xref: /netbsd-src/external/gpl3/gcc.old/dist/gcc/config/riscv/riscv.h (revision 9fd8799cb5ceb66c69f2eb1a6d26a1d587ba1f1e)
1 /* Definition of RISC-V target for GNU compiler.
2    Copyright (C) 2011-2018 Free Software Foundation, Inc.
3    Contributed by Andrew Waterman (andrew@sifive.com).
4    Based on MIPS target for GNU compiler.
5 
6 This file is part of GCC.
7 
8 GCC is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3, or (at your option)
11 any later version.
12 
13 GCC is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16 GNU General Public License 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 #ifndef GCC_RISCV_H
23 #define GCC_RISCV_H
24 
25 #include "config/riscv/riscv-opts.h"
26 
27 /* Target CPU builtins.  */
28 #define TARGET_CPU_CPP_BUILTINS() riscv_cpu_cpp_builtins (pfile)
29 
30 /* Default target_flags if no switches are specified  */
31 
32 #ifndef TARGET_DEFAULT
33 #define TARGET_DEFAULT 0
34 #endif
35 
36 #ifndef RISCV_TUNE_STRING_DEFAULT
37 #define RISCV_TUNE_STRING_DEFAULT "rocket"
38 #endif
39 
40 /* Support for a compile-time default CPU, et cetera.  The rules are:
41    --with-arch is ignored if -march is specified.
42    --with-abi is ignored if -mabi is specified.
43    --with-tune is ignored if -mtune is specified.  */
44 #define OPTION_DEFAULT_SPECS \
45   {"tune", "%{!mtune=*:-mtune=%(VALUE)}" }, \
46   {"arch", "%{!march=*:-march=%(VALUE)}" }, \
47   {"abi", "%{!mabi=*:-mabi=%(VALUE)}" }, \
48 
49 #ifdef IN_LIBGCC2
50 #undef TARGET_64BIT
51 /* Make this compile time constant for libgcc2 */
52 #define TARGET_64BIT           (__riscv_xlen == 64)
53 #endif /* IN_LIBGCC2 */
54 
55 #undef ASM_SPEC
56 #define ASM_SPEC "\
57 %(subtarget_asm_debugging_spec) \
58 %{" FPIE_OR_FPIC_SPEC ":-fpic} \
59 %{march=*} \
60 %{mabi=*} \
61 %(subtarget_asm_spec)"
62 
63 #define TARGET_DEFAULT_CMODEL CM_MEDLOW
64 
65 #define LOCAL_LABEL_PREFIX	"."
66 #define USER_LABEL_PREFIX	""
67 
68 /* Offsets recorded in opcodes are a multiple of this alignment factor.
69    The default for this in 64-bit mode is 8, which causes problems with
70    SFmode register saves.  */
71 #define DWARF_CIE_DATA_ALIGNMENT -4
72 
73 /* The mapping from gcc register number to DWARF 2 CFA column number.  */
74 #define DWARF_FRAME_REGNUM(REGNO) \
75   (GP_REG_P (REGNO) || FP_REG_P (REGNO) ? REGNO : INVALID_REGNUM)
76 
77 /* The DWARF 2 CFA column which tracks the return address.  */
78 #define DWARF_FRAME_RETURN_COLUMN RETURN_ADDR_REGNUM
79 #define INCOMING_RETURN_ADDR_RTX gen_rtx_REG (VOIDmode, RETURN_ADDR_REGNUM)
80 
81 /* Describe how we implement __builtin_eh_return.  */
82 #define EH_RETURN_DATA_REGNO(N) \
83   ((N) < 4 ? (N) + GP_ARG_FIRST : INVALID_REGNUM)
84 
85 #define EH_RETURN_STACKADJ_RTX  gen_rtx_REG (Pmode, GP_ARG_FIRST + 4)
86 
87 /* Target machine storage layout */
88 
89 #define BITS_BIG_ENDIAN 0
90 #define BYTES_BIG_ENDIAN 0
91 #define WORDS_BIG_ENDIAN 0
92 
93 #define MAX_BITS_PER_WORD 64
94 
95 /* Width of a word, in units (bytes).  */
96 #define UNITS_PER_WORD (TARGET_64BIT ? 8 : 4)
97 #ifndef IN_LIBGCC2
98 #define MIN_UNITS_PER_WORD 4
99 #endif
100 
101 /* The `Q' extension is not yet supported.  */
102 #define UNITS_PER_FP_REG (TARGET_DOUBLE_FLOAT ? 8 : 4)
103 
104 /* The largest type that can be passed in floating-point registers.  */
105 #define UNITS_PER_FP_ARG					\
106   (riscv_abi == ABI_ILP32 || riscv_abi == ABI_LP64 ? 0 :	\
107    riscv_abi == ABI_ILP32F || riscv_abi == ABI_LP64F ? 4 : 8)	\
108 
109 /* Set the sizes of the core types.  */
110 #define SHORT_TYPE_SIZE 16
111 #define INT_TYPE_SIZE 32
112 #define LONG_LONG_TYPE_SIZE 64
113 #define POINTER_SIZE (riscv_abi >= ABI_LP64 ? 64 : 32)
114 #define LONG_TYPE_SIZE POINTER_SIZE
115 
116 #define FLOAT_TYPE_SIZE 32
117 #define DOUBLE_TYPE_SIZE 64
118 #define LONG_DOUBLE_TYPE_SIZE 128
119 
120 /* Allocation boundary (in *bits*) for storing arguments in argument list.  */
121 #define PARM_BOUNDARY BITS_PER_WORD
122 
123 /* Allocation boundary (in *bits*) for the code of a function.  */
124 #define FUNCTION_BOUNDARY (TARGET_RVC ? 16 : 32)
125 
126 /* The smallest supported stack boundary the calling convention supports.  */
127 #define STACK_BOUNDARY (2 * BITS_PER_WORD)
128 
129 /* The ABI stack alignment.  */
130 #define ABI_STACK_BOUNDARY 128
131 
132 /* There is no point aligning anything to a rounder boundary than this.  */
133 #define BIGGEST_ALIGNMENT 128
134 
135 /* The user-level ISA permits unaligned accesses, but they are not required
136    of the privileged architecture.  */
137 #define STRICT_ALIGNMENT TARGET_STRICT_ALIGN
138 
139 /* Define this if you wish to imitate the way many other C compilers
140    handle alignment of bitfields and the structures that contain
141    them.
