/usr/src/gcc-4.6/debian/patches/m68k-atomic.diff is in gcc-4.6-source 4.6.4-6ubuntu2.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 | # DP: backport atomic builtin backend code for m68k from trunk
# DP: and add t-slibgcc-libgcc to m68k configuration by advice
# DP: of Mikel Pettersson to avoid running into PR40134 again
--- a/src/libgcc/config.host
+++ b/src/libgcc/config.host
@@ -383,9 +383,10 @@ m68k*-*-openbsd*)
;;
m68k-*-uclinux*) # Motorola m68k/ColdFire running uClinux with uClibc
;;
-m68k-*-linux*) # Motorola m68k's running GNU/Linux
+m68k-*-linux*) # Motorola m68k's running GNU/Linux
# with ELF format using glibc 2
# aka the GNU/Linux C library 6.
+ tmake_file="$tmake_file m68k/t-linux"
;;
m68k-*-rtems*)
;;
--- /dev/null
+++ b/src/libgcc/config/m68k/linux-atomic.c
@@ -0,0 +1,211 @@
+/* Linux-specific atomic operations for m68k Linux.
+ Copyright (C) 2011 Free Software Foundation, Inc.
+ Based on code contributed by CodeSourcery for ARM EABI Linux.
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 3, or (at your option) any later
+version.
+
+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+for more details.
+
+Under Section 7 of GPL version 3, you are granted additional
+permissions described in the GCC Runtime Library Exception, version
+3.1, as published by the Free Software Foundation.
+
+You should have received a copy of the GNU General Public License and
+a copy of the GCC Runtime Library Exception along with this program;
+see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
+<http://www.gnu.org/licenses/>. */
+
+/* Coldfire dropped the CAS instruction from the base M68K ISA.
+
+ GCC automatically issues a asm memory barrier when it encounters
+ a __sync_synchronize builtin. Thus, we do not need to define this
+ builtin.
+
+ We implement byte, short and int versions of each atomic operation
+ using the kernel helper defined below. There is no support for
+ 64-bit operations yet. */
+
+#include <asm/unistd.h>
+#include <stdbool.h>
+
+#ifndef __NR_atomic_cmpxchg_32
+#define __NR_atomic_cmpxchg_32 335
+#endif
+
+/* Kernel helper for compare-and-exchange a 32-bit value. */
+static inline unsigned
+__kernel_cmpxchg (unsigned *mem, unsigned oldval, unsigned newval)
+{
+ register unsigned *a0 asm("a0") = mem;
+ register unsigned d2 asm("d2") = oldval;
+ register unsigned d1 asm("d1") = newval;
+ register unsigned d0 asm("d0") = __NR_atomic_cmpxchg_32;
+
+ asm volatile ("trap #0"
+ : "=r"(d0), "=r"(d1), "=r"(a0)
+ : "r"(d0), "r"(d1), "r"(d2), "r"(a0)
+ : "memory", "a1");
+
+ return d0;
+}
+
+#define HIDDEN __attribute__ ((visibility ("hidden")))
+
+/* Big endian masks */
+#define INVERT_MASK_1 24
+#define INVERT_MASK_2 16
+
+#define MASK_1 0xffu
+#define MASK_2 0xffffu
+
