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[v2,1/2] Genmatch: Support control flow graph case 1 for phi on condition

Message ID 20240905120047.3163255-1-pan2.li@intel.com
State New
Headers
Series [v2,1/2] Genmatch: Support control flow graph case 1 for phi on condition |

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Commit Message

Li, Pan2 Sept. 5, 2024, noon UTC 
  From: Pan Li <pan2.li@intel.com>

The gen_phi_on_cond can only support below control flow for cond
from day 1.  Aka:

+------+
| def  |
| ...  |       +-----+
| cond |------>| def |
+------+       | ... |
   |           +-----+
   |              |
   v              |
+-----+           |
| PHI |<----------+
+-----+

Unfortunately, there will be more scenarios of control flow on PHI.
For example as below:

T __attribute__((noinline))                            \
sat_s_add_##T##_fmt_3 (T x, T y)                       \
{                                                      \
  T sum;                                               \
  bool overflow = __builtin_add_overflow (x, y, &sum); \
  return overflow ? x < 0 ? MIN : MAX : sum;           \
}

DEF_SAT_S_ADD_FMT_3(int8_t, uint8_t, INT8_MIN, INT8_MAX)

With expanded RTL like below.
   3   │
   4   │ __attribute__((noinline))
   5   │ int8_t sat_s_add_int8_t_fmt_3 (int8_t x, int8_t y)
   6   │ {
   7   │   signed char _1;
   8   │   signed char _2;
   9   │   int8_t _3;
  10   │   __complex__ signed char _6;
  11   │   _Bool _8;
  12   │   signed char _9;
  13   │   signed char _10;
  14   │   signed char _11;
  15   │
  16   │ ;;   basic block 2, loop depth 0
  17   │ ;;    pred:       ENTRY
  18   │   _6 = .ADD_OVERFLOW (x_4(D), y_5(D));
  19   │   _2 = IMAGPART_EXPR <_6>;
  20   │   if (_2 != 0)
  21   │     goto <bb 4>; [50.00%]
  22   │   else
  23   │     goto <bb 3>; [50.00%]
  24   │ ;;    succ:       4
  25   │ ;;                3
  26   │
  27   │ ;;   basic block 3, loop depth 0
  28   │ ;;    pred:       2
  29   │   _1 = REALPART_EXPR <_6>;
  30   │   goto <bb 5>; [100.00%]
  31   │ ;;    succ:       5
  32   │
  33   │ ;;   basic block 4, loop depth 0
  34   │ ;;    pred:       2
  35   │   _8 = x_4(D) < 0;
  36   │   _9 = (signed char) _8;
  37   │   _10 = -_9;
  38   │   _11 = _10 ^ 127;
  39   │ ;;    succ:       5
  40   │
  41   │ ;;   basic block 5, loop depth 0
  42   │ ;;    pred:       3
  43   │ ;;                4
  44   │   # _3 = PHI <_1(3), _11(4)>
  45   │   return _3;
  46   │ ;;    succ:       EXIT
  47   │
  48   │ }

The above code will have below control flow which is not supported by
the gen_phi_on_cond.

+------+
| def  |
| ...  |       +-----+
| cond |------>| def |
+------+       | ... |
   |           +-----+
   |              |
   v              |
+-----+           |
| def |           |
| ... |           |
+-----+           |
   |              |
   |              |
   v              |
+-----+           |
| PHI |<----------+
+-----+

This patch would like to add support above control flow for the
gen_phi_on_cond.  The generated match code looks like below.

Before this patch:
basic_block _b1 = gimple_bb (_a1);
if (gimple_phi_num_args (_a1) == 2)
  {
    basic_block _pb_0_1 = EDGE_PRED (_b1, 0)->src;
    basic_block _pb_1_1 = EDGE_PRED (_b1, 1)->src;
    basic_block _db_1 = safe_dyn_cast <gcond *> (*gsi_last_bb (_pb_0_1)) ? _pb_0_1 : _pb_1_1;
    basic_block _other_db_1 = safe_dyn_cast <gcond *> (*gsi_last_bb (_pb_0_1)) ? _pb_1_1 : _pb_0_1;
    gcond *_ct_1 = safe_dyn_cast <gcond *> (*gsi_last_bb (_db_1));
    if (_ct_1 && EDGE_COUNT (_other_db_1->preds) == 1
      && EDGE_COUNT (_other_db_1->succs) == 1
      && EDGE_PRED (_other_db_1, 0)->src == _db_1)
      {
...

After this patch:
basic_block _b1 = gimple_bb (_a1);
basic_block _b_cond_1;
if (gimple_phi_num_args (_a1) == 2
    && (control_flow_graph_case_0_match (_b1, &_b_cond_1)
        || control_flow_graph_case_1_match (_b1, &_b_cond_1)))
    {
...

The below testsuites are passed for this patch:
* The rv64gcv fully regression test.
* The x86 bootstrap test.
* The x86 fully regression test.

gcc/ChangeLog:

	* genmatch.cc (dt_operand::gen_phi_on_cond): Add support control
	flow graph case 1 for gen phi on condition.
	* gimple-match-head.cc (control_flow_graph_case_0_match): Add
	new func impl to match case 0 of cfg.
	(control_flow_graph_case_1_match): Ditto but for case 1.

