/* Definitions of target machine for GNU compiler, for CR16.
   Copyright (C) 2012-2021 Free Software Foundation, Inc.
   Contributed by KPIT Cummins Infosystems Limited.

   This file is part of GCC.

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

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

   You should have received a copy of the GNU General Public License
   along with GCC; see the file COPYING3.  If not see
   <http://www.gnu.org/licenses/>.  */
   
#ifndef GCC_CR16_H
#define GCC_CR16_H

#define OBJECT_FORMAT_ELF

/* Controlling the driver.  */

/* The GNU C++ standard library requires that these macros be defined.  */
#undef CPLUSPLUS_CPP_SPEC
#define CPLUSPLUS_CPP_SPEC "-D_GNU_SOURCE %(cpp)"

#undef  STARTFILE_SPEC
#define STARTFILE_SPEC "crt1.o%s crti.o%s crtbegin.o%s crtlibid.o%s"

#undef  ENDFILE_SPEC
#define ENDFILE_SPEC "crtend.o%s crtn.o%s"

#undef  MATH_LIBRARY
#define MATH_LIBRARY ""

#undef  LIB_SPEC
#define LIB_SPEC "-( -lc %{msim*:-lsim}%{!msim*:-lnosys} -) \
%{msim*:%{!T*:-Tsim.ld}} \
%{!T*:%{!msim*: %{-Telf32cr16.x}}}"

/* Run-time target specification.  */
#ifndef TARGET_CPU_CPP_BUILTINS
#define TARGET_CPU_CPP_BUILTINS()          \
do                                         \
  {                                        \
    builtin_define ("__CR__");             \
    builtin_define ("__CR16__");           \
    builtin_define ("__CR16C__");          \
    if (TARGET_CR16CP)                     \
      builtin_define ("__CR16CP__");       \
    else                                   \
      builtin_define ("__CR16CSTD__");     \
    if (CR16_TARGET_DATA_NEAR)             \
      builtin_define ("__DATA_NEAR__");    \
    if (CR16_TARGET_DATA_MEDIUM)           \
      builtin_define ("__DATA_MEDIUM__");  \
    if (CR16_TARGET_DATA_FAR)              \
      builtin_define ("__DATA_FAR__");     \
    if (TARGET_INT32)                      \
      builtin_define ("__INT32__");        \
  }                                        \
while (0)
#endif

/* Force the generation of dwarf .debug_frame sections even if not
   compiling -g.  This guarantees that we can unwind the stack.  */
#define DWARF2_FRAME_INFO 1

#define PREFERRED_DEBUGGING_TYPE DWARF2_DEBUG

/* Generate .file/.loc directives, so that the assembler generates the
   line table.  */
#define DWARF2_ASM_LINE_DEBUG_INFO 1

#define CR16_TARGET_DATA_NEAR   cr16_is_data_model (DM_NEAR)
#define CR16_TARGET_DATA_MEDIUM cr16_is_data_model (DM_DEFAULT)
#define CR16_TARGET_DATA_FAR    cr16_is_data_model (DM_FAR)

/* Storage layout.  */
#define BITS_BIG_ENDIAN     0

#define BYTES_BIG_ENDIAN    0

#define WORDS_BIG_ENDIAN    0

#define UNITS_PER_WORD      2

/* Units per 32-bit (DWORD).  */
#define CR16_UNITS_PER_DWORD 4

#define POINTER_SIZE        32

#define PARM_BOUNDARY       16

#define STACK_BOUNDARY      (MAX (BIGGEST_ALIGNMENT, PARM_BOUNDARY))

#define FUNCTION_BOUNDARY   BIGGEST_ALIGNMENT

/* Biggest alignment on CR16C+ is 32-bit as internal bus is AMBA based 
   where as CR16C is proprietary internal bus architecture.  */
#define BIGGEST_ALIGNMENT   ((TARGET_CR16CP) ? 32 : 16)

