[gcc(refs/vendors/vrull/heads/slp-improvements)] Slightly restrict preconditions for vect_slp_optimize_permutes

[Philipp Tomsich]

https://gcc.gnu.org/g:5c262464666155ff596dd9cb081fa18062164320

commit 5c262464666155ff596dd9cb081fa18062164320
Author: Manolis Tsamis <manolis.tsamis@vrull.eu>
Date:   Fri Dec 1 11:07:56 2023 +0100

    Slightly restrict preconditions for vect_slp_optimize_permutes

Diff:
---
 gcc/tree-vect-slp.cc | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/gcc/tree-vect-slp.cc b/gcc/tree-vect-slp.cc
index 20acfba887d..30ac656a0af 100644
--- a/gcc/tree-vect-slp.cc
+++ b/gcc/tree-vect-slp.cc
@@ -8144,7 +8144,8 @@ recognise_perm_binop_perm_pattern (gassign *stmt, enum tree_code *binop1,
     return false;
 
   if (gimple_assign_rhs1 (bop1) != gimple_assign_rhs1 (bop2)
-      || gimple_assign_rhs2 (bop1) != gimple_assign_rhs2 (bop2))
+      || gimple_assign_rhs2 (bop1) != gimple_assign_rhs2 (bop2)
+      || bop1 == bop2)
     return false;
 
   tree src1_perm = gimple_assign_rhs1 (bop1);
@@ -8153,8 +8154,8 @@ recognise_perm_binop_perm_pattern (gassign *stmt, enum tree_code *binop1,
   gassign *perm1, *perm2;
   if (!(perm1 = get_tree_def(src1_perm, false))
       || !(perm2 = get_tree_def(src2_perm, false))
-      || num_imm_uses (src1_perm) > 2
-      || num_imm_uses (src2_perm) > 2
+      || num_imm_uses (src1_perm) != 2
+      || num_imm_uses (src2_perm) != 2
       || gimple_assign_rhs_code (perm1) != VEC_PERM_EXPR
       || gimple_assign_rhs_code (perm2) != VEC_PERM_EXPR
       || gimple_assign_rhs1 (perm1) != gimple_assign_rhs2 (perm1)