| /* GAS interface for targets using CGEN: Cpu tools GENerator. |
| Copyright (C) 1996-2024 Free Software Foundation, Inc. |
| |
| This file is part of GAS, the GNU Assembler. |
| |
| GAS 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. |
| |
| GAS 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. |
| |
| You should have received a copy of the GNU General Public License |
| along with GAS; see the file COPYING. If not, write to the Free Software |
| Foundation, 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */ |
| |
| #include "as.h" |
| #include <setjmp.h> |
| #include "symcat.h" |
| #include "cgen-desc.h" |
| #include "subsegs.h" |
| #include "cgen.h" |
| #include "dwarf2dbg.h" |
| |
| #include "symbols.h" |
| |
| #ifdef OBJ_COMPLEX_RELC |
| static expressionS * make_right_shifted_expr |
| (expressionS *, const int, const int); |
| |
| static unsigned long gas_cgen_encode_addend |
| (const unsigned long, const unsigned long, const unsigned long, \ |
| const unsigned long, const unsigned long, const unsigned long, \ |
| const unsigned long); |
| |
| static const char * weak_operand_overflow_check |
| (const expressionS *, const CGEN_OPERAND *); |
| |
| static void queue_fixup_recursively |
| (const int, const int, expressionS *, \ |
| const CGEN_MAYBE_MULTI_IFLD *, const int, const int); |
| |
| static int rightshift = 0; |
| #endif |
| static void queue_fixup (int, int, expressionS *); |
| |
| /* Opcode table descriptor, must be set by md_begin. */ |
| |
| CGEN_CPU_DESC gas_cgen_cpu_desc; |
| |
| /* Callback to insert a register into the symbol table. |
| A target may choose to let GAS parse the registers. |
| ??? Not currently used. */ |
| |
| void |
| cgen_asm_record_register (char *name, int number) |
| { |
| /* Use symbol_create here instead of symbol_new so we don't try to |
| output registers into the object file's symbol table. */ |
| symbol_table_insert (symbol_create (name, reg_section, |
| &zero_address_frag, number)); |
| } |
| |
| /* We need to keep a list of fixups. We can't simply generate them as |
| we go, because that would require us to first create the frag, and |
| that would screw up references to ``.''. |
| |
| This is used by cpu's with simple operands. It keeps knowledge of what |
| an `expressionS' is and what a `fixup' is out of CGEN which for the time |
| being is preferable. |
| |
| OPINDEX is the index in the operand table. |
| OPINFO is something the caller chooses to help in reloc determination. */ |
| |
| struct fixup |
| { |
| int opindex; |
| int opinfo; |
| expressionS exp; |
| struct cgen_maybe_multi_ifield * field; |
| int msb_field_p; |
| }; |
| |
| static struct fixup fixups[GAS_CGEN_MAX_FIXUPS]; |
| static int num_fixups; |
| |
| /* Prepare to parse an instruction. |
| ??? May wish to make this static and delete calls in md_assemble. */ |
| |
| void |
| gas_cgen_init_parse (void) |
| { |
| num_fixups = 0; |
| } |
| |
| /* Queue a fixup. */ |
| |
| static void |
| queue_fixup (int opindex, int opinfo, expressionS *expP) |
| { |
| /* We need to generate a fixup for this expression. */ |
| if (num_fixups >= GAS_CGEN_MAX_FIXUPS) |
| as_fatal (_("too many fixups")); |
| fixups[num_fixups].exp = *expP; |
| fixups[num_fixups].opindex = opindex; |
| fixups[num_fixups].opinfo = opinfo; |
| ++ num_fixups; |
| } |
| |
| /* The following functions allow fixup chains to be stored, retrieved, |
| and swapped. They are a generalization of a pre-existing scheme |
| for storing, restoring and swapping fixup chains that was used by |
| the m32r port. The functionality is essentially the same, only |
| instead of only being able to store a single fixup chain, an entire |
| array of fixup chains can be stored. It is the user's responsibility |
| to keep track of how many fixup chains have been stored and which |
| elements of the array they are in. |
| |
| The algorithms used are the same as in the old scheme. Other than the |
| "array-ness" of the whole thing, the functionality is identical to the |
| old scheme. |
| |
| gas_cgen_initialize_saved_fixups_array(): |
