xref: /netbsd-src/external/gpl3/gcc.old/dist/gcc/config/xtensa/xtensa.c (revision b7b7574d3bf8eeb51a1fa3977b59142ec6434a55)
1 /* Subroutines for insn-output.c for Tensilica's Xtensa architecture.
2    Copyright 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
3    Free Software Foundation, Inc.
4    Contributed by Bob Wilson (bwilson@tensilica.com) at Tensilica.
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 #include "config.h"
23 #include "system.h"
24 #include "coretypes.h"
25 #include "tm.h"
26 #include "rtl.h"
27 #include "regs.h"
28 #include "hard-reg-set.h"
29 #include "basic-block.h"
30 #include "real.h"
31 #include "insn-config.h"
32 #include "conditions.h"
33 #include "insn-flags.h"
34 #include "insn-attr.h"
35 #include "insn-codes.h"
36 #include "recog.h"
37 #include "output.h"
38 #include "tree.h"
39 #include "expr.h"
40 #include "flags.h"
41 #include "reload.h"
42 #include "tm_p.h"
43 #include "function.h"
44 #include "toplev.h"
45 #include "optabs.h"
46 #include "libfuncs.h"
47 #include "ggc.h"
48 #include "target.h"
49 #include "target-def.h"
50 #include "langhooks.h"
51 #include "gimple.h"
52 #include "df.h"
53 
54 
55 /* Enumeration for all of the relational tests, so that we can build
56    arrays indexed by the test type, and not worry about the order
57    of EQ, NE, etc.  */
58 
59 enum internal_test
60 {
61   ITEST_EQ,
62   ITEST_NE,
63   ITEST_GT,
64   ITEST_GE,
65   ITEST_LT,
66   ITEST_LE,
67   ITEST_GTU,
68   ITEST_GEU,
69   ITEST_LTU,
70   ITEST_LEU,
71   ITEST_MAX
72 };
73 
74 /* Array giving truth value on whether or not a given hard register
75    can support a given mode.  */
76 char xtensa_hard_regno_mode_ok[(int) MAX_MACHINE_MODE][FIRST_PSEUDO_REGISTER];
77 
78 /* Current frame size calculated by compute_frame_size.  */
79 unsigned xtensa_current_frame_size;
80 
81 /* Largest block move to handle in-line.  */
82 #define LARGEST_MOVE_RATIO 15
83 
84 /* Define the structure for the machine field in struct function.  */
85 struct GTY(()) machine_function
86 {
87   int accesses_prev_frame;
88   bool need_a7_copy;
89   bool vararg_a7;
90   rtx vararg_a7_copy;
91   rtx set_frame_ptr_insn;
92 };
93 
94 /* Vector, indexed by hard register number, which contains 1 for a
95    register that is allowable in a candidate for leaf function
96    treatment.  */
97 
98 const char xtensa_leaf_regs[FIRST_PSEUDO_REGISTER] =
99 {
100   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
101   1, 1, 1,
102   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
103   1
104 };
105 
106 /* Map hard register number to register class */
107 const enum reg_class xtensa_regno_to_class[FIRST_PSEUDO_REGISTER] =
108 {
109   RL_REGS,	SP_REG,		RL_REGS,	RL_REGS,
110   RL_REGS,	RL_REGS,	RL_REGS,	GR_REGS,
111   RL_REGS,	RL_REGS,	RL_REGS,	RL_REGS,
112   RL_REGS,	RL_REGS,	RL_REGS,	RL_REGS,
113   AR_REGS,	AR_REGS,	BR_REGS,
114   FP_REGS,	FP_REGS,	FP_REGS,	FP_REGS,
115   FP_REGS,	FP_REGS,	FP_REGS,	FP_REGS,
116   FP_REGS,	FP_REGS,	FP_REGS,	FP_REGS,
117   FP_REGS,	FP_REGS,	FP_REGS,	FP_REGS,
118   ACC_REG,
119 };
120 
121 static enum internal_test map_test_to_internal_test (enum rtx_code);
122 static rtx gen_int_relational (enum rtx_code, rtx, rtx, int *);
123 static rtx gen_float_relational (enum rtx_code, rtx, rtx);
124 static rtx gen_conditional_move (enum rtx_code, enum machine_mode, rtx, rtx);
125 static rtx fixup_subreg_mem (rtx);
126 static struct machine_function * xtensa_init_machine_status (void);
127 static rtx xtensa_legitimize_tls_address (rtx);
128 static rtx xtensa_legitimize_address (rtx, rtx, enum machine_mode);
129 static bool xtensa_return_in_msb (const_tree);
130 static void printx (FILE *, signed int);
131 static void xtensa_function_epilogue (FILE *, HOST_WIDE_INT);
132 static rtx xtensa_builtin_saveregs (void);
133 static bool xtensa_legitimate_address_p (enum machine_mode, rtx, bool);
134 static unsigned int xtensa_multibss_section_type_flags (tree, const char *,
135 							int) ATTRIBUTE_UNUSED;
136 static section *xtensa_select_rtx_section (enum machine_mode, rtx,
137 					   unsigned HOST_WIDE_INT);
138 static bool xtensa_rtx_costs (rtx, int, int, int *, bool);
139 static tree xtensa_build_builtin_va_list (void);
140 static bool xtensa_return_in_memory (const_tree, const_tree);
141 static tree xtensa_gimplify_va_arg_expr (tree, tree, gimple_seq *,
142 					 gimple_seq *);
143 static rtx xtensa_function_value (const_tree, const_tree, bool);
144 static void xtensa_init_builtins (void);
145 static tree xtensa_fold_builtin (tree, tree, bool);
146 static rtx xtensa_expand_builtin (tree, rtx, rtx, enum machine_mode, int);
147 static void xtensa_va_start (tree, rtx);
148 static bool xtensa_frame_pointer_required (void);
149 static rtx xtensa_static_chain (const_tree, bool);
150 static void xtensa_asm_trampoline_template (FILE *);
151 static void xtensa_trampoline_init (rtx, tree, rtx);
152 
153 static const int reg_nonleaf_alloc_order[FIRST_PSEUDO_REGISTER] =
154   REG_ALLOC_ORDER;
155 
156 
157 /* This macro generates the assembly code for function exit,
158    on machines that need it.  If FUNCTION_EPILOGUE is not defined
159    then individual return instructions are generated for each
160    return statement.  Args are same as for FUNCTION_PROLOGUE.  */
161 
162 #undef TARGET_ASM_FUNCTION_EPILOGUE
163 #define TARGET_ASM_FUNCTION_EPILOGUE xtensa_function_epilogue
164 
165 /* These hooks specify assembly directives for creating certain kinds
166    of integer object.  */
167 
168 #undef TARGET_ASM_ALIGNED_SI_OP
169 #define TARGET_ASM_ALIGNED_SI_OP "\t.word\t"
170 
171 #undef TARGET_ASM_SELECT_RTX_SECTION
172 #define TARGET_ASM_SELECT_RTX_SECTION  xtensa_select_rtx_section
173 
174 #undef TARGET_DEFAULT_TARGET_FLAGS
175 #define TARGET_DEFAULT_TARGET_FLAGS (TARGET_DEFAULT | MASK_FUSED_MADD)
176 
177 #undef TARGET_LEGITIMIZE_ADDRESS
178 #define TARGET_LEGITIMIZE_ADDRESS xtensa_legitimize_address
179 
180 #undef TARGET_RTX_COSTS
181 #define TARGET_RTX_COSTS xtensa_rtx_costs
182 #undef TARGET_ADDRESS_COST
183 #define TARGET_ADDRESS_COST hook_int_rtx_bool_0
184 
185 #undef TARGET_BUILD_BUILTIN_VA_LIST
186 #define TARGET_BUILD_BUILTIN_VA_LIST xtensa_build_builtin_va_list
187 
188 #undef TARGET_EXPAND_BUILTIN_VA_START
189 #define TARGET_EXPAND_BUILTIN_VA_START xtensa_va_start
190 
191 #undef TARGET_PROMOTE_FUNCTION_MODE
192 #define TARGET_PROMOTE_FUNCTION_MODE default_promote_function_mode_always_promote
193 #undef TARGET_PROMOTE_PROTOTYPES
194 #define TARGET_PROMOTE_PROTOTYPES hook_bool_const_tree_true
195 
196 #undef TARGET_RETURN_IN_MEMORY
197 #define TARGET_RETURN_IN_MEMORY xtensa_return_in_memory
198 #undef TARGET_FUNCTION_VALUE
199 #define TARGET_FUNCTION_VALUE xtensa_function_value
200 #undef TARGET_SPLIT_COMPLEX_ARG
201 #define TARGET_SPLIT_COMPLEX_ARG hook_bool_const_tree_true
202 #undef TARGET_MUST_PASS_IN_STACK
203 #define TARGET_MUST_PASS_IN_STACK must_pass_in_stack_var_size
204 
205 #undef TARGET_EXPAND_BUILTIN_SAVEREGS
206 #define TARGET_EXPAND_BUILTIN_SAVEREGS xtensa_builtin_saveregs
207 #undef TARGET_GIMPLIFY_VA_ARG_EXPR
208 #define TARGET_GIMPLIFY_VA_ARG_EXPR xtensa_gimplify_va_arg_expr
209 
210 #undef TARGET_RETURN_IN_MSB
211 #define TARGET_RETURN_IN_MSB xtensa_return_in_msb
212 
213 #undef  TARGET_INIT_BUILTINS
214 #define TARGET_INIT_BUILTINS xtensa_init_builtins
215 #undef  TARGET_FOLD_BUILTIN
216 #define TARGET_FOLD_BUILTIN xtensa_fold_builtin
217 #undef  TARGET_EXPAND_BUILTIN
218 #define TARGET_EXPAND_BUILTIN xtensa_expand_builtin
219 
220 #undef TARGET_SECONDARY_RELOAD
221 #define TARGET_SECONDARY_RELOAD xtensa_secondary_reload
222 
223 #undef TARGET_HAVE_TLS
224 #define TARGET_HAVE_TLS (TARGET_THREADPTR && HAVE_AS_TLS)
225 
226 #undef TARGET_CANNOT_FORCE_CONST_MEM
227 #define TARGET_CANNOT_FORCE_CONST_MEM xtensa_tls_referenced_p
228 
229 #undef TARGET_LEGITIMATE_ADDRESS_P
230 #define TARGET_LEGITIMATE_ADDRESS_P	xtensa_legitimate_address_p
231 
232 #undef TARGET_FRAME_POINTER_REQUIRED
233 #define TARGET_FRAME_POINTER_REQUIRED xtensa_frame_pointer_required
234 
235 #undef TARGET_STATIC_CHAIN
236 #define TARGET_STATIC_CHAIN xtensa_static_chain
237 #undef TARGET_ASM_TRAMPOLINE_TEMPLATE
238 #define TARGET_ASM_TRAMPOLINE_TEMPLATE xtensa_asm_trampoline_template
239 #undef TARGET_TRAMPOLINE_INIT
240 #define TARGET_TRAMPOLINE_INIT xtensa_trampoline_init
241 
242 struct gcc_target targetm = TARGET_INITIALIZER;
243 
244 
245 /* Functions to test Xtensa immediate operand validity.  */
246 
247 bool
248 xtensa_simm8 (HOST_WIDE_INT v)
249 {
250   return v >= -128 && v <= 127;
251 }
252 
253 
254 bool
255 xtensa_simm8x256 (HOST_WIDE_INT v)
256 {
257   return (v & 255) == 0 && (v >= -32768 && v <= 32512);
258 }
259 
260 
261 bool
262 xtensa_simm12b (HOST_WIDE_INT v)
263 {
264   return v >= -2048 && v <= 2047;
265 }
266 
267 
268 static bool
269 xtensa_uimm8 (HOST_WIDE_INT v)
270 {
271   return v >= 0 && v <= 255;
272 }
273 
274 
275 static bool
276 xtensa_uimm8x2 (HOST_WIDE_INT v)
277 {
278   return (v & 1) == 0 && (v >= 0 && v <= 510);
279 }
280 
281 
282 static bool
283 xtensa_uimm8x4 (HOST_WIDE_INT v)
284 {
285   return (v & 3) == 0 && (v >= 0 && v <= 1020);
286 }
287 
288 
289 static bool
290 xtensa_b4const (HOST_WIDE_INT v)
291 {
292   switch (v)
293     {
294     case -1:
295     case 1:
296     case 2:
297     case 3:
298     case 4:
299     case 5:
300     case 6:
301     case 7:
302     case 8:
303     case 10:
304     case 12:
305     case 16:
306     case 32:
307     case 64:
308     case 128:
309     case 256:
310       return true;
311     }
312   return false;
313 }
314 
315 
316 bool
317 xtensa_b4const_or_zero (HOST_WIDE_INT v)
318 {
319   if (v == 0)
320     return true;
321   return xtensa_b4const (v);
322 }
323 
324 
325 bool
326 xtensa_b4constu (HOST_WIDE_INT v)
327 {
328   switch (v)
329     {
330     case 32768:
331     case 65536:
332     case 2:
333     case 3:
334     case 4:
335     case 5:
336     case 6:
337     case 7:
338     case 8:
339     case 10:
340     case 12:
341     case 16:
342     case 32:
343     case 64:
344     case 128:
345     case 256:
346       return true;
347     }
348   return false;
349 }
350 
351 
352 bool
353 xtensa_mask_immediate (HOST_WIDE_INT v)
354 {
355 #define MAX_MASK_SIZE 16
356   int mask_size;
357 
358   for (mask_size = 1; mask_size <= MAX_MASK_SIZE; mask_size++)
359     {
360       if ((v & 1) == 0)
361 	return false;
362       v = v >> 1;
363       if (v == 0)
364 	return true;
365     }
366 
367   return false;
368 }
369 
370 
371 /* This is just like the standard true_regnum() function except that it
372    works even when reg_renumber is not initialized.  */
373 
374 int
375 xt_true_regnum (rtx x)
376 {
377   if (GET_CODE (x) == REG)
378     {
379       if (reg_renumber
380 	  && REGNO (x) >= FIRST_PSEUDO_REGISTER
381 	  && reg_renumber[REGNO (x)] >= 0)
382 	return reg_renumber[REGNO (x)];
383       return REGNO (x);
384     }
385   if (GET_CODE (x) == SUBREG)
386     {
387       int base = xt_true_regnum (SUBREG_REG (x));
388       if (base >= 0 && base < FIRST_PSEUDO_REGISTER)
389         return base + subreg_regno_offset (REGNO (SUBREG_REG (x)),
390                                            GET_MODE (SUBREG_REG (x)),
391                                            SUBREG_BYTE (x), GET_MODE (x));
392     }
393   return -1;
394 }
395 
396 
397 int
398 xtensa_valid_move (enum machine_mode mode, rtx *operands)
399 {
400   /* Either the destination or source must be a register, and the
401      MAC16 accumulator doesn't count.  */
402 
403   if (register_operand (operands[0], mode))
404     {
405       int dst_regnum = xt_true_regnum (operands[0]);
406 
407       /* The stack pointer can only be assigned with a MOVSP opcode.  */
408       if (dst_regnum == STACK_POINTER_REGNUM)
409 	return (mode == SImode
410 		&& register_operand (operands[1], mode)
411 		&& !ACC_REG_P (xt_true_regnum (operands[1])));
412 
413       if (!ACC_REG_P (dst_regnum))
414 	return true;
415     }
416   if (register_operand (operands[1], mode))
417     {
418       int src_regnum = xt_true_regnum (operands[1]);
419       if (!ACC_REG_P (src_regnum))
420 	return true;
421     }
422   return FALSE;
423 }
424 
425 
426 int
427 smalloffset_mem_p (rtx op)
428 {
429   if (GET_CODE (op) == MEM)
430     {
431       rtx addr = XEXP (op, 0);
432       if (GET_CODE (addr) == REG)
433 	return BASE_REG_P (addr, 0);
434       if (GET_CODE (addr) == PLUS)
435 	{
436 	  rtx offset = XEXP (addr, 0);
437 	  HOST_WIDE_INT val;
438 	  if (GET_CODE (offset) != CONST_INT)
439 	    offset = XEXP (addr, 1);
440 	  if (GET_CODE (offset) != CONST_INT)
441 	    return FALSE;
442 
443 	  val = INTVAL (offset);
444 	  return (val & 3) == 0 && (val >= 0 && val <= 60);
445 	}
446     }
447   return FALSE;
448 }
449 
450 
451 int
452 constantpool_address_p (rtx addr)
453 {
454   rtx sym = addr;
455 
456   if (GET_CODE (addr) == CONST)
457     {
458       rtx offset;
459 
460       /* Only handle (PLUS (SYM, OFFSET)) form.  */
461       addr = XEXP (addr, 0);
462       if (GET_CODE (addr) != PLUS)
463 	return FALSE;
464 
465       /* Make sure the address is word aligned.  */
466       offset = XEXP (addr, 1);
467       if ((GET_CODE (offset) != CONST_INT)
468 	  || ((INTVAL (offset) & 3) != 0))
469 	return FALSE;
470 
471       sym = XEXP (addr, 0);
472     }
473 
474   if ((GET_CODE (sym) == SYMBOL_REF)
475       && CONSTANT_POOL_ADDRESS_P (sym))
476     return TRUE;
477   return FALSE;
478 }
479 
480 
481 int
482 constantpool_mem_p (rtx op)
483 {
484   if (GET_CODE (op) == SUBREG)
485     op = SUBREG_REG (op);
486   if (GET_CODE (op) == MEM)
487     return constantpool_address_p (XEXP (op, 0));
488   return FALSE;
489 }
490 
491 
492 /* Return TRUE if X is a thread-local symbol.  */
493 
494 static bool
495 xtensa_tls_symbol_p (rtx x)
496 {
497   if (! TARGET_HAVE_TLS)
