Some cleanups before I touch this code. Bootstrapped and tested on x86_64-unknown-linux-gnu, applied to trunk.
Richard. 2011-09-06 Richard Guenther <rguent...@suse.de> * tree-ssa-sccvn.c (visit_use): CSE stmt pieces and simplify matching. Index: gcc/tree-ssa-sccvn.c =================================================================== --- gcc/tree-ssa-sccvn.c (revision 178570) +++ gcc/tree-ssa-sccvn.c (working copy) @@ -3043,16 +3043,17 @@ visit_use (tree use) changed = defs_to_varying (stmt); else if (is_gimple_assign (stmt)) { + enum tree_code code = gimple_assign_rhs_code (stmt); tree lhs = gimple_assign_lhs (stmt); + tree rhs1 = gimple_assign_rhs1 (stmt); tree simplified; /* Shortcut for copies. Simplifying copies is pointless, since we copy the expression and value they represent. */ - if (gimple_assign_copy_p (stmt) - && TREE_CODE (gimple_assign_rhs1 (stmt)) == SSA_NAME + if (code == SSA_NAME && TREE_CODE (lhs) == SSA_NAME) { - changed = visit_copy (lhs, gimple_assign_rhs1 (stmt)); + changed = visit_copy (lhs, rhs1); goto done; } simplified = try_to_simplify (stmt); @@ -3119,24 +3120,22 @@ visit_use (tree use) /* We can substitute SSA_NAMEs that are live over abnormal edges with their constant value. */ && !(gimple_assign_copy_p (stmt) - && is_gimple_min_invariant (gimple_assign_rhs1 (stmt))) + && is_gimple_min_invariant (rhs1)) && !(simplified && is_gimple_min_invariant (simplified)) && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (lhs)) /* Stores or copies from SSA_NAMEs that are live over abnormal edges are a problem. */ - || (gimple_assign_single_p (stmt) - && TREE_CODE (gimple_assign_rhs1 (stmt)) == SSA_NAME - && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (gimple_assign_rhs1 (stmt)))) + || (code == SSA_NAME + && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (rhs1))) changed = defs_to_varying (stmt); - else if (REFERENCE_CLASS_P (lhs) || DECL_P (lhs)) - { - changed = visit_reference_op_store (lhs, gimple_assign_rhs1 (stmt), stmt); - } + else if (REFERENCE_CLASS_P (lhs) + || DECL_P (lhs)) + changed = visit_reference_op_store (lhs, rhs1, stmt); else if (TREE_CODE (lhs) == SSA_NAME) { if ((gimple_assign_copy_p (stmt) - && is_gimple_min_invariant (gimple_assign_rhs1 (stmt))) + && is_gimple_min_invariant (rhs1)) || (simplified && is_gimple_min_invariant (simplified))) { @@ -3144,11 +3143,11 @@ visit_use (tree use) if (simplified) changed = set_ssa_val_to (lhs, simplified); else - changed = set_ssa_val_to (lhs, gimple_assign_rhs1 (stmt)); + changed = set_ssa_val_to (lhs, rhs1); } else { - switch (get_gimple_rhs_class (gimple_assign_rhs_code (stmt))) + switch (get_gimple_rhs_class (code)) { case GIMPLE_UNARY_RHS: case GIMPLE_BINARY_RHS: @@ -3156,25 +3155,24 @@ visit_use (tree use) changed = visit_nary_op (lhs, stmt); break; case GIMPLE_SINGLE_RHS: - switch (TREE_CODE_CLASS (gimple_assign_rhs_code (stmt))) + switch (TREE_CODE_CLASS (code)) { case tcc_reference: /* VOP-less references can go through unary case. */ - if ((gimple_assign_rhs_code (stmt) == REALPART_EXPR - || gimple_assign_rhs_code (stmt) == IMAGPART_EXPR - || gimple_assign_rhs_code (stmt) == VIEW_CONVERT_EXPR) - && TREE_CODE (TREE_OPERAND (gimple_assign_rhs1 (stmt), 0)) == SSA_NAME) + if ((code == REALPART_EXPR + || code == IMAGPART_EXPR + || code == VIEW_CONVERT_EXPR) + && TREE_CODE (TREE_OPERAND (rhs1, 0)) == SSA_NAME) { changed = visit_nary_op (lhs, stmt); break; } /* Fallthrough. */ case tcc_declaration: - changed = visit_reference_op_load - (lhs, gimple_assign_rhs1 (stmt), stmt); + changed = visit_reference_op_load (lhs, rhs1, stmt); break; case tcc_expression: - if (gimple_assign_rhs_code (stmt) == ADDR_EXPR) + if (code == ADDR_EXPR) { changed = visit_nary_op (lhs, stmt); break;