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| author | Sudakshina Das <sudi.das@arm.com> | 2019-12-09 10:22:01 +0000 |
|---|---|---|
| committer | Sudakshina Das <sudi@gcc.gnu.org> | 2019-12-09 10:22:01 +0000 |
| commit | e3126e5f649c8eebe07fc517d86f10d6867b7eec (patch) | |
| tree | 666f91365cb8eb2177a3b7b04ea599caacd740ca /gcc | |
| parent | 49647b7b25673273262fb630598027c6d841690f (diff) | |
| download | gcc-e3126e5f649c8eebe07fc517d86f10d6867b7eec.zip gcc-e3126e5f649c8eebe07fc517d86f10d6867b7eec.tar.gz gcc-e3126e5f649c8eebe07fc517d86f10d6867b7eec.tar.bz2 | |
[GCC, Vect] Fix costing for vector shifts
While looking at the vectorization for following example, we realized that
even though vectorizable_shift function was distinguishing vector shifted
by vector from vector shifted by scalar, while modelling the cost it would
always add the cost of building a vector constant despite not needing it for
vector shifted by scalar.
This patch fixes this by using scalar_shift_arg to determine whether we need
to build a vector for the second operand or not. This causes the test case
below to now vectorize.
gcc/ChangeLog:
2019-12-09 Sudakshina Das <sudi.das@arm.com>
Richard Sandiford <richard.sandiford@arm.com>
* tree-vect-stmt.c (vectorizable_shift): Condition ndts for
vect_model_simple_cost call on scalar_shift_arg.
gcc/testsuite/ChangeLog:
2019-12-09 Sudakshina Das <sudi.das@arm.com>
* gcc.dg/vect/vect-shift-5.c: New test.
Co-Authored-By: Richard Sandiford <richard.sandiford@arm.com>
From-SVN: r279114
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 6 | ||||
| -rw-r--r-- | gcc/testsuite/ChangeLog | 4 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.dg/vect/vect-shift-5.c | 19 | ||||
| -rw-r--r-- | gcc/tree-vect-stmts.c | 3 |
4 files changed, 31 insertions, 1 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 1c953d2..3d98bef 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2019-12-09 Sudakshina Das <sudi.das@arm.com> + Richard Sandiford <richard.sandiford@arm.com> + + * tree-vect-stmt.c (vectorizable_shift): Condition ndts for + vect_model_simple_cost call on scalar_shift_arg. + 2019-12-09 Jakub Jelinek <jakub@redhat.com> PR tree-optimization/92834 diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 53bbc12..272a83e 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,7 @@ +2019-12-09 Sudakshina Das <sudi.das@arm.com> + + * gcc.dg/vect/vect-shift-5.c: New test. + 2019-12-09 Jakub Jelinek <jakub@redhat.com> PR tree-optimization/92834 diff --git a/gcc/testsuite/gcc.dg/vect/vect-shift-5.c b/gcc/testsuite/gcc.dg/vect/vect-shift-5.c new file mode 100644 index 0000000..c1fd4f2 --- /dev/null +++ b/gcc/testsuite/gcc.dg/vect/vect-shift-5.c @@ -0,0 +1,19 @@ +/* { dg-do compile } */ +/* { dg-require-effective-target vect_shift } */ +/* { dg-require-effective-target vect_int } */ + +typedef unsigned int uint32_t; +typedef short unsigned int uint16_t; + +int foo (uint32_t arr[4][4]) +{ + int sum = 0; + for(int i = 0; i < 4; i++) + { + sum += ((arr[0][i] >> 10) * 20) + ((arr[1][i] >> 11) & 53) + + ((arr[2][i] >> 12) * 7) + ((arr[3][i] >> 13) ^ 43); + } + return (((uint16_t)sum) + ((uint32_t)sum >> 16)) >> 1; +} + +/* { dg-final { scan-tree-dump {vectorizable_shift ===[\n\r][^\n]*prologue_cost = 0} "vect" } } */ diff --git a/gcc/tree-vect-stmts.c b/gcc/tree-vect-stmts.c index 2cb6b15..396ff15 100644 --- a/gcc/tree-vect-stmts.c +++ b/gcc/tree-vect-stmts.c @@ -5764,7 +5764,8 @@ vectorizable_shift (stmt_vec_info stmt_info, gimple_stmt_iterator *gsi, { STMT_VINFO_TYPE (stmt_info) = shift_vec_info_type; DUMP_VECT_SCOPE ("vectorizable_shift"); - vect_model_simple_cost (stmt_info, ncopies, dt, ndts, slp_node, cost_vec); + vect_model_simple_cost (stmt_info, ncopies, dt, + scalar_shift_arg ? 1 : ndts, slp_node, cost_vec); return true; } |