498     return false;
499 
500   return GET_CODE (x) == SYMBOL_REF && SYMBOL_REF_TLS_MODEL (x) != 0;
501 }
502 
503 
504 void
505 xtensa_extend_reg (rtx dst, rtx src)
506 {
507   rtx temp = gen_reg_rtx (SImode);
508   rtx shift = GEN_INT (BITS_PER_WORD - GET_MODE_BITSIZE (GET_MODE (src)));
509 
510   /* Generate paradoxical subregs as needed so that the modes match.  */
511   src = simplify_gen_subreg (SImode, src, GET_MODE (src), 0);
512   dst = simplify_gen_subreg (SImode, dst, GET_MODE (dst), 0);
513 
514   emit_insn (gen_ashlsi3 (temp, src, shift));
515   emit_insn (gen_ashrsi3 (dst, temp, shift));
516 }
517 
518 
519 bool
520 xtensa_mem_offset (unsigned v, enum machine_mode mode)
521 {
522   switch (mode)
523     {
524     case BLKmode:
525       /* Handle the worst case for block moves.  See xtensa_expand_block_move
526 	 where we emit an optimized block move operation if the block can be
527 	 moved in < "move_ratio" pieces.  The worst case is when the block is
528 	 aligned but has a size of (3 mod 4) (does this happen?) so that the
529 	 last piece requires a byte load/store.  */
530       return (xtensa_uimm8 (v)
531 	      && xtensa_uimm8 (v + MOVE_MAX * LARGEST_MOVE_RATIO));
532 
533     case QImode:
534       return xtensa_uimm8 (v);
535 
536     case HImode:
537       return xtensa_uimm8x2 (v);
538 
539     case DFmode:
540       return (xtensa_uimm8x4 (v) && xtensa_uimm8x4 (v + 4));
541 
542     default:
543       break;
544     }
545 
546   return xtensa_uimm8x4 (v);
547 }
548 
549 
550 /* Make normal rtx_code into something we can index from an array.  */
551 
552 static enum internal_test
553 map_test_to_internal_test (enum rtx_code test_code)
554 {
555   enum internal_test test = ITEST_MAX;
556 
557   switch (test_code)
558     {
559     default:			break;
560     case EQ:  test = ITEST_EQ;  break;
561     case NE:  test = ITEST_NE;  break;
562     case GT:  test = ITEST_GT;  break;
563     case GE:  test = ITEST_GE;  break;
564     case LT:  test = ITEST_LT;  break;
565     case LE:  test = ITEST_LE;  break;
566     case GTU: test = ITEST_GTU; break;
567     case GEU: test = ITEST_GEU; break;
568     case LTU: test = ITEST_LTU; break;
569     case LEU: test = ITEST_LEU; break;
570     }
571 
572   return test;
573 }
574 
575 
576 /* Generate the code to compare two integer values.  The return value is
577    the comparison expression.  */
578 
579 static rtx
580 gen_int_relational (enum rtx_code test_code, /* relational test (EQ, etc) */
581 		    rtx cmp0, /* first operand to compare */
582 		    rtx cmp1, /* second operand to compare */
583 		    int *p_invert /* whether branch needs to reverse test */)
584 {
585   struct cmp_info
586   {
587     enum rtx_code test_code;	/* test code to use in insn */
588     bool (*const_range_p) (HOST_WIDE_INT); /* range check function */
589     int const_add;		/* constant to add (convert LE -> LT) */
590     int reverse_regs;		/* reverse registers in test */
591     int invert_const;		/* != 0 if invert value if cmp1 is constant */
592     int invert_reg;		/* != 0 if invert value if cmp1 is register */
593     int unsignedp;		/* != 0 for unsigned comparisons.  */
594   };
595 
596   static struct cmp_info info[ (int)ITEST_MAX ] = {
597 
598     { EQ,	xtensa_b4const_or_zero,	0, 0, 0, 0, 0 },	/* EQ  */
599     { NE,	xtensa_b4const_or_zero,	0, 0, 0, 0, 0 },	/* NE  */
600 
601     { LT,	xtensa_b4const_or_zero,	1, 1, 1, 0, 0 },	/* GT  */
602     { GE,	xtensa_b4const_or_zero,	0, 0, 0, 0, 0 },	/* GE  */
603     { LT,	xtensa_b4const_or_zero,	0, 0, 0, 0, 0 },	/* LT  */
604     { GE,	xtensa_b4const_or_zero,	1, 1, 1, 0, 0 },	/* LE  */
605 
606     { LTU,	xtensa_b4constu,	1, 1, 1, 0, 1 },	/* GTU */
607     { GEU,	xtensa_b4constu,	0, 0, 0, 0, 1 },	/* GEU */
608     { LTU,	xtensa_b4constu,	0, 0, 0, 0, 1 },	/* LTU */
609     { GEU,	xtensa_b4constu,	1, 1, 1, 0, 1 },	/* LEU */
610   };
611 
612   enum internal_test test;
613   enum machine_mode mode;
614   struct cmp_info *p_info;
615 
616   test = map_test_to_internal_test (test_code);
617   gcc_assert (test != ITEST_MAX);
618 
619   p_info = &info[ (int)test ];
620 
621   mode = GET_MODE (cmp0);
622   if (mode == VOIDmode)
623     mode = GET_MODE (cmp1);
624 
625   /* Make sure we can handle any constants given to us.  */
626   if (GET_CODE (cmp1) == CONST_INT)
627     {
628       HOST_WIDE_INT value = INTVAL (cmp1);
629       unsigned HOST_WIDE_INT uvalue = (unsigned HOST_WIDE_INT)value;
630 
631       /* if the immediate overflows or does not fit in the immediate field,
632 	 spill it to a register */
633 
634       if ((p_info->unsignedp ?
635 	   (uvalue + p_info->const_add > uvalue) :
636 	   (value + p_info->const_add > value)) != (p_info->const_add > 0))
637 	{
638 	  cmp1 = force_reg (mode, cmp1);
639 	}
640       else if (!(p_info->const_range_p) (value + p_info->const_add))
641 	{
642 	  cmp1 = force_reg (mode, cmp1);
643 	}
644     }
645   else if ((GET_CODE (cmp1) != REG) && (GET_CODE (cmp1) != SUBREG))
646     {
647       cmp1 = force_reg (mode, cmp1);
648     }
649 
650   /* See if we need to invert the result.  */
651   *p_invert = ((GET_CODE (cmp1) == CONST_INT)
652 	       ? p_info->invert_const
653 	       : p_info->invert_reg);
654 
655   /* Comparison to constants, may involve adding 1 to change a LT into LE.
656      Comparison between two registers, may involve switching operands.  */
657   if (GET_CODE (cmp1) == CONST_INT)
658     {
659       if (p_info->const_add != 0)
660 	cmp1 = GEN_INT (INTVAL (cmp1) + p_info->const_add);
661 
662     }
663   else if (p_info->reverse_regs)
664     {
665       rtx temp = cmp0;
666       cmp0 = cmp1;
667       cmp1 = temp;
668     }
669 
670   return gen_rtx_fmt_ee (p_info->test_code, VOIDmode, cmp0, cmp1);
671 }
672 
673 
674 /* Generate the code to compare two float values.  The return value is
675    the comparison expression.  */
676 
677 static rtx
678 gen_float_relational (enum rtx_code test_code, /* relational test (EQ, etc) */
679 		      rtx cmp0, /* first operand to compare */
680 		      rtx cmp1 /* second operand to compare */)
681 {
682   rtx (*gen_fn) (rtx, rtx, rtx);
683   rtx brtmp;
684   int reverse_regs, invert;
685 
686   switch (test_code)
687     {
688     case EQ: reverse_regs = 0; invert = 0; gen_fn = gen_seq_sf; break;
689     case NE: reverse_regs = 0; invert = 1; gen_fn = gen_seq_sf; break;
690     case LE: reverse_regs = 0; invert = 0; gen_fn = gen_sle_sf; break;
691     case GT: reverse_regs = 1; invert = 0; gen_fn = gen_slt_sf; break;
692     case LT: reverse_regs = 0; invert = 0; gen_fn = gen_slt_sf; break;
693     case GE: reverse_regs = 1; invert = 0; gen_fn = gen_sle_sf; break;
694     case UNEQ: reverse_regs = 0; invert = 0; gen_fn = gen_suneq_sf; break;
695     case LTGT: reverse_regs = 0; invert = 1; gen_fn = gen_suneq_sf; break;
696     case UNLE: reverse_regs = 0; invert = 0; gen_fn = gen_sunle_sf; break;
697     case UNGT: reverse_regs = 1; invert = 0; gen_fn = gen_sunlt_sf; break;
698     case UNLT: reverse_regs = 0; invert = 0; gen_fn = gen_sunlt_sf; break;
699     case UNGE: reverse_regs = 1; invert = 0; gen_fn = gen_sunle_sf; break;
700     case UNORDERED:
701       reverse_regs = 0; invert = 0; gen_fn = gen_sunordered_sf; break;
702     case ORDERED:
703       reverse_regs = 0; invert = 1; gen_fn = gen_sunordered_sf; break;
704     default:
705       fatal_insn ("bad test", gen_rtx_fmt_ee (test_code, VOIDmode, cmp0, cmp1));
706       reverse_regs = 0; invert = 0; gen_fn = 0; /* avoid compiler warnings */
707     }
708 
709   if (reverse_regs)
710     {
711       rtx temp = cmp0;
712       cmp0 = cmp1;
713       cmp1 = temp;
714     }
715 
716   brtmp = gen_rtx_REG (CCmode, FPCC_REGNUM);
717   emit_insn (gen_fn (brtmp, cmp0, cmp1));
718 
719   return gen_rtx_fmt_ee (invert ? EQ : NE, VOIDmode, brtmp, const0_rtx);
720 }
721 
722 
723 void
724 xtensa_expand_conditional_branch (rtx *operands, enum machine_mode mode)
725 {
726   enum rtx_code test_code = GET_CODE (operands[0]);
727   rtx cmp0 = operands[1];
728   rtx cmp1 = operands[2];
729   rtx cmp;
730   int invert;
731   rtx label1, label2;
732 
733   switch (mode)
734     {
735     case DFmode:
736     default:
737       fatal_insn ("bad test", gen_rtx_fmt_ee (test_code, VOIDmode, cmp0, cmp1));
738 
739     case SImode:
740       invert = FALSE;
741       cmp = gen_int_relational (test_code, cmp0, cmp1, &invert);
742       break;
743 
744     case SFmode:
745       if (!TARGET_HARD_FLOAT)
746 	fatal_insn ("bad test", gen_rtx_fmt_ee (test_code, VOIDmode,
747 						cmp0, cmp1));
748       invert = FALSE;
749       cmp = gen_float_relational (test_code, cmp0, cmp1);
750       break;
751     }
752 
753   /* Generate the branch.  */
754 
755   label1 = gen_rtx_LABEL_REF (VOIDmode, operands[3]);
756   label2 = pc_rtx;
757 
758   if (invert)
759     {
760       label2 = label1;
761       label1 = pc_rtx;
762     }
763 
764   emit_jump_insn (gen_rtx_SET (VOIDmode, pc_rtx,
765 			       gen_rtx_IF_THEN_ELSE (VOIDmode, cmp,
766 						     label1,
767 						     label2)));
768 }
769 
770 
771 static rtx
772 gen_conditional_move (enum rtx_code code, enum machine_mode mode,
773 		      rtx op0, rtx op1)
774 {
775   if (mode == SImode)
776     {
777       rtx cmp;
778 
779       /* Jump optimization calls get_condition() which canonicalizes
780 	 comparisons like (GE x <const>) to (GT x <const-1>).
781 	 Transform those comparisons back to GE, since that is the
782 	 comparison supported in Xtensa.  We shouldn't have to
783 	 transform <LE x const> comparisons, because neither
784 	 xtensa_expand_conditional_branch() nor get_condition() will
785 	 produce them.  */
786 
787       if ((code == GT) && (op1 == constm1_rtx))
788 	{
789 	  code = GE;
790 	  op1 = const0_rtx;
791 	}
792       cmp = gen_rtx_fmt_ee (code, VOIDmode, cc0_rtx, const0_rtx);
793 
794       if (boolean_operator (cmp, VOIDmode))
795 	{
796 	  /* Swap the operands to make const0 second.  */
797 	  if (op0 == const0_rtx)
798 	    {
799 	      op0 = op1;
800 	      op1 = const0_rtx;
801 	    }
802 
803 	  /* If not comparing against zero, emit a comparison (subtract).  */
804 	  if (op1 != const0_rtx)
805 	    {
806 	      op0 = expand_binop (SImode, sub_optab, op0, op1,
807 				  0, 0, OPTAB_LIB_WIDEN);
808 	      op1 = const0_rtx;
809 	    }
810 	}
811       else if (branch_operator (cmp, VOIDmode))
812 	{
813 	  /* Swap the operands to make const0 second.  */
814 	  if (op0 == const0_rtx)
815 	    {
816 	      op0 = op1;
817 	      op1 = const0_rtx;
818 
819 	      switch (code)
820 		{
821 		case LT: code = GE; break;
822 		case GE: code = LT; break;
823 		default: gcc_unreachable ();
824 		}
825 	    }
826 
827 	  if (op1 != const0_rtx)
828 	    return 0;
829 	}
830       else
831 	return 0;
832 
833       return gen_rtx_fmt_ee (code, VOIDmode, op0, op1);
834     }
835 
836   if (TARGET_HARD_FLOAT && mode == SFmode)
837     return gen_float_relational (code, op0, op1);
838 
839   return 0;
840 }
841 
842 
843 int
844 xtensa_expand_conditional_move (rtx *operands, int isflt)
845 {
846   rtx dest = operands[0];
847   rtx cmp = operands[1];
848   enum machine_mode cmp_mode = GET_MODE (XEXP (cmp, 0));
849   rtx (*gen_fn) (rtx, rtx, rtx, rtx, rtx);
850 
851   if (!(cmp = gen_conditional_move (GET_CODE (cmp), cmp_mode,
852 				    XEXP (cmp, 0), XEXP (cmp, 1))))
853     return 0;
854 
855   if (isflt)
856     gen_fn = (cmp_mode == SImode
857 	      ? gen_movsfcc_internal0
858 	      : gen_movsfcc_internal1);
859   else
860     gen_fn = (cmp_mode == SImode
861 	      ? gen_movsicc_internal0
862 	      : gen_movsicc_internal1);
863 
864   emit_insn (gen_fn (dest, XEXP (cmp, 0), operands[2], operands[3], cmp));
865   return 1;
866 }
867 
868 
869 int
870 xtensa_expand_scc (rtx operands[4], enum machine_mode cmp_mode)
871 {
872   rtx dest = operands[0];
873   rtx cmp;
874   rtx one_tmp, zero_tmp;
875   rtx (*gen_fn) (rtx, rtx, rtx, rtx, rtx);
876 
877   if (!(cmp = gen_conditional_move (GET_CODE (operands[1]), cmp_mode,
878 				    operands[2], operands[3])))
879     return 0;
880 
881   one_tmp = gen_reg_rtx (SImode);
882   zero_tmp = gen_reg_rtx (SImode);
883   emit_insn (gen_movsi (one_tmp, const_true_rtx));
884   emit_insn (gen_movsi (zero_tmp, const0_rtx));
885 
886   gen_fn = (cmp_mode == SImode
887 	    ? gen_movsicc_internal0
888 	    : gen_movsicc_internal1);
889   emit_insn (gen_fn (dest, XEXP (cmp, 0), one_tmp, zero_tmp, cmp));
890   return 1;
891 }
892 
893 
894 /* Split OP[1] into OP[2,3] and likewise for OP[0] into OP[0,1].  MODE is
895    for the output, i.e., the input operands are twice as big as MODE.  */
896 
897 void
898 xtensa_split_operand_pair (rtx operands[4], enum machine_mode mode)
899 {
900   switch (GET_CODE (operands[1]))
901     {
902     case REG:
903       operands[3] = gen_rtx_REG (mode, REGNO (operands[1]) + 1);
904       operands[2] = gen_rtx_REG (mode, REGNO (operands[1]));
905       break;
906 
907     case MEM:
908       operands[3] = adjust_address (operands[1], mode, GET_MODE_SIZE (mode));
909       operands[2] = adjust_address (operands[1], mode, 0);
910       break;
911 
912     case CONST_INT:
913     case CONST_DOUBLE:
914       split_double (operands[1], &operands[2], &operands[3]);
915       break;
916 
917     default:
918       gcc_unreachable ();
919     }
920 
921   switch (GET_CODE (operands[0]))
922     {
923     case REG:
924       operands[1] = gen_rtx_REG (mode, REGNO (operands[0]) + 1);
925       operands[0] = gen_rtx_REG (mode, REGNO (operands[0]));
926       break;
927 
928     case MEM:
929       operands[1] = adjust_address (operands[0], mode, GET_MODE_SIZE (mode));
930       operands[0] = adjust_address (operands[0], mode, 0);
931       break;
932 
933     default:
934       gcc_unreachable ();
935     }
936 }
937 
938 
939 /* Emit insns to move operands[1] into operands[0].
