1 /* Target definitions for GNU compiler for mc680x0 running System V.4
2 Copyright (C) 1991, 1993 Free Software Foundation, Inc.
4 Written by Ron Guilmette (rfg@ncd.com) and Fred Fish (fnf@cygnus.com).
6 This file is part of GNU CC.
8 GNU CC 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 2, or (at your option)
13 GNU CC 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.
18 You should have received a copy of the GNU General Public License
19 along with GNU CC; see the file COPYING. If not, write to
20 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
22 /* Use SGS_* macros to control compilation in m68k.md */
24 #define SGS_SWITCH_TABLES /* Different switch table handling */
26 #include "m68k/sgs.h" /* The m68k/SVR4 assembler is SGS based */
27 #include "svr4.h" /* Pick up the generic SVR4 macros */
29 /* See m68k.h. 7 means 68020 with 68881. */
31 #ifndef TARGET_DEFAULT
32 #define TARGET_DEFAULT (5 /*68020*/ + 2 /*68881*/)
35 /* Override the definition of NO_DOLLAR_IN_LABEL in svr4.h, for special
36 g++ assembler names. When this is defined, g++ uses embedded '.'
37 characters and some m68k assemblers have problems with this. The
38 chances are much greater that any particular assembler will permit
39 embedded '$' characters. */
41 #undef NO_DOLLAR_IN_LABEL
43 /* Define PCC_STATIC_STRUCT_RETURN if the convention on the target machine
44 is to use the nonreentrant technique for returning structure and union
45 values, as commonly implemented by the AT&T Portable C Compiler (PCC).
46 When defined, the gcc option -fpcc-struct-return can be used to cause
47 this form to be generated. When undefined, the option does nothing.
48 For m68k SVR4, the convention is to use a reentrant technique compatible
49 with the gcc default, so override the definition of this macro in m68k.h */
51 #undef PCC_STATIC_STRUCT_RETURN
53 /* Provide a set of pre-definitions and pre-assertions appropriate for
54 the m68k running svr4. __svr4__ is our extension. */
56 #define CPP_PREDEFINES \
57 "-Dm68k -Dunix -D__svr4__ -D__motorola__ \
58 -Asystem(unix) -Asystem(svr4) -Acpu(m68k) -Amachine(m68k)"
60 /* Test to see if the target includes a 68881 by default, and use CPP_SPEC
61 to control whether or not __HAVE_68881__ is defined by default or not.
62 If a 68881 is the default, gcc will use inline 68881 instructions, by
63 predefining __HAVE_68881__, unless -msoft-float is specified.
64 If a 68881 is not the default, gcc will only define __HAVE_68881__ if
65 -m68881 is specified. */
67 #if TARGET_DEFAULT & 2
68 #define CPP_SPEC "%{!msoft-float:-D__HAVE_68881__}"
70 #define CPP_SPEC "%{m68881:-D__HAVE_68881__}"
73 /* Output assembler code to FILE to increment profiler label # LABELNO
74 for profiling a function entry. We override the definition in m68k.h
75 and match the way the native m68k/SVR4 compiler does profiling, with the
76 address of the profile counter in a1, not a0, and using bsr rather
79 #undef FUNCTION_PROFILER
80 #define FUNCTION_PROFILER(FILE, LABELNO) \
81 asm_fprintf ((FILE), "\tlea.l\t(%LLP%d,%Rpc),%Ra1\n\tbsr\t_mcount\n", \
84 /* Local common symbols are declared to the assembler with ".lcomm" rather
85 than ".bss", so override the definition in svr4.h */
88 #define BSS_ASM_OP ".lcomm"
90 /* Register in which address to store a structure value is passed to a
91 function. The default in m68k.h is a1. For m68k/SVR4 it is a0. */
93 #undef STRUCT_VALUE_REGNUM
94 #define STRUCT_VALUE_REGNUM 8
96 #define ASM_COMMENT_START "#"
98 #undef TYPE_OPERAND_FMT
99 #define TYPE_OPERAND_FMT "@%s"
101 /* Define how the m68k registers should be numbered for Dwarf output.
