathieu-Daudé
026ad97e07 target/translate: Remove unnecessary 'exec/cpu_ldst.h' header
All these files only access the translator_ld/st API declared
in "exec/translator.h". The CPU ld/st API from declared in
"exec/cpu_ldst.h" is not used, remove it.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230828221314.18435-5-philmd@linaro.org>
2023-08-31 19:47:43 +02:00
Richard Henderson
d654e92817 target/*: Add missing includes of exec/translation-block.h
This had been pulled in via exec/exec-all.h, via exec/translator.h,
but the include of exec-all.h will be removed.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-06-05 12:04:29 -07:00
Richard Henderson
c213ee2dfc tcg: Split helper-proto.h
Create helper-proto-common.h without the target specific portion.
Use that in tcg-op-common.h.  Include helper-proto.h in target/arm
and target/hexagon before helper-info.c.inc; all other targets are
already correct in this regard.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-06-05 12:04:29 -07:00
Richard Henderson
d53106c997 tcg: Pass TCGHelperInfo to tcg_gen_callN
In preparation for compiling tcg/ only once, eliminate
the all_helpers array.  Instantiate the info structs for
the generic helpers in accel/tcg/, and the structs for
the target-specific helpers in each translate.c.

Since we don't see all of the info structs at startup,
initialize at first use, using g_once_init_* to make
sure we don't race while doing so.

Reviewed-by: Anton Johansson <anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-06-05 12:04:29 -07:00
Richard Henderson
13e27d1fa4 target/hexagon: Include helper-gen.h where needed
This had been included via tcg-op-common.h via tcg-op.h,
but that is going away.  In idef-parser.y, shuffle some
tcg related includes into a more logical order.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-06-05 12:04:28 -07:00
Matheus Tavares Bernardino
2babbd9390 Hexagon: fix outdated hex_new_* comments
Some code comments refer to hex_new_value and hex_new_pred_value, which
have been transferred to DisasContext and, in the case of hex_new_value,
should now be accessed through get_result_gpr().

In order to fix this outdated comments and also avoid having to tweak
them whenever we make a variable name change in the future, let's
replace them with pseudocode.

Suggested-by: Taylor Simpson <tsimpson@quicinc.com>
Signed-off-by: Matheus Tavares Bernardino <quic_mathbern@quicinc.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <8e1689e28dd7b1318369b55127cf47b82ab75921.1684939078.git.quic_mathbern@quicinc.com>
2023-05-26 07:03:41 -07:00
Taylor Simpson
0fc56c4375 Hexagon (target/hexagon) Move items to DisasContext
The following items in the CPUHexagonState are only used for bookkeeping
within the translation of a packet.  With recent changes that eliminate
the need to free TCGv variables, these make more sense to be transient
and kept in DisasContext.

The following items are moved
    dczero_addr
    branch_taken
    this_PC

Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230427230012.3800327-22-tsimpson@quicinc.com>
2023-05-18 12:40:52 -07:00
Taylor Simpson
e5d0d78db4 Hexagon (target/hexagon) Move pkt_has_store_s1 to DisasContext
The pkt_has_store_s1 field is only used for bookkeeping helpers with
a load.  With recent changes that eliminate the need to free TCGv
variables, it makes more sense to make this transient.

These helpers already take the instruction slot as an argument.  We
combine the slot and pkt_has_store_s1 into a single argument called
slotval.

Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230427230012.3800327-21-tsimpson@quicinc.com>
2023-05-18 12:40:52 -07:00
Taylor Simpson
842b206f26 Hexagon (target/hexagon) Move pred_written to DisasContext
The pred_written variable in the CPUHexagonState is only used for
bookkeeping within the translation of a packet.  With recent changes
that eliminate the need to free TCGv variables, these make more sense
to be transient and kept in DisasContext.

Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230427230012.3800327-20-tsimpson@quicinc.com>
2023-05-18 12:40:52 -07:00
Taylor Simpson
e22edc7c1d Hexagon (target/hexagon) Move new_pred_value to DisasContext
The new_pred_value array in the CPUHexagonState is only used for
bookkeeping within the translation of a packet.  With recent changes
that eliminate the need to free TCGv variables, these make more sense
to be transient and kept in DisasContext.

Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230427230012.3800327-19-tsimpson@quicinc.com>
2023-05-18 12:40:52 -07:00
Taylor Simpson
4ff5676474 Hexagon (target/hexagon) Move new_value to DisasContext
The new_value array in the CPUHexagonState is only used for bookkeeping
within the translation of a packet.  With recent changes that eliminate
the need to free TCGv variables, these make more sense to be transient
and kept in DisasContext.

Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230427230012.3800327-18-tsimpson@quicinc.com>
2023-05-18 12:40:52 -07:00
Taylor Simpson
6aa4f1d15c Hexagon (target/hexagon) Make special new_value for USR
Precursor to moving new_value from the global state to DisasContext

USR will need to stay in the global state because some helpers will
set it's value

Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230427230012.3800327-17-tsimpson@quicinc.com>
2023-05-18 12:40:52 -07:00
Taylor Simpson
d05d5eebc7 Hexagon (target/hexagon) Short-circuit more HVX single instruction packets
The generated helpers for HVX use pass-by-reference, so they can't
short-circuit when the reads/writes overlap.  The instructions with
overrides are OK because they use tcg_gen_gvec_*.

We add a flag has_hvx_helper to DisasContext and extend gen_analyze_funcs
to set the flag when the instruction is an HVX instruction with a
generated helper.

We add an override for V6_vcombine so that it can be short-circuited
along with a test case in tests/tcg/hexagon/hvx_misc.c

Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230427230012.3800327-15-tsimpson@quicinc.com>
2023-05-18 12:40:52 -07:00
Taylor Simpson
b85529854e Hexagon (target/hexagon) Short-circuit packet HVX writes
In certain cases, we can avoid the overhead of writing to future_VRegs
and write directly to VRegs.  We consider HVX reads/writes when computing
ctx->need_commit.  Then, we can early-exit from gen_commit_hvx.

Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230427230012.3800327-14-tsimpson@quicinc.com>
2023-05-18 12:40:52 -07:00
Taylor Simpson
455e169d7c Hexagon (target/hexagon) Short-circuit packet predicate writes
In certain cases, we can avoid the overhead of writing to hex_new_pred_value
and write directly to hex_pred.  We consider predicate reads/writes when
computing ctx->need_commit.  The get_result_pred() function uses this
field to decide between hex_new_pred_value and hex_pred.  Then, we can
early-exit from gen_pred_writes.

Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230427230012.3800327-13-tsimpson@quicinc.com>
2023-05-18 12:40:52 -07:00
Taylor Simpson
d54c56156f Hexagon (target/hexagon) Short-circuit packet register writes
In certain cases, we can avoid the overhead of writing to hex_new_value
and write directly to hex_gpr.  We add need_commit field to DisasContext
indicating if the end-of-packet commit is needed.  If it is not needed,
get_result_gpr() and get_result_gpr_pair() can return hex_gpr.

We pass the ctx->need_commit to helpers when needed.

Finally, we can early-exit from gen_reg_writes during packet commit.

There are a few instructions whose semantics write to the result before
reading all the inputs.  Therefore, the idef-parser generated code is
incompatible with short-circuit.  We tell idef-parser to skip them.

For debugging purposes, we add a cpu property to turn off short-circuit.
When the short-circuit property is false, we skip the analysis and force
the end-of-packet commit.

Here's a simple example of the TCG generated for
0x004000b4:  0x7800c020 {       R0 = #0x1 }

BEFORE:
 ---- 004000b4
 movi_i32 new_r0,$0x1
 mov_i32 r0,new_r0

AFTER:
 ---- 004000b4
 movi_i32 r0,$0x1

This patch reintroduces a use of check_for_attrib, so we remove the
G_GNUC_UNUSED added earlier in this series.

Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Brian Cain <bcain@quicinc.com>
Message-Id: <20230427230012.3800327-12-tsimpson@quicinc.com>
2023-05-18 12:40:52 -07:00
Taylor Simpson
b9f0326bf7 Hexagon (target/hexagon) Mark registers as read during packet analysis
Have gen_analyze_funcs mark the registers that are read by the
instruction.  We also mark the implicit reads using instruction
attributes.

Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230427230012.3800327-11-tsimpson@quicinc.com>
2023-05-18 12:40:52 -07:00
Taylor Simpson
25e1d87d10 Hexagon (target/hexagon) Clean up pred_written usage
Only endloop instructions will conditionally write to a predicate.
When there is an endloop instruction, we preload the values into
new_pred_value.

The only place pred_written is needed is when HEX_DEBUG is on.

We remove the last use of check_for_attrib.  However, new uses will be
introduced later in this series, so we mark it with G_GNUC_UNUSED.

Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230427230012.3800327-9-tsimpson@quicinc.com>
2023-05-18 12:40:52 -07:00
Taylor Simpson
406c74f22d Hexagon (target/hexagon) Add v68 scalar instructions
The following instructions are added
    L2_loadw_aq
    L4_loadd_aq
    R6_release_at_vi
    R6_release_st_vi
    S2_storew_rl_at_vi
    S4_stored_rl_at_vi
    S2_storew_rl_st_vi
    S4_stored_rl_st_vi

The release instructions are nop's in qemu.  The others behave as
 loads/stores.