940    Return 1 if we have written out everything that needs to be done to
941    do the move.  Otherwise, return 0 and the caller will emit the move
942    normally.  */
943 
944 int
945 xtensa_emit_move_sequence (rtx *operands, enum machine_mode mode)
946 {
947   rtx src = operands[1];
948 
949   if (CONSTANT_P (src)
950       && (GET_CODE (src) != CONST_INT || ! xtensa_simm12b (INTVAL (src))))
951     {
952       rtx dst = operands[0];
953 
954       if (xtensa_tls_referenced_p (src))
955 	{
956 	  rtx addend = NULL;
957 
958 	  if (GET_CODE (src) == CONST && GET_CODE (XEXP (src, 0)) == PLUS)
959 	    {
960 	      addend = XEXP (XEXP (src, 0), 1);
961 	      src = XEXP (XEXP (src, 0), 0);
962 	    }
963 
964 	  src = xtensa_legitimize_tls_address (src);
965 	  if (addend)
966 	    {
967 	      src = gen_rtx_PLUS (mode, src, addend);
968 	      src = force_operand (src, dst);
969 	    }
970 	  emit_move_insn (dst, src);
971 	  return 1;
972 	}
973 
974       if (! TARGET_CONST16)
975 	{
976 	  src = force_const_mem (SImode, src);
977 	  operands[1] = src;
978 	}
979 
980       /* PC-relative loads are always SImode, and CONST16 is only
981 	 supported in the movsi pattern, so add a SUBREG for any other
982 	 (smaller) mode.  */
983 
984       if (mode != SImode)
985 	{
986 	  if (register_operand (dst, mode))
987 	    {
988 	      emit_move_insn (simplify_gen_subreg (SImode, dst, mode, 0), src);
989 	      return 1;
990 	    }
991 	  else
992 	    {
993 	      src = force_reg (SImode, src);
994 	      src = gen_lowpart_SUBREG (mode, src);
995 	      operands[1] = src;
996 	    }
997 	}
998     }
999 
1000   if (!(reload_in_progress | reload_completed)
1001       && !xtensa_valid_move (mode, operands))
1002     operands[1] = force_reg (mode, operands[1]);
1003 
1004   operands[1] = xtensa_copy_incoming_a7 (operands[1]);
1005 
1006   /* During reload we don't want to emit (subreg:X (mem:Y)) since that
1007      instruction won't be recognized after reload, so we remove the
1008      subreg and adjust mem accordingly.  */
1009   if (reload_in_progress)
1010     {
1011       operands[0] = fixup_subreg_mem (operands[0]);
1012       operands[1] = fixup_subreg_mem (operands[1]);
1013     }
1014   return 0;
1015 }
1016 
1017 
1018 static rtx
1019 fixup_subreg_mem (rtx x)
1020 {
1021   if (GET_CODE (x) == SUBREG
1022       && GET_CODE (SUBREG_REG (x)) == REG
1023       && REGNO (SUBREG_REG (x)) >= FIRST_PSEUDO_REGISTER)
1024     {
1025       rtx temp =
1026 	gen_rtx_SUBREG (GET_MODE (x),
1027 			reg_equiv_mem [REGNO (SUBREG_REG (x))],
1028 			SUBREG_BYTE (x));
1029       x = alter_subreg (&temp);
1030     }
1031   return x;
1032 }
1033 
1034 
1035 /* Check if an incoming argument in a7 is expected to be used soon and
1036    if OPND is a register or register pair that includes a7.  If so,
1037    create a new pseudo and copy a7 into that pseudo at the very
1038    beginning of the function, followed by the special "set_frame_ptr"
1039    unspec_volatile insn.  The return value is either the original
1040    operand, if it is not a7, or the new pseudo containing a copy of
1041    the incoming argument.  This is necessary because the register
1042    allocator will ignore conflicts with a7 and may either assign some
1043    other pseudo to a7 or use a7 as the hard_frame_pointer, clobbering
1044    the incoming argument in a7.  By copying the argument out of a7 as
1045    the very first thing, and then immediately following that with an
1046    unspec_volatile to keep the scheduler away, we should avoid any
1047    problems.  Putting the set_frame_ptr insn at the beginning, with
1048    only the a7 copy before it, also makes it easier for the prologue
1049    expander to initialize the frame pointer after the a7 copy and to
1050    fix up the a7 copy to use the stack pointer instead of the frame
1051    pointer.  */
1052 
1053 rtx
1054 xtensa_copy_incoming_a7 (rtx opnd)
1055 {
1056   rtx entry_insns = 0;
1057   rtx reg, tmp;
1058   enum machine_mode mode;
1059 
1060   if (!cfun->machine->need_a7_copy)
1061     return opnd;
1062 
1063   /* This function should never be called again once a7 has been copied.  */
1064   gcc_assert (!cfun->machine->set_frame_ptr_insn);
1065 
1066   mode = GET_MODE (opnd);
1067 
1068   /* The operand using a7 may come in a later instruction, so just return
1069      the original operand if it doesn't use a7.  */
1070   reg = opnd;
1071   if (GET_CODE (reg) == SUBREG)
1072     {
1073       gcc_assert (SUBREG_BYTE (reg) == 0);
1074       reg = SUBREG_REG (reg);
1075     }
1076   if (GET_CODE (reg) != REG
1077       || REGNO (reg) > A7_REG
1078       || REGNO (reg) + HARD_REGNO_NREGS (A7_REG, mode) <= A7_REG)
1079     return opnd;
1080 
1081   /* 1-word args will always be in a7; 2-word args in a6/a7.  */
1082   gcc_assert (REGNO (reg) + HARD_REGNO_NREGS (A7_REG, mode) - 1 == A7_REG);
1083 
1084   cfun->machine->need_a7_copy = false;
1085 
1086   /* Copy a7 to a new pseudo at the function entry.  Use gen_raw_REG to
1087      create the REG for a7 so that hard_frame_pointer_rtx is not used.  */
1088 
1089   start_sequence ();
1090   tmp = gen_reg_rtx (mode);
1091 
1092   switch (mode)
1093     {
1094     case DFmode:
1095     case DImode:
1096       /* Copy the value out of A7 here but keep the first word in A6 until
1097 	 after the set_frame_ptr insn.  Otherwise, the register allocator
1098 	 may decide to put "subreg (tmp, 0)" in A7 and clobber the incoming
1099 	 value.  */
1100       emit_insn (gen_movsi_internal (gen_rtx_SUBREG (SImode, tmp, 4),
1101 				     gen_raw_REG (SImode, A7_REG)));
1102       break;
1103     case SFmode:
1104       emit_insn (gen_movsf_internal (tmp, gen_raw_REG (mode, A7_REG)));
1105       break;
1106     case SImode:
1107       emit_insn (gen_movsi_internal (tmp, gen_raw_REG (mode, A7_REG)));
1108       break;
1109     case HImode:
1110       emit_insn (gen_movhi_internal (tmp, gen_raw_REG (mode, A7_REG)));
1111       break;
1112     case QImode:
1113       emit_insn (gen_movqi_internal (tmp, gen_raw_REG (mode, A7_REG)));
1114       break;
1115     default:
1116       gcc_unreachable ();
1117     }
1118 
1119   cfun->machine->set_frame_ptr_insn = emit_insn (gen_set_frame_ptr ());
1120 
1121   /* For DF and DI mode arguments, copy the incoming value in A6 now.  */
1122   if (mode == DFmode || mode == DImode)
1123     emit_insn (gen_movsi_internal (gen_rtx_SUBREG (SImode, tmp, 0),
1124 				   gen_rtx_REG (SImode, A7_REG - 1)));
1125   entry_insns = get_insns ();
1126   end_sequence ();
1127 
1128   if (cfun->machine->vararg_a7)
1129     {
1130       /* This is called from within builtin_saveregs, which will insert the
1131 	 saveregs code at the function entry, ahead of anything placed at
1132 	 the function entry now.  Instead, save the sequence to be inserted
1133 	 at the beginning of the saveregs code.  */
1134       cfun->machine->vararg_a7_copy = entry_insns;
1135     }
1136   else
1137     {
1138       /* Put entry_insns after the NOTE that starts the function.  If
1139 	 this is inside a start_sequence, make the outer-level insn
1140 	 chain current, so the code is placed at the start of the
1141 	 function.  */
1142       push_topmost_sequence ();
1143       /* Do not use entry_of_function() here.  This is called from within
1144 	 expand_function_start, when the CFG still holds GIMPLE.  */
1145       emit_insn_after (entry_insns, get_insns ());
1146       pop_topmost_sequence ();
1147     }
1148 
1149   return tmp;
1150 }
1151 
1152 
1153 /* Try to expand a block move operation to a sequence of RTL move
1154    instructions.  If not optimizing, or if the block size is not a
1155    constant, or if the block is too large, the expansion fails and GCC
1156    falls back to calling memcpy().
1157 
1158    operands[0] is the destination
1159    operands[1] is the source
1160    operands[2] is the length
1161    operands[3] is the alignment */
1162 
1163 int
1164 xtensa_expand_block_move (rtx *operands)
1165 {
1166   static const enum machine_mode mode_from_align[] =
1167   {
1168     VOIDmode, QImode, HImode, VOIDmode, SImode,
1169   };
1170 
1171   rtx dst_mem = operands[0];
1172   rtx src_mem = operands[1];
1173   HOST_WIDE_INT bytes, align;
1174   int num_pieces, move_ratio;
1175   rtx temp[2];
1176   enum machine_mode mode[2];
1177   int amount[2];
1178   bool active[2];
1179   int phase = 0;
1180   int next;
1181   int offset_ld = 0;
1182   int offset_st = 0;
1183   rtx x;
1184 
1185   /* If this is not a fixed size move, just call memcpy.  */
1186   if (!optimize || (GET_CODE (operands[2]) != CONST_INT))
1187     return 0;
1188 
1189   bytes = INTVAL (operands[2]);
1190   align = INTVAL (operands[3]);
1191 
1192   /* Anything to move?  */
1193   if (bytes <= 0)
1194     return 0;
1195 
1196   if (align > MOVE_MAX)
1197     align = MOVE_MAX;
1198 
1199   /* Decide whether to expand inline based on the optimization level.  */
1200   move_ratio = 4;
1201   if (optimize > 2)
1202     move_ratio = LARGEST_MOVE_RATIO;
1203   num_pieces = (bytes / align) + (bytes % align); /* Close enough anyway.  */
1204   if (num_pieces > move_ratio)
1205     return 0;
1206 
1207   x = XEXP (dst_mem, 0);
1208   if (!REG_P (x))
1209     {
1210       x = force_reg (Pmode, x);
1211       dst_mem = replace_equiv_address (dst_mem, x);
1212     }
1213 
1214   x = XEXP (src_mem, 0);
1215   if (!REG_P (x))
1216     {
1217       x = force_reg (Pmode, x);
1218       src_mem = replace_equiv_address (src_mem, x);
1219     }
1220 
1221   active[0] = active[1] = false;
1222 
1223   do
1224     {
1225       next = phase;
1226       phase ^= 1;
1227 
1228       if (bytes > 0)
1229 	{
1230 	  int next_amount;
1231 
1232 	  next_amount = (bytes >= 4 ? 4 : (bytes >= 2 ? 2 : 1));
1233 	  next_amount = MIN (next_amount, align);
1234 
1235 	  amount[next] = next_amount;
1236 	  mode[next] = mode_from_align[next_amount];
1237 	  temp[next] = gen_reg_rtx (mode[next]);
1238 
1239 	  x = adjust_address (src_mem, mode[next], offset_ld);
1240 	  emit_insn (gen_rtx_SET (VOIDmode, temp[next], x));
1241 
1242 	  offset_ld += next_amount;
1243 	  bytes -= next_amount;
1244 	  active[next] = true;
1245 	}
1246 
1247       if (active[phase])
1248 	{
1249 	  active[phase] = false;
1250 
1251 	  x = adjust_address (dst_mem, mode[phase], offset_st);
1252 	  emit_insn (gen_rtx_SET (VOIDmode, x, temp[phase]));
1253 
1254 	  offset_st += amount[phase];
1255 	}
1256     }
1257   while (active[next]);
1258 
1259   return 1;
1260 }
1261 
1262 
1263 void
1264 xtensa_expand_nonlocal_goto (rtx *operands)
1265 {
1266   rtx goto_handler = operands[1];
1267   rtx containing_fp = operands[3];
1268 
1269   /* Generate a call to "__xtensa_nonlocal_goto" (in libgcc); the code
1270      is too big to generate in-line.  */
1271 
1272   if (GET_CODE (containing_fp) != REG)
1273     containing_fp = force_reg (Pmode, containing_fp);
1274 
1275   emit_library_call (gen_rtx_SYMBOL_REF (Pmode, "__xtensa_nonlocal_goto"),
1276 		     0, VOIDmode, 2,
1277 		     containing_fp, Pmode,
1278 		     goto_handler, Pmode);
1279 }
1280 
1281 
1282 static struct machine_function *
1283 xtensa_init_machine_status (void)
1284 {
1285   return GGC_CNEW (struct machine_function);
1286 }
1287 
1288 
1289 /* Shift VAL of mode MODE left by COUNT bits.  */
1290 
1291 static inline rtx
1292 xtensa_expand_mask_and_shift (rtx val, enum machine_mode mode, rtx count)
1293 {
1294   val = expand_simple_binop (SImode, AND, val, GEN_INT (GET_MODE_MASK (mode)),
1295 			     NULL_RTX, 1, OPTAB_DIRECT);
1296   return expand_simple_binop (SImode, ASHIFT, val, count,
1297 			      NULL_RTX, 1, OPTAB_DIRECT);
1298 }
1299 
1300 
1301 /* Structure to hold the initial parameters for a compare_and_swap operation
1302    in HImode and QImode.  */
1303 
1304 struct alignment_context
1305 {
1306   rtx memsi;	  /* SI aligned memory location.  */
1307   rtx shift;	  /* Bit offset with regard to lsb.  */
1308   rtx modemask;	  /* Mask of the HQImode shifted by SHIFT bits.  */
1309   rtx modemaski;  /* ~modemask */
1310 };
1311 
1312 
1313 /* Initialize structure AC for word access to HI and QI mode memory.  */
1314 
1315 static void
1316 init_alignment_context (struct alignment_context *ac, rtx mem)
1317 {
1318   enum machine_mode mode = GET_MODE (mem);
1319   rtx byteoffset = NULL_RTX;
1320   bool aligned = (MEM_ALIGN (mem) >= GET_MODE_BITSIZE (SImode));
1321 
1322   if (aligned)
1323     ac->memsi = adjust_address (mem, SImode, 0); /* Memory is aligned.  */
1324   else
1325     {
1326       /* Alignment is unknown.  */
1327       rtx addr, align;
1328 
1329       /* Force the address into a register.  */
1330       addr = force_reg (Pmode, XEXP (mem, 0));
1331 
1332       /* Align it to SImode.  */
1333       align = expand_simple_binop (Pmode, AND, addr,
1334 				   GEN_INT (-GET_MODE_SIZE (SImode)),
1335 				   NULL_RTX, 1, OPTAB_DIRECT);
1336       /* Generate MEM.  */
1337       ac->memsi = gen_rtx_MEM (SImode, align);
1338       MEM_VOLATILE_P (ac->memsi) = MEM_VOLATILE_P (mem);
1339       set_mem_alias_set (ac->memsi, ALIAS_SET_MEMORY_BARRIER);
1340       set_mem_align (ac->memsi, GET_MODE_BITSIZE (SImode));
1341 
1342       byteoffset = expand_simple_binop (Pmode, AND, addr,
1343 					GEN_INT (GET_MODE_SIZE (SImode) - 1),
1344 					NULL_RTX, 1, OPTAB_DIRECT);
1345     }
1346 
1347   /* Calculate shiftcount.  */
1348   if (TARGET_BIG_ENDIAN)
1349     {
1350       ac->shift = GEN_INT (GET_MODE_SIZE (SImode) - GET_MODE_SIZE (mode));
1351       if (!aligned)
1352 	ac->shift = expand_simple_binop (SImode, MINUS, ac->shift, byteoffset,
1353 					 NULL_RTX, 1, OPTAB_DIRECT);
1354     }
1355   else
1356     {
1357       if (aligned)
1358 	ac->shift = NULL_RTX;
1359       else
1360 	ac->shift = byteoffset;
1361     }
1362 
1363   if (ac->shift != NULL_RTX)
1364     {
1365       /* Shift is the byte count, but we need the bitcount.  */
1366       ac->shift = expand_simple_binop (SImode, MULT, ac->shift,
1367 				       GEN_INT (BITS_PER_UNIT),
1368 				       NULL_RTX, 1, OPTAB_DIRECT);
1369       ac->modemask = expand_simple_binop (SImode, ASHIFT,
1370 					  GEN_INT (GET_MODE_MASK (mode)),
1371 					  ac->shift,
1372 					  NULL_RTX, 1, OPTAB_DIRECT);
1373     }
1374   else
1375     ac->modemask = GEN_INT (GET_MODE_MASK (mode));
1376 
1377   ac->modemaski = expand_simple_unop (SImode, NOT, ac->modemask, NULL_RTX, 1);
1378 }
1379 
1380 
1381 /* Expand an atomic compare and swap operation for HImode and QImode.