Signed-off-by: Pan Li <pan2.li@intel.com>
---
 gcc/genmatch.cc          |  37 +++++--------
 gcc/gimple-match-head.cc | 115 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 130 insertions(+), 22 deletions(-)

Comments

Richard Biener Sept. 9, 2024, 12:26 p.m. UTC | #1 
On Thu, Sep 5, 2024 at 2:01 PM <pan2.li@intel.com> wrote:
>
> From: Pan Li <pan2.li@intel.com>
>
> The gen_phi_on_cond can only support below control flow for cond
> from day 1.  Aka:
>
> +------+
> | def  |
> | ...  |       +-----+
> | cond |------>| def |
> +------+       | ... |
>    |           +-----+
>    |              |
>    v              |
> +-----+           |
> | PHI |<----------+
> +-----+
>
> Unfortunately, there will be more scenarios of control flow on PHI.
> For example as below:
>
> T __attribute__((noinline))                            \
> sat_s_add_##T##_fmt_3 (T x, T y)                       \
> {                                                      \
>   T sum;                                               \
>   bool overflow = __builtin_add_overflow (x, y, &sum); \
>   return overflow ? x < 0 ? MIN : MAX : sum;           \
> }
>
> DEF_SAT_S_ADD_FMT_3(int8_t, uint8_t, INT8_MIN, INT8_MAX)
>
> With expanded RTL like below.
>    3   │
>    4   │ __attribute__((noinline))
>    5   │ int8_t sat_s_add_int8_t_fmt_3 (int8_t x, int8_t y)
>    6   │ {
>    7   │   signed char _1;
>    8   │   signed char _2;
>    9   │   int8_t _3;
>   10   │   __complex__ signed char _6;
>   11   │   _Bool _8;
>   12   │   signed char _9;
>   13   │   signed char _10;
>   14   │   signed char _11;
>   15   │
>   16   │ ;;   basic block 2, loop depth 0
>   17   │ ;;    pred:       ENTRY
>   18   │   _6 = .ADD_OVERFLOW (x_4(D), y_5(D));
>   19   │   _2 = IMAGPART_EXPR <_6>;
>   20   │   if (_2 != 0)
>   21   │     goto <bb 4>; [50.00%]
>   22   │   else
>   23   │     goto <bb 3>; [50.00%]
>   24   │ ;;    succ:       4
>   25   │ ;;                3
>   26   │
>   27   │ ;;   basic block 3, loop depth 0
>   28   │ ;;    pred:       2
>   29   │   _1 = REALPART_EXPR <_6>;
>   30   │   goto <bb 5>; [100.00%]
>   31   │ ;;    succ:       5
>   32   │
>   33   │ ;;   basic block 4, loop depth 0
>   34   │ ;;    pred:       2
>   35   │   _8 = x_4(D) < 0;
>   36   │   _9 = (signed char) _8;
>   37   │   _10 = -_9;
>   38   │   _11 = _10 ^ 127;
>   39   │ ;;    succ:       5
>   40   │
>   41   │ ;;   basic block 5, loop depth 0
>   42   │ ;;    pred:       3
>   43   │ ;;                4
>   44   │   # _3 = PHI <_1(3), _11(4)>
>   45   │   return _3;
>   46   │ ;;    succ:       EXIT
>   47   │
>   48   │ }
>
> The above code will have below control flow which is not supported by
> the gen_phi_on_cond.
>
> +------+
> | def  |
> | ...  |       +-----+
> | cond |------>| def |
> +------+       | ... |
>    |           +-----+
>    |              |
>    v              |
> +-----+           |
> | def |           |
> | ... |           |
> +-----+           |
>    |              |
>    |              |
>    v              |
> +-----+           |
> | PHI |<----------+
> +-----+
>
> This patch would like to add support above control flow for the
> gen_phi_on_cond.  The generated match code looks like below.
>
> Before this patch:
> basic_block _b1 = gimple_bb (_a1);
> if (gimple_phi_num_args (_a1) == 2)
>   {
>     basic_block _pb_0_1 = EDGE_PRED (_b1, 0)->src;
>     basic_block _pb_1_1 = EDGE_PRED (_b1, 1)->src;
>     basic_block _db_1 = safe_dyn_cast <gcond *> (*gsi_last_bb (_pb_0_1)) ? _pb_0_1 : _pb_1_1;
>     basic_block _other_db_1 = safe_dyn_cast <gcond *> (*gsi_last_bb (_pb_0_1)) ? _pb_1_1 : _pb_0_1;
>     gcond *_ct_1 = safe_dyn_cast <gcond *> (*gsi_last_bb (_db_1));
>     if (_ct_1 && EDGE_COUNT (_other_db_1->preds) == 1
>       && EDGE_COUNT (_other_db_1->succs) == 1
>       && EDGE_PRED (_other_db_1, 0)->src == _db_1)
>       {
> ...
>
> After this patch:
> basic_block _b1 = gimple_bb (_a1);
> basic_block _b_cond_1;
> if (gimple_phi_num_args (_a1) == 2
>     && (control_flow_graph_case_0_match (_b1, &_b_cond_1)
>         || control_flow_graph_case_1_match (_b1, &_b_cond_1)))
>     {
> ...
>
> The below testsuites are passed for this patch:
> * The rv64gcv fully regression test.
> * The x86 bootstrap test.
> * The x86 fully regression test.

Sorry to spoil this again, but can you instead create an interface like

gcond *
match_cond_with_phi (gphi *phi, tree *true_arg, tree *false_arg);

That would from a PHI node match up the controlling condition and
initialize {true,false}_arg with the PHI args that match the conditions
true/false case?

I also think for the diamond case you fail to identify the appropriate
true/false PHI argument since both incoming edges are not from the
condition block they won't have EDGE_{TRUE,FALSE}_VALUE set.

Richard.

