gcc/gimple.def

   1 /* This file contains the definitions of the GIMPLE IR tuples used in GCC.
   2
   3    Copyright (C) 2007, 2008 Free Software Foundation, Inc.
   4    Contributed by Aldy Hernandez <aldyh@redhat.com>
   5
   6 This file is part of GCC.
   7
   8 GCC is free software; you can redistribute it and/or modify it under
   9 the terms of the GNU General Public License as published by the Free
  10 Software Foundation; either version 3, or (at your option) any later
  11 version.
  12
  13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16 for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GCC; see the file COPYING3.  If not see
  20 <http://www.gnu.org/licenses/>.  */
  21
  22 /* The format of this file is
  23    DEFGSCODE(GIMPLE_symbol, printable name, structure).
  24
  25    Where symbol is the enumeration name without the ``GIMPLE_''.
  26    The argument STRUCTURE is used to compute offsets into each of the
  27    tuple structures that contain operands.  Since vector operands
  28    are at different offsets depending on the particular structure
  29    used, these offsets are computed at compile time for efficient
  30    lookup at runtime.  See gimple_ops().
  31
  32    If a code does not use operand vectors, STRUCTURE should be NULL.  */
  33
  34 /* Error marker.  This is used in similar ways as ERROR_MARK in tree.def.  */
  35 DEFGSCODE(GIMPLE_ERROR_MARK, "gimple_error_mark", NULL)
  36
  37 /* IMPORTANT.  Do not rearrange the codes between GIMPLE_COND and
  38    GIMPLE_RETURN.  The ordering is exposed by gimple_has_ops calls.
  39    These are all the GIMPLE statements with register operands.  */
  40
  41 /* GIMPLE_COND <COND_CODE, OP1, OP2, TRUE_LABEL, FALSE_LABEL>
  42    represents the conditional jump:
  43
  44    if (OP1 COND_CODE OP2) goto TRUE_LABEL else goto FALSE_LABEL
  45
  46    COND_CODE is the tree code used as the comparison predicate.  It
  47    must be of class tcc_comparison.
  48
  49    OP1 and OP2 are the operands used in the comparison.  They must be
  50    accepted by is_gimple_operand.
  51
  52    TRUE_LABEL and FALSE_LABEL are the LABEL_DECL nodes used as the
  53    jump target for the comparison.  */
  54 DEFGSCODE(GIMPLE_COND, "gimple_cond", struct gimple_statement_with_ops)
  55
  56 /* GIMPLE_GOTO <TARGET> represents unconditional jumps.
  57    TARGET is a LABEL_DECL or an expression node for computed GOTOs.  */
  58 DEFGSCODE(GIMPLE_GOTO, "gimple_goto", struct gimple_statement_with_ops)
  59
  60 /* GIMPLE_LABEL <LABEL> represents label statements.  LABEL is a
  61    LABEL_DECL representing a jump target.  */
  62 DEFGSCODE(GIMPLE_LABEL, "gimple_label", struct gimple_statement_with_ops)
  63
  64 /* GIMPLE_SWITCH <INDEX, DEFAULT_LAB, LAB1, ..., LABN> represents the
  65    multiway branch:
  66
  67    switch (INDEX)
  68    {
  69      case LAB1: ...; break;
  70      ...
  71      case LABN: ...; break;
  72      default: ...
  73    }
  74
  75    INDEX is the variable evaluated to decide which label to jump to.
  76
  77    DEFAULT_LAB, LAB1 ... LABN are the tree nodes representing case labels.
  78    They must be CASE_LABEL_EXPR nodes.  */
  79 DEFGSCODE(GIMPLE_SWITCH, "gimple_switch", struct gimple_statement_with_ops)
  80
  81 /* GIMPLE_CHANGE_DYNAMIC_TYPE indicates a change in the dynamic type
  82    of a memory location.  This has no value and generates no
  83    executable code.  It is only used for type based alias analysis.
  84    This is generated by C++ placement new and it's a direct
  85    translation from CHANGE_DYNAMIC_TYPE_EXPR.  The first operand
  86    (gimple_cdt_new_type) is the new type.  The second operand
  87    (gimple_cdt_location) is the location (pointer) whose type is being
  88    changed.  */
  89 DEFGSCODE(GIMPLE_CHANGE_DYNAMIC_TYPE, "gimple_change_dynamic_type",
  90           struct gimple_statement_with_ops)
  91
  92 /* IMPORTANT.