| Sets num_fixups_in_chain to 0 for each element. Call this from |
| md_begin() if you plan to use these functions and you want the |
| fixup count in each element to be set to 0 initially. This is |
| not necessary, but it's included just in case. It performs |
| the same function for each element in the array of fixup chains |
| that gas_init_parse() performs for the current fixups. |
| |
| gas_cgen_save_fixups (element): |
| element - element number of the array you wish to store the fixups |
| to. No mechanism is built in for tracking what element |
| was last stored to. |
| |
| gas_cgen_restore_fixups (element): |
| element - element number of the array you wish to restore the fixups |
| from. |
| |
| gas_cgen_swap_fixups(int element): |
| element - swap the current fixups with those in this element number. |
| */ |
| |
| struct saved_fixups |
| { |
| struct fixup fixup_chain[GAS_CGEN_MAX_FIXUPS]; |
| int num_fixups_in_chain; |
| }; |
| |
| static struct saved_fixups stored_fixups[MAX_SAVED_FIXUP_CHAINS]; |
| |
| void |
| gas_cgen_initialize_saved_fixups_array (void) |
| { |
| int i = 0; |
| |
| while (i < MAX_SAVED_FIXUP_CHAINS) |
| stored_fixups[i++].num_fixups_in_chain = 0; |
| } |
| |
| void |
| gas_cgen_save_fixups (int i) |
| { |
| if (i < 0 || i >= MAX_SAVED_FIXUP_CHAINS) |
| { |
| as_fatal ("index into stored_fixups[] out of bounds"); |
| return; |
| } |
| |
| stored_fixups[i].num_fixups_in_chain = num_fixups; |
| memcpy (stored_fixups[i].fixup_chain, fixups, |
| sizeof (fixups[0]) * num_fixups); |
| num_fixups = 0; |
| } |
| |
| void |
| gas_cgen_restore_fixups (int i) |
| { |
| if (i < 0 || i >= MAX_SAVED_FIXUP_CHAINS) |
| { |
| as_fatal ("index into stored_fixups[] out of bounds"); |
| return; |
| } |
| |
| num_fixups = stored_fixups[i].num_fixups_in_chain; |
| memcpy (fixups, stored_fixups[i].fixup_chain, |
| (sizeof (stored_fixups[i].fixup_chain[0])) * num_fixups); |
| stored_fixups[i].num_fixups_in_chain = 0; |
| } |
| |
| void |
| gas_cgen_swap_fixups (int i) |
| { |
| if (i < 0 || i >= MAX_SAVED_FIXUP_CHAINS) |
| { |
| as_fatal ("index into stored_fixups[] out of bounds"); |
| return; |
| } |
| |
| if (num_fixups == 0) |
| gas_cgen_restore_fixups (i); |
| |
| else if (stored_fixups[i].num_fixups_in_chain == 0) |
| gas_cgen_save_fixups (i); |
| |
| else |
| { |
| int tmp; |
| struct fixup tmp_fixup; |
| |
| tmp = stored_fixups[i].num_fixups_in_chain; |
| stored_fixups[i].num_fixups_in_chain = num_fixups; |
| num_fixups = tmp; |
| |
| for (tmp = GAS_CGEN_MAX_FIXUPS; tmp--;) |
| { |
| tmp_fixup = stored_fixups[i].fixup_chain [tmp]; |
| stored_fixups[i].fixup_chain[tmp] = fixups [tmp]; |
| fixups [tmp] = tmp_fixup; |
| } |
| } |
| } |
| |
| /* Default routine to record a fixup. |
| This is a cover function to fix_new. |
| It exists because we record INSN with the fixup. |
| |
| FRAG and WHERE are their respective arguments to fix_new_exp. |
| LENGTH is in bits. |
| OPINFO is something the caller chooses to help in reloc determination. |
| |
| At this point we do not use a bfd_reloc_code_real_type for |
| operands residing in the insn, but instead just use the |
| operand index. This lets us easily handle fixups for any |
| operand type. We pick a BFD reloc type in md_apply_fix. */ |
| |
| fixS * |
| gas_cgen_record_fixup (fragS *frag, int where, const CGEN_INSN *insn, |
| int length, const CGEN_OPERAND *operand, int opinfo, |
| symbolS *symbol, offsetT offset) |
| { |
| fixS *fixP; |
| |
| /* It may seem strange to use operand->attrs and not insn->attrs here, |
| but it is the operand that has a pc relative relocation. */ |
| fixP = fix_new (frag, where, length / 8, symbol, offset, |
| CGEN_OPERAND_ATTR_VALUE (operand, CGEN_OPERAND_PCREL_ADDR), |
| (bfd_reloc_code_real_type) |
| ((int) BFD_RELOC_UNUSED |
| + (int) operand->type)); |
| fixP->fx_cgen.insn = insn; |
| fixP->fx_cgen.opinfo = opinfo; |
| fixP->fx_cgen.field = NULL; |
| fixP->fx_cgen.msb_field_p = 0; |
| |
| return fixP; |
| } |
| |
| /* Default routine to record a fixup given an expression. |
| This is a cover function to fix_new_exp. |
| It exists because we record INSN with the fixup. |
