diff mbox series

RISC-V: Add LCM delete block predecessors dump information

Message ID 20240125085942.2958647-1-juzhe.zhong@rivai.ai
State Unresolved
Headers
Series RISC-V: Add LCM delete block predecessors dump information |

Checks

Context Check Description
snail/gcc-patch-check warning Git am fail log

Commit Message

juzhe.zhong@rivai.ai Jan. 25, 2024, 8:59 a.m. UTC 
  While looking into PR113469, I notice the LCM delete a vsetvl incorrectly.

This patch add dump information of all predecessors for LCM delete vsetvl block
for better debugging.

Tested no regression.

gcc/ChangeLog:

	* config/riscv/riscv-vsetvl.cc (get_all_predecessors): New function.
	(pre_vsetvl::pre_global_vsetvl_info): Add LCM delete block all predecessors dump information.

---
 gcc/config/riscv/riscv-vsetvl.cc | 42 ++++++++++++++++++++++++++++++++
 1 file changed, 42 insertions(+)

Comments

Kito Cheng Jan. 25, 2024, 9:18 a.m. UTC | #1 
LGTM, it's always good to improve some debug for vsetvli insertion
pass, it's really non-trivial optimization.

On Thu, Jan 25, 2024 at 4:59 PM Juzhe-Zhong <juzhe.zhong@rivai.ai> wrote:
>
> While looking into PR113469, I notice the LCM delete a vsetvl incorrectly.
>
> This patch add dump information of all predecessors for LCM delete vsetvl block
> for better debugging.
>
> Tested no regression.
>
> gcc/ChangeLog:
>
>         * config/riscv/riscv-vsetvl.cc (get_all_predecessors): New function.
>         (pre_vsetvl::pre_global_vsetvl_info): Add LCM delete block all predecessors dump information.
>
> ---
>  gcc/config/riscv/riscv-vsetvl.cc | 42 ++++++++++++++++++++++++++++++++
>  1 file changed, 42 insertions(+)
>
> diff --git a/gcc/config/riscv/riscv-vsetvl.cc b/gcc/config/riscv/riscv-vsetvl.cc
> index 72c5a127d9e..da258b964fc 100644
> --- a/gcc/config/riscv/riscv-vsetvl.cc
> +++ b/gcc/config/riscv/riscv-vsetvl.cc
> @@ -654,6 +654,31 @@ invalid_opt_bb_p (basic_block cfg_bb)
>    return false;
>  }
>
> +/* Get all predecessors of BB.  */
> +static hash_set<basic_block>
> +get_all_predecessors (basic_block bb)
> +{
> +  hash_set<basic_block> blocks;
> +  auto_vec<basic_block> work_list;
> +  hash_set<basic_block> visited_list;
> +  work_list.safe_push (bb);
> +
> +  while (!work_list.is_empty ())
> +    {
> +      basic_block new_bb = work_list.pop ();
> +      visited_list.add (new_bb);
> +      edge e;
> +      edge_iterator ei;
> +      FOR_EACH_EDGE (e, ei, new_bb->preds)
> +       {
> +         if (!visited_list.contains (e->src))
> +           work_list.safe_push (e->src);
> +         blocks.add (e->src);
> +       }
> +    }
> +  return blocks;
> +}
> +
>  /* This flags indicates the minimum demand of the vl and vtype values by the
>     RVV instruction. For example, DEMAND_RATIO_P indicates that this RVV
>     instruction only needs the SEW/LMUL ratio to remain the same, and does not
> @@ -3142,6 +3167,23 @@ pre_vsetvl::pre_global_vsetvl_info ()
>        const vsetvl_block_info &block_info = get_block_info (info.get_bb ());
>        gcc_assert (block_info.get_entry_info () == info);
>        info.set_delete ();
> +      if (dump_file && (dump_flags & TDF_DETAILS))
> +       {
> +         fprintf (dump_file,
> +                  "\nLCM deleting vsetvl of block %d, it has predecessors: \n",
> +                  bb->index ());
> +         hash_set<basic_block> all_preds
> +           = get_all_predecessors (bb->cfg_bb ());
> +         int i = 0;
> +         for (const auto pred : all_preds)
> +           {
> +             fprintf (dump_file, "%d ", pred->index);
> +             i++;
> +             if (i % 32 == 0)
> +               fprintf (dump_file, "\n");
> +           }
> +         fprintf (dump_file, "\n");
> +       }
>      }
>
>    /* Remove vsetvl infos if all precessors are available to the block.  */
> --
> 2.36.3
>
diff mbox series

Patch

diff --git a/gcc/config/riscv/riscv-vsetvl.cc b/gcc/config/riscv/riscv-vsetvl.cc
index 72c5a127d9e..da258b964fc 100644
--- a/gcc/config/riscv/riscv-vsetvl.cc
+++ b/gcc/config/riscv/riscv-vsetvl.cc
@@ -654,6 +654,31 @@  invalid_opt_bb_p (basic_block cfg_bb)
   return false;
 }
 
+/* Get all predecessors of BB.  */
+static hash_set<basic_block>
+get_all_predecessors (basic_block bb)
+{
+  hash_set<basic_block> blocks;
+  auto_vec<basic_block> work_list;
+  hash_set<basic_block> visited_list;
+  work_list.safe_push (bb);
+
+  while (!work_list.is_empty ())
+    {
+      basic_block new_bb = work_list.pop ();
+      visited_list.add (new_bb);
+      edge e;
+      edge_iterator ei;
+      FOR_EACH_EDGE (e, ei, new_bb->preds)
+	{
+	  if (!visited_list.contains (e->src))
+	    work_list.safe_push (e->src);
+	  blocks.add (e->src);
+	}
+    }
+  return blocks;
+}
+
 /* This flags indicates the minimum demand of the vl and vtype values by the
    RVV instruction. For example, DEMAND_RATIO_P indicates that this RVV
    instruction only needs the SEW/LMUL ratio to remain the same, and does not
@@ -3142,6 +3167,23 @@  pre_vsetvl::pre_global_vsetvl_info ()
       const vsetvl_block_info &block_info = get_block_info (info.get_bb ());
       gcc_assert (block_info.get_entry_info () == info);
       info.set_delete ();
+      if (dump_file && (dump_flags & TDF_DETAILS))
+	{
+	  fprintf (dump_file,
+		   "\nLCM deleting vsetvl of block %d, it has predecessors: \n",
+		   bb->index ());
+	  hash_set<basic_block> all_preds
+	    = get_all_predecessors (bb->cfg_bb ());
+	  int i = 0;
+	  for (const auto pred : all_preds)
+	    {
+	      fprintf (dump_file, "%d ", pred->index);
+	      i++;
+	      if (i % 32 == 0)
+		fprintf (dump_file, "\n");
+	    }
+	  fprintf (dump_file, "\n");
+	}
     }
 
   /* Remove vsetvl infos if all precessors are available to the block.  */