From 23ba15b7754ac8ff788bdf0699203f4d52833261 Mon Sep 17 00:00:00 2001 From: Ian Lance Taylor Date: Fri, 29 Jan 1993 23:24:20 +0000 Subject: [PATCH] Checkpoint. Can now create MIPS style armap hash tables. Fixed some linker problems. The linker still needs to learn to put SCommon symbols in .sbss rather than .bss. --- bfd/coff-mips.c | 224 ++++++++++++++++++++++++++++++++++++++++-------- 1 file changed, 189 insertions(+), 35 deletions(-) diff --git a/bfd/coff-mips.c b/bfd/coff-mips.c index 85a9056546b..082f6ba748e 100644 --- a/bfd/coff-mips.c +++ b/bfd/coff-mips.c @@ -435,17 +435,32 @@ DEFUN (ecoff_slurp_symbolic_info, (abfd), + internal_symhdr->iextMax); /* Read all the symbolic information at once. */ - raw_size = (internal_symhdr->cbLine * sizeof (unsigned char) - + internal_symhdr->idnMax * sizeof (struct dnr_ext) - + internal_symhdr->ipdMax * sizeof (struct pdr_ext) - + internal_symhdr->isymMax * sizeof (struct sym_ext) - + internal_symhdr->ioptMax * sizeof (struct opt_ext) - + internal_symhdr->iauxMax * sizeof (union aux_ext) - + internal_symhdr->issMax * sizeof (char) - + internal_symhdr->issExtMax * sizeof (char) - + internal_symhdr->ifdMax * sizeof (struct fdr_ext) - + internal_symhdr->crfd * sizeof (struct rfd_ext) - + internal_symhdr->iextMax * sizeof (struct ext_ext)); + raw_base = ecoff_data (abfd)->sym_filepos + sizeof (struct hdr_ext); + + if (internal_symhdr->cbExtOffset != 0) + raw_size = (internal_symhdr->cbExtOffset + - raw_base + + internal_symhdr->iextMax * sizeof (struct ext_ext)); + else + { + long cbline, issmax, issextmax; + + cbline = (internal_symhdr->cbLine + 3) &~ 4; + issmax = (internal_symhdr->issMax + 3) &~ 4; + issextmax = (internal_symhdr->issExtMax + 3) &~ 4; + raw_size = (cbline * sizeof (unsigned char) + + internal_symhdr->idnMax * sizeof (struct dnr_ext) + + internal_symhdr->ipdMax * sizeof (struct pdr_ext) + + internal_symhdr->isymMax * sizeof (struct sym_ext) + + internal_symhdr->ioptMax * sizeof (struct opt_ext) + + internal_symhdr->iauxMax * sizeof (union aux_ext) + + issmax * sizeof (char) + + issextmax * sizeof (char) + + internal_symhdr->ifdMax * sizeof (struct fdr_ext) + + internal_symhdr->crfd * sizeof (struct rfd_ext) + + internal_symhdr->iextMax * sizeof (struct ext_ext)); + } + if (raw_size == 0) { ecoff_data (abfd)->sym_filepos = 0; @@ -468,8 +483,6 @@ DEFUN (ecoff_slurp_symbolic_info, (abfd), ecoff_data (abfd)->raw_syments = raw; /* Get pointers for the numeric offsets in the HDRR structure. */ - raw_base = ecoff_data (abfd)->sym_filepos + sizeof (struct hdr_ext); - #define FIX(off1, off2, type) \ if (internal_symhdr->off1 == 0) \ ecoff_data (abfd)->off2 = (type *) NULL; \ @@ -572,6 +585,7 @@ DEFUN (ecoff_set_symbol_info, (abfd, ecoff_sym, asym, ext), case stProc: case stStaticProc: case stBlock: + case stNil: break; default: asym->flags = BSF_DEBUGGING; @@ -585,7 +599,11 @@ DEFUN (ecoff_set_symbol_info, (abfd, ecoff_sym, asym, ext), switch (ecoff_sym->sc) { case scNil: - asym->flags = BSF_DEBUGGING; + /* Used for compiler generated labels. Leave them in the + debugging section, and