102 The numbering provided here should be compatible with the native
103 SVR4 SDB debugger in the m68k/SVR4 reference port, where d0-d7
104 are 0-7, a0-a8 are 8-15, and fp0-fp7 are 16-23. */
106 #define DBX_REGISTER_NUMBER(REGNO) (REGNO)
108 /* The ASM_OUTPUT_SKIP macro is first defined in m68k.h, using ".skip".
109 It is then overridden by m68k/sgs.h to use ".space", and again by svr4.h
110 to use ".zero". The m68k/SVR4 assembler uses ".space", so repeat the
111 definition from m68k/sgs.h here. Note that ASM_NO_SKIP_IN_TEXT is
112 defined in m68k/sgs.h, so we don't have to repeat it here. */
114 #undef ASM_OUTPUT_SKIP
115 #define ASM_OUTPUT_SKIP(FILE,SIZE) \
116 fprintf (FILE, "\t%s %u\n", SPACE_ASM_OP, (SIZE))
118 /* 1 if N is a possible register number for a function value.
119 For m68k/SVR4 allow d0, a0, or fp0 as return registers, for integral,
120 pointer, or floating types, respectively. Reject fp0 if not using a
121 68881 coprocessor. */
123 #undef FUNCTION_VALUE_REGNO_P
124 #define FUNCTION_VALUE_REGNO_P(N) \
125 ((N) == 0 || (N) == 8 || (TARGET_68881 && (N) == 16))
127 /* Define this to be true when FUNCTION_VALUE_REGNO_P is true for
128 more than one register. */
130 #undef NEEDS_UNTYPED_CALL
131 #define NEEDS_UNTYPED_CALL 1
133 /* Define how to generate (in the callee) the output value of a function
134 and how to find (in the caller) the value returned by a function. VALTYPE
135 is the data type of the value (as a tree). If the precise function being
136 called is known, FUNC is its FUNCTION_DECL; otherwise, FUNC is 0.
137 For m68k/SVR4 generate the result in d0, a0, or fp0 as appropriate. */
139 #undef FUNCTION_VALUE
140 #define FUNCTION_VALUE(VALTYPE, FUNC) \
141 (TREE_CODE (VALTYPE) == REAL_TYPE && TARGET_68881 \
142 ? gen_rtx (REG, TYPE_MODE (VALTYPE), 16) \
143 : (TREE_CODE (VALTYPE) == POINTER_TYPE \
144 ? gen_rtx (REG, TYPE_MODE (VALTYPE), 8) \
145 : gen_rtx (REG, TYPE_MODE (VALTYPE), 0)))
147 /* For compatibility with the large body of existing code which does not
148 always properly declare external functions returning pointer types, the
149 m68k/SVR4 convention is to copy the value returned for pointer functions
150 from a0 to d0 in the function epilogue, so that callers that have
151 neglected to properly declare the callee can still find the correct return
154 extern int current_function_returns_pointer;
155 #define FUNCTION_EXTRA_EPILOGUE(FILE, SIZE) \
157 if ((current_function_returns_pointer) && \
158 ! find_equiv_reg (0, get_last_insn (), 0, 0, 0, 8, Pmode)) \
159 asm_fprintf (FILE, "\tmov.l %Ra0,%Rd0\n"); \
162 /* Define how to find the value returned by a library function assuming the
164 For m68k/SVR4 look for integer values in d0, pointer values in d0
165 (returned in both d0 and a0), and floating values in fp0. */
168 #define LIBCALL_VALUE(MODE) \
169 (((MODE) == SFmode || (MODE) == DFmode) && TARGET_68881 \
170 ? gen_rtx (REG, (MODE), 16) \
171 : gen_rtx (REG, (MODE), 0))
173 /* Boundary (in *bits*) on which stack pointer should be aligned.
174 The m68k/SVR4 convention is to keep the stack pointer longword aligned. */
176 #undef STACK_BOUNDARY
177 #define STACK_BOUNDARY 32
179 /* Alignment of field after `int : 0' in a structure.
180 For m68k/SVR4, this is the next longword boundary. */
182 #undef EMPTY_FIELD_BOUNDARY
183 #define EMPTY_FIELD_BOUNDARY 32
185 /* No data type wants to be aligned rounder than this.
