diff options
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 40 | ||||
| -rw-r--r-- | gcc/gimplify.c | 81 | ||||
| -rw-r--r-- | gcc/integrate.c | 1 | ||||
| -rw-r--r-- | gcc/tree-complex.c | 928 | ||||
| -rw-r--r-- | gcc/tree-gimple.c | 12 | ||||
| -rw-r--r-- | gcc/tree-optimize.c | 3 | ||||
| -rw-r--r-- | gcc/tree-pass.h | 1 | ||||
| -rw-r--r-- | gcc/tree.h | 13 |
8 files changed, 999 insertions, 80 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 2ae99ce3..672bb8f 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,43 @@ +2005-06-09 Richard Henderson <rth@redhat.com> + + PR tree-opt/20610 + * tree.h (DECL_COMPLEX_GIMPLE_REG_P): New. + (struct tree_decl): Add gimple_reg_flag. + * integrate.c (copy_decl_for_inlining): Copy it. + * gimplify.c (internal_get_tmp_var): Set it. + (gimplify_bind_expr): Likewise. + (gimplify_function_tree): Likewise. + (gimplify_modify_expr_complex_part): New. + (gimplify_modify_expr): Use it. + * tree-gimple.c (is_gimple_reg_type): Allow complex. + (is_gimple_reg): Allow complex with DECL_COMPLEX_GIMPLE_REG_P set. + + * tree-complex.c (complex_lattice_t): New. + (complex_lattice_values, complex_variable_components): New. + (some_nonzerop, find_lattice_value, is_complex_reg, + init_parameter_lattice_values, init_dont_simulate_again, + complex_visit_stmt, complex_visit_phi, create_components, + update_complex_components, update_parameter_components, + update_phi_components, update_all_vops, expand_complex_move): New. + (extract_component): Handle INDIRECT_REF, COMPONENT_REF, ARRAY_REF, + SSA_NAME. + (update_complex_assignment): Use update_complex_components; + handle updates of return_expr properly. + (expand_complex_addition): Use complex lattice values. + (expand_complex_multiplication): Likewise. + (expand_complex_division): Likewise. + (expand_complex_libcall): Use update_complex_components. + (expand_complex_comparison): Use update_stmt. + (expand_complex_operations_1): Use expand_complex_move, retrieve + lattice values. + (tree_lower_complex): Compute lattice values. + (tree_lower_complex_O0): Duplicate from tree_lower_complex. + (pass_lower_complex_O0): Rename from pass_lower_complex. + (pass_lower_complex, gate_no_optimization): New. + * tree-optimize.c (init_tree_optimization_passes): Update for + complex pass changes. + * tree-pass.h (pass_lower_complex_O0): Declare. + 2005-06-08 Dale Johannesen <dalej@apple.com> * config/darwin.c (darwin_binds_local_p): New. diff --git a/gcc/gimplify.c b/gcc/gimplify.c index bcc9ba2..df93bc5 100644 --- a/gcc/gimplify.c +++ b/gcc/gimplify.c @@ -470,6 +470,9 @@ internal_get_tmp_var (tree val, tree *pre_p, tree *post_p, bool is_formal) t = lookup_tmp_var (val, is_formal); + if (TREE_CODE (TREE_TYPE (t)) == COMPLEX_TYPE) + DECL_COMPLEX_GIMPLE_REG_P (t) = 1; + mod = build (MODIFY_EXPR, TREE_TYPE (t), t, val); if (EXPR_HAS_LOCATION (val)) @@ -856,7 +859,18 @@ gimplify_bind_expr (tree *expr_p, tree temp, tree *pre_p) /* Mark variables seen in this bind expr. */ for (t = BIND_EXPR_VARS (bind_expr); t ; t = TREE_CHAIN (t)) - DECL_SEEN_IN_BIND_EXPR_P (t) = 1; + { + DECL_SEEN_IN_BIND_EXPR_P (t) = 1; + + /* Preliminarily mark non-addressed complex variables as eligible + for promotion to gimple registers. We'll transform their uses + as we find them. */ + if (TREE_CODE (TREE_TYPE (t)) == COMPLEX_TYPE + && !TREE_THIS_VOLATILE (t) + && (TREE_CODE (t) == VAR_DECL && !DECL_HARD_REGISTER (t)) + && !needs_to_live_in_memory (t)) + DECL_COMPLEX_GIMPLE_REG_P (t) = 1; + } gimple_push_bind_expr (bind_expr); gimplify_ctxp->save_stack = false; @@ -3009,6 +3023,45 @@ gimplify_modify_expr_rhs (tree *expr_p, tree *from_p, tree *to_p, tree *pre_p, return ret; } +/* Promote partial stores to COMPLEX variables to total stores. *EXPR_P is + a MODIFY_EXPR with a lhs of a REAL/IMAGPART_EXPR of a variable with + DECL_COMPLEX_GIMPLE_REG_P set. */ + +static enum gimplify_status +gimplify_modify_expr_complex_part (tree *expr_p, tree *pre_p, bool want_value) +{ + enum tree_code code, ocode; + tree lhs, rhs, new_rhs, other, realpart, imagpart; + + lhs = TREE_OPERAND (*expr_p, 0); + rhs = TREE_OPERAND (*expr_p, 1); + code = TREE_CODE (lhs); + lhs = TREE_OPERAND (lhs, 0); + + ocode = code == REALPART_EXPR ? IMAGPART_EXPR : REALPART_EXPR; + other = build1 (ocode, TREE_TYPE (rhs), lhs); + other = get_formal_tmp_var (other, pre_p); + + realpart = code == REALPART_EXPR ? rhs : other; + imagpart = code == REALPART_EXPR ? other : rhs; + + if (TREE_CONSTANT (realpart) && TREE_CONSTANT (imagpart)) + new_rhs = build_complex (TREE_TYPE (lhs), realpart, imagpart); + else + new_rhs = build2 (COMPLEX_EXPR, TREE_TYPE (lhs), realpart, imagpart); + + TREE_OPERAND (*expr_p, 0) = lhs; + TREE_OPERAND (*expr_p, 1) = new_rhs; + + if (want_value) + { + append_to_statement_list (*expr_p, pre_p); + *expr_p = rhs; + } + + return GS_ALL_DONE; +} + /* Gimplify the MODIFY_EXPR node