  93
  94    Do not rearrange the codes between GIMPLE_ASSIGN and GIMPLE_RETURN.
  95    It's exposed by GIMPLE_RANGE_CHECK calls. These are all the GIMPLE
  96    statements with memory and register operands.  */
  97
  98 /* GIMPLE_ASSIGN <SUBCODE, LHS, RHS1[, RHS2]> represents the assignment
  99    statement
 100
 101    LHS = RHS1 SUBCODE RHS2.
 102
 103    SUBCODE is the tree code for the expression computed by the RHS of the
 104    assignment.  It must be one of the tree codes accepted by
 105    get_gimple_rhs_class.
 106
 107    LHS is the operand on the LHS of the assignment.  It must be a tree node
 108    accepted by is_gimple_operand.
 109
 110    RHS1 is the first operand on the RHS of the assignment. It must be a tree
 111    node accepted by is_gimple_operand.
 112
 113    RHS2 is the second operand on the RHS of the assignemnt. It must be a tree
 114    node accepted by is_gimple_operand.  This argument exists only if SUBCODE is
 115    of class GIMPLE_BINARY_RHS.  */
 116 DEFGSCODE(GIMPLE_ASSIGN, "gimple_assign",
 117           struct gimple_statement_with_memory_ops)
 118
 119 /* GIMPLE_ASM <STRING, I1, ..., IN, O1, ... OM, C1, ..., CP>
 120    represents inline assembly statements.
 121
 122    STRING is the string containing the assembly statements.
 123    I1 ... IN are the N input operands.
 124    O1 ... OM are the M output operands.
 125    C1 ... CP are the P clobber operands.  */
 126 DEFGSCODE(GIMPLE_ASM, "gimple_asm", struct gimple_statement_asm)
 127
 128 /* GIMPLE_CALL <FN, LHS, ARG1, ..., ARGN[, CHAIN]> represents function
 129    calls.
 130
 131    FN is the callee.  It must be accepted by is_gimple_call_addr.
 132
 133    LHS is the operand where the return value from FN is stored.  It may
 134    be NULL.
 135
 136    ARG1 ... ARGN are the arguments.  They must all be accepted by
 137    is_gimple_operand.
 138
 139     CHAIN is the optional static chain link for nested functions.  */
 140 DEFGSCODE(GIMPLE_CALL, "gimple_call",
 141           struct gimple_statement_with_memory_ops)
 142
 143 /* GIMPLE_RETURN <RETVAL> represents return statements.
 144
 145    RETVAL is the value to return or NULL.  If a value is returned it
 146    must be accepted by is_gimple_operand.  */
 147 DEFGSCODE(GIMPLE_RETURN, "gimple_return",
 148           struct gimple_statement_with_memory_ops)
 149
 150 /* GIMPLE_BIND <VARS, BLOCK, BODY> represents a lexical scope.
 151    VARS is the set of variables declared in that scope.
 152    BLOCK is the symbol binding block used for debug information.
 153    BODY is the sequence of statements in the scope.  */
 154 DEFGSCODE(GIMPLE_BIND, "gimple_bind", NULL)
 155
 156 /* GIMPLE_CATCH <TYPES, HANDLER> represents a typed exception handler.
 157    TYPES is the type (or list of types) handled.  HANDLER is the
 158    sequence of statements that handle these types.  */
 159 DEFGSCODE(GIMPLE_CATCH, "gimple_catch", NULL)
 160
 161 /* GIMPLE_EH_FILTER <TYPES, FAILURE> represents an exception
 162    specification.  TYPES is a list of allowed types and FAILURE is the
 163    sequence of statements to execute on failure.  */
 164 DEFGSCODE(GIMPLE_EH_FILTER, "gimple_eh_filter", NULL)
 165
 166 /* GIMPLE_PHI <RESULT, ARG1, ..., ARGN> represents the PHI node
 167
 168    RESULT = PHI <ARG1, ..., ARGN>
 169
 170    RESULT is the SSA name created by this PHI node.
 171
 172    ARG1 ... ARGN are the arguments to the PHI node.  N must be
 173    exactly the same as the number of incoming edges to the basic block
 174    holding the PHI node.  Every argument is either an SSA name or a
 175    tree node of class tcc_constant.  */
 176 DEFGSCODE(GIMPLE_PHI, "gimple_phi", NULL)
 177
 178 /* GIMPLE_RESX <REGION> resumes execution after an exception.
 179    REGION is the region number being left.  */
 180 DEFGSCODE(GIMPLE_RESX, "gimple_resx", NULL)
 181
 182 /* GIMPLE_TRY <TRY_KIND, EVAL, CLEANUP>
 183    represents a try/catch or a try/finally statement.