142 
143    The behavior is that the type written for a bit-field (`int',
144    `short', or other integer type) imposes an alignment for the
145    entire structure, as if the structure really did contain an
146    ordinary field of that type.  In addition, the bit-field is placed
147    within the structure so that it would fit within such a field,
148    not crossing a boundary for it.
149 
150    Thus, on most machines, a bit-field whose type is written as `int'
151    would not cross a four-byte boundary, and would force four-byte
152    alignment for the whole structure.  (The alignment used may not
153    be four bytes; it is controlled by the other alignment
154    parameters.)
155 
156    If the macro is defined, its definition should be a C expression;
157    a nonzero value for the expression enables this behavior.  */
158 
159 #define PCC_BITFIELD_TYPE_MATTERS 1
160 
161 /* An integer expression for the size in bits of the largest integer machine
162    mode that should actually be used.  We allow pairs of registers.  */
163 #define MAX_FIXED_MODE_SIZE GET_MODE_BITSIZE (TARGET_64BIT ? TImode : DImode)
164 
165 /* If defined, a C expression to compute the alignment for a static
166    variable.  TYPE is the data type, and ALIGN is the alignment that
167    the object would ordinarily have.  The value of this macro is used
168    instead of that alignment to align the object.
169 
170    If this macro is not defined, then ALIGN is used.
171 
172    One use of this macro is to increase alignment of medium-size
173    data to make it all fit in fewer cache lines.  Another is to
174    cause character arrays to be word-aligned so that `strcpy' calls
175    that copy constants to character arrays can be done inline.  */
176 
177 #define DATA_ALIGNMENT(TYPE, ALIGN)					\
178   ((((ALIGN) < BITS_PER_WORD)						\
179     && (TREE_CODE (TYPE) == ARRAY_TYPE					\
180 	|| TREE_CODE (TYPE) == UNION_TYPE				\
181 	|| TREE_CODE (TYPE) == RECORD_TYPE)) ? BITS_PER_WORD : (ALIGN))
182 
183 /* We need this for the same reason as DATA_ALIGNMENT, namely to cause
184    character arrays to be word-aligned so that `strcpy' calls that copy
185    constants to character arrays can be done inline, and 'strcmp' can be
186    optimised to use word loads. */
187 #define LOCAL_ALIGNMENT(TYPE, ALIGN) \
188   DATA_ALIGNMENT (TYPE, ALIGN)
189 
190 /* Define if operations between registers always perform the operation
191    on the full register even if a narrower mode is specified.  */
192 #define WORD_REGISTER_OPERATIONS 1
193 
194 /* When in 64-bit mode, move insns will sign extend SImode and CCmode
195    moves.  All other references are zero extended.  */
196 #define LOAD_EXTEND_OP(MODE) \
197   (TARGET_64BIT && (MODE) == SImode ? SIGN_EXTEND : ZERO_EXTEND)
198 
199 /* Define this macro if it is advisable to hold scalars in registers
200    in a wider mode than that declared by the program.  In such cases,
201    the value is constrained to be within the bounds of the declared
202    type, but kept valid in the wider mode.  The signedness of the
203    extension may differ from that of the type.  */
204 
205 #define PROMOTE_MODE(MODE, UNSIGNEDP, TYPE)	\
206   if (GET_MODE_CLASS (MODE) == MODE_INT		\
207       && GET_MODE_SIZE (MODE) < UNITS_PER_WORD)	\
208     {						\
209       if ((MODE) == SImode)			\
210 	(UNSIGNEDP) = 0;			\
211       (MODE) = word_mode;			\
212     }
213 
214 /* Pmode is always the same as ptr_mode, but not always the same as word_mode.
215    Extensions of pointers to word_mode must be signed.  */
216 #define POINTERS_EXTEND_UNSIGNED false
217 
218 /* Define if loading short immediate values into registers sign extends.  */
219 #define SHORT_IMMEDIATES_SIGN_EXTEND 1
220 
221 /* Standard register usage.  */
222 
223 /* Number of hardware registers.  We have:
224 
225    - 32 integer registers
226    - 32 floating point registers
227    - 2 fake registers:
228 	- ARG_POINTER_REGNUM
229 	- FRAME_POINTER_REGNUM */
230 
231 #define FIRST_PSEUDO_REGISTER 66
232 
233 /* x0, sp, gp, and tp are fixed.  */
234 
235 #define FIXED_REGISTERS							\
236 { /* General registers.  */						\
237   1, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,			\
238   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,			\
239   /* Floating-point registers.  */					\
240   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,			\
241   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,			\
242   /* Others.  */							\
243   1, 1									\
244 }
245 
246 /* a0-a7, t0-t6, fa0-fa7, and ft0-ft11 are volatile across calls.
