public inbox for gcc-cvs@sourceware.org help / color / mirror / Atom feed
From: Richard Biener <rguenth@gcc.gnu.org> To: gcc-cvs@gcc.gnu.org Subject: [gcc r14-9064] rtl-optimization/54052 - RTL SSA PHI insertion compile-time hog Date: Mon, 19 Feb 2024 13:42:30 +0000 (GMT) [thread overview] Message-ID: <20240219134230.913E93864877@sourceware.org> (raw) https://gcc.gnu.org/g:c7151283dc747769d4ac4f216d8f519bda2569b5 commit r14-9064-gc7151283dc747769d4ac4f216d8f519bda2569b5 Author: Richard Biener <rguenther@suse.de> Date: Mon Feb 19 11:10:50 2024 +0100 rtl-optimization/54052 - RTL SSA PHI insertion compile-time hog The following tries to address the PHI insertion compile-time hog in RTL fwprop observed with the PR54052 testcase where the loop computing the "unfiltered" set of variables possibly needing PHI nodes for each block exhibits quadratic compile-time and memory-use. It does so by pruning the local DEFs with LR_OUT of the block, removing regs that can never be LR_IN (defined by this block) in the dominance frontier. PR rtl-optimization/54052 * rtl-ssa/blocks.cc (function_info::place_phis): Filter local defs by LR_OUT. Diff: --- gcc/rtl-ssa/blocks.cc | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/gcc/rtl-ssa/blocks.cc b/gcc/rtl-ssa/blocks.cc index 8996443e8d5a..cf4224e61ecf 100644 --- a/gcc/rtl-ssa/blocks.cc +++ b/gcc/rtl-ssa/blocks.cc @@ -645,7 +645,12 @@ function_info::place_phis (build_info &bi) if (bitmap_empty_p (&frontiers[b1])) continue; - bitmap b1_def = &DF_LR_BB_INFO (BASIC_BLOCK_FOR_FN (m_fn, b1))->def; + // Defs in B1 that are possibly in LR_IN in the dominance frontier + // blocks. + auto_bitmap b1_def; + bitmap_and (b1_def, &DF_LR_BB_INFO (BASIC_BLOCK_FOR_FN (m_fn, b1))->def, + DF_LR_OUT (BASIC_BLOCK_FOR_FN (m_fn, b1))); + bitmap_iterator bmi; unsigned int b2; EXECUTE_IF_SET_IN_BITMAP (&frontiers[b1], 0, b2, bmi)
reply other threads:[~2024-02-19 13:42 UTC|newest] Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20240219134230.913E93864877@sourceware.org \ --to=rguenth@gcc.gnu.org \ --cc=gcc-cvs@gcc.gnu.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).