| |
| FRAG and WHERE are their respective arguments to fix_new_exp. |
| LENGTH is in bits. |
| OPINFO is something the caller chooses to help in reloc determination. |
| |
| At this point we do not use a bfd_reloc_code_real_type for |
| operands residing in the insn, but instead just use the |
| operand index. This lets us easily handle fixups for any |
| operand type. We pick a BFD reloc type in md_apply_fix. */ |
| |
| fixS * |
| gas_cgen_record_fixup_exp (fragS *frag, int where, const CGEN_INSN *insn, |
| int length, const CGEN_OPERAND *operand, int opinfo, |
| expressionS *exp) |
| { |
| fixS *fixP; |
| |
| /* It may seem strange to use operand->attrs and not insn->attrs here, |
| but it is the operand that has a pc relative relocation. */ |
| fixP = fix_new_exp (frag, where, length / 8, exp, |
| CGEN_OPERAND_ATTR_VALUE (operand, CGEN_OPERAND_PCREL_ADDR), |
| (bfd_reloc_code_real_type) |
| ((int) BFD_RELOC_UNUSED |
| + (int) operand->type)); |
| fixP->fx_cgen.insn = insn; |
| fixP->fx_cgen.opinfo = opinfo; |
| fixP->fx_cgen.field = NULL; |
| fixP->fx_cgen.msb_field_p = 0; |
| |
| return fixP; |
| } |
| |
| #ifdef OBJ_COMPLEX_RELC |
| static symbolS * |
| expr_build_binary (operatorT op, symbolS * s1, symbolS * s2) |
| { |
| expressionS e; |
| |
| e.X_op = op; |
| e.X_add_symbol = s1; |
| e.X_op_symbol = s2; |
| e.X_add_number = 0; |
| return make_expr_symbol (& e); |
| } |
| #endif |
| |
| /* Used for communication between the next two procedures. */ |
| static jmp_buf expr_jmp_buf; |
| static int expr_jmp_buf_p; |
| |
| /* Callback for cgen interface. Parse the expression at *STRP. |
| The result is an error message or NULL for success (in which case |
| *STRP is advanced past the parsed text). |
| WANT is an indication of what the caller is looking for. |
| If WANT == CGEN_ASM_PARSE_INIT the caller is beginning to try to match |
| a table entry with the insn, reset the queued fixups counter. |
| An enum cgen_parse_operand_result is stored in RESULTP. |
| OPINDEX is the operand's table entry index. |
| OPINFO is something the caller chooses to help in reloc determination. |
| The resulting value is stored in VALUEP. */ |
| |
| const char * |
| gas_cgen_parse_operand (CGEN_CPU_DESC cd ATTRIBUTE_UNUSED, |
| enum cgen_parse_operand_type want, const char **strP, |
| int opindex, int opinfo, |
| enum cgen_parse_operand_result *resultP, |
| bfd_vma *valueP) |
| { |
| #ifdef __STDC__ |
| /* These are volatile to survive the setjmp. */ |
| char * volatile hold; |
| enum cgen_parse_operand_result * volatile resultP_1; |
| volatile int opinfo_1; |
| #else |
| static char *hold; |
| static enum cgen_parse_operand_result *resultP_1; |
| int opinfo_1; |
| #endif |
| const char *errmsg; |
| expressionS exp; |
| |
| #ifdef OBJ_COMPLEX_RELC |
| volatile int signed_p = 0; |
| symbolS * stmp = NULL; |
| bfd_reloc_code_real_type reloc_type; |
| const CGEN_OPERAND * operand; |
| fixS dummy_fixup; |
| #endif |
| if (want == CGEN_PARSE_OPERAND_INIT) |
| { |
| gas_cgen_init_parse (); |
| return NULL; |
| } |
| |
| resultP_1 = resultP; |
| hold = input_line_pointer; |
| input_line_pointer = (char *) *strP; |
| opinfo_1 = opinfo; |
| |
| /* We rely on md_operand to longjmp back to us. |
| This is done via gas_cgen_md_operand. */ |
| if (setjmp (expr_jmp_buf) != 0) |
| { |
| expr_jmp_buf_p = 0; |
| input_line_pointer = (char *) hold; |
| *resultP_1 = CGEN_PARSE_OPERAND_RESULT_ERROR; |
| return _("illegal operand"); |
| } |
| |
| expr_jmp_buf_p = 1; |
| expression (&exp); |
| expr_jmp_buf_p = 0; |
| errmsg = NULL; |
| |
| *strP = input_line_pointer; |
| input_line_pointer = hold; |
| |
| #ifdef TC_CGEN_PARSE_FIX_EXP |
| opinfo_1 = TC_CGEN_PARSE_FIX_EXP (opinfo_1, & exp); |
| #endif |
| |
| /* FIXME: Need to check `want'. */ |
| |
| resolve_register (&exp); |
| |
| switch (exp.X_op) |
| { |
| case O_illegal: |
| errmsg = _("illegal operand"); |
| *resultP = CGEN_PARSE_OPERAND_RESULT_ERROR; |
| break; |
| case O_absent: |
| errmsg = _("missing operand"); |
| *resultP = CGEN_PARSE_OPERAND_RESULT_ERROR; |
| break; |
| case O_constant: |
