On 2/10/19, H.J. Lu <[email protected]> wrote:
> Emulate MMX packsswb/packssdw/packuswb with SSE packsswb/packssdw/packuswb
> plus moving bits 64:95 to bits 32:63 in SSE register. Only SSE register
> source operand is allowed.
>
> 2019-02-08 H.J. Lu <[email protected]>
> Uros Bizjak <[email protected]>
>
> PR target/89021
> * config/i386/i386-protos.h (ix86_move_vector_high_sse_to_mmx):
> New prototype.
> (ix86_split_mmx_pack): Likewise.
> * config/i386/i386.c (ix86_move_vector_high_sse_to_mmx): New
> function.
> (ix86_split_mmx_pack): Likewise.
> * config/i386/i386.md (mmx_isa): New.
> (enabled): Also check mmx_isa.
> * config/i386/mmx.md (any_s_truncate): New code iterator.
> (s_trunsuffix): New code attr.
> (mmx_packsswb): Removed.
> (mmx_packssdw): Likewise.
> (mmx_packuswb): Likewise.
> (mmx_pack<s_trunsuffix>swb): New define_insn_and_split to emulate
> MMX packsswb/packuswb with SSE2.
> (mmx_packssdw): Likewise.
LGTM, with a couple of nits below.
> ---
> gcc/config/i386/i386-protos.h | 3 ++
> gcc/config/i386/i386.c | 54 ++++++++++++++++++++++++++++
> gcc/config/i386/i386.md | 12 +++++++
> gcc/config/i386/mmx.md | 67 +++++++++++++++++++----------------
> 4 files changed, 106 insertions(+), 30 deletions(-)
>
> diff --git a/gcc/config/i386/i386-protos.h b/gcc/config/i386/i386-protos.h
> index 2d600173917..bb96a420a85 100644
> --- a/gcc/config/i386/i386-protos.h
> +++ b/gcc/config/i386/i386-protos.h
> @@ -200,6 +200,9 @@ extern void ix86_expand_vecop_qihi (enum rtx_code, rtx,
> rtx, rtx);
>
> extern rtx ix86_split_stack_guard (void);
>
> +extern void ix86_move_vector_high_sse_to_mmx (rtx);
> +extern void ix86_split_mmx_pack (rtx[], enum rtx_code);
> +
> #ifdef TREE_CODE
> extern void init_cumulative_args (CUMULATIVE_ARGS *, tree, rtx, tree,
> int);
> #endif /* TREE_CODE */
> diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
> index ba02c26c8b2..2af7f891350 100644
> --- a/gcc/config/i386/i386.c
> +++ b/gcc/config/i386/i386.c
> @@ -19955,6 +19955,60 @@ ix86_expand_vector_move_misalign (machine_mode
> mode, rtx operands[])
> gcc_unreachable ();
> }
>
> +/* Move bits 64:95 to bits 32:63. */
> +
> +void
> +ix86_move_vector_high_sse_to_mmx (rtx op)
> +{
> + rtx mask = gen_rtx_PARALLEL (VOIDmode,
> + gen_rtvec (4, GEN_INT (0), GEN_INT (2),
> + GEN_INT (0), GEN_INT (0)));
> + rtx dest = gen_rtx_REG (V4SImode, REGNO (op));
> + op = gen_rtx_VEC_SELECT (V4SImode, dest, mask);
> + rtx insn = gen_rtx_SET (dest, op);
> + emit_insn (insn);
> +}
> +
> +/* Split MMX pack with signed/unsigned saturation with SSE/SSE2. */
> +
> +void
> +ix86_split_mmx_pack (rtx operands[], enum rtx_code code)
> +{
> + rtx op0 = operands[0];
> + rtx op1 = operands[1];
> + rtx op2 = operands[2];
> +
> + machine_mode dmode = GET_MODE (op0);
> + machine_mode smode = GET_MODE (op1);
> + machine_mode inner_dmode = GET_MODE_INNER (dmode);
> + machine_mode inner_smode = GET_MODE_INNER (smode);