> gcc/ChangeLog:
>
>         * genmatch.cc (dt_operand::gen_phi_on_cond): Add support control
>         flow graph case 1 for gen phi on condition.
>         * gimple-match-head.cc (control_flow_graph_case_0_match): Add
>         new func impl to match case 0 of cfg.
>         (control_flow_graph_case_1_match): Ditto but for case 1.
>
> Signed-off-by: Pan Li <pan2.li@intel.com>
> ---
>  gcc/genmatch.cc          |  37 +++++--------
>  gcc/gimple-match-head.cc | 115 +++++++++++++++++++++++++++++++++++++++
>  2 files changed, 130 insertions(+), 22 deletions(-)
>
> diff --git a/gcc/genmatch.cc b/gcc/genmatch.cc
> index a56bd90cb2c..e0ec1c0e928 100644
> --- a/gcc/genmatch.cc
> +++ b/gcc/genmatch.cc
> @@ -3518,43 +3518,36 @@ dt_operand::gen_phi_on_cond (FILE *f, int indent, int depth)
>  {
>    fprintf_indent (f, indent,
>      "basic_block _b%d = gimple_bb (_a%d);\n", depth, depth);
> +  fprintf_indent (f, indent, "basic_block _b_cond_%d;\n", depth);
>
> -  fprintf_indent (f, indent, "if (gimple_phi_num_args (_a%d) == 2)\n", depth);
> +  fprintf_indent (f, indent, "if (gimple_phi_num_args (_a%d) == 2\n", depth);
>
> -  indent += 2;
> -  fprintf_indent (f, indent, "{\n");
>    indent += 2;
>
>    fprintf_indent (f, indent,
> -    "basic_block _pb_0_%d = EDGE_PRED (_b%d, 0)->src;\n", depth, depth);
> -  fprintf_indent (f, indent,
> -    "basic_block _pb_1_%d = EDGE_PRED (_b%d, 1)->src;\n", depth, depth);
> -  fprintf_indent (f, indent,
> -    "basic_block _db_%d = safe_dyn_cast <gcond *> (*gsi_last_bb (_pb_0_%d)) ? "
> -    "_pb_0_%d : _pb_1_%d;\n", depth, depth, depth, depth);
> +    "  && (control_flow_graph_case_0_match (_b%d, &_b_cond_%d)\n",
> +    depth, depth);
>    fprintf_indent (f, indent,
> -    "basic_block _other_db_%d = safe_dyn_cast <gcond *> "
> -    "(*gsi_last_bb (_pb_0_%d)) ? _pb_1_%d : _pb_0_%d;\n",
> -    depth, depth, depth, depth);
> +    "      || control_flow_graph_case_1_match (_b%d, &_b_cond_%d)))\n",
> +    depth, depth);
> +
> +  indent += 2;
> +  fprintf_indent (f, indent, "{\n");
> +  indent += 2;
>
>    fprintf_indent (f, indent,
> -    "gcond *_ct_%d = safe_dyn_cast <gcond *> (*gsi_last_bb (_db_%d));\n",
> +    "gcond *_cond_%d = safe_dyn_cast <gcond *> (*gsi_last_bb (_b_cond_%d));\n",
>      depth, depth);
> -  fprintf_indent (f, indent, "if (_ct_%d"
> -    " && EDGE_COUNT (_other_db_%d->preds) == 1\n", depth, depth);
> -  fprintf_indent (f, indent,
> -    "  && EDGE_COUNT (_other_db_%d->succs) == 1\n", depth);
> -  fprintf_indent (f, indent,
> -    "  && EDGE_PRED (_other_db_%d, 0)->src == _db_%d)\n", depth, depth);
> +  fprintf_indent (f, indent, "if (_cond_%d)\n", depth);
>
>    indent += 2;
>    fprintf_indent (f, indent, "{\n");
>    indent += 2;
>
>    fprintf_indent (f, indent,
> -    "tree _cond_lhs_%d = gimple_cond_lhs (_ct_%d);\n", depth, depth);
> +    "tree _cond_lhs_%d = gimple_cond_lhs (_cond_%d);\n", depth, depth);
>    fprintf_indent (f, indent,
> -    "tree _cond_rhs_%d = gimple_cond_rhs (_ct_%d);\n", depth, depth);
> +    "tree _cond_rhs_%d = gimple_cond_rhs (_cond_%d);\n", depth, depth);
>
>    char opname_0[20];
>    char opname_1[20];
> @@ -3562,7 +3555,7 @@ dt_operand::gen_phi_on_cond (FILE *f, int indent, int depth)
>    gen_opname (opname_0, 0);
>
>    fprintf_indent (f, indent,
> -    "tree %s = build2 (gimple_cond_code (_ct_%d), "
> +    "tree %s = build2 (gimple_cond_code (_cond_%d), "
>      "boolean_type_node, _cond_lhs_%d, _cond_rhs_%d);\n",