| if (want == CGEN_PARSE_OPERAND_SYMBOLIC) |
| goto de_fault; |
| *valueP = exp.X_add_number; |
| *resultP = CGEN_PARSE_OPERAND_RESULT_NUMBER; |
| break; |
| case O_register: |
| *valueP = exp.X_add_number; |
| *resultP = CGEN_PARSE_OPERAND_RESULT_REGISTER; |
| break; |
| de_fault: |
| default: |
| #ifdef OBJ_COMPLEX_RELC |
| /* Look up operand, check to see if there's an obvious |
| overflow (this helps disambiguate some insn parses). */ |
| operand = cgen_operand_lookup_by_num (cd, opindex); |
| errmsg = weak_operand_overflow_check (& exp, operand); |
| |
| if (! errmsg) |
| { |
| asymbol *bsym; |
| |
| /* Fragment the expression as necessary, and queue a reloc. */ |
| memset (& dummy_fixup, 0, sizeof (fixS)); |
| |
| reloc_type = md_cgen_lookup_reloc (0, operand, & dummy_fixup); |
| |
| if (exp.X_op == O_symbol |
| && reloc_type == BFD_RELOC_RELC |
| && symbol_constant_p (exp.X_add_symbol) |
| && (!symbol_symbolS (exp.X_add_symbol) |
| || (bsym = symbol_get_bfdsym (exp.X_add_symbol)) == NULL |
| || (bsym->section != expr_section |
| && bsym->section != absolute_section |
| && bsym->section != undefined_section))) |
| { |
| /* Local labels will have been (eagerly) turned into constants |
| by now, due to the inappropriately deep insight of the |
| expression parser. Unfortunately make_expr_symbol |
| prematurely dives into the symbol evaluator, and in this |
| case it gets a bad answer, so we manually create the |
| expression symbol we want here. */ |
| stmp = symbol_create (FAKE_LABEL_NAME, expr_section, |
| &zero_address_frag, 0); |
| symbol_set_value_expression (stmp, & exp); |
| } |
| else |
| stmp = make_expr_symbol (& exp); |
| |
| /* If this is a pc-relative RELC operand, we |
| need to subtract "." from the expression. */ |
| if (reloc_type == BFD_RELOC_RELC |
| && CGEN_OPERAND_ATTR_VALUE (operand, CGEN_OPERAND_PCREL_ADDR)) |
| stmp = expr_build_binary (O_subtract, stmp, expr_build_dot ()); |
| |
| /* FIXME: this is not a perfect heuristic for figuring out |
| whether an operand is signed: it only works when the operand |
| is an immediate. it's not terribly likely that any other |
| values will be signed relocs, but it's possible. */ |
| if (operand && (operand->hw_type == HW_H_SINT)) |
| signed_p = 1; |
| |
| if (symbol_symbolS (stmp) |
| && (bsym = symbol_get_bfdsym (stmp)) != NULL |
| && bsym->section == expr_section |
| && ! S_IS_LOCAL (stmp)) |
| { |
| if (signed_p) |
| bsym->flags |= BSF_SRELC; |
| else |
| bsym->flags |= BSF_RELC; |
| } |
| |
| /* Now package it all up for the fixup emitter. */ |
| exp.X_op = O_symbol; |
| exp.X_op_symbol = 0; |
| exp.X_add_symbol = stmp; |
| exp.X_add_number = 0; |
| |
| /* Re-init rightshift quantity, just in case. */ |
| rightshift = operand->length; |
| queue_fixup_recursively (opindex, opinfo_1, & exp, |
| (reloc_type == BFD_RELOC_RELC) ? |
| & (operand->index_fields) : 0, |
| signed_p, -1); |
| } |
| * resultP = errmsg |
| ? CGEN_PARSE_OPERAND_RESULT_ERROR |
| : CGEN_PARSE_OPERAND_RESULT_QUEUED; |
| *valueP = 0; |
| #else |
| queue_fixup (opindex, opinfo_1, &exp); |
| *valueP = 0; |
| *resultP = CGEN_PARSE_OPERAND_RESULT_QUEUED; |
| #endif |
| break; |
| } |
| |
| return errmsg; |
| } |
| |
| /* md_operand handler to catch unrecognized expressions and halt the |
| parsing process so the next entry can be tried. |
| |
| ??? This could be done differently by adding code to `expression'. */ |
| |
| void |
| gas_cgen_md_operand (expressionS *expressionP ATTRIBUTE_UNUSED) |
| { |
| /* Don't longjmp if we're not called from within cgen_parse_operand(). */ |
| if (expr_jmp_buf_p) |
| longjmp (expr_jmp_buf, 1); |
| } |
| |
| /* Finish assembling instruction INSN. |
| BUF contains what we've built up so far. |
| LENGTH is the size of the insn in bits. |
| RELAX_P is non-zero if relaxable insns should be emitted as such. |
| Otherwise they're emitted in non-relaxable forms. |
| The "result" is stored in RESULT if non-NULL. */ |
| |
| void |
| gas_cgen_finish_insn (const CGEN_INSN *insn, CGEN_INSN_BYTES_PTR buf, |
| unsigned int length, int relax_p, finished_insnS *result) |
| { |
| int i; |
| int relax_operand; |
