From b738a63e528db410a1c51fc27db37fe22f0cb397 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Wed, 15 May 2024 19:57:22 -0700 Subject: Enable musttail tail conversion even when not optimizing Enable the tailcall optimization for non optimizing builds, but in this case only checks calls that have the musttail attribute set. This makes musttail work without optimization. This is done with a new late musttail pass that is only active when not optimizing. The new pass relies on tree-cfg to discover musttails. This avoids a ~0.8% compiler run time penalty at -O0. gcc/ChangeLog: PR c/83324 * function.h (struct function): Add has_musttail. * lto-streamer-in.cc (input_struct_function_base): Stream has_musttail. * lto-streamer-out.cc (output_struct_function_base): Dito. * passes.def (pass_musttail): Add. * tree-cfg.cc (notice_special_calls): Record has_musttail. (clear_special_calls): Clear has_musttail. * tree-pass.h (make_pass_musttail): Add. * tree-tailcall.cc (find_tail_calls): Handle only_musttail argument. (tree_optimize_tail_calls_1): Pass on only_musttail. (execute_tail_calls): Pass only_musttail as false. (class pass_musttail): Add. (make_pass_musttail): Add. --- gcc/tree-pass.h | 1 + 1 file changed, 1 insertion(+) (limited to 'gcc/tree-pass.h') diff --git a/gcc/tree-pass.h b/gcc/tree-pass.h index 84bc91b..3a0cf13 100644 --- a/gcc/tree-pass.h +++ b/gcc/tree-pass.h @@ -368,6 +368,7 @@ extern gimple_opt_pass *make_pass_sra (gcc::context *ctxt); extern gimple_opt_pass *make_pass_sra_early (gcc::context *ctxt); extern gimple_opt_pass *make_pass_tail_recursion (gcc::context *ctxt); extern gimple_opt_pass *make_pass_tail_calls (gcc::context *ctxt); +extern gimple_opt_pass *make_pass_musttail (gcc::context *ctxt); extern gimple_opt_pass *make_pass_fix_loops (gcc::context *ctxt); extern gimple_opt_pass *make_pass_tree_loop (gcc::context *ctxt); extern gimple_opt_pass *make_pass_tree_no_loop (gcc::context *ctxt); -- cgit v1.1