commit: 3c997ffed4de1d98d745b63d1ef95342800c52f1 Author: Sam James <sam <AT> gentoo <DOT> org> AuthorDate: Mon Apr 7 18:02:01 2025 +0000 Commit: Sam James <sam <AT> gentoo <DOT> org> CommitDate: Mon Apr 7 18:02:01 2025 +0000 URL: https://gitweb.gentoo.org/proj/gcc-patches.git/commit/?id=3c997ffe
15.0.0: drop 88_all_PR119614.patch patch, merged upstream Signed-off-by: Sam James <sam <AT> gentoo.org> 15.0.0/gentoo/88_all_PR119614.patch | 195 ------------------------------------ 15.0.0/gentoo/README.history | 2 +- 2 files changed, 1 insertion(+), 196 deletions(-) diff --git a/15.0.0/gentoo/88_all_PR119614.patch b/15.0.0/gentoo/88_all_PR119614.patch deleted file mode 100644 index 753002f..0000000 --- a/15.0.0/gentoo/88_all_PR119614.patch +++ /dev/null @@ -1,195 +0,0 @@ -https://inbox.sourceware.org/gcc-patches/Z%2FNiBLuNG0iaDHwi@tucnak/ - -From de8e860faaee40f7f34a66440e8f98ed97219a89 Mon Sep 17 00:00:00 2001 -Message-ID: <de8e860faaee40f7f34a66440e8f98ed97219a89.1744008820.git....@gentoo.org> -From: Jakub Jelinek <[email protected]> -Date: Mon, 7 Apr 2025 07:26:28 +0200 -Subject: [PATCH] tailc: Extend the IPA-VRP workaround [PR119614] - -Hi! - -The IPA-VRP workaround in the tailc/musttail passes was just comparing -the singleton constant from a tail call candidate return with the ret_val. -This unfortunately doesn't work in the following testcase, where we have - <bb 5> [local count: 152205050]: - baz (); [must tail call] - goto <bb 4>; [100.00%] - - <bb 6> [local count: 762356696]: - _8 = foo (); - - <bb 7> [local count: 1073741824]: - # _3 = PHI <0B(4), _8(6)> - return _3; -and in the unreduced testcase even more PHIs before we reach the return -stmt. - -Normally when the call has lhs, whenever we follow a (non-EH) successor -edge, it calls propagate_through_phis and that walks the PHIs in the -destination bb of the edge and when it sees a PHI whose argument matches -that of the currently tracked value (ass_var), it updates ass_var to -PHI result of that PHI. I think it is theoretically dangerous that it -picks the first one, perhaps there could be multiple PHIs, so perhaps safer -would be walk backwards from the return value up to the call. - -Anyway, this PR is about the IPA-VRP workaround, there ass_var is NULL -because the potential tail call has no lhs, but ret_var is not TREE_CONSTANT -but SSA_NAME with PHI as SSA_NAME_DEF_STMT. The following patch handles -it by pushing the edges we've walked through when ass_var is NULL into a -vector and if ret_var is SSA_NAME set to PHI result, it attempts to walk -back from the ret_var through arguments of PHIs corresponding to the -edges we've walked back until we reach a constant and compare that constant -against the singleton value as well. - -Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? - -2025-04-07 Jakub Jelinek <[email protected]> - - PR tree-optimization/119614 - * tree-tailcall.cc (find_tail_calls): Remember edges which have been - walked through if !ass_var. Perform IPA-VRP workaround even when - ret_var is not TREE_CONSTANT, in that case check in a loop if it is - a PHI result and in that case look at the PHI argument from - corresponding edge in the edge vector. - - * g++.dg/opt/pr119613.C: Change { c || c++11 } in obviously C++ only - test to just c++11. - * g++.dg/opt/pr119614.C: New test. ---- - gcc/testsuite/g++.dg/opt/pr119613.C | 2 +- - gcc/testsuite/g++.dg/opt/pr119614.C | 30 ++++++++++++++++++ - gcc/tree-tailcall.cc | 47 +++++++++++++++++++++++++---- - 3 files changed, 72 insertions(+), 7 deletions(-) - create mode 100644 gcc/testsuite/g++.dg/opt/pr119614.C - -diff --git a/gcc/testsuite/g++.dg/opt/pr119613.C b/gcc/testsuite/g++.dg/opt/pr119613.C -index 432a30cdcdb0..2ced2e8fa2a0 100644 ---- a/gcc/testsuite/g++.dg/opt/pr119613.C -+++ b/gcc/testsuite/g++.dg/opt/pr119613.C -@@ -1,5 +1,5 @@ - // PR middle-end/119613 --// { dg-do compile { target { musttail && { c || c++11 } } } } -+// { dg-do compile { target { musttail && c++11 } } } - // { dg-options "-O0" } - - struct S { S () {} }; -diff --git a/gcc/testsuite/g++.dg/opt/pr119614.C b/gcc/testsuite/g++.dg/opt/pr119614.C -new file mode 100644 -index 000000000000..cb73fc3ec09d ---- /dev/null -+++ b/gcc/testsuite/g++.dg/opt/pr119614.C -@@ -0,0 +1,30 @@ -+// PR tree-optimization/119614 -+// { dg-do compile { target musttail } } -+// { dg-options "-O2" } -+ -+struct S {} b; -+char *foo (); -+int e, g; -+void bar (); -+void corge (S); -+ -+[[gnu::noinline]] char * -+baz () -+{ -+ bar (); -+ return 0; -+} -+ -+const char * -+qux () -+{ -+ if (e) -+ { -+ S a = b; -+ corge (a); -+ if (g) -+ return 0; -+ [[gnu::musttail]] return baz (); -+ } -+ return foo (); -+} -diff --git a/gcc/tree-tailcall.cc b/gcc/tree-tailcall.cc -index c8740f9353e2..f51bb970e329 100644 ---- a/gcc/tree-tailcall.cc -+++ b/gcc/tree-tailcall.cc -@@ -920,6 +920,7 @@ find_tail_calls (basic_block bb, struct tailcall **ret, bool only_musttail, - auto_bitmap to_move_defs; - auto_vec<gimple *> to_move_stmts; - bool is_noreturn = gimple_call_noreturn_p (call); -+ auto_vec<edge> edges; - - abb = bb; - agsi = gsi; -@@ -933,6 +934,8 @@ find_tail_calls (basic_block bb, struct tailcall **ret, bool only_musttail, - { - edge e = single_non_eh_succ_edge (abb); - ass_var = propagate_through_phis (ass_var, e); -+ if (!ass_var) -+ edges.safe_push (e); - abb = e->dest; - agsi = gsi_start_bb (abb); - } -@@ -1040,9 +1043,7 @@ find_tail_calls (basic_block bb, struct tailcall **ret, bool only_musttail, - /* If IPA-VRP proves called function always returns a singleton range, - the return value is replaced by the only value in that range. - For tail call purposes, pretend such replacement didn't happen. */ -- if (ass_var == NULL_TREE -- && !tail_recursion -- && TREE_CONSTANT (ret_var)) -+ if (ass_var == NULL_TREE && !tail_recursion) - if (tree type = gimple_range_type (call)) - if (tree callee = gimple_call_fndecl (call)) - if ((INTEGRAL_TYPE_P (type) -@@ -1052,9 +1053,43 @@ find_tail_calls (basic_block bb, struct tailcall **ret, bool only_musttail, - type) - && useless_type_conversion_p (TREE_TYPE (ret_var), type) - && ipa_return_value_range (val, callee) -- && val.singleton_p (&valr) -- && operand_equal_p (ret_var, valr, 0)) -- ok = true; -+ && val.singleton_p (&valr)) -+ { -+ tree rv = ret_var; -+ unsigned int i = edges.length (); -+ /* If ret_var is equal to valr, we can tail optimize. */ -+ if (operand_equal_p (ret_var, valr, 0)) -+ ok = true; -+ else -+ /* Otherwise, if ret_var is a PHI result, try to find out -+ if valr isn't propagated through PHIs on the path from -+ call's bb to SSA_NAME_DEF_STMT (ret_var)'s bb. */ -+ while (TREE_CODE (rv) == SSA_NAME -+ && gimple_code (SSA_NAME_DEF_STMT (rv)) == GIMPLE_PHI) -+ { -+ tree nrv = NULL_TREE; -+ gimple *g = SSA_NAME_DEF_STMT (rv); -+ for (; i; --i) -+ { -+ if (edges[i - 1]->dest == gimple_bb (g)) -+ { -+ nrv -+ = gimple_phi_arg_def_from_edge (g, -+ edges[i - 1]); -+ --i; -+ break; -+ } -+ } -+ if (nrv == NULL_TREE) -+ break; -+ if (operand_equal_p (nrv, valr, 0)) -+ { -+ ok = true; -+ break; -+ } -+ rv = nrv; -+ } -+ } - if (!ok) - { - maybe_error_musttail (call, - -base-commit: 8fbe7d24373556d40886c7c00e9e2be5d9718c55 --- -2.49.0 - diff --git a/15.0.0/gentoo/README.history b/15.0.0/gentoo/README.history index 51cd6a7..c3166a6 100644 --- a/15.0.0/gentoo/README.history +++ b/15.0.0/gentoo/README.history @@ -5,7 +5,7 @@ - 85_all_combine-Optimise-distribute_links-search-PR116398.patch - 86_all_combine-Limit-insn-searchs-for-2-2-combinations-PR11.patch - 87_all_simplify-rtx-Fix-shortcut-for-vector-eq-ne.patch - U 88_all_PR119614.patch + - 88_all_PR119614.patch 53 7 April 2025