| char *f; |
| unsigned int byte_len = length / 8; |
| |
| /* ??? Target foo issues various warnings here, so one might want to provide |
| a hook here. However, our caller is defined in tc-foo.c so there |
| shouldn't be a need for a hook. */ |
| |
| /* Write out the instruction. |
| It is important to fetch enough space in one call to `frag_more'. |
| We use (f - frag_now->fr_literal) to compute where we are and we |
| don't want frag_now to change between calls. |
| |
| Relaxable instructions: We need to ensure we allocate enough |
| space for the largest insn. */ |
| |
| if (CGEN_INSN_ATTR_VALUE (insn, CGEN_INSN_RELAXED)) |
| /* These currently shouldn't get here. */ |
| abort (); |
| |
| /* Is there a relaxable insn with the relaxable operand needing a fixup? */ |
| |
| relax_operand = -1; |
| if (relax_p && CGEN_INSN_ATTR_VALUE (insn, CGEN_INSN_RELAXABLE)) |
| { |
| /* Scan the fixups for the operand affected by relaxing |
| (i.e. the branch address). */ |
| |
| for (i = 0; i < num_fixups; ++i) |
| { |
| if (CGEN_OPERAND_ATTR_VALUE (cgen_operand_lookup_by_num (gas_cgen_cpu_desc, fixups[i].opindex), |
| CGEN_OPERAND_RELAX)) |
| { |
| relax_operand = i; |
| break; |
| } |
| } |
| } |
| |
| if (relax_operand != -1) |
| { |
| int max_len; |
| fragS *old_frag; |
| expressionS *exp; |
| symbolS *sym; |
| offsetT off; |
| |
| #ifdef TC_CGEN_MAX_RELAX |
| max_len = TC_CGEN_MAX_RELAX (insn, byte_len); |
| #else |
| max_len = CGEN_MAX_INSN_SIZE; |
| #endif |
| /* Ensure variable part and fixed part are in same fragment. */ |
| /* FIXME: Having to do this seems like a hack. */ |
| frag_grow (max_len); |
| |
| /* Allocate space for the fixed part. */ |
| f = frag_more (byte_len); |
| |
| /* Create a relaxable fragment for this instruction. */ |
| old_frag = frag_now; |
| |
| exp = &fixups[relax_operand].exp; |
| sym = exp->X_add_symbol; |
| off = exp->X_add_number; |
| if (exp->X_op != O_constant && exp->X_op != O_symbol) |
| { |
| /* Handle complex expressions. */ |
| sym = make_expr_symbol (exp); |
| off = 0; |
| } |
| |
| frag_var (rs_machine_dependent, |
| max_len - byte_len /* max chars */, |
| 0 /* variable part already allocated */, |
| /* FIXME: When we machine generate the relax table, |
| machine generate a macro to compute subtype. */ |
| 1 /* subtype */, |
| sym, |
| off, |
| f); |
| |
| /* Record the operand number with the fragment so md_convert_frag |
| can use gas_cgen_md_record_fixup to record the appropriate reloc. */ |
| old_frag->fr_cgen.insn = insn; |
| old_frag->fr_cgen.opindex = fixups[relax_operand].opindex; |
| old_frag->fr_cgen.opinfo = fixups[relax_operand].opinfo; |
| if (result) |
| result->frag = old_frag; |
| } |
| else |
| { |
| f = frag_more (byte_len); |
| if (result) |
| result->frag = frag_now; |
| } |
| |
| /* If we're recording insns as numbers (rather than a string of bytes), |
| target byte order handling is deferred until now. */ |
| #if CGEN_INT_INSN_P |
| cgen_put_insn_value (gas_cgen_cpu_desc, (unsigned char *) f, length, *buf, |
| gas_cgen_cpu_desc->insn_endian); |
| #else |
| memcpy (f, buf, byte_len); |
| #endif |
| |
| /* Emit DWARF2 debugging information. */ |
| dwarf2_emit_insn (byte_len); |
| |
| /* Create any fixups. */ |
| for (i = 0; i < num_fixups; ++i) |
| { |
| fixS *fixP; |
| const CGEN_OPERAND *operand = |
| cgen_operand_lookup_by_num (gas_cgen_cpu_desc, fixups[i].opindex); |
| |
| /* Don't create fixups for these. That's done during relaxation. |
| We don't need to test for CGEN_INSN_RELAXED as they can't get here |
| (see above). */ |
| if (relax_p |
| && CGEN_INSN_ATTR_VALUE (insn, CGEN_INSN_RELAXABLE) |
| && CGEN_OPERAND_ATTR_VALUE (operand, CGEN_OPERAND_RELAX)) |
| continue; |
| |
| #ifndef md_cgen_record_fixup_exp |
| #define md_cgen_record_fixup_exp gas_cgen_record_fixup_exp |
| #endif |
| |
| fixP = md_cgen_record_fixup_exp (frag_now, f - frag_now->fr_literal, |
| insn, length, operand, |
| fixups[i].opinfo, |
| &fixups[i].exp); |
| fixP->fx_cgen.field = fixups[i].field; |
| fixP->fx_cgen.msb_field_p = fixups[i].msb_field_p; |
| if (result) |
| result->fixups[i] = fixP; |
