diff options
Diffstat (limited to 'gas/write.c')
| -rw-r--r-- | gas/write.c | 320 |
1 files changed, 150 insertions, 170 deletions
diff --git a/gas/write.c b/gas/write.c index 4a754f4..4ee88c2 100644 --- a/gas/write.c +++ b/gas/write.c @@ -175,11 +175,11 @@ write_object_file () { #ifdef VMS /* - * Under VAX/VMS, the linker (and PSECT specifications) - * take care of correctly aligning the segments. - * Doing the alignment here (on initialized data) can - * mess up the calculation of global data PSECT sizes. - */ + * Under VAX/VMS, the linker (and PSECT specifications) + * take care of correctly aligning the segments. + * Doing the alignment here (on initialized data) can + * mess up the calculation of global data PSECT sizes. + */ #undef SUB_SEGMENT_ALIGN #define SUB_SEGMENT_ALIGN ((frchainP->frch_seg != SEG_DATA) ? 2 : 0) #endif /* VMS */ @@ -188,9 +188,9 @@ write_object_file () /* frag_align will have left a new frag. */ /* Use this last frag for an empty ".fill". */ /* - * For this segment ... - * Create a last frag. Do not leave a "being filled in frag". - */ + * For this segment ... + * Create a last frag. Do not leave a "being filled in frag". + */ frag_wane (frag_now); frag_now->fr_fix = 0; know (frag_now->fr_next == NULL); @@ -199,21 +199,21 @@ write_object_file () } /* walk the frag chain */ /* - * From now on, we don't care about sub-segments. - * Build one frag chain for each segment. Linked thru fr_next. - * We know that there is at least 1 text frchain & at least 1 data - * frchain. - */ + * From now on, we don't care about sub-segments. + * Build one frag chain for each segment. Linked thru fr_next. + * We know that there is at least 1 text frchain & at least 1 data + * frchain. + */ remove_subsegs (frchain_root, SEG_TEXT, &text_frag_root, &text_last_frag); remove_subsegs (data0_frchainP, SEG_DATA, &data_frag_root, &data_last_frag); remove_subsegs (bss0_frchainP, SEG_BSS, &bss_frag_root, &bss_last_frag); /* - * We have two segments. If user gave -R flag, then we must put the - * data frags into the text segment. Do this before relaxing so - * we know to take advantage of -R and make shorter addresses. - */ + * We have two segments. If user gave -R flag, then we must put the + * data frags into the text segment. Do this before relaxing so + * we know to take advantage of -R and make shorter addresses. + */ #ifndef OBJ_AOUT if (flagseen['R']) { @@ -238,20 +238,20 @@ write_object_file () relax_segment (data_frag_root, SEG_DATA); relax_segment (bss_frag_root, SEG_BSS); /* - * Now the addresses of frags are correct within the segment. - */ + * Now the addresses of frags are correct within the segment. + */ know (text_last_frag->fr_type == rs_fill && text_last_frag->fr_offset == 0); H_SET_TEXT_SIZE (&headers, text_last_frag->fr_address); text_last_frag->fr_address = H_GET_TEXT_SIZE (&headers); /* - * Join the 2 segments into 1 huge segment. - * To do this, re-compute every rn_address in the SEG_DATA frags. - * Then join the data frags after the text frags. - * - * Determine a_data [length of data segment]. - */ + * Join the 2 segments into 1 huge segment. + * To do this, re-compute every rn_address in the SEG_DATA frags. + * Then join the data frags after the text frags. + * + * Determine a_data [length of data segment]. + */ if (data_frag_root) { register relax_addressT slide; @@ -264,10 +264,10 @@ write_object_file () #ifdef OBJ_BOUT #define RoundUp(N,S) (((N)+(S)-1)&-(S)) /* For b.out: If the data section has a strict alignment - requirement, its load address in the .o file will be - rounded up from the size of the text section. These - two values are *not* the same! Similarly for the bss - section.... */ + requirement, its load address in the .o file will be + rounded up from the size of the text section. These + two values are *not* the same! Similarly for the bss + section.... */ slide = RoundUp (slide, 1 << section_alignment[SEG_DATA]); #endif @@ -320,26 +320,26 @@ write_object_file () H_SET_BSS_SIZE (&headers, local_bss_counter); /* - * - * Crawl the symbol chain. - * - * For each symbol whose value depends on a frag, take the address of - * that frag and subsume it into the value of the symbol. - * After this, there is just one way to lookup a symbol value. - * Values are left in their final state for object file emission. - * We adjust the values of 'L' local symbols, even if we do - * not intend to emit them to