mark them as local. If BSF_DEBUGGING + is set, then nm does not display them for some reason. If no + flags are set then the linker whines about them. */ + asym->flags = BSF_LOCAL; break; case scText: asym->section = bfd_make_section_old_way (abfd, ".text"); @@ -597,7 +615,10 @@ DEFUN (ecoff_set_symbol_info, (abfd, ecoff_sym, asym, ext), break; case scBss: if (ext) - asym->section = &bfd_com_section; + { + asym->section = &bfd_com_section; + asym->flags = 0; + } else { asym->section = bfd_make_section_old_way (abfd, ".bss"); @@ -612,6 +633,8 @@ DEFUN (ecoff_set_symbol_info, (abfd, ecoff_sym, asym, ext), break; case scUndefined: asym->section = &bfd_und_section; + asym->flags = 0; + asym->value = 0; break; case scCdbLocal: case scBits: @@ -655,6 +678,7 @@ DEFUN (ecoff_set_symbol_info, (abfd, ecoff_sym, asym, ext), ecoff_scom_symbol_ptr = &ecoff_scom_symbol; } asym->section = &ecoff_scom_section; + asym->flags = 0; break; case scVarRegister: case scVariant: @@ -662,6 +686,8 @@ DEFUN (ecoff_set_symbol_info, (abfd, ecoff_sym, asym, ext), break; case scSUndefined: asym->section = &bfd_und_section; + asym->flags = 0; + asym->value = 0; break; case scInit: asym->section = bfd_make_section_old_way (abfd, ".init"); @@ -3050,7 +3076,7 @@ DEFUN (ecoff_write_object_contents, (abfd), ecoff_data (abfd)->sym_filepos = sym_base; - text_size = 0; + text_size = FILHSZ + AOUTSZ + abfd->section_count * SCNHSZ; text_start = 0; data_size = 0; data_start = 0; @@ -3361,9 +3387,7 @@ DEFUN (ecoff_write_object_contents, (abfd), ordering in the armap and the contents. The first four bytes in the armap are the number of symbol - definitions. This always seems to be a power of two, presumably - because ranlib uses a hash table of some sort. I don't know what - the hashing scheme is at the moment. + definitions. This is always a power of two. This is followed by the symbol definitions. Each symbol definition occupies 8 bytes. The first four bytes are the offset from the @@ -3373,11 +3397,20 @@ DEFUN (ecoff_write_object_contents, (abfd), are 0, then this is not actually a symbol definition, and it should be ignored. + The symbols are hashed into the armap with a closed hashing scheme. + See the functions below for the details of the algorithm. + + We could use the hash table when looking up symbols in a library. + This would require a new BFD target entry point to replace the + bfd_get_next_mapent function used by the linker. + After the symbol definitions comes four bytes holding the size of the string table, followed by the string table itself. */ /* The name of an archive headers looks like this: - __________E[BL]E[BL]_ (with a trailing space). */ + __________E[BL]E[BL]_ (with a trailing space). + The trailing space is changed to an X if the archive is changed to + indicate that the armap is out of date. */ #define ARMAP_BIG_ENDIAN 'B' #define ARMAP_LITTLE_ENDIAN 'L' @@ -3390,6 +3423,31 @@ DEFUN (ecoff_write_object_contents, (abfd), #define ARMAP_END_INDEX 14 #define ARMAP_END "_ " +/* This is a magic number used in the hashing algorithm. */ +#define ARMAP_HASH_MAGIC 