247    The call RTLs themselves clobber ra.  */
248 
249 #define CALL_USED_REGISTERS						\
250 { /* General registers.  */						\
251   1, 0, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1,			\
252   1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1,			\
253   /* Floating-point registers.  */					\
254   1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1,			\
255   1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1,			\
256   /* Others.  */							\
257   1, 1									\
258 }
259 
260 /* Internal macros to classify an ISA register's type.  */
261 
262 #define GP_REG_FIRST 0
263 #define GP_REG_LAST  31
264 #define GP_REG_NUM   (GP_REG_LAST - GP_REG_FIRST + 1)
265 
266 #define FP_REG_FIRST 32
267 #define FP_REG_LAST  63
268 #define FP_REG_NUM   (FP_REG_LAST - FP_REG_FIRST + 1)
269 
270 /* The DWARF 2 CFA column which tracks the return address from a
271    signal handler context.  This means that to maintain backwards
272    compatibility, no hard register can be assigned this column if it
273    would need to be handled by the DWARF unwinder.  */
274 #define DWARF_ALT_FRAME_RETURN_COLUMN 64
275 
276 #define GP_REG_P(REGNO)	\
277   ((unsigned int) ((int) (REGNO) - GP_REG_FIRST) < GP_REG_NUM)
278 #define FP_REG_P(REGNO)  \
279   ((unsigned int) ((int) (REGNO) - FP_REG_FIRST) < FP_REG_NUM)
280 
281 #define FP_REG_RTX_P(X) (REG_P (X) && FP_REG_P (REGNO (X)))
282 
283 /* Use s0 as the frame pointer if it is so requested.  */
284 #define HARD_FRAME_POINTER_REGNUM 8
285 #define STACK_POINTER_REGNUM 2
286 #define THREAD_POINTER_REGNUM 4
287 
288 /* These two registers don't really exist: they get eliminated to either
289    the stack or hard frame pointer.  */
290 #define ARG_POINTER_REGNUM 64
291 #define FRAME_POINTER_REGNUM 65
292 
293 /* Register in which static-chain is passed to a function.  */
294 #define STATIC_CHAIN_REGNUM (GP_TEMP_FIRST + 2)
295 
296 /* Registers used as temporaries in prologue/epilogue code.
297 
298    The prologue registers mustn't conflict with any
299    incoming arguments, the static chain pointer, or the frame pointer.
300    The epilogue temporary mustn't conflict with the return registers,
301    the frame pointer, the EH stack adjustment, or the EH data registers. */
302 
303 #define RISCV_PROLOGUE_TEMP_REGNUM (GP_TEMP_FIRST + 1)
304 #define RISCV_PROLOGUE_TEMP(MODE) gen_rtx_REG (MODE, RISCV_PROLOGUE_TEMP_REGNUM)
305 
306 #define MCOUNT_NAME "_mcount"
307 
308 #define NO_PROFILE_COUNTERS 1
309 
310 /* Emit rtl for profiling.  Output assembler code to FILE
311    to call "_mcount" for profiling a function entry.  */
312 #define PROFILE_HOOK(LABEL)						\
313   {									\
314     rtx fun, ra;							\
315     ra = get_hard_reg_initial_val (Pmode, RETURN_ADDR_REGNUM);		\
316     fun = gen_rtx_SYMBOL_REF (Pmode, MCOUNT_NAME);			\
317     emit_library_call (fun, LCT_NORMAL, VOIDmode, ra, Pmode);		\
318   }
319 
320 /* All the work done in PROFILE_HOOK, but still required.  */
321 #define FUNCTION_PROFILER(STREAM, LABELNO) do { } while (0)
322 
323 /* Define this macro if it is as good or better to call a constant
324    function address than to call an address kept in a register.  */
325 #define NO_FUNCTION_CSE 1
326 
327 /* Define the classes of registers for register constraints in the
328    machine description.  Also define ranges of constants.
329 
330    One of the classes must always be named ALL_REGS and include all hard regs.
331    If there is more than one class, another class must be named NO_REGS
332    and contain no registers.
333 
334    The name GENERAL_REGS must be the name of a class (or an alias for
335    another name such as ALL_REGS).  This is the class of registers
336    that is allowed by "g" or "r" in a register constraint.
337    Also, registers outside this class are allocated only when
338    instructions express preferences for them.
339 
340    The classes must be numbered in nondecreasing order; that is,
341    a larger-numbered class must never be contained completely
342    in a smaller-numbered class.
343 
344    For any two classes, it is very desirable that there be another
345    class that represents their union.  */
346 
347 enum reg_class
348 {
349   NO_REGS,			/* no registers in set */
350   SIBCALL_REGS,			/* registers used by indirect sibcalls */
351   JALR_REGS,			/* registers used by indirect calls */
352   GR_REGS,			/* integer registers */
353   FP_REGS,			/* floating-point registers */
354   FRAME_REGS,			/* arg pointer and frame pointer */
355   ALL_REGS,			/* all registers */
356   LIM_REG_CLASSES		/* max value + 1 */
357 };
358 
359 #define N_REG_CLASSES (int) LIM_REG_CLASSES
360 
361 #define GENERAL_REGS GR_REGS
362 
363 /* An initializer containing the names of the register classes as C
364    string constants.  These names are used in writing some of the
365    debugging dumps.  */
366 
367 #define REG_CLASS_NAMES							\
368 {									\
369   "NO_REGS",								\
370   "SIBCALL_REGS",							\
371   "JALR_REGS",								\
372   "GR_REGS",								\
373   "FP_REGS",								\
374   "FRAME_REGS",								\
375   "ALL_REGS"								\
376 }
377 
378 /* An initializer containing the contents of the register classes,
379    as integers which are bit masks.  The Nth integer specifies the
380    contents of class N.  The way the integer MASK is interpreted is
381    that register R is in the class if `MASK & (1 << R)' is 1.
