path: root/gcc/config/s390/s390.h

/* Definitions of target machine for GNU compiler, for IBM S/390
   Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006,
   2007, 2008, 2009, 2010 Free Software Foundation, Inc.
   Contributed by Hartmut Penner (hpenner@de.ibm.com) and
                  Ulrich Weigand (uweigand@de.ibm.com).
                  Andreas Krebbel (Andreas.Krebbel@de.ibm.com)

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 _S390_H
#define _S390_H

/* Which processor to generate code or schedule for. The cpu attribute
   defines a list that mirrors this list, so changes to s390.md must be
   made at the same time.  */

enum processor_type
{
  PROCESSOR_9672_G5,
  PROCESSOR_9672_G6,
  PROCESSOR_2064_Z900,
  PROCESSOR_2084_Z990,
  PROCESSOR_2094_Z9_109,
  PROCESSOR_2097_Z10,
  PROCESSOR_max
};

/* Optional architectural facilities supported by the processor.  */

enum processor_flags
{
  PF_IEEE_FLOAT = 1,
  PF_ZARCH = 2,
  PF_LONG_DISPLACEMENT = 4,
  PF_EXTIMM = 8,
  PF_DFP = 16,
  PF_Z10 = 32
};

extern enum processor_type s390_tune;
extern int s390_tune_flags;

/* This is necessary to avoid a warning about comparing different enum
   types.  */
#define s390_tune_attr ((enum attr_cpu)s390_tune)

extern enum processor_type s390_arch;
extern int s390_arch_flags;

/* These flags indicate that the generated code should run on a cpu
   providing the respective hardware facility regardless of the
   current cpu mode (ESA or z/Architecture).  */

#define TARGET_CPU_IEEE_FLOAT \
	(s390_arch_flags & PF_IEEE_FLOAT)
#define TARGET_CPU_ZARCH \
	(s390_arch_flags & PF_ZARCH)
#define TARGET_CPU_LONG_DISPLACEMENT \
	(s390_arch_flags & PF_LONG_DISPLACEMENT)
#define TARGET_CPU_EXTIMM \
 	(s390_arch_flags & PF_EXTIMM)
#define TARGET_CPU_DFP \
 	(s390_arch_flags & PF_DFP)
#define TARGET_CPU_Z10 \
 	(s390_arch_flags & PF_Z10)

/* These flags indicate that the generated code should run on a cpu
   providing the respective hardware facility when run in
   z/Architecture mode.  */

#define TARGET_LONG_DISPLACEMENT \
       (TARGET_ZARCH && TARGET_CPU_LONG_DISPLACEMENT)
#define TARGET_EXTIMM \
       (TARGET_ZARCH && TARGET_CPU_EXTIMM)
#define TARGET_DFP \
       (TARGET_ZARCH && TARGET_CPU_DFP && TARGET_HARD_FLOAT)
#define TARGET_Z10 \
       (TARGET_ZARCH && TARGET_CPU_Z10)

/* Run-time target specification.  */

/* Defaults for option flags defined only on some subtargets.  */
#ifndef TARGET_TPF_PROFILING
#define TARGET_TPF_PROFILING 0
#endif

/* This will be overridden by OS headers.  */
#define TARGET_TPF 0

/* Target CPU builtins.  */
#define TARGET_CPU_CPP_BUILTINS()			\
  do							\
    {							\
      builtin_assert ("cpu=s390");			\
      builtin_assert ("machine=s390");			\
      builtin_define ("__s390__");			\
      if (TARGET_ZARCH)					\
	builtin_define ("__zarch__");			\
      if (TARGET_64BIT)					\
        builtin_define ("__s390x__");			\
      if (TARGET_LONG_DOUBLE_128)			\
        builtin_define ("__LONG_DOUBLE_128__");		\
    }							\
  while (0)

#ifdef DEFAULT_TARGET_64BIT
#define TARGET_DEFAULT             (MASK_64BIT | MASK_ZARCH | MASK_HARD_DFP)
#else
#define TARGET_DEFAULT             0
#endif

/* Support for configure-time defaults.  */
#define OPTION_DEFAULT_SPECS 					\
  { "mode", "%{!mesa:%{!mzarch:-m%(VALUE)}}" },			\
  { "arch", "%{!march=*:-march=%(VALUE)}" },			\
  { "tune", "%{!mtune=*:-mtune=%(VALUE)}" }

/* Defaulting rules.  */
#ifdef DEFAULT_TARGET_64BIT
#define DRIVER_SELF_SPECS					\
  "%{!m31:%{!m64:-m64}}",					\
  "%{!mesa:%{!mzarch:%{m31:-mesa}%{m64:-mzarch}}}",		\
  "%{!march=*:%{mesa:-march=g5}%{mzarch:-march=z900}}"
#else
#define DRIVER_SELF_SPECS					\
  "%{!m31:%{!m64:-m31}}",					\
  "%{!mesa:%{!mzarch:%{m31:-mesa}%{m64:-mzarch}}}",		\
  "%{!march=*:%{mesa:-march=g5}%{mzarch:-march=z900}}"
#endif

/* Target version string.  Overridden by the OS header.  */
#ifdef DEFAULT_TARGET_64BIT
#define TARGET_VERSION fprintf (stderr, " (zSeries)");
#else
#define TARGET_VERSION fprintf (stderr, " (S/390)");
#endif