1382    MEM is the memory location, CMP the old value to compare MEM with
1383    and NEW_RTX the value to set if CMP == MEM.  */
1384 
1385 void
1386 xtensa_expand_compare_and_swap (rtx target, rtx mem, rtx cmp, rtx new_rtx)
1387 {
1388   enum machine_mode mode = GET_MODE (mem);
1389   struct alignment_context ac;
1390   rtx tmp, cmpv, newv, val;
1391   rtx oldval = gen_reg_rtx (SImode);
1392   rtx res = gen_reg_rtx (SImode);
1393   rtx csloop = gen_label_rtx ();
1394   rtx csend = gen_label_rtx ();
1395 
1396   init_alignment_context (&ac, mem);
1397 
1398   if (ac.shift != NULL_RTX)
1399     {
1400       cmp = xtensa_expand_mask_and_shift (cmp, mode, ac.shift);
1401       new_rtx = xtensa_expand_mask_and_shift (new_rtx, mode, ac.shift);
1402     }
1403 
1404   /* Load the surrounding word into VAL with the MEM value masked out.  */
1405   val = force_reg (SImode, expand_simple_binop (SImode, AND, ac.memsi,
1406 						ac.modemaski, NULL_RTX, 1,
1407 						OPTAB_DIRECT));
1408   emit_label (csloop);
1409 
1410   /* Patch CMP and NEW_RTX into VAL at correct position.  */
1411   cmpv = force_reg (SImode, expand_simple_binop (SImode, IOR, cmp, val,
1412 						 NULL_RTX, 1, OPTAB_DIRECT));
1413   newv = force_reg (SImode, expand_simple_binop (SImode, IOR, new_rtx, val,
1414 						 NULL_RTX, 1, OPTAB_DIRECT));
1415 
1416   /* Jump to end if we're done.  */
1417   emit_insn (gen_sync_compare_and_swapsi (res, ac.memsi, cmpv, newv));
1418   emit_cmp_and_jump_insns (res, cmpv, EQ, const0_rtx, SImode, true, csend);
1419 
1420   /* Check for changes outside mode.  */
1421   emit_move_insn (oldval, val);
1422   tmp = expand_simple_binop (SImode, AND, res, ac.modemaski,
1423 			     val, 1, OPTAB_DIRECT);
1424   if (tmp != val)
1425     emit_move_insn (val, tmp);
1426 
1427   /* Loop internal if so.  */
1428   emit_cmp_and_jump_insns (oldval, val, NE, const0_rtx, SImode, true, csloop);
1429 
1430   emit_label (csend);
1431 
1432   /* Return the correct part of the bitfield.  */
1433   convert_move (target,
1434 		(ac.shift == NULL_RTX ? res
1435 		 : expand_simple_binop (SImode, LSHIFTRT, res, ac.shift,
1436 					NULL_RTX, 1, OPTAB_DIRECT)),
1437 		1);
1438 }
1439 
1440 
1441 /* Expand an atomic operation CODE of mode MODE (either HImode or QImode --
1442    the default expansion works fine for SImode).  MEM is the memory location
1443    and VAL the value to play with.  If AFTER is true then store the value
1444    MEM holds after the operation, if AFTER is false then store the value MEM
1445    holds before the operation.  If TARGET is zero then discard that value, else
1446    store it to TARGET.  */
1447 
1448 void
1449 xtensa_expand_atomic (enum rtx_code code, rtx target, rtx mem, rtx val,
1450 		      bool after)
1451 {
1452   enum machine_mode mode = GET_MODE (mem);
1453   struct alignment_context ac;
1454   rtx csloop = gen_label_rtx ();
1455   rtx cmp, tmp;
1456   rtx old = gen_reg_rtx (SImode);
1457   rtx new_rtx = gen_reg_rtx (SImode);
1458   rtx orig = NULL_RTX;
1459 
1460   init_alignment_context (&ac, mem);
1461 
1462   /* Prepare values before the compare-and-swap loop.  */
1463   if (ac.shift != NULL_RTX)
1464     val = xtensa_expand_mask_and_shift (val, mode, ac.shift);
1465   switch (code)
1466     {
1467     case PLUS:
1468     case MINUS:
1469       orig = gen_reg_rtx (SImode);
1470       convert_move (orig, val, 1);
1471       break;
1472 
1473     case SET:
1474     case IOR:
1475     case XOR:
1476       break;
1477 
1478     case MULT: /* NAND */
1479     case AND:
1480       /* val = "11..1<val>11..1" */
1481       val = expand_simple_binop (SImode, XOR, val, ac.modemaski,
1482 				 NULL_RTX, 1, OPTAB_DIRECT);
1483       break;
1484 
1485     default:
1486       gcc_unreachable ();
1487     }
1488 
1489   /* Load full word.  Subsequent loads are performed by S32C1I.  */
1490   cmp = force_reg (SImode, ac.memsi);
1491 
1492   emit_label (csloop);
1493   emit_move_insn (old, cmp);
1494 
1495   switch (code)
1496     {
1497     case PLUS:
1498     case MINUS:
1499       val = expand_simple_binop (SImode, code, old, orig,
1500 				 NULL_RTX, 1, OPTAB_DIRECT);
1501       val = expand_simple_binop (SImode, AND, val, ac.modemask,
1502 				 NULL_RTX, 1, OPTAB_DIRECT);
1503       /* FALLTHRU */
1504     case SET:
1505       tmp = expand_simple_binop (SImode, AND, old, ac.modemaski,
1506 				 NULL_RTX, 1, OPTAB_DIRECT);
1507       tmp = expand_simple_binop (SImode, IOR, tmp, val,
1508 				 new_rtx, 1, OPTAB_DIRECT);
1509       break;
1510 
1511     case AND:
1512     case IOR:
1513     case XOR:
1514       tmp = expand_simple_binop (SImode, code, old, val,
1515 				 new_rtx, 1, OPTAB_DIRECT);
1516       break;
1517 
1518     case MULT: /* NAND */
1519       tmp = expand_simple_binop (SImode, XOR, old, ac.modemask,
1520 				 NULL_RTX, 1, OPTAB_DIRECT);
1521       tmp = expand_simple_binop (SImode, AND, tmp, val,
1522 				 new_rtx, 1, OPTAB_DIRECT);
1523       break;
1524 
1525     default:
1526       gcc_unreachable ();
1527     }
1528 
1529   if (tmp != new_rtx)
1530     emit_move_insn (new_rtx, tmp);
1531   emit_insn (gen_sync_compare_and_swapsi (cmp, ac.memsi, old, new_rtx));
1532   emit_cmp_and_jump_insns (cmp, old, NE, const0_rtx, SImode, true, csloop);
1533 
1534   if (target)
1535     {
1536       tmp = (after ? new_rtx : cmp);
1537       convert_move (target,
1538 		    (ac.shift == NULL_RTX ? tmp
1539 		     : expand_simple_binop (SImode, LSHIFTRT, tmp, ac.shift,
1540 					    NULL_RTX, 1, OPTAB_DIRECT)),
1541 		    1);
1542     }
1543 }
1544 
1545 
1546 void
1547 xtensa_setup_frame_addresses (void)
1548 {
1549   /* Set flag to cause TARGET_FRAME_POINTER_REQUIRED to return true.  */
1550   cfun->machine->accesses_prev_frame = 1;
1551 
1552   emit_library_call
1553     (gen_rtx_SYMBOL_REF (Pmode, "__xtensa_libgcc_window_spill"),
1554      0, VOIDmode, 0);
1555 }
1556 
1557 
1558 /* Emit the assembly for the end of a zero-cost loop.  Normally we just emit
1559    a comment showing where the end of the loop is.  However, if there is a
1560    label or a branch at the end of the loop then we need to place a nop
1561    there.  If the loop ends with a label we need the nop so that branches
1562    targeting that label will target the nop (and thus remain in the loop),
1563    instead of targeting the instruction after the loop (and thus exiting
1564    the loop).  If the loop ends with a branch, we need the nop in case the
1565    branch is targeting a location inside the loop.  When the branch
1566    executes it will cause the loop count to be decremented even if it is
1567    taken (because it is the last instruction in the loop), so we need to
1568    nop after the branch to prevent the loop count from being decremented
1569    when the branch is taken.  */
1570 
1571 void
1572 xtensa_emit_loop_end (rtx insn, rtx *operands)
1573 {
1574   char done = 0;
1575 
1576   for (insn = PREV_INSN (insn); insn && !done; insn = PREV_INSN (insn))
1577     {
1578       switch (GET_CODE (insn))
1579 	{
1580 	case NOTE:
1581 	case BARRIER:
1582 	  break;
1583 
1584 	case CODE_LABEL:
1585 	  output_asm_insn (TARGET_DENSITY ? "nop.n" : "nop", operands);
1586 	  done = 1;
1587 	  break;
1588 
1589 	default:
1590 	  {
1591 	    rtx body = PATTERN (insn);
1592 
1593 	    if (GET_CODE (body) == JUMP_INSN)
1594 	      {
1595 		output_asm_insn (TARGET_DENSITY ? "nop.n" : "nop", operands);
1596 		done = 1;
1597 	      }
1598 	    else if ((GET_CODE (body) != USE)
1599 		     && (GET_CODE (body) != CLOBBER))
1600 	      done = 1;
1601 	  }
1602 	  break;
1603         }
1604     }
1605 
1606   output_asm_insn ("# loop end for %0", operands);
1607 }
1608 
1609 
1610 char *
1611 xtensa_emit_branch (bool inverted, bool immed, rtx *operands)
1612 {
1613   static char result[64];
1614   enum rtx_code code;
1615   const char *op;
1616 
1617   code = GET_CODE (operands[3]);
1618   switch (code)
1619     {
1620     case EQ:	op = inverted ? "ne" : "eq"; break;
1621     case NE:	op = inverted ? "eq" : "ne"; break;
1622     case LT:	op = inverted ? "ge" : "lt"; break;
1623     case GE:	op = inverted ? "lt" : "ge"; break;
1624     case LTU:	op = inverted ? "geu" : "ltu"; break;
1625     case GEU:	op = inverted ? "ltu" : "geu"; break;
1626     default:	gcc_unreachable ();
1627     }
1628 
1629   if (immed)
1630     {
1631       if (INTVAL (operands[1]) == 0)
1632 	sprintf (result, "b%sz%s\t%%0, %%2", op,
1633 		 (TARGET_DENSITY && (code == EQ || code == NE)) ? ".n" : "");
1634       else
1635 	sprintf (result, "b%si\t%%0, %%d1, %%2", op);
1636     }
1637   else
1638     sprintf (result, "b%s\t%%0, %%1, %%2", op);
1639 
1640   return result;
1641 }
1642 
1643 
1644 char *
1645 xtensa_emit_bit_branch (bool inverted, bool immed, rtx *operands)
1646 {
1647   static char result[64];
1648   const char *op;
1649 
1650   switch (GET_CODE (operands[3]))
1651     {
1652     case EQ:	op = inverted ? "bs" : "bc"; break;
1653     case NE:	op = inverted ? "bc" : "bs"; break;
1654     default:	gcc_unreachable ();
1655     }
1656 
1657   if (immed)
1658     {
1659       unsigned bitnum = INTVAL (operands[1]) & 0x1f;
1660       operands[1] = GEN_INT (bitnum);
1661       sprintf (result, "b%si\t%%0, %%d1, %%2", op);
1662     }
1663   else
1664     sprintf (result, "b%s\t%%0, %%1, %%2", op);
1665 
1666   return result;
1667 }
1668 
1669 
1670 char *
1671 xtensa_emit_movcc (bool inverted, bool isfp, bool isbool, rtx *operands)
1672 {
1673   static char result[64];
1674   enum rtx_code code;
1675   const char *op;
1676 
1677   code = GET_CODE (operands[4]);
1678   if (isbool)
1679     {
1680       switch (code)
1681 	{
1682 	case EQ:	op = inverted ? "t" : "f"; break;
1683 	case NE:	op = inverted ? "f" : "t"; break;
1684 	default:	gcc_unreachable ();
1685 	}
1686     }
1687   else
1688     {
1689       switch (code)
1690 	{
1691 	case EQ:	op = inverted ? "nez" : "eqz"; break;
1692 	case NE:	op = inverted ? "eqz" : "nez"; break;
1693 	case LT:	op = inverted ? "gez" : "ltz"; break;
1694 	case GE:	op = inverted ? "ltz" : "gez"; break;
1695 	default:	gcc_unreachable ();
1696 	}
1697     }
1698 
1699   sprintf (result, "mov%s%s\t%%0, %%%d, %%1",
1700 	   op, isfp ? ".s" : "", inverted ? 3 : 2);
1701   return result;
1702 }
1703 
1704 
1705 char *
1706 xtensa_emit_call (int callop, rtx *operands)
1707 {
1708   static char result[64];
1709   rtx tgt = operands[callop];
1710 
1711   if (GET_CODE (tgt) == CONST_INT)
1712     sprintf (result, "call8\t0x%lx", INTVAL (tgt));
1713   else if (register_operand (tgt, VOIDmode))
1714     sprintf (result, "callx8\t%%%d", callop);
1715   else
1716     sprintf (result, "call8\t%%%d", callop);
1717 
1718   return result;
1719 }
1720 
1721 
1722 bool
1723 xtensa_legitimate_address_p (enum machine_mode mode, rtx addr, bool strict)
1724 {
1725   /* Allow constant pool addresses.  */
1726   if (mode != BLKmode && GET_MODE_SIZE (mode) >= UNITS_PER_WORD
1727       && ! TARGET_CONST16 && constantpool_address_p (addr)
1728       && ! xtensa_tls_referenced_p (addr))
1729     return true;
1730 
1731   while (GET_CODE (addr) == SUBREG)
1732     addr = SUBREG_REG (addr);
1733 
1734   /* Allow base registers.  */
1735   if (GET_CODE (addr) == REG && BASE_REG_P (addr, strict))
1736     return true;
1737 
1738   /* Check for "register + offset" addressing.  */
1739   if (GET_CODE (addr) == PLUS)
1740     {
1741       rtx xplus0 = XEXP (addr, 0);
1742       rtx xplus1 = XEXP (addr, 1);
1743       enum rtx_code code0;
1744       enum rtx_code code1;
1745 
1746       while (GET_CODE (xplus0) == SUBREG)
1747 	xplus0 = SUBREG_REG (xplus0);
1748       code0 = GET_CODE (xplus0);
1749 
1750       while (GET_CODE (xplus1) == SUBREG)
1751 	xplus1 = SUBREG_REG (xplus1);
1752       code1 = GET_CODE (xplus1);
1753 
1754       /* Swap operands if necessary so the register is first.  */
1755       if (code0 != REG && code1 == REG)
1756 	{
1757 	  xplus0 = XEXP (addr, 1);
1758 	  xplus1 = XEXP (addr, 0);
1759 	  code0 = GET_CODE (xplus0);
