Hi, Han.
It's awesome that some one want to optimize dynamic LMUL feature of GCC.
I knew this feature is not stable yet and I failed to find the time to optimize
it (Still busy with fixing bugs).
Could you give me more details why this patch can refine those 2 cases with
picking larger LMUL (I am happy with those 2 cases be changed as using larger
LMUL )?
It seems this patch is ignoring the first vectorized statement during the live
calculation ?
Thanks.
juzhe.zh...@rivai.ai
From: demin.han
Date: 2023-12-20 16:15
To: gcc-patches@gcc.gnu.org
CC: juzhe.zh...@rivai.ai; pan2...@intel.com
Subject: [PATCH] RISC-V: Fix calculation of max live vregs
For the stmt _1 = _2 + _3, assume that _2 or _3 not used after this stmt.
_1 can use same register with _2 or _3 if without early clobber.
Two registers are needed, but current calculation is three.
This patch preserves point 0 for bb entry and excludes its def when
calculates live regs of certain point.
Signed-off-by: demin.han <demin....@starfivetech.com>
gcc/ChangeLog:
* config/riscv/riscv-vector-costs.cc (max_number_of_live_regs): Fix
max live vregs calc
(preferred_new_lmul_p): Ditto
gcc/testsuite/ChangeLog:
* gcc.dg/vect/costmodel/riscv/rvv/dynamic-lmul2-7.c: Moved to...
* gcc.dg/vect/costmodel/riscv/rvv/dynamic-lmul4-10.c: ...here.
* gcc.dg/vect/costmodel/riscv/rvv/dynamic-lmul4-4.c: Moved to...
* gcc.dg/vect/costmodel/riscv/rvv/dynamic-lmul8-11.c: ...here.
---
gcc/config/riscv/riscv-vector-costs.cc | 10 +++++-----
.../rvv/{dynamic-lmul2-7.c => dynamic-lmul4-10.c} | 6 +++---
.../rvv/{dynamic-lmul4-4.c => dynamic-lmul8-11.c} | 6 +++---
3 files changed, 11 insertions(+), 11 deletions(-)
rename gcc/testsuite/gcc.dg/vect/costmodel/riscv/rvv/{dynamic-lmul2-7.c =>
dynamic-lmul4-10.c} (79%)
rename gcc/testsuite/gcc.dg/vect/costmodel/riscv/rvv/{dynamic-lmul4-4.c =>
dynamic-lmul8-11.c} (87%)
diff --git a/gcc/config/riscv/riscv-vector-costs.cc
b/gcc/config/riscv/riscv-vector-costs.cc
index e7bc9ed5233..a316603e207 100644
--- a/gcc/config/riscv/riscv-vector-costs.cc
+++ b/gcc/config/riscv/riscv-vector-costs.cc
@@ -123,7 +123,7 @@ compute_local_program_points (
/* Collect the stmts that is vectorized and mark their program point. */
for (i = 0; i < nbbs; i++)
{
- int point = 0;
+ int point = 1;
basic_block bb = bbs[i];
vec<stmt_point> program_points = vNULL;
if (dump_enabled_p ())
@@ -300,13 +300,13 @@ max_number_of_live_regs (const basic_block bb,
unsigned int i;
unsigned int live_point = 0;
auto_vec<unsigned int> live_vars_vec;
- live_vars_vec.safe_grow_cleared (max_point + 1, true);
+ live_vars_vec.safe_grow_cleared (max_point, true);
for (hash_map<tree, pair>::iterator iter = live_ranges.begin ();
iter != live_ranges.end (); ++iter)
{
tree var = (*iter).first;
pair live_range = (*iter).second;
- for (i = live_range.first; i <= live_range.second; i++)
+ for (i = live_range.first + 1; i <= live_range.second; i++)