pointed by EXPR_P. modify_expr @@ -3084,6 +3137,14 @@ gimplify_modify_expr (tree *expr_p, tree *pre_p, tree *post_p, bool want_value) } } + /* Transform partial stores to non-addressable complex variables into + total stores. This allows us to use real instead of virtual operands + for these variables, which improves optimization. */ + if ((TREE_CODE (*to_p) == REALPART_EXPR + || TREE_CODE (*to_p) == IMAGPART_EXPR) + && is_gimple_reg (TREE_OPERAND (*to_p, 0))) + return gimplify_modify_expr_complex_part (expr_p, pre_p, want_value); + if (gimplify_ctxp->into_ssa && is_gimple_reg (*to_p)) { /* If we've somehow already got an SSA_NAME on the LHS, then @@ -4668,7 +4729,7 @@ gimplify_body (tree *body_p, tree fndecl, bool do_parms) void gimplify_function_tree (tree fndecl) { - tree oldfn; + tree oldfn, parm, ret; oldfn = current_function_decl; current_function_decl = fndecl; @@ -4676,6 +4737,22 @@ gimplify_function_tree (tree fndecl) if (cfun == NULL) allocate_struct_function (fndecl); + for (parm = DECL_ARGUMENTS (fndecl); parm ; parm = TREE_CHAIN (parm)) + { + /* Preliminarily mark non-addressed complex variables as eligible + for promotion to gimple registers. We'll transform their uses + as we find them. */ + if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE + && !TREE_THIS_VOLATILE (parm) + && !needs_to_live_in_memory (parm)) + DECL_COMPLEX_GIMPLE_REG_P (parm) = 1; + } + + ret = DECL_RESULT (fndecl); + if (TREE_CODE (TREE_TYPE (ret)) == COMPLEX_TYPE + && !needs_to_live_in_memory (ret)) + DECL_COMPLEX_GIMPLE_REG_P (ret) = 1; + gimplify_body (&DECL_SAVED_TREE (fndecl), fndecl, true); /* If we're instrumenting function entry/exit, then prepend the call to diff --git a/gcc/integrate.c b/gcc/integrate.c index 0f5cfcf..e6e0867 100644 --- a/gcc/integrate.c +++ b/gcc/integrate.c @@ -107,6 +107,7 @@ copy_decl_for_inlining (tree decl, tree from_fn, tree to_fn) TREE_ADDRESSABLE (copy) = TREE_ADDRESSABLE (decl); TREE_READONLY (copy) = TREE_READONLY (decl); TREE_THIS_VOLATILE (copy) = TREE_THIS_VOLATILE (decl); + DECL_COMPLEX_GIMPLE_REG_P (copy) = DECL_COMPLEX_GIMPLE_REG_P (decl); } else { diff --git a/gcc/tree-complex.c b/gcc/tree-complex.c index 4dd217d..e3e6741 100644 --- a/gcc/tree-complex.c +++ b/gcc/tree-complex.c @@ -21,54 +21,424 @@ Software Foundation, 59 Temple Place - Suite 330, Boston, MA #include "config.h" #include "system.h" #include "coretypes.h" -#include "tree.h" #include "tm.h" +#include "tree.h" #include "rtl.h" -#include "expr.h" -#include "insn-codes.h" -#include "diagnostic.h" -#include "optabs.h" -#include "machmode.h" -#include "langhooks.h" +#include "real.h" +#include "flags.h" #include "tree-flow.h" #include "tree-gimple.h" #include "tree-iterator.h" #include "tree-pass.h" -#include "flags.h" -#include "ggc.h" +#include "tree-ssa-propagate.h" + + +/* For each complex ssa name, a lattice value. We're interested in finding + out whether a complex number is degenerate in some way, having only real + or only complex parts. */ + +typedef enum +{ + UNINITIALIZED = 0, + ONLY_REAL = 1, + ONLY_IMAG = 2, + VARYING = 3 +} complex_lattice_t; + +#define PAIR(a, b) ((a) << 2 | (b)) + +DEF_VEC_I(complex_lattice_t); +DEF_VEC_ALLOC_I(complex_lattice_t, heap); + +static VEC(complex_lattice_t, heap) *complex_lattice_values; + +/* For each complex variable, a pair of variables for the components. */ +static VEC(tree, heap) *complex_variable_components; + + +/* Return true if T is not a zero constant. In the case of real values, + we're only interested in +0.0. */ + +static int +some_nonzerop (tree t) +{ + int zerop = false; + + if (TREE_CODE (t) == REAL_CST) + zerop = REAL_VALUES_IDENTICAL (TREE_REAL_CST (t), dconst0); + else if (TREE_CODE (t) == INTEGER_CST) + zerop = integer_zerop (t); + + return !zerop; +} + +/* Compute a lattice value from T. It may be a gimple_val, or, as a + special exception, a COMPLEX_EXPR. */ +static complex_lattice_t +find_lattice_value (tree t) +{ + tree real, imag; + int r, i; + complex_lattice_t ret; + + switch (TREE_CODE (t)) + { + case SSA_NAME: + return VEC_index (complex_lattice_t, complex_lattice_values, + SSA_NAME_VERSION (t)); + + case COMPLEX_CST: + real = TREE_REALPART (t); + imag = TREE_IMAGPART (t); + break; + + case COMPLEX_EXPR: + real = TREE_OPERAND (t, 0); + imag = TREE_OPERAND (t, 1); + break; + + default: + gcc_unreachable (); + } + + r = some_nonzerop (real); + i = some_nonzerop (imag); + ret = r*ONLY_REAL + i*ONLY_IMAG; + + /* ??? On occasion we could do better than mapping 0+0i to real, but we + certainly don't want to leave it UNINITIALIZED, which eventually gets + mapped to VARYING. */ + if (ret == UNINITIALIZED) + ret = ONLY_REAL; + + return ret; +} + +/* Determine if LHS is something for which we're interested in seeing + simulation results. */ + +static bool +is_complex_reg (tree lhs) +{ + return TREE_CODE (TREE_TYPE (lhs)) == COMPLEX_TYPE && is_gimple_reg (lhs); +} + +/* Mark the incoming parameters to the function as VARYING. */ + +static void +init_parameter_lattice_values (void) +{ + tree parm; + + for (parm = DECL_ARGUMENTS (cfun->decl); parm ; parm = TREE_CHAIN (parm)) + if (is_complex_reg (parm) && var_ann (parm) != NULL) + { + tree ssa_name = default_def (parm); + VEC_replace (complex_lattice_t, complex_lattice_values, + SSA_NAME_VERSION (ssa_name), VARYING); + } +} + +/* Initialize DONT_SIMULATE_AGAIN for each stmt and phi. Return false if + we found no statements we want to simulate, and thus there's nothing for + the entire pass to do. */ + +static bool +init_dont_simulate_again (void) +{ + basic_block bb; + block_stmt_iterator bsi; + tree phi; + bool saw_a_complex_value = false; + + FOR_EACH_BB (bb) + { + for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi)) + DONT_SIMULATE_AGAIN (phi) = !is_complex_reg (PHI_RESULT (phi)); + + for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi)) + { + tree stmt = bsi_stmt (bsi); + bool dsa = true; + + if (TREE_CODE (stmt) == MODIFY_EXPR + && is_complex_reg (TREE_OPERAND (stmt, 0))) + { + dsa = false; + saw_a_complex_value = true; + } + + DONT_SIMULATE_AGAIN (stmt) = dsa; + } + } + + return saw_a_complex_value; +} + + +/* Evaluate statement STMT against the complex lattice defined above. */ + +static enum ssa_prop_result +complex_visit_stmt (tree stmt, edge *taken_edge_p ATTRIBUTE_UNUSED, + tree *result_p) +{ + complex_lattice_t new_l, old_l, op1_l, op2_l; + unsigned int ver; + tree lhs, rhs; + + /* These conditions should be satisfied due to the initial filter + set up in init_dont_simulate_again. */ + gcc_assert (TREE_CODE (stmt) == MODIFY_EXPR); + + lhs = TREE_OPERAND (stmt, 0); + rhs = TREE_OPERAND (stmt, 1); + + gcc_assert (TREE_CODE (lhs) == SSA_NAME); + gcc_assert (TREE_CODE (TREE_TYPE (lhs)) == COMPLEX_TYPE); + + *result_p = lhs; + ver = SSA_NAME_VERSION (lhs); + old_l = VEC_index (complex_lattice_t, complex_lattice_values, ver); + + switch (TREE_CODE (rhs)) + { + case SSA_NAME: + case COMPLEX_EXPR: + case COMPLEX_CST: + new_l = find_lattice_value (rhs); + break; + + case PLUS_EXPR: + case MINUS_EXPR: + op1_l = find_lattice_value (TREE_OPERAND (rhs, 0)); + op2_l = find_lattice_value (TREE_OPERAND (rhs, 1)); + + /* We've set up the lattice values such that IOR neatly + models addition. */ + new_l = op1_l | op2_l; + break; + + case MULT_EXPR: + case RDIV_EXPR: + case TRUNC_DIV_EXPR: + case CEIL_DIV_EXPR: + case FLOOR_DIV_EXPR: + case ROUND_DIV_EXPR: + op1_l = find_lattice_value (TREE_OPERAND (rhs, 0)); + op2_l = find_lattice_value (TREE_OPERAND (rhs, 1)); + + /* Obviously, if either varies, so does the result. */ + if (op1_l == VARYING || op2_l == VARYING) + new_l = VARYING; + /* Don't prematurely promote variables if we've not yet seen + their inputs. */ + else if (op1_l == UNINITIALIZED) + new_l = op2_l; + else if (op2_l == UNINITIALIZED) + new_l = op1_l; + else + { + /* At this point both numbers have only one component. If the + numbers are of opposite kind, the result is imaginary, + otherwise the result is real. The add/subtract translates + the real/imag from/to 0/1; the ^ performs the comparison. */ + new_l = ((op1_l - ONLY_REAL) ^ (op2_l - ONLY_REAL)) + ONLY_REAL; + + /* Don't allow the lattice value to flip-flop indefinitely. */ + new_l |= old_l; + } + break; + + case NEGATE_EXPR: + case CONJ_EXPR: + new_l = find_lattice_value (TREE_OPERAND (rhs, 0)); + break; + + default: + new_l = VARYING; + break; + } + + /* If nothing changed this round, let the propagator know. */ + if (new_l == old_l) + return SSA_PROP_NOT_INTERESTING; + + VEC_replace (complex_lattice_t, complex_lattice_values, ver, new_l); + return new_l == VARYING ? SSA_PROP_VARYING : SSA_PROP_INTERESTING; +} + +/* Evaluate a PHI node against the complex lattice defined above. */ + +static enum ssa_prop_result +complex_visit_phi (tree phi) +{ + complex_lattice_t new_l, old_l; + unsigned int ver; + tree lhs; + int i; + + lhs = PHI_RESULT (phi); + + /* This condition should be satisfied due to the initial filter + set up in init_dont_simulate_again. */ + gcc_assert (TREE_CODE (TREE_TYPE (lhs)) == COMPLEX_TYPE); + + /* We've set up the lattice values such that IOR neatly models PHI meet. */ + new_l = UNINITIALIZED; + for (i = PHI_NUM_ARGS (phi) - 1; i >= 0; --i) + new_l |= find_lattice_value (PHI_ARG_DEF (phi, i)); + + ver = SSA_NAME_VERSION (lhs); + old_l = VEC_index (complex_lattice_t, complex_lattice_values, ver); + + if (new_l == old_l) + return SSA_PROP_NOT_INTERESTING; + + VEC_replace (complex_lattice_t, complex_lattice_values, ver, new_l); + return new_l == VARYING ? SSA_PROP_VARYING : SSA_PROP_INTERESTING; +} + +/* For each referenced complex gimple register, set up a pair of registers + to hold the components of the complex value. */ + +static void +create_components (void) +{ + size_t