+#define NAME_oldval(OP, WIDTH) __sync_fetch_and_##OP##_##WIDTH
+#define NAME_newval(OP, WIDTH) __sync_##OP##_and_fetch_##WIDTH
+
+#define WORD_SYNC_OP(OP, PFX_OP, INF_OP, RETURN) \
+ unsigned HIDDEN \
+ NAME##_##RETURN (OP, 4) (unsigned *ptr, unsigned val) \
+ { \
+ unsigned oldval, newval, cmpval = *ptr; \
+ \
+ do { \
+ oldval = cmpval; \
+ newval = PFX_OP (oldval INF_OP val); \
+ cmpval = __kernel_cmpxchg (ptr, oldval, newval); \
+ } while (__builtin_expect (oldval != cmpval, 0)); \
+ \
+ return RETURN; \
+ }
+
+#define SUBWORD_SYNC_OP(OP, PFX_OP, INF_OP, TYPE, WIDTH, RETURN) \
+ TYPE HIDDEN \
+ NAME##_##RETURN (OP, WIDTH) (TYPE *ptr, TYPE sval) \
+ { \
+ unsigned *wordptr = (unsigned *) ((unsigned long) ptr & ~3); \
+ unsigned int mask, shift, oldval, newval, cmpval, wval; \
+ \
+ shift = (((unsigned long) ptr & 3) << 3) ^ INVERT_MASK_##WIDTH; \
+ mask = MASK_##WIDTH << shift; \
+ wval = (sval & MASK_##WIDTH) << shift; \
+ \
+ cmpval = *wordptr; \
+ do { \
+ oldval = cmpval; \
+ newval = PFX_OP (oldval INF_OP wval); \
+ newval = (newval & mask) | (oldval & ~mask); \
+ cmpval = __kernel_cmpxchg (wordptr, oldval, newval); \
+ } while (__builtin_expect (oldval != cmpval, 0)); \
+ \
+ return (RETURN >> shift) & MASK_##WIDTH; \
+ }
+
+WORD_SYNC_OP (add, , +, oldval)
+WORD_SYNC_OP (sub, , -, oldval)
+WORD_SYNC_OP (or, , |, oldval)
+WORD_SYNC_OP (and, , &, oldval)
+WORD_SYNC_OP (xor, , ^, oldval)
+WORD_SYNC_OP (nand, ~, &, oldval)
+
+SUBWORD_SYNC_OP (add, , +, unsigned short, 2, oldval)
+SUBWORD_SYNC_OP (sub, , -, unsigned short, 2, oldval)
+SUBWORD_SYNC_OP (or, , |, unsigned short, 2, oldval)
+SUBWORD_SYNC_OP (and, , &, unsigned short, 2, oldval)
+SUBWORD_SYNC_OP (xor, , ^, unsigned short, 2, oldval)
+SUBWORD_SYNC_OP (nand, ~, &, unsigned short, 2, oldval)
+
+SUBWORD_SYNC_OP (add, , +, unsigned char, 1, oldval)
+SUBWORD_SYNC_OP (sub, , -, unsigned char, 1, oldval)
+SUBWORD_SYNC_OP (or, , |, unsigned char, 1, oldval)
+SUBWORD_SYNC_OP (and, , &, unsigned char, 1, oldval)
+SUBWORD_SYNC_OP (xor, , ^, unsigned char, 1, oldval)
+SUBWORD_SYNC_OP (nand, ~, &, unsigned char, 1, oldval)
+
+WORD_SYNC_OP (add, , +, newval)
+WORD_SYNC_OP (sub, , -, newval)
+WORD_SYNC_OP (or, , |, newval)
+WORD_SYNC_OP (and, , &, newval)
+WORD_SYNC_OP (xor, , ^, newval)
+WORD_SYNC_OP (nand, ~, &, newval)
+
+SUBWORD_SYNC_OP (add, , +, unsigned short, 2, newval)
+SUBWORD_SYNC_OP (sub, , -, unsigned short, 2, newval)
+SUBWORD_SYNC_OP (or, , |, unsigned short, 2, newval)
+SUBWORD_SYNC_OP (and, , &, unsigned short, 2, newval)
+SUBWORD_SYNC_OP (xor, , ^, unsigned short, 2, newval)
+SUBWORD_SYNC_OP (nand, ~, &, unsigned short, 2, newval)
+
+SUBWORD_SYNC_OP (add, , +, unsigned char, 1, newval)
+SUBWORD_SYNC_OP (sub, , -, unsigned char, 1, newval)
