From d3867483044ae00bac6daaeac6274e95254fb991 Mon Sep 17 00:00:00 2001
From: Richard Sandiford <richard.sandiford@linaro.org>
Date: Tue, 2 Jan 2018 18:27:24 +0000
Subject: [PATCH] Use vec_perm_builder::series_p in shift_amt_for_vec_perm_mask
This patch makes shift_amt_for_vec_perm_mask use series_p to check
for the simple case of a natural linear series before falling back
to testing each element individually. The series_p test works with
variable-length vectors but testing every individual element doesn't.
2018-01-02 Richard Sandiford <richard.sandiford@linaro.org>
gcc/
* optabs.c (shift_amt_for_vec_perm_mask): Try using series_p
before testing each element individually.
* tree-vect-generic.c (lower_vec_perm): Likewise.
From-SVN: r256099
---
gcc/ChangeLog | 6 ++++++
gcc/optabs.c | 22 +++++++++++-----------
gcc/tree-vect-generic.c | 19 ++++++++++++-------
3 files changed, 29 insertions(+), 18 deletions(-)
diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 9e3face038b3..1dfb6839d10b 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2018-01-02 Richard Sandiford <richard.sandiford@linaro.org>
+
+ * optabs.c (shift_amt_for_vec_perm_mask): Try using series_p
+ before testing each element individually.
+ * tree-vect-generic.c (lower_vec_perm): Likewise.
+
2018-01-02 Richard Sandiford <richard.sandiford@linaro.org>
* selftest.h (selftest::vec_perm_indices_c_tests): Declare.
diff --git a/gcc/optabs.c b/gcc/optabs.c
index e9ce42fb9eef..dcd94cd5a301 100644
--- a/gcc/optabs.c
+++ b/gcc/optabs.c
@@ -5395,20 +5395,20 @@ vector_compare_rtx (machine_mode cmp_mode, enum tree_code tcode,
static rtx
shift_amt_for_vec_perm_mask (machine_mode mode, const vec_perm_indices &sel)
{
- unsigned int i, first, nelt = GET_MODE_NUNITS (mode);
+ unsigned int nelt = GET_MODE_NUNITS (mode);
unsigned int bitsize = GET_MODE_UNIT_BITSIZE (mode);
-
- first = sel[0];
+ unsigned int first = sel[0];
if (first >= nelt)
return NULL_RTX;
- for (i = 1; i < nelt; i++)
- {
- int idx = sel[i];
- unsigned int expected = i + first;
- /* Indices into the second vector are all equivalent. */
- if (idx < 0 || (MIN (nelt, (unsigned) idx) != MIN (nelt, expected)))
- return NULL_RTX;
- }
+
+ if (!sel.series_p (0, 1, first, 1))
+ for (unsigned int i = 1; i < nelt; i++)
+ {
+ unsigned int expected = i + first;
+ /* Indices into the second vector are all equivalent. */
+ if (MIN (nelt, sel[i]) != MIN (nelt, expected))
+ return NULL_RTX;
+ }
return gen_int_shift_amount (mode, first * bitsize);
}
diff --git a/gcc/tree-vect-generic.c b/gcc/tree-vect-generic.c
index 767721cd62ca..602cea377554 100644
--- a/gcc/tree-vect-generic.c
+++ b/gcc/tree-vect-generic.c
@@ -1320,15 +1320,20 @@ lower_vec_perm (gimple_stmt_iterator *gsi)
&& indices[0]
&& indices[0] < elements)
{
- for (i = 1; i < elements; ++i)
+ bool ok_p = indices.series_p (0, 1, indices[0], 1);
+ if (!ok_p)
{
- unsigned int expected = i + indices[0];
- /* Indices into the second vector are all equivalent. */
- if (MIN (elements, (unsigned) indices[i])
- != MIN (elements, expected))
- break;
+ for (i = 1; i < elements; ++i)
+ {
+ unsigned int expected = i + indices[0];
+ /* Indices into the second vector are all equivalent. */
+ if (MIN (elements, (unsigned) indices[i])
+ != MIN (elements, expected))
+ break;
+ }
+ ok_p = i == elements;
}
- if (i == elements)
+ if (ok_p)
{
gimple_assign_set_rhs3 (stmt, mask);
update_stmt (stmt);
--
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