1/* Definitions for code generation pass of GNU compiler.
2 Copyright (C) 1987-2017 Free Software Foundation, Inc.
3
4This file is part of GCC.
5
6GCC is free software; you can redistribute it and/or modify it under
7the terms of the GNU General Public License as published by the Free
8Software Foundation; either version 3, or (at your option) any later
9version.
10
11GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12WARRANTY; without even the implied warranty of MERCHANTABILITY or
13FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14for more details.
15
16You should have received a copy of the GNU General Public License
17along with GCC; see the file COPYING3. If not see
18<http://www.gnu.org/licenses/>. */
19
20#ifndef GCC_EXPR_H
21#define GCC_EXPR_H
22
23/* This is the 4th arg to `expand_expr'.
24 EXPAND_STACK_PARM means we are possibly expanding a call param onto
25 the stack.
26 EXPAND_SUM means it is ok to return a PLUS rtx or MULT rtx.
27 EXPAND_INITIALIZER is similar but also record any labels on forced_labels.
28 EXPAND_CONST_ADDRESS means it is ok to return a MEM whose address
29 is a constant that is not a legitimate address.
30 EXPAND_WRITE means we are only going to write to the resulting rtx.
31 EXPAND_MEMORY means we are interested in a memory result, even if
32 the memory is constant and we could have propagated a constant value,
33 or the memory is unaligned on a STRICT_ALIGNMENT target. */
34enum expand_modifier {EXPAND_NORMAL = 0, EXPAND_STACK_PARM, EXPAND_SUM,
35 EXPAND_CONST_ADDRESS, EXPAND_INITIALIZER, EXPAND_WRITE,
36 EXPAND_MEMORY};
37
38/* Prevent the compiler from deferring stack pops. See
39 inhibit_defer_pop for more information. */
40#define NO_DEFER_POP (inhibit_defer_pop += 1)
41
42/* Allow the compiler to defer stack pops. See inhibit_defer_pop for
43 more information. */
44#define OK_DEFER_POP (inhibit_defer_pop -= 1)
45
46/* This structure is used to pass around information about exploded
47 unary, binary and trinary expressions between expand_expr_real_1 and
48 friends. */
49typedef struct separate_ops
50{
51 enum tree_code code;
52 location_t location;
53 tree type;
54 tree op0, op1, op2;
55} *sepops;
56
57/* This is run during target initialization to set up which modes can be
58 used directly in memory and to initialize the block move optab. */
59extern void init_expr_target (void);
60
61/* This is run at the start of compiling a function. */
62extern void init_expr (void);
63
64/* Emit some rtl insns to move data between rtx's, converting machine modes.
65 Both modes must be floating or both fixed. */
66extern void convert_move (rtx, rtx, int);
67
68/* Convert an rtx to specified machine mode and return the result. */
69extern rtx convert_to_mode (machine_mode, rtx, int);
70
71/* Convert an rtx to MODE from OLDMODE and return the result. */
72extern rtx convert_modes (machine_mode, machine_mode, rtx, int);
73
74/* Expand a call to memcpy or memmove or memcmp, and return the result. */
75extern rtx emit_block_op_via_libcall (enum built_in_function, rtx, rtx, rtx,
76 bool);
77
78static inline rtx
79emit_block_copy_via_libcall (rtx dst, rtx src, rtx size, bool tailcall = false)
80{
81 return emit_block_op_via_libcall (BUILT_IN_MEMCPY, dst, src, size, tailcall);
82}
83
84static inline rtx
85emit_block_move_via_libcall (rtx dst, rtx src, rtx size, bool tailcall = false)
86{
87 return emit_block_op_via_libcall (BUILT_IN_MEMMOVE, dst, src, size, tailcall);
88}
89
90static inline rtx
91emit_block_comp_via_libcall (rtx dst, rtx src, rtx size, bool tailcall = false)
92{
93 return emit_block_op_via_libcall (BUILT_IN_MEMCMP, dst, src, size, tailcall);
94}
95
96/* Emit code to move a block Y to a block X. */
97enum block_op_methods
98{
99 BLOCK_OP_NORMAL,
100 BLOCK_OP_NO_LIBCALL,
101 BLOCK_OP_CALL_PARM,
102 /* Like BLOCK_OP_NORMAL, but the libcall can be tail call optimized. */
103 BLOCK_OP_TAILCALL
104};
105
106typedef rtx (*by_pieces_constfn) (void *, HOST_WIDE_INT, scalar_int_mode);
107
108extern rtx emit_block_move (rtx, rtx, rtx, enum block_op_methods);
109extern rtx emit_block_move_hints (rtx, rtx, rtx, enum block_op_methods,
110 unsigned int, HOST_WIDE_INT,
111 unsigned HOST_WIDE_INT,
112 unsigned HOST_WIDE_INT,
113 unsigned HOST_WIDE_INT);
114extern rtx emit_block_cmp_hints (rtx, rtx, rtx, tree, rtx, bool,
115 by_pieces_constfn, void *);
116extern bool emit_storent_insn (rtx to, rtx from);
117
118/* Copy all or part of a value X into registers starting at REGNO.
