diff options
Diffstat (limited to 'externals/aterm-aliasing.patch')
| -rw-r--r-- | externals/aterm-aliasing.patch | 224 |
1 files changed, 224 insertions, 0 deletions
diff --git a/externals/aterm-aliasing.patch b/externals/aterm-aliasing.patch new file mode 100644 index 000000000000..c1dfc3e0e737 --- /dev/null +++ b/externals/aterm-aliasing.patch @@ -0,0 +1,224 @@ +diff -rc aterm-1142707243.10633/aterm/aterm.c aterm/aterm/aterm.c +*** aterm-1142707243.10633/aterm/aterm.c 2006-02-08 11:35:28.000000000 +0100 +--- aterm/aterm/aterm.c 2006-04-25 17:10:52.000000000 +0200 +*************** +*** 193,198 **** +--- 193,199 ---- + /* that have char == 2 bytes, and sizeof(header_type) == 2 */ + assert(sizeof(header_type) == sizeof(ATerm *)); + assert(sizeof(header_type) >= 4); ++ assert(sizeof(ATerm) == sizeof(MachineWord)); + + /*}}} */ + /*{{{ Initialize buffer */ +diff -rc aterm-1142707243.10633/aterm/memory.c aterm/aterm/memory.c +*** aterm-1142707243.10633/aterm/memory.c 2006-03-09 15:02:56.000000000 +0100 +--- aterm/aterm/memory.c 2006-04-25 18:22:00.000000000 +0200 +*************** +*** 119,130 **** + hash_number(tmp,3)) + */ + + #define HASHNUMBER3(t)\ +! FINISH(COMBINE(START(((MachineWord*)t)[0]), ((MachineWord*)t)[2])) + + #define HASHNUMBER4(t)\ +! FINISH(COMBINE(COMBINE(START(((MachineWord*)t)[0]), \ +! ((MachineWord*)t)[2]),((MachineWord*)t)[3])) + + #define HASHINT(val) \ + FINISH(COMBINE(START( (AT_INT<<SHIFT_TYPE) ), val)) +--- 119,171 ---- + hash_number(tmp,3)) + */ + ++ /* The ATerm library use some heavy aliasing. For instance, the ++ various ATermXXX structures are referenced through MachineWord ++ arrays. This is not generally allowed by the C standard --- see ++ C99, section 6.5, clause 7. In particular, this means that you ++ cannot assign something through an ATermXXX pointer, e.g., ++ ++ protoAppl->header = header; ++ ++ and then read it through a MachineWord*, e.g., ++ ++ hnr = hash_number((ATerm) protoAppl, 2); ++ ++ (hash_number walks over the term by casting it to a MachineWord*). ++ ++ However, the same clause of the C standard also specifies that you ++ *can* read the memory location through a union type that contains ++ both the original type (e.g. ATermAppl) and the type used to read ++ the memory location (e.g. MachineWord). That's what we do ++ below: we have a union of all the types that occur in the various ++ ATerm types. We then read the "w" element of the union. The ++ compiler is not allowed to assume absence of aliasing with the ++ other types in the union. ++ ++ A better solution would be to hash the term through a character ++ pointer (since *any* memory location can be legally read as a ++ character), but I'm too lazy right now. Performance might also ++ suffer if we do that. */ ++ ++ typedef union ++ { ++ MachineWord w; ++ header_type header; ++ ATerm term; ++ ATermList list; ++ int i; ++ double d; ++ void* p; ++ } Aliaser; ++ ++ #define GET_WORD(t, n) (((Aliaser*) (((MachineWord*) t) + n))->w) ++ + #define HASHNUMBER3(t)\ +! FINISH(COMBINE(START(GET_WORD(t, 0)), GET_WORD(t, 2))) + + #define HASHNUMBER4(t)\ +! FINISH(COMBINE(COMBINE(START(GET_WORD(t, 0)), \ +! GET_WORD(t, 2)), GET_WORD(t, 3))) + + #define HASHINT(val) \ + FINISH(COMBINE(START( (AT_INT<<SHIFT_TYPE) ), val)) +*************** +*** 132,144 **** + + #endif /* HASHPEM */ + +! #define PROTO_APPL_ARGS ((ATerm *) (protoTerm + ARG_OFFSET)) + + #define SET_PROTO_APPL_ARG(i, a) \ +! (PROTO_APPL_ARGS[(i)] = (a)) + + #define GET_PROTO_APPL_ARG(i) \ +! (PROTO_APPL_ARGS[(i)]) + + #define CHECK_TERM(t) \ + assert((t) != NULL \ +--- 173,185 ---- + + #endif /* HASHPEM */ + +! #define PROTO_APPL_ARGS (protoTerm + ARG_OFFSET) + + #define SET_PROTO_APPL_ARG(i, a) \ +! (PROTO_APPL_ARGS[(i)] = (MachineWord) (a)) + + #define GET_PROTO_APPL_ARG(i) \ +! ((ATerm) PROTO_APPL_ARGS[(i)]) + + #define CHECK_TERM(t) \ + assert((t) != NULL \ +*************** +*** 323,336 **** + #else + static HashNumber hash_number(ATerm t, int size) + { +- MachineWord *words = (MachineWord *) t; + int i; + HashNumber hnr; + +! hnr = START(HIDE_AGE_MARK(words[0])); + + for (i=2; i<size; i++) { +! hnr = COMBINE(hnr, words[i]); + } + + return FINISH(hnr); +--- 364,376 ---- + #else + static HashNumber hash_number(ATerm t, int size) + { + int i; + HashNumber hnr; + +! hnr = START(HIDE_AGE_MARK(GET_WORD(t, 0))); + + for (i=2; i<size; i++) { +! hnr = COMBINE(hnr, GET_WORD(t, i)); + } + + return FINISH(hnr); +*************** +*** 338,351 **** + + static HashNumber hash_number_anno(ATerm t, int size, ATerm anno) + { +- MachineWord *words = (MachineWord *) t; + int i; + HashNumber hnr; + +! hnr = START(HIDE_AGE_MARK(words[0])); + + for (i=2; i<size; i++) { +! hnr = COMBINE(hnr, words[i]); + } + hnr = COMBINE(hnr, (MachineWord)anno); + +--- 378,390 ---- + + static HashNumber hash_number_anno(ATerm t, int size, ATerm anno) + { + int i; + HashNumber hnr; + +! hnr = START(HIDE_AGE_MARK(GET_WORD(t, 0))); + + for (i=2; i<size; i++) { +! hnr = COMBINE(hnr, GET_WORD(t, i)); + } + hnr = COMBINE(hnr, (MachineWord)anno); + +*************** +*** 1639,1645 **** + protoAppl->header = header; + CHECK_HEADER(protoAppl->header); + +! if (args != PROTO_APPL_ARGS) { + for (i=0; i<arity; i++) { + CHECK_TERM(args[i]); + SET_PROTO_APPL_ARG(i, args[i]); +--- 1678,1684 ---- + protoAppl->header = header; + CHECK_HEADER(protoAppl->header); + +! if (args != (ATerm *) PROTO_APPL_ARGS) { + for (i=0; i<arity; i++) { + CHECK_TERM(args[i]); + SET_PROTO_APPL_ARG(i, args[i]); +*************** +*** 1680,1686 **** + hashtable[hnr] = cur; + } + +! if (args != PROTO_APPL_ARGS) { + for (i=0; i<arity; i++) { + protected_buffer[i] = NULL; + } +--- 1719,1725 ---- + hashtable[hnr] = cur; + } + +! if (args != (ATerm *) PROTO_APPL_ARGS) { + for (i=0; i<arity; i++) { + protected_buffer[i] = NULL; + } +*************** +*** 2144,2150 **** + } + SET_PROTO_APPL_ARG(n, arg); + +! result = ATmakeApplArray(sym, PROTO_APPL_ARGS); + annos = AT_getAnnotations((ATerm)appl); + if (annos != NULL) { + result = (ATermAppl)AT_setAnnotations((ATerm)result, annos); +--- 2183,2189 ---- + } + SET_PROTO_APPL_ARG(n, arg); + +! result = ATmakeApplArray(sym, (ATerm *) PROTO_APPL_ARGS); + annos = AT_getAnnotations((ATerm)appl); + if (annos != NULL) { + result = (ATermAppl)AT_setAnnotations((ATerm)result, annos); |