#define MAX_FIXED_MODE_SIZE 64

/* In CR16 arrays of chars are word-aligned, so strcpy () will be faster.  */
#define DATA_ALIGNMENT(TYPE, ALIGN)              \
  (((TREE_CODE (TYPE) == ARRAY_TYPE)             \
     && (TYPE_MODE (TREE_TYPE (TYPE)) == QImode) \
     && ((ALIGN) < BITS_PER_WORD))               \
     ? (BITS_PER_WORD) : (ALIGN))

#define STRICT_ALIGNMENT 0

#define PCC_BITFIELD_TYPE_MATTERS 1

/* Layout of source language data types.  */
#define INT_TYPE_SIZE       (TARGET_INT32 ? 32 : 16)

#define SHORT_TYPE_SIZE     16

#define LONG_TYPE_SIZE      32

#define LONG_LONG_TYPE_SIZE 64

#define FLOAT_TYPE_SIZE     32

#define DOUBLE_TYPE_SIZE    64

#define LONG_DOUBLE_TYPE_SIZE 64

#define DEFAULT_SIGNED_CHAR 1

#define SIZE_TYPE           "long unsigned int"

#define PTRDIFF_TYPE        "long int"

#define WCHAR_TYPE          "short unsigned int"

#define WCHAR_TYPE_SIZE     16

/* By default, the C++ compiler will use the lowest bit of the pointer
   to function to indicate a pointer-to-member-function points to a
   virtual member function.  However, in CR architecture FUNCTION_BOUNDARY
   indicates function addresses are always even, but function pointers can be
   odd (after right-shifting them when loading them into a register), and the
   default doesn't work.  In that case, the lowest bit of the delta
   field will be used (the remainder of the field is shifted to the left).  */
#define TARGET_PTRMEMFUNC_VBIT_LOCATION     ptrmemfunc_vbit_in_delta

/* Define DEFAULT_PCC_STRUCT_RETURN to 1 if all structure and union return
   values must be in memory.  */
#define DEFAULT_PCC_STRUCT_RETURN 0

/* Register usage.  */

/* First 32-bit register is R12.  */
#define CR16_FIRST_DWORD_REGISTER   12

#define FIRST_PSEUDO_REGISTER       16

/* 1 for registers that have pervasive standard uses
   and are not available for the register allocator.
   On the CR16, only the stack pointer (r15) is such.  */
#define FIXED_REGISTERS                               \
  {                                                   \
  /* r0  r1  r2  r3  r4  r5  r6  r7  r8  r9  r10.  */ \
    0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,        \
  /* r11 r12 r13 ra  sp.  */                          \
    0,  0,  0,  0,  1                                 \
  }      

/* 1 for registers not available across function calls.
   These must include the FIXED_REGISTERS and also any
   registers that can be used without being saved.
   The latter must include the registers where values are returned
   and the register where structure-value addresses are passed.
 
   On the CR16, calls clobbers r0-r6 (scratch registers), 
   ra (the return address) and sp (the stack pointer).  */
#define CALL_USED_REGISTERS                           \
  {                                                   \
  /* r0  r1  r2  r3  r4  r5  r6  r7  r8  r9  r10.  */ \
    1,  1,  1,  1,  1,  1,  1,  0,  0,  0,  0,        \
  /* r11 r12 r13 ra  sp.  */                          \
    0,  0,  0,  1,  1                                 \
  }

/* Returns 1 if the register is longer than word size, 0 otherwise.  */
#define LONG_REG_P(REGNO)                                                    \
  (targetm.hard_regno_nregs (REGNO,                                          \
			     GET_MODE_WIDER_MODE (word_mode).require ()) == 1)

/* Interrupt functions can only use registers that have already been 
   saved by the prologue, even if they would normally be call-clobbered 
   Check if sizes are same and then check if it is possible to rename.  */
#define HARD_REGNO_RENAME_OK(SRC, DEST)                 \
  (!cr16_interrupt_function_p () || (df_regs_ever_live_p (DEST)))