382 
383    When the machine has more than 32 registers, an integer does not
384    suffice.  Then the integers are replaced by sub-initializers,
385    braced groupings containing several integers.  Each
386    sub-initializer must be suitable as an initializer for the type
387    `HARD_REG_SET' which is defined in `hard-reg-set.h'.  */
388 
389 #define REG_CLASS_CONTENTS						\
390 {									\
391   { 0x00000000, 0x00000000, 0x00000000 },	/* NO_REGS */		\
392   { 0xf00000c0, 0x00000000, 0x00000000 },	/* SIBCALL_REGS */	\
393   { 0xffffffc0, 0x00000000, 0x00000000 },	/* JALR_REGS */		\
394   { 0xffffffff, 0x00000000, 0x00000000 },	/* GR_REGS */		\
395   { 0x00000000, 0xffffffff, 0x00000000 },	/* FP_REGS */		\
396   { 0x00000000, 0x00000000, 0x00000003 },	/* FRAME_REGS */	\
397   { 0xffffffff, 0xffffffff, 0x00000003 }	/* ALL_REGS */		\
398 }
399 
400 /* A C expression whose value is a register class containing hard
401    register REGNO.  In general there is more that one such class;
402    choose a class which is "minimal", meaning that no smaller class
403    also contains the register.  */
404 
405 #define REGNO_REG_CLASS(REGNO) riscv_regno_to_class[ (REGNO) ]
406 
407 /* A macro whose definition is the name of the class to which a
408    valid base register must belong.  A base register is one used in
409    an address which is the register value plus a displacement.  */
410 
411 #define BASE_REG_CLASS GR_REGS
412 
413 /* A macro whose definition is the name of the class to which a
414    valid index register must belong.  An index register is one used
415    in an address where its value is either multiplied by a scale
416    factor or added to another register (as well as added to a
417    displacement).  */
418 
419 #define INDEX_REG_CLASS NO_REGS
420 
421 /* We generally want to put call-clobbered registers ahead of
422    call-saved ones.  (IRA expects this.)  */
423 
424 #define REG_ALLOC_ORDER							\
425 { \
426   /* Call-clobbered GPRs.  */						\
427   15, 14, 13, 12, 11, 10, 16, 17, 6, 28, 29, 30, 31, 5, 7, 1,		\
428   /* Call-saved GPRs.  */						\
429   8, 9, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27,	       			\
430   /* GPRs that can never be exposed to the register allocator.  */	\
431   0, 2, 3, 4,								\
432   /* Call-clobbered FPRs.  */						\
433   47, 46, 45, 44, 43, 42, 32, 33, 34, 35, 36, 37, 38, 39, 48, 49,	\
434   60, 61, 62, 63,							\
435   /* Call-saved FPRs.  */						\
436   40, 41, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59,			\
437   /* None of the remaining classes have defined call-saved		\
438      registers.  */							\
439   64, 65								\
440 }
441 
442 /* True if VALUE is a signed 12-bit number.  */
443 
444 #define SMALL_OPERAND(VALUE) \
445   ((unsigned HOST_WIDE_INT) (VALUE) + IMM_REACH/2 < IMM_REACH)
446 
447 /* True if VALUE can be loaded into a register using LUI.  */
448 
449 #define LUI_OPERAND(VALUE)						\
450   (((VALUE) | ((1UL<<31) - IMM_REACH)) == ((1UL<<31) - IMM_REACH)	\
451    || ((VALUE) | ((1UL<<31) - IMM_REACH)) + IMM_REACH == 0)
452 
453 /* Stack layout; function entry, exit and calling.  */
454 
455 #define STACK_GROWS_DOWNWARD 1
456 
457 #define FRAME_GROWS_DOWNWARD 1
458 
459 #define RETURN_ADDR_RTX riscv_return_addr
460 
461 #define ELIMINABLE_REGS							\
462 {{ ARG_POINTER_REGNUM,   STACK_POINTER_REGNUM},				\
463  { ARG_POINTER_REGNUM,   HARD_FRAME_POINTER_REGNUM},			\
464  { FRAME_POINTER_REGNUM, STACK_POINTER_REGNUM},				\
465  { FRAME_POINTER_REGNUM, HARD_FRAME_POINTER_REGNUM}}				\
466 
467 #define INITIAL_ELIMINATION_OFFSET(FROM, TO, OFFSET) \
468   (OFFSET) = riscv_initial_elimination_offset (FROM, TO)
469 
470 /* Allocate stack space for arguments at the beginning of each function.  */
471 #define ACCUMULATE_OUTGOING_ARGS 1
472 
473 /* The argument pointer always points to the first argument.  */
474 #define FIRST_PARM_OFFSET(FNDECL) 0
475 
476 #define REG_PARM_STACK_SPACE(FNDECL) 0
477 
478 /* Define this if it is the responsibility of the caller to
479    allocate the area reserved for arguments passed in registers.