1760 	  code1 = GET_CODE (xplus1);
1761 	}
1762 
1763       if (code0 == REG && BASE_REG_P (xplus0, strict)
1764 	  && code1 == CONST_INT
1765 	  && xtensa_mem_offset (INTVAL (xplus1), mode))
1766 	return true;
1767     }
1768 
1769   return false;
1770 }
1771 
1772 
1773 /* Construct the SYMBOL_REF for the _TLS_MODULE_BASE_ symbol.  */
1774 
1775 static GTY(()) rtx xtensa_tls_module_base_symbol;
1776 
1777 static rtx
1778 xtensa_tls_module_base (void)
1779 {
1780   if (! xtensa_tls_module_base_symbol)
1781     {
1782       xtensa_tls_module_base_symbol =
1783 	gen_rtx_SYMBOL_REF (Pmode, "_TLS_MODULE_BASE_");
1784       SYMBOL_REF_FLAGS (xtensa_tls_module_base_symbol)
1785         |= TLS_MODEL_GLOBAL_DYNAMIC << SYMBOL_FLAG_TLS_SHIFT;
1786     }
1787 
1788   return xtensa_tls_module_base_symbol;
1789 }
1790 
1791 
1792 static rtx
1793 xtensa_call_tls_desc (rtx sym, rtx *retp)
1794 {
1795   rtx fn, arg, a10, call_insn, insns;
1796 
1797   start_sequence ();
1798   fn = gen_reg_rtx (Pmode);
1799   arg = gen_reg_rtx (Pmode);
1800   a10 = gen_rtx_REG (Pmode, 10);
1801 
1802   emit_insn (gen_tls_func (fn, sym));
1803   emit_insn (gen_tls_arg (arg, sym));
1804   emit_move_insn (a10, arg);
1805   call_insn = emit_call_insn (gen_tls_call (a10, fn, sym, const1_rtx));
1806   CALL_INSN_FUNCTION_USAGE (call_insn)
1807     = gen_rtx_EXPR_LIST (VOIDmode, gen_rtx_USE (VOIDmode, a10),
1808 			 CALL_INSN_FUNCTION_USAGE (call_insn));
1809   insns = get_insns ();
1810   end_sequence ();
1811 
1812   *retp = a10;
1813   return insns;
1814 }
1815 
1816 
1817 static rtx
1818 xtensa_legitimize_tls_address (rtx x)
1819 {
1820   unsigned int model = SYMBOL_REF_TLS_MODEL (x);
1821   rtx dest, tp, ret, modbase, base, addend, insns;
1822 
1823   dest = gen_reg_rtx (Pmode);
1824   switch (model)
1825     {
1826     case TLS_MODEL_GLOBAL_DYNAMIC:
1827       insns = xtensa_call_tls_desc (x, &ret);
1828       emit_libcall_block (insns, dest, ret, x);
1829       break;
1830 
1831     case TLS_MODEL_LOCAL_DYNAMIC:
1832       base = gen_reg_rtx (Pmode);
1833       modbase = xtensa_tls_module_base ();
1834       insns = xtensa_call_tls_desc (modbase, &ret);
1835       emit_libcall_block (insns, base, ret, modbase);
1836       addend = force_reg (SImode, gen_sym_DTPOFF (x));
1837       emit_insn (gen_addsi3 (dest, base, addend));
1838       break;
1839 
1840     case TLS_MODEL_INITIAL_EXEC:
1841     case TLS_MODEL_LOCAL_EXEC:
1842       tp = gen_reg_rtx (SImode);
1843       emit_insn (gen_load_tp (tp));
1844       addend = force_reg (SImode, gen_sym_TPOFF (x));
1845       emit_insn (gen_addsi3 (dest, tp, addend));
1846       break;
1847 
1848     default:
1849       gcc_unreachable ();
1850     }
1851 
1852   return dest;
1853 }
1854 
1855 
1856 rtx
1857 xtensa_legitimize_address (rtx x,
1858 			   rtx oldx ATTRIBUTE_UNUSED,
1859 			   enum machine_mode mode)
1860 {
1861   if (xtensa_tls_symbol_p (x))
1862     return xtensa_legitimize_tls_address (x);
1863 
1864   if (GET_CODE (x) == PLUS)
1865     {
1866       rtx plus0 = XEXP (x, 0);
1867       rtx plus1 = XEXP (x, 1);
1868 
1869       if (GET_CODE (plus0) != REG && GET_CODE (plus1) == REG)
1870 	{
1871 	  plus0 = XEXP (x, 1);
1872 	  plus1 = XEXP (x, 0);
1873 	}
1874 
1875       /* Try to split up the offset to use an ADDMI instruction.  */
1876       if (GET_CODE (plus0) == REG
1877 	  && GET_CODE (plus1) == CONST_INT
1878 	  && !xtensa_mem_offset (INTVAL (plus1), mode)
1879 	  && !xtensa_simm8 (INTVAL (plus1))
1880 	  && xtensa_mem_offset (INTVAL (plus1) & 0xff, mode)
1881 	  && xtensa_simm8x256 (INTVAL (plus1) & ~0xff))
1882 	{
1883 	  rtx temp = gen_reg_rtx (Pmode);
1884 	  rtx addmi_offset = GEN_INT (INTVAL (plus1) & ~0xff);
1885 	  emit_insn (gen_rtx_SET (Pmode, temp,
1886 				  gen_rtx_PLUS (Pmode, plus0, addmi_offset)));
1887 	  return gen_rtx_PLUS (Pmode, temp, GEN_INT (INTVAL (plus1) & 0xff));
1888 	}
1889     }
1890 
1891   return x;
1892 }
1893 
1894 
1895 /* Helper for xtensa_tls_referenced_p.  */
1896 
1897 static int
1898 xtensa_tls_referenced_p_1 (rtx *x, void *data ATTRIBUTE_UNUSED)
1899 {
1900   if (GET_CODE (*x) == SYMBOL_REF)
1901     return SYMBOL_REF_TLS_MODEL (*x) != 0;
1902 
1903   /* Ignore TLS references that have already been legitimized.  */
1904   if (GET_CODE (*x) == UNSPEC)
1905     {
1906       switch (XINT (*x, 1))
1907 	{
1908 	case UNSPEC_TPOFF:
1909 	case UNSPEC_DTPOFF:
1910 	case UNSPEC_TLS_FUNC:
1911 	case UNSPEC_TLS_ARG:
1912 	case UNSPEC_TLS_CALL:
1913 	  return -1;
1914 	default:
1915 	  break;
1916 	}
1917     }
1918 
1919   return 0;
1920 }
1921 
1922 
1923 /* Return TRUE if X contains any TLS symbol references.  */
1924 
1925 bool
1926 xtensa_tls_referenced_p (rtx x)
1927 {
1928   if (! TARGET_HAVE_TLS)
1929     return false;
1930 
1931   return for_each_rtx (&x, xtensa_tls_referenced_p_1, NULL);
1932 }
1933 
1934 
1935 /* Return the debugger register number to use for 'regno'.  */
1936 
1937 int
1938 xtensa_dbx_register_number (int regno)
1939 {
1940   int first = -1;
1941 
1942   if (GP_REG_P (regno))
1943     {
1944       regno -= GP_REG_FIRST;
1945       first = 0;
1946     }
1947   else if (BR_REG_P (regno))
1948     {
1949       regno -= BR_REG_FIRST;
1950       first = 16;
1951     }
1952   else if (FP_REG_P (regno))
1953     {
1954       regno -= FP_REG_FIRST;
1955       first = 48;
1956     }
1957   else if (ACC_REG_P (regno))
1958     {
1959       first = 0x200;	/* Start of Xtensa special registers.  */
1960       regno = 16;	/* ACCLO is special register 16.  */
1961     }
1962 
1963   /* When optimizing, we sometimes get asked about pseudo-registers
1964      that don't represent hard registers.  Return 0 for these.  */
1965   if (first == -1)
1966     return 0;
1967 
1968   return first + regno;
1969 }
1970 
1971 
1972 /* Argument support functions.  */
1973 
1974 /* Initialize CUMULATIVE_ARGS for a function.  */
1975 
1976 void
1977 init_cumulative_args (CUMULATIVE_ARGS *cum, int incoming)
1978 {
1979   cum->arg_words = 0;
1980   cum->incoming = incoming;
1981 }
1982 
1983 
1984 /* Advance the argument to the next argument position.  */
1985 
1986 void
1987 function_arg_advance (CUMULATIVE_ARGS *cum, enum machine_mode mode, tree type)
1988 {
1989   int words, max;
1990   int *arg_words;
1991 
1992   arg_words = &cum->arg_words;
1993   max = MAX_ARGS_IN_REGISTERS;
1994 
1995   words = (((mode != BLKmode)
1996 	    ? (int) GET_MODE_SIZE (mode)
1997 	    : int_size_in_bytes (type)) + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
1998 
1999   if (*arg_words < max
2000       && (targetm.calls.must_pass_in_stack (mode, type)
2001 	  || *arg_words + words > max))
2002     *arg_words = max;
2003 
2004   *arg_words += words;
2005 }
2006 
2007 
2008 /* Return an RTL expression containing the register for the given mode,
2009    or 0 if the argument is to be passed on the stack.  INCOMING_P is nonzero
2010    if this is an incoming argument to the current function.  */
2011 
2012 rtx
2013 function_arg (CUMULATIVE_ARGS *cum, enum machine_mode mode, tree type,
2014 	      int incoming_p)
2015 {
2016   int regbase, words, max;
2017   int *arg_words;
2018   int regno;
2019 
2020   arg_words = &cum->arg_words;
2021   regbase = (incoming_p ? GP_ARG_FIRST : GP_OUTGOING_ARG_FIRST);
2022   max = MAX_ARGS_IN_REGISTERS;
2023 
2024   words = (((mode != BLKmode)
2025 	    ? (int) GET_MODE_SIZE (mode)
2026 	    : int_size_in_bytes (type)) + UNITS_PER_WORD - 1) / UNITS_PER_WORD;
2027 
2028   if (type && (TYPE_ALIGN (type) > BITS_PER_WORD))
2029     {
2030       int align = MIN (TYPE_ALIGN (type), STACK_BOUNDARY) / BITS_PER_WORD;
2031       *arg_words = (*arg_words + align - 1) & -align;
2032     }
2033 
2034   if (*arg_words + words > max)
2035     return (rtx)0;
2036 
2037   regno = regbase + *arg_words;
2038 
2039   if (cum->incoming && regno <= A7_REG && regno + words > A7_REG)
2040     cfun->machine->need_a7_copy = true;
2041 
2042   return gen_rtx_REG (mode, regno);
2043 }
2044 
2045 
2046 int
2047 function_arg_boundary (enum machine_mode mode, tree type)
2048 {
2049   unsigned int alignment;
2050 
2051   alignment = type ? TYPE_ALIGN (type) : GET_MODE_ALIGNMENT (mode);
2052   if (alignment < PARM_BOUNDARY)
2053     alignment = PARM_BOUNDARY;
2054   if (alignment > STACK_BOUNDARY)
2055     alignment = STACK_BOUNDARY;
2056   return alignment;
2057 }
2058 
2059 
2060 static bool
2061 xtensa_return_in_msb (const_tree valtype)
2062 {
2063   return (TARGET_BIG_ENDIAN
2064 	  && AGGREGATE_TYPE_P (valtype)
2065 	  && int_size_in_bytes (valtype) >= UNITS_PER_WORD);
2066 }
2067 
2068 
2069 void
2070 override_options (void)
2071 {
2072   int regno;
2073   enum machine_mode mode;
2074 
2075   if (!TARGET_BOOLEANS && TARGET_HARD_FLOAT)
2076     error ("boolean registers required for the floating-point option");
2077 
2078   /* Set up array giving whether a given register can hold a given mode.  */
2079   for (mode = VOIDmode;
2080        mode != MAX_MACHINE_MODE;
2081        mode = (enum machine_mode) ((int) mode + 1))
2082     {
2083       int size = GET_MODE_SIZE (mode);
2084       enum mode_class mclass = GET_MODE_CLASS (mode);
2085 
2086       for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
2087 	{
2088 	  int temp;
2089 
2090 	  if (ACC_REG_P (regno))
2091 	    temp = (TARGET_MAC16
2092 		    && (mclass == MODE_INT) && (size <= UNITS_PER_WORD));
2093 	  else if (GP_REG_P (regno))
2094 	    temp = ((regno & 1) == 0 || (size <= UNITS_PER_WORD));
2095 	  else if (FP_REG_P (regno))
2096 	    temp = (TARGET_HARD_FLOAT && (mode == SFmode));
2097 	  else if (BR_REG_P (regno))
2098 	    temp = (TARGET_BOOLEANS && (mode == CCmode));
2099 	  else
2100 	    temp = FALSE;
2101 
2102 	  xtensa_hard_regno_mode_ok[(int) mode][regno] = temp;
2103 	}
2104     }
2105 
2106   init_machine_status = xtensa_init_machine_status;
2107 
2108   /* Check PIC settings.  PIC is only supported when using L32R
2109      instructions, and some targets need to always use PIC.  */
2110   if (flag_pic && TARGET_CONST16)
2111     error ("-f%s is not supported with CONST16 instructions",
2112 	   (flag_pic > 1 ? "PIC" : "pic"));
2113   else if (XTENSA_ALWAYS_PIC)
2114     {
2115       if (TARGET_CONST16)
2116 	error ("PIC is required but not supported with CONST16 instructions");
2117       flag_pic = 1;
2118     }
2119   /* There's no need for -fPIC (as opposed to -fpic) on Xtensa.  */
2120   if (flag_pic > 1)
2121     flag_pic = 1;
2122   if (flag_pic && !flag_pie)
2123     flag_shlib = 1;
2124 
2125   /* Hot/cold partitioning does not work on this architecture, because of
2126      constant pools (the load instruction cannot necessarily reach that far).
2127      Therefore disable it on this architecture.  */
2128   if (flag_reorder_blocks_and_partition)
2129     {
2130       flag_reorder_blocks_and_partition = 0;
2131       flag_reorder_blocks = 1;
2132     }
2133 }
2134 
2135 
2136 /* A C compound statement to output to stdio stream STREAM the
2137    assembler syntax for an instruction operand X.  X is an RTL
2138    expression.
2139 
2140    CODE is a value that can be used to specify one of several ways
2141    of printing the operand.  It is used when identical operands
2142    must be printed differently depending on the context.  CODE
2143    comes from the '%' specification that was used to request
2144    printing of the operand.  If the specification was just '%DIGIT'
2145    then CODE is 0; if the specification was '%LTR DIGIT' then CODE
2146    is the ASCII code for LTR.
2147 
2148    If X is a register, this macro should print the register's name.
2149    The names can be found in an array 'reg_names' whose type is
2150    'char *[]'.  'reg_names' is initialized from 'REGISTER_NAMES'.
2151 
2152    When the machine description has a specification '%PUNCT' (a '%'
2153    followed by a punctuation character), this macro is called with
2154    a null pointer for X and the punctuation character for CODE.
2155 
2156    'a', 'c', 'l', and 'n' are reserved.
