From 7ed4c4c5d0100ac29e959ab0fa86fb01607398b1 Mon Sep 17 00:00:00 2001 From: Nick Clifton Date: Tue, 5 Oct 2004 13:51:40 +0000 Subject: [PATCH] Add support for generating ARM unwind tables. --- gas/ChangeLog | 21 + gas/NEWS | 2 + gas/config/tc-arm.c | 1429 ++++++++++++++++++++++++++++---- gas/doc/c-arm.texi | 98 +++ gas/testsuite/gas/arm/arm.exp | 3 +- gas/testsuite/gas/arm/unwind.d | 33 + gas/testsuite/gas/arm/unwind.s | 46 + 7 files changed, 1457 insertions(+), 175 deletions(-) create mode 100644 gas/testsuite/gas/arm/unwind.d create mode 100644 gas/testsuite/gas/arm/unwind.s diff --git a/gas/ChangeLog b/gas/ChangeLog index 5fdaa9bfce..dbd128ae01 100644 --- a/gas/ChangeLog +++ b/gas/ChangeLog @@ -1,3 +1,24 @@ +2004-10-05 Paul Brook + + * config/tc-arm.c (unwind): New variable. + (vfp_sp_encode_reg): New function. + (vfp_sp_reg_required_here): Use it. + (vfp_sp_reg_list, vfp_dp_reg_list): Remove. + (vfp_parse_reg_list): New function. + (s_arm_unwind_fnstart, s_arm_unwind_fnend, s_arm_unwind_cantunwind, + s_arm_unwind_personality, s_arm_unwind_personalityindex, + s_arm_unwind_handlerdata, s_arm_unwind_save, s_arm_unwind_movsp, + s_arm_unwind_pad, s_arm_unwind_setfp, s_arm_unwind_raw): New + functions. + (md_pseudo_table): Add them. + (do_vfp_reg2_from_sp2): Use vfp_parse_reg_list and vfp_sp_encode_reg. + (do_vfp_sp2_from_reg2, vfp_sp_ldstm, vfp_dp_ldstm): Ditto. + (set_section, add_unwind_adjustsp, flush_pending_unwind, + finish_unwind_opcodes, start_unwind_section, create_unwind_entry, + require_hashconst, add_unwind_opcode): New functions. + * doc/tc-arm.text: Document unwinding opcodes. + * NEWS: Mention the new feature. + 2004-10-04 Eric Christopher * config/tc-mips.c (md_apply_fix3): Remove erroneous assert. diff --git a/gas/NEWS b/gas/NEWS index 5a6b42b3ef..fb487c22f3 100644 --- a/gas/NEWS +++ b/gas/NEWS @@ -1,5 +1,7 @@ -*- text -*- +* Added support for generating unwind tables for ARM ELF targets. + * Add a -g command line option to generate debug information in the target's preferred debug format. diff --git a/gas/config/tc-arm.c b/gas/config/tc-arm.c index 9770ccd119..e17b037ecb 100644 --- a/gas/config/tc-arm.c +++ b/gas/config/tc-arm.c @@ -43,9 +43,46 @@ #include "dwarf2dbg.h" #endif -/* XXX Set this to 1 after the next binutils release */ +/* XXX Set this to 1 after the next binutils release. */ #define WARN_DEPRECATED 0 +#ifdef OBJ_ELF +/* Must be at least the size of the largest unwind opcode (currently two). */ +#define ARM_OPCODE_CHUNK_SIZE 8 + +/* This structure holds the unwinding state. */ + +static struct +{ + symbolS * proc_start; + symbolS * table_entry; + symbolS * personality_routine; + int personality_index; + /* The segment containing the function. */ + segT saved_seg; + subsegT saved_subseg; + /* Opcodes generated from this function. */ + unsigned char * opcodes; + int opcode_count; + int opcode_alloc; + /* The number of bytes pushed to the stack. */ + offsetT frame_size; + /* We don't add stack adjustment opcodes immediately so that we can merge + multiple adjustments. We can also omit the final adjustment + when using a frame pointer. */ + offsetT pending_offset; + /* These two fields are set by both unwind_movsp and unwind_setfp. They + hold the reg+offset to use when restoring sp from a frame pointer. */ + offsetT fp_offset; + int