| } |
| |
| if (result) |
| { |
| result->num_fixups = num_fixups; |
| result->addr = f; |
| } |
| } |
| |
| #ifdef OBJ_COMPLEX_RELC |
| /* Queue many fixups, recursively. If the field is a multi-ifield, |
| repeatedly queue its sub-parts, right shifted to fit into the field (we |
| assume here multi-fields represent a left-to-right, MSB0-LSB0 |
| reading). */ |
| |
| static void |
| queue_fixup_recursively (const int opindex, |
| const int opinfo, |
| expressionS * expP, |
| const CGEN_MAYBE_MULTI_IFLD * field, |
| const int signed_p, |
| const int part_of_multi) |
| { |
| if (field && field->count) |
| { |
| int i; |
| |
| for (i = 0; i < field->count; ++ i) |
| queue_fixup_recursively (opindex, opinfo, expP, |
| & (field->val.multi[i]), signed_p, i); |
| } |
| else |
| { |
| expressionS * new_exp = expP; |
| |
| #ifdef DEBUG |
| printf ("queueing fixup for field %s\n", |
| (field ? field->val.leaf->name : "??")); |
| print_symbol_value (expP->X_add_symbol); |
| #endif |
| if (field && part_of_multi != -1) |
| { |
| rightshift -= field->val.leaf->length; |
| |
| /* Shift reloc value by number of bits remaining after this |
| field. */ |
| if (rightshift) |
| new_exp = make_right_shifted_expr (expP, rightshift, signed_p); |
| } |
| |
| /* Truncate reloc values to length, *after* leftmost one. */ |
| fixups[num_fixups].msb_field_p = (part_of_multi <= 0); |
| fixups[num_fixups].field = (CGEN_MAYBE_MULTI_IFLD *) field; |
| |
| queue_fixup (opindex, opinfo, new_exp); |
| } |
| } |
| |
| /* Encode the self-describing RELC reloc format's addend. */ |
| |
| static unsigned long |
| gas_cgen_encode_addend (const unsigned long start, /* in bits */ |
| const unsigned long len, /* in bits */ |
| const unsigned long oplen, /* in bits */ |
| const unsigned long wordsz, /* in bytes */ |
| const unsigned long chunksz, /* in bytes */ |
| const unsigned long signed_p, |
| const unsigned long trunc_p) |
| { |
| unsigned long res = 0L; |
| |
| res |= start & 0x3F; |
| res |= (oplen & 0x3F) << 6; |
| res |= (len & 0x3F) << 12; |
| res |= (wordsz & 0xF) << 18; |
| res |= (chunksz & 0xF) << 22; |
| res |= (CGEN_INSN_LSB0_P ? 1 : 0) << 27; |
| res |= signed_p << 28; |
| res |= trunc_p << 29; |
| |
| return res; |
| } |
| |
| /* Purpose: make a weak check that the expression doesn't overflow the |
| operand it's to be inserted into. |
| |
| Rationale: some insns used to use %operators to disambiguate during a |
| parse. when these %operators are translated to expressions by the macro |
| expander, the ambiguity returns. we attempt to disambiguate by field |
| size. |
| |
| Method: check to see if the expression's top node is an O_and operator, |
| and the mask is larger than the operand length. This would be an |
| overflow, so signal it by returning an error string. Any other case is |
| ambiguous, so we assume it's OK and return NULL. */ |
| |
| static const char * |
| weak_operand_overflow_check (const expressionS * exp, |
| const CGEN_OPERAND * operand) |
| { |
| const unsigned long len = operand->length; |
| unsigned long mask; |
| unsigned long opmask = len == 0 ? 0 : (1UL << (len - 1) << 1) - 1; |
| |
| if (!exp) |
| return NULL; |
| |
| if (exp->X_op != O_bit_and) |
| { |
| /* Check for implicit overflow flag. */ |
| if (CGEN_OPERAND_ATTR_VALUE |
| (operand, CGEN_OPERAND_RELOC_IMPLIES_OVERFLOW)) |
| return _("a reloc on this operand implies an overflow"); |
| return NULL; |
| } |
| |
| mask = exp->X_add_number; |
| |
| if (exp->X_add_symbol |
| && symbol_constant_p (exp->X_add_symbol)) |
| mask |= *symbol_X_add_number (exp->X_add_symbol); |
| |
| if (exp->X_op_symbol |
| && symbol_constant_p (exp->X_op_symbol)) |
| mask |= *symbol_X_add_number (exp->X_op_symbol); |
| |
| /* Want to know if mask covers more bits than opmask. |
| this is the same as asking if mask has any bits not in opmask, |
| or whether (mask & ~opmask) is nonzero. */ |
| if (mask && (mask & ~opmask)) |
| { |
| #ifdef DEBUG |
| printf ("overflow: (mask = %8.8x, ~opmask = %8.8x, AND = %8.8x)\n", |
| mask, ~opmask, (mask & ~opmask)); |
| #endif |
| return _("operand mask overflow"); |