480    If `ACCUMULATE_OUTGOING_ARGS' is also defined, the only effect
481    of this macro is to determine whether the space is included in
482    `crtl->outgoing_args_size'.  */
483 #define OUTGOING_REG_PARM_STACK_SPACE(FNTYPE) 1
484 
485 #define PREFERRED_STACK_BOUNDARY riscv_stack_boundary
486 
487 /* Symbolic macros for the registers used to return integer and floating
488    point values.  */
489 
490 #define GP_RETURN GP_ARG_FIRST
491 #define FP_RETURN (UNITS_PER_FP_ARG == 0 ? GP_RETURN : FP_ARG_FIRST)
492 
493 #define MAX_ARGS_IN_REGISTERS 8
494 
495 /* Symbolic macros for the first/last argument registers.  */
496 
497 #define GP_ARG_FIRST (GP_REG_FIRST + 10)
498 #define GP_ARG_LAST  (GP_ARG_FIRST + MAX_ARGS_IN_REGISTERS - 1)
499 #define GP_TEMP_FIRST (GP_REG_FIRST + 5)
500 #define FP_ARG_FIRST (FP_REG_FIRST + 10)
501 #define FP_ARG_LAST  (FP_ARG_FIRST + MAX_ARGS_IN_REGISTERS - 1)
502 
503 #define CALLEE_SAVED_REG_NUMBER(REGNO)			\
504   ((REGNO) >= 8 && (REGNO) <= 9 ? (REGNO) - 8 :		\
505    (REGNO) >= 18 && (REGNO) <= 27 ? (REGNO) - 16 : -1)
506 
507 #define LIBCALL_VALUE(MODE) \
508   riscv_function_value (NULL_TREE, NULL_TREE, MODE)
509 
510 #define FUNCTION_VALUE(VALTYPE, FUNC) \
511   riscv_function_value (VALTYPE, FUNC, VOIDmode)
512 
513 #define FUNCTION_VALUE_REGNO_P(N) ((N) == GP_RETURN || (N) == FP_RETURN)
514 
515 /* 1 if N is a possible register number for function argument passing.
516    We have no FP argument registers when soft-float.  When FP registers
517    are 32 bits, we can't directly reference the odd numbered ones.  */
518 
519 /* Accept arguments in a0-a7, and in fa0-fa7 if permitted by the ABI.  */
520 #define FUNCTION_ARG_REGNO_P(N)						\
521   (IN_RANGE ((N), GP_ARG_FIRST, GP_ARG_LAST)				\
522    || (UNITS_PER_FP_ARG && IN_RANGE ((N), FP_ARG_FIRST, FP_ARG_LAST)))
523 
524 typedef struct {
525   /* Number of integer registers used so far, up to MAX_ARGS_IN_REGISTERS. */
526   unsigned int num_gprs;
527 
528   /* Number of floating-point registers used so far, likewise.  */
529   unsigned int num_fprs;
530 } CUMULATIVE_ARGS;
531 
532 /* Initialize a variable CUM of type CUMULATIVE_ARGS
533    for a call to a function whose data type is FNTYPE.
534    For a library call, FNTYPE is 0.  */
535 
536 #define INIT_CUMULATIVE_ARGS(CUM, FNTYPE, LIBNAME, INDIRECT, N_NAMED_ARGS) \
537   memset (&(CUM), 0, sizeof (CUM))
538 
539 #define EPILOGUE_USES(REGNO)	((REGNO) == RETURN_ADDR_REGNUM)
540 
541 /* Align based on stack boundary, which might have been set by the user.  */
542 #define RISCV_STACK_ALIGN(LOC) \
543   (((LOC) + ((PREFERRED_STACK_BOUNDARY/8)-1)) & -(PREFERRED_STACK_BOUNDARY/8))
544 
545 /* EXIT_IGNORE_STACK should be nonzero if, when returning from a function,
546    the stack pointer does not matter.  The value is tested only in
547    functions that have frame pointers.
548    No definition is equivalent to always zero.  */
549 
550 #define EXIT_IGNORE_STACK 1
551 
552 
553 /* Trampolines are a block of code followed by two pointers.  */
554 
555 #define TRAMPOLINE_CODE_SIZE 16
556 #define TRAMPOLINE_SIZE		\
557   ((Pmode == SImode)		\
558    ? TRAMPOLINE_CODE_SIZE	\
559    : (TRAMPOLINE_CODE_SIZE + POINTER_SIZE * 2))
560 #define TRAMPOLINE_ALIGNMENT POINTER_SIZE
561 
562 /* Addressing modes, and classification of registers for them.  */
563 
564 #define REGNO_OK_FOR_INDEX_P(REGNO) 0
565 #define REGNO_MODE_OK_FOR_BASE_P(REGNO, MODE) \
566   riscv_regno_mode_ok_for_base_p (REGNO, MODE, 1)
567 
568 /* The macros REG_OK_FOR..._P assume that the arg is a REG rtx
569    and check its validity for a certain class.
570    We have two alternate definitions for each of them.
571    The usual definition accepts all pseudo regs; the other rejects them all.
572    The symbol REG_OK_STRICT causes the latter definition to be used.
573 
574    Most source files want to accept pseudo regs in the hope that
575    they will get allocated to the class that the insn wants them to be in.