>      opname_0, depth, depth, depth);
>
> diff --git a/gcc/gimple-match-head.cc b/gcc/gimple-match-head.cc
> index 924d3f1e710..eb43e5c58cb 100644
> --- a/gcc/gimple-match-head.cc
> +++ b/gcc/gimple-match-head.cc
> @@ -375,3 +375,118 @@ gimple_bitwise_inverted_equal_p (tree expr1, tree expr2, bool &wascmp, tree (*va
>      return true;
>    return false;
>  }
> +
> +/*
> + * Return TRUE if the cfg matches the below layout by the given b2 in
> + * the first argument.  Or return FALSE.
> + *
> + * If return TRUE, the output argument b_out will be updated to the b0
> + * block as below example.
> + *
> + * If return FALSE, the output argument b_out will be NULL_BLOCK.
> + *
> + *    |
> + *    |
> + *    v
> + * +------+
> + * | b0:  |
> + * | def  |       +-----+
> + * | ...  |       | b1: |
> + * | cond |------>| def |
> + * +------+       | ... |
> + *    |           +-----+
> + *    |              |
> + *    v              |
> + * +-----+           |
> + * | b2: |           |
> + * | def |<----------+
> + * +-----+
> + */
> +static inline bool
> +control_flow_graph_case_0_match (basic_block b2, basic_block *b_out)
> +{
> +  *b_out = NULL;
> +
> +  if (EDGE_COUNT (b2->preds) != 2)
> +    return false;
> +
> +  basic_block pred_0 = EDGE_PRED (b2, 0)->src;
> +  basic_block pred_1 = EDGE_PRED (b2, 1)->src;
> +
> +  if (pred_0 == NULL || pred_1 == NULL)
> +    return false;
> +
> +  if (!(EDGE_COUNT (pred_0->succs) == 2 && EDGE_COUNT (pred_1->succs) == 1)
> +     && !(EDGE_COUNT (pred_0->succs) == 1 && EDGE_COUNT (pred_1->succs) == 2))
> +    return false;
> +
> +  basic_block b0 = EDGE_COUNT (pred_0->succs) == 2 ? pred_0 : pred_1;
> +  basic_block b1 = EDGE_COUNT (pred_0->succs) == 1 ? pred_0 : pred_1;
> +
> +  if (EDGE_COUNT (b1->preds) != 1 || EDGE_PRED (b1, 0)->src != b0)
> +    return false;
> +
> +  *b_out = b0;
> +  return true;
> +}
> +
> +/*
> + * Return TRUE if the cfg matches the below layout by the given b3 in
> + * the first argument.  Or return FALSE.
> + *
> + * If return TRUE, the output argument b_out will be updated to the b0
> + * block as below example.
> + *
> + * If return FALSE, the output argument b_out will be NULL.
> + *
> + *    |
> + *    |
> + *    v
> + * +------+
> + * | b0:  |
> + * | ...  |       +-----+
> + * | cond |------>| b2: |
> + * +------+       | ... |
> + *    |           +-----+
> + *    |              |
> + *    v              |
> + * +-----+           |
> + * | b1: |           |
> + * | ... |           |
> + * +-----+           |
> + *    |              |
> + *    |              |
> + *    v              |
> + * +-----+           |
> + * | b3: |<----------+
> + * | ... |
> + * +-----+
> + */
> +static inline bool
> +control_flow_graph_case_1_match (basic_block b3, basic_block *b_out)
> +{
> +  *b_out = NULL;
> +
> +  if (EDGE_COUNT (b3->preds) != 2)
> +    return false;
> +
> +  basic_block b1 = EDGE_PRED (b3, 0)->src;
> +  basic_block b2 = EDGE_PRED (b3, 1)->src;
> +
> +  if (b1 == NULL || b2 == NULL)
> +    return false;
> +
> +  if (EDGE_COUNT (b1->succs) != 1
> +      || EDGE_COUNT (b1->preds) != 1
> +      || EDGE_COUNT (b2->succs) != 1
> +      || EDGE_COUNT (b2->preds) != 1)
> +    return false;
> +
> +  basic_block b0 = EDGE_PRED (b1, 0)->src;
> +
> +  if (EDGE_COUNT (b0->succs) != 2 || EDGE_PRED (b2, 0)->src != b0)
> +    return false;
> +
> +  *b_out = b0;
> +  return true;
> +}
> --
> 2.43.0
>
Li, Pan2 Sept. 9, 2024, 10:50 p.m. UTC | #2 
Thanks Richard for comments.

