tree-optimization/102847 - properly cost VMAT_INVARIANT loads

Message ID 17snp8s6-1058-n7r-nos-60o0n6o3o826@fhfr.qr
State Committed
Commit 7878981f1d44b4c9bb6c4a3137b37f06c725b73d
Headers
Series tree-optimization/102847 - properly cost VMAT_INVARIANT loads |

Commit Message

Richard Biener Oct. 21, 2021, 9:21 a.m. UTC
  The following adds proper costing of VMAT_INVARIANT loads, avoiding
to ask the target about the cost of an unsupported vector load cost
which we won't emit anyway.

Bootstrapped and tested on x86_64-unknown-linux-gnu, pushed.

2021-10-21  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/102847
	* tree-vect-stmts.c (vect_model_load_cost): Explicitely
	handle VMAT_INVARIANT as a splat in the prologue.
---
 gcc/tree-vect-stmts.c | 7 +++++++
 1 file changed, 7 insertions(+)
  

Patch

diff --git a/gcc/tree-vect-stmts.c b/gcc/tree-vect-stmts.c
index 9cbc1af4cc9..8f527452bd0 100644
--- a/gcc/tree-vect-stmts.c
+++ b/gcc/tree-vect-stmts.c
@@ -1191,6 +1191,13 @@  vect_model_load_cost (vec_info *vinfo,
 				       ncopies * assumed_nunits,
 				       scalar_load, stmt_info, 0, vect_body);
     }
+  else if (memory_access_type == VMAT_INVARIANT)
+    {
+      /* Invariant loads will ideally be hoisted and splat to a vector.  */
+      prologue_cost += record_stmt_cost (cost_vec, 1,
+					 scalar_to_vec, stmt_info, 0,
+					 vect_prologue);
+    }
   else
     vect_get_load_cost (vinfo, stmt_info, ncopies,
 			alignment_support_scheme, misalignment, first_stmt_p,