/* Frame pointer is not used for debugging.  */
#define CAN_DEBUG_WITHOUT_FP

/* Constants needed to control the TEST DATA CLASS (TDC) instruction.  */
#define S390_TDC_POSITIVE_ZERO                     (1 << 11)
#define S390_TDC_NEGATIVE_ZERO                     (1 << 10)
#define S390_TDC_POSITIVE_NORMALIZED_BFP_NUMBER    (1 << 9)
#define S390_TDC_NEGATIVE_NORMALIZED_BFP_NUMBER    (1 << 8)
#define S390_TDC_POSITIVE_DENORMALIZED_BFP_NUMBER  (1 << 7)
#define S390_TDC_NEGATIVE_DENORMALIZED_BFP_NUMBER  (1 << 6)
#define S390_TDC_POSITIVE_INFINITY                 (1 << 5)
#define S390_TDC_NEGATIVE_INFINITY                 (1 << 4)
#define S390_TDC_POSITIVE_QUIET_NAN                (1 << 3)
#define S390_TDC_NEGATIVE_QUIET_NAN                (1 << 2)
#define S390_TDC_POSITIVE_SIGNALING_NAN            (1 << 1)
#define S390_TDC_NEGATIVE_SIGNALING_NAN            (1 << 0)

/* The following values are different for DFP.  */
#define S390_TDC_POSITIVE_DENORMALIZED_DFP_NUMBER (1 << 9)
#define S390_TDC_NEGATIVE_DENORMALIZED_DFP_NUMBER (1 << 8)
#define S390_TDC_POSITIVE_NORMALIZED_DFP_NUMBER   (1 << 7)
#define S390_TDC_NEGATIVE_NORMALIZED_DFP_NUMBER   (1 << 6)

/* For signbit, the BFP-DFP-difference makes no difference. */
#define S390_TDC_SIGNBIT_SET (S390_TDC_NEGATIVE_ZERO \
                          | S390_TDC_NEGATIVE_NORMALIZED_BFP_NUMBER \
                          | S390_TDC_NEGATIVE_DENORMALIZED_BFP_NUMBER\
                          | S390_TDC_NEGATIVE_INFINITY \
                          | S390_TDC_NEGATIVE_QUIET_NAN \
			  | S390_TDC_NEGATIVE_SIGNALING_NAN )

#define S390_TDC_INFINITY (S390_TDC_POSITIVE_INFINITY \
			  | S390_TDC_NEGATIVE_INFINITY )

/* Target machine storage layout.  */

/* Everything is big-endian.  */
#define BITS_BIG_ENDIAN 1
#define BYTES_BIG_ENDIAN 1
#define WORDS_BIG_ENDIAN 1

#define STACK_SIZE_MODE (Pmode)

#ifndef IN_LIBGCC2

/* Width of a word, in units (bytes).  */
  #define UNITS_PER_WORD (TARGET_ZARCH ? 8 : 4)

/* Width of a pointer.  To be used instead of UNITS_PER_WORD in
   ABI-relevant contexts.  This always matches
   GET_MODE_SIZE (Pmode).  */
  #define UNITS_PER_LONG (TARGET_64BIT ? 8 : 4)
  #define MIN_UNITS_PER_WORD 4
  #define MAX_BITS_PER_WORD 64
#else

  /* In libgcc, UNITS_PER_WORD has ABI-relevant effects, e.g. whether
     the library should export TImode functions or not.  Thus, we have
     to redefine UNITS_PER_WORD depending on __s390x__ for libgcc.  */
  #ifdef __s390x__
    #define UNITS_PER_WORD 8
  #else
    #define UNITS_PER_WORD 4
  #endif
#endif

/* Width of a pointer, in bits.  */
#define POINTER_SIZE (TARGET_64BIT ? 64 : 32)

/* Allocation boundary (in *bits*) for storing arguments in argument list.  */
#define PARM_BOUNDARY (TARGET_64BIT ? 64 : 32)

/* Boundary (in *bits*) on which stack pointer should be aligned.  */
#define STACK_BOUNDARY 64

/* Allocation boundary (in *bits*) for the code of a function.  */
#define FUNCTION_BOUNDARY 32

/* There is no point aligning anything to a rounder boundary than this.  */
#define BIGGEST_ALIGNMENT 64

/* Alignment of field after `int : 0' in a structure.  */
#define EMPTY_FIELD_BOUNDARY 32

/* Alignment on even addresses for LARL instruction.  */
#define CONSTANT_ALIGNMENT(EXP, ALIGN) (ALIGN) < 16 ? 16 : (ALIGN)
#define DATA_ALIGNMENT(TYPE, ALIGN) (ALIGN) < 16 ? 16 : (ALIGN)

/* Alignment is not required by the hardware.  */
#define STRICT_ALIGNMENT 0

/* Mode of stack savearea.
   FUNCTION is VOIDmode because calling convention maintains SP.
   BLOCK needs Pmode for SP.
   NONLOCAL needs twice Pmode to maintain both backchain and SP.  */
#define STACK_SAVEAREA_MODE(LEVEL)      \
  (LEVEL == SAVE_FUNCTION ? VOIDmode    \
  : LEVEL == SAVE_NONLOCAL ? (TARGET_64BIT ? OImode : TImode) : Pmode)


/* Type layout.  */

/* Sizes in bits of the source language data types.  */
#define SHORT_TYPE_SIZE 16
#define INT_TYPE_SIZE 32
#define LONG_TYPE_SIZE (TARGET_64BIT ? 64 : 32)
#define LONG_LONG_TYPE_SIZE 64
#define FLOAT_TYPE_SIZE 32
#define DOUBLE_TYPE_SIZE 64
#define LONG_DOUBLE_TYPE_SIZE (TARGET_LONG_DOUBLE_128 ? 128 : 64)

/* Define this to set long double type size to use in libgcc2.c, which can
   not depend on target_flags.  */
#ifdef __LONG_DOUBLE_128__
#define LIBGCC2_LONG_DOUBLE_TYPE_SIZE 128
#else
#define LIBGCC2_LONG_DOUBLE_TYPE_SIZE 64
#endif

/* Work around target_flags dependency in ada/targtyps.c.  */
#define WIDEST_HARDWARE_FP_SIZE 64

/* We use "unsigned char" as default.  */
#define DEFAULT_SIGNED_CHAR 0


/* Register usage.  */

/* We have 16 general purpose registers (registers 0-15),
   and 16 floating point registers (registers 16-31).
   (On non-IEEE machines, we have only 4 fp registers.)