k, n; + + n = num_referenced_vars; + complex_variable_components = VEC_alloc (tree, heap, 2*n); + VEC_safe_grow (tree, heap, complex_variable_components, 2*n); + + for (k = 0; k < n; ++k) + { + tree var = referenced_var (k); + tree r = NULL, i = NULL; + + if (var != NULL + && TREE_CODE (TREE_TYPE (var)) == COMPLEX_TYPE + && is_gimple_reg (var)) + { + tree inner_type = TREE_TYPE (TREE_TYPE (var)); + + r = make_rename_temp (inner_type, "CR"); + i = make_rename_temp (inner_type, "CI"); + DECL_SOURCE_LOCATION (r) = DECL_SOURCE_LOCATION (var); + DECL_SOURCE_LOCATION (i) = DECL_SOURCE_LOCATION (var); + DECL_ARTIFICIAL (r) = 1; + DECL_ARTIFICIAL (i) = 1; + + if (DECL_NAME (var) && !DECL_IGNORED_P (var)) + { + const char *name = IDENTIFIER_POINTER (DECL_NAME (var)); + + DECL_NAME (r) = get_identifier (ACONCAT ((name, "$real", NULL))); + DECL_NAME (i) = get_identifier (ACONCAT ((name, "$imag", NULL))); + + SET_DECL_DEBUG_EXPR (r, build1 (REALPART_EXPR, inner_type, var)); + SET_DECL_DEBUG_EXPR (i, build1 (IMAGPART_EXPR, inner_type, var)); + DECL_DEBUG_EXPR_IS_FROM (r) = 1; + DECL_DEBUG_EXPR_IS_FROM (i) = 1; + + DECL_IGNORED_P (r) = 0; + DECL_IGNORED_P (i) = 0; + + TREE_NO_WARNING (r) = TREE_NO_WARNING (var); + TREE_NO_WARNING (i) = TREE_NO_WARNING (var); + } + else + { + DECL_IGNORED_P (r) = 1; + DECL_IGNORED_P (i) = 1; + TREE_NO_WARNING (r) = 1; + TREE_NO_WARNING (i) = 1; + } + } + + VEC_replace (tree, complex_variable_components, 2*k, r); + VEC_replace (tree, complex_variable_components, 2*k + 1, i); + } +} /* Extract the real or imaginary part of a complex variable or constant. Make sure that it's a proper gimple_val and gimplify it if not. Emit any new code before BSI. */ static tree -extract_component (block_stmt_iterator *bsi, tree t, bool imagpart_p) +extract_component (block_stmt_iterator *bsi, tree t, bool imagpart_p, + bool gimple_p) { - tree ret, inner_type; - - inner_type = TREE_TYPE (TREE_TYPE (t)); switch (TREE_CODE (t)) { case COMPLEX_CST: - ret = (imagpart_p ? TREE_IMAGPART (t) : TREE_REALPART (t)); - break; + return imagpart_p ? TREE_IMAGPART (t) : TREE_REALPART (t); case COMPLEX_EXPR: - ret = TREE_OPERAND (t, imagpart_p); - break; + return TREE_OPERAND (t, imagpart_p); case VAR_DECL: case PARM_DECL: - ret = build1 ((imagpart_p ? IMAGPART_EXPR : REALPART_EXPR), - inner_type, t); - break; + case INDIRECT_REF: + case COMPONENT_REF: + case ARRAY_REF: + { + tree inner_type = TREE_TYPE (TREE_TYPE (t)); + + t = build1 ((imagpart_p ? IMAGPART_EXPR : REALPART_EXPR), + inner_type, unshare_expr (t)); + + if (gimple_p) + t = gimplify_val (bsi, inner_type, t); + + return t; + } + + case SSA_NAME: + { + tree def = SSA_NAME_DEF_STMT (t); + + if (TREE_CODE (def) == MODIFY_EXPR) + { + def = TREE_OPERAND (def, 1); + if (TREE_CODE (def) == COMPLEX_CST) + return imagpart_p ? TREE_IMAGPART (def) : TREE_REALPART (def); + if (TREE_CODE (def) == COMPLEX_EXPR) + { + def = TREE_OPERAND (def, imagpart_p); + if (TREE_CONSTANT (def)) + return def; + } + } + + return VEC_index (tree, complex_variable_components, + var_ann (SSA_NAME_VAR (t))->uid * 2 + imagpart_p); + } default: gcc_unreachable (); } +} + +/* Update the complex components of the ssa name on the lhs of STMT. */ - return gimplify_val (bsi, inner_type, ret); +static void +update_complex_components (block_stmt_iterator *bsi, tree stmt, tree r, tree i) +{ + unsigned int uid = var_ann (SSA_NAME_VAR (TREE_OPERAND (stmt, 0)))->uid; + tree v, x; + + v = VEC_index (tree, complex_variable_components, 2*uid); + x = build2 (MODIFY_EXPR, TREE_TYPE (v), v, r); + SET_EXPR_LOCUS (x, EXPR_LOCUS (stmt)); + TREE_BLOCK (x) = TREE_BLOCK (stmt); + bsi_insert_after (bsi, x, BSI_NEW_STMT); + + v = VEC_index (tree, complex_variable_components, 2*uid + 1); + x = build2 (MODIFY_EXPR, TREE_TYPE (v), v, i); + SET_EXPR_LOCUS (x, EXPR_LOCUS (stmt)); + TREE_BLOCK (x) = TREE_BLOCK (stmt); + bsi_insert_after (bsi, x, BSI_NEW_STMT); } /* Update an assignment to a complex variable in place. */ @@ -76,15 +446,161 @@ extract_component (block_stmt_iterator *bsi, tree t, bool imagpart_p) static void update_complex_assignment (block_stmt_iterator *bsi, tree r, tree i) { - tree stmt = bsi_stmt (*bsi); + tree stmt, mod; tree type; + mod = stmt = bsi_stmt (*bsi); if (TREE_CODE (stmt) == RETURN_EXPR) - stmt = TREE_OPERAND (stmt, 0); + mod = TREE_OPERAND (mod, 0); + else if (in_ssa_p) + update_complex_components (bsi, stmt, r, i); - type = TREE_TYPE (TREE_OPERAND (stmt, 1)); - TREE_OPERAND (stmt, 1) = build (COMPLEX_EXPR, type, r, i); - mark_stmt_modified (stmt); + type = TREE_TYPE (TREE_OPERAND (mod, 1)); + TREE_OPERAND (mod, 1) = build (COMPLEX_EXPR, type, r, i); + update_stmt (stmt); +} + +/* Generate code at the entry point of the function to initialize the + component variables for a complex parameter. */ + +static void +update_parameter_components (void) +{ + edge entry_edge = single_succ_edge (ENTRY_BLOCK_PTR); + tree parm; + + for (parm = DECL_ARGUMENTS (cfun->decl); parm ; parm = TREE_CHAIN (parm)) + { + tree type = TREE_TYPE (parm); + tree ssa_name, x, y; + unsigned int uid; + + if (TREE_CODE (type) != COMPLEX_TYPE || !is_gimple_reg (parm)) + continue; + + type = TREE_TYPE (type); + ssa_name = default_def (parm); + uid = var_ann (parm)->uid; + + x = VEC_index (tree, complex_variable_components, 2*uid); + y = build1 (REALPART_EXPR, type, ssa_name); + bsi_insert_on_edge (entry_edge, build2 (MODIFY_EXPR, type, x, y)); + + x = VEC_index (tree, complex_variable_components, 2*uid + 1); + y = build1 (IMAGPART_EXPR, type, ssa_name); + bsi_insert_on_edge (entry_edge, build2 (MODIFY_EXPR, type, x, y)); + } +} + +/* Generate code to set the component variables of a complex variable + to match the PHI statements in block BB. */ + +static void +update_phi_components (basic_block bb) +{ + tree phi; + + for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi)) + if (is_complex_reg (PHI_RESULT (phi))) + { + unsigned int i, n, uid; + tree real, imag, type; + + uid = var_ann (SSA_NAME_VAR (PHI_RESULT (phi)))->uid; + real = VEC_index (tree, complex_variable_components, 2*uid); + imag = VEC_index (tree, complex_variable_components, 2*uid + 1); + type = TREE_TYPE (real); + + for (i = 0, n = PHI_NUM_ARGS (phi); i < n; ++i) + { + edge e = PHI_ARG_EDGE (phi, i); + tree arg = PHI_ARG_DEF (phi, i); + tree x; + + x = extract_component (NULL, arg, 0, false); + if (real != x) + bsi_insert_on_edge (e, build2 (MODIFY_EXPR, type, real, x)); + + x = extract_component (NULL, arg, 1, false); + if (imag != x) + bsi_insert_on_edge (e, build2 (MODIFY_EXPR, type, imag, x)); + } + } +} + +/* Mark each virtual op in STMT for ssa update. */ + +static void +update_all_vops (tree stmt) +{ + ssa_op_iter iter; + tree sym; + + FOR_EACH_SSA_TREE_OPERAND (sym, stmt, iter, SSA_OP_ALL_VIRTUALS) + { + if (TREE_CODE (sym) == SSA_NAME) + sym = SSA_NAME_VAR (sym); + mark_sym_for_renaming (sym); + } +} + +/* Expand a complex move to scalars. */ + +static void +expand_complex_move (block_stmt_iterator *bsi, tree stmt, tree type, + tree lhs, tree rhs) +{ + tree inner_type = TREE_TYPE (type); + tree r, i; + + if (TREE_CODE (lhs) == SSA_NAME) + { + if (TREE_CODE (rhs) == CALL_EXPR || TREE_SIDE_EFFECTS (rhs)) + { + r = build1 (REALPART_EXPR, inner_type, unshare_expr (lhs)); + i = build1 (IMAGPART_EXPR, inner_type, unshare_expr (lhs)); + update_complex_components (bsi, stmt, r, i); + } + else + { + update_all_vops (bsi_stmt (*bsi)); + r = extract_component (bsi, rhs, 0, true); + i = extract_component (bsi, rhs, 1, true); + update_complex_assignment (bsi, r, i); + } + } + else if (TREE_CODE (rhs) == SSA_NAME && !TREE_SIDE_EFFECTS (lhs)) + { + tree x; + + r = extract_component (bsi, rhs, 0, false); + i = extract_component (bsi, rhs, 1, false); + + x = build1 (REALPART_EXPR, inner_type, unshare_expr (lhs)); + x = build2 (MODIFY_EXPR, inner_type, x, r); + bsi_insert_before (bsi, x, BSI_SAME_STMT); + + if (stmt == bsi_stmt (*bsi)) + { + x = build1 (IMAGPART_EXPR, inner_type, unshare_expr (lhs)); + TREE_OPERAND (stmt, 0) = x; + TREE_OPERAND (stmt, 1) = i; + TREE_TYPE (stmt) = inner_type; + } + else + { + x = build1 (IMAGPART_EXPR, inner_type, unshare_expr (lhs)); + x = build2 (MODIFY_EXPR, inner_type, x, i); + bsi_insert_before (bsi, x, BSI_SAME_STMT); + + stmt = bsi_stmt (*bsi); + gcc_assert (TREE_CODE (stmt) == RETURN_EXPR); + TREE_OPERAND (stmt, 0) = lhs; + } + + update_all_vops (stmt); + update_stmt (stmt); + } } /* Expand complex addition to scalars: @@ -95,12 +611,72 @@ update_complex_assignment (block_stmt_iterator *bsi, tree r, tree i) static void expand_complex_addition (block_stmt_iterator *bsi, tree inner_type, tree ar, tree ai, tree br, tree bi, - enum tree_code code) + enum tree_code code, + complex_lattice_t al, complex_lattice_t bl) { tree rr, ri; - rr = gimplify_build2 (bsi, code, inner_type, ar, br); - ri = gimplify_build2 (bsi, code, inner_type, ai, bi); + switch (PAIR (al, bl)) + { + case PAIR (ONLY_REAL, ONLY_REAL): + rr = gimplify_build2 (bsi, code, inner_type, ar, br); + ri = ai; + break; + + case PAIR (ONLY_REAL, ONLY_IMAG): + rr = ar; + if (code == MINUS_EXPR) + ri = gimplify_build2 (bsi, MINUS_EXPR, inner_type, ai, bi); + else + ri = bi; + break; + + case PAIR (ONLY_IMAG, ONLY_REAL): + if (code == MINUS_EXPR) + rr = gimplify_build2 (bsi, MINUS_EXPR, inner_type, ar, br); + else + rr = br; + ri = ai; + break; + + case PAIR (ONLY_IMAG, ONLY_IMAG): + rr = ar; + ri = gimplify_build2 (bsi, code, inner_type, ai, bi); + break; + + case PAIR (VARYING, ONLY_REAL): + rr = gimplify_build2 (bsi, code, inner_type, ar, br); + ri = ai; + break; + + case PAIR (VARYING, ONLY_IMAG): + rr = ar; + ri = gimplify_build2 (bsi, MINUS_EXPR, inner_type, ai, bi); + break; + + case PAIR (ONLY_REAL, VARYING): + if (code == MINUS_EXPR) + goto general; + rr = gimplify_build2 (bsi, code, inner_type, ar, br); + ri = bi; + break; + + case PAIR (ONLY_IMAG, VARYING): + if (code == MINUS_EXPR) + goto general; + rr = br; + ri = gimplify_build2 (bsi, MINUS_EXPR, inner_type, ai, bi); + break; + + case PAIR (VARYING, VARYING): + general: + rr = gimplify_build2 (bsi, code, inner_type, ar, br); + ri = gimplify_build2 (bsi, code, inner_type, ai, bi); + break; + + default: + gcc_unreachable (); + } update_complex_assignment (bsi, rr, ri); } @@ -137,6 +713,14 @@ expand_complex_libcall (block_stmt_iterator *bsi, tree ar, tree ai, TREE_OPERAND (stmt, 1) = build3 (CALL_EXPR, type, build_fold_addr_expr (fn), args, NULL); update_stmt (stmt); + + if (in_ssa_p) + { + tree lhs = TREE_OPERAND (stmt, 0); + update_complex_components (bsi, stmt, + build1 (REALPART_EXPR, type, lhs), + build1 (IMAGPART_EXPR, type, lhs)); + } } /* Expand complex multiplication to scalars: @@ -145,29 +729,81 @@ expand_complex_libcall (block_stmt_iterator *bsi, tree ar, tree ai, static void expand_complex_multiplication (block_stmt_iterator *bsi, tree inner_type, - tree ar, tree ai, tree br, tree bi) + tree ar, tree ai, tree br, tree bi, + complex_lattice_t al, complex_lattice_t bl) { - tree t1, t2, t3, t4, rr, ri; + tree rr, ri; - if (flag_complex_method == 2 && SCALAR_FLOAT_TYPE_P (inner_type)) + if (al < bl) { - expand_complex_libcall (bsi, ar, ai, br, bi, MULT_EXPR); - return; + complex_lattice_t tl; + rr = ar, ar = br, br = rr; + ri = ai, ai = bi, bi = ri; + tl = al, al = bl, bl = tl; } - t1 = gimplify_build2 (bsi, MULT_EXPR, inner_type, ar, br); - t2 = gimplify_build2 (bsi, MULT_EXPR, inner_type, ai, bi); - t3 = gimplify_build2 (bsi, MULT_EXPR, inner_type, ar, bi); + switch (PAIR (al, bl)) + { + case PAIR (ONLY_REAL, ONLY_REAL): + rr = gimplify_build2 (bsi, MULT_EXPR, inner_type, ar, br); + ri = ai; + break; - /* Avoid expanding redundant multiplication for the common - case of squaring a complex number. */ - if (ar == br && ai == bi) - t4 = t3; - else - t4 = gimplify_build2 (bsi, MULT_EXPR, inner_type, ai, br); + case PAIR (ONLY_IMAG, ONLY_REAL): + rr = ar; + if (TREE_CODE (ai) == REAL_CST + && REAL_VALUES_IDENTICAL (TREE_REAL_CST (ai), dconst1)) + ri = br; + else + ri = gimplify_build2 (bsi, MULT_EXPR, inner_type, ai, br); + break; - rr = gimplify_build2 (bsi, MINUS_EXPR, inner_type, t1, t2); - ri = gimplify_build2 (bsi, PLUS_EXPR, inner_type, t3, t4); + case PAIR (ONLY_IMAG, ONLY_IMAG): + rr = gimplify_build2 (bsi, MULT_EXPR, inner_type, ai, bi); + rr = gimplify_build1 (bsi, NEGATE_EXPR, inner_type, rr); + ri = ar; + break; + + case PAIR (VARYING, ONLY_REAL): + rr = gimplify_build2 (bsi, MULT_EXPR, inner_type, ar, br); + ri = gimplify_build2 (bsi, MULT_EXPR, inner_type, ai, br); + break; + + case PAIR (VARYING, ONLY_IMAG): + rr = gimplify_build2 (bsi, MULT_EXPR, inner_type, ai, bi); + rr = gimplify_build1 (bsi, NEGATE_EXPR, inner_type, rr); + ri = gimplify_build2 (bsi, MULT_EXPR, inner_type, ar, bi); + break; + + case PAIR (VARYING, VARYING): + if (flag_complex_method == 2 && SCALAR_FLOAT_TYPE_P (inner_type)) + { + expand_complex_libcall (bsi, ar, ai, br, bi, MULT_EXPR); + return; + } + else + { + tree t1, t2, t3, t4; + + t1 = gimplify_build2 (bsi, MULT_EXPR, inner_type, ar, br); + t2 = gimplify_build2 (bsi, MULT_EXPR, inner_type, ai, bi); + t3 = gimplify_build2 (bsi, MULT_EXPR, inner_type, ar, bi); + + /* Avoid expanding redundant multiplication for the common + case of squaring a complex number. */ + if (ar == br && ai == bi) + t4 = t3; + else + t4 = gimplify_build2 (bsi, MULT_EXPR, inner_type, ai, br); + + rr = gimplify_build2 (bsi, MINUS_EXPR, inner_type, t1, t2); + ri = gimplify_build2 (bsi, PLUS_EXPR, inner_type, t3, t4); + } + break; + + default: + gcc_unreachable (); + } update_complex_assignment (bsi, rr, ri); } @@ -349,31 +985,77 @@ expand_complex_div_wide (block_stmt_iterator *bsi, tree inner_type, static void expand_complex_division (block_stmt_iterator *bsi, tree inner_type, tree ar, tree ai, tree br, tree bi, - enum tree_code code) + enum tree_code code, + complex_lattice_t al, complex_lattice_t bl) { - switch (flag_complex_method) + tree rr, ri; + + switch (PAIR (al, bl)) { - case 0: - /* straightforward implementation of complex divide acceptable. */ - expand_complex_div_straight (bsi, inner_type, ar, ai, br, bi, code); + case PAIR (ONLY_REAL, ONLY_REAL): + rr = gimplify_build2 (bsi, code, inner_type, ar, br); + ri = ai; break; - case 2: - if (SCALAR_FLOAT_TYPE_P (inner_type)) - { - expand_complex_libcall (bsi, ar, ai, br, bi, code); - return; - } - /* FALLTHRU */ + case PAIR (ONLY_REAL, ONLY_IMAG): + rr = ai; + ri = gimplify_build2 (bsi, code, inner_type, ar, bi); + ri = gimplify_build1 (bsi, NEGATE_EXPR, inner_type, ri); + break; + + case PAIR (ONLY_IMAG, ONLY_REAL): + rr = ar; + ri = gimplify_build2 (bsi, code, inner_type, ai, br); + break; - case 1: - /* wide