[gcc r14-3033] Improve -fopt-info-vec for basic-block vectorization

[Richard Biener <rguenth@gcc.gnu.org>]

https://gcc.gnu.org/g:aa63c20420db78ca77ec243af02c7591b88d3b89

commit r14-3033-gaa63c20420db78ca77ec243af02c7591b88d3b89
Author: Richard Biener <rguenther@suse.de>
Date:   Mon Aug 7 13:53:59 2023 +0200

    Improve -fopt-info-vec for basic-block vectorization
    
    We currently dump notes like
    
    flow_lam.f:65:72: optimized: basic block part vectorized using 32 byte vectors
    flow_lam.f:65:72: optimized: basic block part vectorized using 32 byte vectors
    flow_lam.f:65:72: optimized: basic block part vectorized using 32 byte vectors
    flow_lam.f:65:72: optimized: basic block part vectorized using 32 byte vectors
    ..
    
    repeating the same location for multiple instances because we
    clobber vect_location during BB vectorization.  The following
    avoids this, improving things to
    
    flow_lam.f:15:72: optimized: basic block part vectorized using 32 byte vectors
    flow_lam.f:16:72: optimized: basic block part vectorized using 32 byte vectors
    flow_lam.f:17:72: optimized: basic block part vectorized using 32 byte vectors
    flow_lam.f:18:72: optimized: basic block part vectorized using 32 byte vectors
    ...
    
            * tree-vect-slp.cc (vect_slp_region): Save/restore vect_location
            around dumping code.

Diff:
---
 gcc/tree-vect-slp.cc | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/gcc/tree-vect-slp.cc b/gcc/tree-vect-slp.cc
index a1b153035e1..eab3dcd40ec 100644
--- a/gcc/tree-vect-slp.cc
+++ b/gcc/tree-vect-slp.cc
@@ -7496,6 +7496,7 @@ vect_slp_region (vec<basic_block> bbs, vec<data_reference_p> datarefs,
 	      if (instance->subgraph_entries.is_empty ())
 		continue;
 
+	      dump_user_location_t saved_vect_location = vect_location;
 	      vect_location = instance->location ();
 	      if (!unlimited_cost_model (NULL)
 		  && !vect_bb_vectorization_profitable_p
@@ -7505,9 +7506,11 @@ vect_slp_region (vec<basic_block> bbs, vec<data_reference_p> datarefs,
 		    dump_printf_loc (MSG_MISSED_OPTIMIZATION, vect_location,
 				     "not vectorized: vectorization is not "
 				     "profitable.\n");
+		  vect_location = saved_vect_location;
 		  continue;
 		}
 
+	      vect_location = saved_vect_location;
 	      if (!dbg_cnt (vect_slp))
 		continue;
 
@@ -7557,6 +7560,9 @@ vect_slp_region (vec<basic_block> bbs, vec<data_reference_p> datarefs,
 				 "using SLP\n");
 	      vectorized = true;
 
+	      dump_user_location_t saved_vect_location = vect_location;
+	      vect_location = instance->location ();
+
 	      vect_schedule_slp (bb_vinfo, instance->subgraph_entries);
 
 	      unsigned HOST_WIDE_INT bytes;
@@ -7572,6 +7578,8 @@ vect_slp_region (vec<basic_block> bbs, vec<data_reference_p> datarefs,
 				     "basic block part vectorized using "
 				     "variable length vectors\n");
 		}
+
+	      vect_location = saved_vect_location;
 	    }
 	}
       else