On Fri, Sep 30, 2011 at 10:57:25AM +0200, Richard Guenther wrote: > Definitely. Seeing a decl will enable better offset-based > disambiguation.
Ok, here is an updated patch. Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? 2011-09-30 Jakub Jelinek <ja...@redhat.com> * fold-const.c (fold_unary_loc): Don't optimize POINTER_PLUS_EXPR casted to TYPE_RESTRICT pointer by casting the inner pointer if it isn't TYPE_RESTRICT. * tree-ssa-forwprop.c (forward_propagate_addr_expr_1): Don't through casts from non-TYPE_RESTRICT pointer to TYPE_RESTRICT pointer. * gcc.dg/tree-ssa/restrict-4.c: New test. --- gcc/fold-const.c.jj 2011-09-29 14:25:46.000000000 +0200 +++ gcc/fold-const.c 2011-09-29 18:20:04.000000000 +0200 @@ -7929,6 +7929,7 @@ fold_unary_loc (location_t loc, enum tre that this happens when X or Y is NOP_EXPR or Y is INTEGER_CST. */ if (POINTER_TYPE_P (type) && TREE_CODE (arg0) == POINTER_PLUS_EXPR + && (!TYPE_RESTRICT (type) || TYPE_RESTRICT (TREE_TYPE (arg0))) && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST || TREE_CODE (TREE_OPERAND (arg0, 0)) == NOP_EXPR || TREE_CODE (TREE_OPERAND (arg0, 1)) == NOP_EXPR)) --- gcc/tree-ssa-forwprop.c.jj 2011-09-15 12:18:54.000000000 +0200 +++ gcc/tree-ssa-forwprop.c 2011-09-29 19:08:03.000000000 +0200 @@ -804,6 +804,11 @@ forward_propagate_addr_expr_1 (tree name && ((rhs_code == SSA_NAME && rhs == name) || CONVERT_EXPR_CODE_P (rhs_code))) { + /* Don't propagate restrict pointer's RHS. */ + if (TYPE_RESTRICT (TREE_TYPE (lhs)) + && !TYPE_RESTRICT (TREE_TYPE (name)) + && !is_gimple_min_invariant (def_rhs)) + return false; /* Only recurse if we don't deal with a single use or we cannot do the propagation to the current statement. In particular we can end up with a conversion needed for a non-invariant --- gcc/testsuite/gcc.dg/tree-ssa/restrict-4.c.jj 2011-09-29 20:21:00.000000000 +0200 +++ gcc/testsuite/gcc.dg/tree-ssa/restrict-4.c 2011-09-29 20:21:57.000000000 +0200 @@ -0,0 +1,26 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -fdump-tree-optimized" } */ + +int +foo (int *x, int y) +{ + int *__restrict p1 = x; + int *__restrict p2 = x + 32; + p1[y] = 1; + p2[4] = 2; + return p1[y]; +} + +int +bar (int *x, int y) +{ + int *__restrict p1 = x; + int *p3 = x + 32; + int *__restrict p2 = p3; + p1[y] = 1; + p2[4] = 2; + return p1[y]; +} + +/* { dg-final { scan-tree-dump-times "return 1;" 2 "optimized" } } */ +/* { dg-final { cleanup-tree-dump "optimized" } } */ Jakub