GCC Middle and Back End API Reference
gimplify.c File Reference
#include "tree-pass.h"
Include dependency graph for gimplify.c:

Data Structures

struct  gimplify_omp_ctx
struct  gimplify_init_ctor_preeval_data


typedef char * char_p


enum  gimplify_omp_var_data {
enum  omp_region_type {


static enum gimplify_status gimplify_compound_expr (tree *, gimple_seq *, bool)
void mark_addressable ()
void gimple_seq_add_stmt_without_update ()
static void gimplify_seq_add_stmt ()
static void gimplify_seq_add_seq ()
void push_gimplify_context ()
void pop_gimplify_context ()
static void gimple_push_bind_expr ()
static void gimple_pop_bind_expr ()
gimple gimple_current_bind_expr ()
vec< gimplegimple_bind_expr_stack ()
static bool gimple_conditional_context ()
static void gimple_push_condition ()
static void gimple_pop_condition ()
static int splay_tree_compare_decl_uid ()
static struct gimplify_omp_ctxnew_omp_context ()
static void delete_omp_context ()
static void omp_add_variable (struct gimplify_omp_ctx *, tree, unsigned int)
static bool omp_notice_variable (struct gimplify_omp_ctx *, tree, bool)
void gimplify_and_add ()
static gimple gimplify_and_return_first ()
static void remove_suffix ()
tree create_tmp_var_name ()
tree create_tmp_var_raw ()
tree create_tmp_var ()
tree create_tmp_reg ()
static bool is_gimple_reg_rhs ()
static bool is_gimple_mem_rhs ()
static bool is_gimple_reg_rhs_or_call ()
static bool is_gimple_mem_rhs_or_call ()
static tree create_tmp_from_val ()
static tree lookup_tmp_var ()
static tree internal_get_tmp_var (tree val, gimple_seq *pre_p, gimple_seq *post_p, bool is_formal)
tree get_formal_tmp_var ()
tree get_initialized_tmp_var ()
void declare_vars ()
static void force_constant_size ()
void gimple_add_tmp_var ()
static bool should_carry_location_p ()
static bool gimple_do_not_emit_location_p ()
static void gimple_set_do_not_emit_location ()
static void annotate_one_with_location ()
static void annotate_all_with_location_after (gimple_seq seq, gimple_stmt_iterator gsi, location_t location)
void annotate_all_with_location ()
static tree mostly_copy_tree_r ()
static tree copy_if_shared_r ()
static void copy_if_shared ()
static void unshare_body ()
static tree unmark_visited_r ()
static void unmark_visited ()
static void unvisit_body ()
tree unshare_expr ()
static tree prune_expr_location ()
tree unshare_expr_without_location ()
tree voidify_wrapper_expr ()
static void build_stack_save_restore ()
static enum gimplify_status gimplify_bind_expr ()
static enum gimplify_status gimplify_return_expr ()
static void gimplify_vla_decl ()
static enum gimplify_status gimplify_decl_expr ()
static enum gimplify_status gimplify_loop_expr ()
static enum gimplify_status gimplify_statement_list ()
static int compare_case_labels ()
void sort_case_labels ()
void preprocess_case_label_vec_for_gimple (vec< tree > labels, tree index_type, tree *default_casep)
static enum gimplify_status gimplify_switch_expr ()
static enum gimplify_status gimplify_case_label_expr ()
tree build_and_jump ()
static enum gimplify_status gimplify_exit_expr ()
tree force_labels_r ()
static void canonicalize_component_ref ()
static void canonicalize_addr_expr ()
static enum gimplify_status gimplify_conversion ()
static enum gimplify_status gimplify_var_or_parm_decl ()
static enum gimplify_status gimplify_compound_lval (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p, fallback_t fallback)
enum gimplify_status gimplify_self_mod_expr (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p, bool want_value, tree arith_type)
static void maybe_with_size_expr ()
static enum gimplify_status gimplify_arg ()
static enum gimplify_status gimplify_call_expr ()
static tree shortcut_cond_r (tree pred, tree *true_label_p, tree *false_label_p, location_t locus)
static tree shortcut_cond_expr ()
tree gimple_boolify ()
static enum gimplify_status gimplify_pure_cond_expr ()
static bool generic_expr_could_trap_p ()
static enum gimplify_status gimplify_cond_expr ()
static void prepare_gimple_addressable ()
static enum gimplify_status gimplify_modify_expr_to_memcpy (tree *expr_p, tree size, bool want_value, gimple_seq *seq_p)
static enum gimplify_status gimplify_modify_expr_to_memset (tree *expr_p, tree size, bool want_value, gimple_seq *seq_p)
static tree gimplify_init_ctor_preeval_1 ()
static void gimplify_init_ctor_preeval (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p, struct gimplify_init_ctor_preeval_data *data)
static void gimplify_init_ctor_eval (tree, vec< constructor_elt, va_gc > *, gimple_seq *, bool)
static void gimplify_init_ctor_eval_range (tree object, tree lower, tree upper, tree value, tree array_elt_type, gimple_seq *pre_p, bool cleared)
static bool zero_sized_field_decl ()
static bool zero_sized_type ()
gimple_predicate rhs_predicate_for ()
static enum gimplify_status gimplify_compound_literal_expr (tree *expr_p, gimple_seq *pre_p, bool(*gimple_test_f)(tree), fallback_t fallback)
static tree optimize_compound_literals_in_ctor ()
static enum gimplify_status gimplify_init_constructor (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p, bool want_value, bool notify_temp_creation)
static tree gimple_fold_indirect_ref_rhs ()
static enum gimplify_status gimplify_modify_expr_rhs (tree *expr_p, tree *from_p, tree *to_p, gimple_seq *pre_p, gimple_seq *post_p, bool want_value)
static bool is_gimple_stmt ()
static enum gimplify_status gimplify_modify_expr_complex_part (tree *expr_p, gimple_seq *pre_p, bool want_value)
static enum gimplify_status gimplify_modify_expr (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p, bool want_value)
static enum gimplify_status gimplify_variable_sized_compare ()
static enum gimplify_status gimplify_scalar_mode_aggregate_compare ()
static enum gimplify_status gimplify_compound_expr ()
static enum gimplify_status gimplify_save_expr ()
static enum gimplify_status gimplify_addr_expr ()
static enum gimplify_status gimplify_asm_expr ()
static enum gimplify_status gimplify_cleanup_point_expr ()
static void gimple_push_cleanup ()
static enum gimplify_status gimplify_target_expr ()
bool gimplify_stmt ()
void omp_firstprivatize_variable ()
static void omp_firstprivatize_type_sizes ()
static void omp_add_variable ()
static bool omp_notice_threadprivate_variable (struct gimplify_omp_ctx *ctx, tree decl, tree decl2)
static bool omp_notice_variable ()
static bool omp_is_private ()
static bool omp_check_private ()
static void gimplify_scan_omp_clauses (tree *list_p, gimple_seq *pre_p, enum omp_region_type region_type)
static int gimplify_adjust_omp_clauses_1 ()
static void gimplify_adjust_omp_clauses ()
static void gimplify_omp_parallel ()
static void gimplify_omp_task ()
static tree find_combined_omp_for ()
static enum gimplify_status gimplify_omp_for ()
static void gimplify_omp_workshare ()
static void gimplify_omp_target_update ()
static bool goa_lhs_expr_p ()
static int goa_stabilize_expr (tree *expr_p, gimple_seq *pre_p, tree lhs_addr, tree lhs_var)
static enum gimplify_status gimplify_omp_atomic ()
static enum gimplify_status gimplify_transaction ()
enum gimplify_status gimplify_expr (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p, bool(*gimple_test_f)(tree), fallback_t fallback)
void gimplify_type_sizes ()
void gimplify_one_sizepos ()
gimple gimplify_body ()
static bool flag_instrument_functions_exclude_p ()
void gimplify_function_tree ()
void gimple_regimplify_operands ()
tree force_gimple_operand_1 (tree expr, gimple_seq *stmts, gimple_predicate gimple_test_f, tree var)
tree force_gimple_operand ()
tree force_gimple_operand_gsi_1 (gimple_stmt_iterator *gsi, tree expr, gimple_predicate gimple_test_f, tree var, bool before, enum gsi_iterator_update m)
tree force_gimple_operand_gsi (gimple_stmt_iterator *gsi, tree expr, bool simple_p, tree var, bool before, enum gsi_iterator_update m)
static tree dummy_object ()
enum gimplify_status gimplify_va_arg_expr ()


static struct gimplify_ctxgimplify_ctxp
static struct gimplify_omp_ctxgimplify_omp_ctxp
static unsigned int tmp_var_id_num
static struct pointer_set_tnonlocal_vlas

Typedef Documentation

typedef char* char_p

Enumeration Type Documentation


Tree lowering pass. This pass converts the GENERIC functions-as-trees tree representation into the GIMPLE form. Copyright (C) 2002-2013 Free Software Foundation, Inc. Major work done by Sebastian Pop s.pop.nosp@m.@lap.nosp@m.oste..nosp@m.net, Diego Novillo dnovi.nosp@m.llo@.nosp@m.redha.nosp@m.t.co.nosp@m.m and Jason Merrill jason.nosp@m.@red.nosp@m.hat.c.nosp@m.om.

This file is part of GCC.

GCC is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3, or (at your option) any later version.

GCC is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with GCC; see the file COPYING3. If not see http://www.gnu.org/licenses/.


Function Documentation

void annotate_all_with_location ( )
   Set the location for all the statements in a sequence STMT_P to LOCATION.  

References pointer_set_insert().

static void annotate_all_with_location_after ( gimple_seq  seq,
gimple_stmt_iterator  gsi,
location_t  location 
   Set LOCATION for all the statements after iterator GSI in sequence
   SEQ.  If GSI is pointing to the end of the sequence, start with the
   first statement in SEQ.  
static void annotate_one_with_location ( )
   Set the location for gimple statement GS to LOCATION.  
tree build_and_jump ( )
   Build a GOTO to the LABEL_DECL pointed to by LABEL_P, building it first
   if necessary.  
       If there's nowhere to jump, just fall through.  
static void build_stack_save_restore ( )
   Prepare calls to builtins to SAVE and RESTORE the stack as well as
   a temporary through which they communicate.  

References build_constructor(), and gimplify_seq_add_stmt().

static void canonicalize_addr_expr ( )
   If a NOP conversion is changing a pointer to array of foo to a pointer
   to foo, embed that change in the ADDR_EXPR by converting
      T array[U];
      (T *)&array
   where L is the lower bound.  For simplicity, only do this for constant
   lower bound.
   The constraint is that the type of &array[L] is trivially convertible
   to T *.  
     We simplify only conversions from an ADDR_EXPR to a pointer type.  
     The addr_expr type should be a pointer to an array.  
     The pointer to element type shall be trivially convertible to
     the expression pointer type.  
     The lower bound and element sizes must be constant.  
     All checks succeeded.  Build a new node to merge the cast.  
     We can have stripped a required restrict qualifier above.  
static void canonicalize_component_ref ( )
   *EXPR_P is a COMPONENT_REF being used as an rvalue.  If its type is
   different from its canonical type, wrap the whole thing inside a
   NOP_EXPR and force the type of the COMPONENT_REF to be the canonical

   The canonical type of a COMPONENT_REF is the type of the field being
   referenced--unless the field is a bit-field which can be read directly
   in a smaller mode, in which case the canonical type is the
   sign-appropriate type corresponding to that mode.  
     One could argue that all the stuff below is not necessary for
     the non-bitfield case and declare it a FE error if type
     adjustment would be needed.  
         We need to preserve qualifiers and propagate them from
         operand 0.  
         Set the type of the COMPONENT_REF to the underlying type.  
         It is now a FE error, if the conversion from the canonical
         type to the original expression type is not useless.  

References copy(), copy_node(), current_function_decl, decl_function_context(), lang_hooks::dup_lang_specific_decl, gimplify_omp_ctxp, GS_ALL_DONE, GS_ERROR, omp_notice_variable(), ORT_SIMD, ORT_WORKSHARE, gimplify_omp_ctx::outer_context, pointer_set_insert(), gimplify_omp_ctx::region_type, seen_error(), and unshare_expr().

static int compare_case_labels ( )
   Compare two case labels.  Because the front end should already have
   made sure that case ranges do not overlap, it is enough to only compare
   the CASE_LOW values of each case label.  
     The 'default' case label always goes first.  
static void copy_if_shared ( )
   Unshare most of the shared trees rooted at *TP.  DATA is passed to the
   copy_if_shared_r callback unmodified.  

