]> git.ipfire.org Git - thirdparty/gcc.git/commitdiff
VECT: Fix ICE of variable stride on strieded load/store with SELECT_VL loop control.
authorJu-Zhe Zhong <juzhe.zhong@rivai.ai>
Thu, 6 Jul 2023 06:51:35 +0000 (14:51 +0800)
committerPan Li <pan2.li@intel.com>
Thu, 6 Jul 2023 07:12:13 +0000 (15:12 +0800)
Hi, Richi.

Sorry for making mistake on LEN_MASK_GATHER_LOAD/LEN_MASK_SCATTER_STORE
with SELECT_VL loop control.

Consider this following case:
  void __attribute__ ((noinline, noclone))                                     \
  f_##DATA_TYPE##_##BITS (DATA_TYPE *restrict dest, DATA_TYPE *restrict src,   \
  INDEX##BITS stride, INDEX##BITS n)                   \
  {                                                                            \
    for (INDEX##BITS i = 0; i < n; ++i)                                        \
      dest[i] += src[i * stride];                                              \
  }

When "stride" is a constant, current flow works fine.
However, when "stride" is a variable. It causes an ICE:
...
_96 = .SELECT_VL (ivtmp_94, 4);
...
ivtmp_78 = ((sizetype) _39 * (sizetype) _96) * 4;
vect__11.69_87 = .LEN_MASK_GATHER_LOAD (vectp_src.67_85, _84, 4, { 0, 0, 0, 0 }, { -1, -1, -1, -1 }, _96, 0);
...
vectp_src.67_86 = vectp_src.67_85 + ivtmp_78;

Becase the IR: ivtmp_78 = ((sizetype) _39 * (sizetype) _96) * 4;

Instead, I split the IR into:

step_stride = _39
step = step_stride * 4
ivtmp_78 = step * _96

Thanks.

gcc/ChangeLog:

* tree-vect-stmts.cc (vect_get_strided_load_store_ops): Fix ICE.

gcc/tree-vect-stmts.cc

index c10a4be60eb9c8c6b968fd48c35aeefc690c504f..10e71178ce79cf70d51c44618c5de09c7c256ee8 100644 (file)
@@ -3176,10 +3176,8 @@ vect_get_strided_load_store_ops (stmt_vec_info stmt_info,
        = fold_build2 (MULT_EXPR, sizetype,
                       fold_convert (sizetype, unshare_expr (DR_STEP (dr))),
                       loop_len);
-      tree bump = make_temp_ssa_name (sizetype, NULL, "ivtmp");
-      gassign *assign = gimple_build_assign (bump, tmp);
-      gsi_insert_before (gsi, assign, GSI_SAME_STMT);
-      *dataref_bump = bump;
+      *dataref_bump = force_gimple_operand_gsi (gsi, tmp, true, NULL_TREE, true,
+                                               GSI_SAME_STMT);
     }
   else
     {