The encodings for these instructions changed some "don't care" bits
    L2_loadw_locked
    L4_loadd_locked
    S2_storew_locked
    S4_stored_locked

Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Anton Johansson <anjo@rev.ng>
Message-Id: <20230427224057.3766963-3-tsimpson@quicinc.com>
2023-05-18 12:40:51 -07:00
Richard Henderson
53b26d253c target/Hexagon: Finish conversion to tcg_gen_qemu_{ld, st}_*
Convert away from the old interface with the implicit
MemOp argument.  Importantly, this removes some incorrect
casts generated by idef-parser's gen_load().

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Anton Johansson <anjo@rev.ng>
Message-Id: <20230502135741.1158035-4-richard.henderson@linaro.org>
2023-05-05 17:05:28 +01:00
Taylor Simpson
2bda44e8aa Hexagon (target/hexagon) Merge arguments to probe_pkt_scalar_hvx_stores
Reducing the number of arguments reduces the overhead of the helper
call

Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230405164211.30015-2-tsimpson@quicinc.com>
2023-04-21 09:32:52 -07:00
Matheus Tavares Bernardino
bee1fc56c2 Hexagon (translate.c): avoid redundant PC updates on COF
When there is a conditional change of flow or an endloop instruction, we
preload HEX_REG_PC with ctx->next_PC at gen_start_packet(). Nonetheless,
we still generate TCG code to do this update again at gen_goto_tb() when
the condition for the COF is not met, thus producing redundant
instructions. This can be seen with the following packet:

 0x004002e4:  0x5c20d000 {       if (!P0) jump:t PC+0 }

Which generates this TCG code:

   ---- 004002e4
-> mov_i32 pc,$0x4002e8
   and_i32 loc9,p0,$0x1
   mov_i32 branch_taken,loc9
   add_i32 pkt_cnt,pkt_cnt,$0x2
   add_i32 insn_cnt,insn_cnt,$0x2
   brcond_i32 branch_taken,$0x0,ne,$L1
   goto_tb $0x0
   mov_i32 pc,$0x4002e4
   exit_tb $0x7fb0c36e5200
   set_label $L1
   goto_tb $0x1
-> mov_i32 pc,$0x4002e8
   exit_tb $0x7fb0c36e5201
   set_label $L0
   exit_tb $0x7fb0c36e5203

Note that even after optimizations, the redundant PC update is still
present:

   ---- 004002e4
-> mov_i32 pc,$0x4002e8                     sync: 0  dead: 0 1  pref=0xffff
   mov_i32 branch_taken,$0x1                sync: 0  dead: 0 1  pref=0xffff
   add_i32 pkt_cnt,pkt_cnt,$0x2             sync: 0  dead: 0 1  pref=0xffff
   add_i32 insn_cnt,insn_cnt,$0x2           sync: 0  dead: 0 1 2  pref=0xffff
   goto_tb $0x1
-> mov_i32 pc,$0x4002e8                     sync: 0  dead: 0 1  pref=0xffff
   exit_tb $0x7fb0c36e5201
   set_label $L0
   exit_tb $0x7fb0c36e5203

With this patch, the second redundant update is properly discarded.

Note that we need the additional "move_to_pc" flag instead of just
avoiding the update whenever `dest == ctx->next_PC`, as that could
potentially skip updates from a COF with met condition, whose
ctx->branch_dest just happens to be equal to ctx->next_PC.

Signed-off-by: Matheus Tavares Bernardino <quic_mathbern@quicinc.com>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Anton Johansson <anjo@rev.ng>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <fc059153c3f0526d97b7f13450c02b276b0908e1.1679519341.git.quic_mathbern@quicinc.com>
2023-04-21 09:32:51 -07:00
Taylor Simpson
c2b33d0be9 Hexagon (target/hexagon) Improve code gen for predicated HVX instructions
The following improvements are made for predicated HVX instructions
    During gen_commit_hvx, unconditionally move the "new" value into
        the dest
    Don't set slot_cancelled
    Remove runtime bookkeeping of which registers were updated
    Reduce the cases where gen_log_vreg_write[_pair] is called
        It's only needed for special operands VxxV and VyV
    Remove gen_log_qreg_write

Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Anton Johansson <anjo@rev.ng>
Message-Id: <20230307025828.1612809-15-tsimpson@quicinc.com>
2023-03-06 20:47:12 -08:00
Taylor Simpson
7b84fd04bd Hexagon (target/hexagon) Reduce manipulation of slot_cancelled
We only need to track slot for predicated stores and predicated HVX
instructions.