References mostly_copy_tree_r().

static tree copy_if_shared_r ( )
   Callback for walk_tree to unshare most of the shared trees rooted at *TP.
   If *TP has been visited already, then *TP is deeply copied by calling
   mostly_copy_tree_r.  DATA is passed to mostly_copy_tree_r unmodified.  
     Skip types, decls, and constants.  But we do want to look at their
     types and the bounds of types.  Mark them as visited so we properly
     unmark their subtrees on the unmark pass.  If we've already seen them,
     don't look down further.  
     If this node has been visited already, unshare it and don't look
     any deeper.  
     Otherwise, mark the node as visited and keep looking.  
static tree create_tmp_from_val ( )
   Create a temporary with a name derived from VAL.  Subroutine of
   lookup_tmp_var; nobody else should call this function.  
     Drop all qualifiers and address-space information from the value type.  

References gimple_temp_hash_elt::temp, and gimple_temp_hash_elt::val.

tree create_tmp_reg ( )
   Create a new temporary variable declaration of type TYPE by calling
   create_tmp_var and if TYPE is a vector or a complex number, mark the new
   temporary as gimple register.  
tree create_tmp_var ( )
   Create a new temporary variable declaration of type TYPE.  DO push the
   variable into the current binding.  Further, assume that this is called
   only from gimplification or optimization, at which point the creation of
   certain types are bugs.  
     We don't allow types that are addressable (meaning we can't make copies),
     or incomplete.  We also used to reject every variable size objects here,
     but now support those for which a constant upper bound can be obtained.
     The processing for variable sizes is performed in gimple_add_tmp_var,
     point at which it really matters and possibly reached via paths not going
     through this function, e.g. after direct calls to create_tmp_var_raw.  
tree create_tmp_var_name ( )
tree create_tmp_var_raw ( )
   Create a new temporary variable declaration of type TYPE.
   Do NOT push it into the current binding.  
     The variable was declared by the compiler.  
     And we don't want debug info for it.  
     Make the variable writable.  

References create_tmp_var_raw(), and gimple_add_tmp_var().

void declare_vars ( )
   Declare all the variables in VARS in SCOPE.  If DEBUG_INFO is true,
   generate debug info for them; otherwise don't.  
             We need to attach the nodes both to the BIND_EXPR and to its
             associated BLOCK for debugging purposes.  The key point here
             is that the BLOCK_VARS of the BIND_EXPR_BLOCK of a BIND_EXPR
             is a subchain of the BIND_EXPR_VARS of the BIND_EXPR.  
static void delete_omp_context ( )
   Destroy an omp construct that deals with variable remapping.  

References gimplify_and_add(), gsi_end_p(), gsi_next(), gsi_stmt(), and last.

static tree dummy_object ( )
   Return a dummy expression of type TYPE in order to keep going after an
static tree find_combined_omp_for ( )
   Helper function of gimplify_omp_for, find OMP_FOR resp. OMP_SIMD
   with non-NULL OMP_FOR_INIT.  
static bool flag_instrument_functions_exclude_p ( )
   Return whether we should exclude FNDECL from instrumentation.  
static void force_constant_size ( )
   For VAR a VAR_DECL of variable size, try to find a constant upper bound
   for the size and adjust DECL_SIZE/DECL_SIZE_UNIT accordingly.  Abort if
   no such upper bound can be obtained.  
     The only attempt we make is by querying the maximum size of objects
     of the variable's type.  
tree force_gimple_operand ( )
   Expand EXPR to list of gimple statements STMTS.  If SIMPLE is true,
   force the result to be either ssa_name or an invariant, otherwise
   just force it to be a rhs expression.  If VAR is not NULL, make the
   base variable of the final destination be VAR if suitable.  
tree force_gimple_operand_1 ( tree  expr,
gimple_seq stmts,
gimple_predicate  gimple_test_f,
tree  var 
   Expand EXPR to list of gimple statements STMTS.  GIMPLE_TEST_F specifies
   the predicate that will hold for the result.  If VAR is not NULL, make the
   base variable of the final destination be VAR if suitable.  
     gimple_test_f might be more strict than is_gimple_val, make
     sure we pass both.  Just checking gimple_test_f doesn't work
     because most gimple predicates do not work recursively.  

Referenced by add_to_predicate_list(), and vect_create_cond_for_alias_checks().

tree force_gimple_operand_gsi ( gimple_stmt_iterator gsi,
tree  expr,
bool  simple_p,
tree  var,
bool  before,
enum gsi_iterator_update  m 
   Invoke force_gimple_operand_1 for EXPR with parameter VAR.
   If SIMPLE is true, force the result to be either ssa_name or an invariant,
   otherwise just force it to be a rhs expression.  If some statements are
   produced, emits them at GSI.  If BEFORE is true, the statements are
   appended before GSI, otherwise they are appended after it.  M specifies
   the way GSI moves after insertion (GSI_SAME_STMT or GSI_CONTINUE_LINKING
   are the usual values).  

Referenced by build_one_array(), contains_vce_or_bfcref_p(), expand_omp_atomic_load(), expand_omp_sections(), generate_subtree_copies(), gimple_gen_one_value_profiler(), gimple_gen_pow2_profiler(), gimplify_mem_ref_parts(), ifcombine_ifandif(), nothing_to_prefetch_p(), sra_modify_expr(), update_dominators_in_loop(), and vect_can_advance_ivs_p().

tree force_gimple_operand_gsi_1 ( gimple_stmt_iterator gsi,
tree  expr,
gimple_predicate  gimple_test_f,
tree  var,
bool  before,
enum gsi_iterator_update  m 
   Invoke force_gimple_operand_1 for EXPR with parameters GIMPLE_TEST_F
   and VAR.  If some statements are produced, emits them at GSI.
   If BEFORE is true.  the statements are appended before GSI, otherwise
   they are appended after it.  M specifies the way GSI moves after
   insertion (GSI_SAME_STMT or GSI_CONTINUE_LINKING are the usual values).  

Referenced by create_mem_ref(), if_convertible_loop_p(), and insert_gimplified_predicates().

tree force_labels_r ( )
   A helper function to be called via walk_tree.  Mark all labels under *TP
   as being forced.  To be called for DECL_INITIAL of static variables.  
static bool generic_expr_could_trap_p ( )
   Return true if evaluating EXPR could trap.
   EXPR is GENERIC, while tree_could_trap_p can be called
   only on GIMPLE.  

References get_initialized_tmp_var(), handled_component_p(), and is_gimple_reg().

tree get_formal_tmp_var ( )
   Return a formal temporary variable initialized with VAL.  PRE_P is as
   in gimplify_expr.  Only use this function if:

   1) The value of the unfactored expression represented by VAL will not
      change between the initialization and use of the temporary, and
   2) The temporary will not be otherwise modified.

   For instance, #1 means that this is inappropriate for SAVE_EXPR temps,
   and #2 means it is inappropriate for && temps.

   For other cases, use get_initialized_tmp_var instead.  

References chainon(), gimple_bind_set_vars(), and gimple_bind_vars().

tree get_initialized_tmp_var ( )
   Return a temporary variable initialized with VAL.  PRE_P and POST_P
   are as in gimplify_expr.  
void gimple_add_tmp_var ( )
   Push the temporary variable TMP into the current binding.  
     Later processing assumes that the object size is constant, which might
     not be true at this point.  Force the use of a constant upper bound in
     this case.  
         Mark temporaries local within the nearest enclosing parallel.  
         This case is for nested functions.  We need to expose the locals
         they create.  
vec<gimple> gimple_bind_expr_stack ( void  )
   Return the stack of bindings created during gimplification.  

References gimplify_ctx::conditional_cleanups, gimplify_ctx::conditions, and gimple_seq_empty_p().

tree gimple_boolify ( )
   EXPR is used in a boolean context; make sure it has BOOLEAN_TYPE.  
         For __builtin_expect ((long) (x), y) recurse into x as well
         if x is truth_value_p.  
         Also boolify the arguments of truth exprs.  
         These expressions always produce boolean results.  
             There expressions always prduce boolean results.  
         Other expressions that get here must have boolean values, but
         might need to be converted to the appropriate mode.  
static bool gimple_conditional_context ( )
   Return true iff there is a COND_EXPR between us and the innermost
   CLEANUP_POINT_EXPR.  This info is used by gimple_push_cleanup.  
gimple gimple_current_bind_expr ( void  )
   Return the first element of the stack of bindings.  

References gimplify_ctx::conditions.

static bool gimple_do_not_emit_location_p ( )
   Return true if a location should not be emitted for this statement
   by annotate_one_with_location.  
static tree gimple_fold_indirect_ref_rhs ( )
   Given a pointer value OP0, return a simplified version of an
   indirection through OP0, or NULL_TREE if no simplification is
   possible.  This may only be applied to a rhs of an expression.
   Note that the resulting type may be different from the type pointed
   to in the sense that it is still compatible from the langhooks
   point of view. 
static void gimple_pop_bind_expr ( )
   Pop the first element off the stack of bindings.  
static void gimple_pop_condition ( )
   Note that we've left a COND_EXPR.  If we're back at unconditional scope
   now, add any conditional cleanups we've seen to the prequeue.  
static void gimple_push_bind_expr ( )
   Push a GIMPLE_BIND tuple onto the stack of bindings.  

References gimplify_ctx::bind_expr_stack.

static void gimple_push_cleanup ( )
   Insert a cleanup marker for gimplify_cleanup_point_expr.  CLEANUP
   is the cleanup action required.  EH_ONLY is true if the cleanup should
   only be executed if an exception is thrown, not on normal exit.  
     Errors can result in improperly nested cleanups.  Which results in
     confusion when trying to resolve the GIMPLE_WITH_CLEANUP_EXPR.  
         If we're in a conditional context, this is more complex.  We only
         want to run the cleanup if we actually ran the initialization that
         necessitates it, but we want to run it after the end of the
         conditional context.  So we wrap the try/finally around the
         condition and use a flag to determine whether or not to actually
         run the destructor.  Thus

           test ? f(A()) : 0

         becomes (approximately)

           flag = 0;
           try {
             if (test) { A::A(temp); flag = 1; val = f(temp); }
             else { val = 0; }
           } finally {
             if (flag) A::~A(temp);
         Because of this manipulation, and the EH edges that jump
         threading cannot redirect, the temporary (VAR) will appear
         to be used uninitialized.  Don't warn.  

References error(), GOVD_EXPLICIT, GOVD_MAP, and omp_add_variable().

static void gimple_push_condition ( )
   Note that we've entered a COND_EXPR.  
void gimple_regimplify_operands ( )
   Some transformations like inlining may invalidate the GIMPLE form
   for operands.  This function traverses all the operands in STMT and
   gimplifies anything that is not a valid gimple operand.  Any new
   GIMPLE statements are inserted before *GSI_P.  
         NOTE: We start gimplifying operands from last to first to
         make sure that side-effects on the RHS of calls, assignments
         and ASMs are executed before the LHS.  The ordering is not
         important for other statements.  
         If the LHS changed it in a way that requires a simple RHS,
         create temporary.  
void gimple_seq_add_stmt_without_update ( )
   Link gimple statement GS to the end of the sequence *SEQ_P.  If
   *SEQ_P is NULL, a new sequence is allocated.  This function is
   similar to gimple_seq_add_stmt, but does not scan the operands.
   During gimplification, we need to manipulate statement sequences
   before the def/use vectors have been constructed.  
static void gimple_set_do_not_emit_location ( )
   Mark statement G so a location will not be emitted by
     The PLF flags are initialized to 0 when a new tuple is created,
     so no need to initialize it anywhere.  
static enum gimplify_status gimplify_addr_expr ( )
   Rewrite the ADDR_EXPR node pointed to by EXPR_P

              : ...
              | '&' varname

    PRE_P points to the list where side effects that must happen before
        *EXPR_P should be stored.

    POST_P points to the list where side effects that must happen after
        *EXPR_P should be stored.  
         Check if we are dealing with an expression of the form '&*ptr'.
         While the front end folds away '&*ptr' into 'ptr', these
         expressions may be generated internally by the compiler (e.g.,
         builtins like __builtin_va_end).  
         Caution: the silent array decomposition semantics we allow for
         ADDR_EXPR means we can't always discard the pair.  
         Gimplification of the ADDR_EXPR operand may drop
         cv-qualification conversions, so make sure we add them if
         Take the address of our operand and then convert it to the type of
         this ADDR_EXPR.