> +
> + /* Get the corresponding SSE mode for destination. */
> + int nunits = 16 / GET_MODE_SIZE (inner_dmode);
> + machine_mode sse_dmode = mode_for_vector (GET_MODE_INNER (dmode),
> + nunits).require ();
> + machine_mode sse_half_dmode = mode_for_vector (GET_MODE_INNER (dmode),
> + nunits / 2).require ();
> +
> + /* Get the corresponding SSE mode for source. */
> + nunits = 16 / GET_MODE_SIZE (inner_smode);
> + machine_mode sse_smode = mode_for_vector (GET_MODE_INNER (smode),
> + nunits).require ();
> +
> + /* Generate SSE pack with signed/unsigned saturation. */
> + rtx dest = gen_rtx_REG (sse_dmode, REGNO (op0));
> + op1 = gen_rtx_REG (sse_smode, REGNO (op1));
> + op2 = gen_rtx_REG (sse_smode, REGNO (op2));
> +
> + op1 = gen_rtx_fmt_e (code, sse_half_dmode, op1);
> + op2 = gen_rtx_fmt_e (code, sse_half_dmode, op2);
> + rtx insn = gen_rtx_SET (dest, gen_rtx_VEC_CONCAT (sse_dmode,
> + op1, op2));
> + emit_insn (insn);
> +
> + ix86_move_vector_high_sse_to_mmx (op0);
> +}
> +
> /* Helper function of ix86_fixup_binary_operands to canonicalize
> operand order. Returns true if the operands should be swapped. */
>
> diff --git a/gcc/config/i386/i386.md b/gcc/config/i386/i386.md
> index 4a32144a71a..72685107fc0 100644
> --- a/gcc/config/i386/i386.md
> +++ b/gcc/config/i386/i386.md
> @@ -792,6 +792,9 @@
> avx512vl,noavx512vl,x64_avx512dq,x64_avx512bw"
> (const_string "base"))
>
> +;; Define instruction set of MMX instructions
> +(define_attr "mmx_isa" "base,native,x64,x64_noavx,x64_avx" (const_string
> "base"))
> +
> (define_attr "enabled" ""
> (cond [(eq_attr "isa" "x64") (symbol_ref "TARGET_64BIT")
> (eq_attr "isa" "x64_sse2")
> @@ -830,6 +833,15 @@
> (eq_attr "isa" "noavx512dq") (symbol_ref "!TARGET_AVX512DQ")
> (eq_attr "isa" "avx512vl") (symbol_ref "TARGET_AVX512VL")
> (eq_attr "isa" "noavx512vl") (symbol_ref "!TARGET_AVX512VL")
> +
> + (eq_attr "mmx_isa" "native")
> + (symbol_ref "!TARGET_MMX_WITH_SSE")
> + (eq_attr "mmx_isa" "x64")
> + (symbol_ref "TARGET_MMX_WITH_SSE")
> + (eq_attr "mmx_isa" "x64_avx")
> + (symbol_ref "TARGET_MMX_WITH_SSE && TARGET_AVX")
> + (eq_attr "mmx_isa" "x64_noavx")
> + (symbol_ref "TARGET_MMX_WITH_SSE && !TARGET_AVX")
> ]
> (const_int 1)))
>
> diff --git a/gcc/config/i386/mmx.md b/gcc/config/i386/mmx.md
> index c1e0f2c411e..10096f7cab7 100644
> --- a/gcc/config/i386/mmx.md
> +++ b/gcc/config/i386/mmx.md
> @@ -58,6 +58,11 @@
> ;; Mapping from integer vector mode to mnemonic suffix
> (define_mode_attr mmxvecsize [(V8QI "b") (V4HI "w") (V2SI "d") (V1DI
> "q")])
>
> +;; Used in signed and unsigned truncations with saturation.
> +(define_code_iterator any_s_truncate [ss_truncate us_truncate])
> +;; Instruction suffix for truncations with saturation.
> +(define_code_attr s_trunsuffix [(ss_truncate "s") (us_truncate "u")])
Please move definitions that have single use nearby their usage site.