+SUBWORD_SYNC_OP (or, , |, unsigned char, 1, newval)
+SUBWORD_SYNC_OP (and, , &, unsigned char, 1, newval)
+SUBWORD_SYNC_OP (xor, , ^, unsigned char, 1, newval)
+SUBWORD_SYNC_OP (nand, ~, &, unsigned char, 1, newval)
+
+unsigned HIDDEN
+__sync_val_compare_and_swap_4 (unsigned *ptr, unsigned oldval, unsigned newval)
+{
+ return __kernel_cmpxchg (ptr, oldval, newval);
+}
+
+bool HIDDEN
+__sync_bool_compare_and_swap_4 (unsigned *ptr, unsigned oldval,
+ unsigned newval)
+{
+ return __kernel_cmpxchg (ptr, oldval, newval) == oldval;
+}
+
+#define SUBWORD_VAL_CAS(TYPE, WIDTH) \
+ TYPE HIDDEN \
+ __sync_val_compare_and_swap_##WIDTH (TYPE *ptr, TYPE soldval, \
+ TYPE snewval) \
+ { \
+ unsigned *wordptr = (unsigned *)((unsigned long) ptr & ~3); \
+ unsigned int mask, shift, woldval, wnewval; \
+ unsigned oldval, newval, cmpval; \
+ \
+ shift = (((unsigned long) ptr & 3) << 3) ^ INVERT_MASK_##WIDTH; \
+ mask = MASK_##WIDTH << shift; \
+ woldval = (soldval & MASK_##WIDTH) << shift; \
+ wnewval = (snewval & MASK_##WIDTH) << shift; \
+ cmpval = *wordptr; \
+ \
+ do { \
+ oldval = cmpval; \
+ if ((oldval & mask) != woldval) \
+ break; \
+ newval = (oldval & ~mask) | wnewval; \
+ cmpval = __kernel_cmpxchg (wordptr, oldval, newval); \
+ } while (__builtin_expect (oldval != cmpval, 0)); \
+ \
+ return (oldval >> shift) & MASK_##WIDTH; \
+ }
+
+SUBWORD_VAL_CAS (unsigned short, 2)
+SUBWORD_VAL_CAS (unsigned char, 1)
+
+#define SUBWORD_BOOL_CAS(TYPE, WIDTH) \
+ bool HIDDEN \
+ __sync_bool_compare_and_swap_##WIDTH (TYPE *ptr, TYPE oldval, \
+ TYPE newval) \
+ { \
+ return (__sync_val_compare_and_swap_##WIDTH (ptr, oldval, newval) \
+ == oldval); \
+ }
+
+SUBWORD_BOOL_CAS (unsigned short, 2)
+SUBWORD_BOOL_CAS (unsigned char, 1)
+
+#undef NAME_oldval
+#define NAME_oldval(OP, WIDTH) __sync_lock_##OP##_##WIDTH
+#define COMMA ,
+
+WORD_SYNC_OP (test_and_set, , COMMA, oldval)
+SUBWORD_SYNC_OP (test_and_set, , COMMA, unsigned short, 1, oldval)
+SUBWORD_SYNC_OP (test_and_set, , COMMA, unsigned short, 2, oldval)
--- /dev/null
+++ b/src/libgcc/config/m68k/t-linux
@@ -0,0 +1 @@
+LIB2ADD_ST = $(srcdir)/config/m68k/linux-atomic.c
--- a/src/gcc/config.gcc
+++ b/src/gcc/config.gcc
@@ -1792,7 +1792,7 @@ m68k-*-uclinux*) # Motorola m68k/ColdFi
tm_defines="${tm_defines} MOTOROLA=1"
tmake_file="m68k/t-floatlib m68k/t-uclinux m68k/t-mlibs"
;;
-m68k-*-linux*) # Motorola m68k's running GNU/Linux
+m68k-*-linux*) # Motorola m68k's running GNU/Linux
# with ELF format using glibc 2
# aka the GNU/Linux C library 6.
default_m68k_cpu=68020
@@ -1807,6 +1807,7 @@ m68k-*-linux*) # Motorola m68k's runnin
if test x$sjlj != x1; then
tmake_file="$tmake_file m68k/t-slibgcc-elf-ver"
fi
+ tmake_file="$tmake_file t-slibgcc-libgcc"
;;
m68k-*-rtems*)
default_m68k_cpu=68020
|