         ??? The interactions of VIEW_CONVERT_EXPR and aliasing is not at
         all clear.  The impact of this transformation is even less clear.  
         If the operand is a useless conversion, look through it.  Doing so
         guarantees that the ADDR_EXPR and its operand will remain of the
         same type.  
         We use fb_either here because the C frontend sometimes takes
         the address of a call that returns a struct; see
         gcc.dg/c99-array-lval-1.c.  The gimplifier will correctly make
         the implied temporary explicit.  
         Make the operand addressable.  
         Then mark it.  Beware that it may not be possible to do so directly
         if a temporary has been created by the gimplification.  
         For various reasons, the gimplification of the expression
         may have made a new INDIRECT_REF.  
         The FEs may end up building ADDR_EXPRs early on a decl with
         an incomplete type.  Re-build ADDR_EXPRs in canonical form
         Make sure TREE_CONSTANT and TREE_SIDE_EFFECTS are set properly.  
         If we re-built the ADDR_EXPR add a conversion to the original type
         if required.  
static void gimplify_adjust_omp_clauses ( )
             Make sure OMP_CLAUSE_LASTPRIVATE_FIRSTPRIVATE is set to
             accurately reflect the presence of a FIRSTPRIVATE clause.  
                           We have to avoid assigning a shared variable
                           to itself when trying to add
     Add in any implicit data sharing.  
static int gimplify_adjust_omp_clauses_1 ( )
   For all variables that were not actually used within the context,
   remove PRIVATE, SHARED, and FIRSTPRIVATE clauses.  
void gimplify_and_add ( )
   Both gimplify the statement T and append it to *SEQ_P.  This function
   behaves exactly as gimplify_stmt, but you don't have to pass T as a
static gimple gimplify_and_return_first ( )
   Gimplify statement T into sequence *SEQ_P, and return the first
   tuple in the sequence of generated tuples for this statement.
   Return NULL if gimplifying T produced no tuples.  
static enum gimplify_status gimplify_arg ( )
   Helper for gimplify_call_expr.  Gimplify a single argument *ARG_P
   Store any side-effects in PRE_P.  CALL_LOCATION is the location of
   the CALL_EXPR.  
     In general, we allow lvalues for function arguments to avoid
     extra overhead of copying large aggregates out of even larger
     aggregates into temporaries only to copy the temporaries to
     the argument list.  Make optimizers happy by pulling out to
     temporaries those types that fit in registers.  
         Also strip a TARGET_EXPR that would force an extra copy.  
     If this is a variable sized type, we must remember the size.  
     FIXME diagnostics: This will mess up gcc.dg/Warray-bounds.c.  
     Make sure arguments have the same location as the function call
     There is a sequence point before a function call.  Side effects in
     the argument list must occur before the actual call. So, when
     gimplifying arguments, force gimplify_expr to use an internal
     post queue which is then appended to the end of PRE_P.  
static enum gimplify_status gimplify_asm_expr ( )
   Gimplify the operands of an ASM_EXPR.  Input operands should be a gimple
   value; output operands should be a gimple lvalue.  
             An input/output operand.  To give the optimizers more
             flexibility, split it into separate input and output
             Turn the in/out constraint into an output constraint.  
             And add a matching input constraint.  
                 If there are multiple alternatives in the constraint,
                 handle each of them individually.  Those that allow register
                 will be replaced with operand number, the others will stay
         If we can't make copies, we can only accept memory.  
         If the operand is a memory input, it should be an lvalue.  
     Do not add ASMs with errors to the gimple IL stream.  
static enum gimplify_status gimplify_bind_expr ( )
   Gimplify a BIND_EXPR.  Just voidify and recurse.  
     Mark variables seen in this bind expr.  
             Mark variable as local.  
         Preliminarily mark non-addressed complex variables as eligible
         for promotion to gimple registers.  We'll transform their uses
         as we find them.  
     Gimplify the body into the GIMPLE_BIND tuple's body.  
         Save stack on entry and restore it on exit.  Add a try_finally
         block to achieve this.  
     Add clobbers for all variables that go out of scope.  
             Only care for variables that have to be in memory.  Others
             will be rewritten into SSA names, hence moved to the top-level.  
gimple gimplify_body ( )
   Gimplify the body of statements of FNDECL and return a GIMPLE_BIND node
   containing the sequence of corresponding GIMPLE statements.  If DO_PARMS
   is true, also gimplify the parameters.  
     Initialize for optimize_insn_for_s{ize,peed}_p possibly called during
     Unshare most shared trees in the body and in that of any nested functions.
     It would seem we don't have to do this for nested functions because
     they are supposed to be output and then the outer function gimplified
     first, but the g++ front end doesn't always do it that way.  
     Make sure input_location isn't set to something weird.  
     Resolve callee-copies.  This has to be done before processing
     the body so that DECL_VALUE_EXPR gets processed correctly.  
     Gimplify the function's body.  
     The body must contain exactly one statement, a GIMPLE_BIND.  If this is
     not the case, wrap everything in a GIMPLE_BIND to make it so.  
     If we had callee-copies statements, insert them at the beginning
     of the function and clear DECL_VALUE_EXPR_P on the parameters.  
static enum gimplify_status gimplify_call_expr ( )
   Gimplify the CALL_EXPR node *EXPR_P into the GIMPLE sequence PRE_P.
   WANT_VALUE is true if the result of the call is desired.  
     For reliable diagnostics during inlining, it is necessary that
     every call_expr be annotated with file and line.  
     This may be a call to a builtin function.

     Builtin function calls may be transformed into different
     (and more efficient) builtin function calls under certain
     circumstances.  Unfortunately, gimplification can muck things
     up enough that the builtin expanders are not aware that certain
     transformations are still valid.

     So we attempt transformation/gimplification of the call before
     we gimplify the CALL_EXPR.  At this time we do not manage to
     transform all calls in the same manner as the expanders do, but
     we do transform most of them.  
             There was a transformation of this call which computes the
             same value, but in a more efficient way.  Return and try
     Remember the original function pointer type.  
     There is a sequence point before the call, so any side effects in
     the calling expression must occur before the actual call.  Force
     gimplify_expr to use an internal post queue.  
     Get argument types for verification.  
     If the last argument is __builtin_va_arg_pack () and it is not
     passed as a named argument, decrease the number of CALL_EXPR
     arguments and set instead the CALL_EXPR_VA_ARG_PACK flag.  
             Copy all CALL_EXPR flags, location and block, except
             CALL_EXPR_VA_ARG_PACK flag.  
             Set CALL_EXPR_VA_ARG_PACK.  
     Finally, gimplify the function arguments.  
             Avoid gimplifying the second argument to va_start, which needs to
             be the plain PARM_DECL.  
     Verify the function result.  
     Try this again in case gimplification exposed something.  
             There was a transformation of this call which computes the
             same value, but in a more efficient way.  Return and try
     If the function is "const" or "pure", then clear TREE_SIDE_EFFECTS on its
     decl.  This allows us to eliminate redundant or useless
     calls to "const" functions.  
             An infinite loop is considered a side effect.  
     If the value is not needed by the caller, emit a new GIMPLE_CALL
     and clear *EXPR_P.  Otherwise, leave *EXPR_P in its gimplified
     form and delegate the creation of a GIMPLE_CALL to
     gimplify_modify_expr.  This is always possible because when
     WANT_VALUE is true, the caller wants the result of this call into
     a temporary, which means that we will emit an INIT_EXPR in
     internal_get_tmp_var which will then be handled by
         The CALL_EXPR in *EXPR_P is already in GIMPLE form, so all we
         have to do is replicate it as a GIMPLE_CALL tuple.  
         Don't fold stmts inside of target construct.  We'll do it
         during omplower pass instead.  
       Remember the original function type.  

References GS_ERROR.

Referenced by gimplify_omp_workshare().

static enum gimplify_status gimplify_case_label_expr ( )
   Gimplify the CASE_LABEL_EXPR pointed to by EXPR_P.  
     Invalid OpenMP programs can play Duff's Device type games with
     #pragma omp parallel.  At least in the C front end, we don't
     detect such invalid branches until after gimplification.  
static enum gimplify_status gimplify_cleanup_point_expr ( )
   Gimplify a CLEANUP_POINT_EXPR.  Currently this works by adding
   GIMPLE_WITH_CLEANUP_EXPRs to the prequeue as we encounter cleanups while
   gimplifying the body, and converting them to TRY_FINALLY_EXPRs when we
   return to this function.

   FIXME should we complexify the prequeue handling instead?  Or use flags
   for all the cleanups and let the optimizer tighten them up?  The current
   code seems pretty fragile; it will break on a cleanup within any
   non-conditional nesting.  But any such nesting would be broken, anyway;
   we can't write a TRY_FINALLY_EXPR that starts inside a nesting construct
   and continues out of it.  We can do that at the RTL level, though, so
   having an optimizer to tighten up try/finally regions would be a Good
     We only care about the number of conditions between the innermost
     CLEANUP_POINT_EXPR and the cleanup.  So save and reset the count and
     any cleanups collected outside the CLEANUP_POINT_EXPR.  
                 Note that gsi_insert_seq_before and gsi_remove do not
                 scan operands, unlike some other sequence mutators.  
                 Do not use gsi_replace here, as it may scan operands.
                 We want to do a simple structural modification only.  
static enum gimplify_status gimplify_compound_expr ( tree ,
gimple_seq ,
   Forward declaration.  

Referenced by gimplify_omp_workshare().

static enum gimplify_status gimplify_compound_expr ( )
   Gimplify an expression sequence.  This function gimplifies each
   expression and rewrites the original expression with the last
   expression of the sequence in GIMPLE form.

   PRE_P points to the list where the side effects for all the
       expressions in the sequence will be emitted.

   WANT_VALUE is true when the result of the last COMPOUND_EXPR is used.  
static enum gimplify_status gimplify_compound_literal_expr ( tree expr_p,
gimple_seq pre_p,
bool(*)(tree gimple_test_f,
fallback_t  fallback 
   Gimplify a C99 compound literal expression.  This just means adding
   the DECL_EXPR before the current statement and using its anonymous
   decl instead.  
     Mark the decl as addressable if the compound literal
     expression is addressable now, otherwise it is marked too late
     after we gimplify the initialization expression.  
     Otherwise, if we don't need an lvalue and have a literal directly
     substitute it.  Check if it matches the gimple predicate, as
     otherwise we'd generate a new temporary, and we can as well just
     use the decl we already have.  
     Preliminarily mark non-addressed complex variables as eligible
     for promotion to gimple registers.  We'll transform their uses
     as we find them.  
     If the decl is not addressable, then it is being used in some
     expression or on the right hand side of a statement, and it can
     be put into a readonly data section.  
     This decl isn't mentioned in the enclosing block, so add it to the
     list of temps.  FIXME it seems a bit of a kludge to say that
     anonymous artificial vars aren't pushed, but everything else is.  

Referenced by gimplify_omp_workshare().

static enum gimplify_status gimplify_compound_lval ( tree expr_p,
gimple_seq pre_p,
gimple_seq post_p,
fallback_t  fallback 
   node *EXPR_P.

              : min_lval '[' val ']'
              | min_lval '.' ID
              | compound_lval '[' val ']'
              | compound_lval '.' ID

   This is not part of the original SIMPLE definition, which separates
   array and member references, but it seems reasonable to handle them
   together.  Also, this way we don't run into problems with union
   aliasing; gcc requires that for accesses through a union to alias, the
   union reference must be explicit, which was not always the case when we
   were splitting up array and member refs.

   PRE_P points to the sequence where side effects that must happen before
     *EXPR_P should be stored.

   POST_P points to the sequence where side effects that must happen after
     *EXPR_P should be stored.  
     Create a stack of the subexpressions so later we can walk them in
     order from inner to outer.  
     We can handle anything that get_inner_reference can deal with.  
         Fold INDIRECT_REFs now to turn them into ARRAY_REFs.  
         Expand DECL_VALUE_EXPR now.  In some cases that may expose
         additional COMPONENT_REFs.  
     Now EXPR_STACK is a stack of pointers to all the refs we've
     walked through and P points to the innermost expression.

     Java requires that we elaborated nodes in source order.  That
     means we must gimplify the inner expression followed by each of
     the indices, in order.  But we can't gimplify the inner
     expression until we deal with any variable bounds, sizes, or
     positions in order to deal with PLACEHOLDER_EXPRs.

     So we do this in three steps.  First we deal with the annotations
     for any variables in the components, then we gimplify the base,
     then we gimplify any indices, from left to right.  
             Gimplify the low bound and element type size and put them into
             the ARRAY_REF.  If these values are set, they have already been
                 Divide the element size by the alignment of the element
                 type (above).  
             Set the field offset into T and gimplify it.  
                 Divide the offset by its alignment.  
     Step 2 is to gimplify the base expression.  Make sure lvalue is set
     so as to match the min_lval predicate.  Failure to do so may result
     in the creation of large aggregate temporaries.  
     And finally, the indices and operands of ARRAY_REF.  During this
     loop we also remove any useless conversions.  
             Gimplify the dimension.  
         The innermost expression P may have originally had
         TREE_SIDE_EFFECTS set which would have caused all the outer
         expressions in *EXPR_P leading to P to also have had
         TREE_SIDE_EFFECTS set.  
     If the outermost expression is a COMPONENT_REF, canonicalize its type.  

Referenced by gimplify_omp_workshare().

static enum gimplify_status gimplify_cond_expr ( )
    Convert the conditional expression pointed to by EXPR_P '(p) ? a : b;'

    if (p)                      if (p)
      t1 = a;                     a;
    else                or      else
      t1 = b;                     b;

    The second form is used when *EXPR_P is of type void.