fp_reg; + /* Nonzero if an unwind_setfp directive has been seen. */ + unsigned fp_used:1; + /* Nonzero if the last opcode restores sp from fp_reg. */ + unsigned sp_restored:1; +} unwind; + +#endif /* OBJ_ELF */ + enum arm_float_abi { ARM_FLOAT_ABI_HARD, @@ -7270,32 +7307,40 @@ do_fpa_to_reg (char * str) end_of_line (str); } +/* Encode a VFP SP register number. */ + +static void +vfp_sp_encode_reg (int reg, enum vfp_sp_reg_pos pos) +{ + switch (pos) + { + case VFP_REG_Sd: + inst.instruction |= ((reg >> 1) << 12) | ((reg & 1) << 22); + break; + + case VFP_REG_Sn: + inst.instruction |= ((reg >> 1) << 16) | ((reg & 1) << 7); + break; + + case VFP_REG_Sm: + inst.instruction |= ((reg >> 1) << 0) | ((reg & 1) << 5); + break; + + default: + abort (); + } +} + static int vfp_sp_reg_required_here (char ** str, enum vfp_sp_reg_pos pos) { int reg; - char *start = *str; + char * start = *str; if ((reg = arm_reg_parse (str, all_reg_maps[REG_TYPE_SN].htab)) != FAIL) { - switch (pos) - { - case VFP_REG_Sd: - inst.instruction |= ((reg >> 1) << 12) | ((reg & 1) << 22); - break; - - case VFP_REG_Sn: - inst.instruction |= ((reg >> 1) << 16) | ((reg & 1) << 7); - break; - - case VFP_REG_Sm: - inst.instruction |= ((reg >> 1) << 0) | ((reg & 1) << 5); - break; - - default: - abort (); - } + vfp_sp_encode_reg (reg, pos); return reg; } @@ -7445,21 +7490,21 @@ do_vfp_reg_from_sp (char * str) end_of_line (str); } -/* Parse and encode a VFP SP register list, storing the initial - register in position POS and returning the range as the result. If - the string is invalid return FAIL (an invalid range). */ +/* Parse a VFP register list. If the string is invalid return FAIL. + Otherwise return the number of registers, and set PBASE to the first + register. Double precision registers are matched if DP is nonzero. */ -static long -vfp_sp_reg_list (char ** str, enum vfp_sp_reg_pos pos) +static int +vfp_parse_reg_list (char **str, int *pbase, int dp) { - long range = 0; - int base_reg = 0; + int base_reg; int new_base; - long base_bits = 0; + int regtype; + int max_regs; int count = 0; - long tempinst; - unsigned long mask = 0; int warned = 0; + unsigned long mask = 0; + int i; if (**str != '{') return FAIL; @@ -7467,21 +7512,31 @@ vfp_sp_reg_list (char ** str, enum vfp_sp_reg_pos pos) (*str)++; skip_whitespace (*str); - tempinst = inst.instruction; + if (dp) + { + regtype = REG_TYPE_DN; + max_regs = 16; + } + else + { + regtype = REG_TYPE_SN; + max_regs = 32; + } + + base_reg = max_regs; do { - inst.instruction = 0; - - if ((new_base = vfp_sp_reg_required_here (str, pos)) == FAIL) - return FAIL; - - if (count == 0 || base_reg > new_base) + new_base = arm_reg_parse (str, all_reg_maps[regtype].htab); + if (new_base == FAIL) { - base_reg = new_base; - base_bits = inst.instruction; + inst.error = _(all_reg_maps[regtype].expected); + return FAIL; } + if (new_base < base_reg) + base_reg = new_base; + if (mask & (1 << new_base)) { inst.error = _("invalid register list"); @@ -7506,10 +7561,10 @@ vfp_sp_reg_list (char ** str, enum vfp_sp_reg_pos pos) (*str)++; if ((high_range - = arm_reg_parse (str, all_reg_maps[REG_TYPE_SN].htab)) + = arm_reg_parse (str, all_reg_maps[regtype].htab)) == FAIL) { - inst.error = _(all_reg_maps[REG_TYPE_SN].expected); + inst.error = _(all_reg_maps[regtype].expected); return