som.h revision 1.1.1.5 
1/* Definitions for SOM assembler support.
2   Copyright (C) 1999-2017 Free Software Foundation, Inc.
3
4This file is part of GCC.
5
6GCC is free software; you can redistribute it and/or modify
7it under the terms of the GNU General Public License as published by
8the Free Software Foundation; either version 3, or (at your option)
9any later version.
10
11GCC is distributed in the hope that it will be useful,
12but WITHOUT ANY WARRANTY; without even the implied warranty of
13MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14GNU General Public License for more details.
15
16You should have received a copy of the GNU General Public License
17along with GCC; see the file COPYING3.  If not see
18<http://www.gnu.org/licenses/>.  */
19
20/* So we can conditionalize small amounts of code in pa.c or pa.md.  */
21#undef TARGET_SOM
22#define TARGET_SOM 1
23
24/* We do not use BINCL stabs in SOM.
25   ??? If it does not hurt, we probably should to avoid useless divergence
26   from other embedded stabs implementations.  */
27#undef DBX_USE_BINCL
28
29#define DBX_LINES_FUNCTION_RELATIVE 1
30
31/* gdb needs a null N_SO at the end of each file for scattered loading.  */
32
33#define DBX_OUTPUT_NULL_N_SO_AT_MAIN_SOURCE_FILE_END
34
35/* HPUX has a program 'chatr' to list the dependencies of dynamically
36   linked executables and shared libraries.  */
37#define LDD_SUFFIX "chatr"
38/* Look for lines like "dynamic   /usr/lib/X11R5/libX11.sl"
39   or "static    /usr/lib/X11R5/libX11.sl".
40
41   HPUX 10.20 also has lines like "static branch prediction ..."
42   so we filter that out explicitly.
43
44   We also try to bound our search for libraries with marker
45   lines.  What a pain.  */
46#define PARSE_LDD_OUTPUT(PTR)					\
47do {								\
48  static int in_shlib_list = 0;					\
49  while (*PTR == ' ') PTR++;					\
50  if (strncmp (PTR, "shared library list:",			\
51	       sizeof ("shared library list:") - 1) == 0)	\
52    {								\
53      PTR = 0;							\
54      in_shlib_list = 1;					\
55    }								\
56  else if (strncmp (PTR, "shared library binding:",		\
57		    sizeof ("shared library binding:") - 1) == 0)\
58    {								\
59      PTR = 0;							\
60      in_shlib_list = 0;					\
61    }								\
62  else if (strncmp (PTR, "static branch prediction disabled",	\
63		    sizeof ("static branch prediction disabled") - 1) == 0)\
64    {								\
65      PTR = 0;							\
66      in_shlib_list = 0;					\
67    }								\
68  else if (in_shlib_list					\
69	   &&  strncmp (PTR, "dynamic", sizeof ("dynamic") - 1) == 0) \
70    {								\
71      PTR += sizeof ("dynamic") - 1;				\
72      while (*p == ' ') PTR++;					\
73    }								\
74  else if (in_shlib_list					\
75	   && strncmp (PTR, "static", sizeof ("static") - 1) == 0) \
76    {								\
77      PTR += sizeof ("static") - 1;				\
78      while (*p == ' ') PTR++;					\
79    }								\
80  else								\
81    PTR = 0;							\
82} while (0)
83
84/* Output the label for a function definition.  */
85#ifndef HP_FP_ARG_DESCRIPTOR_REVERSED
86#define ASM_DOUBLE_ARG_DESCRIPTORS(FILE, ARG0, ARG1)	\
87  do { fprintf (FILE, ",ARGW%d=FR", (ARG0));		\
88       fprintf (FILE, ",ARGW%d=FU", (ARG1));} while (0)
89#define DFMODE_RETURN_STRING ",RTNVAL=FU"
90#define SFMODE_RETURN_STRING ",RTNVAL=FR"
91#else
92#define ASM_DOUBLE_ARG_DESCRIPTORS(FILE, ARG0, ARG1)	\
93  do { fprintf (FILE, ",ARGW%d=FU", (ARG0));		\