0x9dd68ab5 + +/* This returns the hash value to use for a string. It also sets + *REHASH to the rehash adjustment if the first slot is taken. SIZE + is the number of entries in the hash table, and HLOG is the log + base 2 of SIZE. */ + +static unsigned int +ecoff_armap_hash (s, rehash, size, hlog) + CONST char *s; + unsigned int *rehash; + unsigned int size; + unsigned int hlog; +{ + unsigned int hash; + + hash = *s++; + while (*s != '\0') + hash = ((hash >> 27) | (hash << 5)) + *s++; + hash *= ARMAP_HASH_MAGIC; + *rehash = (hash & (size - 1)) | 1; + return hash >> (32 - hlog); +} + /* Read in the armap. */ static boolean @@ -3475,9 +3533,51 @@ DEFUN (ecoff_slurp_armap, (abfd), ardata->symdefs = (carsym *) symdef_ptr; stringbase = raw_ptr + count * (2 * LONG_SIZE) + LONG_SIZE; +#ifdef CHECK_ARMAP_HASH + { + unsigned int hlog; + + /* Double check that I have the hashing algorithm right by making + sure that every symbol can be looked up successfully. */ + hlog = 0; + for (i = 1; i < count; i <<= 1) + hlog++; + BFD_ASSERT (i == count); + + for (i = 0; i < count; i++, raw_ptr += 2 * LONG_SIZE) + { + unsigned int name_offset, file_offset; + unsigned int hash, rehash, srch; + + name_offset = bfd_h_get_32 (abfd, (PTR) raw_ptr); + file_offset = bfd_h_get_32 (abfd, (PTR) (raw_ptr + LONG_SIZE)); + if (file_offset == 0) + continue; + hash = ecoff_armap_hash (stringbase + name_offset, &rehash, count, + hlog); + if (hash == i) + continue; + + /* See if we can rehash to this location. */ + for (srch = (hash + rehash) & (count - 1); + srch != hash && srch != i; + srch = (srch + rehash) & (count - 1)) + BFD_ASSERT (bfd_h_get_32 (abfd, + (PTR) (raw_armap + + LONG_SIZE + + (srch * 2 * LONG_SIZE) + + LONG_SIZE)) + != 0); + BFD_ASSERT (srch == i); + } + } + + raw_ptr = raw_armap + LONG_SIZE; +#endif /* CHECK_ARMAP_HASH */ + for (i = 0; i < count; i++, raw_ptr += 2 * LONG_SIZE) { - unsigned long name_offset, file_offset; + unsigned int name_offset, file_offset; name_offset = bfd_h_get_32 (abfd, (PTR) raw_ptr); file_offset = bfd_h_get_32 (abfd, (PTR) (raw_ptr + LONG_SIZE)); @@ -3508,6 +3608,7 @@ DEFUN (ecoff_write_armap, (abfd, elength, map, orl_count, stridx), unsigned int orl_count AND int stridx) { + unsigned int hashsize, hashlog; unsigned int symdefsize; int padit; unsigned int stringsize; @@ -3516,16 +3617,23 @@ DEFUN (ecoff_write_armap, (abfd, elength, map, orl_count, stridx), struct ar_hdr hdr; struct stat statbuf; unsigned int i; - bfd_byte temp[4]; + bfd_byte temp[LONG_SIZE]; + bfd_byte *hashtable; bfd *current; bfd *last_elt; - symdefsize = orl_count * 8; + /* Ultrix appears to use as a hash table size the least power of two + greater than twice the number of entries. */ + for (hashlog = 0; (1 << hashlog) <= 2 * orl_count; hashlog++) + ; + hashsize = 1 << hashlog; + + symdefsize = hashsize * 2 * LONG_SIZE; padit = stridx % 2; stringsize = stridx + padit; /* Include 8 bytes to store symdefsize and stringsize in output. */ - mapsize = 4 + symdefsize + stringsize + 4; + mapsize = LONG_SIZE + symdefsize + stringsize + LONG_SIZE; firstreal = SARMAG + sizeof (struct ar_hdr) + mapsize + elength; @@ -3545,7 +3653,9 @@ DEFUN (ecoff_write_armap, (abfd, elength, map, orl_count, stridx), /* Write the timestamp of the archive header to be just a little bit later than the timestamp of the file, otherwise the linker will - complain that the index is out of date. */ + complain that the index is out of date. Actually, the Ultrix + linker just checks the archive name; the GNU linker may check the + date. */ if (stat (abfd->filename, &statbuf) < 0) statbuf.st_mtime = time ((PTR) NULL); sprintf (hdr.ar_date, "%ld", (long) (statbuf.st_mtime + 60)); @@ -3566,16 +3676,21 @@ DEFUN (ecoff_write_armap, (abfd, elength, map, orl_count, stridx), if (((char *)(&hdr))[i] == '\0') (((char *)(&hdr))[i]) = ' '; - bfd_write ((PTR) &hdr, 1, sizeof (struct ar_hdr), abfd); + if (bfd_write ((PTR) &hdr, 1, sizeof (struct ar_hdr), abfd) + != sizeof (struct ar_hdr)) + return false; - bfd_h_put_32 (abfd, symdefsize, temp); - bfd_write (temp, 1, LONG_SIZE, abfd); + bfd_h_put_32 (abfd, hashsize, temp); + if (bfd_write (temp, 1, LONG_SIZE, abfd) != LONG_SIZE) + return false; + hashtable = (bfd_byte *) bfd_zalloc (abfd, symdefsize); + current = abfd->archive_head; last_elt = current; for (i = 0; i < orl_count; i++) { - bfd_byte buff[8]; + unsigned int hash, rehash; /* Advance firstreal to the file position of this archive element. */ @@ -3592,21 +3707,60 @@ DEFUN (ecoff_write_armap, (abfd, elength, map, orl_count, stridx), last_elt = current; - bfd_h_put_32 (abfd, map[i].namidx, buff); - bfd_h_put_32 (abfd, firstreal, buff + LONG_SIZE); - bfd_write (buff, 1, 2 * LONG_SIZE, abfd); + hash = ecoff_armap_hash (*map[i].name, &rehash, hashsize, hashlog); + if (bfd_h_get_32 (abfd, (PTR) (hashtable + + (hash * 2 * LONG_SIZE) + + LONG_SIZE)) + != 0) + { + unsigned int srch; + + /* The desired slot is already taken. */ + for (srch = (hash + rehash) & (hashsize - 1); + srch != hash; + srch = (srch + rehash) & (hashsize - 1)) + if (bfd_h_get_32 (abfd, (PTR) (hashtable + + (srch * 2 * LONG_SIZE) + + LONG_SIZE)) + == 0) + break; + + BFD_ASSERT (srch != hash); + + hash = srch; + } + + bfd_h_put_32 (abfd, map[i].namidx, + (PTR) (hashtable + hash * 2 * LONG_SIZE)); + bfd_h_put_32 (abfd, firstreal, + (PTR) (hashtable + hash * 2 * LONG_SIZE + LONG_SIZE)); } + if (bfd_write (hashtable, 1, symdefsize, abfd) != symdefsize) + return false; + + bfd_release (abfd, hashtable); + /* Now write the strings. */ bfd_h_put_32 (abfd, stringsize, temp); - bfd_write (temp, 1, LONG_SIZE, abfd); + if (bfd_write (temp, 1, LONG_SIZE, abfd) != LONG_SIZE) + return false; for (i = 0; i < orl_count; i++) - bfd_write ((PTR) (*map[i].name), 1, strlen (*map[i].name) + 1, abfd); + { + bfd_size_type len; + + len = strlen (*map[i].name) + 1; + if (bfd_write ((PTR) (*map[i].name), 1, len, abfd) != len) + return false; + } /* The spec sez this should be a newline. But in order to be bug-compatible for DECstation ar we use a null. */ if (padit) - bfd_write ("\0", 1, 1, abfd); + { + if (bfd_write ("\0", 1, 1, abfd) != 1) + return false; + } return true; } -- 2.30.2