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| author | Richard Biener <rguenther@suse.de> | 2024-02-19 11:10:50 +0100 |
|---|---|---|
| committer | Richard Biener <rguenther@suse.de> | 2024-02-19 14:42:15 +0100 |
| commit | c7151283dc747769d4ac4f216d8f519bda2569b5 (patch) | |
| tree | bc1be2c5694aab289d2af271362301a8b6a79c60 | |
| parent | 78b72ee5a80f45bd761a55006e2b3fc2cbe749bc (diff) | |
| download | gcc-c7151283dc747769d4ac4f216d8f519bda2569b5.zip gcc-c7151283dc747769d4ac4f216d8f519bda2569b5.tar.gz gcc-c7151283dc747769d4ac4f216d8f519bda2569b5.tar.bz2 | |
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.
| -rw-r--r-- | gcc/rtl-ssa/blocks.cc | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/gcc/rtl-ssa/blocks.cc b/gcc/rtl-ssa/blocks.cc index 8996443..cf4224e 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) |