/* Exception handling stuff.  */

/*To ensure correct dwarf unwinding.  */
#define LIBGCC2_UNWIND_ATTRIBUTE __attribute__((optimize ("no-gcse","no-dse")))

#define gen_rtx_RA	gen_rtx_REG (Pmode, RETURN_ADDRESS_REGNUM)

/* Use (r8,r7) and (r10,r9) to pass exception handling information.  */
#define EH_RETURN_DATA_REGNO(N) (((N) < 2) ? (N*2 + 7) : INVALID_REGNUM)

#define DWARF2_UNWIND_INFO 1

/* (r5,r4) holds a stack adjustment for returning to a handler.  */
#define EH_RETURN_STACKADJ_RTX 		gen_rtx_REG (Pmode, 4)

#define EH_RETURN_HANDLER_RTX \
  gen_rtx_MEM (Pmode, plus_constant (Pmode, arg_pointer_rtx, -4))

#define INCOMING_RETURN_ADDR_RTX	gen_rtx_RA

#define DWARF_FRAME_RETURN_COLUMN	\
  DWARF_FRAME_REGNUM (RETURN_ADDRESS_REGNUM)

#define INCOMING_FRAME_SP_OFFSET		0	
#define FRAME_POINTER_CFA_OFFSET(FNDECL)	0	

/* A C expression whose value is RTL representing the value of the return
   address for the frame COUNT steps up from the current frame.  */
#define RETURN_ADDR_RTX(COUNT, FRAME) 			  		\
  (COUNT == 0)	?  gen_rtx_PLUS (Pmode, gen_rtx_RA, gen_rtx_RA)		\
		:  const0_rtx

enum reg_class
{
  NO_REGS,
  SHORT_REGS,
  LONG_REGS,
  NOSP_REGS,
  DOUBLE_BASE_REGS,
  GENERAL_REGS,
  ALL_REGS,
  LIM_REG_CLASSES
};

#define N_REG_CLASSES (int) LIM_REG_CLASSES

#define REG_CLASS_NAMES	\
  {			\
    "NO_REGS",		\
    "SHORT_REGS",	\
    "LONG_REGS",	\
    "NOSP_REGS",	\
    "DOUBLE_BASE_REGS",	\
    "GENERAL_REGS",	\
    "ALL_REGS"		\
  }

#define REG_CLASS_CONTENTS			     		\
  {						     		\
    {0x00000000}, /* NO_REGS		             */  	\
    {0x00000FFF}, /* SHORT_REGS 	: 0 - 11     */   	\
    {0x0000F000}, /* LONG_REGS 		: 12 - 15    */  	\
    {0x00007FFF}, /* NOSP_REGS 		: 0 - 14     */   	\
    {0x0000F555}, /* DOUBLE_BASE_REGS   : 2,4,6,8,10 */  	\
    {0x0000FFFF}, /* GENERAL_REGS	: 0 - 15     */  	\
    {0x0000FFFF}  /* ALL_REGS 		: 0 - 15     */  	\
  }

#define TARGET_SMALL_REGISTER_CLASSES_FOR_MODE_P  hook_bool_mode_true 

#define REGNO_REG_CLASS(REGNO)  cr16_regno_reg_class (REGNO)

#define BASE_REG_CLASS      GENERAL_REGS

#define MODE_BASE_REG_CLASS(MODE) \
  (GET_MODE_SIZE (MODE) <= 4 ?  (BASE_REG_CLASS) :  (DOUBLE_BASE_REGS))

#define INDEX_REG_CLASS      LONG_REGS

#define CR16_REGNO_OK_FOR_BASE_P(REGNO)                  \
  (((REGNO) < FIRST_PSEUDO_REGISTER)                     \
     || (reg_renumber && ((unsigned) reg_renumber[REGNO] \
                        < FIRST_PSEUDO_REGISTER)))