> Sorry to spoil this again, but can you instead create an interface like

Need mind, let me update it.

> gcond *
> match_cond_with_phi (gphi *phi, tree *true_arg, tree *false_arg);

> That would from a PHI node match up the controlling condition and
> initialize {true,false}_arg with the PHI args that match the conditions
> true/false case?

> I also think for the diamond case you fail to identify the appropriate
> true/false PHI argument since both incoming edges are not from the
> condition block they won't have EDGE_{TRUE,FALSE}_VALUE set.

Sure thing, I also noticed that in form 4 the both edge of PHI are false, thus
I am working on another patch like extract_true_false_args_from_binary_phi
to take care of this. Let me append that patch to the series v3.

Pan

-----Original Message-----
From: Richard Biener <richard.guenther@gmail.com> 
Sent: Monday, September 9, 2024 8:27 PM
To: Li, Pan2 <pan2.li@intel.com>
Cc: gcc-patches@gcc.gnu.org; Tamar.Christina@arm.com; juzhe.zhong@rivai.ai; kito.cheng@gmail.com; jeffreyalaw@gmail.com; rdapp.gcc@gmail.com
Subject: Re: [PATCH v2 1/2] Genmatch: Support control flow graph case 1 for phi on condition

On Thu, Sep 5, 2024 at 2:01 PM <pan2.li@intel.com> wrote:
>
> From: Pan Li <pan2.li@intel.com>
>
> The gen_phi_on_cond can only support below control flow for cond
> from day 1.  Aka:
>
> +------+
> | def  |
> | ...  |       +-----+
> | cond |------>| def |
> +------+       | ... |
>    |           +-----+
>    |              |
>    v              |
> +-----+           |
> | PHI |<----------+
> +-----+
>
> Unfortunately, there will be more scenarios of control flow on PHI.
> For example as below:
>
> T __attribute__((noinline))                            \
> sat_s_add_##T##_fmt_3 (T x, T y)                       \
> {                                                      \
>   T sum;                                               \
>   bool overflow = __builtin_add_overflow (x, y, &sum); \
>   return overflow ? x < 0 ? MIN : MAX : sum;           \
> }
>
> DEF_SAT_S_ADD_FMT_3(int8_t, uint8_t, INT8_MIN, INT8_MAX)
>
> With expanded RTL like below.
>    3   │
>    4   │ __attribute__((noinline))
>    5   │ int8_t sat_s_add_int8_t_fmt_3 (int8_t x, int8_t y)
>    6   │ {
>    7   │   signed char _1;
>    8   │   signed char _2;
>    9   │   int8_t _3;
>   10   │   __complex__ signed char _6;
>   11   │   _Bool _8;
>   12   │   signed char _9;
>   13   │   signed char _10;
>   14   │   signed char _11;
>   15   │
>   16   │ ;;   basic block 2, loop depth 0
>   17   │ ;;    pred:       ENTRY
>   18   │   _6 = .ADD_OVERFLOW (x_4(D), y_5(D));
>   19   │   _2 = IMAGPART_EXPR <_6>;
>   20   │   if (_2 != 0)
>   21   │     goto <bb 4>; [50.00%]
>   22   │   else
>   23   │     goto <bb 3>; [50.00%]
>   24   │ ;;    succ:       4
>   25   │ ;;                3
>   26   │
>   27   │ ;;   basic block 3, loop depth 0
>   28   │ ;;    pred:       2
>   29   │   _1 = REALPART_EXPR <_6>;
>   30   │   goto <bb 5>; [100.00%]
>   31   │ ;;    succ:       5
>   32   │
>   33   │ ;;   basic block 4, loop depth 0
>   34   │ ;;    pred:       2
>   35   │   _8 = x_4(D) < 0;
>   36   │   _9 = (signed char) _8;
>   37   │   _10 = -_9;
>   38   │   _11 = _10 ^ 127;
>   39   │ ;;    succ:       5
>   40   │
>   41   │ ;;   basic block 5, loop depth 0
>   42   │ ;;    pred:       3
>   43   │ ;;                4
>   44   │   # _3 = PHI <_1(3), _11(4)>
>   45   │   return _3;
>   46   │ ;;    succ:       EXIT
>   47   │
>   48   │ }
>
> The above code will have below control flow which is not supported by
> the gen_phi_on_cond.
>
> +------+
> | def  |
> | ...  |       +-----+
> | cond |------>| def |
> +------+       | ... |
>    |           +-----+
>    |              |
>    v              |
> +-----+           |
> | def |           |
> | ... |           |
> +-----+           |
>    |              |
>    |              |
>    v              |
> +-----+           |
> | PHI |<----------+
> +-----+
>
> This patch would like to add support above control flow for the
> gen_phi_on_cond.  The generated match code looks like below.
>
> Before this patch:
> basic_block _b1 = gimple_bb (_a1);
> if (gimple_phi_num_args (_a1) == 2)
>   {
>     basic_block _pb_0_1 = EDGE_PRED (_b1, 0)->src;
>     basic_block _pb_1_1 = EDGE_PRED (_b1, 1)->src;
>     basic_block _db_1 = safe_dyn_cast <gcond *> (*gsi_last_bb (_pb_0_1)) ? _pb_0_1 : _pb_1_1;
>     basic_block _other_db_1 = safe_dyn_cast <gcond *> (*gsi_last_bb (_pb_0_1)) ? _pb_1_1 : _pb_0_1;
>     gcond *_ct_1 = safe_dyn_cast <gcond *> (*gsi_last_bb (_db_1));
>     if (_ct_1 && EDGE_COUNT (_other_db_1->preds) == 1
>       && EDGE_COUNT (_other_db_1->succs) == 1
>       && EDGE_PRED (_other_db_1, 0)->src == _db_1)
>       {
> ...
>
> After this patch:
> basic_block _b1 = gimple_bb (_a1);
> basic_block _b_cond_1;
> if (gimple_phi_num_args (_a1) == 2
>     && (control_flow_graph_case_0_match (_b1, &_b_cond_1)
>         || control_flow_graph_case_1_match (_b1, &_b_cond_1)))
>     {
> ...
>
> The below testsuites are passed for this patch:
> * The rv64gcv fully regression test.
> * The x86 bootstrap test.
> * The x86 fully regression test.

Sorry to spoil this again, but can you instead create an interface like

gcond *
match_cond_with_phi (gphi *phi, tree *true_arg, tree *false_arg);

That would from a PHI node match up the controlling condition and
initialize {true,false}_arg with the PHI args that match the conditions
true/false case?

I also think for the diamond case you fail to identify the appropriate
true/false PHI argument since both incoming edges are not from the
condition block they won't have EDGE_{TRUE,FALSE}_VALUE set.

Richard.