576    Some source files that are used after register allocation
577    need to be strict.  */
578 
579 #ifndef REG_OK_STRICT
580 #define REG_MODE_OK_FOR_BASE_P(X, MODE) \
581   riscv_regno_mode_ok_for_base_p (REGNO (X), MODE, 0)
582 #else
583 #define REG_MODE_OK_FOR_BASE_P(X, MODE) \
584   riscv_regno_mode_ok_for_base_p (REGNO (X), MODE, 1)
585 #endif
586 
587 #define REG_OK_FOR_INDEX_P(X) 0
588 
589 /* Maximum number of registers that can appear in a valid memory address.  */
590 
591 #define MAX_REGS_PER_ADDRESS 1
592 
593 #define CONSTANT_ADDRESS_P(X) \
594   (CONSTANT_P (X) && memory_address_p (SImode, X))
595 
596 /* This handles the magic '..CURRENT_FUNCTION' symbol, which means
597    'the start of the function that this code is output in'.  */
598 
599 #define ASM_OUTPUT_LABELREF(FILE,NAME)					\
600   do {									\
601     if (strcmp (NAME, "..CURRENT_FUNCTION") == 0)			\
602       asm_fprintf ((FILE), "%U%s",					\
603 		   XSTR (XEXP (DECL_RTL (current_function_decl),	\
604 			       0), 0));					\
605     else								\
606       asm_fprintf ((FILE), "%U%s", (NAME));				\
607   } while (0)
608 
609 #define JUMP_TABLES_IN_TEXT_SECTION 0
610 #define CASE_VECTOR_MODE SImode
611 #define CASE_VECTOR_PC_RELATIVE (riscv_cmodel != CM_MEDLOW)
612 
613 /* The load-address macro is used for PC-relative addressing of symbols
614    that bind locally.  Don't use it for symbols that should be addressed
615    via the GOT.  Also, avoid it for CM_MEDLOW, where LUI addressing
616    currently results in more opportunities for linker relaxation.  */
617 #define USE_LOAD_ADDRESS_MACRO(sym)					\
618   (!TARGET_EXPLICIT_RELOCS &&						\
619    ((flag_pic								\
620      && ((SYMBOL_REF_P (sym) && SYMBOL_REF_LOCAL_P (sym))		\
621 	 || ((GET_CODE (sym) == CONST)					\
622 	     && SYMBOL_REF_P (XEXP (XEXP (sym, 0),0))			\
623 	     && SYMBOL_REF_LOCAL_P (XEXP (XEXP (sym, 0),0)))))		\
624      || riscv_cmodel == CM_MEDANY))
625 
626 /* Define this as 1 if `char' should by default be signed; else as 0.  */
627 #define DEFAULT_SIGNED_CHAR 0
628 
629 #define MOVE_MAX UNITS_PER_WORD
630 #define MAX_MOVE_MAX 8
631 
632 /* The SPARC port says:
633    Nonzero if access to memory by bytes is slow and undesirable.
634    For RISC chips, it means that access to memory by bytes is no
635    better than access by words when possible, so grab a whole word
636    and maybe make use of that.  */
637 #define SLOW_BYTE_ACCESS 1
638 
639 /* Using SHIFT_COUNT_TRUNCATED is discouraged, so we handle this with patterns
640    in the md file instead.  */
641 #define SHIFT_COUNT_TRUNCATED 0
642 
643 /* Specify the machine mode that pointers have.
644    After generation of rtl, the compiler makes no further distinction
645    between pointers and any other objects of this machine mode.  */
646 
647 #define Pmode word_mode
648 
649 /* Give call MEMs SImode since it is the "most permissive" mode
650    for both 32-bit and 64-bit targets.  */
651 
652 #define FUNCTION_MODE SImode
653 
654 /* A C expression for the cost of a branch instruction.  A value of 2
655    seems to minimize code size.  */
656 
657 #define BRANCH_COST(speed_p, predictable_p) \
658   ((!(speed_p) || (predictable_p)) ? 2 : riscv_branch_cost)
659 
660 #define LOGICAL_OP_NON_SHORT_CIRCUIT 0
661 
662 /* Control the assembler format that we output.  */
663 
664 /* Output to assembler file text saying following lines
665    may contain character constants, extra white space, comments, etc.  */
666 
667 #ifndef ASM_APP_ON
668 #define ASM_APP_ON " #APP\n"
669 #endif
670 
671 /* Output to assembler file text saying following lines
672    no longer contain unusual constructs.  */
673 
674 #ifndef ASM_APP_OFF
675 #define ASM_APP_OFF " #NO_APP\n"
676 #endif
677 
678 #define REGISTER_NAMES						\
679 { "zero","ra",  "sp",  "gp",  "tp",  "t0",  "t1",  "t2",	\
680   "s0",  "s1",  "a0",  "a1",  "a2",  "a3",  "a4",  "a5",	\
681   "a6",  "a7",  "s2",  "s3",  "s4",  "s5",  "s6",  "s7",	\
682   "s8",  "s9",  "s10", "s11", "t3",  "t4",  "t5",  "t6",	\
683   "ft0", "ft1", "ft2", "ft3", "ft4", "ft5", "ft6", "ft7",	\
684   "fs0", "fs1", "fa0", "fa1", "fa2", "fa3", "fa4", "fa5",	\
685   "fa6", "fa7", "fs2", "fs3", "fs4", "fs5", "fs6", "fs7",	\
