On Sat, Aug 15, 2026 at 6:38 AM Andrea Pinski <[email protected]> wrote: > > On Fri, Aug 14, 2026 at 2:13 PM H.J. Lu <[email protected]> wrote: > > > > Add EDGE_PURE_SIBCALL to mark an edge which has a pure sibcall without > > other control flow transfers. > > I don't like the pure part of the name, especially considered pure for > a function that already exists. > Maybe ONLY would be better.
Here is the v2 patch to add EDGE_ONLY_SIBCALL. -- H.J. --- Add EDGE_ONLY_SIBCALL to mark an edge which has a sibcall without other control flow transfers. * basic-block.h (EDGE_ONLY_SIBCALL): New. * cfgbuild.cc (make_edges): Use EDGE_ONLY_SIBCALL to make a sibcall edge. * cfgexpand.cc (expand_gimple_tailcall): Likewise. * cfgrtl.cc (purge_dead_edges): Assert EDGE_ONLY_SIBCALL.
From db066051d17b87ff59845c33a9ef3d0b9384e3f6 Mon Sep 17 00:00:00 2001 From: "H.J. Lu" <[email protected]> Date: Thu, 13 Aug 2026 07:54:40 +0800 Subject: [PATCH v2] Add EDGE_ONLY_SIBCALL Add EDGE_ONLY_SIBCALL to mark an edge which has a sibcall without other control flow transfers. * basic-block.h (EDGE_ONLY_SIBCALL): New. * cfgbuild.cc (make_edges): Use EDGE_ONLY_SIBCALL to make a sibcall edge. * cfgexpand.cc (expand_gimple_tailcall): Likewise. * cfgrtl.cc (purge_dead_edges): Assert EDGE_ONLY_SIBCALL. Signed-off-by: H.J. Lu <[email protected]> --- gcc/basic-block.h | 3 +++ gcc/cfgbuild.cc | 2 +- gcc/cfgexpand.cc | 3 +-- gcc/cfgrtl.cc | 3 +-- 4 files changed, 6 insertions(+), 5 deletions(-) diff --git a/gcc/basic-block.h b/gcc/basic-block.h index 08082447568..43863d84ef3 100644 --- a/gcc/basic-block.h +++ b/gcc/basic-block.h @@ -69,6 +69,9 @@ enum cfg_edge_flags { #define EDGE_COMPLEX \ (EDGE_ABNORMAL | EDGE_ABNORMAL_CALL | EDGE_EH | EDGE_PRESERVE) +/* An edge has a sibcall without other control flow transfers. */ +#define EDGE_ONLY_SIBCALL (EDGE_ABNORMAL | EDGE_SIBCALL) + struct GTY(()) rtl_bb_info { /* The first insn of the block is embedded into bb->il.x. */ /* The last insn of the block. */ diff --git a/gcc/cfgbuild.cc b/gcc/cfgbuild.cc index 3ed1eca694b..ee80d35cc13 100644 --- a/gcc/cfgbuild.cc +++ b/gcc/cfgbuild.cc @@ -315,7 +315,7 @@ make_edges (basic_block min, basic_block max, int update_p) in the first place. */ if (code == CALL_INSN && SIBLING_CALL_P (insn)) cached_make_edge (edge_cache, bb, EXIT_BLOCK_PTR_FOR_FN (cfun), - EDGE_SIBCALL | EDGE_ABNORMAL); + EDGE_ONLY_SIBCALL); /* If this is a CALL_INSN, then mark it as reaching the active EH handler for this CALL_INSN. If we're handling non-call diff --git a/gcc/cfgexpand.cc b/gcc/cfgexpand.cc index 128cfc77684..dc2e5af6c26 100644 --- a/gcc/cfgexpand.cc +++ b/gcc/cfgexpand.cc @@ -4578,8 +4578,7 @@ expand_gimple_tailcall (basic_block bb, gcall *stmt, bool *can_fallthru, delete_insn (NEXT_INSN (last)); } - e = make_edge (bb, EXIT_BLOCK_PTR_FOR_FN (cfun), EDGE_ABNORMAL - | EDGE_SIBCALL); + e = make_edge (bb, EXIT_BLOCK_PTR_FOR_FN (cfun), EDGE_ONLY_SIBCALL); e->probability = probability; head_end_for_bb[bb->index].second = last; update_bb_for_insn_chain (head_end_for_bb[bb->index].first, diff --git a/gcc/cfgrtl.cc b/gcc/cfgrtl.cc index 474b84a0893..c1d92267afd 100644 --- a/gcc/cfgrtl.cc +++ b/gcc/cfgrtl.cc @@ -3370,8 +3370,7 @@ purge_dead_edges (basic_block bb) have created the sibcall in the first place. Second, there should of course never have been a fallthru edge. */ gcc_assert (single_succ_p (bb)); - gcc_assert (single_succ_edge (bb)->flags - == (EDGE_SIBCALL | EDGE_ABNORMAL)); + gcc_assert (single_succ_edge (bb)->flags == EDGE_ONLY_SIBCALL); return false; } -- 2.55.0