> gcc/ChangeLog:
>
>         * genmatch.cc (dt_operand::gen_phi_on_cond): Add support control
>         flow graph case 1 for gen phi on condition.
>         * gimple-match-head.cc (control_flow_graph_case_0_match): Add
>         new func impl to match case 0 of cfg.
>         (control_flow_graph_case_1_match): Ditto but for case 1.
>
> Signed-off-by: Pan Li <pan2.li@intel.com>
> ---
>  gcc/genmatch.cc          |  37 +++++--------
>  gcc/gimple-match-head.cc | 115 +++++++++++++++++++++++++++++++++++++++
>  2 files changed, 130 insertions(+), 22 deletions(-)
>
> diff --git a/gcc/genmatch.cc b/gcc/genmatch.cc
> index a56bd90cb2c..e0ec1c0e928 100644
> --- a/gcc/genmatch.cc
> +++ b/gcc/genmatch.cc
> @@ -3518,43 +3518,36 @@ dt_operand::gen_phi_on_cond (FILE *f, int indent, int depth)
>  {
>    fprintf_indent (f, indent,
>      "basic_block _b%d = gimple_bb (_a%d);\n", depth, depth);
> +  fprintf_indent (f, indent, "basic_block _b_cond_%d;\n", depth);
>
> -  fprintf_indent (f, indent, "if (gimple_phi_num_args (_a%d) == 2)\n", depth);
> +  fprintf_indent (f, indent, "if (gimple_phi_num_args (_a%d) == 2\n", depth);
>
> -  indent += 2;
> -  fprintf_indent (f, indent, "{\n");
>    indent += 2;
>
>    fprintf_indent (f, indent,
> -    "basic_block _pb_0_%d = EDGE_PRED (_b%d, 0)->src;\n", depth, depth);
> -  fprintf_indent (f, indent,
> -    "basic_block _pb_1_%d = EDGE_PRED (_b%d, 1)->src;\n", depth, depth);
> -  fprintf_indent (f, indent,
> -    "basic_block _db_%d = safe_dyn_cast <gcond *> (*gsi_last_bb (_pb_0_%d)) ? "
> -    "_pb_0_%d : _pb_1_%d;\n", depth, depth, depth, depth);
> +    "  && (control_flow_graph_case_0_match (_b%d, &_b_cond_%d)\n",
> +    depth, depth);
>    fprintf_indent (f, indent,
> -    "basic_block _other_db_%d = safe_dyn_cast <gcond *> "
> -    "(*gsi_last_bb (_pb_0_%d)) ? _pb_1_%d : _pb_0_%d;\n",
> -    depth, depth, depth, depth);
> +    "      || control_flow_graph_case_1_match (_b%d, &_b_cond_%d)))\n",
> +    depth, depth);
> +
> +  indent += 2;
> +  fprintf_indent (f, indent, "{\n");
> +  indent += 2;
>
>    fprintf_indent (f, indent,
> -    "gcond *_ct_%d = safe_dyn_cast <gcond *> (*gsi_last_bb (_db_%d));\n",
> +    "gcond *_cond_%d = safe_dyn_cast <gcond *> (*gsi_last_bb (_b_cond_%d));\n",
>      depth, depth);
> -  fprintf_indent (f, indent, "if (_ct_%d"
> -    " && EDGE_COUNT (_other_db_%d->preds) == 1\n", depth, depth);
> -  fprintf_indent (f, indent,
> -    "  && EDGE_COUNT (_other_db_%d->succs) == 1\n", depth);
> -  fprintf_indent (f, indent,
> -    "  && EDGE_PRED (_other_db_%d, 0)->src == _db_%d)\n", depth, depth);
> +  fprintf_indent (f, indent, "if (_cond_%d)\n", depth);
>
>    indent += 2;
>    fprintf_indent (f, indent, "{\n");
>    indent += 2;
>
>    fprintf_indent (f, indent,
> -    "tree _cond_lhs_%d = gimple_cond_lhs (_ct_%d);\n", depth, depth);
> +    "tree _cond_lhs_%d = gimple_cond_lhs (_cond_%d);\n", depth, depth);
>    fprintf_indent (f, indent,
> -    "tree _cond_rhs_%d = gimple_cond_rhs (_ct_%d);\n", depth, depth);
> +    "tree _cond_rhs_%d = gimple_cond_rhs (_cond_%d);\n", depth, depth);
>
>    char opname_0[20];
>    char opname_1[20];
> @@ -3562,7 +3555,7 @@ dt_operand::gen_phi_on_cond (FILE *f, int indent, int depth)
>    gen_opname (opname_0, 0);
>
>    fprintf_indent (f, indent,
> -    "tree %s = build2 (gimple_cond_code (_ct_%d), "
> +    "tree %s = build2 (gimple_cond_code (_cond_%d), "
>      "boolean_type_node, _cond_lhs_%d, _cond_rhs_%d);\n",
>      opname_0, depth, depth, depth);
>
> diff --git a/gcc/gimple-match-head.cc b/gcc/gimple-match-head.cc
> index 924d3f1e710..eb43e5c58cb 100644
> --- a/gcc/gimple-match-head.cc
> +++ b/gcc/gimple-match-head.cc
> @@ -375,3 +375,118 @@ gimple_bitwise_inverted_equal_p (tree expr1, tree expr2, bool &wascmp, tree (*va
>      return true;
>    return false;
>  }
> +
> +/*
> + * Return TRUE if the cfg matches the below layout by the given b2 in
> + * the first argument.  Or return FALSE.
> + *
> + * If return TRUE, the output argument b_out will be updated to the b0
> + * block as below example.
> + *
> + * If return FALSE, the output argument b_out will be NULL_BLOCK.
> + *
> + *    |
> + *    |
> + *    v
> + * +------+
> + * | b0:  |
> + * | def  |       +-----+
> + * | ...  |       | b1: |
> + * | cond |------>| def |
> + * +------+       | ... |
> + *    |           +-----+
> + *    |              |
> + *    v              |
> + * +-----+           |
> + * | b2: |           |
> + * | def |<----------+
> + * +-----+
> + */
> +static inline bool
> +control_flow_graph_case_0_match (basic_block b2, basic_block *b_out)
> +{
> +  *b_out = NULL;
> +
> +  if (EDGE_COUNT (b2->preds) != 2)
> +    return false;
> +
> +  basic_block pred_0 = EDGE_PRED (b2, 0)->src;
> +  basic_block pred_1 = EDGE_PRED (b2, 1)->src;
> +
> +  if (pred_0 == NULL || pred_1 == NULL)
> +    return false;
> +
> +  if (!(EDGE_COUNT (pred_0->succs) == 2 && EDGE_COUNT (pred_1->succs) == 1)
> +     && !(EDGE_COUNT (pred_0->succs) == 1 && EDGE_COUNT (pred_1->succs) == 2))
> +    return false;
> +
> +  basic_block b0 = EDGE_COUNT (pred_0->succs) == 2 ? pred_0 : pred_1;
> +  basic_block b1 = EDGE_COUNT (pred_0->succs) == 1 ? pred_0 : pred_1;
> +
> +  if (EDGE_COUNT (b1->preds) != 1 || EDGE_PRED (b1, 0)->src != b0)
> +    return false;
> +
> +  *b_out = b0;
> +  return true;
> +}
> +
> +/*
> + * Return TRUE if the cfg matches the below layout by the given b3 in
> + * the first argument.  Or return FALSE.
> + *
> + * If return TRUE, the output argument b_out will be updated to the b0
> + * block as below example.
> + *
> + * If return FALSE, the output argument b_out will be NULL.
> + *
> + *    |
> + *    |
> + *    v
> + * +------+
> + * | b0:  |
> + * | ...  |       +-----+
> + * | cond |------>| b2: |
> + * +------+       | ... |
> + *    |           +-----+
> + *    |              |
> + *    v              |
> + * +-----+           |
> + * | b1: |           |
> + * | ... |           |
> + * +-----+           |
> + *    |              |
> + *    |              |
> + *    v              |
> + * +-----+           |
> + * | b3: |<----------+
> + * | ... |
> + * +-----+
> + */
> +static inline bool
> +control_flow_graph_case_1_match (basic_block b3, basic_block *b_out)
> +{
> +  *b_out = NULL;
> +
> +  if (EDGE_COUNT (b3->preds) != 2)
> +    return false;
> +
> +  basic_block b1 = EDGE_PRED (b3, 0)->src;
> +  basic_block b2 = EDGE_PRED (b3, 1)->src;
> +
> +  if (b1 == NULL || b2 == NULL)
> +    return false;
> +
> +  if (EDGE_COUNT (b1->succs) != 1
> +      || EDGE_COUNT (b1->preds) != 1
> +      || EDGE_COUNT (b2->succs) != 1
> +      || EDGE_COUNT (b2->preds) != 1)
> +    return false;
> +
> +  basic_block b0 = EDGE_PRED (b1, 0)->src;
> +
> +  if (EDGE_COUNT (b0->succs) != 2 || EDGE_PRED (b2, 0)->src != b0)
> +    return false;
> +
> +  *b_out = b0;
> +  return true;
> +}
> --
> 2.43.0
>
diff mbox series