   Amongst the general purpose registers, some are used
   for specific purposes:
   GPR 11: Hard frame pointer (if needed)
   GPR 12: Global offset table pointer (if needed)
   GPR 13: Literal pool base register
   GPR 14: Return address register
   GPR 15: Stack pointer

   Registers 32-35 are 'fake' hard registers that do not
   correspond to actual hardware:
   Reg 32: Argument pointer
   Reg 33: Condition code
   Reg 34: Frame pointer
   Reg 35: Return address pointer

   Registers 36 and 37 are mapped to access registers
   0 and 1, used to implement thread-local storage.  */

#define FIRST_PSEUDO_REGISTER 38

/* Standard register usage.  */
#define GENERAL_REGNO_P(N)	((int)(N) >= 0 && (N) < 16)
#define ADDR_REGNO_P(N)		((N) >= 1 && (N) < 16)
#define FP_REGNO_P(N)		((N) >= 16 && (N) < 32)
#define CC_REGNO_P(N)		((N) == 33)
#define FRAME_REGNO_P(N)	((N) == 32 || (N) == 34 || (N) == 35)
#define ACCESS_REGNO_P(N)	((N) == 36 || (N) == 37)

#define GENERAL_REG_P(X)	(REG_P (X) && GENERAL_REGNO_P (REGNO (X)))
#define ADDR_REG_P(X)		(REG_P (X) && ADDR_REGNO_P (REGNO (X)))
#define FP_REG_P(X)		(REG_P (X) && FP_REGNO_P (REGNO (X)))
#define CC_REG_P(X)		(REG_P (X) && CC_REGNO_P (REGNO (X)))
#define FRAME_REG_P(X)		(REG_P (X) && FRAME_REGNO_P (REGNO (X)))
#define ACCESS_REG_P(X)		(REG_P (X) && ACCESS_REGNO_P (REGNO (X)))

/* Set up fixed registers and calling convention:

   GPRs 0-5 are always call-clobbered,
   GPRs 6-15 are always call-saved.
   GPR 12 is fixed if used as GOT pointer.
   GPR 13 is always fixed (as literal pool pointer).
   GPR 14 is always fixed on S/390 machines (as return address).
   GPR 15 is always fixed (as stack pointer).
   The 'fake' hard registers are call-clobbered and fixed.
   The access registers are call-saved and fixed.

   On 31-bit, FPRs 18-19 are call-clobbered;
   on 64-bit, FPRs 24-31 are call-clobbered.
   The remaining FPRs are call-saved.  */

#define FIXED_REGISTERS				\
{ 0, 0, 0, 0, 					\
  0, 0, 0, 0, 					\
  0, 0, 0, 0, 					\
  0, 1, 1, 1,					\
  0, 0, 0, 0, 					\
  0, 0, 0, 0, 					\
  0, 0, 0, 0, 					\
  0, 0, 0, 0, 					\
  1, 1, 1, 1,					\
  1, 1 }

#define CALL_USED_REGISTERS			\
{ 1, 1, 1, 1, 					\
  1, 1, 0, 0, 					\
  0, 0, 0, 0, 					\
  0, 1, 1, 1,					\
  1, 1, 1, 1, 					\
  1, 1, 1, 1, 					\
  1, 1, 1, 1, 					\
  1, 1, 1, 1, 					\
  1, 1, 1, 1,					\
  1, 1 }

#define CALL_REALLY_USED_REGISTERS		\
{ 1, 1, 1, 1, 					\
  1, 1, 0, 0, 					\
  0, 0, 0, 0, 					\
  0, 0, 0, 0,					\
  1, 1, 1, 1, 					\
  1, 1, 1, 1, 					\
  1, 1, 1, 1, 					\
  1, 1, 1, 1, 					\
  1, 1, 1, 1,					\
  0, 0 }

#define CONDITIONAL_REGISTER_USAGE s390_conditional_register_usage ()

/* Preferred register allocation order.  */
#define REG_ALLOC_ORDER                                         \
{  1, 2, 3, 4, 5, 0, 12, 11, 10, 9, 8, 7, 6, 14, 13,            \
   16, 17, 18, 19, 20, 21, 22, 23,                              \
   24, 25, 26, 27, 28, 29, 30, 31,                              \
   15, 32, 33, 34, 35, 36, 37 }


/* Fitting values into registers.  */

/* Integer modes <= word size fit into any GPR.
   Integer modes > word size fit into successive GPRs, starting with
   an even-numbered register.
   SImode and DImode fit into FPRs as well.

   Floating point modes <= word size fit into any FPR or GPR.
   Floating point modes > word size (i.e. DFmode on 32-bit) fit
   into any FPR, or an even-odd GPR pair.
   TFmode fits only into an even-odd FPR pair.

   Complex floating point modes fit either into two FPRs, or into
   successive GPRs (again starting with an even number).
   TCmode fits only into two successive even-odd FPR pairs.