 184
 185    TRY_KIND is either GIMPLE_TRY_CATCH or GIMPLE_TRY_FINALLY.
 186
 187    EVAL is the sequence of statements to execute on entry to GIMPLE_TRY.
 188
 189    CLEANUP is the sequence of statements to execute according to
 190    TRY_KIND.  If TRY_KIND is GIMPLE_TRY_CATCH, CLEANUP is only exected
 191    if an exception is thrown during execution of EVAL.  If TRY_KIND is
 192    GIMPLE_TRY_FINALLY, CLEANUP is always executed after executing EVAL
 193    (regardless of whether EVAL finished normally, or jumped out or an
 194    exception was thrown).  */
 195 DEFGSCODE(GIMPLE_TRY, "gimple_try", NULL)
 196
 197 /* GIMPLE_NOP represents the "do nothing" statement.  */
 198 DEFGSCODE(GIMPLE_NOP, "gimple_nop", NULL)
 199
 200
 201 /* IMPORTANT.
 202
 203    Do not rearrange any of the GIMPLE_OMP_* codes.  This ordering is
 204    exposed by the range check in gimple_omp_subcode().  */
 205
 206
 207 /* Tuples used for lowering of OMP_ATOMIC.  Although the form of the OMP_ATOMIC
 208    expression is very simple (just in form mem op= expr), various implicit
 209    conversions may cause the expression to become more complex, so that it does
 210    not fit the gimple grammar very well.  To overcome this problem, OMP_ATOMIC
 211    is rewritten as a sequence of two codes in gimplification:
 212
 213    GIMPLE_OMP_LOAD (tmp, mem)
 214    val = some computations involving tmp;
 215    GIMPLE_OMP_STORE (val).  */
 216 DEFGSCODE(GIMPLE_OMP_ATOMIC_LOAD, "gimple_omp_atomic_load", NULL)
 217 DEFGSCODE(GIMPLE_OMP_ATOMIC_STORE, "gimple_omp_atomic_store", NULL)
 218
 219 /* GIMPLE_OMP_CONTINUE marks the location of the loop or sections
 220    iteration in partially lowered OpenMP code.  */
 221 DEFGSCODE(GIMPLE_OMP_CONTINUE, "gimple_omp_continue", NULL)
 222
 223 /* GIMPLE_OMP_CRITICAL <NAME, BODY> represents
 224
 225    #pragma omp critical [name]
 226
 227    NAME is the name given to the critical section.
 228    BODY is the sequence of statements that are inside the critical section.  */
 229 DEFGSCODE(GIMPLE_OMP_CRITICAL, "gimple_omp_critical", NULL)
 230
 231 /* GIMPLE_OMP_FOR <BODY, CLAUSES, INDEX, INITIAL, FINAL, COND, INCR, PRE_BODY>
 232    represents
 233
 234    PRE_BODY
 235    #pragma omp for [clause1 ... clauseN]
 236    for (INDEX = INITIAL; INDEX COND FINAL; INDEX {+=,-=} INCR)
 237    BODY
 238
 239    BODY is the loop body.
 240
 241    CLAUSES is the list of clauses.
 242
 243    INDEX must be an integer or pointer variable, which is implicitly thread
 244    private.  It must be accepted by is_gimple_operand.
 245
 246    INITIAL is the initial value given to INDEX. It must be
 247    accepted by is_gimple_operand.
 248
 249    FINAL is the final value that INDEX should take. It must
 250    be accepted by is_gimple_operand.
 251
 252    COND is the condition code for the controlling predicate.  It must
 253    be one of { <, >, <=, >= }
 254
 255    INCR is the loop index increment.  It must be tree node of type
 256    tcc_constant.
 257
 258    PRE_BODY is a landing pad filled by the gimplifier with things from
 259    INIT, COND, and INCR that are technically part of the OMP_FOR
 260    structured block, but are evaluated before the loop body begins.
 261
 262    INITIAL, FINAL and INCR are required to be loop invariant integer
 263    expressions that are evaluated without any synchronization.
 264    The evaluation order, frequency of evaluation and side-effects are
 265    unspecified by the standard.  */
 266 DEFGSCODE(GIMPLE_OMP_FOR, "gimple_omp_for", NULL)
 267
 268 /* GIMPLE_OMP_MASTER <BODY> represents #pragma omp master.
 269    BODY is the sequence of statements to execute in the master section.  */
 270 DEFGSCODE(GIMPLE_OMP_MASTER, "gimple_omp_master", NULL)
 271
 272 /* GIMPLE_OMP_ORDERED <BODY> represents #pragma omp ordered.