Patch

diff --git a/gcc/genmatch.cc b/gcc/genmatch.cc
index a56bd90cb2c..e0ec1c0e928 100644
--- a/gcc/genmatch.cc
+++ b/gcc/genmatch.cc
@@ -3518,43 +3518,36 @@  dt_operand::gen_phi_on_cond (FILE *f, int indent, int depth)
 {
   fprintf_indent (f, indent,
     "basic_block _b%d = gimple_bb (_a%d);\n", depth, depth);
+  fprintf_indent (f, indent, "basic_block _b_cond_%d;\n", depth);
 
-  fprintf_indent (f, indent, "if (gimple_phi_num_args (_a%d) == 2)\n", depth);
+  fprintf_indent (f, indent, "if (gimple_phi_num_args (_a%d) == 2\n", depth);
 
-  indent += 2;
-  fprintf_indent (f, indent, "{\n");
   indent += 2;
 
   fprintf_indent (f, indent,
-    "basic_block _pb_0_%d = EDGE_PRED (_b%d, 0)->src;\n", depth, depth);
-  fprintf_indent (f, indent,
-    "basic_block _pb_1_%d = EDGE_PRED (_b%d, 1)->src;\n", depth, depth);
-  fprintf_indent (f, indent,
-    "basic_block _db_%d = safe_dyn_cast <gcond *> (*gsi_last_bb (_pb_0_%d)) ? "
-    "_pb_0_%d : _pb_1_%d;\n", depth, depth, depth, depth);
+    "  && (control_flow_graph_case_0_match (_b%d, &_b_cond_%d)\n",
+    depth, depth);
   fprintf_indent (f, indent,
-    "basic_block _other_db_%d = safe_dyn_cast <gcond *> "
-    "(*gsi_last_bb (_pb_0_%d)) ? _pb_1_%d : _pb_0_%d;\n",
-    depth, depth, depth, depth);
+    "      || control_flow_graph_case_1_match (_b%d, &_b_cond_%d)))\n",
+    depth, depth);
+
+  indent += 2;
+  fprintf_indent (f, indent, "{\n");
+  indent += 2;
 
   fprintf_indent (f, indent,
-    "gcond *_ct_%d = safe_dyn_cast <gcond *> (*gsi_last_bb (_db_%d));\n",
+    "gcond *_cond_%d = safe_dyn_cast <gcond *> (*gsi_last_bb (_b_cond_%d));\n",
     depth, depth);
-  fprintf_indent (f, indent, "if (_ct_%d"
-    " && EDGE_COUNT (_other_db_%d->preds) == 1\n", depth, depth);
-  fprintf_indent (f, indent,
-    "  && EDGE_COUNT (_other_db_%d->succs) == 1\n", depth);
-  fprintf_indent (f, indent,
-    "  && EDGE_PRED (_other_db_%d, 0)->src == _db_%d)\n", depth, depth);
+  fprintf_indent (f, indent, "if (_cond_%d)\n", depth);
 