119 The number of registers to be filled is NREGS. */
120extern void move_block_to_reg (int, rtx, int, machine_mode);
121
122/* Copy all or part of a BLKmode value X out of registers starting at REGNO.
123 The number of registers to be filled is NREGS. */
124extern void move_block_from_reg (int, rtx, int);
125
126/* Generate a non-consecutive group of registers represented by a PARALLEL. */
127extern rtx gen_group_rtx (rtx);
128
129/* Load a BLKmode value into non-consecutive registers represented by a
130 PARALLEL. */
131extern void emit_group_load (rtx, rtx, tree, int);
132
133/* Similarly, but load into new temporaries. */
134extern rtx emit_group_load_into_temps (rtx, rtx, tree, int);
135
136/* Move a non-consecutive group of registers represented by a PARALLEL into
137 a non-consecutive group of registers represented by a PARALLEL. */
138extern void emit_group_move (rtx, rtx);
139
140/* Move a group of registers represented by a PARALLEL into pseudos. */
141extern rtx emit_group_move_into_temps (rtx);
142
143/* Store a BLKmode value from non-consecutive registers represented by a
144 PARALLEL. */
145extern void emit_group_store (rtx, rtx, tree, int);
146
147extern rtx maybe_emit_group_store (rtx, tree);
148
149/* Mark REG as holding a parameter for the next CALL_INSN.
150 Mode is TYPE_MODE of the non-promoted parameter, or VOIDmode. */
151extern void use_reg_mode (rtx *, rtx, machine_mode);
152extern void clobber_reg_mode (rtx *, rtx, machine_mode);
153
154extern rtx copy_blkmode_to_reg (machine_mode, tree);
155
156/* Mark REG as holding a parameter for the next CALL_INSN. */
157static inline void
158use_reg (rtx *fusage, rtx reg)
159{
160 use_reg_mode (fusage, reg, VOIDmode);
161}
162
163/* Mark REG as clobbered by the call with FUSAGE as CALL_INSN_FUNCTION_USAGE. */
164static inline void
165clobber_reg (rtx *fusage, rtx reg)
166{
167 clobber_reg_mode (fusage, reg, VOIDmode);
168}
169
170/* Mark NREGS consecutive regs, starting at REGNO, as holding parameters
171 for the next CALL_INSN. */
172extern void use_regs (rtx *, int, int);
173
174/* Mark a PARALLEL as holding a parameter for the next CALL_INSN. */
175extern void use_group_regs (rtx *, rtx);
176
177#ifdef GCC_INSN_CODES_H
178extern rtx expand_cmpstrn_or_cmpmem (insn_code, rtx, rtx, rtx, tree, rtx,
179 HOST_WIDE_INT);
180#endif
181
182/* Write zeros through the storage of OBJECT.
183 If OBJECT has BLKmode, SIZE is its length in bytes. */
184extern rtx clear_storage (rtx, rtx, enum block_op_methods);
185extern rtx clear_storage_hints (rtx, rtx, enum block_op_methods,
186 unsigned int, HOST_WIDE_INT,
187 unsigned HOST_WIDE_INT,
188 unsigned HOST_WIDE_INT,
189 unsigned HOST_WIDE_INT);
190/* The same, but always output an library call. */
191extern rtx set_storage_via_libcall (rtx, rtx, rtx, bool = false);
192
193/* Expand a setmem pattern; return true if successful. */
194extern bool set_storage_via_setmem (rtx, rtx, rtx, unsigned int,
195 unsigned int, HOST_WIDE_INT,
196 unsigned HOST_WIDE_INT,
197 unsigned HOST_WIDE_INT,
198 unsigned HOST_WIDE_INT);
199
200/* Return nonzero if it is desirable to store LEN bytes generated by
201 CONSTFUN with several move instructions by store_by_pieces
202 function. CONSTFUNDATA is a pointer which will be passed as argument
203 in every CONSTFUN call.
204 ALIGN is maximum alignment we can assume.
205 MEMSETP is true if this is a real memset/bzero, not a copy
206 of a const string. */
207extern int can_store_by_pieces (unsigned HOST_WIDE_INT,
208 by_pieces_constfn,
209 void *, unsigned int, bool);
210
211/* Generate several move instructions to store LEN bytes generated by
212 CONSTFUN to block TO. (A MEM rtx with BLKmode). CONSTFUNDATA is a
213 pointer which will be passed as argument in every CONSTFUN call.
