https://gcc.gnu.org/g:963d5362c598d48ee7a896e674d2a68c41179785
commit r16-2120-g963d5362c598d48ee7a896e674d2a68c41179785
Author: Tamar Christina <tamar.christ...@arm.com>
Date: Wed Jul 9 08:42:02 2025 +0100
middle-end: Use rounding division for ranges for partial vectors [PR120922]
This patch adds support for niters ranges for partial
vector loops.
Due to the last iteration being partial the bounds should
be at least 1 but niters // vf as the max.
gcc/ChangeLog:
PR tree-optimization/120922
* tree-vect-loop-manip.cc (vect_gen_vector_loop_niters): Support
range
for partial vectors.
Diff:
---
gcc/tree-vect-loop-manip.cc | 18 ++++++++++++++----
1 file changed, 14 insertions(+), 4 deletions(-)
diff --git a/gcc/tree-vect-loop-manip.cc b/gcc/tree-vect-loop-manip.cc
index 9c58a6a01d7c..2d01a4b0ed1c 100644
--- a/gcc/tree-vect-loop-manip.cc
+++ b/gcc/tree-vect-loop-manip.cc
@@ -2857,11 +2857,21 @@ vect_gen_vector_loop_niters (loop_vec_info loop_vinfo,
tree niters,
we set range information to make niters analyzer's life easier.
Note the number of latch iteration value can be TYPE_MAX_VALUE so
we have to represent the vector niter TYPE_MAX_VALUE + 1 / vf. */
- if (stmts != NULL
- && const_vf > 0
- && !LOOP_VINFO_USING_PARTIAL_VECTORS_P (loop_vinfo))
+ if (stmts != NULL && const_vf > 0)
{
- if (niters_no_overflow)
+ if (niters_no_overflow
+ && LOOP_VINFO_USING_PARTIAL_VECTORS_P (loop_vinfo))
+ {
+ int_range<1> vr (type,
+ wi::one (TYPE_PRECISION (type)),
+ wi::div_ceil (wi::max_value
+ (TYPE_PRECISION (type),
+ TYPE_SIGN (type)),
+ const_vf,
+ TYPE_SIGN (type)));
+ set_range_info (niters_vector, vr);
+ }
+ else if (niters_no_overflow)
{
int_range<1> vr (type,
wi::one (TYPE_PRECISION (type)),