   indent += 2;
   fprintf_indent (f, indent, "{\n");
   indent += 2;
 
   fprintf_indent (f, indent,
-    "tree _cond_lhs_%d = gimple_cond_lhs (_ct_%d);\n", depth, depth);
+    "tree _cond_lhs_%d = gimple_cond_lhs (_cond_%d);\n", depth, depth);
   fprintf_indent (f, indent,
-    "tree _cond_rhs_%d = gimple_cond_rhs (_ct_%d);\n", depth, depth);
+    "tree _cond_rhs_%d = gimple_cond_rhs (_cond_%d);\n", depth, depth);
 
   char opname_0[20];
   char opname_1[20];
@@ -3562,7 +3555,7 @@  dt_operand::gen_phi_on_cond (FILE *f, int indent, int depth)
   gen_opname (opname_0, 0);
 
   fprintf_indent (f, indent,
-    "tree %s = build2 (gimple_cond_code (_ct_%d), "
+    "tree %s = build2 (gimple_cond_code (_cond_%d), "
     "boolean_type_node, _cond_lhs_%d, _cond_rhs_%d);\n",
     opname_0, depth, depth, depth);
 
diff --git a/gcc/gimple-match-head.cc b/gcc/gimple-match-head.cc
index 924d3f1e710..eb43e5c58cb 100644
--- a/gcc/gimple-match-head.cc
+++ b/gcc/gimple-match-head.cc
@@ -375,3 +375,118 @@  gimple_bitwise_inverted_equal_p (tree expr1, tree expr2, bool &wascmp, tree (*va
     return true;
   return false;
 }
+
+/*
+ * Return TRUE if the cfg matches the below layout by the given b2 in
+ * the first argument.  Or return FALSE.
+ *
+ * If return TRUE, the output argument b_out will be updated to the b0
+ * block as below example.
+ *
+ * If return FALSE, the output argument b_out will be NULL_BLOCK.
+ *
+ *    |
+ *    |
+ *    v
+ * +------+
+ * | b0:  |
+ * | def  |       +-----+
+ * | ...  |       | b1: |
+ * | cond |------>| def |
+ * +------+       | ... |
+ *    |           +-----+
+ *    |              |
+ *    v              |
+ * +-----+           |
+ * | b2: |           |
+ * | def |<----------+
+ * +-----+
+ */
+static inline bool
+control_flow_graph_case_0_match (basic_block b2, basic_block *b_out)
+{
+  *b_out = NULL;
+
+  if (EDGE_COUNT (b2->preds) != 2)
+    return false;
+
+  basic_block pred_0 = EDGE_PRED (b2, 0)->src;
+  basic_block pred_1 = EDGE_PRED (b2, 1)->src;
+
+  if (pred_0 == NULL || pred_1 == NULL)
+    return false;
+
+  if (!(EDGE_COUNT (pred_0->succs) == 2 && EDGE_COUNT (pred_1->succs) == 1)
+     && !(EDGE_COUNT (pred_0->succs) == 1 && EDGE_COUNT (pred_1->succs) == 2))
+    return false;
+
+  basic_block b0 = EDGE_COUNT (pred_0->succs) == 2 ? pred_0 : pred_1;
+  basic_block b1 = EDGE_COUNT (pred_0->succs) == 1 ? pred_0 : pred_1;
+
+  if (EDGE_COUNT (b1->preds) != 1 || EDGE_PRED (b1, 0)->src != b0)
+    return false;
+
+  *b_out = b0;
+  return true;
+}
+
+/*
+ * Return TRUE if the cfg matches the below layout by the given b3 in
+ * the first argument.  Or return FALSE.
+ *
+ * If return TRUE, the output argument b_out will be updated to the b0
+ * block as below example.
+ *
+ * If return FALSE, the output argument b_out will be NULL.
+ *
+ *    |
+ *    |
+ *    v
+ * +------+
+ * | b0:  |
+ * | ...  |       +-----+
+ * | cond |------>| b2: |
+ * +------+       | ... |
+ *    |           +-----+
+ *    |              |
+ *    v              |
+ * +-----+           |
+ * | b1: |           |
+ * | ... |           |
+ * +-----+           |
+ *    |              |
+ *    |              |
+ *    v              |
+ * +-----+           |
+ * | b3: |<----------+
+ * | ... |
+ * +-----+
+ */
+static inline bool
+control_flow_graph_case_1_match (basic_block b3, basic_block *b_out)
+{
+  *b_out = NULL;
+
+  if (EDGE_COUNT (b3->preds) != 2)
+    return false;
+
+  basic_block b1 = EDGE_PRED (b3, 0)->src;
+  basic_block b2 = EDGE_PRED (b3, 1)->src;
+
+  if (b1 == NULL || b2 == NULL)
+    return false;
+
+  if (EDGE_COUNT (b1->succs) != 1
+      || EDGE_COUNT (b1->preds) != 1
+      || EDGE_COUNT (b2->succs) != 1
+      || EDGE_COUNT (b2->preds) != 1)
+    return false;
+
+  basic_block b0 = EDGE_PRED (b1, 0)->src;
+
+  if (EDGE_COUNT (b0->succs) != 2 || EDGE_PRED (b2, 0)->src != b0)
+    return false;
+
+  *b_out = b0;
+  return true;
+}