Add arguments to the probe helper functions to indicate if the slot
is predicated.

Here is a simple example of the differences in the TCG code generated:

IN:
0x00400094:  0xf900c102 {       if (P0) R2 = and(R0,R1) }

BEFORE
 ---- 00400094
 mov_i32 slot_cancelled,$0x0
 mov_i32 new_r2,r2
 and_i32 tmp0,p0,$0x1
 brcond_i32 tmp0,$0x0,eq,$L1
 and_i32 tmp0,r0,r1
 mov_i32 new_r2,tmp0
 br $L2
 set_label $L1
 or_i32 slot_cancelled,slot_cancelled,$0x8
 set_label $L2
 mov_i32 r2,new_r2

AFTER
 ---- 00400094
 mov_i32 new_r2,r2
 and_i32 tmp0,p0,$0x1
 brcond_i32 tmp0,$0x0,eq,$L1
 and_i32 tmp0,r0,r1
 mov_i32 new_r2,tmp0
 br $L2
 set_label $L1
 set_label $L2
 mov_i32 r2,new_r2

Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Anton Johansson <anjo@rev.ng>
Message-Id: <20230307025828.1612809-14-tsimpson@quicinc.com>
2023-03-06 20:47:12 -08:00
Taylor Simpson
4d6f84208c Hexagon (target/hexagon) Analyze packet for HVX
Extend the analyze_<tag> functions for HVX vector and predicate writes
Remove calls to ctx_log_vreg_write[_pair] from gen_tcg_funcs.py
During gen_start_packet, reload the predicated HVX registers into
    fugure_VRegs and tmp_VRegs

Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Anton Johansson <anjo@rev.ng>
Message-Id: <20230307025828.1612809-8-tsimpson@quicinc.com>
2023-03-06 20:47:12 -08:00
Taylor Simpson
4d13bb51d2 Hexagon (target/hexagon) Don't set pkt_has_store_s1 when not needed
The pkt_has_store_s1 field in CPUHexagonState is only needed in generated
helpers for scalar load instructions.  See check_noshuf and mem_load[1248]
in op_helper.c.

We add logic in gen_analyze_funcs.py to set need_pkt_has_store_s1 in
DisasContext when it is needed at runtime.

Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Anton Johansson <anjo@rev.ng>
Message-Id: <20230307025828.1612809-7-tsimpson@quicinc.com>
2023-03-06 20:47:12 -08:00
Taylor Simpson
10849c2623 Hexagon (target/hexagon) Analyze packet before generating TCG
We create a new generator that creates an analyze_<tag> function for
each instruction.  Currently, these functions record the writes to
R, P, and C registers by calling ctx_log_reg_write[_pair] or
ctx_log_pred_write.

During gen_start_packet, we invoke the analyze_<tag> function for
each instruction in the packet, and we mark the implicit register
and predicate writes.

Doing the analysis up front has several advantages
- We remove calls to ctx_log_* from gen_tcg_funcs.py and genptr.c
- After the analysis is performed, we can initialize hex_new_value
  for each of the predicated assignments rather than during TCG
  generation for the instructions
- This is a stepping stone for future work where the analysis will
  include the set of registers that are read.  In cases where
  the packet doesn't have an overlap between the registers that are
  written and registers that are read, we can avoid the intermediate
  step of writing to hex_new_value.  Note that other checks will also
  be needed (e.g., no instructions can raise an exception).

Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Anton Johansson <anjo@rev.ng>
Message-Id: <20230307025828.1612809-6-tsimpson@quicinc.com>
2023-03-06 20:47:12 -08:00
Richard Henderson
09538b08c4 target/hexagon: Drop tcg_temp_free from C code
Translators are no longer required to free tcg temporaries.

Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-03-05 13:44:07 -08:00
Richard Henderson
7a819de850 target/hexagon: Don't use tcg_temp_local_new_*
Since tcg_temp_new_* is now identical, use those.

Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-03-01 07:33:28 -10:00
Richard Henderson
597f9b2d30 accel/tcg: Pass max_insn to gen_intermediate_code by pointer
In preparation for returning the number of insns generated
via the same pointer.  Adjust only the prototypes so far.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-03-01 07:33:27 -10:00
Taylor Simpson
564b2040a6 Hexagon (target/hexagon) Use direct block chaining for tight loops
Direct block chaining is documented here
https://qemu.readthedocs.io/en/latest/devel/tcg.html#direct-block-chaining

Hexagon inner loops end with the endloop0 instruction
To go back to the beginning of the loop, this instructions writes to PC
from register SA0 (start address 0).  To use direct block chaining, we
have to assign PC with a constant value.  So, we specialize the code
generation when the start of the translation block is equal to SA0.

