include/toolchain/common.h

/* toolchain/common.h - common toolchain abstraction */

/*
 * Copyright (c) 2010-2014 Wind River Systems, Inc.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1) Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 *
 * 2) Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * 3) Neither the name of Wind River Systems nor the names of its contributors
 * may be used to endorse or promote products derived from this software without
 * specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

/*
DESCRIPTION
Macros to abstract compiler capabilities (common to all toolchains).

\NOMANUAL
 */

/*
 * Generate a reference to an external symbol.
 * The reference indicates to the linker that the symbol is required
 * by the module containing the reference and should be included
 * in the image if the module is in the image.
 *
 * The assembler directive ".set" is used to define a local symbol.
 * No memory is allocated, and the local symbol does not appear in
 * the symbol table.
 */

#ifdef _ASMLANGUAGE
  #define REQUIRES(sym) .set sym ## _Requires, sym
#else
  #define REQUIRES(sym) __asm__ (".set " # sym "_Requires, " # sym "\n\t");
#endif

#ifdef _ASMLANGUAGE
  #define SECTION .section
#endif

/*
 * The following definitions are used for symbol name compatibility.
 *
 * When #if 1, sources are assembled assuming the compiler
 * you are using does not generate global symbols prefixed by "_".
 * (e.g. elf/dwarf)
 *
 * When #if 0, sources are assembled assuming the compiler
 * you are using generates global symbols prefixed by "_".
 * (e.g. coff/stabs)
 */

#ifdef _ASMLANGUAGE
  #ifndef TOOL_PREPENDS_UNDERSCORE
    #define FUNC(sym) sym
  #else
    #define FUNC(sym) _##sym
  #endif
#endif

/*
 * If the project is being built for speed (i.e. not for minimum size) then
 * align functions and branches in executable sections to improve performance.
 */

#ifdef _ASMLANGUAGE

  #ifdef CONFIG_X86_32

    #ifdef PERF_OPT
      #define PERFOPT_ALIGN .balign 16
    #else
      #define PERFOPT_ALIGN .balign  1
    #endif

  #elif defined(CONFIG_ARM)

    #ifdef CONFIG_ISA_THUMB
      #define PERFOPT_ALIGN .balign  2
    #else
      #define PERFOPT_ALIGN .balign  4
    #endif

  #elif defined(CONFIG_ARC)

    #define PERFOPT_ALIGN .balign  4

  #endif

  #define GC_SECTION(sym) SECTION .text.FUNC(sym), "ax"

  #define BRANCH_LABEL(sym) FUNC(sym):
  #define VAR(sym)          FUNC(sym)

#endif /* _ASMLANGUAGE */

/* force inlining a function */

#if !defined(_ASMLANGUAGE)
  #define ALWAYS_INLINE inline __attribute__((always_inline))
#endif

#define _STRINGIFY(x) #x

/* Indicate that an array will be used for stack space. */

#define __stack __aligned(STACK_ALIGN)

#ifdef CONFIG_UNALIGNED_WRITE_UNSUPPORTED
extern void     _Unaligned32Write(unsigned int *ptr, unsigned int val);
extern unsigned _Unaligned32Read(unsigned int *ptr);
#endif /* CONFIG_UNALIGNED_WRITE_UNSUPPORTED */