1/* NetBSD/arm a.out version. 2 Copyright (C) 1993, 1994, 1997, 1998, 2003, 2004, 2005 3 Free Software Foundation, Inc. 4 Contributed by Mark Brinicombe (amb@physig.ph.kcl.ac.uk) 5 6 This file is part of GCC. 7 8 GCC is free software; you can redistribute it and/or modify it 9 under the terms of the GNU General Public License as published 10 by the Free Software Foundation; either version 2, or (at your 11 option) any later version. 12 13 GCC is distributed in the hope that it will be useful, but WITHOUT 14 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 15 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public 16 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 COPYING. If not, write to 20 the Free Software Foundation, 51 Franklin Street, Fifth Floor, 21 Boston, MA 02110-1301, USA. */ 22 23/* Run-time Target Specification. */ 24#undef TARGET_VERSION 25#define TARGET_VERSION fputs (" (ARM/NetBSD)", stderr); 26 27/* Unsigned chars produces much better code than signed. */ 28#define DEFAULT_SIGNED_CHAR 0 29 30/* Since we always use GAS as our assembler we support stabs. */ 31#define DBX_DEBUGGING_INFO 1 32 33/*#undef ASM_DECLARE_FUNCTION_NAME*/ 34 35/* ARM6 family default cpu. */ 36#define SUBTARGET_CPU_DEFAULT TARGET_CPU_arm6 37 38#undef TARGET_DEFAULT 39#define TARGET_DEFAULT (MASK_APCS_FRAME) 40 41/* Some defines for CPP. 42 arm32 is the NetBSD port name, so we always define arm32 and __arm32__. */ 43#define TARGET_OS_CPP_BUILTINS() \ 44 do { \ 45 NETBSD_OS_CPP_BUILTINS_AOUT(); \ 46 builtin_define_std ("arm32"); \ 47 builtin_define_std ("unix"); \ 48 builtin_define_std ("riscbsd"); \ 49 } while (0) 50 51#undef SUBTARGET_EXTRA_SPECS 52#define SUBTARGET_EXTRA_SPECS \ 53 { "netbsd_cpp_spec", NETBSD_CPP_SPEC }, \ 54 { "netbsd_link_spec", NETBSD_LINK_SPEC_AOUT }, 55 56#undef CPP_SPEC 57#define CPP_SPEC "\ 58%(cpp_cpu_arch) %(cpp_float) %(cpp_endian) %(netbsd_cpp_spec) \ 59" 60 61/* Because TARGET_DEFAULT sets MASK_SOFT_FLOAT */ 62#undef CPP_FLOAT_DEFAULT_SPEC 63#define CPP_FLOAT_DEFAULT_SPEC "-D__SOFTFP__" 64 65/* Pass -X to the linker so that it will strip symbols starting with 'L' */ 66#undef LINK_SPEC 67#define LINK_SPEC "-X %(netbsd_link_spec)" 68 69#undef SIZE_TYPE 70#define SIZE_TYPE "unsigned int" 71 72#undef PTRDIFF_TYPE 73#define PTRDIFF_TYPE "int" 74 75#define HANDLE_SYSV_PRAGMA 1 76 77/* We don't have any limit on the length as out debugger is GDB. */ 78#undef DBX_CONTIN_LENGTH 79 80/* NetBSD does its profiling differently to the Acorn compiler. We 81 don't need a word following the mcount call; and to skip it 82 requires either an assembly stub or use of fomit-frame-pointer when 83 compiling the profiling functions. Since we break Acorn CC 84 compatibility below a little more won't hurt. */ 85 86#undef ARM_FUNCTION_PROFILER 87#define ARM_FUNCTION_PROFILER(STREAM,LABELNO) \ 88{ \ 89 fprintf(STREAM, "\tmov\t%sip, %slr\n", REGISTER_PREFIX, REGISTER_PREFIX); \ 90 fprintf(STREAM, "\tbl\tmcount\n"); \ 91} 92 93/* On the ARM `@' introduces a comment, so we must use something else 94 for .type directives. */ 95#undef TYPE_OPERAND_FMT 96#define TYPE_OPERAND_FMT "%%%s" 97 98/* NetBSD uses the old PCC style aggregate returning conventions. */ 99#undef DEFAULT_PCC_STRUCT_RETURN 100#define DEFAULT_PCC_STRUCT_RETURN 1 101 102/* Although not normally relevant (since by default, all aggregates 103 are returned in memory) compiling some parts of libc requires 104 non-APCS style struct returns. */ 105#undef RETURN_IN_MEMORY 106 107/* VERY BIG NOTE : Change of structure alignment for RiscBSD. 108 There are consequences you should be aware of... 109 110 Normally GCC/arm uses a structure alignment of 32 for compatibility 111 with armcc. This means that structures are padded to a word 112 boundary. However this causes problems with bugged NetBSD kernel 113 code (possibly userland code as well - I have not checked every 114 binary). The nature of this bugged code is to rely on sizeof() 115 returning the correct size of various structures rounded to the 116 nearest byte (SCSI and ether code are two examples, the vm system 117 is another). This code breaks when the structure alignment is 32 118 as sizeof() will report a word=rounded size. By changing the 119 structure alignment to 8. GCC will conform to what is expected by 120 NetBSD. 121 122 This has several side effects that should be considered. 123 1. Structures will only be aligned to the size of the largest member. 124 i.e. structures containing only bytes will be byte aligned. 125 structures containing shorts will be half word aligned. 126 structures containing ints will be word aligned. 127 128 This means structures should be padded to a word boundary if 129 alignment of 32 is required for byte structures etc. 130 131 2. A potential performance penalty may exist if strings are no longer 132 word aligned. GCC will not be able to use word load/stores to copy 133 short strings. 134 135 This modification is not encouraged but with the present state of the 136 NetBSD source tree it is currently the only solution that meets the 137 requirements. */ 138#undef DEFAULT_STRUCTURE_SIZE_BOUNDARY 139#define DEFAULT_STRUCTURE_SIZE_BOUNDARY 8 140 141/* Clear the instruction cache from `BEG' to `END'. This makes a 142 call to the ARM32_SYNC_ICACHE architecture specific syscall. */ 143#define CLEAR_INSN_CACHE(BEG, END) \ 144{ \ 145 extern int sysarch(int number, void *args); \ 146 struct { \ 147 unsigned int addr; \ 148 int len; \ 149 } s; \ 150 s.addr = (unsigned int)(BEG); \ 151 s.len = (END) - (BEG); \ 152 (void)sysarch(0, &s); \ 153} 154