   Condition code modes fit only into the CC register.  */

/* Because all registers in a class have the same size HARD_REGNO_NREGS
   is equivalent to CLASS_MAX_NREGS.  */
#define HARD_REGNO_NREGS(REGNO, MODE)                           \
  s390_class_max_nregs (REGNO_REG_CLASS (REGNO), (MODE))

#define HARD_REGNO_MODE_OK(REGNO, MODE)         \
  s390_hard_regno_mode_ok ((REGNO), (MODE))

#define HARD_REGNO_RENAME_OK(FROM, TO)          \
  s390_hard_regno_rename_ok (FROM, TO)

#define MODES_TIEABLE_P(MODE1, MODE2)		\
   (((MODE1) == SFmode || (MODE1) == DFmode)	\
   == ((MODE2) == SFmode || (MODE2) == DFmode))

/* When generating code that runs in z/Architecture mode,
   but conforms to the 31-bit ABI, GPRs can hold 8 bytes;
   the ABI guarantees only that the lower 4 bytes are
   saved across calls, however.  */
#define HARD_REGNO_CALL_PART_CLOBBERED(REGNO, MODE)		\
  (!TARGET_64BIT && TARGET_ZARCH				\
   && GET_MODE_SIZE (MODE) > 4					\
   && (((REGNO) >= 6 && (REGNO) <= 15) || (REGNO) == 32))

/* Maximum number of registers to represent a value of mode MODE
   in a register of class CLASS.  */
#define CLASS_MAX_NREGS(CLASS, MODE)   					\
  s390_class_max_nregs ((CLASS), (MODE))

/* If a 4-byte value is loaded into a FPR, it is placed into the
   *upper* half of the register, not the lower.  Therefore, we
   cannot use SUBREGs to switch between modes in FP registers.
   Likewise for access registers, since they have only half the
   word size on 64-bit.  */
#define CANNOT_CHANGE_MODE_CLASS(FROM, TO, CLASS)		        \
  (GET_MODE_SIZE (FROM) != GET_MODE_SIZE (TO)			        \
   ? ((reg_classes_intersect_p (FP_REGS, CLASS)				\
       && (GET_MODE_SIZE (FROM) < 8 || GET_MODE_SIZE (TO) < 8))		\
      || reg_classes_intersect_p (ACCESS_REGS, CLASS)) : 0)

/* Register classes.  */

/* We use the following register classes:
   GENERAL_REGS     All general purpose registers
   ADDR_REGS        All general purpose registers except %r0
                    (These registers can be used in address generation)
   FP_REGS          All floating point registers
   CC_REGS          The condition code register
   ACCESS_REGS      The access registers

   GENERAL_FP_REGS  Union of GENERAL_REGS and FP_REGS
   ADDR_FP_REGS     Union of ADDR_REGS and FP_REGS
   GENERAL_CC_REGS  Union of GENERAL_REGS and CC_REGS
   ADDR_CC_REGS     Union of ADDR_REGS and CC_REGS

   NO_REGS          No registers
   ALL_REGS         All registers

   Note that the 'fake' frame pointer and argument pointer registers
   are included amongst the address registers here.  */

enum reg_class
{
  NO_REGS, CC_REGS, ADDR_REGS, GENERAL_REGS, ACCESS_REGS,
  ADDR_CC_REGS, GENERAL_CC_REGS,
  FP_REGS, ADDR_FP_REGS, GENERAL_FP_REGS,
  ALL_REGS, LIM_REG_CLASSES
};
#define N_REG_CLASSES (int) LIM_REG_CLASSES

#define REG_CLASS_NAMES							\
{ "NO_REGS", "CC_REGS", "ADDR_REGS", "GENERAL_REGS", "ACCESS_REGS",	\
  "ADDR_CC_REGS", "GENERAL_CC_REGS",					\
  "FP_REGS", "ADDR_FP_REGS", "GENERAL_FP_REGS", "ALL_REGS" }

/* Class -> register mapping.  */
#define REG_CLASS_CONTENTS \
{				       			\
  { 0x00000000, 0x00000000 },	/* NO_REGS */		\
  { 0x00000000, 0x00000002 },	/* CC_REGS */		\
  { 0x0000fffe, 0x0000000d },	/* ADDR_REGS */		\
  { 0x0000ffff, 0x0000000d },	/* GENERAL_REGS */	\
  { 0x00000000, 0x00000030 },	/* ACCESS_REGS */	\
  { 0x0000fffe, 0x0000000f },	/* ADDR_CC_REGS */	\
  { 0x0000ffff, 0x0000000f },	/* GENERAL_CC_REGS */	\
  { 0xffff0000, 0x00000000 },	/* FP_REGS */		\
  { 0xfffffffe, 0x0000000d },	/* ADDR_FP_REGS */	\
  { 0xffffffff, 0x0000000d },	/* GENERAL_FP_REGS */	\
  { 0xffffffff, 0x0000003f },	/* ALL_REGS */		\
}

/* The following macro defines cover classes for Integrated Register
   Allocator.  Cover classes is a set of non-intersected register
   classes covering all hard registers used for register allocation
   purpose.  Any move between two registers of a cover class should be
   cheaper than load or store of the registers.  The macro value is
   array of register classes with LIM_REG_CLASSES used as the end
   marker.  */

#define IRA_COVER_CLASSES						     \
{									     \
  GENERAL_REGS, FP_REGS, CC_REGS, ACCESS_REGS, LIM_REG_CLASSES		     \
}

/* In some case register allocation order is not enough for IRA to
   generate a good code.  The following macro (if defined) increases
   cost of REGNO for a pseudo approximately by pseudo usage frequency
   multiplied by the macro value.