    PRE_P points to the list where side effects that must happen before
      *EXPR_P should be stored.  
     If this COND_EXPR has a value, copy the values into a temporary within
     the arms.  
         If either an rvalue is ok or we do not require an lvalue, create the
         temporary.  But we cannot do that if the type is addressable.  
                 If either branch has side effects or could trap, it can't be
                 evaluated unconditionally.  
         Otherwise, only create and copy references to the values.  
         Build the new then clause, `tmp = then_;'.  But don't build the
         assignment if the value is void; in C++ it can be if it's a throw.  
         Similarly, build the new else clause, `tmp = else_;'.  
         Move the COND_EXPR to the prequeue.  
     Remove any COMPOUND_EXPR so the following cases will be caught.  
     Make sure the condition has BOOLEAN_TYPE.  
     Break apart && and || conditions.  
             We can't rely on gimplify_expr to re-gimplify the expanded
             form properly, as cleanups might cause the target labels to be
             wrapped in a TRY_FINALLY_EXPR.  To prevent that, we need to
             set up a conditional context.  
     Now do the normal gimplification.  
     Gimplify condition.  
         For -O0 avoid this optimization if the COND_EXPR and GOTO_EXPR
         have different locations, otherwise we end up with incorrect
         location information on the branches.  
         For -O0 avoid this optimization if the COND_EXPR and GOTO_EXPR
         have different locations, otherwise we end up with incorrect
         location information on the branches.  
         For if (...) {} else { code; } put label_true after
         the else block.  
             For if (...) { code; } else {} or
             if (...) { code; } else goto label; or
             if (...) { code; return; } else { ... }
             label_cont isn't needed.  
                 GIMPLE_COND's are very low level; they have embedded
                 gotos.  This particular embedded goto should not be marked
                 with the location of the original COND_EXPR, as it would
                 correspond to the COND_EXPR's condition, not the ELSE or the
                 THEN arms.  To avoid marking it with the wrong location, flag
                 it as "no location".  
         Both arms are empty; replace the COND_EXPR with its predicate.  

Referenced by gimplify_omp_workshare().

static enum gimplify_status gimplify_conversion ( )
   *EXPR_P is a NOP_EXPR or CONVERT_EXPR.  Remove it and/or other conversions
   underneath as appropriate.  
     Then strip away all but the outermost conversion.  
     And remove the outermost conversion if it's useless.  
     If we still have a conversion at the toplevel,
     then canonicalize some constructs.  
         If a NOP conversion is changing the type of a COMPONENT_REF
         expression, then canonicalize its type now in order to expose more
         redundant conversions.  
         If a NOP conversion is changing a pointer to array of foo
         to a pointer to foo, embed that change in the ADDR_EXPR.  
     If we have a conversion to a non-register type force the
     use of a VIEW_CONVERT_EXPR instead.  
static enum gimplify_status gimplify_decl_expr ( )
   Gimplify a DECL_EXPR node *STMT_P by making any necessary allocation
   and initialization explicit.  
     ??? DECL_ORIGINAL_TYPE is streamed for LTO so it needs to be gimplified
     in case its size expressions contain problematic nodes like CALL_EXPR.  
         Some front ends do not explicitly declare all anonymous
         artificial variables.  We compensate here by declaring the
         variables, though it would be better if the front ends would
         explicitly declare them.  
               We must still examine initializers for static variables
               as they may contain a label address.  

References tree_int_cst_compare().

static enum gimplify_status gimplify_exit_expr ( )
   Gimplify an EXIT_EXPR by converting to a GOTO_EXPR inside a COND_EXPR.
   This also involves building a label to jump to and communicating it to
   gimplify_loop_expr through gimplify_ctxp->exit_label.  
enum gimplify_status gimplify_expr ( tree expr_p,
gimple_seq pre_p,
gimple_seq post_p,
bool(*)(tree gimple_test_f,
fallback_t  fallback 
   Convert the GENERIC expression tree *EXPR_P to GIMPLE.  If the
   expression produces a value to be used as an operand inside a GIMPLE
   statement, the value will be stored back in *EXPR_P.  This value will
   be a tree of class tcc_declaration, tcc_constant, tcc_reference or
   an SSA_NAME.  The corresponding sequence of GIMPLE statements is
   emitted in PRE_P and POST_P.

   Additionally, this process may overwrite parts of the input
   expression during gimplification.  Ideally, it should be
   possible to do non-destructive gimplification.

   EXPR_P points to the GENERIC expression to convert to GIMPLE.  If
      the expression needs to evaluate to a value to be used as
      an operand in a GIMPLE statement, this value will be stored in
      *EXPR_P on exit.  This happens when the caller specifies one
      of fb_lvalue or fb_rvalue fallback flags.

   PRE_P will contain the sequence of GIMPLE statements corresponding
       to the evaluation of EXPR and all the side-effects that must
       be executed before the main expression.  On exit, the last
       statement of PRE_P is the core statement being gimplified.  For
       instance, when gimplifying 'if (++a)' the last statement in
       PRE_P will be 'if (t.1)' where t.1 is the result of
       pre-incrementing 'a'.

   POST_P will contain the sequence of GIMPLE statements corresponding
       to the evaluation of all the side-effects that must be executed
       after the main expression.  If this is NULL, the post
       side-effects are stored at the end of PRE_P.

       The reason why the output is split in two is to handle post
       side-effects explicitly.  In some cases, an expression may have
       inner and outer post side-effects which need to be emitted in
       an order different from the one given by the recursive
       traversal.  For instance, for the expression (*p--)++ the post
       side-effects of '--' must actually occur *after* the post
       side-effects of '++'.  However, gimplification will first visit
       the inner expression, so if a separate POST sequence was not
       used, the resulting sequence would be:

            1   t.1 = *p
            2   p = p - 1
            3   t.2 = t.1 + 1
            4   *p = t.2

       However, the post-decrement operation in line #2 must not be
       evaluated until after the store to *p at line #4, so the
       correct sequence should be:

            1   t.1 = *p
            2   t.2 = t.1 + 1
            3   *p = t.2
            4   p = p - 1

       So, by specifying a separate post queue, it is possible
       to emit the post side-effects in the correct order.
       If POST_P is NULL, an internal queue will be used.  Before
       returning to the caller, the sequence POST_P is appended to
       the main output sequence PRE_P.

   GIMPLE_TEST_F points to a function that takes a tree T and
       returns nonzero if T is in the GIMPLE form requested by the
       caller.  The GIMPLE predicates are in gimple.c.

   FALLBACK tells the function what sort of a temporary we want if
       gimplification cannot produce an expression that complies with

       fb_none means that no temporary should be generated
       fb_rvalue means that an rvalue is OK to generate
       fb_lvalue means that an lvalue is OK to generate
       fb_either means that either is OK, but an lvalue is preferable.
       fb_mayfail means that gimplification may fail (in which case
       GS_ERROR will be returned)

   The return value is either GS_ERROR or GS_ALL_DONE, since this
   function iterates until EXPR is completely gimplified or an error
     If we are gimplifying a top-level statement, PRE_P must be valid.  
     Consistency checks.  
         We should have recognized the GIMPLE_TEST_F predicate to
         know what kind of fallback to use in case a temporary is
         needed to hold the value or address of *EXPR_P.  
     We used to check the predicate here and return immediately if it
     succeeds.  This is wrong; the design is for gimplification to be
     idempotent, and for the predicates to only test for valid forms, not
     whether they are fully simplified.  
     Remember the last statements added to PRE_P and POST_P.  Every
     new statement added by the gimplification helpers needs to be
     annotated with location information.  To centralize the
     responsibility, we remember the last statement that had been
     added to both queues before gimplifying *EXPR_P.  If
     gimplification produces new statements in PRE_P and POST_P, those
     statements will be annotated with the same location information
     as *EXPR_P.  
     Loop over the specific gimplifiers until the toplevel node
     remains the same.  
         Strip away as many useless type conversions as possible
         at the toplevel.  
         Remember the expr.  
         Die, die, die, my darling.  
         Do any language-specific gimplification.  
         Make sure that all the cases set 'ret' appropriately.  
             First deal with the special cases.  
             C99 code may assign to an array in a structure value of a
             conditional expression, and this has undefined behavior
             only on execution, so create a temporary if an lvalue is
             If errors are seen, then just process it as a CALL_EXPR.  
             C99 code may assign to an array in a structure returned
             from a function, and this has undefined behavior only on
             execution, so create a temporary if an lvalue is
               Preserve the original type of the expression and the
               source location of the outer expression.  
               The parsers are careful to generate TRUTH_NOT_EXPR
               only with operands that are always zero or one.
               We do not fold here but handle the only interesting case
               manually, as fold may re-introduce the TRUTH_NOT_EXPR.  
                 Just strip a conversion to void (or in void context) and
                 try again.  
             unary_expr: ... | '(' cast ')' val | ...  
           We arrive here through the various re-gimplifcation paths.  
             First try re-folding the whole thing.  
             Avoid re-gimplifying the address operand if it is already
             in suitable form.  Re-gimplifying would mark the address
             operand addressable.  Always gimplify when not in SSA form
             as we still may have to gimplify decls with value-exprs.  
           Constants need not be gimplified.  
             If we require an lvalue, such as for ADDR_EXPR, retain the
             CONST_DECL node.  Otherwise the decl is replaceable by its
             ??? Should be == fb_lvalue, but ADDR_EXPR passes fb_either.  
             If the target is not LABEL, then it is a computed jump
             and the target needs to be gimplified.  
             Don't reduce this in place; let gimplify_init_constructor work its
             magic.  Buf if we're just elaborating this for side effects, just
             gimplify any element that has side-effects.  
             C99 code may assign to an array in a constructed
             structure or union, and this has undefined behavior only
             on execution, so create a temporary if an lvalue is
             The following are special cases that are not handled by the
             original GIMPLE grammar.  
             SAVE_EXPR nodes are converted into a GIMPLE identifier and
               TMR_STEP and TMR_OFFSET are always integer constants.  
             This should have been stripped above.  
               Calls to destructors are generated automatically in FINALLY/CATCH
               block. They should have location as UNKNOWN_LOCATION. However,
               gimplify_call_expr will reset these call stmts to input_location
               if it finds stmt's location is unknown. To prevent resetting for
               destructors, we set the input_location to unknown.
               Note that this only affects the destructor calls in FINALLY/CATCH
               block, and will automatically reset to its original value by the
               end of gimplify_expr.  
               Don't create bogus GIMPLE_TRY with empty cleanup.  
             We get here when taking the address of a label.  We mark
             the label as "forced"; meaning it can never be removed and
             it is a potential target for any computed goto.  
             When within an OpenMP context, notice uses of variables.  
             Allow callbacks into the gimplifier during optimization.  
             Boolified binary truth expressions are semantically equivalent
             to bitwise binary expressions.  Canonicalize them to the
             bitwise variant.  
               Now make sure that operands have compatible type to
               expression's new_type.  
               Continue classified as tcc_binary.  
             Classified as tcc_expression.  
               Convert &X + CST to invariant &MEM[&X, CST].  Do this
               after gimplifying operands - this is similar to how
               it would be folding all gimplified stmts on creation
               to have them canonicalized, which is what we eventually
               should do anyway.  
                 Handle comparison of objects of non scalar mode aggregates
                 with a call to memcmp.  It would be nice to only have to do
                 this for variable-sized objects, but then we'd have to allow
                 the same nest of reference nodes we allow for MODIFY_EXPR and
                 that's too complex.

