diff options
| author | krebbel <krebbel@138bc75d-0d04-0410-961f-82ee72b054a4> | 2019-09-20 09:23:50 +0000 |
|---|---|---|
| committer | krebbel <krebbel@138bc75d-0d04-0410-961f-82ee72b054a4> | 2019-09-20 09:23:50 +0000 |
| commit | 08f8d17daed89c9b9b0802fece6f5eb42b2bba28 (patch) | |
| tree | 131210a739ae8f5614116994794d072e2fe3f4fc | |
| parent | ae21909faf644ba583f3f950e45a115733744292 (diff) | |
Fix PR88751
This patch implements a small improvement for the heuristic in lra
which decides when it has to activate the simpler register allocation
algorithm.
gcc/ChangeLog:
2019-09-20 Andreas Krebbel <krebbel@linux.ibm.com>
Backport from mainline
2019-06-06 Andreas Krebbel <krebbel@linux.ibm.com>
PR rtl-optimization/88751
* ira.c (ira): Use the number of the actually referenced registers
when calculating the threshold.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/branches/gcc-7-branch@275993 138bc75d-0d04-0410-961f-82ee72b054a4
| -rw-r--r-- | gcc/ChangeLog | 9 | ||||
| -rw-r--r-- | gcc/ira.c | 9 |
2 files changed, 17 insertions, 1 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index ad4384a37c3..533ab1c3f13 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,12 @@ +2019-09-20 Andreas Krebbel <krebbel@linux.ibm.com> + + Backport from mainline + 2019-06-06 Andreas Krebbel <krebbel@linux.ibm.com> + + PR rtl-optimization/88751 + * ira.c (ira): Use the number of the actually referenced registers + when calculating the threshold. + 2019-09-11 Eric Botcazou <ebotcazou@adacore.com> PR rtl-optimization/89795 diff --git a/gcc/ira.c b/gcc/ira.c index 5265ab17488..4925cc713b0 100644 --- a/gcc/ira.c +++ b/gcc/ira.c @@ -5160,6 +5160,8 @@ ira (FILE *f) int ira_max_point_before_emit; bool saved_flag_caller_saves = flag_caller_saves; enum ira_region saved_flag_ira_region = flag_ira_region; + unsigned int i; + int num_used_regs = 0; clear_bb_flags (); @@ -5175,12 +5177,17 @@ ira (FILE *f) ira_conflicts_p = optimize > 0; + /* Determine the number of pseudos actually requiring coloring. */ + for (i = FIRST_PSEUDO_REGISTER; i < DF_REG_SIZE (df); i++) + num_used_regs += !!(DF_REG_USE_COUNT (i) + DF_REG_DEF_COUNT (i)); + /* If there are too many pseudos and/or basic blocks (e.g. 10K pseudos and 10K blocks or 100K pseudos and 1K blocks), we will use simplified and faster algorithms in LRA. */ lra_simple_p = (ira_use_lra_p - && max_reg_num () >= (1 << 26) / last_basic_block_for_fn (cfun)); + && num_used_regs >= (1 << 26) / last_basic_block_for_fn (cfun)); + if (lra_simple_p) { /* It permits to skip live range splitting in LRA. */ |