   We avoid usage of BASE_REGNUM by nonzero macro value because the
   reload can decide not to use the hard register because some
   constant was forced to be in memory.  */
#define IRA_HARD_REGNO_ADD_COST_MULTIPLIER(regno)	\
  (regno == BASE_REGNUM ? 0.0 : 0.5)

/* Register -> class mapping.  */
extern const enum reg_class regclass_map[FIRST_PSEUDO_REGISTER];
#define REGNO_REG_CLASS(REGNO) (regclass_map[REGNO])

/* ADDR_REGS can be used as base or index register.  */
#define INDEX_REG_CLASS ADDR_REGS
#define BASE_REG_CLASS ADDR_REGS

/* Check whether REGNO is a hard register of the suitable class
   or a pseudo register currently allocated to one such.  */
#define REGNO_OK_FOR_INDEX_P(REGNO)					\
    (((REGNO) < FIRST_PSEUDO_REGISTER 					\
      && REGNO_REG_CLASS ((REGNO)) == ADDR_REGS) 			\
     || ADDR_REGNO_P (reg_renumber[REGNO]))
#define REGNO_OK_FOR_BASE_P(REGNO) REGNO_OK_FOR_INDEX_P (REGNO)


/* Given an rtx X being reloaded into a reg required to be in class CLASS,
   return the class of reg to actually use.  */
#define PREFERRED_RELOAD_CLASS(X, CLASS)	\
  s390_preferred_reload_class ((X), (CLASS))

/* We need secondary memory to move data between GPRs and FPRs.  With
   DFP the ldgr lgdr instructions are available.  But these
   instructions do not handle GPR pairs so it is not possible for 31
   bit.  */
#define SECONDARY_MEMORY_NEEDED(CLASS1, CLASS2, MODE) \
 ((CLASS1) != (CLASS2)                                \
  && ((CLASS1) == FP_REGS || (CLASS2) == FP_REGS)     \
  && (!TARGET_DFP || !TARGET_64BIT || GET_MODE_SIZE (MODE) != 8))

/* Get_secondary_mem widens its argument to BITS_PER_WORD which loses on 64bit
   because the movsi and movsf patterns don't handle r/f moves.  */
#define SECONDARY_MEMORY_NEEDED_MODE(MODE)		\
 (GET_MODE_BITSIZE (MODE) < 32				\
  ? mode_for_size (32, GET_MODE_CLASS (MODE), 0)	\
  : MODE)


/* Stack layout and calling conventions.  */

/* Our stack grows from higher to lower addresses.  However, local variables
   are accessed by positive offsets, and function arguments are stored at
   increasing addresses.  */
#define STACK_GROWS_DOWNWARD
#define FRAME_GROWS_DOWNWARD 1
/* #undef ARGS_GROW_DOWNWARD */

/* The basic stack layout looks like this: the stack pointer points
   to the register save area for called functions.  Above that area
   is the location to place outgoing arguments.  Above those follow
   dynamic allocations (alloca), and finally the local variables.  */

/* Offset from stack-pointer to first location of outgoing args.  */
#define STACK_POINTER_OFFSET (TARGET_64BIT ? 160 : 96)

/* Offset within stack frame to start allocating local variables at.  */
#define STARTING_FRAME_OFFSET 0

/* Offset from the stack pointer register to an item dynamically
   allocated on the stack, e.g., by `alloca'.  */
#define STACK_DYNAMIC_OFFSET(FUNDECL) \
  (STACK_POINTER_OFFSET + crtl->outgoing_args_size)

/* Offset of first parameter from the argument pointer register value.
   We have a fake argument pointer register that points directly to
   the argument area.  */
#define FIRST_PARM_OFFSET(FNDECL) 0

/* Defining this macro makes __builtin_frame_address(0) and
   __builtin_return_address(0) work with -fomit-frame-pointer.  */
#define INITIAL_FRAME_ADDRESS_RTX                                             \
  (plus_constant (arg_pointer_rtx, -STACK_POINTER_OFFSET))

/* The return address of the current frame is retrieved
   from the initial value of register RETURN_REGNUM.
   For frames farther back, we use the stack slot where
   the corresponding RETURN_REGNUM register was saved.  */
#define DYNAMIC_CHAIN_ADDRESS(FRAME)                                          \
  (TARGET_PACKED_STACK ?                                                      \
   plus_constant ((FRAME), STACK_POINTER_OFFSET - UNITS_PER_LONG) : (FRAME))

/* For -mpacked-stack this adds 160 - 8 (96 - 4) to the output of
   builtin_frame_address.  Otherwise arg pointer -
   STACK_POINTER_OFFSET would be returned for
   __builtin_frame_address(0) what might result in an address pointing
   somewhere into the middle of the local variables since the packed
   stack layout generally does not need all the bytes in the register
   save area.  */
#define FRAME_ADDR_RTX(FRAME)			\
  DYNAMIC_CHAIN_ADDRESS ((FRAME))

#define RETURN_ADDR_RTX(COUNT, FRAME)					      \
  s390_return_addr_rtx ((COUNT), DYNAMIC_CHAIN_ADDRESS ((FRAME)))

/* In 31-bit mode, we need to mask off the high bit of return addresses.  */
#define MASK_RETURN_ADDR (TARGET_64BIT ? constm1_rtx : GEN_INT (0x7fffffff))


/* Exception handling.  */

/* Describe calling conventions for DWARF-2 exception handling.  */
#define INCOMING_RETURN_ADDR_RTX  gen_rtx_REG (Pmode, RETURN_REGNUM)
#define INCOMING_FRAME_SP_OFFSET STACK_POINTER_OFFSET
#define DWARF_FRAME_RETURN_COLUMN  14

/* Describe how we implement __builtin_eh_return.  */
#define EH_RETURN_DATA_REGNO(N) ((N) < 4 ? (N) + 6 : INVALID_REGNUM)
#define EH_RETURN_HANDLER_RTX gen_rtx_MEM (Pmode, return_address_pointer_rtx)