                 Compare scalar mode aggregates as scalar mode values.  Using
                 memcmp for them would be very inefficient at best, and is
                 plain wrong if bitfields are involved.  
                     Vector comparisons need no boolification.  
               If *EXPR_P does not need to be special-cased, handle it
               according to its class.  
     If we encountered an error_mark somewhere nested inside, either
     stub out the statement or propagate the error back out.  
     This was only valid as a return value from the langhook, which
     we handled.  Make sure it doesn't escape from any other context.  
         We aren't looking for a value, and we don't have a valid
         statement.  If it doesn't have side-effects, throw it away.  
             This is probably a _REF that contains something nested that
             has side effects.  Recurse through the operands to find it.  
                  Anything else with side-effects must be converted to
                  a valid statement before we get here.  
             Historically, the compiler has treated a bare reference
             to a non-BLKmode volatile lvalue as forcing a load.  
             Normally, we do not want to create a temporary for a
             TREE_ADDRESSABLE type because such a type should not be
             copied by bitwise-assignment.  However, we make an
             exception here, as all we are doing here is ensuring that
             we read the bytes that make up the type.  We use
             create_tmp_var_raw because create_tmp_var will abort when
             given a TREE_ADDRESSABLE type.  
           We can't do anything useful with a volatile reference to
           an incomplete type, so just throw it away.  Likewise for
           a BLKmode type, since any implicit inner load should
           already have been turned into an explicit one by the
           gimplification process.  
     If we are gimplifying at the statement level, we're done.  Tack
     everything together and return.  
         Since *EXPR_P has been converted into a GIMPLE tuple, clear
         it out for GC to reclaim it.  
         The result of gimplifying *EXPR_P is going to be the last few
         statements in *PRE_P and *POST_P.  Add location information
         to all the statements that were added by the gimplification
         These expressions should already be in gimple IR form.  
     Otherwise we're gimplifying a subexpression, so the resulting
     value is interesting.  If it's a valid operand that matches
     GIMPLE_TEST_F, we're done. Unless we are handling some
     post-effects internally; if that's the case, we need to copy into
     a temporary before adding the post-effects to POST_P.  
     Otherwise, we need to create a new temporary for the gimplified
     We can't return an lvalue if we have an internal postqueue.  The
     object the lvalue refers to would (probably) be modified by the
     postqueue; we need to copy the value out first, which means an
         An lvalue will do.  Take the address of the expression, store it
         in a temporary, and replace the expression with an INDIRECT_REF of
         that temporary.  
         An rvalue will do.  Assign the gimplified expression into a
         new temporary TMP and replace the original expression with
         TMP.  First, make sure that the expression has a type so that
         it can be assigned into a temporary.  
         If this is an asm statement, and the user asked for the
         impossible, don't die.  Fail and let gimplify_asm_expr
         issue an error.  
     Make sure the temporary matches our predicate.  

References eval(), gimple_build_try(), gimple_seq_add_seq(), gimple_seq_empty_p(), gimple_set_location(), GIMPLE_TRY_CATCH, GIMPLE_TRY_FINALLY, gimple_try_set_catch_is_cleanup(), gimplify_and_add(), gimplify_seq_add_stmt(), GS_ALL_DONE, and input_location.

Referenced by lookup_tmp_var().

void gimplify_function_tree ( )
   Entry point to the gimplification pass.  FNDECL is the FUNCTION_DECL
   node for the function we want to gimplify.

   Return the sequence of GIMPLE statements corresponding to the body
   of FNDECL.  
         Preliminarily mark non-addressed complex variables as eligible
         for promotion to gimple registers.  We'll transform their uses
         as we find them.  
     The tree body of the function is no longer needed, replace it
     with the new GIMPLE body.  
     If we're instrumenting function entry/exit, then prepend the call to
     the entry hook and wrap the whole function in a TRY_FINALLY_EXPR to
     catch the exit hook.  
     ??? Add some way to ignore exceptions for this TFE.  
         Clear the block for BIND, since it is no longer directly inside
         the function, but within a try block.  
         Replace the current function body with the body
         wrapped in the try/finally TF.  
static enum gimplify_status gimplify_init_constructor ( tree expr_p,
gimple_seq pre_p,
gimple_seq post_p,
bool  want_value,
bool  notify_temp_creation 
   A subroutine of gimplify_modify_expr.  Break out elements of a
   CONSTRUCTOR used as an initializer into separate MODIFY_EXPRs.

   Note that we still need to clear any elements that don't have explicit
   initializers, so if not all elements are initialized we keep the
   original MODIFY_EXPR, we just remove all of the constructor elements.

   If NOTIFY_TEMP_CREATION is true, do not gimplify, just return
   GS_ERROR if we would have to create a temporary when gimplifying
   this constructor.  Otherwise, return GS_OK.

   If NOTIFY_TEMP_CREATION is false, just do the gimplification.  
           Aggregate types must lower constructors to initialization of
           individual elements.  The exception is that a CONSTRUCTOR node
           with no elements indicates zero-initialization of the whole.  
           Fetch information about the constructor to direct later processing.
           We might want to make static versions of it in various cases, and
           can only do so if it known to be a valid constant initializer.  
           If a const aggregate variable is being initialized, then it
           should never be a lose to promote the variable to be static.  
               ??? C++ doesn't automatically append a .<number> to the
               assembler name, and even when it does, it looks at FE private
               data structures to figure out what that number should be,
               which are not set for this variable.  I suppose this is
               important for local statics for inline functions, which aren't
               "local" in the object file sense.  So in order to get a unique
               TU-local symbol, we must invoke the lhd version now.  
           If there are "lots" of initialized elements, even discounting
           those that are not address constants (and thus *must* be
           computed at runtime), then partition the constructor into
           constant and non-constant parts.  Block copy the constant
           parts in, then generate code for the non-constant parts.  
           TODO.  There's code in cp/typeck.c to do this.  
             store_constructor will ignore the clearing of variable-sized
             objects.  Initializers for such objects must explicitly set
             every field that needs to be set.  
             If the constructor isn't complete, clear the whole object

             ??? This ought not to be needed.  For any element not present
             in the initializer, we should simply set them to zero.  Except
             we'd need to *find* the elements that are not present, and that
             requires trickery to avoid quadratic compile-time behavior in
             large cases or excessive memory use in small cases.  
             If there are "lots" of zeros, it's more efficient to clear
             the memory and then set the nonzero elements.  
           If there are "lots" of initialized elements, and all of them
           are valid address constants, then the entire initializer can
           be dropped to memory, and then memcpy'd out.  Don't do this
           for sparse arrays, though, as it's more efficient to follow
           the standard CONSTRUCTOR behavior of memset followed by
           individual element initialization.  Also don't do this for small
           all-zero initializers (which aren't big enough to merit
           clearing), and don't try to make bitwise copies of
           TREE_ADDRESSABLE types.

           We cannot apply such transformation when compiling chkp static
           initializer because creation of initializer image in the memory
           will require static initialization of bounds for it.  It should
           result in another gimplification of similar initializer and we
           may fall into infinite loop.  
               ??? We can still get unbounded array types, at least
               from the C++ front end.  This seems wrong, but attempt
               to work around it for now.  
               Find the maximum alignment we can assume for the object.  
               ??? Make use of DECL_OFFSET_ALIGN.  
               Do a block move either if the size is so small as to make
               each individual move a sub-unit move on average, or if it
               is so large as to make individual moves inefficient.  
                   This is no longer an assignment of a CONSTRUCTOR, but
                   we still may have processing to do on the LHS.  So
                   pretend we didn't do anything here to let that happen.  
           If the target is volatile, we have non-zero elements and more than
           one field to assign, initialize the target from a temporary.  
           If there are nonzero elements and if needed, pre-evaluate to capture
           elements overlapping with the lhs into temporaries.  We must do this
           before clearing to fetch the values before they are zeroed-out.  
               Zap the CONSTRUCTOR element list, which simplifies this case.
               Note that we still have to gimplify, in order to handle the
               case of variable sized types.  Avoid shared tree structures.  
           If we have not block cleared the object, or if there are nonzero
           elements in the constructor, add assignments to the individual
           scalar fields of the object.  
           Extract the real and imaginary parts out of the ctor.  
           Complex types have either COMPLEX_CST or COMPLEX_EXPR to
           represent creation of a complex value.  
           Go ahead and simplify constant constructors to VECTOR_CST.  
               Even when ctor is constant, it might contain non-*_CST
               elements, such as addresses or trapping values like
               1.0/0.0 - 1.0/0.0.  Such expressions don't belong
               in VECTOR_CST nodes.  
               Don't reduce an initializer constant even if we can't
               make a VECTOR_CST.  It won't do anything for us, and it'll
               prevent us from representing it as a single constant.  
           Vector types use CONSTRUCTOR all the way through gimple
          compilation as a general initializer.  
         So how did we get a CONSTRUCTOR for a scalar type?  
         If we have gimplified both sides of the initializer but have
         not emitted an assignment, do so now.  

References GS_OK.

static void gimplify_init_ctor_eval ( tree  object,
vec< constructor_elt, va_gc > *  elts,
gimple_seq pre_p,
bool  cleared 
   A subroutine of gimplify_init_ctor_eval.  Create a loop for
   a RANGE_EXPR in a CONSTRUCTOR for an array.

      var = lower;
      object[var] = value;
      if (var == upper)
        goto loop_exit;
      var = var + 1;
      goto loop_entry;

   We increment var _after_ the loop exit check because we might otherwise
   fail if upper == TYPE_MAX_VALUE (type for upper).

   Note that we never have to deal with SAVE_EXPRs here, because this has
   already been taken care of for us, in gimplify_init_ctor_preeval().  
   A subroutine of gimplify_init_constructor.  Generate individual
   MODIFY_EXPRs for a CONSTRUCTOR.  OBJECT is the LHS against which the
   assignments should happen.  ELTS is the CONSTRUCTOR_ELTS of the
   CONSTRUCTOR.  CLEARED is true if the entire LHS object has been
   zeroed first.  
         NULL values are created above for gimplification errors.  
         ??? Here's to hoping the front end fills in all of the indices,
         so we don't have to figure out what's missing ourselves.  
         Skip zero-sized fields, unless value has side-effects.  This can
         happen with calls to functions returning a zero-sized type, which
         we shouldn't discard.  As a number of downstream passes don't
         expect sets of zero-sized fields, we rely on the gimplification of
         the MODIFY_EXPR we make below to drop the assignment statement.  
         If we have a RANGE_EXPR, we have to build a loop to assign the
         whole range.  
             If the lower bound is equal to upper, just treat it as if
             upper was the index.  
             Do not use bitsizetype for ARRAY_REF indices.  

References can_move_by_pieces(), force_labels_r(), GS_ERROR, GS_UNHANDLED, HOST_WIDE_INT, int_size_in_bytes(), tree_output_constant_def(), and useless_type_conversion_p().

static void gimplify_init_ctor_eval_range ( tree  object,
tree  lower,
tree  upper,
tree  value,
tree  array_elt_type,
gimple_seq pre_p,
bool  cleared 
     Create and initialize the index variable.  
     Add the loop entry label.  
     Build the reference.  
     If we are a constructor, just call gimplify_init_ctor_eval to do
     the store.  Otherwise just assign value to the reference.  
       NB we might have to call ourself recursively through
       gimplify_init_ctor_eval if the value is a constructor.  
     We exit the loop when the index var is equal to the upper bound.  
     Otherwise, increment the index var...  
     ...and jump back to the loop entry.  
     Add the loop exit label.  

Referenced by gimplify_modify_expr_to_memset().

static void gimplify_init_ctor_preeval ( tree expr_p,
gimple_seq pre_p,
gimple_seq post_p,
struct gimplify_init_ctor_preeval_data data 
   A subroutine of gimplify_init_constructor.  Pre-evaluate EXPR,
   force values that overlap with the lhs (as described by *DATA)
   into temporaries.  
     If the value is constant, then there's nothing to pre-evaluate.  
         Ensure it does not have side effects, it might contain a reference to
         the object we're initializing.  
     If the type has non-trivial constructors, we can't pre-evaluate.  
     Recurse for nested constructors.  
     If this is a variable sized type, we must remember the size.  
     Gimplify the constructor element to something appropriate for the rhs
     of a MODIFY_EXPR.  Given that we know the LHS is an aggregate, we know
     the gimplifier will consider this a store to memory.  Doing this
     gimplification now means that we won't have to deal with complicated
     language-specific trees, nor trees like SAVE_EXPR that can induce
     exponential search behavior.  
     If we gimplified to a bare decl, we can be sure that it doesn't overlap
     with the lhs, since "a = { .x=a }" doesn't make sense.  This will
     always be true for all scalars, since is_gimple_mem_rhs insists on a
     temporary variable for them.  
     If this is of variable size, we have no choice but to assume it doesn't
     overlap since we can't make a temporary for it.  
     Otherwise, we must search for overlap ...  
     ... and if found, force the value into a temporary.  
static tree gimplify_init_ctor_preeval_1 ( )
     If we find the base object, obviously we have overlap.  
     If the constructor component is indirect, determine if we have a
     potential overlap with the lhs.  The only bits of information we
     have to go on at this point are addressability and alias sets.  
     If the constructor component is a call, determine if it can hide a
     potential overlap with the lhs through an INDIRECT_REF like above.
     ??? Ugh - this is completely broken.  In fact this whole analysis
     doesn't look conservative.  

References ggc_free(), and gimplify_and_add().

static enum gimplify_status gimplify_loop_expr ( )
   Gimplify a LOOP_EXPR.  Normally this just involves gimplifying the body
   and replacing the LOOP_EXPR with goto, but if the loop contains an
   EXIT_EXPR, we need to append a label for it to jump to.  
static enum gimplify_status gimplify_modify_expr ( tree expr_p,
gimple_seq pre_p,
gimple_seq post_p,
bool  want_value 
   Gimplify the MODIFY_EXPR node pointed to by EXPR_P.

              : varname '=' rhs
              | '*' ID '=' rhs

    PRE_P points to the list where side effects that must happen before
        *EXPR_P should be stored.

    POST_P points to the list where side effects that must happen after
        *EXPR_P should be stored.