94       fprintf (FILE, ",ARGW%d=FR", (ARG1));} while (0)
95#define DFMODE_RETURN_STRING ",RTNVAL=FR"
96#define SFMODE_RETURN_STRING ",RTNVAL=FU"
97#endif
98
99
100#define ASM_DECLARE_FUNCTION_NAME(FILE, NAME, DECL) \
101    do { tree fntype = TREE_TYPE (TREE_TYPE (DECL));			\
102	 tree tree_type = TREE_TYPE (DECL);				\
103	 tree parm;							\
104	 int i;								\
105	 if (TREE_PUBLIC (DECL) || TARGET_GAS)				\
106	   { 								\
107	     if (TREE_PUBLIC (DECL))					\
108	       {							\
109		 fputs ("\t.EXPORT ", FILE);				\
110		 assemble_name (FILE, NAME);				\
111		 fputs (",ENTRY,PRIV_LEV=3", FILE);			\
112	       }							\
113	     else							\
114	       {							\
115		 fputs ("\t.PARAM ", FILE);				\
116		 assemble_name (FILE, NAME);				\
117		 fputs (",PRIV_LEV=3", FILE);				\
118	       }							\
119	     for (parm = DECL_ARGUMENTS (DECL), i = 0; parm && i < 4;	\
120		  parm = DECL_CHAIN (parm))				\
121	       {							\
122		 if (TYPE_MODE (DECL_ARG_TYPE (parm)) == SFmode		\
123		     && ! TARGET_SOFT_FLOAT)				\
124		   fprintf (FILE, ",ARGW%d=FR", i++);			\
125		 else if (TYPE_MODE (DECL_ARG_TYPE (parm)) == DFmode	\
126			  && ! TARGET_SOFT_FLOAT)			\
127		   {							\
128		     if (i <= 2)					\
129		       {						\
130			 if (i == 1) i++;				\
131			 ASM_DOUBLE_ARG_DESCRIPTORS (FILE, i++, i++);	\
132		       }						\
133		     else						\
134		       break;						\
135		   }							\
136		 else							\
137		   {							\
138		     int arg_size =					\
139		       FUNCTION_ARG_SIZE (TYPE_MODE (DECL_ARG_TYPE (parm)),\
140					  DECL_ARG_TYPE (parm));	\
141		     /* Passing structs by invisible reference uses	\
142			one general register.  */			\
143		     if (arg_size > 2					\
144			 || TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))	\
145		       arg_size = 1;					\
146		     if (arg_size == 2 && i <= 2)			\
147		       {						\
148			 if (i == 1) i++;				\
149			 fprintf (FILE, ",ARGW%d=GR", i++);		\
150			 fprintf (FILE, ",ARGW%d=GR", i++);		\
151		       }						\
152		     else if (arg_size == 1)				\
153		       fprintf (FILE, ",ARGW%d=GR", i++);		\
154		     else						\
155		       i += arg_size;					\
156		   }							\
157	       }							\
158	     /* anonymous args */					\
159	     if (stdarg_p (tree_type))					\
160	       {							\
161		 for (; i < 4; i++)					\
162		   fprintf (FILE, ",ARGW%d=GR", i);			\
163	       }							\
164	     if (TYPE_MODE (fntype) == DFmode && ! TARGET_SOFT_FLOAT)	\
165	       fputs (DFMODE_RETURN_STRING, FILE);			\
166	     else if (TYPE_MODE (fntype) == SFmode && ! TARGET_SOFT_FLOAT) \
167	       fputs (SFMODE_RETURN_STRING, FILE);			\
168	     else if (fntype != void_type_node)				\
169	       fputs (",RTNVAL=GR", FILE);				\
170	     fputs ("\n", FILE);					\
171	   }} while (0)
172
173#define TARGET_ASM_FILE_START pa_som_file_start
174#define TARGET_ASM_INIT_SECTIONS pa_som_asm_init_sections
175
176/* String to output before writable data.  */
177#define DATA_SECTION_ASM_OP "\t.SPACE $PRIVATE$\n\t.SUBSPA $DATA$\n"
178
179/* String to output before uninitialized data.  */
180#define BSS_SECTION_ASM_OP "\t.SPACE $PRIVATE$\n\t.SUBSPA $BSS$\n"
181
182/* This is how to output a command to make the user-level label
183   named NAME defined for reference from other files.  We use
184   assemble_name_raw instead of assemble_name since a symbol in
185   a .IMPORT directive that isn't otherwise referenced is not
186   placed in the symbol table of the assembled object.