/* Select a format to encode pointers in exception handling data.  */
#define ASM_PREFERRED_EH_DATA_FORMAT(CODE, GLOBAL)			    \
  (flag_pic								    \
    ? ((GLOBAL) ? DW_EH_PE_indirect : 0) | DW_EH_PE_pcrel | DW_EH_PE_sdata4 \
   : DW_EH_PE_absptr)

/* Register save slot alignment.  */
#define DWARF_CIE_DATA_ALIGNMENT (-UNITS_PER_LONG)


/* Frame registers.  */

#define STACK_POINTER_REGNUM 15
#define FRAME_POINTER_REGNUM 34
#define HARD_FRAME_POINTER_REGNUM 11
#define ARG_POINTER_REGNUM 32
#define RETURN_ADDRESS_POINTER_REGNUM 35

/* The static chain must be call-clobbered, but not used for
   function argument passing.  As register 1 is clobbered by
   the trampoline code, we only have one option.  */
#define STATIC_CHAIN_REGNUM 0

/* Number of hardware registers that go into the DWARF-2 unwind info.
   To avoid ABI incompatibility, this number must not change even as
   'fake' hard registers are added or removed.  */
#define DWARF_FRAME_REGISTERS 34


/* Frame pointer and argument pointer elimination.  */

#define ELIMINABLE_REGS						\
{{ FRAME_POINTER_REGNUM, STACK_POINTER_REGNUM },		\
 { FRAME_POINTER_REGNUM, HARD_FRAME_POINTER_REGNUM },		\
 { ARG_POINTER_REGNUM, STACK_POINTER_REGNUM },			\
 { ARG_POINTER_REGNUM, HARD_FRAME_POINTER_REGNUM },		\
 { RETURN_ADDRESS_POINTER_REGNUM, STACK_POINTER_REGNUM },	\
 { RETURN_ADDRESS_POINTER_REGNUM, HARD_FRAME_POINTER_REGNUM },	\
 { BASE_REGNUM, BASE_REGNUM }}

#define INITIAL_ELIMINATION_OFFSET(FROM, TO, OFFSET) \
  (OFFSET) = s390_initial_elimination_offset ((FROM), (TO))


/* Stack arguments.  */

/* We need current_function_outgoing_args to be valid.  */
#define ACCUMULATE_OUTGOING_ARGS 1


/* Register arguments.  */

typedef struct s390_arg_structure
{
  int gprs;			/* gpr so far */
  int fprs;			/* fpr so far */
}
CUMULATIVE_ARGS;

#define INIT_CUMULATIVE_ARGS(CUM, FNTYPE, LIBNAME, NN, N_NAMED_ARGS) \
  ((CUM).gprs=0, (CUM).fprs=0)

#define FUNCTION_ARG_ADVANCE(CUM, MODE, TYPE, NAMED)                    \
  s390_function_arg_advance (&CUM, MODE, TYPE, NAMED)

#define FUNCTION_ARG(CUM, MODE, TYPE, NAMED)   \
  s390_function_arg (&CUM, MODE, TYPE, NAMED)

/* Arguments can be placed in general registers 2 to 6, or in floating
   point registers 0 and 2 for 31 bit and fprs 0, 2, 4 and 6 for 64
   bit.  */
#define FUNCTION_ARG_REGNO_P(N) (((N) >=2 && (N) <7) || \
  (N) == 16 || (N) == 17 || (TARGET_64BIT && ((N) == 18 || (N) == 19)))


/* Scalar return values.  */

#define FUNCTION_VALUE(VALTYPE, FUNC) \
  s390_function_value ((VALTYPE), (FUNC), VOIDmode)

#define LIBCALL_VALUE(MODE) \
  s390_function_value (NULL, NULL, (MODE))

/* Only gpr 2 and fpr 0 are ever used as return registers.  */
#define FUNCTION_VALUE_REGNO_P(N) ((N) == 2 || (N) == 16)


/* Function entry and exit.  */

/* When returning from a function, the stack pointer does not matter.  */
#define EXIT_IGNORE_STACK       1


/* Profiling.  */

#define FUNCTION_PROFILER(FILE, LABELNO) 			\
  s390_function_profiler ((FILE), ((LABELNO)))

#define PROFILE_BEFORE_PROLOGUE 1


/* Trampolines for nested functions.  */

#define TRAMPOLINE_SIZE		(TARGET_64BIT ? 32 : 16)
#define TRAMPOLINE_ALIGNMENT	BITS_PER_WORD

/* Addressing modes, and classification of registers for them.  */

/* Recognize any constant value that is a valid address.  */
#define CONSTANT_ADDRESS_P(X) 0

/* Maximum number of registers that can appear in a valid memory address.  */
#define MAX_REGS_PER_ADDRESS 2

/* This definition replaces the formerly used 'm' constraint with a
   different constraint letter in order to avoid changing semantics of
   the 'm' constraint when accepting new address formats in
   TARGET_LEGITIMATE_ADDRESS_P.  The constraint letter defined here
   must not be used in insn definitions or inline assemblies.  */
#define TARGET_MEM_CONSTRAINT 'e'

/* Try a machine-dependent way of reloading an illegitimate address
   operand.  If we find one, push the reload and jump to WIN.  This
   macro is used in only one place: `find_reloads_address' in reload.c.  */
#define LEGITIMIZE_RELOAD_ADDRESS(AD, MODE, OPNUM, TYPE, IND, WIN)	\
do {									\
  rtx new_rtx = legitimize_reload_address (AD, MODE, OPNUM, (int)(TYPE));	\
  if (new_rtx)								\
    {									\
      (AD) = new_rtx;							\
      goto WIN;								\
    }									\
} while (0)