FAIL; } @@ -7534,37 +7589,33 @@ vfp_sp_reg_list (char ** str, enum vfp_sp_reg_pos pos) } while (skip_past_comma (str) != FAIL); - if (**str != '}') - { - inst.error = _("invalid register list"); - return FAIL; - } - (*str)++; - range = count; - /* Sanity check -- should have raised a parse error above. */ - if (count == 0 || count > 32) + if (count == 0 || count > max_regs) abort (); + *pbase = base_reg; + /* Final test -- the registers must be consecutive. */ - while (count--) + mask >>= base_reg; + for (i = 0; i < count; i++) { - if ((mask & (1 << base_reg++)) == 0) + if ((mask & (1u << i)) == 0) { inst.error = _("non-contiguous register range"); return FAIL; } } - inst.instruction = tempinst | base_bits; - return range; + return count; } static void do_vfp_reg2_from_sp2 (char * str) { + int reg; + skip_whitespace (str); if (reg_required_here (&str, 12) == FAIL @@ -7578,11 +7629,12 @@ do_vfp_reg2_from_sp2 (char * str) } /* We require exactly two consecutive SP registers. */ - if (vfp_sp_reg_list (&str, VFP_REG_Sm) != 2) + if (vfp_parse_reg_list (&str, ®, 0) != 2) { if (! inst.error) inst.error = _("only two consecutive VFP SP registers allowed here"); } + vfp_sp_encode_reg (reg, VFP_REG_Sm); end_of_line (str); } @@ -7609,14 +7661,17 @@ do_vfp_sp_from_reg (char * str) static void do_vfp_sp2_from_reg2 (char * str) { + int reg; + skip_whitespace (str); /* We require exactly two consecutive SP registers. */ - if (vfp_sp_reg_list (&str, VFP_REG_Sm) != 2) + if (vfp_parse_reg_list (&str, ®, 0) != 2) { if (! inst.error) inst.error = _("only two consecutive VFP SP registers allowed here"); } + vfp_sp_encode_reg (reg, VFP_REG_Sm); if (skip_past_comma (&str) == FAIL || reg_required_here (&str, 12) == FAIL @@ -7851,122 +7906,12 @@ do_vfp_dp_ldst (char * str) end_of_line (str); } -static long -vfp_dp_reg_list (char ** str) -{ - long range = 0; - int base_reg = 0; - int new_base; - int count = 0; - long tempinst; - unsigned long mask = 0; - int warned = 0; - - if (**str != '{') - return FAIL; - - (*str)++; - skip_whitespace (*str); - - tempinst = inst.instruction; - - do - { - inst.instruction = 0; - - if ((new_base = vfp_dp_reg_required_here (str, VFP_REG_Dd)) == FAIL) - return FAIL; - - if (count == 0 || base_reg > new_base) - { - base_reg = new_base; - range = inst.instruction; - } - - if (mask & (1 << new_base)) - { - inst.error = _("invalid register list"); - return FAIL; - } - - if ((mask >> new_base) != 0 && ! warned) - { - as_tsktsk (_("register list not in ascending order")); - warned = 1; - } - - mask |= 1 << new_base; - count++; - - skip_whitespace (*str); - - if (**str == '-') /* We have the start of a range expression */ - { - int high_range; - - (*str)++; - - if ((high_range - = arm_reg_parse (str, all_reg_maps[REG_TYPE_DN].htab)) - == FAIL) - { - inst.error = _(all_reg_maps[REG_TYPE_DN].expected); - return FAIL; - } - - if (high_range <= new_base) - { - inst.error = _("register range not in ascending order"); - return FAIL; - } - - for (new_base++; new_base <= high_range; new_base++) - { - if (mask & (1 << new_base)) - { - inst.error = _("invalid register list"); - return FAIL; - } - - mask |= 1 << new_base; - count++; - } - } - } - while (skip_past_comma (str) != FAIL); - - if (**str != '}') - { - inst.error = _("invalid register