| } |
| |
| return NULL; |
| } |
| |
| static expressionS * |
| make_right_shifted_expr (expressionS * exp, |
| const int amount, |
| const int signed_p) |
| { |
| symbolS * stmp = 0; |
| expressionS * new_exp; |
| asymbol *bsym; |
| |
| stmp = expr_build_binary (O_right_shift, |
| make_expr_symbol (exp), |
| expr_build_uconstant (amount)); |
| bsym = symbol_get_bfdsym (stmp); |
| |
| if (signed_p) |
| bsym->flags |= BSF_SRELC; |
| else |
| bsym->flags |= BSF_RELC; |
| |
| /* Then wrap that in a "symbol expr" for good measure. */ |
| new_exp = XNEW (expressionS); |
| memset (new_exp, 0, sizeof (expressionS)); |
| new_exp->X_op = O_symbol; |
| new_exp->X_op_symbol = 0; |
| new_exp->X_add_symbol = stmp; |
| new_exp->X_add_number = 0; |
| |
| return new_exp; |
| } |
| |
| #endif |
| |
| /* Apply a fixup to the object code. This is called for all the |
| fixups we generated by the call to fix_new_exp, above. In the call |
| above we used a reloc code which was the largest legal reloc code |
| plus the operand index. Here we undo that to recover the operand |
| index. At this point all symbol values should be fully resolved, |
| and we attempt to completely resolve the reloc. If we can not do |
| that, we determine the correct reloc code and put it back in the fixup. */ |
| |
| /* FIXME: This function handles some of the fixups and bfd_install_relocation |
| handles the rest. bfd_install_relocation (or some other bfd function) |
| should handle them all. */ |
| |
| void |
| gas_cgen_md_apply_fix (fixS *fixP, valueT *valP, segT seg ATTRIBUTE_UNUSED) |
| { |
| char *where = fixP->fx_frag->fr_literal + fixP->fx_where; |
| valueT value = * valP; |
| /* Canonical name, since used a lot. */ |
| CGEN_CPU_DESC cd = gas_cgen_cpu_desc; |
| |
| if (fixP->fx_addsy == (symbolS *) NULL) |
| fixP->fx_done = 1; |
| |
| /* We don't actually support subtracting a symbol. */ |
| if (fixP->fx_subsy != (symbolS *) NULL) |
| as_bad_where (fixP->fx_file, fixP->fx_line, _("expression too complex")); |
| |
| if ((int) fixP->fx_r_type >= (int) BFD_RELOC_UNUSED) |
| { |
| int opindex = (int) fixP->fx_r_type - (int) BFD_RELOC_UNUSED; |
| const CGEN_OPERAND *operand = cgen_operand_lookup_by_num (cd, opindex); |
| const char *errmsg; |
| bfd_reloc_code_real_type reloc_type; |
| const CGEN_INSN *insn = fixP->fx_cgen.insn; |
| #ifdef OBJ_COMPLEX_RELC |
| int start; |
| int length; |
| int signed_p = 0; |
| |
| if (fixP->fx_cgen.field) |
| { |
| /* Use the twisty little pointer path |
| back to the ifield if it exists. */ |
| start = fixP->fx_cgen.field->val.leaf->start; |
| length = fixP->fx_cgen.field->val.leaf->length; |
| } |
| else |
| { |
| /* Or the far less useful operand-size guesstimate. */ |
| start = operand->start; |
| length = operand->length; |
| } |
| |
| /* FIXME: this is not a perfect heuristic for figuring out |
| whether an operand is signed: it only works when the operand |
| is an immediate. it's not terribly likely that any other |
| values will be signed relocs, but it's possible. */ |
| if (operand && (operand->hw_type == HW_H_SINT)) |
| signed_p = 1; |
| #endif |
| |
| /* If the reloc has been fully resolved finish the operand here. */ |
| /* FIXME: This duplicates the capabilities of code in BFD. */ |
| if (fixP->fx_done |
| /* FIXME: If partial_inplace isn't set bfd_install_relocation won't |
| finish the job. Testing for pcrel is a temporary hack. */ |
| || fixP->fx_pcrel) |
| { |
| CGEN_FIELDS *fields = xmalloc (CGEN_CPU_SIZEOF_FIELDS (cd)); |
| |
| CGEN_CPU_SET_FIELDS_BITSIZE (cd) (fields, CGEN_INSN_BITSIZE (insn)); |
| CGEN_CPU_SET_VMA_OPERAND (cd) (cd, opindex, fields, (bfd_vma) value); |
| |
| #if CGEN_INT_INSN_P |
| { |
| CGEN_INSN_INT insn_value = |
| cgen_get_insn_value (cd, (unsigned char *) where, |
| CGEN_INSN_BITSIZE (insn), |
| cd->insn_endian); |
| |
| /* ??? 0 is passed for `pc'. */ |
| errmsg = CGEN_CPU_INSERT_OPERAND (cd) (cd, opindex, fields, |
| &insn_value, (bfd_vma) 0); |
| cgen_put_insn_value (cd, (unsigned char *) where, |
| CGEN_INSN_BITSIZE (insn), insn_value, |
| cd->insn_endian); |
| } |
| #else |
