{"id":2230223,"url":"http://patchwork.ozlabs.org/api/1.1/patches/2230223/?format=json","web_url":"http://patchwork.ozlabs.org/project/gcc/patch/20260429133156.8F3994BB3BE5@sourceware.org/","project":{"id":17,"url":"http://patchwork.ozlabs.org/api/1.1/projects/17/?format=json","name":"GNU Compiler Collection","link_name":"gcc","list_id":"gcc-patches.gcc.gnu.org","list_email":"gcc-patches@gcc.gnu.org","web_url":null,"scm_url":null,"webscm_url":null},"msgid":"<20260429133156.8F3994BB3BE5@sourceware.org>","date":"2026-04-29T13:31:19","name":"[x86,v2] override vector_costs::better_epilogue_loop_than_p","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"1bfea2635054d9b572aba01890c324f5135bcbf6","submitter":{"id":4338,"url":"http://patchwork.ozlabs.org/api/1.1/people/4338/?format=json","name":"Richard Biener","email":"rguenther@suse.de"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/gcc/patch/20260429133156.8F3994BB3BE5@sourceware.org/mbox/","series":[{"id":502061,"url":"http://patchwork.ozlabs.org/api/1.1/series/502061/?format=json","web_url":"http://patchwork.ozlabs.org/project/gcc/list/?series=502061","date":"2026-04-29T13:31:19","name":"[x86,v2] override vector_costs::better_epilogue_loop_than_p","version":2,"mbox":"http://patchwork.ozlabs.org/series/502061/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/2230223/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/2230223/checks/","tags":{},"headers":{"Return-Path":"","X-Original-To":["incoming@patchwork.ozlabs.org","gcc-patches@gcc.gnu.org"],"Delivered-To":["patchwork-incoming@legolas.ozlabs.org","gcc-patches@gcc.gnu.org"],"Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (1024-bit key;\n unprotected) header.d=suse.de header.i=@suse.de header.a=rsa-sha256\n header.s=susede2_rsa header.b=a4DqbqK1;\n\tdkim=pass header.d=suse.de header.i=@suse.de header.a=ed25519-sha256\n header.s=susede2_ed25519 header.b=hkJZeZDi;\n\tdkim=pass (1024-bit key) header.d=suse.de header.i=@suse.de\n header.a=rsa-sha256 header.s=susede2_rsa header.b=Pl5EJ/m1;\n\tdkim=neutral header.d=suse.de header.i=@suse.de header.a=ed25519-sha256\n header.s=susede2_ed25519 header.b=Oq1JY/wD;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=gcc.gnu.org\n (client-ip=2620:52:6:3111::32; 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charset=US-ASCII","X-Spamd-Result":"default: False [-1.80 / 50.00]; BAYES_HAM(-3.00)[100.00%];\n MISSING_MID(2.50)[]; NEURAL_HAM_LONG(-1.00)[-1.000];\n NEURAL_HAM_SHORT(-0.20)[-0.998]; MIME_GOOD(-0.10)[text/plain];\n RCVD_COUNT_ZERO(0.00)[0]; MISSING_XM_UA(0.00)[];\n ARC_NA(0.00)[]; RCPT_COUNT_TWO(0.00)[2]; FROM_HAS_DN(0.00)[];\n TO_MATCH_ENVRCPT_ALL(0.00)[];\n DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519];\n FROM_EQ_ENVFROM(0.00)[]; TO_DN_NONE(0.00)[];\n MIME_TRACE(0.00)[0:+]","X-BeenThere":"gcc-patches@gcc.gnu.org","X-Mailman-Version":"2.1.30","Precedence":"list","List-Id":"Gcc-patches mailing list ","List-Unsubscribe":",\n ","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n ","Errors-To":"gcc-patches-bounces~incoming=patchwork.ozlabs.org@gcc.gnu.org","Message-Id":"<20260429133156.8F3994BB3BE5@sourceware.org>"},"content":"The following resolves the gcc.target/i386/vect-epilogues-3.c failure\nwhen --param ix86-vect-compare-costs=1 is specified. When the target\nrequests multiple epilogues to be used and the new candidate is the\nepilogue of choice of the currently prevailing epilogue keep that.\n\nv2:\n\nBut avoid doing so if the new candidate uses a vectorization factor\nof one which should be an optimal vector epilog. This avoids\nregressing gcc.dg/vect/costmodel/x86_64/costmodel-pr122573.c\n\nBootstrapped and tested on x86_64-unknown-linux-gnu.\n\nRichard.\n\n\t* config/i386/i386.cc (ix86_vector_costs::better_epilogue_loop_than_p):\n\tNew. If the other loop suggests this as epilog prefer other.\n---\n gcc/config/i386/i386.cc | 21 +++++++++++++++++++++\n 1 file changed, 21 insertions(+)","diff":"diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc\nindex 6d34b23c2d6..e6aa31b6b24 100644\n--- a/gcc/config/i386/i386.cc\n+++ b/gcc/config/i386/i386.cc\n@@ -26126,6 +26126,8 @@ public:\n \t\t\t vect_cost_model_location where) override;\n void finish_cost (const vector_costs *) override;\n bool better_main_loop_than_p (const vector_costs *) const override;\n+ bool better_epilogue_loop_than_p (const vector_costs *other,\n+\t\t\t\t loop_vec_info main_loop) const;\n \n private:\n \n@@ -27007,6 +27009,25 @@ ix86_vector_costs::better_main_loop_than_p (const vector_costs *other) const\n return vector_costs::better_main_loop_than_p (other);\n }\n \n+/* Return true if THIS should be preferred over OTHER as epilog vector\n+ loop when vectorizing MAIN_LOOP. */\n+\n+bool\n+ix86_vector_costs::better_epilogue_loop_than_p (const vector_costs *other,\n+\t\t\t\t\t\tloop_vec_info main_loop) const\n+{\n+ loop_vec_info this_loop_info = as_a (this->vinfo ());\n+ /* The x86 target allows for multiple vector epilogues, if THIS is\n+ the suggested epilog mode of OTHER then keep the latter unless\n+ THIS has a VF of one which means no further epilog needed. */\n+ int tem;\n+ if (known_gt (LOOP_VINFO_VECT_FACTOR (this_loop_info), 1U)\n+ && (GET_MODE_SIZE (other->suggested_epilogue_mode (tem))\n+\t == GET_MODE_SIZE (this_loop_info->vector_mode)))\n+ return false;\n+ return vector_costs::better_epilogue_loop_than_p (other, main_loop);\n+}\n+\n /* Validate target specific memory model bits in VAL. */\n \n static unsigned HOST_WIDE_INT\n","prefixes":["x86","v2"]}