the object file, because their values - * are needed for fix-ups. - * - * Unless we saw a -L flag, remove all symbols that begin with 'L' - * from the symbol chain. (They are still pointed to by the fixes.) - * - * Count the remaining symbols. - * Assign a symbol number to each symbol. - * Count the number of string-table chars we will emit. - * Put this info into the headers as appropriate. - * - */ + * + * Crawl the symbol chain. + * + * For each symbol whose value depends on a frag, take the address of + * that frag and subsume it into the value of the symbol. + * After this, there is just one way to lookup a symbol value. + * Values are left in their final state for object file emission. + * We adjust the values of 'L' local symbols, even if we do + * not intend to emit them to the object file, because their values + * are needed for fix-ups. + * + * Unless we saw a -L flag, remove all symbols that begin with 'L' + * from the symbol chain. (They are still pointed to by the fixes.) + * + * Count the remaining symbols. + * Assign a symbol number to each symbol. + * Count the number of string-table chars we will emit. + * Put this info into the headers as appropriate. + * + */ know (zero_address_frag.fr_address == 0); string_byte_count = sizeof (string_byte_count); @@ -353,11 +353,11 @@ write_object_file () H_SET_STRING_SIZE (&headers, string_byte_count); /* - * Addresses of frags now reflect addresses we use in the object file. - * Symbol values are correct. - * Scan the frags, converting any ".org"s and ".align"s to ".fill"s. - * Also converting any machine-dependent frags using md_convert_frag(); - */ + * Addresses of frags now reflect addresses we use in the object file. + * Symbol values are correct. + * Scan the frags, converting any ".org"s and ".align"s to ".fill"s. + * Also converting any machine-dependent frags using md_convert_frag(); + */ subseg_change (SEG_TEXT, 0); for (fragP = text_frag_root; fragP; fragP = fragP->fr_next) @@ -387,10 +387,10 @@ write_object_file () know ((fragP->fr_next == NULL) || ((fragP->fr_next->fr_address - fragP->fr_address) == fragP->fr_fix)); /* - * After md_convert_frag, we make the frag into a ".space 0". - * Md_convert_frag() should set up any fixSs and constants - * required. - */ + * After md_convert_frag, we make the frag into a ".space 0". + * Md_convert_frag() should set up any fixSs and constants + * required. + */ frag_wane (fragP); break; @@ -691,10 +691,8 @@ relax_segment (segment_frag_root, segment) /* In case md_estimate_size_before_relax() wants to make fixSs. */ subseg_change (segment, 0); - /* - * For each frag in segment: count and store (a 1st guess of) - * fr_address. - */ + /* For each frag in segment: count and store (a 1st guess of) + fr_address. */ address = 0; for (fragP = segment_frag_root; fragP; fragP = fragP->fr_next) { @@ -712,10 +710,7 @@ relax_segment (segment_frag_root, segment) break; case rs_org: - /* - * Assume .org is nugatory. It will grow with 1st - * relax. - */ + /* Assume .org is nugatory. It will grow with 1st relax. */ break; case rs_machine_dependent: @@ -734,39 +729,34 @@ relax_segment (segment_frag_root, segment) } /* switch(fr_type) */ } /* for each frag in the segment */ - /* - * Do relax(). - */ + /* Do relax(). */ { - register long stretch; /* May be any size, 0 or negative. */ + long stretch; /* May be any size, 0 or negative. */ /* Cumulative number of addresses we have */ /* relaxed this pass. */ /* We may have relaxed more than one address. */ - register long stretched; /* Have we stretched on this pass? */ - /* This is 'cuz stretch may be zero, when, - in fact some piece of code grew, and - another shrank. If a branch instruction - doesn't fit anymore, we could be scrod */ + long stretched; /* Have we stretched on this pass? */ + /* This is 'cuz stretch may be zero, when, in fact some piece of code + grew, and another shrank. If a branch instruction doesn't fit anymore, + we could be scrod. */ do { stretch = stretched = 0; for (fragP = segment_frag_root; fragP; fragP = fragP->fr_next) { - register long growth = 0; - register unsigned long was_address; - /* register long var; */ - register long offset; - register symbolS *symbolP; - register long target; - register long after; - register long aim; + long growth = 0; + unsigned long was_address; + long offset; + symbolS *symbolP; + long target; + long after; + long aim; was_address = fragP->fr_address; address = fragP->fr_address += stretch; symbolP = fragP->fr_symbol; offset = fragP->fr_offset; - /* var = fragP->fr_var; */ switch (fragP->fr_type) { @@ -776,9 +766,9 @@ relax_segment (segment_frag_root, segment) #ifndef WORKING_DOT_WORD /* JF: This is RMS's idea. I do *NOT* want to be blamed - for it I do not want to write it. I do not want to have - anything to do with it. This is not the proper way to - implement this misfeature. */ + for it I do not want to write it. I do not want to have + anything to do with it. This is not the proper way to + implement this misfeature. */ case rs_broken_word: { struct broken_word *lie; @@ -787,9 +777,9 @@ relax_segment (segment_frag_root, segment) extern int md_long_jump_size; /* Yes this is ugly (storing the broken_word pointer - in the symbol slot). Still, this whole chunk of - code is ugly, and I don't feel like doing anything - about it. Think of it as stubbornness in action */ + in the symbol slot). Still, this whole chunk of + code is ugly, and I don't feel like doing anything + about it. Think of it as stubbornness in action. */ growth = 0; for (lie = (struct broken_word *) (fragP->fr_symbol); lie && lie->dispfrag == fragP; @@ -799,8 +789,11 @@ relax_segment (segment_frag_root, segment) if (lie->added) continue; - offset = lie->add->sy_frag->fr_address + S_GET_VALUE (lie->add) + lie->addnum - - (lie->sub->sy_frag->fr_address + S_GET_VALUE (lie->sub)); + offset = (lie->add->sy_frag->fr_address + + S_GET_VALUE (lie->add) + + lie->addnum + - (lie->sub->sy_frag->fr_address + + S_GET_VALUE (lie->sub))); if (offset <= -32768 || offset >= 32767) { if (flagseen['K']) @@ -814,7 +807,9 @@ relax_segment (segment_frag_root, segment) fragP->fr_subtype++; growth += md_short_jump_size; } - for (untruth = lie->next_broken_word; untruth && untruth->dispfrag == lie->dispfrag; untruth = untruth->next_broken_word) + for (untruth = lie->next_broken_word; + untruth && untruth->dispfrag == lie->dispfrag; + untruth = untruth->next_broken_word) if ((untruth->add->sy_frag == lie->add->sy_frag) && S_GET_VALUE (untruth->add) == S_GET_VALUE (lie->add)) { @@ -829,8 +824,8 @@ relax_segment (segment_frag_root, segment) } /* case rs_broken_word */ #endif case rs_align: - growth = relax_align ((relax_addressT) (address + fragP->fr_fix), offset) - - relax_align ((relax_addressT) (was_address + fragP->fr_fix), offset); + growth = (relax_align ((relax_addressT) (address + fragP->fr_fix), offset) + - relax_align ((relax_addressT) (was_address + fragP->fr_fix), offset)); break; case rs_org: @@ -851,21 +846,21 @@ relax_segment (segment_frag_root, segment) know (fragP->fr_next); after = fragP->fr_next->fr_address; growth = ((target - after) > 0) ? (target - after) : 0; - /* Growth may be -ve, but variable part */ - /* of frag cannot have < 0 chars. */ - /* That is, we can't .org backwards. */ + /* Growth may be -ve, but variable part of frag cannot have + fewer than 0 chars. That is, we can't .org backwards. */ growth -= stretch; /* This is an absolute growth factor */ break; case rs_machine_dependent: { - register const relax_typeS *this_type; - register const relax_typeS *start_type; - register relax_substateT next_state; - register relax_substateT this_state; + const relax_typeS *this_type; + const relax_typeS *start_type; + relax_substateT next_state; + relax_substateT this_state; - start_type = this_type = md_relax_table + (this_state = fragP->fr_subtype); + this_state = fragP->fr_subtype; + start_type = this_type = md_relax_table + this_state; target = offset; if (symbolP) @@ -880,47 +875,45 @@ relax_segment (segment_frag_root, segment) + symbolP->sy_frag->fr_address; /* If frag has yet to be reached on this pass, - assume it will move by STRETCH just as we did. - If this is not so, it will be because some frag - between grows, and that will force another pass. */ + assume it will move by STRETCH just as we did. + If this is not so, it will be because some frag + between grows, and that will force another pass. */ /* JF was just address */ /* JF also added is_dnrange hack */ /* There's gotta be a better/faster/etc way - to do this. . . */ + to do this. . . */ /* gnu@cygnus.com: I changed this from > to >= - because I ran into a zero-length frag (fr_fix=0) - which was created when the obstack needed a new - chunk JUST AFTER the opcode of a branch. Since - fr_fix is zero, fr_address of this frag is the same - as fr_address of the next frag. This - zero-length frag was variable and jumped to .