| /* ??? 0 is passed for `pc'. */ |
| errmsg = CGEN_CPU_INSERT_OPERAND (cd) (cd, opindex, fields, |
| (unsigned char *) where, |
| (bfd_vma) 0); |
| #endif |
| if (errmsg) |
| as_bad_where (fixP->fx_file, fixP->fx_line, "%s", errmsg); |
| |
| free (fields); |
| } |
| |
| if (fixP->fx_done) |
| return; |
| |
| /* The operand isn't fully resolved. Determine a BFD reloc value |
| based on the operand information and leave it to |
| bfd_install_relocation. Note that this doesn't work when |
| partial_inplace == false. */ |
| |
| reloc_type = md_cgen_lookup_reloc (insn, operand, fixP); |
| #ifdef OBJ_COMPLEX_RELC |
| if (reloc_type == BFD_RELOC_RELC) |
| { |
| /* Change addend to "self-describing" form, |
| for BFD to handle in the linker. */ |
| value = gas_cgen_encode_addend (start, operand->length, |
| length, fixP->fx_size, |
| cd->insn_chunk_bitsize / 8, |
| signed_p, |
| ! (fixP->fx_cgen.msb_field_p)); |
| } |
| #endif |
| |
| if (reloc_type != BFD_RELOC_NONE) |
| fixP->fx_r_type = reloc_type; |
| else |
| { |
| as_bad_where (fixP->fx_file, fixP->fx_line, |
| _("unresolved expression that must be resolved")); |
| fixP->fx_done = 1; |
| return; |
| } |
| } |
| else if (fixP->fx_done) |
| { |
| /* We're finished with this fixup. Install it because |
| bfd_install_relocation won't be called to do it. */ |
| switch (fixP->fx_r_type) |
| { |
| case BFD_RELOC_8: |
| md_number_to_chars (where, value, 1); |
| break; |
| case BFD_RELOC_16: |
| md_number_to_chars (where, value, 2); |
| break; |
| case BFD_RELOC_32: |
| md_number_to_chars (where, value, 4); |
| break; |
| case BFD_RELOC_64: |
| md_number_to_chars (where, value, 8); |
| break; |
| default: |
| as_bad_where (fixP->fx_file, fixP->fx_line, |
| _("internal error: can't install fix for reloc type %d (`%s')"), |
| fixP->fx_r_type, bfd_get_reloc_code_name (fixP->fx_r_type)); |
| break; |
| } |
| } |
| /* else |
| bfd_install_relocation will be called to finish things up. */ |
| |
| /* Tuck `value' away for use by tc_gen_reloc. |
| See the comment describing fx_addnumber in write.h. |
| This field is misnamed (or misused :-). */ |
| fixP->fx_addnumber = value; |
| } |
| |
| bfd_reloc_code_real_type |
| gas_cgen_pcrel_r_type (bfd_reloc_code_real_type r) |
| { |
| switch (r) |
| { |
| case BFD_RELOC_8: r = BFD_RELOC_8_PCREL; break; |
| case BFD_RELOC_16: r = BFD_RELOC_16_PCREL; break; |
| case BFD_RELOC_24: r = BFD_RELOC_24_PCREL; break; |
| case BFD_RELOC_32: r = BFD_RELOC_32_PCREL; break; |
| case BFD_RELOC_64: r = BFD_RELOC_64_PCREL; break; |
| default: |
| break; |
| } |
| return r; |
| } |
| |
| /* Translate internal representation of relocation info to BFD target format. |
| |
| FIXME: To what extent can we get all relevant targets to use this? */ |
| |
| arelent * |
| gas_cgen_tc_gen_reloc (asection *section ATTRIBUTE_UNUSED, fixS *fixP) |
| { |
| bfd_reloc_code_real_type r_type = fixP->fx_r_type; |
| arelent *reloc; |
| |
| reloc = XNEW (arelent); |
| |
| #ifdef GAS_CGEN_PCREL_R_TYPE |
| if (fixP->fx_pcrel) |
| r_type = GAS_CGEN_PCREL_R_TYPE (r_type); |
| #endif |
| reloc->howto = bfd_reloc_type_lookup (stdoutput, r_type); |
| |
| if (reloc->howto == (reloc_howto_type *) NULL) |
| { |
| as_bad_where (fixP->fx_file, fixP->fx_line, |
| _("relocation is not supported")); |
| return NULL; |
| } |
| |
| gas_assert (!fixP->fx_pcrel == !reloc->howto->pc_relative); |
| |
| reloc->sym_ptr_ptr = XNEW (asymbol *); |
| *reloc->sym_ptr_ptr = symbol_get_bfdsym (fixP->fx_addsy); |
| |
| /* Use fx_offset for these cases. */ |
| if (fixP->fx_r_type == BFD_RELOC_VTABLE_ENTRY |
| || fixP->fx_r_type == BFD_RELOC_VTABLE_INHERIT) |
| reloc->addend = fixP->fx_offset; |
| else |
| reloc->addend = fixP->fx_addnumber; |
| |
| reloc->address = fixP->fx_frag->fr_address + fixP->fx_where; |
| return reloc; |
| } |
| |
| /* Perform any cgen specific initialisation. |
| Called after gas_cgen_cpu_desc has been created. */ |
| |
| void |
| gas_cgen_begin (void) |
| { |
| if (flag_signed_overflow_ok) |
| cgen_set_signed_overflow_ok (gas_cgen_cpu_desc); |
| else |
| cgen_clear_signed_overflow_ok (gas_cgen_cpu_desc); |
| } |