/* Nonzero if the constant value X is a legitimate general operand.
   It is given that X satisfies CONSTANT_P or is a CONST_DOUBLE.  */
#define LEGITIMATE_CONSTANT_P(X) \
     legitimate_constant_p (X)

/* Helper macro for s390.c and s390.md to check for symbolic constants.  */
#define SYMBOLIC_CONST(X)       \
(GET_CODE (X) == SYMBOL_REF                                             \
 || GET_CODE (X) == LABEL_REF                                           \
 || (GET_CODE (X) == CONST && symbolic_reference_mentioned_p (X)))

#define TLS_SYMBOLIC_CONST(X)	\
((GET_CODE (X) == SYMBOL_REF && tls_symbolic_operand (X))	\
 || (GET_CODE (X) == CONST && tls_symbolic_reference_mentioned_p (X)))


/* Condition codes.  */

/* Given a comparison code (EQ, NE, etc.) and the first operand of a COMPARE,
   return the mode to be used for the comparison.  */
#define SELECT_CC_MODE(OP, X, Y) s390_select_ccmode ((OP), (X), (Y))

/* Canonicalize a comparison from one we don't have to one we do have.  */
#define CANONICALIZE_COMPARISON(CODE, OP0, OP1) \
  s390_canonicalize_comparison (&(CODE), &(OP0), &(OP1))

/* Relative costs of operations.  */

/* On s390, copy between fprs and gprs is expensive.  */
#define REGISTER_MOVE_COST(MODE, CLASS1, CLASS2)                        \
  ((   (   reg_classes_intersect_p ((CLASS1), GENERAL_REGS)		\
        && reg_classes_intersect_p ((CLASS2), FP_REGS))			\
    || (   reg_classes_intersect_p ((CLASS1), FP_REGS)			\
        && reg_classes_intersect_p ((CLASS2), GENERAL_REGS))) ? 10 : 1)

/* A C expression for the cost of moving data of mode M between a
   register and memory.  A value of 2 is the default; this cost is
   relative to those in `REGISTER_MOVE_COST'.  */
#define MEMORY_MOVE_COST(M, C, I) 1

/* A C expression for the cost of a branch instruction.  A value of 1
   is the default; other values are interpreted relative to that.  */
#define BRANCH_COST(speed_p, predictable_p) 1

/* Nonzero if access to memory by bytes is slow and undesirable.  */
#define SLOW_BYTE_ACCESS 1

/* An integer expression for the size in bits of the largest integer machine
   mode that should actually be used.  We allow pairs of registers.  */
#define MAX_FIXED_MODE_SIZE GET_MODE_BITSIZE (TARGET_64BIT ? TImode : DImode)

/* The maximum number of bytes that a single instruction can move quickly
   between memory and registers or between two memory locations.  */
#define MOVE_MAX (TARGET_ZARCH ? 16 : 8)
#define MOVE_MAX_PIECES (TARGET_ZARCH ? 8 : 4)
#define MAX_MOVE_MAX 16

/* Determine whether to use move_by_pieces or block move insn.  */
#define MOVE_BY_PIECES_P(SIZE, ALIGN)		\
  ( (SIZE) == 1 || (SIZE) == 2 || (SIZE) == 4	\
    || (TARGET_ZARCH && (SIZE) == 8) )

/* Determine whether to use clear_by_pieces or block clear insn.  */
#define CLEAR_BY_PIECES_P(SIZE, ALIGN)		\
  ( (SIZE) == 1 || (SIZE) == 2 || (SIZE) == 4	\
    || (TARGET_ZARCH && (SIZE) == 8) )

/* This macro is used to determine whether store_by_pieces should be
   called to "memcpy" storage when the source is a constant string.  */
#define STORE_BY_PIECES_P(SIZE, ALIGN) MOVE_BY_PIECES_P (SIZE, ALIGN)

/* Likewise to decide whether to "memset" storage with byte values
   other than zero.  */
#define SET_BY_PIECES_P(SIZE, ALIGN) STORE_BY_PIECES_P (SIZE, ALIGN)

/* Don't perform CSE on function addresses.  */
#define NO_FUNCTION_CSE

/* This value is used in tree-sra to decide whether it might benefical
   to split a struct move into several word-size moves.  For S/390
   only small values make sense here since struct moves are relatively
   cheap thanks to mvc so the small default value choosen for archs
   with memmove patterns should be ok.  But this value is multiplied
   in tree-sra with UNITS_PER_WORD to make a decision so we adjust it
   here to compensate for that factor since mvc costs exactly the same
   on 31 and 64 bit.  */
#define MOVE_RATIO(speed) (TARGET_64BIT? 2 : 4)


/* Sections.  */

/* Output before read-only data.  */
#define TEXT_SECTION_ASM_OP ".text"

/* Output before writable (initialized) data.  */
#define DATA_SECTION_ASM_OP ".data"

/* Output before writable (uninitialized) data.  */
#define BSS_SECTION_ASM_OP ".bss"

/* S/390 constant pool breaks the devices in crtstuff.c to control section
   in where code resides.  We have to write it as asm code.  */
#ifndef __s390x__
#define CRT_CALL_STATIC_FUNCTION(SECTION_OP, FUNC) \
    asm (SECTION_OP "\n\
	bras\t%r2,1f\n\
0:	.long\t" USER_LABEL_PREFIX #FUNC " - 0b\n\
1:	l\t%r3,0(%r2)\n\
	bas\t%r14,0(%r3,%r2)\n\
	.previous");
#endif


/* Position independent code.  */

#define PIC_OFFSET_TABLE_REGNUM (flag_pic ? 12 : INVALID_REGNUM)

#define LEGITIMATE_PIC_OPERAND_P(X)  legitimate_pic_operand_p (X)


