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| author | Andrew Pinski <pinskia@physics.uc.edu> | 2005-07-21 19:33:45 +0000 |
|---|---|---|
| committer | Andrew Pinski <pinskia@gcc.gnu.org> | 2005-07-21 12:33:45 -0700 |
| commit | 9d24eb542cfde81c37ad94029f3d51375785b251 (patch) | |
| tree | f83d95ac14a5aafcb09fd2420e89f60afb9ba7b4 /gcc/fold-const.c | |
| parent | 35f5a23f7bc7c0a21bbaf8a0ca8c4be551b99c88 (diff) | |
| download | gcc-9d24eb542cfde81c37ad94029f3d51375785b251.zip gcc-9d24eb542cfde81c37ad94029f3d51375785b251.tar.gz gcc-9d24eb542cfde81c37ad94029f3d51375785b251.tar.bz2 | |
re PR tree-optimization/19055 (Minor bit optimization with or and xor)
2005-07-21 Andrew Pinski <pinskia@physics.uc.edu>
PR middle-end/19055
* gcc.dg/tree-ssa/pr19055.c: New test.
* gcc.dg/tree-ssa/pr19055-2.c: New test.
2005-07-21 Andrew Pinski <pinskia@physics.uc.edu>
PR middle-end/19055
* fold-const.c (fold_binary): Transform "(X | Y) ^ X" to "Y & ~ X".
From-SVN: r102243
Diffstat (limited to 'gcc/fold-const.c')
| -rw-r--r-- | gcc/fold-const.c | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/gcc/fold-const.c b/gcc/fold-const.c index 7b83eb3..acafd6a 100644 --- a/gcc/fold-const.c +++ b/gcc/fold-const.c @@ -8059,6 +8059,54 @@ fold_binary (enum tree_code code, tree type, tree op0, tree op1) goto bit_ior; } + /* (X | Y) ^ X -> Y & ~ X*/ + if (TREE_CODE (arg0) == BIT_IOR_EXPR + && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)) + { + tree t2 = TREE_OPERAND (arg0, 1); + t1 = fold_build1 (BIT_NOT_EXPR, TREE_TYPE (arg1), + arg1); + t1 = fold_build2 (BIT_AND_EXPR, type, fold_convert (type, t2), + fold_convert (type, t1)); + return t1; + } + + /* (Y | X) ^ X -> Y & ~ X*/ + if (TREE_CODE (arg0) == BIT_IOR_EXPR + && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0)) + { + tree t2 = TREE_OPERAND (arg0, 0); + t1 = fold_build1 (BIT_NOT_EXPR, TREE_TYPE (arg1), + arg1); + t1 = fold_build2 (BIT_AND_EXPR, type, fold_convert (type, t2), + fold_convert (type, t1)); + return t1; + } + + /* X ^ (X | Y) -> Y & ~ X*/ + if (TREE_CODE (arg1) == BIT_IOR_EXPR + && operand_equal_p (TREE_OPERAND (arg1, 0), arg0, 0)) + { + tree t2 = TREE_OPERAND (arg1, 1); + t1 = fold_build1 (BIT_NOT_EXPR, TREE_TYPE (arg0), + arg0); + t1 = fold_build2 (BIT_AND_EXPR, type, fold_convert (type, t2), + fold_convert (type, t1)); + return t1; + } + + /* X ^ (Y | X) -> Y & ~ X*/ + if (TREE_CODE (arg1) == BIT_IOR_EXPR + && operand_equal_p (TREE_OPERAND (arg1, 1), arg0, 0)) + { + tree t2 = TREE_OPERAND (arg1, 0); + t1 = fold_build1 (BIT_NOT_EXPR, TREE_TYPE (arg0), + arg0); + t1 = fold_build2 (BIT_AND_EXPR, type, fold_convert (type, t2), + fold_convert (type, t1)); + return t1; + } + /* Convert ~X ^ ~Y to X ^ Y. */ if (TREE_CODE (arg0) == BIT_NOT_EXPR && TREE_CODE (arg1) == BIT_NOT_EXPR) |