[Committed] RISC-V: Tweak generic vector COST model

[Juzhe-Zhong]

Notice current generic vector cost model make PR112387 failed to vectorize.

Adapt it same as ARM SVE generic vector cost model which can fix it.

Committed as it is obvious fix.

        PR target/112387

gcc/ChangeLog:

        * config/riscv/riscv.cc: Adapt generic cost model same ARM SVE.

gcc/testsuite/ChangeLog:

        * gcc.dg/vect/costmodel/riscv/rvv/pr112387.c: Moved to...
        * gcc.dg/vect/costmodel/riscv/rvv/pr112387-1.c: ...here.
        * gcc.dg/vect/costmodel/riscv/rvv/pr112387-2.c: New test.

---
 gcc/config/riscv/riscv.cc                     | 24 +++++++++----------
 .../riscv/rvv/{pr112387.c => pr112387-1.c}    |  0
 .../vect/costmodel/riscv/rvv/pr112387-2.c     | 19 +++++++++++++++
 3 files changed, 31 insertions(+), 12 deletions(-)
 rename gcc/testsuite/gcc.dg/vect/costmodel/riscv/rvv/{pr112387.c => 
pr112387-1.c} (100%)
 create mode 100644 gcc/testsuite/gcc.dg/vect/costmodel/riscv/rvv/pr112387-2.c

diff --git a/gcc/config/riscv/riscv.cc b/gcc/config/riscv/riscv.cc
index 2dc44244309..481ad77dd49 100644
--- a/gcc/config/riscv/riscv.cc
+++ b/gcc/config/riscv/riscv.cc
@@ -355,13 +355,13 @@ static const common_vector_cost generic_vls_vector_cost = 
{
   1, /* fp_stmt_cost  */
   1, /* gather_load_cost  */
   1, /* scatter_store_cost  */
-  1, /* vec_to_scalar_cost  */
+  2, /* vec_to_scalar_cost  */
   1, /* scalar_to_vec_cost  */
-  1, /* permute_cost  */
-  3, /* align_load_cost  */
-  3, /* align_store_cost  */
-  3, /* unalign_load_cost  */
-  3, /* unalign_store_cost  */
+  2, /* permute_cost  */
+  1, /* align_load_cost  */
+  1, /* align_store_cost  */
+  1, /* unalign_load_cost  */
+  1, /* unalign_store_cost  */
 };
 
 /* Generic costs for VLA vector operations.  */
@@ -371,13 +371,13 @@ static const scalable_vector_cost generic_vla_vector_cost 
= {
     1, /* fp_stmt_cost  */
     1, /* gather_load_cost  */
     1, /* scatter_store_cost  */
-    1, /* vec_to_scalar_cost  */
+    2, /* vec_to_scalar_cost  */
     1, /* scalar_to_vec_cost  */
-    1, /* permute_cost  */
-    3, /* align_load_cost  */
-    3, /* align_store_cost  */
-    3, /* unalign_load_cost  */
-    3, /* unalign_store_cost  */
+    2, /* permute_cost  */
+    1, /* align_load_cost  */
+    1, /* align_store_cost  */
+    1, /* unalign_load_cost  */
+    1, /* unalign_store_cost  */
   },
 };
 
diff --git a/gcc/testsuite/gcc.dg/vect/costmodel/riscv/rvv/pr112387.c 
b/gcc/testsuite/gcc.dg/vect/costmodel/riscv/rvv/pr112387-1.c
similarity index 100%
rename from gcc/testsuite/gcc.dg/vect/costmodel/riscv/rvv/pr112387.c
rename to gcc/testsuite/gcc.dg/vect/costmodel/riscv/rvv/pr112387-1.c
diff --git a/gcc/testsuite/gcc.dg/vect/costmodel/riscv/rvv/pr112387-2.c 
b/gcc/testsuite/gcc.dg/vect/costmodel/riscv/rvv/pr112387-2.c
new file mode 100644
index 00000000000..d9fcad6de9f
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/vect/costmodel/riscv/rvv/pr112387-2.c
@@ -0,0 +1,19 @@
+/* { dg-do compile } */
+/* { dg-options "-march=rv64gcv -mabi=lp64d -mtune=generic-ooo -O3 
-ftree-vectorize -fdump-tree-vect-details" } */
+
+#include <stdint-gcc.h>
+
+void
+f2 (uint64_t *__restrict y, uint64_t *__restrict x,
+    uint64_t *__restrict indices, uint64_t n)
+{
+  for (int64_t i = 0; i < n; ++i)
+    {
+      y[i * 2] = x[indices[i * 2]] + 1;
+      y[i * 2 + 1] = x[indices[i * 2 + 1]] + 2;
+    }
+}
+
+/* { dg-final { scan-tree-dump "Loop contains only SLP stmts" vect } } */
+/* { dg-final { scan-assembler-not "vlseg" } } */
+/* { dg-final { scan-assembler-not "vsseg" } } */
-- 
2.36.3