+2 - (in the next frag), but since the > comparison - below failed (the two were =, not >), "stretch" - was not added to the target. Stretch was 178, so - the offset appeared to be .-176 instead, which did - not fit into a byte branch, so the assembler - relaxed the branch to a word. This didn't compare - with what happened when the same source file was - assembled on other machines, which is how I found it. - You might want to think about what other places have - trouble with zero length frags... */ + because I ran into a zero-length frag (fr_fix=0) + which was created when the obstack needed a new + chunk JUST AFTER the opcode of a branch. Since + fr_fix is zero, fr_address of this frag is the same + as fr_address of the next frag. This + zero-length frag was variable and jumped to .+2 + (in the next frag), but since the > comparison + below failed (the two were =, not >), "stretch" + was not added to the target. Stretch was 178, so + the offset appeared to be .-176 instead, which did + not fit into a byte branch, so the assembler + relaxed the branch to a word. This didn't compare + with what happened when the same source file was + assembled on other machines, which is how I found it. + You might want to think about what other places have + trouble with zero length frags... */ if (symbolP->sy_frag->fr_address >= was_address && is_dnrange (fragP, symbolP->sy_frag)) { target += stretch; - } /* */ - + } } /* if there's a symbol attached */ aim = target - address - fragP->fr_fix; /* The displacement is affected by the instruction size - * for the 32k architecture. I think we ought to be able - * to add fragP->fr_pcrel_adjust in all cases (it should be - * zero if not used), but just in case it breaks something - * else we'll put this inside #ifdef NS32K ... #endif - */ + for the 32k architecture. I think we ought to be able + to add fragP->fr_pcrel_adjust in all cases (it should be + zero if not used), but just in case it breaks something + else we'll put this inside #ifdef NS32K ... #endif */ #ifdef TC_NS32K aim += fragP->fr_pcrel_adjust; #endif /* TC_NS32K */ @@ -929,52 +922,39 @@ relax_segment (segment_frag_root, segment) { /* Look backwards. */ for (next_state = this_type->rlx_more; next_state;) - { - if (aim >= this_type->rlx_backward) - { - next_state = 0; - } - else - { /* Grow to next state. */ - this_type = md_relax_table + (this_state = next_state); - next_state = this_type->rlx_more; - } - } + if (aim >= this_type->rlx_backward) + next_state = 0; + else + { + /* Grow to next state. */ + this_state = next_state; + this_type = md_relax_table + this_state; + next_state = this_type->rlx_more; + } } else { -#ifdef DONTDEF - /* JF these next few lines of code are for the mc68020 which can't handle short - offsets of zero in branch instructions. What a kludge! */ - if (aim == 0 && this_state == (1 << 2 + 0)) - { /* FOO hard encoded from m.c */ - aim = this_type->rlx_forward + 1; /* Force relaxation into word mode */ - } -#endif #ifdef M68K_AIM_KLUDGE M68K_AIM_KLUDGE (aim, this_state, this_type); #endif - /* JF end of 68020 code */ /* Look forwards. */ for (next_state = this_type->rlx_more; next_state;) - { - if (aim <= this_type->rlx_forward) - { - next_state = 0; - } - else - { /* Grow to next state. */ - this_type = md_relax_table + (this_state = next_state); - next_state = this_type->rlx_more; - } - } + if (aim <= this_type->rlx_forward) + next_state = 0; + else + { + /* Grow to next state. */ + this_state = next_state; + this_type = md_relax_table + this_state; + next_state = this_type->rlx_more; + } } - if ((growth = this_type->rlx_length - start_type->rlx_length) != 0) + growth = this_type->rlx_length - start_type->rlx_length; + if (growth != 0) fragP->fr_subtype = this_state; - - break; - } /* case rs_machine_dependent */ + } + break; default: BAD_CASE (fragP->fr_type); @@ -991,13 +971,13 @@ relax_segment (segment_frag_root, segment) } /* do_relax */ /* - * We now have valid fr_address'es for each frag. - */ + * We now have valid fr_address'es for each frag. + */ /* - * All fr_address's are correct, relative to their own segment. - * We have made all the fixS we will ever make. - */ + * All fr_address's are correct, relative to their own segment. + * We have made all the fixS we will ever make. + */ } /* relax_segment() */ /* |