{
machine_mode mode = TYPE_MODE (TREE_TYPE (var));
unsigned int nregs
@@ -485,7 +485,7 @@ update_local_live_ranges (
if (!program_points_per_bb.get (e->src))
continue;
unsigned int max_point
- = (*program_points_per_bb.get (e->src)).length () - 1;
+ = (*program_points_per_bb.get (e->src)).length ();
live_range = live_ranges->get (def);
if (!live_range)
continue;
@@ -571,7 +571,7 @@ preferred_new_lmul_p (loop_vec_info other_loop_vinfo)
{
basic_block bb = (*iter).first;
unsigned int max_point
- = (*program_points_per_bb.get (bb)).length () - 1;
+ = (*program_points_per_bb.get (bb)).length () + 1;
if ((*iter).second.is_empty ())
continue;
/* We prefer larger LMUL unless it causes register spillings. */
diff --git a/gcc/testsuite/gcc.dg/vect/costmodel/riscv/rvv/dynamic-lmul2-7.c
b/gcc/testsuite/gcc.dg/vect/costmodel/riscv/rvv/dynamic-lmul4-10.c
similarity index 79%
rename from gcc/testsuite/gcc.dg/vect/costmodel/riscv/rvv/dynamic-lmul2-7.c
rename to gcc/testsuite/gcc.dg/vect/costmodel/riscv/rvv/dynamic-lmul4-10.c
index 636332dbb62..74e629168f8 100644
--- a/gcc/testsuite/gcc.dg/vect/costmodel/riscv/rvv/dynamic-lmul2-7.c
+++ b/gcc/testsuite/gcc.dg/vect/costmodel/riscv/rvv/dynamic-lmul4-10.c
@@ -17,10 +17,10 @@ bar (int *x, int a, int b, int n)
return sum1 + sum2;
}
-/* { dg-final { scan-assembler {e32,m2} } } */
+/* { dg-final { scan-assembler {e32,m4} } } */
/* { dg-final { scan-assembler-not {jr} } } */
/* { dg-final { scan-assembler-times {ret} 2 } } *
/* { 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 "Maximum lmul = 2" "vect" } } */
+/* { dg-final { scan-tree-dump "Maximum lmul = 4" "vect" } } */
+/* { dg-final { scan-tree-dump-not "Maximum lmul = 2" "vect" } } */
/* { dg-final { scan-tree-dump-not "Maximum lmul = 1" "vect" } } */
diff --git a/gcc/testsuite/gcc.dg/vect/costmodel/riscv/rvv/dynamic-lmul4-4.c
b/gcc/testsuite/gcc.dg/vect/costmodel/riscv/rvv/dynamic-lmul8-11.c
similarity index 87%
rename from gcc/testsuite/gcc.dg/vect/costmodel/riscv/rvv/dynamic-lmul4-4.c
rename to gcc/testsuite/gcc.dg/vect/costmodel/riscv/rvv/dynamic-lmul8-11.c
index 01a359bc7c8..01c976dd67b 100644
--- a/gcc/testsuite/gcc.dg/vect/costmodel/riscv/rvv/dynamic-lmul4-4.c
+++ b/gcc/testsuite/gcc.dg/vect/costmodel/riscv/rvv/dynamic-lmul8-11.c
@@ -39,9 +39,9 @@ void foo2 (int64_t *__restrict a,
}
}
-/* { dg-final { scan-assembler {e64,m4} } } */
+/* { dg-final { scan-assembler {e64,m8} } } */
/* { dg-final { scan-assembler-not {csrr} } } */
-/* { dg-final { scan-tree-dump-times "Maximum lmul = 8" 1 "vect" } } */
-/* { dg-final { scan-tree-dump "Maximum lmul = 4" "vect" } } */
+/* { dg-final { scan-tree-dump "Maximum lmul = 8" "vect" } } */
+/* { dg-final { scan-tree-dump-not "Maximum lmul = 4" "vect" } } */
/* { dg-final { scan-tree-dump-not "Maximum lmul = 2" "vect" } } */
/* { dg-final { scan-tree-dump-not "Maximum lmul = 1" "vect" } } */
--
2.43.0