/* Assembler file format.  */

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

/* Declare an uninitialized external linkage data object.  */
#define ASM_OUTPUT_ALIGNED_BSS(FILE, DECL, NAME, SIZE, ALIGN) \
  asm_output_aligned_bss (FILE, DECL, NAME, SIZE, ALIGN)

/* Globalizing directive for a label.  */
#define GLOBAL_ASM_OP ".globl "

/* Advance the location counter to a multiple of 2**LOG bytes.  */
#define ASM_OUTPUT_ALIGN(FILE, LOG) \
  if ((LOG)) fprintf ((FILE), "\t.align\t%d\n", 1 << (LOG))

/* Advance the location counter by SIZE bytes.  */
#define ASM_OUTPUT_SKIP(FILE, SIZE) \
  fprintf ((FILE), "\t.set\t.,.+"HOST_WIDE_INT_PRINT_UNSIGNED"\n", (SIZE))

/* The LOCAL_LABEL_PREFIX variable is used by dbxelf.h.  */
#define LOCAL_LABEL_PREFIX "."

/* How to refer to registers in assembler output.  This sequence is
   indexed by compiler's hard-register-number (see above).  */
#define REGISTER_NAMES							\
{ "%r0",  "%r1",  "%r2",  "%r3",  "%r4",  "%r5",  "%r6",  "%r7",	\
  "%r8",  "%r9",  "%r10", "%r11", "%r12", "%r13", "%r14", "%r15",	\
  "%f0",  "%f2",  "%f4",  "%f6",  "%f1",  "%f3",  "%f5",  "%f7",	\
  "%f8",  "%f10", "%f12", "%f14", "%f9",  "%f11", "%f13", "%f15",	\
  "%ap",  "%cc",  "%fp",  "%rp",  "%a0",  "%a1"				\
}

/* Print operand X (an rtx) in assembler syntax to file FILE.  */
#define PRINT_OPERAND(FILE, X, CODE) print_operand (FILE, X, CODE)
#define PRINT_OPERAND_ADDRESS(FILE, ADDR) print_operand_address (FILE, ADDR)

/* Output machine-dependent UNSPECs in address constants.  */
#define OUTPUT_ADDR_CONST_EXTRA(FILE, X, FAIL)		\
do {							\
  if (!s390_output_addr_const_extra (FILE, (X)))	\
    goto FAIL;						\
} while (0);

/* Output an element of a case-vector that is absolute.  */
#define ASM_OUTPUT_ADDR_VEC_ELT(FILE, VALUE)				\
do {									\
  char buf[32];								\
  fputs (integer_asm_op (UNITS_PER_LONG, TRUE), (FILE));		\
  ASM_GENERATE_INTERNAL_LABEL (buf, "L", (VALUE));			\
  assemble_name ((FILE), buf);						\
  fputc ('\n', (FILE));							\
} while (0)

/* Output an element of a case-vector that is relative.  */
#define ASM_OUTPUT_ADDR_DIFF_ELT(FILE, BODY, VALUE, REL)		\
do {									\
  char buf[32];								\
  fputs (integer_asm_op (UNITS_PER_LONG, TRUE), (FILE));		\
  ASM_GENERATE_INTERNAL_LABEL (buf, "L", (VALUE));			\
  assemble_name ((FILE), buf);						\
  fputc ('-', (FILE));							\
  ASM_GENERATE_INTERNAL_LABEL (buf, "L", (REL));			\
  assemble_name ((FILE), buf);						\
  fputc ('\n', (FILE));							\
} while (0)


/* Miscellaneous parameters.  */

/* Specify the machine mode that this machine uses for the index in the
   tablejump instruction.  */
#define CASE_VECTOR_MODE (TARGET_64BIT ? DImode : SImode)

/* Value is 1 if truncating an integer of INPREC bits to OUTPREC bits
   is done just by pretending it is already truncated.  */
#define TRULY_NOOP_TRUNCATION(OUTPREC, INPREC)  1

/* Specify the machine mode that pointers have.
   After generation of rtl, the compiler makes no further distinction
   between pointers and any other objects of this machine mode.  */
#define Pmode ((enum machine_mode) (TARGET_64BIT ? DImode : SImode))

/* This is -1 for "pointer mode" extend.  See ptr_extend in s390.md.  */
#define POINTERS_EXTEND_UNSIGNED -1

/* A function address in a call instruction is a byte address (for
   indexing purposes) so give the MEM rtx a byte's mode.  */
#define FUNCTION_MODE QImode

/* Specify the value which is used when clz operand is zero.  */
#define CLZ_DEFINED_VALUE_AT_ZERO(MODE, VALUE) ((VALUE) = 64, 1)

/* Machine-specific symbol_ref flags.  */
#define SYMBOL_FLAG_ALIGN1	          (SYMBOL_FLAG_MACH_DEP << 0)
#define SYMBOL_REF_ALIGN1_P(X)		\
  ((SYMBOL_REF_FLAGS (X) & SYMBOL_FLAG_ALIGN1))
#define SYMBOL_FLAG_NOT_NATURALLY_ALIGNED (SYMBOL_FLAG_MACH_DEP << 1)
#define SYMBOL_REF_NOT_NATURALLY_ALIGNED_P(X) \
  ((SYMBOL_REF_FLAGS (X) & SYMBOL_FLAG_NOT_NATURALLY_ALIGNED))

/* Check whether integer displacement is in range.  */
#define DISP_IN_RANGE(d) \
  (TARGET_LONG_DISPLACEMENT? ((d) >= -524288 && (d) <= 524287) \
                           : ((d) >= 0 && (d) <= 4095))

/* Reads can reuse write prefetches, used by tree-ssa-prefetch-loops.c.  */
#define READ_CAN_USE_WRITE_PREFETCH 1
#endif