1 /* Definitions of target machine for GNU compiler, for DEC Alpha w/ELF.
2 Copyright (C) 1996-2023 Free Software Foundation, Inc.
3 Contributed by Richard Henderson (rth@tamu.edu).
4
5 This file is part of GCC.
6
7 GCC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3, or (at your option)
10 any later version.
11
12 GCC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3. If not see
19 <http://www.gnu.org/licenses/>. */
20
21 #undef CC1_SPEC
22 #define CC1_SPEC "%{G*}"
23
24 #undef ASM_SPEC
25 #define ASM_SPEC "%{G*} %{relax:-relax} %{mcpu=*:-m%*}"
26
27 /* Do not output a .file directive at the beginning of the input file. */
28
29 #undef TARGET_ASM_FILE_START_FILE_DIRECTIVE
30 #define TARGET_ASM_FILE_START_FILE_DIRECTIVE false
31
32 /* This is how to output an assembler line
33 that says to advance the location counter
34 to a multiple of 2**LOG bytes. */
35
36 #define ASM_OUTPUT_ALIGN(FILE,LOG) \
37 if ((LOG) != 0) \
38 fprintf (FILE, "\t.align %d\n", LOG);
39
40 /* This says how to output assembler code to declare an
41 uninitialized internal linkage data object. Under SVR4,
42 the linker seems to want the alignment of data objects
43 to depend on their types. We do exactly that here. */
44
45 #undef ASM_OUTPUT_ALIGNED_LOCAL
46 #define ASM_OUTPUT_ALIGNED_LOCAL(FILE, NAME, SIZE, ALIGN) \
47 do { \
48 if ((SIZE) <= (unsigned HOST_WIDE_INT) g_switch_value) \
49 switch_to_section (sbss_section); \
50 else \
51 switch_to_section (bss_section); \
52 ASM_OUTPUT_TYPE_DIRECTIVE (FILE, NAME, "object"); \
53 if (!flag_inhibit_size_directive) \
54 ASM_OUTPUT_SIZE_DIRECTIVE (FILE, NAME, SIZE); \
55 ASM_OUTPUT_ALIGN ((FILE), exact_log2((ALIGN) / BITS_PER_UNIT)); \
56 ASM_OUTPUT_LABEL(FILE, NAME); \
57 ASM_OUTPUT_SKIP((FILE), (SIZE) ? (SIZE) : 1); \
58 } while (0)
59
60 /* This says how to output assembler code to declare an
61 uninitialized external linkage data object. */
62
63 #undef ASM_OUTPUT_ALIGNED_BSS
64 #define ASM_OUTPUT_ALIGNED_BSS(FILE, DECL, NAME, SIZE, ALIGN) \
65 do { \
66 ASM_OUTPUT_ALIGNED_LOCAL (FILE, NAME, SIZE, ALIGN); \
67 } while (0)
68
69 #undef BSS_SECTION_ASM_OP
70 #define BSS_SECTION_ASM_OP "\t.section\t.bss"
71 #undef SBSS_SECTION_ASM_OP
72 #define SBSS_SECTION_ASM_OP "\t.section\t.sbss,\"aw\""
73 #undef SDATA_SECTION_ASM_OP
74 #define SDATA_SECTION_ASM_OP "\t.section\t.sdata,\"aw\""
75
76 /* This is how we tell the assembler that two symbols have the same value. */
77
78 #undef ASM_OUTPUT_DEF
79 #define ASM_OUTPUT_DEF(FILE, ALIAS, NAME) \
80 do { \
81 assemble_name(FILE, ALIAS); \
82 fputs(" = ", FILE); \
83 assemble_name(FILE, NAME); \
84 fputc('\n', FILE); \
85 } while (0)
86
87 #undef ASM_OUTPUT_DEF_FROM_DECLS
88 #define ASM_OUTPUT_DEF_FROM_DECLS(FILE, DECL, TARGET) \
89 do { \
90 const char *alias = XSTR (XEXP (DECL_RTL (DECL), 0), 0); \
91 const char *name = IDENTIFIER_POINTER (TARGET); \
92 if (TREE_CODE (DECL) == FUNCTION_DECL) \
93 { \
94 fputc ('$', FILE); \
95 assemble_name (FILE, alias); \
96 fputs ("..ng = $", FILE); \
97 assemble_name (FILE, name); \
98 fputs ("..ng\n", FILE); \
99 } \
100 ASM_OUTPUT_DEF (FILE, alias, name); \
101 } while (0)
102
103 /* This variable should be set to 'true' if the target ABI requires
104 unwinding tables even when exceptions are not used. */
105 #define TARGET_UNWIND_TABLES_DEFAULT true
106
107 /* Select a format to encode pointers in exception handling data. CODE
108 is 0 for data, 1 for code labels, 2 for function pointers. GLOBAL is
109 true if the symbol may be affected by dynamic relocations.
110
111 Since application size is already constrained to <2GB by the form of
112 the ldgp relocation, we can use a 32-bit pc-relative relocation to
113 static data. Dynamic data is accessed indirectly to allow for read
114 only EH sections. */
115 #define ASM_PREFERRED_EH_DATA_FORMAT(CODE,GLOBAL) \
116 (((GLOBAL) ? DW_EH_PE_indirect : 0) | DW_EH_PE_pcrel | DW_EH_PE_sdata4)
117
118 /* If defined, a C statement to be executed just prior to the output of
119 assembler code for INSN. */
120 #define FINAL_PRESCAN_INSN(INSN, OPVEC, NOPERANDS) \
121 (alpha_this_literal_sequence_number = 0, \
122 alpha_this_gpdisp_sequence_number = 0)
123 extern int alpha_this_literal_sequence_number;
124 extern int alpha_this_gpdisp_sequence_number;
125
126 /* Since the bits of the _init and _fini function is spread across
127 many object files, each potentially with its own GP, we must assume
128 we need to load our GP. Further, the .init/.fini section can
129 easily be more than 4MB away from the function to call so we can't
130 use bsr. */
131 #define CRT_CALL_STATIC_FUNCTION(SECTION_OP, FUNC) \
132 asm (SECTION_OP "\n" \
133 " br $29,1f\n" \
134 "1: ldgp $29,0($29)\n" \
135 " unop\n" \
136 " jsr $26," USER_LABEL_PREFIX #FUNC "\n" \
137 " .align 3\n" \
138 " .previous");
139
140 /* If we have the capability create headers for efficient EH lookup.
141 As of Jan 2002, only glibc 2.2.4 can actually make use of this, but
142 I imagine that other systems will catch up. In the meantime, it
143 doesn't harm to make sure that the data exists to be used later. */
144 #if defined(HAVE_LD_EH_FRAME_HDR)
145 #define LINK_EH_SPEC "%{!static|static-pie:--eh-frame-hdr} "
146 #endif