187
188   Failure to import a function reference can cause the HP linker
189   to segmentation fault!
190
191   Note that the SOM based tools need the symbol imported as a
192   CODE symbol, while the ELF based tools require the symbol to
193   be imported as an ENTRY symbol.  */
194
195#define ASM_OUTPUT_EXTERNAL(FILE, DECL, NAME) \
196  pa_hpux_asm_output_external ((FILE), (DECL), (NAME))
197#define ASM_OUTPUT_EXTERNAL_REAL(FILE, DECL, NAME) \
198  do { fputs ("\t.IMPORT ", FILE);					\
199       assemble_name_raw (FILE, NAME);					\
200       if (FUNCTION_NAME_P (NAME))					\
201	 fputs (",CODE\n", FILE);					\
202       else								\
203	 fputs (",DATA\n", FILE);					\
204     } while (0)
205
206/* The bogus HP assembler requires ALL external references to be
207   "imported", even library calls.  They look a bit different, so
208   here's this macro.
209
210   Also note not all libcall names are passed to pa_encode_section_info
211   (__main for example).  To make sure all libcall names have section
212   info recorded in them, we do it here.
213
214   We must also ensure that a libcall that has been previously
215   exported is not subsequently imported since the HP assembler may
216   change the type from an ENTRY to a CODE symbol.  This would make
217   the symbol local.  We are forced to use the identifier node
218   associated with the real assembler name for this check as the
219   symbol_ref available in ASM_DECLARE_FUNCTION_NAME is not the
220   same as the one used here.  As a result, we can't use flags
221   in the symbol_ref for this check.  The identifier check assumes
222   assemble_external_libcall is called before the symbol is used.  */
223
224#define ASM_OUTPUT_EXTERNAL_LIBCALL(FILE, RTL) \
225  do { const char *name;						\
226       tree id;								\
227									\
228       if (!function_label_operand (RTL, VOIDmode))			\
229	 pa_encode_label (RTL);						\
230									\
231       name = targetm.strip_name_encoding (XSTR ((RTL), 0));		\
232       id = maybe_get_identifier (name);				\
233       if (!id || !TREE_SYMBOL_REFERENCED (id))				\
234	 {								\
235	   fputs ("\t.IMPORT ", FILE);					\
236	   assemble_name_raw (FILE, XSTR ((RTL), 0));		       	\
237	   fputs (",CODE\n", FILE);					\
238	 }								\
239     } while (0)
240
241/* We want __gcc_plt_call to appear in every program built by
242   gcc, so we make a reference to it out of __main.
243   We use the asm statement to fool the optimizer into not
244   removing the dead (but important) initialization of
245   REFERENCE.  */
246
247#define DO_GLOBAL_DTORS_BODY			\
248do {						\
249  extern void __gcc_plt_call (void);		\
250  void (*reference)(void) = &__gcc_plt_call;	\
251  func_ptr *p;					\
252  __asm__ ("" : : "r" (reference));		\
253  for (p = __DTOR_LIST__ + 1; *p; )		\
254    (*p++) ();					\
255} while (0)
256
257/* This macro specifies the biggest alignment supported by the object
258   file format of this machine.
259
260   The .align directive in the HP assembler allows alignments up to 4096
261   bytes.  However, the maximum alignment of a global common symbol is 8
262   bytes for objects smaller than the page size (4096 bytes).  For larger
263   objects, the linker provides an alignment of 32 bytes.  Unfortunately,
264   this macro doesn't provide a mechanism to test for common symbols.  */
265#define MAX_OFILE_ALIGNMENT 32768
266
267/* The SOM linker hardcodes paths into binaries.  As a result, dotdots
268   must be removed from library prefixes to prevent binaries from depending
269   on the location of the GCC tool directory.  The downside is GCC
270   cannot be moved after installation using a symlink.  */
271#undef TARGET_ALWAYS_STRIP_DOTDOT
272#define TARGET_ALWAYS_STRIP_DOTDOT true
273
274/* If GAS supports weak, we can support weak when we have working linker
275   support for secondary definitions and are generating code for GAS.
