From f4a6516dbf1c97af3c36c097b2de83f2310c9701 Mon Sep 17 00:00:00 2001 From: pinskia Date: Fri, 25 Nov 2005 04:54:59 +0000 Subject: [PATCH] 2005-11-25 Andrew Pinski PR middle-end/24990 * fold-const.c (fold_binary): Fold (~a) == C to a == ~C for C being INTEGER_CST. Likewise for !=. 2005-11-24 Andrew Pinski PR middle-end/24990 * tree-ssa/pr24990-1.c: New test. git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@107487 138bc75d-0d04-0410-961f-82ee72b054a4 --- gcc/ChangeLog | 6 ++++++ gcc/fold-const.c | 7 +++++++ gcc/testsuite/ChangeLog | 5 +++++ gcc/testsuite/gcc.dg/tree-ssa/pr24990-1.c | 21 +++++++++++++++++++++ 4 files changed, 39 insertions(+) create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/pr24990-1.c diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 2d5eed2dd1d..aeb45fdd654 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2005-11-25 Andrew Pinski + + PR middle-end/24990 + * fold-const.c (fold_binary): Fold (~a) == C to a == ~C + for C being INTEGER_CST. Likewise for !=. + 2005-11-25 Joseph S. Myers PR middle-end/24998 diff --git a/gcc/fold-const.c b/gcc/fold-const.c index 2d750f6c94c..962ebd3c395 100644 --- a/gcc/fold-const.c +++ b/gcc/fold-const.c @@ -8839,6 +8839,13 @@ fold_binary (enum tree_code code, tree type, tree op0, tree op1) /* If one arg is a real or integer constant, put it last. */ if (tree_swap_operands_p (arg0, arg1, true)) return fold_build2 (swap_tree_comparison (code), type, op1, op0); + + /* ~a != C becomes a != ~C where C is a constant. Likewise for ==. */ + if (TREE_CODE (arg0) == BIT_NOT_EXPR && TREE_CODE (arg1) == INTEGER_CST + && (code == NE_EXPR || code == EQ_EXPR)) + return fold_build2 (code, type, TREE_OPERAND (arg0, 0), + fold_build1 (BIT_NOT_EXPR, TREE_TYPE (arg1), + arg1)); /* bool_var != 0 becomes bool_var. */ if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_zerop (arg1) diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index d2bc9934637..cb611dc1edc 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2005-11-24 Andrew Pinski + + PR middle-end/24990 + * tree-ssa/pr24990-1.c: New test. + 2005-11-24 Richard Guenther Dirk Mueller diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr24990-1.c b/gcc/testsuite/gcc.dg/tree-ssa/pr24990-1.c new file mode 100644 index 00000000000..a518df025f6 --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/pr24990-1.c @@ -0,0 +1,21 @@ +/* { dg-do compile } */ +/* { dg-options "-O1 -fdump-tree-optimized" } */ + +int f(int x) +{ + return ((~x) != 0); +} +int f1(int x) +{ + return ((~x) == 0); +} + +/* There should be no != 0 which is produced by the front-end as + ~x != 0 is the same as x != -1 (or ~0). Likewise for ==. */ +/* { dg-final { scan-tree-dump-times "!= 0" 0 "optimized"} } */ +/* { dg-final { scan-tree-dump-times "!= -1" 1 "optimized"} } */ +/* { dg-final { scan-tree-dump-times "== 0" 0 "optimized"} } */ +/* { dg-final { scan-tree-dump-times "== -1" 1 "optimized"} } */ + +/* { dg-final { cleanup-tree-dump "optimized" } } */ + -- 2.11.0