    WANT_VALUE is nonzero iff we want to use the value of this expression
        in another expression.  
     Trying to simplify a clobber using normal logic doesn't work,
     so handle it here.  
     Insert pointer conversions required by the middle-end that are not
     required by the frontend.  This fixes middle-end type checking for
     for example gcc.dg/redecl-6.c.  
     See if any simplifications can be done based on what the RHS is.  
     For zero sized types only gimplify the left hand side and right hand
     side as statements and throw away the assignment.  Do this after
     gimplify_modify_expr_rhs so we handle TARGET_EXPRs of addressable
     types properly.  
     If the value being copied is of variable width, compute the length
     of the copy into a WITH_SIZE_EXPR.   Note that we need to do this
     before gimplifying any of the operands so that we can resolve any
     PLACEHOLDER_EXPRs in the size.  Also note that the RTL expander uses
     the size of the expression to be copied, not of the destination, so
     that is what we must do here.  
     As a special case, we have to temporarily allow for assignments
     with a CALL_EXPR on the RHS.  Since in GIMPLE a function call is
     a toplevel statement, when gimplifying the GENERIC expression
     MODIFY_EXPR <a, CALL_EXPR <foo>>, we cannot create the tuple

     Instead, we need to create the tuple GIMPLE_CALL <a, foo>.  To
     prevent gimplify_expr from trying to create a new temporary for
     foo's LHS, we tell it that it should only gimplify until it
     reaches the CALL_EXPR.  On return from gimplify_expr, the newly
     created GIMPLE_CALL <foo> will be the last statement in *PRE_P
     and all we need to do here is set 'a' to be its LHS.  
     Now see if the above changed *from_p to something we handle specially.  
     If we've got a variable sized assignment between two lvalues (i.e. does
     not involve a call), then we can make things a bit more straightforward
     by converting the assignment to memcpy or memset.  
     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.  
     Try to alleviate the effects of the gimplification creating artificial
     temporaries (see for example is_gimple_reg_rhs) on the debug info.  
         Since the RHS is a CALL_EXPR, we need to create a GIMPLE_CALL
         instead of a GIMPLE_ASSIGN.  
         We should have got an SSA name from the start.  
     Don't fold stmts inside of target construct.  We'll do it
     during omplower pass instead.  
static enum gimplify_status gimplify_modify_expr_complex_part ( tree expr_p,
gimple_seq pre_p,
bool  want_value 
   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

   IMPORTANT NOTE: This promotion is performed by introducing a load of the
   other, unmodified part of the complex object just before the total store.
   As a consequence, if the object is still uninitialized, an undefined value
   will be loaded into a register, which may result in a spurious exception
   if the register is floating-point and the value happens to be a signaling
   NaN for example.  Then the fully-fledged complex operations lowering pass
   followed by a DCE pass are necessary in order to fix things up.  

References fold_convert_loc(), GS_OK, and useless_type_conversion_p().

static enum gimplify_status gimplify_modify_expr_rhs ( tree expr_p,
tree from_p,
tree to_p,
gimple_seq pre_p,
gimple_seq post_p,
bool  want_value 
   Subroutine of gimplify_modify_expr to do simplifications of
   MODIFY_EXPRs based on the code of the RHS.  We loop for as long as
   something changes.  
             If we're assigning from a read-only variable initialized with
             a constructor, do the direct assignment from the constructor,
             but only if neither source nor target are volatile since this
             latter assignment might end up being done on a per-field basis.  
                 Move the constructor into the RHS.  
                 Let's see if gimplify_init_constructor will need to put
                 it in memory.  
                     If so, revert the change.  
               If we have code like

             *(const A*)(A*)&x

             where the type of "x" is a (possibly cv-qualified variant
             of "A"), treat the entire expression as identical to "x".
             This kind of code arises in C++ when an object is bound
             to a const reference, and if "x" is a TARGET_EXPR we want
             to take advantage of the optimization below.  
               If we are initializing something from a TARGET_EXPR, strip the
               TARGET_EXPR and initialize it directly, if possible.  This can't
               be done if the initializer is void, since that implies that the
               temporary is set in some non-trivial way.

               ??? What about code that pulls out the temp and uses it
               elsewhere? I think that such code never uses the TARGET_EXPR as
               an initializer.  If I'm wrong, we'll die because the temp won't
               have any RTL.  In that case, I guess we'll need to replace
               references somehow.  
             Remove any COMPOUND_EXPR in the RHS so the following cases will be
             If we already made some changes, let the front end have a
             crack at this before we break it down.  
             If we're initializing from a CONSTRUCTOR, break this into
             individual MODIFY_EXPRs.  
             If we're assigning to a non-register type, push the assignment
             down into the branches.  This is mandatory for ADDRESSABLE types,
             since we cannot generate temporaries for such, but it saves a
             copy in other cases as well.  
                 This code should mirror the code in gimplify_cond_expr. 
             For calls that return in memory, give *to_p as the CALL_EXPR's
             return slot so that we don't generate a temporary.  
                   If we need a temporary, *to_p isn't accurate.  
                 It's OK to use the return slot directly unless it's an NRV. 
                   Don't force regs into memory.  
                   It's OK to use the target directly if it's being
                   Always use the target and thus RSO for variable-sized types.
                   GIMPLE cannot deal with a variable-sized assignment
                   embedded in a call statement.  
                   Don't use the original target if it's already addressable;
                   if its address escapes, and the called function uses the
                   NRV optimization, a conforming program could see *to_p
                   change before the called function returns; see c++/19317.
                   When optimizing, the return_slot pass marks more functions
                   as safe after we have escape info.  
             Likewise for calls that return an aggregate of non-constant size,
             since we would not be able to generate a temporary at all.  
                 We don't change ret in this case because the
                 WITH_SIZE_EXPR might have been added in
                 gimplify_modify_expr, so returning GS_OK would lead to an
                 infinite loop.  
             If we're initializing from a container, push the initialization
             inside it.  
               struct T x = (struct T) { 0, 1, 2 } can be optimized
               into struct T x = { 0, 1, 2 } if the address of the
               compound literal has never been taken.  
static enum gimplify_status gimplify_modify_expr_to_memcpy ( tree expr_p,
tree  size,
bool  want_value,
gimple_seq seq_p 
   A subroutine of gimplify_modify_expr.  Replace a MODIFY_EXPR with
   a call to __builtin_memcpy.  
     Mark the RHS addressable.  Beware that it may not be possible to do so
     directly if a temporary has been created by the gimplification.  
         tmp = memcpy() 
static enum gimplify_status gimplify_modify_expr_to_memset ( tree expr_p,
tree  size,
bool  want_value,
gimple_seq seq_p 
   A subroutine of gimplify_modify_expr.  Replace a MODIFY_EXPR with
   a call to __builtin_memset.  In this case we know that the RHS is
   a CONSTRUCTOR with an empty element list.  
     Assert our assumptions, to abort instead of producing wrong code
     silently if they are not met.  Beware that the RHS CONSTRUCTOR might
     not be immediately exposed.  
     Now proceed.  
         tmp = memset() 

References gimplify_init_ctor_eval_range(), initializer_zerop(), simple_cst_equal(), unshare_expr(), and zero_sized_field_decl().

static enum gimplify_status gimplify_omp_atomic ( )
   Gimplify an OMP_ATOMIC statement.  
static enum gimplify_status gimplify_omp_for ( )
   Gimplify the gross structure of an OMP_FOR statement.  
     Handle OMP_FOR_INIT.  
         Make sure the iteration variable is private.  
           Do this only on innermost construct for combined ones.  
         If DECL is not a gimple register, create a temporary variable to act
         as an iteration counter.  This is valid, since DECL cannot be
         modified in the body of the loop.  
         Handle OMP_FOR_COND.  
         Handle OMP_FOR_INCR.  
static void gimplify_omp_parallel ( )
   Gimplify the contents of an OMP_PARALLEL statement.  This involves
   gimplification of the body, as well as scanning the body for used
   variables.  We need to do this scan now, because variable-sized
   decls will be decomposed during gimplification.  
static void gimplify_omp_target_update ( )
   Gimplify the gross structure of OpenMP target update construct.  
static void gimplify_omp_task ( )
   Gimplify the contents of an OMP_TASK statement.  This involves
   gimplification of the body, as well as scanning the body for used
   variables.  We need to do this scan now, because variable-sized
   decls will be decomposed during gimplification.  

References types_compatible_p().

void gimplify_one_sizepos ( )
   A subroutine of gimplify_type_sizes to make sure that *EXPR_P,
   a size or position, has had all of its SAVE_EXPRs evaluated.
   We add any required statements to *STMT_P.  
     We don't do anything if the value isn't there, is constant, or contains
     A PLACEHOLDER_EXPR.  We also don't want to do anything if it's already
     a VAR_DECL.  If it's a VAR_DECL from another function, the gimplifier
     will want to replace it with a new variable, but that will cause problems
     if this type is from outside the function.  It's OK to have that here.  

References targetm.

static enum gimplify_status gimplify_pure_cond_expr ( )
   Given a conditional expression *EXPR_P without side effects, gimplify
   its operands.  New statements are inserted to PRE_P.  
     We need to handle && and || specially, as their gimplification
     creates pure cond_expr, thus leading to an infinite cycle otherwise.  
static enum gimplify_status gimplify_return_expr ( )
   Gimplify a RETURN_EXPR.  If the expression to be returned is not a
   GIMPLE value, it is assigned to a new temporary and the statement is
   re-written to return the temporary.

   PRE_P points to the sequence where side effects that must happen before
   STMT should be stored.  
     Implicit _Cilk_sync must be inserted right before any return statement 
     if there is a _Cilk_spawn in the function.  If the user has provided a 
     _Cilk_sync, the optimizer should remove this duplicate one.  
         See through a return by reference.  
     If aggregate_value_p is true, then we can return the bare RESULT_DECL.
     Recall that aggregate_value_p is FALSE for any aggregate type that is
     returned in registers.  If we're returning values in registers, then
     we don't want to extend the lifetime of the RESULT_DECL, particularly
     across another call.  In addition, for those aggregates for which
     hard_function_value generates a PARALLEL, we'll die during normal
     expansion of structure assignments; there's special code in expand_return
     to handle this case that does not exist in expand_expr.  
             Note that we don't use gimplify_vla_decl because the RESULT_DECL
             should be effectively allocated by the caller, i.e. all calls to
             this function must be subject to the Return Slot Optimization.  
         ??? With complex control flow (usually involving abnormal edges),
         we can wind up warning about an uninitialized value for this.  Due
         to how this variable is constructed and initialized, this is never
         true.  Give up and never warn.  
     Smash the lhs of the MODIFY_EXPR to the temporary we plan to use.
     Then gimplify the whole thing.  

References build_call_expr(), build_pointer_type(), builtin_decl_explicit(), create_tmp_var(), get_name(), gimplify_and_add(), gimplify_one_sizepos(), and gimplify_ctx::save_stack.

static enum gimplify_status gimplify_save_expr ( )
   Gimplify a SAVE_EXPR node.  EXPR_P points to the expression to
   gimplify.  After gimplification, EXPR_P will point to a new temporary
   that holds the original value of the SAVE_EXPR node.

   PRE_P points to the list where side effects that must happen before
   *EXPR_P should be stored.  
     If the SAVE_EXPR has not been resolved, then evaluate it once.  
         The operand may be a void-valued expression such as SAVE_EXPRs
         generated by the Java frontend for class initialization.  It is
         being executed only for its side-effects.  
static enum gimplify_status gimplify_scalar_mode_aggregate_compare ( )
   Gimplify a comparison between two aggregate objects of integral scalar
   mode as a comparison between the bitwise equivalent scalar values.  
static void gimplify_scan_omp_clauses ( tree list_p,
gimple_seq pre_p,
enum omp_region_type  region_type 
   Scan the OpenMP clauses in *LIST_P, installing mappings into a new
   and previous omp contexts.  
             Fall through.  
enum gimplify_status gimplify_self_mod_expr ( tree expr_p,
gimple_seq pre_p,
gimple_seq post_p,
bool  want_value,
tree  arith_type 
    Gimplify the self modifying expression pointed to by EXPR_P
    (++, --, +=, -=).

    PRE_P points to the list where side effects that must happen before
        *EXPR_P should be stored.

    POST_P points to the list where side effects that must happen after
        *EXPR_P should be stored.

    WANT_VALUE is nonzero iff we want to use the value of this expression
        in another expression.

    ARITH_TYPE is the type the computation should be performed in.  
     Prefix or postfix?  
       Faster to treat as prefix if result is not used.  
     For postfix, make sure the inner expression's post side effects
     are executed after side effects from this expression.  
     Add or subtract?  
     Gimplify the LHS into a GIMPLE lvalue.  
     Extract the operands to the arithmetic operation.  
     For postfix operator, we evaluate the LHS to an rvalue and then use
     that as the result value and in the postqueue operation.  
     For POINTERs increment, use POINTER_PLUS_EXPR.  