276   This is primarily for one-only support as SOM doesn't allow undefined
277   weak symbols.  */
278#ifdef HAVE_GAS_WEAK
279#define TARGET_SUPPORTS_WEAK (TARGET_SOM_SDEF && TARGET_GAS)
280#else
281#define TARGET_SUPPORTS_WEAK 0
282#endif
283
284/* CVS GAS as of 4/28/04 supports a comdat parameter for the .nsubspa
285   directive.  This provides one-only linkage semantics even though we
286   don't have weak support.  */
287#ifdef HAVE_GAS_NSUBSPA_COMDAT
288#define SUPPORTS_SOM_COMDAT (TARGET_GAS)
289#else
290#define SUPPORTS_SOM_COMDAT 0
291#endif
292
293/* We can support one only if we support weak or comdat.  */
294#define SUPPORTS_ONE_ONLY (TARGET_SUPPORTS_WEAK || SUPPORTS_SOM_COMDAT)
295
296/* We use DECL_COMMON for uninitialized one-only variables as we don't
297   have linkonce .bss.  We use SOM secondary definitions or comdat for
298   initialized variables and functions.  */
299#define MAKE_DECL_ONE_ONLY(DECL) \
300  do {									\
301    if (TREE_CODE (DECL) == VAR_DECL					\
302        && (DECL_INITIAL (DECL) == 0					\
303            || DECL_INITIAL (DECL) == error_mark_node))			\
304      DECL_COMMON (DECL) = 1;						\
305    else if (TARGET_SUPPORTS_WEAK)					\
306      DECL_WEAK (DECL) = 1;						\
307  } while (0)
308
309/* This is how we tell the assembler that a symbol is weak.  The SOM
310   weak implementation uses the secondary definition (sdef) flag.
311
312   The behavior of sdef symbols is similar to ELF weak symbols in that
313   multiple definitions can occur without incurring a link error.
314   However, they differ in the following ways:
315     1) Undefined sdef symbols are not allowed.
316     2) The linker searches for undefined sdef symbols and will load an
317	archive library member to resolve an undefined sdef symbol.
318     3) The exported symbol from a shared library is a primary symbol
319        rather than a sdef symbol.  Thus, more care is needed in the
320	ordering of libraries.
321
322   It appears that the linker discards extra copies of "weak" functions
323   when linking shared libraries, independent of whether or not they
324   are in their own section.  In linking final executables, -Wl,-O can
325   be used to remove dead procedures.  Thus, support for named sections
326   is not needed and in previous testing caused problems with various
327   HP tools.  */
328#define ASM_WEAKEN_LABEL(FILE,NAME) \
329  do { fputs ("\t.weak\t", FILE);				\
330       assemble_name (FILE, NAME);				\
331       fputc ('\n', FILE);					\
332       targetm.asm_out.globalize_label (FILE, NAME);		\
333  } while (0)
334
335/* We can't handle weak aliases, and therefore can't support pragma weak.
336   Suppress the use of pragma weak in gthr-dce.h and gthr-posix.h.  */
337#define GTHREAD_USE_WEAK 0
338
339/* Shared library suffix.  Collect2 strips the version string after
340   this suffix when generating constructor/destructor names.  */
341#define SHLIB_SUFFIX ".sl"
342
343/* We don't have named sections.  */
344#define TARGET_HAVE_NAMED_SECTIONS false
345
346#define TARGET_ASM_TM_CLONE_TABLE_SECTION pa_som_tm_clone_table_section
347
348/* Generate specially named labels to identify DWARF 2 frame unwind
349   information.  */
350#define EH_FRAME_THROUGH_COLLECT2
351