From: Pan Li <[email protected]>
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 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 for
a new control flow when gen phi on condition.
Signed-off-by: Pan Li <[email protected]>
---
gcc/genmatch.cc | 85 +++++++++++++++++++++++++++++++++++++++++++------
1 file changed, 76 insertions(+), 9 deletions(-)
diff --git a/gcc/genmatch.cc b/gcc/genmatch.cc
index a56bd90cb2c..f538df1be62 100644
--- a/gcc/genmatch.cc
+++ b/gcc/genmatch.cc
@@ -3529,28 +3529,95 @@ dt_operand::gen_phi_on_cond (FILE *f, int indent, int
depth)
"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);
+ "gcond *_ct_0_%d = safe_dyn_cast <gcond *> (*gsi_last_bb (_pb_0_%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",
+ "gcond *_ct_1_%d = safe_dyn_cast <gcond *> (*gsi_last_bb (_pb_1_%d));\n",
+ depth, depth);
+ fprintf_indent (f, indent,
+ "gcond *_ct_a_%d = _ct_0_%d ? _ct_0_%d : _ct_1_%d;\n",
+ depth, depth, depth, depth);
+ fprintf_indent (f, indent,
+ "basic_block _db_%d = _ct_0_%d ? _pb_0_%d : _pb_1_%d;\n",
+ depth, depth, depth, depth);
+ fprintf_indent (f, indent,
+ "basic_block _other_db_%d = _ct_0_%d ? _pb_1_%d : _pb_0_%d;\n",
depth, depth, depth, depth);
fprintf_indent (f, indent,
- "gcond *_ct_%d = safe_dyn_cast <gcond *> (*gsi_last_bb (_db_%d));\n",
- depth, depth);
- fprintf_indent (f, indent, "if (_ct_%d"
+ "edge _e_00_%d = _pb_0_%d->preds ? EDGE_PRED (_pb_0_%d, 0) : NULL;\n",
+ depth, depth, depth);
+ fprintf_indent (f, indent,
+ "basic_block _pb_00_%d = _e_00_%d ? _e_00_%d->src : NULL;\n",
+ depth, depth, depth);
+ fprintf_indent (f, indent,
+ "gcond *_ct_b_%d = _pb_00_%d ? "
+ "safe_dyn_cast <gcond *> (*gsi_last_bb (_pb_00_%d)) : NULL;\n",
+ depth, depth, depth);
+
+ /* Case 1 flow for PHI.
+ * +------+
+ * | def |
+ * | ... | +-----+
+ * | cond |------>| def |
+ * +------+ | ... |
+ * | +-----+
+ * | |
+ * v |
+ * +-----+ |
+ * | PHI |<----------+
+ * +-----+
+ */
+ fprintf_indent (f, indent, "if ((_ct_a_%d"
" && EDGE_COUNT (_other_db_%d->preds) == 1\n", depth, depth);
fprintf_indent (f, indent,
- " && EDGE_COUNT (_other_db_%d->succs) == 1\n", depth);
+ " && 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, " ||\n");
+
+ /* Case 2 flow for PHI.
+ * +------+
+ * | def |
+ * | ... | +-----+
+ * | cond |------>| def |
+ * +------+ | ... |
+ * | +-----+
+ * | |
+ * v |
+ * +-----+ |
+ * | def | |
+ * | ... | |
+ * +-----+ |
+ * | |
+ * | |
+ * v |
+ * +-----+ |
+ * | PHI |<----------+
+ * +-----+
+ */
+ fprintf_indent (f, indent,
+ " (_ct_b_%d && _pb_00_%d && EDGE_COUNT (_pb_0_%d->succs) == 1\n",
+ depth, depth, depth);
+ fprintf_indent (f, indent,
+ " && EDGE_COUNT (_pb_0_%d->preds) == 1\n", depth);
fprintf_indent (f, indent,
- " && EDGE_PRED (_other_db_%d, 0)->src == _db_%d)\n", depth, depth);
+ " && EDGE_COUNT (_other_db_%d->preds) == 1\n", 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 == _pb_00_%d))\n", depth, depth);
indent += 2;
fprintf_indent (f, indent, "{\n");
indent += 2;
+ fprintf_indent (f, indent,
+ "gcond *_ct_%d = _ct_a_%d ? _ct_a_%d : _ct_b_%d;\n",
+ depth, depth, depth, depth);
fprintf_indent (f, indent,
"tree _cond_lhs_%d = gimple_cond_lhs (_ct_%d);\n", depth, depth);
fprintf_indent (f, indent,
--
2.43.0