686   "fs8", "fs9", "fs10","fs11","ft8", "ft9", "ft10","ft11",	\
687   "arg", "frame", }
688 
689 #define ADDITIONAL_REGISTER_NAMES					\
690 {									\
691   { "x0",	 0 + GP_REG_FIRST },					\
692   { "x1",	 1 + GP_REG_FIRST },					\
693   { "x2",	 2 + GP_REG_FIRST },					\
694   { "x3",	 3 + GP_REG_FIRST },					\
695   { "x4",	 4 + GP_REG_FIRST },					\
696   { "x5",	 5 + GP_REG_FIRST },					\
697   { "x6",	 6 + GP_REG_FIRST },					\
698   { "x7",	 7 + GP_REG_FIRST },					\
699   { "x8",	 8 + GP_REG_FIRST },					\
700   { "x9",	 9 + GP_REG_FIRST },					\
701   { "x10",	10 + GP_REG_FIRST },					\
702   { "x11",	11 + GP_REG_FIRST },					\
703   { "x12",	12 + GP_REG_FIRST },					\
704   { "x13",	13 + GP_REG_FIRST },					\
705   { "x14",	14 + GP_REG_FIRST },					\
706   { "x15",	15 + GP_REG_FIRST },					\
707   { "x16",	16 + GP_REG_FIRST },					\
708   { "x17",	17 + GP_REG_FIRST },					\
709   { "x18",	18 + GP_REG_FIRST },					\
710   { "x19",	19 + GP_REG_FIRST },					\
711   { "x20",	20 + GP_REG_FIRST },					\
712   { "x21",	21 + GP_REG_FIRST },					\
713   { "x22",	22 + GP_REG_FIRST },					\
714   { "x23",	23 + GP_REG_FIRST },					\
715   { "x24",	24 + GP_REG_FIRST },					\
716   { "x25",	25 + GP_REG_FIRST },					\
717   { "x26",	26 + GP_REG_FIRST },					\
718   { "x27",	27 + GP_REG_FIRST },					\
719   { "x28",	28 + GP_REG_FIRST },					\
720   { "x29",	29 + GP_REG_FIRST },					\
721   { "x30",	30 + GP_REG_FIRST },					\
722   { "x31",	31 + GP_REG_FIRST },					\
723   { "f0",	 0 + FP_REG_FIRST },					\
724   { "f1",	 1 + FP_REG_FIRST },					\
725   { "f2",	 2 + FP_REG_FIRST },					\
726   { "f3",	 3 + FP_REG_FIRST },					\
727   { "f4",	 4 + FP_REG_FIRST },					\
728   { "f5",	 5 + FP_REG_FIRST },					\
729   { "f6",	 6 + FP_REG_FIRST },					\
730   { "f7",	 7 + FP_REG_FIRST },					\
731   { "f8",	 8 + FP_REG_FIRST },					\
732   { "f9",	 9 + FP_REG_FIRST },					\
733   { "f10",	10 + FP_REG_FIRST },					\
734   { "f11",	11 + FP_REG_FIRST },					\
735   { "f12",	12 + FP_REG_FIRST },					\
736   { "f13",	13 + FP_REG_FIRST },					\
737   { "f14",	14 + FP_REG_FIRST },					\
738   { "f15",	15 + FP_REG_FIRST },					\
739   { "f16",	16 + FP_REG_FIRST },					\
740   { "f17",	17 + FP_REG_FIRST },					\
741   { "f18",	18 + FP_REG_FIRST },					\
742   { "f19",	19 + FP_REG_FIRST },					\
743   { "f20",	20 + FP_REG_FIRST },					\
744   { "f21",	21 + FP_REG_FIRST },					\
745   { "f22",	22 + FP_REG_FIRST },					\
746   { "f23",	23 + FP_REG_FIRST },					\
747   { "f24",	24 + FP_REG_FIRST },					\
748   { "f25",	25 + FP_REG_FIRST },					\
749   { "f26",	26 + FP_REG_FIRST },					\
750   { "f27",	27 + FP_REG_FIRST },					\
751   { "f28",	28 + FP_REG_FIRST },					\
752   { "f29",	29 + FP_REG_FIRST },					\
753   { "f30",	30 + FP_REG_FIRST },					\
754   { "f31",	31 + FP_REG_FIRST },					\
755 }
756 
757 /* Globalizing directive for a label.  */
758 #define GLOBAL_ASM_OP "\t.globl\t"
759 
760 /* This is how to store into the string LABEL
761    the symbol_ref name of an internal numbered label where
762    PREFIX is the class of label and NUM is the number within the class.
763    This is suitable for output with `assemble_name'.  */
764 
765 #undef ASM_GENERATE_INTERNAL_LABEL
766 #define ASM_GENERATE_INTERNAL_LABEL(LABEL,PREFIX,NUM)			\
767   sprintf ((LABEL), "*%s%s%ld", (LOCAL_LABEL_PREFIX), (PREFIX), (long)(NUM))
768 
769 /* This is how to output an element of a case-vector that is absolute.  */
770 
771 #define ASM_OUTPUT_ADDR_VEC_ELT(STREAM, VALUE)				\
772   fprintf (STREAM, "\t.word\t%sL%d\n", LOCAL_LABEL_PREFIX, VALUE)
773 
774 /* This is how to output an element of a PIC case-vector. */
775 
776 #define ASM_OUTPUT_ADDR_DIFF_ELT(STREAM, BODY, VALUE, REL)		\
777   fprintf (STREAM, "\t.word\t%sL%d-%sL%d\n",				\
778 	   LOCAL_LABEL_PREFIX, VALUE, LOCAL_LABEL_PREFIX, REL)
779 
780 /* This is how to output an assembler line
781    that says to advance the location counter
782    to a multiple of 2**LOG bytes.  */
783 
784 #define ASM_OUTPUT_ALIGN(STREAM,LOG)					\
785   fprintf (STREAM, "\t.align\t%d\n", (LOG))
786 
787 /* Define the strings to put out for each section in the object file.  */
788 #define TEXT_SECTION_ASM_OP	"\t.text"	/* instructions */
789 #define DATA_SECTION_ASM_OP	"\t.data"	/* large data */