2157 
2158    The Xtensa specific codes are:
2159 
2160    'd'  CONST_INT, print as signed decimal
2161    'x'  CONST_INT, print as signed hexadecimal
2162    'K'  CONST_INT, print number of bits in mask for EXTUI
2163    'R'  CONST_INT, print (X & 0x1f)
2164    'L'  CONST_INT, print ((32 - X) & 0x1f)
2165    'D'  REG, print second register of double-word register operand
2166    'N'  MEM, print address of next word following a memory operand
2167    'v'  MEM, if memory reference is volatile, output a MEMW before it
2168    't'  any constant, add "@h" suffix for top 16 bits
2169    'b'  any constant, add "@l" suffix for bottom 16 bits
2170 */
2171 
2172 static void
2173 printx (FILE *file, signed int val)
2174 {
2175   /* Print a hexadecimal value in a nice way.  */
2176   if ((val > -0xa) && (val < 0xa))
2177     fprintf (file, "%d", val);
2178   else if (val < 0)
2179     fprintf (file, "-0x%x", -val);
2180   else
2181     fprintf (file, "0x%x", val);
2182 }
2183 
2184 
2185 void
2186 print_operand (FILE *file, rtx x, int letter)
2187 {
2188   if (!x)
2189     error ("PRINT_OPERAND null pointer");
2190 
2191   switch (letter)
2192     {
2193     case 'D':
2194       if (GET_CODE (x) == REG || GET_CODE (x) == SUBREG)
2195 	fprintf (file, "%s", reg_names[xt_true_regnum (x) + 1]);
2196       else
2197 	output_operand_lossage ("invalid %%D value");
2198       break;
2199 
2200     case 'v':
2201       if (GET_CODE (x) == MEM)
2202 	{
2203 	  /* For a volatile memory reference, emit a MEMW before the
2204 	     load or store.  */
2205 	  if (MEM_VOLATILE_P (x) && TARGET_SERIALIZE_VOLATILE)
2206 	    fprintf (file, "memw\n\t");
2207 	}
2208       else
2209 	output_operand_lossage ("invalid %%v value");
2210       break;
2211 
2212     case 'N':
2213       if (GET_CODE (x) == MEM
2214 	  && (GET_MODE (x) == DFmode || GET_MODE (x) == DImode))
2215 	{
2216 	  x = adjust_address (x, GET_MODE (x) == DFmode ? SFmode : SImode, 4);
2217 	  output_address (XEXP (x, 0));
2218 	}
2219       else
2220 	output_operand_lossage ("invalid %%N value");
2221       break;
2222 
2223     case 'K':
2224       if (GET_CODE (x) == CONST_INT)
2225 	{
2226 	  int num_bits = 0;
2227 	  unsigned val = INTVAL (x);
2228 	  while (val & 1)
2229 	    {
2230 	      num_bits += 1;
2231 	      val = val >> 1;
2232 	    }
2233 	  if ((val != 0) || (num_bits == 0) || (num_bits > 16))
2234 	    fatal_insn ("invalid mask", x);
2235 
2236 	  fprintf (file, "%d", num_bits);
2237 	}
2238       else
2239 	output_operand_lossage ("invalid %%K value");
2240       break;
2241 
2242     case 'L':
2243       if (GET_CODE (x) == CONST_INT)
2244 	fprintf (file, "%ld", (32 - INTVAL (x)) & 0x1f);
2245       else
2246 	output_operand_lossage ("invalid %%L value");
2247       break;
2248 
2249     case 'R':
2250       if (GET_CODE (x) == CONST_INT)
2251 	fprintf (file, "%ld", INTVAL (x) & 0x1f);
2252       else
2253 	output_operand_lossage ("invalid %%R value");
2254       break;
2255 
2256     case 'x':
2257       if (GET_CODE (x) == CONST_INT)
2258 	printx (file, INTVAL (x));
2259       else
2260 	output_operand_lossage ("invalid %%x value");
2261       break;
2262 
2263     case 'd':
2264       if (GET_CODE (x) == CONST_INT)
2265 	fprintf (file, "%ld", INTVAL (x));
2266       else
2267 	output_operand_lossage ("invalid %%d value");
2268       break;
2269 
2270     case 't':
2271     case 'b':
2272       if (GET_CODE (x) == CONST_INT)
2273 	{
2274 	  printx (file, INTVAL (x));
2275 	  fputs (letter == 't' ? "@h" : "@l", file);
2276 	}
2277       else if (GET_CODE (x) == CONST_DOUBLE)
2278 	{
2279 	  REAL_VALUE_TYPE r;
2280 	  REAL_VALUE_FROM_CONST_DOUBLE (r, x);
2281 	  if (GET_MODE (x) == SFmode)
2282 	    {
2283 	      long l;
2284 	      REAL_VALUE_TO_TARGET_SINGLE (r, l);
2285 	      fprintf (file, "0x%08lx@%c", l, letter == 't' ? 'h' : 'l');
2286 	    }
2287 	  else
2288 	    output_operand_lossage ("invalid %%t/%%b value");
2289 	}
2290       else if (GET_CODE (x) == CONST)
2291 	{
2292 	  /* X must be a symbolic constant on ELF.  Write an expression
2293 	     suitable for 'const16' that sets the high or low 16 bits.  */
2294 	  if (GET_CODE (XEXP (x, 0)) != PLUS
2295 	      || (GET_CODE (XEXP (XEXP (x, 0), 0)) != SYMBOL_REF
2296 		  && GET_CODE (XEXP (XEXP (x, 0), 0)) != LABEL_REF)
2297 	      || GET_CODE (XEXP (XEXP (x, 0), 1)) != CONST_INT)
2298 	    output_operand_lossage ("invalid %%t/%%b value");
2299 	  print_operand (file, XEXP (XEXP (x, 0), 0), 0);
2300 	  fputs (letter == 't' ? "@h" : "@l", file);
2301 	  /* There must be a non-alphanumeric character between 'h' or 'l'
2302 	     and the number.  The '-' is added by print_operand() already.  */
2303 	  if (INTVAL (XEXP (XEXP (x, 0), 1)) >= 0)
2304 	    fputs ("+", file);
2305 	  print_operand (file, XEXP (XEXP (x, 0), 1), 0);
2306 	}
2307       else
2308 	{
2309 	  output_addr_const (file, x);
2310 	  fputs (letter == 't' ? "@h" : "@l", file);
2311 	}
2312       break;
2313 
2314     default:
2315       if (GET_CODE (x) == REG || GET_CODE (x) == SUBREG)
2316 	fprintf (file, "%s", reg_names[xt_true_regnum (x)]);
2317       else if (GET_CODE (x) == MEM)
2318 	output_address (XEXP (x, 0));
2319       else if (GET_CODE (x) == CONST_INT)
2320 	fprintf (file, "%ld", INTVAL (x));
2321       else
2322 	output_addr_const (file, x);
2323     }
2324 }
2325 
2326 
2327 /* A C compound statement to output to stdio stream STREAM the
2328    assembler syntax for an instruction operand that is a memory
2329    reference whose address is ADDR.  ADDR is an RTL expression.  */
2330 
2331 void
2332 print_operand_address (FILE *file, rtx addr)
2333 {
2334   if (!addr)
2335     error ("PRINT_OPERAND_ADDRESS, null pointer");
2336 
2337   switch (GET_CODE (addr))
2338     {
2339     default:
2340       fatal_insn ("invalid address", addr);
2341       break;
2342 
2343     case REG:
2344       fprintf (file, "%s, 0", reg_names [REGNO (addr)]);
2345       break;
2346 
2347     case PLUS:
2348       {
2349 	rtx reg = (rtx)0;
2350 	rtx offset = (rtx)0;
2351 	rtx arg0 = XEXP (addr, 0);
2352 	rtx arg1 = XEXP (addr, 1);
2353 
2354 	if (GET_CODE (arg0) == REG)
2355 	  {
2356 	    reg = arg0;
2357 	    offset = arg1;
2358 	  }
2359 	else if (GET_CODE (arg1) == REG)
2360 	  {
2361 	    reg = arg1;
2362 	    offset = arg0;
2363 	  }
2364 	else
2365 	  fatal_insn ("no register in address", addr);
2366 
2367 	if (CONSTANT_P (offset))
2368 	  {
2369 	    fprintf (file, "%s, ", reg_names [REGNO (reg)]);
2370 	    output_addr_const (file, offset);
2371 	  }
2372 	else
2373 	  fatal_insn ("address offset not a constant", addr);
2374       }
2375       break;
2376 
2377     case LABEL_REF:
2378     case SYMBOL_REF:
2379     case CONST_INT:
2380     case CONST:
2381       output_addr_const (file, addr);
2382       break;
2383     }
2384 }
2385 
2386 
2387 bool
2388 xtensa_output_addr_const_extra (FILE *fp, rtx x)
2389 {
2390   if (GET_CODE (x) == UNSPEC && XVECLEN (x, 0) == 1)
2391     {
2392       switch (XINT (x, 1))
2393 	{
2394 	case UNSPEC_TPOFF:
2395 	  output_addr_const (fp, XVECEXP (x, 0, 0));
2396 	  fputs ("@TPOFF", fp);
2397 	  return true;
2398 	case UNSPEC_DTPOFF:
2399 	  output_addr_const (fp, XVECEXP (x, 0, 0));
2400 	  fputs ("@DTPOFF", fp);
2401 	  return true;
2402 	case UNSPEC_PLT:
2403 	  if (flag_pic)
2404 	    {
2405 	      output_addr_const (fp, XVECEXP (x, 0, 0));
2406 	      fputs ("@PLT", fp);
2407 	      return true;
2408 	    }
2409 	  break;
2410 	default:
2411 	  break;
2412 	}
2413     }
2414   return false;
2415 }
2416 
2417 
2418 void
2419 xtensa_output_literal (FILE *file, rtx x, enum machine_mode mode, int labelno)
2420 {
2421   long value_long[2];
2422   REAL_VALUE_TYPE r;
2423   int size;
2424   rtx first, second;
2425 
2426   fprintf (file, "\t.literal .LC%u, ", (unsigned) labelno);
2427 
2428   switch (GET_MODE_CLASS (mode))
2429     {
2430     case MODE_FLOAT:
2431       gcc_assert (GET_CODE (x) == CONST_DOUBLE);
2432 
2433       REAL_VALUE_FROM_CONST_DOUBLE (r, x);
2434       switch (mode)
2435 	{
2436 	case SFmode:
2437 	  REAL_VALUE_TO_TARGET_SINGLE (r, value_long[0]);
2438 	  if (HOST_BITS_PER_LONG > 32)
2439 	    value_long[0] &= 0xffffffff;
2440 	  fprintf (file, "0x%08lx\n", value_long[0]);
2441 	  break;
2442 
2443 	case DFmode:
2444 	  REAL_VALUE_TO_TARGET_DOUBLE (r, value_long);
2445 	  if (HOST_BITS_PER_LONG > 32)
2446 	    {
2447 	      value_long[0] &= 0xffffffff;
2448 	      value_long[1] &= 0xffffffff;
2449 	    }
2450 	  fprintf (file, "0x%08lx, 0x%08lx\n",
2451 		   value_long[0], value_long[1]);
2452 	  break;
2453 
2454 	default:
2455 	  gcc_unreachable ();
2456 	}
2457 
2458       break;
2459 
2460     case MODE_INT:
2461     case MODE_PARTIAL_INT:
2462       size = GET_MODE_SIZE (mode);
2463       switch (size)
2464 	{
2465 	case 4:
2466 	  output_addr_const (file, x);
2467 	  fputs ("\n", file);
2468 	  break;
2469 
2470 	case 8:
2471 	  split_double (x, &first, &second);
2472 	  output_addr_const (file, first);
2473 	  fputs (", ", file);
2474 	  output_addr_const (file, second);
2475 	  fputs ("\n", file);
2476 	  break;
2477 
2478 	default:
2479 	  gcc_unreachable ();
2480 	}
2481       break;
2482 
2483     default:
2484       gcc_unreachable ();
2485     }
2486 }
2487 
2488 
2489 /* Return the bytes needed to compute the frame pointer from the current
2490    stack pointer.  */
2491 
2492 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
2493 #define XTENSA_STACK_ALIGN(LOC) (((LOC) + STACK_BYTES-1) & ~(STACK_BYTES-1))
2494 
2495 long
2496 compute_frame_size (int size)
2497 {
2498   /* Add space for the incoming static chain value.  */
2499   if (cfun->static_chain_decl != NULL)
2500     size += (1 * UNITS_PER_WORD);
2501 
2502   xtensa_current_frame_size =
2503     XTENSA_STACK_ALIGN (size
2504 			+ crtl->outgoing_args_size
2505 			+ (WINDOW_SIZE * UNITS_PER_WORD));
2506   return xtensa_current_frame_size;
2507 }
2508 
2509 
2510 bool
2511 xtensa_frame_pointer_required (void)
2512 {
2513   /* The code to expand builtin_frame_addr and builtin_return_addr
2514      currently uses the hard_frame_pointer instead of frame_pointer.
2515      This seems wrong but maybe it's necessary for other architectures.
2516      This function is derived from the i386 code.  */
2517 
2518   if (cfun->machine->accesses_prev_frame)
2519     return true;
2520 
2521   return false;
2522 }
2523 
2524 
2525 /* minimum frame = reg save area (4 words) plus static chain (1 word)
2526    and the total number of words must be a multiple of 128 bits.  */
2527 #define MIN_FRAME_SIZE (8 * UNITS_PER_WORD)
2528 
2529 void
2530 xtensa_expand_prologue (void)
2531 {
2532   HOST_WIDE_INT total_size;
2533   rtx size_rtx;
2534   rtx insn, note_rtx;
2535 
2536   total_size = compute_frame_size (get_frame_size ());
2537   size_rtx = GEN_INT (total_size);
2538 
2539   if (total_size < (1 << (12+3)))
2540     insn = emit_insn (gen_entry (size_rtx));
2541   else
2542     {
2543       /* Use a8 as a temporary since a0-a7 may be live.  */
2544       rtx tmp_reg = gen_rtx_REG (Pmode, A8_REG);
2545       emit_insn (gen_entry (GEN_INT (MIN_FRAME_SIZE)));
2546       emit_move_insn (tmp_reg, GEN_INT (total_size - MIN_FRAME_SIZE));
2547       emit_insn (gen_subsi3 (tmp_reg, stack_pointer_rtx, tmp_reg));
2548       insn = emit_insn (gen_movsi (stack_pointer_rtx, tmp_reg));
2549     }
2550 
2551   if (frame_pointer_needed)
2552     {
2553       if (cfun->machine->set_frame_ptr_insn)
2554 	{
2555 	  rtx first;
2556 
2557 	  push_topmost_sequence ();
2558 	  first = get_insns ();
2559 	  pop_topmost_sequence ();
2560 
2561 	  /* For all instructions prior to set_frame_ptr_insn, replace
2562 	     hard_frame_pointer references with stack_pointer.  */
2563 	  for (insn = first;
2564 	       insn != cfun->machine->set_frame_ptr_insn;
2565 	       insn = NEXT_INSN (insn))
2566 	    {
2567 	      if (INSN_P (insn))
2568 		{
2569 		  PATTERN (insn) = replace_rtx (copy_rtx (PATTERN (insn)),
2570 						hard_frame_pointer_rtx,
2571 						stack_pointer_rtx);
2572 		  df_insn_rescan (insn);
2573 		}
2574 	    }
2575 	}
2576       else
2577 	insn = emit_insn (gen_movsi (hard_frame_pointer_rtx,
2578 				     stack_pointer_rtx));
2579     }
2580 
2581   /* Create a note to describe the CFA.  Because this is only used to set
2582      DW_AT_frame_base for debug info, don't bother tracking changes through
2583      each instruction in the prologue.  It just takes up space.  */
2584   note_rtx = gen_rtx_SET (VOIDmode, (frame_pointer_needed
2585 				     ? hard_frame_pointer_rtx
2586 				     : stack_pointer_rtx),
2587 			  plus_constant (stack_pointer_rtx, -total_size));
2588   RTX_FRAME_RELATED_P (insn) = 1;
2589   REG_NOTES (insn) = gen_rtx_EXPR_LIST (REG_FRAME_RELATED_EXPR,
2590 					note_rtx, REG_NOTES (insn));
2591 }
2592 
2593 
2594 /* Clear variables at function end.  */
2595 
2596 void
2597 xtensa_function_epilogue (FILE *file ATTRIBUTE_UNUSED,
2598 			  HOST_WIDE_INT size ATTRIBUTE_UNUSED)
2599 {
2600   xtensa_current_frame_size = 0;
2601 }
2602 
2603 
2604 rtx
2605 xtensa_return_addr (int count, rtx frame)
2606 {
2607   rtx result, retaddr, curaddr, label;
2608 
2609   if (count == -1)
2610     retaddr = gen_rtx_REG (Pmode, A0_REG);
2611   else
2612     {
2613       rtx addr = plus_constant (frame, -4 * UNITS_PER_WORD);
2614       addr = memory_address (Pmode, addr);
2615       retaddr = gen_reg_rtx (Pmode);
2616       emit_move_insn (retaddr, gen_rtx_MEM (Pmode, addr));
2617     }
2618 
2619   /* The 2 most-significant bits of the return address on Xtensa hold
2620      the register window size.  To get the real return address, these
2621      bits must be replaced with the high bits from some address in the
2622      code.  */
2623 
2624   /* Get the 2 high bits of a local label in the code.  */
2625   curaddr = gen_reg_rtx (Pmode);
2626   label = gen_label_rtx ();
2627   emit_label (label);
2628   LABEL_PRESERVE_P (label) = 1;
2629   emit_move_insn (curaddr, gen_rtx_LABEL_REF (Pmode, label));
2630   emit_insn (gen_lshrsi3 (curaddr, curaddr, GEN_INT (30)));
2631   emit_insn (gen_ashlsi3 (curaddr, curaddr, GEN_INT (30)));
2632 
2633   /* Clear the 2 high bits of the return address.  */
2634   result = gen_reg_rtx (Pmode);
2635   emit_insn (gen_ashlsi3 (result, retaddr, GEN_INT (2)));
2636   emit_insn (gen_lshrsi3 (result, result, GEN_INT (2)));
2637 
2638   /* Combine them to get the result.  */
2639   emit_insn (gen_iorsi3 (result, result, curaddr));
2640   return result;
2641 }
2642 
2643 
2644 /* Create the va_list data type.