/* Use even-numbered reg for 64-bit accesses.  */
#define REGNO_MODE_OK_FOR_BASE_P(REGNO, MODE)	  \
	(CR16_REGNO_OK_FOR_BASE_P(REGNO)  &&	  \
	  ((GET_MODE_SIZE (MODE) > 4  &&  	  \
	     (REGNO) < CR16_FIRST_DWORD_REGISTER) \
	     ? (((REGNO) & 1) == 0) 		  \
	     : 1))

/* TODO: For now lets not support index addressing mode.  */
#define REGNO_OK_FOR_INDEX_P(REGNO)        \
  (((REGNO >= CR16_FIRST_DWORD_REGISTER)   \
     && ((REGNO) < FIRST_PSEUDO_REGISTER)) \
   || (reg_renumber                        \
       && (((unsigned) reg_renumber[REGNO] >= CR16_FIRST_DWORD_REGISTER)  \
            && ((unsigned) reg_renumber[REGNO] < FIRST_PSEUDO_REGISTER))) \
  )

#define PREFERRED_RELOAD_CLASS(X, CLASS) CLASS

/* The maximum number of consecutive registers of class CLASS needed to
   hold a value of mode MODE.
   On the CompactRISC architecture, the size of MODE in words.
   The size of MODE in double words for the class LONG_REGS.

   The following check assumes if the class is not LONG_REGS, then
   all (NO_REGS, SHORT_REGS, NOSP_REGS and GENERAL_REGS) other classes are 
   short.  We may have to check if this can cause any degradation in 
   performance.  */
#define CLASS_MAX_NREGS(CLASS, MODE) \
  (CLASS == LONG_REGS \
   ? (GET_MODE_SIZE (MODE) + CR16_UNITS_PER_DWORD - 1) / CR16_UNITS_PER_DWORD\
   : (GET_MODE_SIZE (MODE) + UNITS_PER_WORD - 1) / UNITS_PER_WORD)

/* Macros to check the range of integers . These macros were used across
   the port, majorly in constraints.md, predicates.md files. */
#define SIGNED_INT_FITS_N_BITS(imm, N)           \
  ((((imm) < ((HOST_WIDE_INT) 1 << ((N) - 1)))       \
      && ((imm) >= -((HOST_WIDE_INT) 1 << ((N) - 1)))) ? 1 : 0)

#define UNSIGNED_INT_FITS_N_BITS(imm, N) \
  (((imm) < ((HOST_WIDE_INT) 1 << (N)) && (imm) >= (HOST_WIDE_INT) 0) ? 1 : 0)

#define IN_RANGE_P(VALUE, LOW, HIGH)                            \
  ((((HOST_WIDE_INT)(VALUE)) >= (HOST_WIDE_INT)(LOW))           \
   && (((HOST_WIDE_INT)(VALUE)) <= ((HOST_WIDE_INT)(HIGH))))

#define IN_RAN(VALUE, LOW, HIGH)                             \
  (((((HOST_WIDE_INT)(VALUE)) >= (HOST_WIDE_INT)(LOW))       \
   && (((HOST_WIDE_INT)(VALUE)) <= ((HOST_WIDE_INT)(HIGH)))) ? 1 : 0)

/* This check is for sbit/cbit instruction.  */
#define OK_FOR_Z(OP) \
  ((GET_CODE (OP) == MEM && GET_CODE (XEXP (OP, 0)) == CONST_INT) \
   || (GET_CODE (OP) == MEM && GET_CODE (XEXP (OP, 0)) == REG) \
   || (GET_CODE (OP) == MEM && GET_CODE (XEXP (OP, 0)) == PLUS \
       && GET_CODE (XEXP ((XEXP (OP, 0)), 0)) == REG \
       && GET_CODE (XEXP ((XEXP (OP, 0)), 1)) == CONST_INT))