186 For m68k/SVR4, some types (doubles for example) are aligned on 8 byte
189 #undef BIGGEST_ALIGNMENT
190 #define BIGGEST_ALIGNMENT 64
192 /* SVR4 m68k assembler is bitching on the `comm i,1,1' which askes for
193 1 byte alignment. Don't generate alignment for COMMON seems to be
194 safer until we the assembler is fixed. */
195 #undef ASM_OUTPUT_ALIGNED_COMMON
196 /* Same problem with this one. */
197 #undef ASM_OUTPUT_ALIGNED_LOCAL
199 /* The `string' directive on m68k svr4 does not handle string with
200 escape char (ie., `\') right. Use normal way to output ASCII bytes
201 seems to be safer. */
202 #undef ASM_OUTPUT_ASCII
203 #define ASM_OUTPUT_ASCII(FILE,PTR,LEN) \
205 register int sp = 0, lp = 0, ch; \
206 fprintf ((FILE), "\t%s ", BYTE_ASM_OP); \
209 if (ch > ' ' && ! (ch & 0x80) && ch != '\\') \
211 fprintf ((FILE), "'%c", ch); \
215 fprintf ((FILE), "0x%x", ch); \
219 if ((sp % 10) == 0) \
221 fprintf ((FILE), "\n\t%s ", BYTE_ASM_OP); \
225 putc (',', (FILE)); \
228 } while (sp < (LEN)); \
229 putc ('\n', (FILE)); \
232 /* SVR4 m68k assembler is bitching on the syntax `2.b'.
233 So use the "LLDnnn-LLnnn" format. Define LLDnnn after the table. */
235 #undef ASM_OUTPUT_CASE_END
236 #define ASM_OUTPUT_CASE_END(FILE,NUM,TABLE) \
238 if (switch_table_difference_label_flag) \
239 asm_fprintf ((FILE), "\t%s %LLD%d,%LL%d\n", SET_ASM_OP, (NUM), (NUM));\
240 switch_table_difference_label_flag = 0; \
243 int switch_table_difference_label_flag;
245 #undef ASM_OUTPUT_COMMON
246 #undef ASM_OUTPUT_LOCAL
247 #define ASM_OUTPUT_COMMON(FILE, NAME, SIZE, ROUNDED) \
248 ( fputs (".comm ", (FILE)), \
249 assemble_name ((FILE), (NAME)), \
250 fprintf ((FILE), ",%u\n", (SIZE)))
252 #define ASM_OUTPUT_LOCAL(FILE, NAME, SIZE, ROUNDED) \
253 ( fputs (".lcomm ", (FILE)), \
254 assemble_name ((FILE), (NAME)), \
255 fprintf ((FILE), ",%u\n", (SIZE)))
257 /* Override the definition in svr4.h. In m68k svr4, using swbeg is the
258 standard way to do switch table. */
259 #undef ASM_OUTPUT_BEFORE_CASE_LABEL
260 #define ASM_OUTPUT_BEFORE_CASE_LABEL(FILE,PREFIX,NUM,TABLE) \
261 fprintf ((FILE), "\t%s &%d\n", SWBEG_ASM_OP, XVECLEN (PATTERN (TABLE), 1));
263 /* In m68k svr4, a symbol_ref rtx can be a valid PIC operand if it is an
264 operand of a function call. */
265 #undef LEGITIMATE_PIC_OPERAND_P
266 #define LEGITIMATE_PIC_OPERAND_P(X) \
267 (! symbolic_operand (X, VOIDmode) \
268 || ((GET_CODE(X) == SYMBOL_REF) && SYMBOL_REF_FLAG(X)))
270 /* Turn off function cse if we are doing PIC. We always want function call
271 to be done as `bsr foo@PLTPC', so it will force the assembler to create
272 the PLT entry for `foo'. Doing function cse will cause the address of `foo'
273 to be loaded into a register, which is exactly what we want to avoid when
274 we are doing PIC on svr4 m68k. */
275 #undef OVERRIDE_OPTIONS
276 #define OVERRIDE_OPTIONS \
278 if (flag_pic) flag_no_function_cse = 1; \
279 if (! TARGET_68020 && flag_pic == 2) \
280 error("-fPIC is not currently supported on the 68000 or 68010\n"); \