 273    BODY is the sequence of statements to execute in the ordered section.  */
 274 DEFGSCODE(GIMPLE_OMP_ORDERED, "gimple_omp_ordered", NULL)
 275
 276 /* GIMPLE_OMP_PARALLEL <BODY, CLAUSES, CHILD_FN, DATA_ARG> represents
 277
 278    #pragma omp parallel [CLAUSES]
 279    BODY
 280
 281    BODY is a the sequence of statements to be executed by all threads.
 282
 283    CLAUSES is a TREE_LIST node with all the clauses.
 284
 285    CHILD_FN is set when outlining the body of the parallel region.
 286    All the statements in BODY are moved into this newly created
 287    function when converting OMP constructs into low-GIMPLE.
 288
 289    DATA_ARG is a local variable in the parent function containing data
 290    to be shared with CHILD_FN.  This is used to implement all the data
 291    sharing clauses.  */
 292 DEFGSCODE(GIMPLE_OMP_PARALLEL, "gimple_omp_parallel", NULL)
 293
 294 /* GIMPLE_OMP_TASK <BODY, CLAUSES, CHILD_FN, DATA_ARG, COPY_FN,
 295                     ARG_SIZE, ARG_ALIGN> represents
 296
 297    #pragma omp task [CLAUSES]
 298    BODY
 299
 300    BODY is a the sequence of statements to be executed by all threads.
 301
 302    CLAUSES is a TREE_LIST node with all the clauses.
 303
 304    CHILD_FN is set when outlining the body of the explicit task region.
 305    All the statements in BODY are moved into this newly created
 306    function when converting OMP constructs into low-GIMPLE.
 307
 308    DATA_ARG is a local variable in the parent function containing data
 309    to be shared with CHILD_FN.  This is used to implement all the data
 310    sharing clauses.
 311
 312    COPY_FN is set when outlining the firstprivate var initialization.
 313    All the needed statements are emitted into the newly created
 314    function, or when only memcpy is needed, it is NULL.
 315
 316    ARG_SIZE and ARG_ALIGN are the size and alignment of the incoming
 317    data area allocated by GOMP_task and passed to CHILD_FN.  */
 318 DEFGSCODE(GIMPLE_OMP_TASK, "gimple_omp_task", NULL)
 319
 320 /* OMP_RETURN marks the end of an OpenMP directive.  */
 321 DEFGSCODE(GIMPLE_OMP_RETURN, "gimple_omp_return", NULL)
 322
 323 /* OMP_SECTION <BODY> represents #pragma omp section.
 324    BODY is the sequence of statements in the section body.  */
 325 DEFGSCODE(GIMPLE_OMP_SECTION, "gimple_omp_section", NULL)
 326
 327 /* OMP_SECTIONS <BODY, CLAUSES, CONTROL> represents #pragma omp sections.
 328
 329    BODY is the sequence of statements in the sections body.
 330    CLAUSES is a TREE_LIST node holding the list of associated clauses.
 331    CONTROL is a VAR_DECL used for deciding which of the sections
 332    to execute.  */
 333 DEFGSCODE(GIMPLE_OMP_SECTIONS, "gimple_omp_sections", NULL)
 334
 335 /* GIMPLE_OMP_SECTIONS_SWITCH is a marker placed immediately after
 336    OMP_SECTIONS.  It represents the GIMPLE_SWITCH used to decide which
 337    branch is taken.  */
 338 DEFGSCODE(GIMPLE_OMP_SECTIONS_SWITCH, "gimple_omp_sections_switch", NULL)
 339
 340 /* GIMPLE_OMP_SINGLE <BODY, CLAUSES> represents #pragma omp single
 341    BODY is the sequence of statements inside the single section.
 342    CLAUSES is a TREE_LIST node holding the associated clauses.  */
 343 DEFGSCODE(GIMPLE_OMP_SINGLE, "gimple_omp_single", NULL)
 344
 345 /* GIMPLE_PREDICT <PREDICT, OUTCOME> specifies a hint for branch prediction.
 346
 347    PREDICT is one of the predictors from predict.def.
 348
 349    OUTCOME is NOT_TAKEN or TAKEN.  */
 350 DEFGSCODE(GIMPLE_PREDICT, "gimple_predict", NULL)
 351
 352 /*  This node represents a cleanup expression.  It is ONLY USED INTERNALLY
 353     by the gimplifier as a placeholder for cleanups, and its uses will be
 354     cleaned up by the time gimplification is done.
 355
 356     This tuple should not exist outside of the gimplifier proper.  */
 357 DEFGSCODE(GIMPLE_WITH_CLEANUP_EXPR, "gimple_with_cleanup_expr", NULL)