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| author | Richard Biener <rguenther@suse.de> | 2023-11-30 12:38:53 +0100 |
|---|---|---|
| committer | Richard Biener <rguenther@suse.de> | 2023-11-30 13:31:26 +0100 |
| commit | 2dde9f326ded84814a78c3044294b535c1f97b41 (patch) | |
| tree | 2c046a11b555c269b6aaa78c21693da4ba8761cc | |
| parent | 8a6062a47b33da6d961c6354fd5788bc46aef0a9 (diff) | |
| download | gcc-2dde9f326ded84814a78c3044294b535c1f97b41.zip gcc-2dde9f326ded84814a78c3044294b535c1f97b41.tar.gz gcc-2dde9f326ded84814a78c3044294b535c1f97b41.tar.bz2 | |
tree-optimization/112767 - spurious diagnostic after sccp/loop-split swap
We are diagnosing an unreachable loop which we only manage to elide
after the copyprop pass after sccp which leaves the code open for
diagnosing by the intermittent ivcanon pass. The following makes sure
to clean things up a bit earlier, propagating constant final values
to uses immediately.
PR tree-optimization/112767
* tree-scalar-evolution.cc (final_value_replacement_loop):
Propagate constants to immediate uses immediately.
* gcc.dg/tree-ssa/pr112767.c: New testcase.
* gcc.dg/graphite/pr83255.c: Disable SCCP.
| -rw-r--r-- | gcc/testsuite/gcc.dg/graphite/pr83255.c | 2 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.dg/tree-ssa/pr112767.c | 18 | ||||
| -rw-r--r-- | gcc/tree-scalar-evolution.cc | 11 |
3 files changed, 29 insertions, 2 deletions
diff --git a/gcc/testsuite/gcc.dg/graphite/pr83255.c b/gcc/testsuite/gcc.dg/graphite/pr83255.c index cb376fa..0753263 100644 --- a/gcc/testsuite/gcc.dg/graphite/pr83255.c +++ b/gcc/testsuite/gcc.dg/graphite/pr83255.c @@ -1,5 +1,5 @@ /* { dg-do run } */ -/* { dg-options "-O -floop-nest-optimize -fdump-tree-graphite-details" } */ +/* { dg-options "-O -floop-nest-optimize -fno-tree-scev-cprop -fdump-tree-graphite-details" } */ int rx, in; diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr112767.c b/gcc/testsuite/gcc.dg/tree-ssa/pr112767.c new file mode 100644 index 0000000..3f9bc06 --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/pr112767.c @@ -0,0 +1,18 @@ +/* { dg-do compile } */ +/* { dg-options "-O3" } */ + +double reg_dict[32]; + +void foo(int); + +void initialize() +{ + int i=8; + for (int phi=0; phi<8; ++phi) { + reg_dict[i]=0; /* { dg-bogus "undefined behavior" } */ + int sn = 0; + if (i < 16) sn = 20; + foo(sn); + ++i; + } +} diff --git a/gcc/tree-scalar-evolution.cc b/gcc/tree-scalar-evolution.cc index f61277c..065bcd0 100644 --- a/gcc/tree-scalar-evolution.cc +++ b/gcc/tree-scalar-evolution.cc @@ -3841,11 +3841,20 @@ final_value_replacement_loop (class loop *loop) print_gimple_stmt (dump_file, phi, 0); fprintf (dump_file, " with expr: "); print_generic_expr (dump_file, def); + fprintf (dump_file, "\n"); } any = true; def = unshare_expr (def); remove_phi_node (&psi, false); + /* Propagate constants immediately. */ + if (CONSTANT_CLASS_P (def)) + { + replace_uses_by (rslt, def); + release_ssa_name (rslt); + continue; + } + /* Create the replacement statements. */ gimple_seq stmts; def = force_gimple_operand (def, &stmts, false, NULL_TREE); @@ -3877,7 +3886,7 @@ final_value_replacement_loop (class loop *loop) gsi_insert_seq_before (&gsi, stmts, GSI_SAME_STMT); if (dump_file) { - fprintf (dump_file, "\n final stmt:\n "); + fprintf (dump_file, " final stmt:\n "); print_gimple_stmt (dump_file, SSA_NAME_DEF_STMT (rslt), 0); fprintf (dump_file, "\n"); } |