Referenced by gimplify_omp_workshare().

static void gimplify_seq_add_seq ( )
   Append sequence SRC to the end of sequence *DST_P.  If *DST_P is
   NULL, a new sequence is allocated.   This function is
   similar to gimple_seq_add_seq, but does not scan the operands.
   During gimplification, we need to manipulate statement sequences
   before the def/use vectors have been constructed.  
static void gimplify_seq_add_stmt ( )
   Shorter alias name for the above function for use in gimplify.c

References si.

Referenced by build_stack_save_restore(), gimplify_expr(), and gimplify_vla_decl().

static enum gimplify_status gimplify_statement_list ( )
   Gimplify a statement list onto a sequence.  These may be created either
   by an enlightened front-end, or by shortcut_cond_expr.  
bool gimplify_stmt ( )
   Gimplification of expression trees.  
   Gimplify an expression which appears at statement context.  The
   corresponding GIMPLE statements are added to *SEQ_P.  If *SEQ_P is
   NULL, a new sequence is allocated.

   Return true if we actually added a statement to the queue.  
static enum gimplify_status gimplify_switch_expr ( )
   Gimplify a SWITCH_EXPR, and collect the vector of labels it can
   branch to.  
         If someone can be bothered to fill in the labels, they can
         be bothered to null out the body too.  
         Save old labels, get new ones from body, then restore the old
         labels.  Save all the things from the switch body to append after.  

References build_qualified_type(), get_unwidened(), type(), and useless_type_conversion_p().

static enum gimplify_status gimplify_target_expr ( )
   Gimplify a TARGET_EXPR which doesn't appear on the rhs of an INIT_EXPR.  
         TARGET_EXPR temps aren't part of the enclosing block, so add it
         to the temps list.  Handle also variable length TARGET_EXPRs.  
         If TARGET_EXPR_INITIAL is void, then the mere evaluation of the
         expression is supposed to initialize the slot.  
             PR c++/28266 Make sure this is expanded only once. 
         If needed, push the cleanup for the temp.  
         Add a clobber for the temporary going out of scope, like
         Only expand this once.  
       We should have expanded this before.  
static enum gimplify_status gimplify_transaction ( )
   Gimplify a TRANSACTION_EXPR.  This involves gimplification of the
   body, and adding some EH bits.  
     Wrap the transaction body in a BIND_EXPR so we have a context
     where to put decls for OpenMP.  
void gimplify_type_sizes ( )
   Look through TYPE for variable-sized objects and gimplify each such
   size that we find.  Add to LIST_P any statements generated.  
     We first do the main variant, then copy into any other variants.  
     Avoid infinite recursion.  
         These types may not have declarations, so handle them here.  
         Ensure VLA bounds aren't removed, for -O0 they should be variables
         with assigned stack slots, for -O1+ -g they should be tracked
         by VTA.  
           We used to recurse on the pointed-to type here, which turned out to
           be incorrect because its definition might refer to variables not
           yet initialized at this point if a forward declaration is involved.

           It was actually useful for anonymous pointed-to types to ensure
           that the sizes evaluation dominates every possible later use of the
           values.  Restricting to such types here would be safe since there
           is no possible forward declaration around, but would introduce an
           undesirable middle-end semantic to anonymity.  We then defer to
           front-ends the responsibility of ensuring that the sizes are
           evaluated both early and late enough, e.g. by attaching artificial
           type declarations to the tree.  
enum gimplify_status gimplify_va_arg_expr ( )
   Gimplify __builtin_va_arg, aka VA_ARG_EXPR, which is not really a
   builtin function, but a very special sort of operator.  
     Verify that valist is of the proper type.  
     Generate a diagnostic for requesting data of a type that cannot
     be passed through `...' due to type promotion at the call site.  
         Unfortunately, this is merely undefined, rather than a constraint
         violation, so we cannot make this an error.  If this call is never
         executed, the program is still strictly conforming.  
         We can, however, treat "undefined" any way we please.
         Call abort to encourage the user to fix the program.  
         Before the abort, allow the evaluation of the va_list
         expression to exit or longjmp.  
         This is dead code, but go ahead and finish so that the
         mode of the result comes out right.  
         Make it easier for the backends by protecting the valist argument
         from multiple evaluations.  
             For this case, the backends will be expecting a pointer to
             TREE_TYPE (abi), but it's possible we've
             actually been given an array (an actual TARGET_FN_ABI_VA_LIST).
             So fix it.  
           FIXME: Once most targets are converted we should merely
           assert this is non-null.  
static enum gimplify_status gimplify_var_or_parm_decl ( )
   Gimplify a VAR_DECL or PARM_DECL.  Return GS_OK if we expanded a
   DECL_VALUE_EXPR, and it's worth re-examining things.  
     ??? If this is a local variable, and it has not been seen in any
     outer BIND_EXPR, then it's probably the result of a duplicate
     declaration, for which we've already issued an error.  It would
     be really nice if the front end wouldn't leak these at all.
     Currently the only known culprit is C++ destructors, as seen
     in g++.old-deja/g++.jason/binding.C.  
     When within an OpenMP context, notice uses of variables.  
     If the decl is an alias for another expression, substitute it now.  
         For referenced nonlocal VLAs add a decl for debugging purposes
         to the current function.  
static enum gimplify_status gimplify_variable_sized_compare ( )
   Gimplify a comparison between two variable-sized objects.  Do this
   with a call to BUILT_IN_MEMCMP.  

References error(), and GS_ERROR.

static void gimplify_vla_decl ( )
   Gimplify a variable-length array DECL.  
     This is a variable-sized decl.  Simplify its size and mark it
     for deferred expansion.  
     Don't mess with a DECL_VALUE_EXPR set by the front-end.  
     All occurrences of this decl in final gimplified code will be
     replaced by indirection.  Setting DECL_VALUE_EXPR does two
     things: First, it lets the rest of the gimplifier know what
     replacement to use.  Second, it lets the debug info know
     where to find the value.  
     The call has been built for a variable-sized object.  
     Indicate that we need to restore the stack level when the
     enclosing BIND_EXPR is exited.  

References create_artificial_label(), gimplify_ctx::exit_label, gimple_build_goto(), gimple_build_label(), gimplify_and_add(), gimplify_seq_add_stmt(), and GS_ALL_DONE.

static bool goa_lhs_expr_p ( )
   A subroutine of gimplify_omp_atomic.  The front end is supposed to have
   stabilized the lhs of the atomic operation as *ADDR.  Return true if
   EXPR is this stabilized form.  
     Also include casts to other type variants.  The C front end is fond
     of adding these for e.g. volatile variables.  This is like
     STRIP_TYPE_NOPS but includes the main variant lookup.  
static int goa_stabilize_expr ( tree expr_p,
gimple_seq pre_p,
tree  lhs_addr,
tree  lhs_var 
   Walk *EXPR_P and replace appearances of *LHS_ADDR with LHS_VAR.  If an
   expression does not involve the lhs, evaluate it into a temporary.
   Return 1 if the lhs appeared as a subexpression, 0 if it did not,
   or -1 if an error was encountered.  
             Break out any preevaluations from cp_build_modify_expr.  
static tree internal_get_tmp_var ( tree  val,
gimple_seq pre_p,
gimple_seq post_p,
bool  is_formal 
   Helper for get_formal_tmp_var and get_initialized_tmp_var.  
     Notice that we explicitly allow VAL to be a CALL_EXPR so that we
     can create an INIT_EXPR and convert it into a GIMPLE_CALL below.  
     gimplify_modify_expr might want to reduce this further.  
static bool is_gimple_mem_rhs ( )
   Returns true iff T is a valid RHS for an assignment to an un-renamed
   LHS, or for a call argument.  
     If we're dealing with a renamable type, either source or dest must be
     a renamed variable.  
static bool is_gimple_mem_rhs_or_call ( )
   Return true if T is a valid memory RHS or a CALL_EXPR.  Note that
   this predicate should only be used during gimplification.  See the
   rationale for this in gimplify_modify_expr.  
     If we're dealing with a renamable type, either source or dest must be
     a renamed variable.  
static bool is_gimple_reg_rhs ( )
   Returns true iff T is a valid RHS for an assignment to a renamed
   user -- or front-end generated artificial -- variable.  

References is_gimple_reg_type().

static bool is_gimple_reg_rhs_or_call ( )
   Return true if T is a CALL_EXPR or an expression that can be
   assigned to a temporary.  Note that this predicate should only be
   used during gimplification.  See the rationale for this in

Referenced by lookup_tmp_var().

static bool is_gimple_stmt ( )
   Return true if T looks like a valid GIMPLE statement.  
         The only valid NOP_EXPR is the empty statement.  
         These are only valid if they're void.  
         These are always void.  
         These are valid regardless of their type.  
static tree lookup_tmp_var ( )
   Create a temporary to hold the value of VAL.  If IS_FORMAL, try to reuse
   an existing expression temporary.  
     If not optimizing, never really reuse a temporary.  local-alloc
     won't allocate any variable that is used in more than one basic
     block, which means it will go into memory, causing much extra
     work in reload and final and poorer code generation, outweighing
     the extra memory allocation here.  

References fb_rvalue, ggc_free(), gimplify_and_add(), gimplify_expr(), gimplify_ctx::into_ssa, is_gimple_reg_rhs_or_call(), is_gimple_reg_type(), make_ssa_name(), and unshare_expr().

void mark_addressable ( )
   Mark X addressable.  Unlike the langhook we expect X to be in gimple
   form and we don't do any syntax checking.  
     Also mark the artificial SSA_NAME that points to the partition of X.  

Referenced by create_iv(), gimplify_omp_workshare(), initialize_argument_information(), instrument_builtin_call(), and move_by_pieces_1().

static void maybe_with_size_expr ( )
   If *EXPR_P has a variable sized type, wrap it in a WITH_SIZE_EXPR.  
     If we've already wrapped this or the type is error_mark_node, we can't do
     If the size isn't known or is a constant, we have nothing to do.  
     Otherwise, make a WITH_SIZE_EXPR.  

References build_call_array_loc(), BUILT_IN_NORMAL, and get_callee_fndecl().

static tree mostly_copy_tree_r ( )
   This page contains routines to unshare tree nodes, i.e. to duplicate tree
   nodes that are referenced more than once in GENERIC functions.  This is
   necessary because gimplification (translation into GIMPLE) is performed
   by modifying tree nodes in-place, so gimplication of a shared node in a
   first context could generate an invalid GIMPLE form in a second context.

   This is achieved with a simple mark/copy/unmark algorithm that walks the
   GENERIC representation top-down, marks nodes with TREE_VISITED the first
   time it encounters them, duplicates them if they already have TREE_VISITED
   set, and finally removes the TREE_VISITED marks it has set.

   The algorithm works only at the function level, i.e. it generates a GENERIC
   representation of a function with no nodes shared within the function when
   passed a GENERIC function (except for nodes that are allowed to be shared).

   At the global level, it is also necessary to unshare tree nodes that are
   referenced in more than one function, for the same aforementioned reason.
   This requires some cooperation from the front-end.  There are 2 strategies:

     1. Manual unsharing.  The front-end needs to call unshare_expr on every
        expression that might end up being shared across functions.

     2. Deep unsharing.  This is an extension of regular unsharing.  Instead
        of calling unshare_expr on expressions that might be shared across
        functions, the front-end pre-marks them with TREE_VISITED.  This will
        ensure that they are unshared on the first reference within functions
        when the regular unsharing algorithm runs.  The counterpart is that
        this algorithm must look deeper than for manual unsharing, which is
        specified by LANG_HOOKS_DEEP_UNSHARING.

  If there are only few specific cases of node sharing across functions, it is
  probably easier for a front-end to unshare the expressions manually.  On the
  contrary, if the expressions generated at the global level are as widespread
  as expressions generated within functions, deep unsharing is very likely the
  way to go.  
   Similar to copy_tree_r but do not copy SAVE_EXPR or TARGET_EXPR nodes.
   These nodes model computations that must be done once.  If we were to
   unshare something like SAVE_EXPR(i++), the gimplification process would
   create wrong code.  However, if DATA is non-null, it must hold a pointer
   set that is used to unshare the subtrees of these nodes.  
     Do not copy SAVE_EXPR, TARGET_EXPR or BIND_EXPR nodes themselves, but
     copy their subtrees if we can make sure to do it only once.  
     Stop at types, decls, constants like copy_tree_r.  
              We can't do anything sensible with a BLOCK used as an
              expression, but we also can't just die when we see it
              because of non-expression uses.  So we avert our eyes
              and cross our fingers.  Silly Java.  
     Cope with the statement expression extension.  
     Leave the bulk of the work to copy_tree_r itself.  

Referenced by copy_if_shared().

static struct gimplify_omp_ctx* new_omp_context ( )
   Create a new omp construct that deals with variable remapping.  

