From: Richard Biener <rguenther@suse.de>
Date: Wed, 2 Jul 2025 11:44:59 +0000 (+0200)
Subject: Do not query further vector epilogues after a masked epilogue
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=57d30924e2b3887a1aedc6102daa67bc3272ace7;p=thirdparty%2Fgcc.git

Do not query further vector epilogues after a masked epilogue

When doing --param vect-partial-vector-usage=1 we'd continue querying
the target whether it wants more vector epilogues, but when it comes
back with a suggestion we then might iterate endlessly.  Do not
even ask the target when we decided for the last epilogue to be
one with partial vectors.

	PR tree-optimization/120927
	* tree-vect-loop.cc (vect_analyze_loop): Stop querying
	further epilogues after one with partial vectors.
---

diff --git a/gcc/tree-vect-loop.cc b/gcc/tree-vect-loop.cc
index 575987e4bf0..2782d61a5fc 100644
--- a/gcc/tree-vect-loop.cc
+++ b/gcc/tree-vect-loop.cc
@@ -3792,6 +3792,7 @@ vect_analyze_loop (class loop *loop, gimple *loop_vectorized_call,
       /* When we selected a first vectorized epilogue, see if the target
 	 suggests to have another one.  */
       if (!unlimited_cost_model (loop)
+	  && !LOOP_VINFO_USING_PARTIAL_VECTORS_P (orig_loop_vinfo)
 	  && (orig_loop_vinfo->vector_costs->suggested_epilogue_mode ()
 	      != VOIDmode))
 	{