790 #define READONLY_DATA_SECTION_ASM_OP	"\t.section\t.rodata"
791 #define BSS_SECTION_ASM_OP	"\t.bss"
792 #define SBSS_SECTION_ASM_OP	"\t.section\t.sbss,\"aw\",@nobits"
793 #define SDATA_SECTION_ASM_OP	"\t.section\t.sdata,\"aw\",@progbits"
794 
795 #define ASM_OUTPUT_REG_PUSH(STREAM,REGNO)				\
796 do									\
797   {									\
798     fprintf (STREAM, "\taddi\t%s,%s,-8\n\t%s\t%s,0(%s)\n",		\
799 	     reg_names[STACK_POINTER_REGNUM],				\
800 	     reg_names[STACK_POINTER_REGNUM],				\
801 	     TARGET_64BIT ? "sd" : "sw",				\
802 	     reg_names[REGNO],						\
803 	     reg_names[STACK_POINTER_REGNUM]);				\
804   }									\
805 while (0)
806 
807 #define ASM_OUTPUT_REG_POP(STREAM,REGNO)				\
808 do									\
809   {									\
810     fprintf (STREAM, "\t%s\t%s,0(%s)\n\taddi\t%s,%s,8\n",		\
811 	     TARGET_64BIT ? "ld" : "lw",				\
812 	     reg_names[REGNO],						\
813 	     reg_names[STACK_POINTER_REGNUM],				\
814 	     reg_names[STACK_POINTER_REGNUM],				\
815 	     reg_names[STACK_POINTER_REGNUM]);				\
816   }									\
817 while (0)
818 
819 #define ASM_COMMENT_START "#"
820 
821 #undef SIZE_TYPE
822 #define SIZE_TYPE (POINTER_SIZE == 64 ? "long unsigned int" : "unsigned int")
823 
824 #undef PTRDIFF_TYPE
825 #define PTRDIFF_TYPE (POINTER_SIZE == 64 ? "long int" : "int")
826 
827 /* The maximum number of bytes copied by one iteration of a movmemsi loop.  */
828 
829 #define RISCV_MAX_MOVE_BYTES_PER_LOOP_ITER (UNITS_PER_WORD * 4)
830 
831 /* The maximum number of bytes that can be copied by a straight-line
832    movmemsi implementation.  */
833 
834 #define RISCV_MAX_MOVE_BYTES_STRAIGHT (RISCV_MAX_MOVE_BYTES_PER_LOOP_ITER * 3)
835 
836 /* If a memory-to-memory move would take MOVE_RATIO or more simple
837    move-instruction pairs, we will do a movmem or libcall instead.
838    Do not use move_by_pieces at all when strict alignment is not
839    in effect but the target has slow unaligned accesses; in this
840    case, movmem or libcall is more efficient.  */
841 
842 #define MOVE_RATIO(speed)						\
843   (!STRICT_ALIGNMENT && riscv_slow_unaligned_access_p ? 1 :		\
844    (speed) ? RISCV_MAX_MOVE_BYTES_PER_LOOP_ITER / UNITS_PER_WORD :	\
845    CLEAR_RATIO (speed) / 2)
846 
847 /* For CLEAR_RATIO, when optimizing for size, give a better estimate
848    of the length of a memset call, but use the default otherwise.  */
849 
850 #define CLEAR_RATIO(speed) ((speed) ? 16 : 6)
851 
852 /* This is similar to CLEAR_RATIO, but for a non-zero constant, so when
853    optimizing for size adjust the ratio to account for the overhead of
854    loading the constant and replicating it across the word.  */
855 
856 #define SET_RATIO(speed) (CLEAR_RATIO (speed) - ((speed) ? 0 : 2))
857 
858 #ifndef USED_FOR_TARGET
859 extern const enum reg_class riscv_regno_to_class[];
860 extern bool riscv_slow_unaligned_access_p;
861 extern unsigned riscv_stack_boundary;
862 #endif
863 
864 #define ASM_PREFERRED_EH_DATA_FORMAT(CODE,GLOBAL) \
865   (((GLOBAL) ? DW_EH_PE_indirect : 0) | DW_EH_PE_pcrel | DW_EH_PE_sdata4)
866 
867 #define XLEN_SPEC \
868   "%{march=rv32*:32}" \
869   "%{march=rv64*:64}" \
870 
871 #define ABI_SPEC \
872   "%{mabi=ilp32:ilp32}" \
873   "%{mabi=ilp32f:ilp32f}" \
874   "%{mabi=ilp32d:ilp32d}" \
875   "%{mabi=lp64:lp64}" \
876   "%{mabi=lp64f:lp64f}" \
877   "%{mabi=lp64d:lp64d}" \
878 
879 #define STARTFILE_PREFIX_SPEC 			\
880    "/lib" XLEN_SPEC "/" ABI_SPEC "/ "		\
881    "/usr/lib" XLEN_SPEC "/" ABI_SPEC "/ "	\
882    "/lib/ "					\
883    "/usr/lib/ "
884 
885 /* ISA constants needed for code generation.  */
886 #define OPCODE_LW    0x2003
887 #define OPCODE_LD    0x3003
888 #define OPCODE_AUIPC 0x17
889 #define OPCODE_JALR  0x67
890 #define OPCODE_LUI   0x37
891 #define OPCODE_ADDI  0x13
892 #define SHIFT_RD  7
893 #define SHIFT_RS1 15
894 #define SHIFT_IMM 20
895 #define IMM_BITS 12
896 #define C_SxSP_BITS 6
897 
898 #define IMM_REACH (1LL << IMM_BITS)
899 #define CONST_HIGH_PART(VALUE) (((VALUE) + (IMM_REACH/2)) & ~(IMM_REACH-1))
900 #define CONST_LOW_PART(VALUE) ((VALUE) - CONST_HIGH_PART (VALUE))
901 
902 #define SWSP_REACH (4LL << C_SxSP_BITS)
903 #define SDSP_REACH (8LL << C_SxSP_BITS)
904 
905 #endif /* ! GCC_RISCV_H */
906