References pointer_set_destroy(), gimplify_omp_ctx::privatized_types, and gimplify_omp_ctx::variables.

static void omp_add_variable ( struct gimplify_omp_ctx ,
tree  ,
unsigned  int 
static void omp_add_variable ( )
   Add an entry for DECL in the OpenMP context CTX with FLAGS.  
     Never elide decls whose type has TREE_ADDRESSABLE set.  This means
     there are constructors involved somewhere.  
         We shouldn't be re-adding the decl with the same data
         sharing class.  
         The only combination of data sharing classes we should see is
     When adding a variable-sized variable, we have to handle all sorts
     of additional bits of data: the pointer replacement variable, and
     the parameters of the type.  
         Add the pointer replacement variable as PRIVATE if the variable
         replacement is private, else FIRSTPRIVATE since we'll need the
         address of the original variable either for SHARED, or for the
         copy into or out of the context.  
         Add all of the variable and type parameters (which should have
         been gimplified to a formal temporary) as FIRSTPRIVATE.  
         The variable-sized variable itself is never SHARED, only some form
         of PRIVATE.  The sharing would take place via the pointer variable
         which we remapped above.  
         We're going to make use of the TYPE_SIZE_UNIT at least in the
         alloca statement we generate for the variable, so make sure it
         is available.  This isn't automatically needed for the SHARED
         case, since we won't be allocating local storage then.
         For local variables TYPE_SIZE_UNIT might not be gimplified yet,
         in this case omp_notice_variable will be called later
         on when it is gimplified.  
         Similar to the direct variable sized case above, we'll need the
         size of references being privatized.  
static bool omp_check_private ( )
   Return true if DECL is private within a parallel region
   that binds to the current construct's context or in parallel
   region's REDUCTION clause.  
                    References might be private, but might be shared too.  

References gimplify_omp_ctx::outer_context, and gimplify_omp_ctx::variables.

static void omp_firstprivatize_type_sizes ( )
   Similarly for each of the type sizes of TYPE.  
void omp_firstprivatize_variable ( )
   Add FIRSTPRIVATE entries for DECL in the OpenMP the surrounding parallels
   to CTX.  If entries already exist, force them to be some flavor of private.
   If there is no enclosing parallel, do nothing.  
static bool omp_notice_threadprivate_variable ( struct gimplify_omp_ctx ctx,
tree  decl,
tree  decl2 
   Notice a threadprivate variable DECL used in OpenMP context CTX.
   This just prints out diagnostics about threadprivate variable uses
   in untied tasks.  If DECL2 is non-NULL, prevent this warning
   on that variable.  
static bool omp_notice_variable ( struct gimplify_omp_ctx ,
tree  ,
static bool omp_notice_variable ( )
   Record the fact that DECL was used within the OpenMP context CTX.
   IN_CODE is true when real code uses DECL, and false when we should
   merely emit default(none) errors.  Return true if DECL is going to
   be remapped and thus DECL shouldn't be gimplified into its
   DECL_VALUE_EXPR (if any).  
     Threadprivate variables are predetermined.  
         ??? Some compiler-generated variables (like SAVE_EXPRs) could be
         remapped firstprivate instead of shared.  To some extent this is
         addressed in omp_firstprivatize_type_sizes, but not effectively.  
             decl will be either GOVD_FIRSTPRIVATE or GOVD_SHARED.  
     If nothing changed, there's nothing left to do.  
     If the variable is private in the current context, then we don't
     need to propagate anything to an outer context.  
static tree optimize_compound_literals_in_ctor ( )
   Optimize embedded COMPOUND_LITERAL_EXPRs within a CONSTRUCTOR,
   return a new CONSTRUCTOR if something changed.  

References build_vector_from_ctor(), and initializer_constant_valid_p().

void pop_gimplify_context ( )
   Tear down a context for the gimplifier.  If BODY is non-null, then
   put the temporaries into the outer BIND_EXPR.  Otherwise, put them
   in the local_decls.

   BODY is not a sequence, but the first tuple in a sequence.  
static void prepare_gimple_addressable ( )
   Prepare the node pointed to by EXPR_P, an is_gimple_addressable expression,
   to be marked addressable.

   We cannot rely on such an expression being directly markable if a temporary
   has been created by the gimplification.  In this case, we create another
   temporary and initialize it with a copy, which will become a store after we
   mark it addressable.  This can happen if the front-end passed us something
   that it could not mark addressable yet, like a Fortran pass-by-reference
   parameter (int) floatvar.  
void preprocess_case_label_vec_for_gimple ( vec< tree labels,
tree  index_type,
tree default_casep 
   Prepare a vector of case labels to be used in a GIMPLE_SWITCH statement.

   LABELS is a vector that contains all case labels to look at.

   INDEX_TYPE is the type of the switch index expression.  Case labels
   in LABELS are discarded if their values are not in the value range
   covered by INDEX_TYPE.  The remaining case label values are folded

   If a default case exists in LABELS, it is removed from LABELS and
   returned in DEFAULT_CASEP.  If no default case exists, but the
   case labels already cover the whole range of INDEX_TYPE, a default
   case is returned pointing to one of the existing case labels.
   Otherwise DEFAULT_CASEP is set to NULL_TREE.

   DEFAULT_CASEP may be NULL, in which case the above comment doesn't
   apply and no action is taken regardless of whether a default case is
   found or not.  
             This is a non-default case label, i.e. it has a value.

             See if the case label is reachable within the range of
             the index type.  Remove out-of-range case values.  Turn
             case ranges into a canonical form (high > low strictly)
             and convert the case label values to the index type.

             NB: The type of gimple_switch_index() may be the promoted
             type, but the case labels retain the original type.  
                 This is a case range.  Discard empty ranges.
                 If the bounds or the range are equal, turn this
                 into a simple (one-value) case.  
                 If the simple case value is unreachable, ignore it.  
                 If the entire case range is unreachable, ignore it.  
                     If the lower bound is less than the index type's
                     minimum value, truncate the range bounds.  
                     If the upper bound is greater than the index type's
                     maximum value, truncate the range bounds.  
                     We may have folded a case range to a one-value case.  
             The default case must be passed separately to the
             gimple_build_switch routine.  But if DEFAULT_CASEP
             is NULL, we do not remove the default case (it would
             be completely lost).  
         If the switch has no default label, add one, so that we jump
         around the switch body.  If the labels already cover the whole
         range of the switch index_type, add the default label pointing
         to one of the existing labels.  

References build_case_label(), len, and tree_int_cst_equal().

static tree prune_expr_location ( )
   Worker for unshare_expr_without_location.  
void push_gimplify_context ( )
   Set up a context for the gimplifier.  

References gimplify_ctx::bind_expr_stack, gimplify_ctxp, and gimplify_ctx::prev_context.

static void remove_suffix ( )
   Strip off a legitimate source ending from the input string NAME of
   length LEN.  Rather than having to know the names used by all of
   our front ends, we strip off an ending of a period followed by
   up to five characters.  (Java uses ".class".)  

References clean_symbol_name(), and strlen().

gimple_predicate rhs_predicate_for ( )
   Return the appropriate RHS predicate for this LHS.  
static tree shortcut_cond_expr ( )
   Given a conditional expression EXPR with short-circuit boolean
   predicates using TRUTH_ANDIF_EXPR or TRUTH_ORIF_EXPR, break the
   predicate apart into the equivalent sequence of conditionals.  
     First do simple transformations.  
         If there is no 'else', turn
           if (a && b) then c
           if (a) if (b) then c.  
             Keep the original source location on the first 'if'.  
             Set the source location of the && on the second 'if'.  
         If there is no 'then', turn
           if (a || b); else d
           if (a); else if (b); else d.  
             Keep the original source location on the first 'if'.  
             Set the source location of the || on the second 'if'.  
     If we're done, great.  
     Otherwise we need to mess with gotos.  Change
       if (a) c; else d;
       if (a); else goto no;
       c; goto end;
       no: d; end:
     and recursively gimplify the condition.  
     If our arms just jump somewhere, hijack those labels so we don't
     generate jumps to jumps.  
     If we aren't hijacking a label for the 'then' branch, it falls through.  
     The 'else' branch also needs a label if it contains interesting code.  
     If there was nothing else in our arms, just forward the label(s).  
     If our last subexpression already has a terminal label, reuse it.  
     If we don't care about jumping to the 'else' branch, jump to the end
     if the condition is false.  
     We only want to emit these labels if we aren't hijacking them.  
     We only emit the jump over the else clause if we have to--if the
     then clause may fall through.  Otherwise we can wind up with a
     useless jump and a useless label at the end of gimplified code,
     which will cause us to think that this conditional as a whole
     falls through even if it doesn't.  If we then inline a function
     which ends with such a condition, that can cause us to issue an
     inappropriate warning about control reaching the end of a
     non-void function.  

References gimple_boolify().

static tree shortcut_cond_r ( tree  pred,
tree true_label_p,
tree false_label_p,
location_t  locus 
   Handle shortcut semantics in the predicate operand of a COND_EXPR by
   rewriting it into multiple COND_EXPRs, and possibly GOTO_EXPRs.

   TRUE_LABEL_P and FALSE_LABEL_P point to the labels to jump to if the
   condition is true or false, respectively.  If null, we should generate
   our own to skip over the evaluation of this specific expression.

   LOCUS is the source location of the COND_EXPR.

   This function is the tree equivalent of do_jump.

   shortcut_cond_r should only be called by shortcut_cond_expr.  
     OK, it's not a simple case; we need to pull apart the COND_EXPR to
     retain the shortcut semantics.  Just insert the gotos here;
     shortcut_cond_expr will append the real blocks later.  
         Turn if (a && b) into

         if (a); else goto no;
         if (b) goto yes; else goto no;
         Keep the original source location on the first 'if'.  
         Set the source location of the && on the second 'if'.  
         Turn if (a || b) into

         if (a) goto yes;
         if (b) goto yes; else goto no;
         Keep the original source location on the first 'if'.  
         Set the source location of the || on the second 'if'.  
         As long as we're messing with gotos, turn if (a ? b : c) into
         if (a)
           if (b) goto yes; else goto no;
           if (c) goto yes; else goto no;

         Don't do this if one of the arms has void type, which can happen
         in C++ when the arm is throw.  
         Keep the original source location on the first 'if'.  Set the source
         location of the ? on the second 'if'.  
static bool should_carry_location_p ( )
   Determine whether to assign a location to the statement GS.  
     Don't emit a line note for a label.  We particularly don't want to
     emit one for the break label, since it doesn't actually correspond
     to the beginning of the loop/switch.  
void sort_case_labels ( )
   Sort the case labels in LABEL_VEC in place in ascending order.  
static int splay_tree_compare_decl_uid ( )
   A stable comparison routine for use with splay trees and DECLs.  
static void unmark_visited ( )
   Unmark the visited trees rooted at *TP.  
static tree unmark_visited_r ( )
   Callback for walk_tree to unmark the visited trees rooted at *TP.
   Subtrees are walked until the first unvisited node is encountered.  
     If this node has been visited, unmark it and keep looking.  
     Otherwise, don't look any deeper.  
static void unshare_body ( )
   Unshare all the trees in the body of FNDECL, as well as in the bodies of
   any nested functions.  
     If the language requires deep unsharing, we need a pointer set to make
     sure we don't repeatedly unshare subtrees of unshareable nodes.  
tree unshare_expr_without_location ( )
   Similar to unshare_expr but also prune all expression locations
   from EXPR.  

Referenced by free_temp_arrays(), and ipa_set_jf_known_type().

static void unvisit_body ( )
   Likewise, but mark all trees as not visited.  

References tsi_end_p(), tsi_last(), and tsi_stmt_ptr().

tree voidify_wrapper_expr ( )
   WRAPPER is a code such as BIND_EXPR or CLEANUP_POINT_EXPR which can both
   contain statements and have a value.  Assign its value to a temporary
   and give it void_type_node.  Return the temporary, or NULL_TREE if
   WRAPPER was already void.  
         Set p to point to the body of the wrapper.  Loop until we find
         something that isn't a wrapper.  
                 For a BIND_EXPR, the body is operand 1.  
                 Advance to the last statement.  Set all container types to
                 Assume that any tree upon which voidify_wrapper_expr is
                 directly called is a wrapper, and that its body is op0.  
             The wrapper is on the RHS of an assignment that we're pushing
static bool zero_sized_field_decl ( )
   Return true if FDECL is accessing a field that is zero sized.  

Referenced by gimplify_modify_expr_to_memset().

static bool zero_sized_type ( )
   Return true if TYPE is zero sized.  

Variable Documentation

struct gimplify_ctx* gimplify_ctxp

Referenced by push_gimplify_context().

struct gimplify_omp_ctx* gimplify_omp_ctxp
struct pointer_set_t* nonlocal_vlas
   Nonlocal VLAs seen in the current function.  
unsigned int tmp_var_id_num
   Create a new temporary name with PREFIX.  Return an identifier.