When this is the case, we defer the compare/branch from endloop0 to
gen_end_tb.  When this is done, we can assign the start address of the TB
to PC.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <20221108162906.3166-12-tsimpson@quicinc.com>
2022-12-16 10:10:28 -08:00
Taylor Simpson
1b9a7f2a13 Hexagon (target/hexagon) Use direct block chaining for direct jump/branch
Direct block chaining is documented here
https://qemu.readthedocs.io/en/latest/devel/tcg.html#direct-block-chaining

Recall that Hexagon allows packets with multiple jumps where only the
first one with a true predicate will actually jump.  We can  use
tcg_gen_goto_tb/tcg_gen_exit_tb when the packet contains a single
PC-relative branch or jump.  If not, we use tcg_gen_lookup_and_goto_ptr.

We add the following to DisasContext in order to delay the branching
until the end of packet commit (in gen_end_tb)
    branch_cond
        The TCGCond condition under which the branch is taken
        When branch_cond == TCG_COND_NEVER, there isn't a single
        direct branch in this packet.
        When branch_cond != TCG_COND_ALWAYS, the value is in
        hex_branch_taken
    branch_dest
        The destination of the branch

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <20221108162906.3166-11-tsimpson@quicinc.com>
2022-12-16 10:10:28 -08:00
Taylor Simpson
613653e500 Hexagon (target/hexagon) Remove next_PC from runtime state
The imported files don't properly mark all CONDEXEC instructions, so
we add some logic to hex_common.py to add the attribute.

Acked-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <20221108162906.3166-7-tsimpson@quicinc.com>
2022-12-16 10:10:28 -08:00
Taylor Simpson
40085901db Hexagon (target/hexagon) Remove PC from the runtime state
Add pc field to Packet structure
For helpers that need PC, pass an extra argument
Remove slot arg from conditional jump helpers
On a trap0, copy pkt->pc into hex_gpr[HEX_REG_PC]

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <20221108162906.3166-6-tsimpson@quicinc.com>
2022-12-16 10:10:28 -08:00
Taylor Simpson
fb67c2bf24 Hexagon (target/hexagon) Only use branch_taken when packet has multi cof
When a packet has more than one change-of-flow instruction, only the first
one to branch is considered.  We use the branch_taken variable to keep
track of this.

However, when there is a single cof instruction, we don't need the same
amount of bookkeeping.

We add the pkt_has_multi_cof member to the Packet structure, and pass this
information to the needed functions.

When there is a generated helper function with cof, the generator will
pass this pkt_has_multi_cof as a runtime value.

Acked-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <20221108162906.3166-5-tsimpson@quicinc.com>
2022-12-16 10:10:28 -08:00
Taylor Simpson
1e536334cc Hexagon (target/hexagon) Add pkt and insn to DisasContext
This enables us to reduce the number of parameters to many functions
In particular, the generated functions previously took all 3 as arguments

Not only does this simplify the code, it improves the translation time

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <20221108162906.3166-2-tsimpson@quicinc.com>
2022-12-16 10:10:28 -08:00
Taylor Simpson
661ad999c5 Hexagon (target/hexagon) move store size tracking to translation
The store width is needed for packet commit, so it is stored in
ctx->store_width.  Currently, it is set when a store has a TCG
override instead of a QEMU helper.  In the QEMU helper case, the
ctx->store_width is not set, we invoke a helper during packet commit
that uses the runtime store width.

This patch ensures ctx->store_width is set for all store instructions,
so performance is improved because packet commit can generate the proper
TCG store rather than the generic helper.

We do this by
- Use the attributes from the instructions during translation to
  set ctx->store_width
- Remove setting of ctx->store_width from genptr.c

Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220920080746.26791-3-tsimpson@quicinc.com>
2022-09-30 11:25:37 -07:00
Taylor Simpson
e2be9a5c5f Hexagon (target/hexagon) Change decision to set pkt_has_store_s[01]
We have found cases where pkt_has_store_s[01] is set incorrectly.
This leads to generating an unnecessary store that is left over
from a previous packet.

Add an attribute to determine if an instruction is a scalar store
The attribute is attached to the fSTORE macro (hex_common.py)
Update the logic in decode.c that sets pkt_has_store_s[01]

Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220920080746.26791-4-tsimpson@quicinc.com>
2022-09-30 11:25:37 -07:00