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| author | Jakub Jelinek <jakub@redhat.com> | 2020-01-07 11:05:14 +0100 |
|---|---|---|
| committer | Jakub Jelinek <jakub@gcc.gnu.org> | 2020-01-07 11:05:14 +0100 |
| commit | fb862fdfb53ecb189f8bd74b66de573a78045916 (patch) | |
| tree | 733c1ab99c29a45d7184f0131b1ae75029058b62 | |
| parent | f26916c2acdda19e36e57fff97b296897ebcba76 (diff) | |
| download | gcc-fb862fdfb53ecb189f8bd74b66de573a78045916.zip gcc-fb862fdfb53ecb189f8bd74b66de573a78045916.tar.gz gcc-fb862fdfb53ecb189f8bd74b66de573a78045916.tar.bz2 | |
re PR tree-optimization/93156 (abused nonnull attribute evokes new segfault in gcc 10 since Nov 4 commit, 0fb958ab8aa)
PR tree-optimization/93156
* tree-ssa-ccp.c (bit_value_binop): For x * x note that the second
least significant bit is always clear.
* gcc.dg/tree-ssa/pr93156.c: New test.
From-SVN: r279951
| -rw-r--r-- | gcc/ChangeLog | 6 | ||||
| -rw-r--r-- | gcc/testsuite/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.dg/tree-ssa/pr93156.c | 23 | ||||
| -rw-r--r-- | gcc/tree-ssa-ccp.c | 11 |
4 files changed, 43 insertions, 2 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index f90dc08..0ead18a 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,4 +1,8 @@ -2019-01-07 Jakub Jelinek <jakub@redhat.com> +2020-01-07 Jakub Jelinek <jakub@redhat.com> + + PR tree-optimization/93156 + * tree-ssa-ccp.c (bit_value_binop): For x * x note that the second + least significant bit is always clear. PR tree-optimization/93118 * match.pd ((x >> c) << c -> x & (-1<<c)): Add nop_convert?. Add new diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 403bc8a..b5c4bc0 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,4 +1,7 @@ -2019-01-07 Jakub Jelinek <jakub@redhat.com> +2020-01-07 Jakub Jelinek <jakub@redhat.com> + + PR tree-optimization/93156 + * gcc.dg/tree-ssa/pr93156.c: New test. PR tree-optimization/93118 * gcc.dg/tree-ssa/pr93118.c: New test. diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr93156.c b/gcc/testsuite/gcc.dg/tree-ssa/pr93156.c new file mode 100644 index 0000000..b8c2af3 --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/pr93156.c @@ -0,0 +1,23 @@ +/* PR tree-optimization/93156 */ +/* { dg-do compile } */ +/* { dg-options "-O2 -fdump-tree-optimized" } */ +/* { dg-final { scan-tree-dump-times "return 0;" 3 "optimized" } } */ + +int +foo (int x) +{ + return (x * x) & 2; +} + +unsigned long long +bar (unsigned long long x) +{ + return (x * x) & 2; +} + +int +baz (int x) +{ + x &= -2; + return (x * x) & 3; +} diff --git a/gcc/tree-ssa-ccp.c b/gcc/tree-ssa-ccp.c index add3d3f..be6647d 100644 --- a/gcc/tree-ssa-ccp.c +++ b/gcc/tree-ssa-ccp.c @@ -1650,6 +1650,17 @@ bit_value_binop (enum tree_code code, tree type, tree rhs1, tree rhs2) TYPE_SIGN (TREE_TYPE (rhs2)), TYPE_PRECISION (TREE_TYPE (rhs2)), value_to_wide_int (r2val), r2val.mask); + /* (x * x) & 2 == 0. */ + if (code == MULT_EXPR && rhs1 == rhs2 && TYPE_PRECISION (type) > 1) + { + widest_int m = 2; + if (wi::sext (mask, TYPE_PRECISION (type)) != -1) + value = wi::bit_and_not (value, m); + else + value = 0; + mask = wi::bit_and_not (mask, m); + } + if (wi::sext (mask, TYPE_PRECISION (type)) != -1) { val.lattice_val = CONSTANT; |