> +
> ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
> ;;
> ;; Move patterns
> @@ -1046,41 +1051,43 @@
> ;;
> ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
>
> -(define_insn "mmx_packsswb"
> - [(set (match_operand:V8QI 0 "register_operand" "=y")
> +(define_insn_and_split "mmx_pack<s_trunsuffix>swb"
> + [(set (match_operand:V8QI 0 "register_operand" "=y,x,Yv")
> (vec_concat:V8QI
> - (ss_truncate:V4QI
> - (match_operand:V4HI 1 "register_operand" "0"))
> - (ss_truncate:V4QI
> - (match_operand:V4HI 2 "nonimmediate_operand" "ym"))))]
> - "TARGET_MMX"
> - "packsswb\t{%2, %0|%0, %2}"
> - [(set_attr "type" "mmxshft")
> - (set_attr "mode" "DI")])
> + (any_s_truncate:V4QI
> + (match_operand:V4HI 1 "register_operand" "0,0,Yv"))
> + (any_s_truncate:V4QI
> + (match_operand:V4HI 2 "nonimmediate_operand" "ym,x,Yv"))))]
> + "TARGET_MMX || TARGET_MMX_WITH_SSE"
> + "@
> + pack<s_trunsuffix>swb\t{%2, %0|%0, %2}
> + #
> + #"
> + "&& reload_completed && TARGET_MMX_WITH_SSE"
The above should be without first &&, with "reload_completed" last. In
effect, the condition of the separate split pattern would read as:
"TARGET_MMX_WITH_SSE && reload_completed".
> + [(const_int 0)]
> + "ix86_split_mmx_pack (operands, <any_s_truncate:CODE>);"
> + [(set_attr "mmx_isa" "native,x64_noavx,x64_avx")
> + (set_attr "type" "mmxshft,sselog,sselog")
> + (set_attr "mode" "DI,TI,TI")])
>
> -(define_insn "mmx_packssdw"
> - [(set (match_operand:V4HI 0 "register_operand" "=y")
> +(define_insn_and_split "mmx_packssdw"
> + [(set (match_operand:V4HI 0 "register_operand" "=y,x,Yv")
> (vec_concat:V4HI
> (ss_truncate:V2HI
> - (match_operand:V2SI 1 "register_operand" "0"))
> + (match_operand:V2SI 1 "register_operand" "0,0,Yv"))
> (ss_truncate:V2HI
> - (match_operand:V2SI 2 "nonimmediate_operand" "ym"))))]
> - "TARGET_MMX"
> - "packssdw\t{%2, %0|%0, %2}"
> - [(set_attr "type" "mmxshft")
> - (set_attr "mode" "DI")])
> -
> -(define_insn "mmx_packuswb"
> - [(set (match_operand:V8QI 0 "register_operand" "=y")
> - (vec_concat:V8QI
> - (us_truncate:V4QI
> - (match_operand:V4HI 1 "register_operand" "0"))
> - (us_truncate:V4QI
> - (match_operand:V4HI 2 "nonimmediate_operand" "ym"))))]
> - "TARGET_MMX"
> - "packuswb\t{%2, %0|%0, %2}"
> - [(set_attr "type" "mmxshft")
> - (set_attr "mode" "DI")])
> + (match_operand:V2SI 2 "nonimmediate_operand" "ym,x,Yv"))))]
> + "TARGET_MMX || TARGET_MMX_WITH_SSE"
> + "@
> + packssdw\t{%2, %0|%0, %2}
> + #
> + #"
> + "&& reload_completed && TARGET_MMX_WITH_SSE"
Also here.
> + [(const_int 0)]
> + "ix86_split_mmx_pack (operands, SS_TRUNCATE);"
> + [(set_attr "mmx_isa" "native,x64_noavx,x64_avx")
> + (set_attr "type" "mmxshft,sselog,sselog")
> + (set_attr "mode" "DI,TI,TI")])
>
> (define_insn "mmx_punpckhbw"
> [(set (match_operand:V8QI 0 "register_operand" "=y")
> --
> 2.20.1
>
>