/* Stack layout and calling conventions.  */
#define STACK_GROWS_DOWNWARD 1

#define STACK_POINTER_REGNUM    15

#define FRAME_POINTER_REGNUM    13

#define ARG_POINTER_REGNUM      12

#define STATIC_CHAIN_REGNUM     1

#define RETURN_ADDRESS_REGNUM   14

#define FIRST_PARM_OFFSET(FNDECL) 0

#define ELIMINABLE_REGS                            \
  {                                                \
    { ARG_POINTER_REGNUM,   STACK_POINTER_REGNUM}, \
    { ARG_POINTER_REGNUM,   FRAME_POINTER_REGNUM}, \
    { FRAME_POINTER_REGNUM, STACK_POINTER_REGNUM}  \
  }

#define INITIAL_ELIMINATION_OFFSET(FROM, TO, OFFSET)              \
  do                                                              \
    {                                                             \
      (OFFSET) = cr16_initial_elimination_offset ((FROM), (TO));  \
    }                                                             \
  while (0)

/* Passing function arguments.  */

#define ACCUMULATE_OUTGOING_ARGS 0

#define PUSH_ROUNDING(BYTES) cr16_push_rounding (BYTES)

#ifndef CUMULATIVE_ARGS
struct cumulative_args
{
  int ints;
  int last_parm_in_reg;
};

#define CUMULATIVE_ARGS struct cumulative_args
#endif

/* On the CR16 architecture, Varargs routines should receive their parameters 
   on the stack.  */

#define INIT_CUMULATIVE_ARGS(CUM, FNTYPE, LIBNAME, FNDECL, N_NAMED_ARGS) \
  cr16_init_cumulative_args (&(CUM), (FNTYPE), (LIBNAME))

#define FUNCTION_ARG_REGNO_P(REGNO)  cr16_function_arg_regno_p (REGNO)

/* Generating code for profiling - NOT IMPLEMENTED.  */
#undef  FUNCTION_PROFILER
#define FUNCTION_PROFILER(STREAM, LABELNO)      \
{                                               \
  sorry ("profiler support for CR16");          \
}

/* Trampolines for nested functions - NOT SUPPORTED.  */
#define TRAMPOLINE_SIZE    16

/* ADDRESSING MODES.  */

#define CONSTANT_ADDRESS_P(X)       \
  (GET_CODE (X) == LABEL_REF        \
   || GET_CODE (X) == SYMBOL_REF    \
   || GET_CODE (X) == CONST         \
   || GET_CODE (X) == CONST_INT)

#define MAX_REGS_PER_ADDRESS    2

#define HAVE_POST_INCREMENT     0
#define HAVE_POST_DECREMENT     0
#define HAVE_POST_MODIFY_DISP   0
#define HAVE_POST_MODIFY_REG    0

#ifdef REG_OK_STRICT
#define CR16_REG_OK_FOR_BASE_P(X)	CR16_REGNO_OK_FOR_BASE_P (REGNO (X))
#define REG_MODE_OK_FOR_BASE_P(X, MODE)	\
  REGNO_MODE_OK_FOR_BASE_P (REGNO(X), MODE)
#define REG_OK_FOR_INDEX_P(X)   REGNO_OK_FOR_INDEX_P (REGNO (X))
#else /* not REG_OK_STRICT.  */
#define CR16_REG_OK_FOR_BASE_P(X)	1
#define REG_MODE_OK_FOR_BASE_P(X, MODE)	1
#define REG_OK_FOR_INDEX_P(X)   1
#endif /* not REG_OK_STRICT.  */

/* Assume best case (branch predicted).  */
#define BRANCH_COST(speed_p, predictable_p)       2

#define SLOW_BYTE_ACCESS  1

/* It is as good or better to call a constant function address than to
   call an address kept in a register.  */
#define NO_FUNCTION_CSE 1

/* Dividing the output into sections.  */

#define TEXT_SECTION_ASM_OP "\t.section\t.text"

#define DATA_SECTION_ASM_OP "\t.section\t.data"

#define BSS_SECTION_ASM_OP  "\t.section\t.bss"