2645 
2646    This structure is set up by __builtin_saveregs.  The __va_reg field
2647    points to a stack-allocated region holding the contents of the
2648    incoming argument registers.  The __va_ndx field is an index
2649    initialized to the position of the first unnamed (variable)
2650    argument.  This same index is also used to address the arguments
2651    passed in memory.  Thus, the __va_stk field is initialized to point
2652    to the position of the first argument in memory offset to account
2653    for the arguments passed in registers and to account for the size
2654    of the argument registers not being 16-byte aligned.  E.G., there
2655    are 6 argument registers of 4 bytes each, but we want the __va_ndx
2656    for the first stack argument to have the maximal alignment of 16
2657    bytes, so we offset the __va_stk address by 32 bytes so that
2658    __va_stk[32] references the first argument on the stack.  */
2659 
2660 static tree
2661 xtensa_build_builtin_va_list (void)
2662 {
2663   tree f_stk, f_reg, f_ndx, record, type_decl;
2664 
2665   record = (*lang_hooks.types.make_type) (RECORD_TYPE);
2666   type_decl = build_decl (BUILTINS_LOCATION,
2667 			  TYPE_DECL, get_identifier ("__va_list_tag"), record);
2668 
2669   f_stk = build_decl (BUILTINS_LOCATION,
2670 		      FIELD_DECL, get_identifier ("__va_stk"),
2671 		      ptr_type_node);
2672   f_reg = build_decl (BUILTINS_LOCATION,
2673 		      FIELD_DECL, get_identifier ("__va_reg"),
2674 		      ptr_type_node);
2675   f_ndx = build_decl (BUILTINS_LOCATION,
2676 		      FIELD_DECL, get_identifier ("__va_ndx"),
2677 		      integer_type_node);
2678 
2679   DECL_FIELD_CONTEXT (f_stk) = record;
2680   DECL_FIELD_CONTEXT (f_reg) = record;
2681   DECL_FIELD_CONTEXT (f_ndx) = record;
2682 
2683   TREE_CHAIN (record) = type_decl;
2684   TYPE_NAME (record) = type_decl;
2685   TYPE_FIELDS (record) = f_stk;
2686   TREE_CHAIN (f_stk) = f_reg;
2687   TREE_CHAIN (f_reg) = f_ndx;
2688 
2689   layout_type (record);
2690   return record;
2691 }
2692 
2693 
2694 /* Save the incoming argument registers on the stack.  Returns the
2695    address of the saved registers.  */
2696 
2697 static rtx
2698 xtensa_builtin_saveregs (void)
2699 {
2700   rtx gp_regs;
2701   int arg_words = crtl->args.info.arg_words;
2702   int gp_left = MAX_ARGS_IN_REGISTERS - arg_words;
2703 
2704   if (gp_left <= 0)
2705     return const0_rtx;
2706 
2707   /* Allocate the general-purpose register space.  */
2708   gp_regs = assign_stack_local
2709     (BLKmode, MAX_ARGS_IN_REGISTERS * UNITS_PER_WORD, -1);
2710   set_mem_alias_set (gp_regs, get_varargs_alias_set ());
2711 
2712   /* Now store the incoming registers.  */
2713   cfun->machine->need_a7_copy = true;
2714   cfun->machine->vararg_a7 = true;
2715   move_block_from_reg (GP_ARG_FIRST + arg_words,
2716 		       adjust_address (gp_regs, BLKmode,
2717 				       arg_words * UNITS_PER_WORD),
2718 		       gp_left);
2719   gcc_assert (cfun->machine->vararg_a7_copy != 0);
2720   emit_insn_before (cfun->machine->vararg_a7_copy, get_insns ());
2721 
2722   return XEXP (gp_regs, 0);
2723 }
2724 
2725 
2726 /* Implement `va_start' for varargs and stdarg.  We look at the
2727    current function to fill in an initial va_list.  */
2728 
2729 static void
2730 xtensa_va_start (tree valist, rtx nextarg ATTRIBUTE_UNUSED)
2731 {
2732   tree f_stk, stk;
2733   tree f_reg, reg;
2734   tree f_ndx, ndx;
2735   tree t, u;
2736   int arg_words;
2737 
2738   arg_words = crtl->args.info.arg_words;
2739 
2740   f_stk = TYPE_FIELDS (va_list_type_node);
2741   f_reg = TREE_CHAIN (f_stk);
2742   f_ndx = TREE_CHAIN (f_reg);
2743 
2744   stk = build3 (COMPONENT_REF, TREE_TYPE (f_stk), valist, f_stk, NULL_TREE);
2745   reg = build3 (COMPONENT_REF, TREE_TYPE (f_reg), unshare_expr (valist),
2746 		f_reg, NULL_TREE);
2747   ndx = build3 (COMPONENT_REF, TREE_TYPE (f_ndx), unshare_expr (valist),
2748 		f_ndx, NULL_TREE);
2749 
2750   /* Call __builtin_saveregs; save the result in __va_reg */
2751   u = make_tree (sizetype, expand_builtin_saveregs ());
2752   u = fold_convert (ptr_type_node, u);
2753   t = build2 (MODIFY_EXPR, ptr_type_node, reg, u);
2754   TREE_SIDE_EFFECTS (t) = 1;
2755   expand_expr (t, const0_rtx, VOIDmode, EXPAND_NORMAL);
2756 
2757   /* Set the __va_stk member to ($arg_ptr - 32).  */
2758   u = make_tree (ptr_type_node, virtual_incoming_args_rtx);
2759   u = fold_build2 (POINTER_PLUS_EXPR, ptr_type_node, u, size_int (-32));
2760   t = build2 (MODIFY_EXPR, ptr_type_node, stk, u);
2761   TREE_SIDE_EFFECTS (t) = 1;
2762   expand_expr (t, const0_rtx, VOIDmode, EXPAND_NORMAL);
2763 
2764   /* Set the __va_ndx member.  If the first variable argument is on
2765      the stack, adjust __va_ndx by 2 words to account for the extra
2766      alignment offset for __va_stk.  */
2767   if (arg_words >= MAX_ARGS_IN_REGISTERS)
2768     arg_words += 2;
2769   t = build2 (MODIFY_EXPR, integer_type_node, ndx,
2770 	      build_int_cst (integer_type_node, arg_words * UNITS_PER_WORD));
2771   TREE_SIDE_EFFECTS (t) = 1;
2772   expand_expr (t, const0_rtx, VOIDmode, EXPAND_NORMAL);
2773 }
2774 
2775 
2776 /* Implement `va_arg'.  */
2777 
2778 static tree
2779 xtensa_gimplify_va_arg_expr (tree valist, tree type, gimple_seq *pre_p,
2780 			     gimple_seq *post_p ATTRIBUTE_UNUSED)
2781 {
2782   tree f_stk, stk;
2783   tree f_reg, reg;
2784   tree f_ndx, ndx;
2785   tree type_size, array, orig_ndx, addr, size, va_size, t;
2786   tree lab_false, lab_over, lab_false2;
2787   bool indirect;
2788 
2789   indirect = pass_by_reference (NULL, TYPE_MODE (type), type, false);
2790   if (indirect)
2791     type = build_pointer_type (type);
2792 
2793   /* Handle complex values as separate real and imaginary parts.  */
2794   if (TREE_CODE (type) == COMPLEX_TYPE)
2795     {
2796       tree real_part, imag_part;
2797 
2798       real_part = xtensa_gimplify_va_arg_expr (valist, TREE_TYPE (type),
2799 					       pre_p, NULL);
2800       real_part = get_initialized_tmp_var (real_part, pre_p, NULL);
2801 
2802       imag_part = xtensa_gimplify_va_arg_expr (unshare_expr (valist),
2803 					       TREE_TYPE (type),
2804 					       pre_p, NULL);
2805       imag_part = get_initialized_tmp_var (imag_part, pre_p, NULL);
2806 
2807       return build2 (COMPLEX_EXPR, type, real_part, imag_part);
2808     }
2809 
2810   f_stk = TYPE_FIELDS (va_list_type_node);
2811   f_reg = TREE_CHAIN (f_stk);
2812   f_ndx = TREE_CHAIN (f_reg);
2813 
2814   stk = build3 (COMPONENT_REF, TREE_TYPE (f_stk), valist,
2815 		f_stk, NULL_TREE);
2816   reg = build3 (COMPONENT_REF, TREE_TYPE (f_reg), unshare_expr (valist),
2817 		f_reg, NULL_TREE);
2818   ndx = build3 (COMPONENT_REF, TREE_TYPE (f_ndx), unshare_expr (valist),
2819 		f_ndx, NULL_TREE);
2820 
2821   type_size = size_in_bytes (type);
2822   va_size = round_up (type_size, UNITS_PER_WORD);
2823   gimplify_expr (&va_size, pre_p, NULL, is_gimple_val, fb_rvalue);
2824 
2825 
2826   /* First align __va_ndx if necessary for this arg:
2827 
2828      orig_ndx = (AP).__va_ndx;
2829      if (__alignof__ (TYPE) > 4 )
2830        orig_ndx = ((orig_ndx + __alignof__ (TYPE) - 1)
2831 			& -__alignof__ (TYPE)); */
2832 
2833   orig_ndx = get_initialized_tmp_var (ndx, pre_p, NULL);
2834 
2835   if (TYPE_ALIGN (type) > BITS_PER_WORD)
2836     {
2837       int align = MIN (TYPE_ALIGN (type), STACK_BOUNDARY) / BITS_PER_UNIT;
2838 
2839       t = build2 (PLUS_EXPR, integer_type_node, unshare_expr (orig_ndx),
2840 		  build_int_cst (integer_type_node, align - 1));
2841       t = build2 (BIT_AND_EXPR, integer_type_node, t,
2842 		  build_int_cst (integer_type_node, -align));
2843       gimplify_assign (unshare_expr (orig_ndx), t, pre_p);
2844     }
2845 
2846 
2847   /* Increment __va_ndx to point past the argument:
2848 
2849      (AP).__va_ndx = orig_ndx + __va_size (TYPE); */
2850 
2851   t = fold_convert (integer_type_node, va_size);
2852   t = build2 (PLUS_EXPR, integer_type_node, orig_ndx, t);
2853   gimplify_assign (unshare_expr (ndx), t, pre_p);
2854 
2855 
2856   /* Check if the argument is in registers:
2857 
2858      if ((AP).__va_ndx <= __MAX_ARGS_IN_REGISTERS * 4
2859          && !must_pass_in_stack (type))
2860         __array = (AP).__va_reg; */
2861 
2862   array = create_tmp_var (ptr_type_node, NULL);
2863 
2864   lab_over = NULL;
2865   if (!targetm.calls.must_pass_in_stack (TYPE_MODE (type), type))
2866     {
2867       lab_false = create_artificial_label (UNKNOWN_LOCATION);
2868       lab_over = create_artificial_label (UNKNOWN_LOCATION);
2869 
2870       t = build2 (GT_EXPR, boolean_type_node, unshare_expr (ndx),
2871 		  build_int_cst (integer_type_node,
2872 				 MAX_ARGS_IN_REGISTERS * UNITS_PER_WORD));
2873       t = build3 (COND_EXPR, void_type_node, t,
2874 		  build1 (GOTO_EXPR, void_type_node, lab_false),
2875 		  NULL_TREE);
2876       gimplify_and_add (t, pre_p);
2877 
2878       gimplify_assign (unshare_expr (array), reg, pre_p);
2879 
2880       t = build1 (GOTO_EXPR, void_type_node, lab_over);
2881       gimplify_and_add (t, pre_p);
2882 
2883       t = build1 (LABEL_EXPR, void_type_node, lab_false);
2884       gimplify_and_add (t, pre_p);
2885     }
2886 
2887 
2888   /* ...otherwise, the argument is on the stack (never split between
2889      registers and the stack -- change __va_ndx if necessary):
2890 
2891      else
2892        {
2893 	 if (orig_ndx <= __MAX_ARGS_IN_REGISTERS * 4)
2894 	     (AP).__va_ndx = 32 + __va_size (TYPE);
2895 	 __array = (AP).__va_stk;
2896        } */
2897 
2898   lab_false2 = create_artificial_label (UNKNOWN_LOCATION);
2899 
2900   t = build2 (GT_EXPR, boolean_type_node, unshare_expr (orig_ndx),
2901 	      build_int_cst (integer_type_node,
2902 			     MAX_ARGS_IN_REGISTERS * UNITS_PER_WORD));
2903   t = build3 (COND_EXPR, void_type_node, t,
2904 	      build1 (GOTO_EXPR, void_type_node, lab_false2),
2905 	      NULL_TREE);
2906   gimplify_and_add (t, pre_p);
2907 
2908   t = size_binop (PLUS_EXPR, unshare_expr (va_size), size_int (32));
2909   t = fold_convert (integer_type_node, t);
2910   gimplify_assign (unshare_expr (ndx), t, pre_p);
2911 
2912   t = build1 (LABEL_EXPR, void_type_node, lab_false2);
2913   gimplify_and_add (t, pre_p);
2914 
2915   gimplify_assign (array, stk, pre_p);
2916 
2917   if (lab_over)
2918     {
2919       t = build1 (LABEL_EXPR, void_type_node, lab_over);
2920       gimplify_and_add (t, pre_p);
2921     }
2922 
2923 
2924   /* Given the base array pointer (__array) and index to the subsequent
2925      argument (__va_ndx), find the address:
2926 
2927      __array + (AP).__va_ndx - (BYTES_BIG_ENDIAN && sizeof (TYPE) < 4
2928 				? sizeof (TYPE)
2929 				: __va_size (TYPE))
2930 
2931      The results are endian-dependent because values smaller than one word
2932      are aligned differently.  */
2933 
2934 
2935   if (BYTES_BIG_ENDIAN && TREE_CODE (type_size) == INTEGER_CST)
2936     {
2937       t = fold_build2 (GE_EXPR, boolean_type_node, unshare_expr (type_size),
2938 		       size_int (PARM_BOUNDARY / BITS_PER_UNIT));
2939       t = fold_build3 (COND_EXPR, sizetype, t, unshare_expr (va_size),
2940 		       unshare_expr (type_size));
2941       size = t;
2942     }
2943   else
2944     size = unshare_expr (va_size);
2945 
2946   t = fold_convert (sizetype, unshare_expr (ndx));
2947   t = build2 (MINUS_EXPR, sizetype, t, size);
2948   addr = build2 (POINTER_PLUS_EXPR, ptr_type_node, unshare_expr (array), t);
2949 
2950   addr = fold_convert (build_pointer_type (type), addr);
2951   if (indirect)
2952     addr = build_va_arg_indirect_ref (addr);
2953   return build_va_arg_indirect_ref (addr);
2954 }
2955 
2956 
2957 /* Builtins.  */
2958 
2959 enum xtensa_builtin
2960 {
2961   XTENSA_BUILTIN_UMULSIDI3,
2962   XTENSA_BUILTIN_THREAD_POINTER,
2963   XTENSA_BUILTIN_SET_THREAD_POINTER,
2964   XTENSA_BUILTIN_max
2965 };
2966 
2967 
2968 static void
2969 xtensa_init_builtins (void)
2970 {
2971   tree ftype, decl;
2972 
2973   ftype = build_function_type_list (unsigned_intDI_type_node,
2974 				    unsigned_intSI_type_node,
2975 				    unsigned_intSI_type_node, NULL_TREE);
2976 
2977   decl = add_builtin_function ("__builtin_umulsidi3", ftype,
2978 			       XTENSA_BUILTIN_UMULSIDI3, BUILT_IN_MD,
2979 			       "__umulsidi3", NULL_TREE);
2980   TREE_NOTHROW (decl) = 1;
2981   TREE_READONLY (decl) = 1;
2982 
2983   if (TARGET_THREADPTR)
2984     {
2985       ftype = build_function_type (ptr_type_node, void_list_node);
2986       decl = add_builtin_function ("__builtin_thread_pointer", ftype,
2987 				   XTENSA_BUILTIN_THREAD_POINTER, BUILT_IN_MD,
2988 				   NULL, NULL_TREE);
2989       TREE_READONLY (decl) = 1;
2990       TREE_NOTHROW (decl) = 1;
2991 
2992       ftype = build_function_type_list (void_type_node, ptr_type_node,
2993 					NULL_TREE);
2994       decl = add_builtin_function ("__builtin_set_thread_pointer", ftype,
2995 				   XTENSA_BUILTIN_SET_THREAD_POINTER,
2996 				   BUILT_IN_MD, NULL, NULL_TREE);
2997       TREE_NOTHROW (decl) = 1;
2998     }
2999 }
3000 
3001 
3002 static tree
3003 xtensa_fold_builtin (tree fndecl, tree arglist, bool ignore ATTRIBUTE_UNUSED)
3004 {
3005   unsigned int fcode = DECL_FUNCTION_CODE (fndecl);
3006   tree arg0, arg1;
3007 
3008   switch (fcode)
3009     {
3010     case XTENSA_BUILTIN_UMULSIDI3:
3011       arg0 = TREE_VALUE (arglist);
3012       arg1 = TREE_VALUE (TREE_CHAIN (arglist));
3013       if ((TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
3014 	  || TARGET_MUL32_HIGH)
3015 	return fold_build2 (MULT_EXPR, unsigned_intDI_type_node,
3016 			    fold_convert (unsigned_intDI_type_node, arg0),
3017 			    fold_convert (unsigned_intDI_type_node, arg1));
3018       break;
3019 
3020     case XTENSA_BUILTIN_THREAD_POINTER:
3021     case XTENSA_BUILTIN_SET_THREAD_POINTER:
3022       break;
3023 
3024     default:
3025       internal_error ("bad builtin code");
3026       break;
3027     }
3028 
3029   return NULL;
3030 }
3031 
3032 
3033 static rtx
3034 xtensa_expand_builtin (tree exp, rtx target,
3035 		       rtx subtarget ATTRIBUTE_UNUSED,
3036 		       enum machine_mode mode ATTRIBUTE_UNUSED,
3037 		       int ignore)
3038 {
3039   tree fndecl = TREE_OPERAND (CALL_EXPR_FN (exp), 0);
3040   unsigned int fcode = DECL_FUNCTION_CODE (fndecl);
3041   rtx arg;
3042 
3043   switch (fcode)
3044     {
3045     case XTENSA_BUILTIN_UMULSIDI3:
3046       /* The umulsidi3 builtin is just a mechanism to avoid calling the real
3047 	 __umulsidi3 function when the Xtensa configuration can directly
3048 	 implement it.  If not, just call the function.  */
3049       return expand_call (exp, target, ignore);
3050 
3051     case XTENSA_BUILTIN_THREAD_POINTER:
3052       if (!target || !register_operand (target, Pmode))
3053 	target = gen_reg_rtx (Pmode);
3054       emit_insn (gen_load_tp (target));
3055       return target;
3056 
3057     case XTENSA_BUILTIN_SET_THREAD_POINTER:
3058       arg = expand_normal (CALL_EXPR_ARG (exp, 0));
3059       if (!register_operand (arg, Pmode))
3060 	arg = copy_to_mode_reg (Pmode, arg);
3061       emit_insn (gen_set_tp (arg));
3062       return const0_rtx;
3063 
3064     default:
3065       internal_error ("bad builtin code");
3066     }
3067   return NULL_RTX;
3068 }
3069 
3070 
3071 enum reg_class
3072 xtensa_preferred_reload_class (rtx x, enum reg_class rclass, int isoutput)
3073 {
3074   if (!isoutput && CONSTANT_P (x) && GET_CODE (x) == CONST_DOUBLE)
3075     return NO_REGS;
3076 
3077   /* Don't use the stack pointer or hard frame pointer for reloads!
