From c91fedc5ff51bf5b152892060f29a6df8a8bb2af Mon Sep 17 00:00:00 2001 From: rguenth Date: Thu, 5 Jan 2012 13:41:34 +0000 Subject: 2012-01-05 Richard Guenther PR tree-optimization/51760 * tree-ssa-ccp.c (likely_value): Drop UNDEFINED to CONSTANT, not VARYING. (bit_value_unop): Handle UNDEFINED operands. (bit_value_binop): Likewise. * gcc.dg/torture/pr51760.c: New testcase. git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@182909 138bc75d-0d04-0410-961f-82ee72b054a4 --- gcc/tree-ssa-ccp.c | 19 +++++++++++++++++-- 1 file changed, 17 insertions(+), 2 deletions(-) (limited to 'gcc/tree-ssa-ccp.c') diff --git a/gcc/tree-ssa-ccp.c b/gcc/tree-ssa-ccp.c index 738606fad02..2080c06cce6 100644 --- a/gcc/tree-ssa-ccp.c +++ b/gcc/tree-ssa-ccp.c @@ -657,9 +657,10 @@ likely_value (gimple stmt) } } /* If there was an UNDEFINED operand but the result may be not UNDEFINED - fall back to VARYING even if there were CONSTANT operands. */ + fall back to CONSTANT. During iteration UNDEFINED may still drop + to CONSTANT. */ if (has_undefined_operand) - return VARYING; + return CONSTANT; /* We do not consider virtual operands here -- load from read-only memory may have only VARYING virtual operands, but still be @@ -1368,6 +1369,10 @@ bit_value_unop (enum tree_code code, tree type, tree rhs) prop_value_t rval = get_value_for_expr (rhs, true); double_int value, mask; prop_value_t val; + + if (rval.lattice_val == UNDEFINED) + return rval; + gcc_assert ((rval.lattice_val == CONSTANT && TREE_CODE (rval.value) == INTEGER_CST) || double_int_minus_one_p (rval.mask)); @@ -1399,6 +1404,16 @@ bit_value_binop (enum tree_code code, tree type, tree rhs1, tree rhs2) prop_value_t r2val = get_value_for_expr (rhs2, true); double_int value, mask; prop_value_t val; + + if (r1val.lattice_val == UNDEFINED + || r2val.lattice_val == UNDEFINED) + { + val.lattice_val = VARYING; + val.value = NULL_TREE; + val.mask = double_int_minus_one; + return val; + } + gcc_assert ((r1val.lattice_val == CONSTANT && TREE_CODE (r1val.value) == INTEGER_CST) || double_int_minus_one_p (r1val.mask)); -- cgit v1.2.1