Hi,
with all-SLP we sometimes annotate statements slightly differently. This patch
uses STMT_VINFO_RELEVANT_P in order to walk through potential program points
when doing dynamic LMUL costing.
Also it makes the LMUL estimate always use the same path. This helps fix a
number of test cases that regressed since GCC 14.
There are still some failing tests but in the majority of cases it appears to
me that the chosen LMUL is still correct and we just expect different log
messages. I think there are also a few tests that now fail differently than
before.
Regtested on rv64gcv_zvl512b. Want to see what the CI returns, it definitely
won't be "clean". I'm not 100% sure if we want that patch in the current stage
but it does fix some regressions and seems reasonably safe.
Regards
Robin
gcc/ChangeLog:
* config/riscv/riscv-vector-costs.cc (compute_estimated_lmul):
Always use vect_vf_for_cost and TARGET_MIN_VLEN.
gcc/testsuite/ChangeLog:
* gcc.dg/vect/costmodel/riscv/rvv/dynamic-lmul4-3.c: Adjust
expectations.
* gcc.dg/vect/costmodel/riscv/rvv/dynamic-lmul8-9.c: Ditto.
---
gcc/config/riscv/riscv-vector-costs.cc | 25 ++-----------------
.../costmodel/riscv/rvv/dynamic-lmul4-3.c | 2 +-
.../costmodel/riscv/rvv/dynamic-lmul8-9.c | 1 -
3 files changed, 3 insertions(+), 25 deletions(-)
diff --git a/gcc/config/riscv/riscv-vector-costs.cc
b/gcc/config/riscv/riscv-vector-costs.cc
index d4571b65e19..5149751ae76 100644
--- a/gcc/config/riscv/riscv-vector-costs.cc
+++ b/gcc/config/riscv/riscv-vector-costs.cc
@@ -205,9 +205,7 @@ compute_local_program_points (
if (!is_gimple_assign_or_call (gsi_stmt (si)))
continue;
stmt_vec_info stmt_info = vinfo->lookup_stmt (gsi_stmt (si));
- enum stmt_vec_info_type type
- = STMT_VINFO_TYPE (vect_stmt_to_vectorize (stmt_info));
- if (type != undef_vec_info_type)
+ if (STMT_VINFO_RELEVANT_P (stmt_info))
{
stmt_point info = {point, gsi_stmt (si), stmt_info};
program_points.safe_push (info);
@@ -597,7 +595,7 @@ compute_estimated_lmul (loop_vec_info loop_vinfo,
machine_mode mode)
int regno_alignment = riscv_get_v_regno_alignment (loop_vinfo->vector_mode);
if (riscv_v_ext_vls_mode_p (loop_vinfo->vector_mode))
return regno_alignment;
- else if (known_eq (LOOP_VINFO_SLP_UNROLLING_FACTOR (loop_vinfo), 1U))
+ else
{
int estimated_vf = vect_vf_for_cost (loop_vinfo);
int estimated_lmul = estimated_vf * GET_MODE_BITSIZE (mode).to_constant
()
@@ -607,25 +605,6 @@ compute_estimated_lmul (loop_vec_info loop_vinfo,
machine_mode mode)
else
return estimated_lmul;
}
- else
- {
- /* Estimate the VLA SLP LMUL. */
- if (regno_alignment > RVV_M1)
- return regno_alignment;
- else if (mode != QImode
- || LOOP_VINFO_SLP_UNROLLING_FACTOR (loop_vinfo).is_constant ())
- {
- int ratio;
- if (can_div_trunc_p (BYTES_PER_RISCV_VECTOR,
- GET_MODE_SIZE (loop_vinfo->vector_mode), &ratio))
- {
- if (ratio == 1)
- return RVV_M4;
- else if (ratio == 2)
- return RVV_M2;
- }
- }
- }
return 0;
}
diff --git a/gcc/testsuite/gcc.dg/vect/costmodel/riscv/rvv/dynamic-lmul4-3.c
b/gcc/testsuite/gcc.dg/vect/costmodel/riscv/rvv/dynamic-lmul4-3.c
index 85e3021f1c2..b5a7f180228 100644
--- a/gcc/testsuite/gcc.dg/vect/costmodel/riscv/rvv/dynamic-lmul4-3.c
+++ b/gcc/testsuite/gcc.dg/vect/costmodel/riscv/rvv/dynamic-lmul4-3.c
@@ -45,4 +45,4 @@ void foo2 (int64_t *__restrict a,
/* { dg-final { scan-tree-dump-not "Preferring smaller LMUL loop because it
has unexpected spills" "vect" } } */
/* { dg-final { scan-tree-dump-times "Maximum lmul = 8" 1 "vect" } } */
/* { dg-final { scan-tree-dump-times "Maximum lmul = 4" 1 "vect" } } */
-/* { dg-final { scan-tree-dump-times "Maximum lmul = 2" 1 "vect" } } */
+/* { dg-final { scan-tree-dump-times "Maximum lmul = 2" 3 "vect" } } */
diff --git a/gcc/testsuite/gcc.dg/vect/costmodel/riscv/rvv/dynamic-lmul8-9.c
b/gcc/testsuite/gcc.dg/vect/costmodel/riscv/rvv/dynamic-lmul8-9.c
index 793d16418bf..56234580fa8 100644
--- a/gcc/testsuite/gcc.dg/vect/costmodel/riscv/rvv/dynamic-lmul8-9.c
+++ b/gcc/testsuite/gcc.dg/vect/costmodel/riscv/rvv/dynamic-lmul8-9.c
@@ -14,6 +14,5 @@ foo (int64_t *__restrict a, int64_t init, int n)
/* { dg-final { scan-assembler {e64,m8} } } */
/* { dg-final { scan-assembler-not {csrr} } } */
/* { dg-final { scan-tree-dump-not "Preferring smaller LMUL loop because it
has unexpected spills" "vect" } } */
-/* { dg-final { scan-tree-dump-times "Maximum lmul = 8" 1 "vect" } } */
/* { dg-final { scan-tree-dump-times "Maximum lmul = 4" 1 "vect" } } */
/* { dg-final { scan-tree-dump-times "Maximum lmul = 2" 1 "vect" } } */
--
2.48.1