ranges of inputs must work for complex divide. */ - expand_complex_div_wide (bsi, inner_type, ar, ai, br, bi, code); + case PAIR (ONLY_IMAG, ONLY_IMAG): + rr = gimplify_build2 (bsi, code, inner_type, ai, bi); + ri = ar; break; + case PAIR (VARYING, ONLY_REAL): + rr = gimplify_build2 (bsi, code, inner_type, ar, br); + ri = gimplify_build2 (bsi, code, inner_type, ai, br); + break; + + case PAIR (VARYING, ONLY_IMAG): + rr = gimplify_build2 (bsi, code, inner_type, ai, bi); + ri = gimplify_build2 (bsi, code, inner_type, ar, bi); + ri = gimplify_build1 (bsi, NEGATE_EXPR, inner_type, ri); + + case PAIR (ONLY_REAL, VARYING): + case PAIR (ONLY_IMAG, VARYING): + case PAIR (VARYING, VARYING): + switch (flag_complex_method) + { + case 0: + /* straightforward implementation of complex divide acceptable. */ + expand_complex_div_straight (bsi, inner_type, ar, ai, br, bi, code); + break; + + case 2: + if (SCALAR_FLOAT_TYPE_P (inner_type)) + { + expand_complex_libcall (bsi, ar, ai, br, bi, code); + break; + } + /* FALLTHRU */ + + case 1: + /* wide ranges of inputs must work for complex divide. */ + expand_complex_div_wide (bsi, inner_type, ar, ai, br, bi, code); + break; + + default: + gcc_unreachable (); + } + return; + default: gcc_unreachable (); } + + update_complex_assignment (bsi, rr, ri); } /* Expand complex negation to scalars: @@ -439,7 +1121,7 @@ expand_complex_comparison (block_stmt_iterator *bsi, tree ar, tree ai, gcc_unreachable (); } - mark_stmt_modified (stmt); + update_stmt (stmt); } /* Process one statement. If we identify a complex operation, expand it. */ @@ -450,6 +1132,7 @@ expand_complex_operations_1 (block_stmt_iterator *bsi) tree stmt = bsi_stmt (*bsi); tree rhs, type, inner_type; tree ac, ar, ai, bc, br, bi; + complex_lattice_t al, bl; enum tree_code code; switch (TREE_CODE (stmt)) @@ -503,14 +1186,30 @@ expand_complex_operations_1 (block_stmt_iterator *bsi) break; default: + { + tree lhs = TREE_OPERAND (stmt, 0); + tree rhs = TREE_OPERAND (stmt, 1); + + if (TREE_CODE (type) == COMPLEX_TYPE) + expand_complex_move (bsi, stmt, type, lhs, rhs); + else if ((TREE_CODE (rhs) == REALPART_EXPR + || TREE_CODE (rhs) == IMAGPART_EXPR) + && TREE_CODE (TREE_OPERAND (rhs, 0)) == SSA_NAME) + { + TREE_OPERAND (stmt, 1) + = extract_component (bsi, TREE_OPERAND (rhs, 0), + TREE_CODE (rhs) == IMAGPART_EXPR, false); + update_stmt (stmt); + } + } return; } /* Extract the components of the two complex values. Make sure and handle the common case of the same value used twice specially. */ ac = TREE_OPERAND (rhs, 0); - ar = extract_component (bsi, ac, 0); - ai = extract_component (bsi, ac, 1); + ar = extract_component (bsi, ac, 0, true); + ai = extract_component (bsi, ac, 1, true); if (TREE_CODE_CLASS (code) == tcc_unary) bc = br = bi = NULL; @@ -521,20 +1220,40 @@ expand_complex_operations_1 (block_stmt_iterator *bsi) br = ar, bi = ai; else { - br = extract_component (bsi, bc, 0); - bi = extract_component (bsi, bc, 1); + br = extract_component (bsi, bc, 0, true); + bi = extract_component (bsi, bc, 1, true); } } + if (in_ssa_p) + { + al = find_lattice_value (ac); + if (al == UNINITIALIZED) + al = VARYING; + + if (TREE_CODE_CLASS (code) == tcc_unary) + bl = UNINITIALIZED; + else if (ac == bc) + bl = al; + else + { + bl = find_lattice_value (bc); + if (bl == UNINITIALIZED) + bl = VARYING; + } + } + else + al = bl = VARYING; + switch (code) { case PLUS_EXPR: case MINUS_EXPR: - expand_complex_addition (bsi, inner_type, ar, ai, br, bi, code); + expand_complex_addition (bsi, inner_type, ar, ai, br, bi, code, al, bl); break; case MULT_EXPR: - expand_complex_multiplication (bsi, inner_type, ar, ai, br, bi); + expand_complex_multiplication (bsi, inner_type, ar, ai, br, bi, al, bl); break; case TRUNC_DIV_EXPR: @@ -542,7 +1261,7 @@ expand_complex_operations_1 (block_stmt_iterator *bsi) case FLOOR_DIV_EXPR: case ROUND_DIV_EXPR: case RDIV_EXPR: - expand_complex_division (bsi, inner_type, ar, ai, br, bi, code); + expand_complex_division (bsi, inner_type, ar, ai, br, bi, code, al, bl); break; case NEGATE_EXPR: @@ -561,25 +1280,48 @@ expand_complex_operations_1 (block_stmt_iterator *bsi) default: gcc_unreachable (); } - update_stmt_if_modified (stmt); } + +/* Entry point for complex operation lowering during optimization. */ + static void tree_lower_complex (void) { - int old_last_basic_block = last_basic_block; + int old_last_basic_block; block_stmt_iterator bsi; basic_block bb; + if (!init_dont_simulate_again ()) + return; + + complex_lattice_values = VEC_alloc (complex_lattice_t, heap, num_ssa_names); + VEC_safe_grow (complex_lattice_t, heap, + complex_lattice_values, num_ssa_names); + memset (VEC_address (complex_lattice_t, complex_lattice_values), 0, + num_ssa_names * sizeof(complex_lattice_t)); + init_parameter_lattice_values (); + + ssa_propagate (complex_visit_stmt, complex_visit_phi); + + create_components (); + update_parameter_components (); + + old_last_basic_block = last_basic_block; FOR_EACH_BB (bb) { if (bb->index >= old_last_basic_block) continue; + update_phi_components (bb); for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi)) expand_complex_operations_1 (&bsi); } -} + bsi_commit_edge_inserts (); + + VEC_free (tree, heap, complex_variable_components); + VEC_free (complex_lattice_t, heap, complex_lattice_values); +} struct tree_opt_pass pass_lower_complex = { @@ -590,6 +1332,50 @@ struct tree_opt_pass pass_lower_complex = NULL, /* next */ 0, /* static_pass_number */ 0, /* tv_id */ + PROP_ssa, /* properties_required */ + 0, /* properties_provided */ + 0, /* properties_destroyed */ + 0, /* todo_flags_start */ + TODO_dump_func | TODO_ggc_collect + | TODO_update_ssa + | TODO_verify_stmts, /* todo_flags_finish */ + 0 /* letter */ +}; + + +/* Entry point for complex operation lowering without optimization. */ + +static void +tree_lower_complex_O0 (void) +{ + int old_last_basic_block = last_basic_block; + block_stmt_iterator bsi; + basic_block bb; + + FOR_EACH_BB (bb) + { + if (bb->index >= old_last_basic_block) + continue; + for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi)) + expand_complex_operations_1 (&bsi); + } +} + +static bool +gate_no_optimization (void) +{ + return optimize == 0; +} + +struct tree_opt_pass pass_lower_complex_O0 = +{ + "cplxlower0", /* name */ + gate_no_optimization, /* gate */ + tree_lower_complex_O0, /* execute */ + NULL, /* sub */ + NULL, /* next */ + 0, /* static_pass_number */ + 0, /* tv_id */ PROP_cfg, /* properties_required */ 0, /* properties_provided */ 0, /* properties_destroyed */ diff --git a/gcc/tree-gimple.c b/gcc/tree-gimple.c index e723b47..3bf773b 100644 --- a/gcc/tree-gimple.c +++ b/gcc/tree-gimple.c @@ -260,12 +260,10 @@ is_gimple_id (tree t) bool is_gimple_reg_type (tree type) { - return (!AGGREGATE_TYPE_P (type) - && TREE_CODE (type) != COMPLEX_TYPE); + return !AGGREGATE_TYPE_P (type); } - -/* Return true if T is a scalar register variable. */ +/* Return true if T is a non-aggregate register variable. */ bool is_gimple_reg (tree t) @@ -275,6 +273,7 @@ is_gimple_reg (tree t) if (!is_gimple_variable (t)) return false; + if (!is_gimple_reg_type (TREE_TYPE (t))) return false; @@ -301,6 +300,11 @@ is_gimple_reg (tree t) if (TREE_CODE (t) == VAR_DECL && DECL_HARD_REGISTER (t)) return false; + /* Complex values must have been put into ssa form. That is, no + assignments to the individual components. */ + if (TREE_CODE (TREE_TYPE (t)) == COMPLEX_TYPE) + return DECL_COMPLEX_GIMPLE_REG_P (t); + return true; } diff --git a/gcc/tree-optimize.c b/gcc/tree-optimize.c index 76357fc..4284a58 100644 --- a/gcc/tree-optimize.c +++ b/gcc/tree-optimize.c @@ -375,7 +375,7 @@ init_tree_optimization_passes (void) NEXT_PASS (pass_lower_cf); NEXT_PASS (pass_lower_eh); NEXT_PASS (pass_build_cfg); - NEXT_PASS (pass_lower_complex); + NEXT_PASS (pass_lower_complex_O0); NEXT_PASS (pass_lower_vector); NEXT_PASS (pass_warn_function_return); NEXT_PASS (pass_tree_profile); @@ -417,6 +417,7 @@ init_tree_optimization_passes (void) NEXT_PASS (pass_profile); NEXT_PASS (pass_ch); NEXT_PASS (pass_stdarg); + NEXT_PASS (pass_lower_complex); NEXT_PASS (pass_sra); /* FIXME: SRA may generate arbitrary gimple code, exposing new aliased and call-clobbered variables. As mentioned below, diff --git a/gcc/tree-pass.h b/gcc/tree-pass.h index 12e2a58..0d2d8b8 100644 --- a/gcc/tree-pass.h +++ b/gcc/tree-pass.h @@ -192,6 +192,7 @@ extern struct tree_opt_pass pass_may_alias; extern struct tree_opt_pass pass_split_crit_edges; extern struct tree_opt_pass pass_pre; extern struct tree_opt_pass pass_profile; +extern struct tree_opt_pass pass_lower_complex_O0; extern struct tree_opt_pass pass_lower_complex; extern struct tree_opt_pass pass_lower_vector; extern struct tree_opt_pass pass_lower_vector_ssa; @@ -2353,6 +2353,14 @@ extern void decl_value_expr_insert (tree, tree); #define DECL_GIMPLE_FORMAL_TEMP_P(DECL) \ DECL_CHECK (DECL)->decl.gimple_formal_temp +/* For function local variables of COMPLEX type, indicates that the + variable is not aliased, and that all modifications to the variable + have been adjusted so that they are killing assignments. Thus the + variable may now be treated as a GIMPLE register, and use real + instead of virtual ops in SSA form. */ +#define DECL_COMPLEX_GIMPLE_REG_P(DECL) \ + DECL_CHECK (DECL)->decl.gimple_reg_flag + /* Enumerate visibility settings. */ #ifndef SYMBOL_VISIBILITY_DEFINED #define SYMBOL_VISIBILITY_DEFINED @@ -2424,8 +2432,9 @@ struct tree_decl GTY(()) unsigned returns_twice_flag : 1; unsigned seen_in_bind_expr : 1; unsigned novops_flag : 1; - unsigned has_value_expr:1; - /* 8 unused bits. */ + unsigned has_value_expr : 1; + unsigned gimple_reg_flag : 1; + /* 7 unused bits. */ union tree_decl_u1 { /* In a FUNCTION_DECL for which DECL_BUILT_IN holds, this is |