3078      The hard frame pointer would normally be OK except that it may
3079      briefly hold an incoming argument in the prologue, and reload
3080      won't know that it is live because the hard frame pointer is
3081      treated specially.  */
3082 
3083   if (rclass == AR_REGS || rclass == GR_REGS)
3084     return RL_REGS;
3085 
3086   return rclass;
3087 }
3088 
3089 
3090 enum reg_class
3091 xtensa_secondary_reload (bool in_p, rtx x, enum reg_class rclass,
3092 			 enum machine_mode mode, secondary_reload_info *sri)
3093 {
3094   int regno;
3095 
3096   if (in_p && constantpool_mem_p (x))
3097     {
3098       if (rclass == FP_REGS)
3099 	return RL_REGS;
3100 
3101       if (mode == QImode)
3102 	sri->icode = CODE_FOR_reloadqi_literal;
3103       else if (mode == HImode)
3104 	sri->icode = CODE_FOR_reloadhi_literal;
3105     }
3106 
3107   regno = xt_true_regnum (x);
3108   if (ACC_REG_P (regno))
3109     return ((rclass == GR_REGS || rclass == RL_REGS) ? NO_REGS : RL_REGS);
3110   if (rclass == ACC_REG)
3111     return (GP_REG_P (regno) ? NO_REGS : RL_REGS);
3112 
3113   return NO_REGS;
3114 }
3115 
3116 
3117 void
3118 order_regs_for_local_alloc (void)
3119 {
3120   if (!leaf_function_p ())
3121     {
3122       memcpy (reg_alloc_order, reg_nonleaf_alloc_order,
3123 	      FIRST_PSEUDO_REGISTER * sizeof (int));
3124     }
3125   else
3126     {
3127       int i, num_arg_regs;
3128       int nxt = 0;
3129 
3130       /* Use the AR registers in increasing order (skipping a0 and a1)
3131 	 but save the incoming argument registers for a last resort.  */
3132       num_arg_regs = crtl->args.info.arg_words;
3133       if (num_arg_regs > MAX_ARGS_IN_REGISTERS)
3134 	num_arg_regs = MAX_ARGS_IN_REGISTERS;
3135       for (i = GP_ARG_FIRST; i < 16 - num_arg_regs; i++)
3136 	reg_alloc_order[nxt++] = i + num_arg_regs;
3137       for (i = 0; i < num_arg_regs; i++)
3138 	reg_alloc_order[nxt++] = GP_ARG_FIRST + i;
3139 
3140       /* List the coprocessor registers in order.  */
3141       for (i = 0; i < BR_REG_NUM; i++)
3142 	reg_alloc_order[nxt++] = BR_REG_FIRST + i;
3143 
3144       /* List the FP registers in order for now.  */
3145       for (i = 0; i < 16; i++)
3146 	reg_alloc_order[nxt++] = FP_REG_FIRST + i;
3147 
3148       /* GCC requires that we list *all* the registers....  */
3149       reg_alloc_order[nxt++] = 0;	/* a0 = return address */
3150       reg_alloc_order[nxt++] = 1;	/* a1 = stack pointer */
3151       reg_alloc_order[nxt++] = 16;	/* pseudo frame pointer */
3152       reg_alloc_order[nxt++] = 17;	/* pseudo arg pointer */
3153 
3154       reg_alloc_order[nxt++] = ACC_REG_FIRST;	/* MAC16 accumulator */
3155     }
3156 }
3157 
3158 
3159 /* Some Xtensa targets support multiple bss sections.  If the section
3160    name ends with ".bss", add SECTION_BSS to the flags.  */
3161 
3162 static unsigned int
3163 xtensa_multibss_section_type_flags (tree decl, const char *name, int reloc)
3164 {
3165   unsigned int flags = default_section_type_flags (decl, name, reloc);
3166   const char *suffix;
3167 
3168   suffix = strrchr (name, '.');
3169   if (suffix && strcmp (suffix, ".bss") == 0)
3170     {
3171       if (!decl || (TREE_CODE (decl) == VAR_DECL
3172 		    && DECL_INITIAL (decl) == NULL_TREE))
3173 	flags |= SECTION_BSS;  /* @nobits */
3174       else
3175 	warning (0, "only uninitialized variables can be placed in a "
3176 		 ".bss section");
3177     }
3178 
3179   return flags;
3180 }
3181 
3182 
3183 /* The literal pool stays with the function.  */
3184 
3185 static section *
3186 xtensa_select_rtx_section (enum machine_mode mode ATTRIBUTE_UNUSED,
3187 			   rtx x ATTRIBUTE_UNUSED,
3188 			   unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
3189 {
3190   return function_section (current_function_decl);
3191 }
3192 
3193 
3194 /* Compute a (partial) cost for rtx X.  Return true if the complete
3195    cost has been computed, and false if subexpressions should be
3196    scanned.  In either case, *TOTAL contains the cost result.  */
3197 
3198 static bool
3199 xtensa_rtx_costs (rtx x, int code, int outer_code, int *total,
3200 		  bool speed ATTRIBUTE_UNUSED)
3201 {
3202   switch (code)
3203     {
3204     case CONST_INT:
3205       switch (outer_code)
3206 	{
3207 	case SET:
3208 	  if (xtensa_simm12b (INTVAL (x)))
3209 	    {
3210 	      *total = 4;
3211 	      return true;
3212 	    }
3213 	  break;
3214 	case PLUS:
3215 	  if (xtensa_simm8 (INTVAL (x))
3216 	      || xtensa_simm8x256 (INTVAL (x)))
3217 	    {
3218 	      *total = 0;
3219 	      return true;
3220 	    }
3221 	  break;
3222 	case AND:
3223 	  if (xtensa_mask_immediate (INTVAL (x)))
3224 	    {
3225 	      *total = 0;
3226 	      return true;
3227 	    }
3228 	  break;
3229 	case COMPARE:
3230 	  if ((INTVAL (x) == 0) || xtensa_b4const (INTVAL (x)))
3231 	    {
3232 	      *total = 0;
3233 	      return true;
3234 	    }
3235 	  break;
3236 	case ASHIFT:
3237 	case ASHIFTRT:
3238 	case LSHIFTRT:
3239 	case ROTATE:
3240 	case ROTATERT:
3241 	  /* No way to tell if X is the 2nd operand so be conservative.  */
3242 	default: break;
3243 	}
3244       if (xtensa_simm12b (INTVAL (x)))
3245 	*total = 5;
3246       else if (TARGET_CONST16)
3247 	*total = COSTS_N_INSNS (2);
3248       else
3249 	*total = 6;
3250       return true;
3251 
3252     case CONST:
3253     case LABEL_REF:
3254     case SYMBOL_REF:
3255       if (TARGET_CONST16)
3256 	*total = COSTS_N_INSNS (2);
3257       else
3258 	*total = 5;
3259       return true;
3260 
3261     case CONST_DOUBLE:
3262       if (TARGET_CONST16)
3263 	*total = COSTS_N_INSNS (4);
3264       else
3265 	*total = 7;
3266       return true;
3267 
3268     case MEM:
3269       {
3270 	int num_words =
3271 	  (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD) ?  2 : 1;
3272 
3273 	if (memory_address_p (GET_MODE (x), XEXP ((x), 0)))
3274 	  *total = COSTS_N_INSNS (num_words);
3275 	else
3276 	  *total = COSTS_N_INSNS (2*num_words);
3277 	return true;
3278       }
3279 
3280     case FFS:
3281     case CTZ:
3282       *total = COSTS_N_INSNS (TARGET_NSA ? 5 : 50);
3283       return true;
3284 
3285     case CLZ:
3286       *total = COSTS_N_INSNS (TARGET_NSA ? 1 : 50);
3287       return true;
3288 
3289     case NOT:
3290       *total = COSTS_N_INSNS ((GET_MODE (x) == DImode) ? 3 : 2);
3291       return true;
3292 
3293     case AND:
3294     case IOR:
3295     case XOR:
3296       if (GET_MODE (x) == DImode)
3297 	*total = COSTS_N_INSNS (2);
3298       else
3299 	*total = COSTS_N_INSNS (1);
3300       return true;
3301 
3302     case ASHIFT:
3303     case ASHIFTRT:
3304     case LSHIFTRT:
3305       if (GET_MODE (x) == DImode)
3306 	*total = COSTS_N_INSNS (50);
3307       else
3308 	*total = COSTS_N_INSNS (1);
3309       return true;
3310 
3311     case ABS:
3312       {
3313 	enum machine_mode xmode = GET_MODE (x);
3314 	if (xmode == SFmode)
3315 	  *total = COSTS_N_INSNS (TARGET_HARD_FLOAT ? 1 : 50);
3316 	else if (xmode == DFmode)
3317 	  *total = COSTS_N_INSNS (50);
3318 	else
3319 	  *total = COSTS_N_INSNS (4);
3320 	return true;
3321       }
3322 
3323     case PLUS:
3324     case MINUS:
3325       {
3326 	enum machine_mode xmode = GET_MODE (x);
3327 	if (xmode == SFmode)
3328 	  *total = COSTS_N_INSNS (TARGET_HARD_FLOAT ? 1 : 50);
3329 	else if (xmode == DFmode || xmode == DImode)
3330 	  *total = COSTS_N_INSNS (50);
3331 	else
3332 	  *total = COSTS_N_INSNS (1);
3333 	return true;
3334       }
3335 
3336     case NEG:
3337       *total = COSTS_N_INSNS ((GET_MODE (x) == DImode) ? 4 : 2);
3338       return true;
3339 
3340     case MULT:
3341       {
3342 	enum machine_mode xmode = GET_MODE (x);
3343 	if (xmode == SFmode)
3344 	  *total = COSTS_N_INSNS (TARGET_HARD_FLOAT ? 4 : 50);
3345 	else if (xmode == DFmode)
3346 	  *total = COSTS_N_INSNS (50);
3347 	else if (xmode == DImode)
3348 	  *total = COSTS_N_INSNS (TARGET_MUL32_HIGH ? 10 : 50);
3349 	else if (TARGET_MUL32)
3350 	  *total = COSTS_N_INSNS (4);
3351 	else if (TARGET_MAC16)
3352 	  *total = COSTS_N_INSNS (16);
3353 	else if (TARGET_MUL16)
3354 	  *total = COSTS_N_INSNS (12);
3355 	else
3356 	  *total = COSTS_N_INSNS (50);
3357 	return true;
3358       }
3359 
3360     case DIV:
3361     case MOD:
3362       {
3363 	enum machine_mode xmode = GET_MODE (x);
3364 	if (xmode == SFmode)
3365 	  {
3366 	    *total = COSTS_N_INSNS (TARGET_HARD_FLOAT_DIV ? 8 : 50);
3367 	    return true;
3368 	  }
3369 	else if (xmode == DFmode)
3370 	  {
3371 	    *total = COSTS_N_INSNS (50);
3372 	    return true;
3373 	  }
3374       }
3375       /* Fall through.  */
3376 
3377     case UDIV:
3378     case UMOD:
3379       {
3380 	enum machine_mode xmode = GET_MODE (x);
3381 	if (xmode == DImode)
3382 	  *total = COSTS_N_INSNS (50);
3383 	else if (TARGET_DIV32)
3384 	  *total = COSTS_N_INSNS (32);
3385 	else
3386 	  *total = COSTS_N_INSNS (50);
3387 	return true;
3388       }
3389 
3390     case SQRT:
3391       if (GET_MODE (x) == SFmode)
3392 	*total = COSTS_N_INSNS (TARGET_HARD_FLOAT_SQRT ? 8 : 50);
3393       else
3394 	*total = COSTS_N_INSNS (50);
3395       return true;
3396 
3397     case SMIN:
3398     case UMIN:
3399     case SMAX:
3400     case UMAX:
3401       *total = COSTS_N_INSNS (TARGET_MINMAX ? 1 : 50);
3402       return true;
3403 
3404     case SIGN_EXTRACT:
3405     case SIGN_EXTEND:
3406       *total = COSTS_N_INSNS (TARGET_SEXT ? 1 : 2);
3407       return true;
3408 
3409     case ZERO_EXTRACT:
3410     case ZERO_EXTEND:
3411       *total = COSTS_N_INSNS (1);
3412       return true;
3413 
3414     default:
3415       return false;
3416     }
3417 }
3418 
3419 /* Worker function for TARGET_RETURN_IN_MEMORY.  */
3420 
3421 static bool
3422 xtensa_return_in_memory (const_tree type, const_tree fntype ATTRIBUTE_UNUSED)
3423 {
3424   return ((unsigned HOST_WIDE_INT) int_size_in_bytes (type)
3425 	  > 4 * UNITS_PER_WORD);
3426 }
3427 
3428 /* Worker function for TARGET_FUNCTION_VALUE.  */
3429 
3430 rtx
3431 xtensa_function_value (const_tree valtype, const_tree func ATTRIBUTE_UNUSED,
3432                       bool outgoing)
3433 {
3434   return gen_rtx_REG ((INTEGRAL_TYPE_P (valtype)
3435                       && TYPE_PRECISION (valtype) < BITS_PER_WORD)
3436                      ? SImode : TYPE_MODE (valtype),
3437                      outgoing ? GP_OUTGOING_RETURN : GP_RETURN);
3438 }
3439 
3440 /* The static chain is passed in memory.  Provide rtx giving 'mem'
3441    expressions that denote where they are stored.  */
3442 
3443 static rtx
3444 xtensa_static_chain (const_tree ARG_UNUSED (fndecl), bool incoming_p)
3445 {
3446   rtx base = incoming_p ? arg_pointer_rtx : stack_pointer_rtx;
3447   return gen_frame_mem (Pmode, plus_constant (base, -5 * UNITS_PER_WORD));
3448 }
3449 
3450 
3451 /* TRAMPOLINE_TEMPLATE: For Xtensa, the trampoline must perform an ENTRY
3452    instruction with a minimal stack frame in order to get some free
3453    registers.  Once the actual call target is known, the proper stack frame
3454    size is extracted from the ENTRY instruction at the target and the
3455    current frame is adjusted to match.  The trampoline then transfers
3456    control to the instruction following the ENTRY at the target.  Note:
3457    this assumes that the target begins with an ENTRY instruction.  */
3458 
3459 static void
3460 xtensa_asm_trampoline_template (FILE *stream)
3461 {
3462   bool use_call0 = (TARGET_CONST16 || TARGET_ABSOLUTE_LITERALS);
3463 
3464   fprintf (stream, "\t.begin no-transform\n");
3465   fprintf (stream, "\tentry\tsp, %d\n", MIN_FRAME_SIZE);
3466 
3467   if (use_call0)
3468     {
3469       /* Save the return address.  */
3470       fprintf (stream, "\tmov\ta10, a0\n");
3471 
3472       /* Use a CALL0 instruction to skip past the constants and in the
3473 	 process get the PC into A0.  This allows PC-relative access to
3474 	 the constants without relying on L32R.  */
3475       fprintf (stream, "\tcall0\t.Lskipconsts\n");
3476     }
3477   else
3478     fprintf (stream, "\tj\t.Lskipconsts\n");
3479 
3480   fprintf (stream, "\t.align\t4\n");
3481   fprintf (stream, ".Lchainval:%s0\n", integer_asm_op (4, TRUE));
3482   fprintf (stream, ".Lfnaddr:%s0\n", integer_asm_op (4, TRUE));
3483   fprintf (stream, ".Lskipconsts:\n");
3484 
3485   /* Load the static chain and function address from the trampoline.  */
3486   if (use_call0)
3487     {
3488       fprintf (stream, "\taddi\ta0, a0, 3\n");
3489       fprintf (stream, "\tl32i\ta9, a0, 0\n");
3490       fprintf (stream, "\tl32i\ta8, a0, 4\n");
3491     }
3492   else
3493     {
3494       fprintf (stream, "\tl32r\ta9, .Lchainval\n");
3495       fprintf (stream, "\tl32r\ta8, .Lfnaddr\n");
3496     }
3497 
3498   /* Store the static chain.  */
3499   fprintf (stream, "\ts32i\ta9, sp, %d\n", MIN_FRAME_SIZE - 20);
3500 
3501   /* Set the proper stack pointer value.  */
3502   fprintf (stream, "\tl32i\ta9, a8, 0\n");
3503   fprintf (stream, "\textui\ta9, a9, %d, 12\n",
3504 	   TARGET_BIG_ENDIAN ? 8 : 12);
3505   fprintf (stream, "\tslli\ta9, a9, 3\n");
3506   fprintf (stream, "\taddi\ta9, a9, %d\n", -MIN_FRAME_SIZE);
3507   fprintf (stream, "\tsub\ta9, sp, a9\n");
3508   fprintf (stream, "\tmovsp\tsp, a9\n");
3509 
3510   if (use_call0)
3511     /* Restore the return address.  */
3512     fprintf (stream, "\tmov\ta0, a10\n");
3513 
3514   /* Jump to the instruction following the ENTRY.  */
3515   fprintf (stream, "\taddi\ta8, a8, 3\n");
3516   fprintf (stream, "\tjx\ta8\n");
3517 
3518   /* Pad size to a multiple of TRAMPOLINE_ALIGNMENT.  */
3519   if (use_call0)
3520     fprintf (stream, "\t.byte\t0\n");
3521   else
3522     fprintf (stream, "\tnop\n");
3523 
3524   fprintf (stream, "\t.end no-transform\n");
3525 }
3526 
3527 static void
3528 xtensa_trampoline_init (rtx m_tramp, tree fndecl, rtx chain)
3529 {
3530   rtx func = XEXP (DECL_RTL (fndecl), 0);
3531   bool use_call0 = (TARGET_CONST16 || TARGET_ABSOLUTE_LITERALS);
3532   int chain_off = use_call0 ? 12 : 8;
3533   int func_off = use_call0 ? 16 : 12;
3534 
3535   emit_block_move (m_tramp, assemble_trampoline_template (),
3536 		   GEN_INT (TRAMPOLINE_SIZE), BLOCK_OP_NORMAL);
3537 
3538   emit_move_insn (adjust_address (m_tramp, SImode, chain_off), chain);
3539   emit_move_insn (adjust_address (m_tramp, SImode, func_off), func);
3540   emit_library_call (gen_rtx_SYMBOL_REF (Pmode, "__xtensa_sync_caches"),
3541 		     0, VOIDmode, 1, XEXP (m_tramp, 0), Pmode);
3542 }
3543 
3544 
3545 #include "gt-xtensa.h"
3546