diff mbox

[5/6] Record initialization statements and only insert it for valid chains

Message ID VI1PR0802MB21761D2DC5558BBFBC00E0D1E7E20@VI1PR0802MB2176.eurprd08.prod.outlook.com
State New
Headers show

Commit Message

Bin Cheng May 12, 2017, 11:28 a.m. UTC 
Hi,
This patch caches initialization statements and only inserts it for valid chains.
Looks like current code even inserts such stmts for invalid chains which will be
deleted as dead code afterwards.

Bootstrap and test on x86_64 and AArch64, is it OK?

Thanks,
bin
2017-05-10  Bin Cheng  <bin.cheng@arm.com>

	* tree-predcom.c (struct chain): New field init_seq.
	(prepare_initializers_chain): Record intialization stmts in above
	field.  Discard it if chain is invalid.
	(insert_init_seqs): New function.
	(tree_predictive_commoning_loop): Call insert_init_seqs.
From db10e77e52ad44416edc08f9789faabef911a9d8 Mon Sep 17 00:00:00 2001
From: Bin Cheng <binche01@e108451-lin.cambridge.arm.com>
Date: Mon, 24 Apr 2017 14:48:12 +0100
Subject: [PATCH 5/6] chain-init-seq-20170102.txt

---
 gcc/tree-predcom.c | 25 ++++++++++++++++++++++++-
 1 file changed, 24 insertions(+), 1 deletion(-)
diff mbox

Patch

diff --git a/gcc/tree-predcom.c b/gcc/tree-predcom.c
index 0b7811a..f73d869 100644
--- a/gcc/tree-predcom.c
+++ b/gcc/tree-predcom.c
@@ -296,6 +296,9 @@  typedef struct chain
   /* Initializers for the variables.  */
   vec<tree> inits;
 
+  /* gimple stmts intializing the initial variables of the chain.  */
+  gimple_seq init_seq;
+
   /* True if there is a use of a variable with the maximal distance
      that comes after the root in the loop.  */
   unsigned has_max_use_after : 1;
@@ -2454,12 +2457,14 @@  prepare_initializers_chain (struct loop *loop, chain_p chain)
       init = ref_at_iteration (dr, (int) i - n, &stmts);
       if (!chain->all_always_accessed && tree_could_trap_p (init))
 	{
+	  if (chain->init_seq)
+	    gimple_seq_discard (chain->init_seq);
 	  gimple_seq_discard (stmts);
 	  return false;
 	}
 
       if (stmts)
-	gsi_insert_seq_on_edge_immediate (entry, stmts);
+	gimple_seq_add_seq (&chain->init_seq, stmts);
 
       chain->inits[i] = init;
     }
@@ -2489,6 +2494,22 @@  prepare_initializers (struct loop *loop, vec<chain_p> chains)
     }
 }
 
+/* Insert all initializing gimple stmts into loop's entry edge.  */
+
+static void
+insert_init_seqs (struct loop *loop, vec<chain_p> chains)
+{
+  unsigned i;
+  edge entry = loop_preheader_edge (loop);
+
+  for (i = 0; i < chains.length (); ++i)
+    if (chains[i]->init_seq)
+      {
+	gsi_insert_seq_on_edge_immediate (entry, chains[i]->init_seq);
+	chains[i]->init_seq = NULL;
+      }
+}
+
 /* Performs predictive commoning for LOOP.  Returns true if LOOP was
    unrolled.  */
 
@@ -2571,6 +2592,8 @@  tree_predictive_commoning_loop (struct loop *loop)
   /* Try to combine the chains that are always worked with together.  */
   try_combine_chains (&chains);
 
+  insert_init_seqs (loop, chains);
+
   if (dump_file && (dump_flags & TDF_DETAILS))
     {
       fprintf (dump_file, "Before commoning:\n\n");