diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 4fccde3b980..224e1a551b8 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,12 @@ +2011-09-07 Richard Guenther + + PR tree-optimization/50213 + * tree-flow.h (simple_iv_increment_p): Declare. + * tree-ssa-dom.c (simple_iv_increment_p): Export. Also handle + POINTER_PLUS_EXPR. + * tree-ssa-forwprop.c (ssa_forward_propagate_and_combine): Do + not propagate simple IV counter increments. + 2011-09-07 Eric Botcazou Iain Sandoe diff --git a/gcc/tree-flow.h b/gcc/tree-flow.h index 28c0d8aabbc..d4bf54cbe69 100644 --- a/gcc/tree-flow.h +++ b/gcc/tree-flow.h @@ -597,6 +597,7 @@ extern void dump_dominator_optimization_stats (FILE *); extern void debug_dominator_optimization_stats (void); int loop_depth_of_name (tree); tree degenerate_phi_result (gimple); +bool simple_iv_increment_p (gimple); /* In tree-ssa-copy.c */ extern void propagate_value (use_operand_p, tree); diff --git a/gcc/tree-ssa-dom.c b/gcc/tree-ssa-dom.c index 7a00c8ad937..18923aede7b 100644 --- a/gcc/tree-ssa-dom.c +++ b/gcc/tree-ssa-dom.c @@ -1409,9 +1409,10 @@ record_equality (tree x, tree y) i_1 = phi (..., i_2) i_2 = i_1 +/- ... */ -static bool +bool simple_iv_increment_p (gimple stmt) { + enum tree_code code; tree lhs, preinc; gimple phi; size_t i; @@ -1423,12 +1424,13 @@ simple_iv_increment_p (gimple stmt) if (TREE_CODE (lhs) != SSA_NAME) return false; - if (gimple_assign_rhs_code (stmt) != PLUS_EXPR - && gimple_assign_rhs_code (stmt) != MINUS_EXPR) + code = gimple_assign_rhs_code (stmt); + if (code != PLUS_EXPR + && code != MINUS_EXPR + && code != POINTER_PLUS_EXPR) return false; preinc = gimple_assign_rhs1 (stmt); - if (TREE_CODE (preinc) != SSA_NAME) return false; diff --git a/gcc/tree-ssa-forwprop.c b/gcc/tree-ssa-forwprop.c index 89d6239836b..ae37095d88e 100644 --- a/gcc/tree-ssa-forwprop.c +++ b/gcc/tree-ssa-forwprop.c @@ -2377,21 +2377,23 @@ ssa_forward_propagate_and_combine (void) else gsi_next (&gsi); } - else if (code == POINTER_PLUS_EXPR && can_propagate_from (stmt)) + else if (code == POINTER_PLUS_EXPR) { - if (TREE_CODE (gimple_assign_rhs2 (stmt)) == INTEGER_CST + tree off = gimple_assign_rhs2 (stmt); + if (TREE_CODE (off) == INTEGER_CST + && can_propagate_from (stmt) + && !simple_iv_increment_p (stmt) /* ??? Better adjust the interface to that function instead of building new trees here. */ && forward_propagate_addr_expr - (lhs, - build1 (ADDR_EXPR, - TREE_TYPE (rhs), - fold_build2 (MEM_REF, - TREE_TYPE (TREE_TYPE (rhs)), - rhs, - fold_convert - (ptr_type_node, - gimple_assign_rhs2 (stmt)))))) + (lhs, + build1_loc (gimple_location (stmt), + ADDR_EXPR, TREE_TYPE (rhs), + fold_build2 (MEM_REF, + TREE_TYPE (TREE_TYPE (rhs)), + rhs, + fold_convert (ptr_type_node, + off))))) { release_defs (stmt); todoflags |= TODO_remove_unused_locals;