214 ALIGN is maximum alignment we can assume.
215 MEMSETP is true if this is a real memset/bzero, not a copy.
216 Returns TO + LEN. */
217extern rtx store_by_pieces (rtx, unsigned HOST_WIDE_INT, by_pieces_constfn,
218 void *, unsigned int, bool, int);
219
220/* Emit insns to set X from Y. */
221extern rtx_insn *emit_move_insn (rtx, rtx);
222extern rtx_insn *gen_move_insn (rtx, rtx);
223
224/* Emit insns to set X from Y, with no frills. */
225extern rtx_insn *emit_move_insn_1 (rtx, rtx);
226
227extern rtx_insn *emit_move_complex_push (machine_mode, rtx, rtx);
228extern rtx_insn *emit_move_complex_parts (rtx, rtx);
229extern rtx read_complex_part (rtx, bool);
230extern void write_complex_part (rtx, rtx, bool);
231extern rtx read_complex_part (rtx, bool);
232extern rtx emit_move_resolve_push (machine_mode, rtx);
233
234/* Push a block of length SIZE (perhaps variable)
235 and return an rtx to address the beginning of the block. */
236extern rtx push_block (rtx, int, int);
237
238/* Generate code to push something onto the stack, given its mode and type. */
239extern bool emit_push_insn (rtx, machine_mode, tree, rtx, unsigned int,
240 int, rtx, int, rtx, rtx, int, rtx, bool);
241
242/* Extract the accessible bit-range from a COMPONENT_REF. */
243extern void get_bit_range (unsigned HOST_WIDE_INT *, unsigned HOST_WIDE_INT *,
244 tree, HOST_WIDE_INT *, tree *);
245
246/* Expand an assignment that stores the value of FROM into TO. */
247extern void expand_assignment (tree, tree, bool);
248
249/* Generate code for computing expression EXP,
250 and storing the value into TARGET.
251 If SUGGEST_REG is nonzero, copy the value through a register
252 and return that register, if that is possible. */
253extern rtx store_expr_with_bounds (tree, rtx, int, bool, bool, tree);
254extern rtx store_expr (tree, rtx, int, bool, bool);
255
256/* Given an rtx that may include add and multiply operations,
257 generate them as insns and return a pseudo-reg containing the value.
258 Useful after calling expand_expr with 1 as sum_ok. */
259extern rtx force_operand (rtx, rtx);
260
261/* Work horses for expand_expr. */
262extern rtx expand_expr_real (tree, rtx, machine_mode,
263 enum expand_modifier, rtx *, bool);
264extern rtx expand_expr_real_1 (tree, rtx, machine_mode,
265 enum expand_modifier, rtx *, bool);
266extern rtx expand_expr_real_2 (sepops, rtx, machine_mode,
267 enum expand_modifier);
268
269/* Generate code for computing expression EXP.
270 An rtx for the computed value is returned. The value is never null.
271 In the case of a void EXP, const0_rtx is returned. */
272static inline rtx
273expand_expr (tree exp, rtx target, machine_mode mode,
274 enum expand_modifier modifier)
275{
276 return expand_expr_real (exp, target, mode, modifier, NULL, false);
277}
278
279static inline rtx
280expand_normal (tree exp)
281{
282 return expand_expr_real (exp, NULL_RTX, VOIDmode, EXPAND_NORMAL, NULL, false);
283}
284
285
286/* Return the tree node and offset if a given argument corresponds to
287 a string constant. */
288extern tree string_constant (tree, tree *);
289
290/* Two different ways of generating switch statements. */
291extern int try_casesi (tree, tree, tree, tree, rtx, rtx, rtx, profile_probability);
292extern int try_tablejump (tree, tree, tree, tree, rtx, rtx, profile_probability);
293
294extern int safe_from_p (const_rtx, tree, int);
295
296/* Get the personality libfunc for a function decl. */
297rtx get_personality_function (tree);
298
299/* Determine whether the LEN bytes can be moved by using several move
300 instructions. Return nonzero if a call to move_by_pieces should
301 succeed. */
302extern bool can_move_by_pieces (unsigned HOST_WIDE_INT, unsigned int);
303
304extern unsigned HOST_WIDE_INT highest_pow2_factor (const_tree);
305
306extern bool categorize_ctor_elements (const_tree, HOST_WIDE_INT *,
307 HOST_WIDE_INT *, bool *);
308
309extern void expand_operands (tree, tree, rtx, rtx*, rtx*,
310 enum expand_modifier);
311
312/* rtl.h and tree.h were included. */
313/* Return an rtx for the size in bytes of the value of an expr. */
314extern rtx expr_size (tree);
315
316#endif /* GCC_EXPR_H */
317