/* Position independent code (PIC).  */
/* NEAR_PIC for -fpic option.  */

#define NEAR_PIC 1
                                      
/* FAR_PIC for -fPIC option.  */                                                                                       

#define FAR_PIC  2

#define PIC_OFFSET_TABLE_REGNUM  12

#define LEGITIMATE_PIC_OPERAND_P(X) legitimate_pic_operand_p (X)       

/* Assembler format.  */

/* Character to start a comment.  */
#define ASM_COMMENT_START "#"

#define GLOBAL_ASM_OP "\t.globl\t"

#undef USER_LABEL_PREFIX
#define USER_LABEL_PREFIX "_"

#undef ASM_OUTPUT_LABELREF
#define ASM_OUTPUT_LABELREF(STREAM, NAME) \
  asm_fprintf (STREAM, "%U%s", (*targetm.strip_name_encoding) (NAME))

#define ASM_OUTPUT_SYMBOL_REF(STREAM, SYMBOL)   \
  do                                            \
    {                                           \
      const char *rn = XSTR (SYMBOL, 0);        \
      assemble_name (STREAM, rn);               \
      if (SYMBOL_REF_FUNCTION_P (SYMBOL))       \
      {                                         \
        fprintf ((STREAM), "@c");               \
      }                                         \
    }                                           \
  while (0)

#undef ASM_APP_ON
#define ASM_APP_ON   "#APP\n"

#undef ASM_APP_OFF
#define ASM_APP_OFF  "#NO_APP\n"

/* Switch into a generic section.  */
#define TARGET_ASM_NAMED_SECTION	default_elf_asm_named_section

#undef INIT_SECTION_ASM_OP
#define INIT_SECTION_ASM_OP		"\t.section\t.init"

#undef FINI_SECTION_ASM_OP
#define FINI_SECTION_ASM_OP		"\t.section\t.fini"

/* Instruction output.  */

#define REGISTER_NAMES                                     \
  {                                                        \
    "r0",  "r1",  "r2",  "r3",  "r4",  "r5",  "r6",  "r7", \
    "r8",  "r9",  "r10", "r11", "r12", "r13", "ra",  "sp"  \
  }

/* Output of dispatch tables.  */

/* Revisit. No PC relative case as label expressions are not 
   properly supported in binutils else we could have done this:
   #define CASE_VECTOR_PC_RELATIVE (optimize_size ? 1 : 0).  */
#define CASE_VECTOR_PC_RELATIVE 0

#define ASM_OUTPUT_ADDR_DIFF_ELT(FILE, BODY, VALUE, REL)    \
  ((GET_MODE (BODY) == QImode)                              \
   ? fprintf ((FILE), "\t.byte (.L%d-.L%d) >> 1\n",         \
              VALUE, REL)                                   \
   : fprintf ((FILE), "\t.word (.L%d-.L%d) >> 1\n",         \
              VALUE, REL))

#define ASM_OUTPUT_ADDR_VEC_ELT(STREAM, VALUE) \
  asm_fprintf ((STREAM), "\t.long\t.L%d@c\n", (VALUE))

/* Alignment in assembler file.  */

#define ASM_OUTPUT_ALIGN(STREAM, POWER) \
  asm_fprintf ((STREAM), "\t.align\t%d\n", 1 << (POWER))

/* Miscellaneous parameters.  */

#define CASE_VECTOR_MODE  Pmode

#define MOVE_MAX 4

#define STORE_FLAG_VALUE  1

#define Pmode SImode

#define FUNCTION_MODE QImode

/* Define this boolean macro(s) to indicate whether or not your architecture
   has (un)conditional branches that can span all of memory.  It is used in
   conjunction with an optimization that partitions hot and cold basic blocks
   into separate sections of the executable.
   CR16 contains branch instructions that span whole address space.  */
#define HAS_LONG_COND_BRANCH    1
#define HAS_LONG_UNCOND_BRANCH  1

#endif /* End of GCC_CR16_H.  */