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| author | James A. Morrison <phython@gcc.gnu.org> | 2005-03-04 02:48:30 +0000 |
|---|---|---|
| committer | James A. Morrison <phython@gcc.gnu.org> | 2005-03-04 02:48:30 +0000 |
| commit | 8d06c80914d7374d16887b0e817eadb41d898aa8 (patch) | |
| tree | c908d67b93dc9a831686bb43afc3806aef6fd260 /gcc | |
| parent | 3159b178b0479e9c8998982c112f486d5d28ab53 (diff) | |
| download | gcc-8d06c80914d7374d16887b0e817eadb41d898aa8.zip gcc-8d06c80914d7374d16887b0e817eadb41d898aa8.tar.gz gcc-8d06c80914d7374d16887b0e817eadb41d898aa8.tar.bz2 | |
re PR tree-optimization/15784 (fold misses binary optimization)
2005-03-03 James A. Morrison <phython@gcc.gnu.org>
PR tree-optimization/15784
* fold-const.c (fold): Fold ~A + 1 to -1. Fold -A - 1
and -1 - A to ~A.
From-SVN: r95870
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 6 | ||||
| -rw-r--r-- | gcc/fold-const.c | 15 | ||||
| -rw-r--r-- | gcc/testsuite/ChangeLog | 4 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.dg/pr15784-4.c | 12 |
4 files changed, 37 insertions, 0 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 67c26a2..19b45f2 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2005-03-03 James A. Morrison <phython@gcc.gnu.org> + + PR tree-optimization/15784 + * fold-const.c (fold): Fold ~A + 1 to -1. Fold -A - 1 + and -1 - A to ~A. + 2005-03-03 David Edelsohn <edelsohn@gnu.org> * config/rs6000/predicates.md (branch_comparison_operator): diff --git a/gcc/fold-const.c b/gcc/fold-const.c index 72e557e..2c6d71e 100644 --- a/gcc/fold-const.c +++ b/gcc/fold-const.c @@ -7223,6 +7223,11 @@ fold (tree expr) if (TREE_CODE (arg0) == NEGATE_EXPR && reorder_operands_p (TREE_OPERAND (arg0, 0), arg1)) return fold (build2 (MINUS_EXPR, type, arg1, TREE_OPERAND (arg0, 0))); + /* Convert ~A + 1 to -A. */ + if (INTEGRAL_TYPE_P (type) + && TREE_CODE (arg0) == BIT_NOT_EXPR + && integer_onep (arg1)) + return fold (build1 (NEGATE_EXPR, type, TREE_OPERAND (arg0, 0))); if (TREE_CODE (type) == COMPLEX_TYPE) { @@ -7661,6 +7666,16 @@ fold (tree expr) && reorder_operands_p (arg0, arg1)) return fold (build2 (MINUS_EXPR, type, negate_expr (arg1), TREE_OPERAND (arg0, 0))); + /* Convert -A - 1 to ~A. */ + if (INTEGRAL_TYPE_P (type) + && TREE_CODE (arg0) == NEGATE_EXPR + && integer_onep (arg1)) + return fold (build1 (BIT_NOT_EXPR, type, TREE_OPERAND (arg0, 0))); + + /* Convert -1 - A to ~A. */ + if (INTEGRAL_TYPE_P (type) + && integer_all_onesp (arg0)) + return fold (build1 (BIT_NOT_EXPR, type, arg1)); if (TREE_CODE (type) == COMPLEX_TYPE) { diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index e589f7b..b7a3692 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,7 @@ +2005-03-03 James A. Morrison <phython@gcc.gnu.org> + + * gcc.dg/pr15784-4.c: New test. + 2005-03-03 Geoffrey Keating <geoffk@apple.com> * gcc.c-torture/execute/pr17133.c: New. diff --git a/gcc/testsuite/gcc.dg/pr15784-4.c b/gcc/testsuite/gcc.dg/pr15784-4.c new file mode 100644 index 0000000..021b637 --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr15784-4.c @@ -0,0 +1,12 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -fdump-tree-optimized" } */ +int a (int x) { + return ~x + 1; /* -x */ +} + +int b (int x) { + return -x -1; /* ~x */ +} + +/* { dg-final { scan-tree-dump "~x;" "optimized" } } */ +/* { dg-final { scan-tree-dump "-x;" "optimized" } } */ |