list"); - return FAIL; - } - - (*str)++; - - range |= 2 * count; - - /* Sanity check -- should have raised a parse error above. */ - if (count == 0 || count > 16) - abort (); - - /* Final test -- the registers must be consecutive. */ - while (count--) - { - if ((mask & (1 << base_reg++)) == 0) - { - inst.error = _("non-contiguous register range"); - return FAIL; - } - } - - inst.instruction = tempinst; - return range; -} static void vfp_sp_ldstm (char * str, enum vfp_ldstm_type ldstm_type) { - long range; + int count; + int reg; skip_whitespace (str); @@ -7987,21 +7932,23 @@ vfp_sp_ldstm (char * str, enum vfp_ldstm_type ldstm_type) } if (skip_past_comma (&str) == FAIL - || (range = vfp_sp_reg_list (&str, VFP_REG_Sd)) == FAIL) + || (count = vfp_parse_reg_list (&str, ®, 0)) == FAIL) { if (!inst.error) inst.error = BAD_ARGS; return; } + vfp_sp_encode_reg (reg, VFP_REG_Sd); - inst.instruction |= range; + inst.instruction |= count; end_of_line (str); } static void vfp_dp_ldstm (char * str, enum vfp_ldstm_type ldstm_type) { - long range; + int count; + int reg; skip_whitespace (str); @@ -8022,17 +7969,18 @@ vfp_dp_ldstm (char * str, enum vfp_ldstm_type ldstm_type) } if (skip_past_comma (&str) == FAIL - || (range = vfp_dp_reg_list (&str)) == FAIL) + || (count = vfp_parse_reg_list (&str, ®, 1)) == FAIL) { if (!inst.error) inst.error = BAD_ARGS; return; } + count <<= 1; if (ldstm_type == VFP_LDSTMIAX || ldstm_type == VFP_LDSTMDBX) - range += 1; + count += 1; - inst.instruction |= range; + inst.instruction |= (reg << 12) | count; end_of_line (str); } @@ -10071,7 +10019,7 @@ static const struct asm_opcode insns[] = { "wfe", 0xe320f002, 3, ARM_EXT_V6K, do_empty}, { "wfi", 0xe320f003, 3, ARM_EXT_V6K, do_empty}, { "yield", 0xe320f001, 5, ARM_EXT_V6K, do_empty}, - + /* ARM V6Z. */ { "smi", 0xe1600070, 3, ARM_EXT_V6Z, do_smi}, @@ -13692,6 +13640,1128 @@ s_arm_rel31 (int ignored ATTRIBUTE_UNUSED) demand_empty_rest_of_line (); } + +/* Code to deal with unwinding tables. */ + +static void add_unwind_adjustsp (offsetT); + +/* Switch to section NAME and create section if necessary. It's + rather ugly that we have to manipulate input_line_pointer but I + don't see any other way to accomplish the same thing without + changing obj-elf.c (which may be the Right Thing, in the end). + Copied from tc-ia64.c. */ + +static void +set_section (char *name) +{ + char *saved_input_line_pointer; + + saved_input_line_pointer = input_line_pointer; + input_line_pointer = name; + obj_elf_section (0); + input_line_pointer = saved_input_line_pointer; +} + +/* Cenerate and deferred unwind frame offset. */ + +static void +flush_pending_unwind (void) +{ + offsetT offset; + + offset = unwind.pending_offset; + unwind.pending_offset = 0; + if (offset != 0) + add_unwind_adjustsp (offset); +} + +/* Add an opcode to this list for this function. Two-byte opcodes should + be passed as op[0] << 8 | op[1]. The list of opcodes is built in reverse + order. */ + +static void +add_unwind_opcode (valueT op, int length) +{ + /* Add any deferred stack adjustment. */ + if (unwind.pending_offset) + flush_pending_unwind (); + + unwind.sp_restored = 0; + + if (unwind.opcode_count + length > unwind.opcode_alloc) + { + unwind.opcode_alloc += ARM_OPCODE_CHUNK_SIZE; + if (unwind.opcodes) + unwind.opcodes = xrealloc (unwind.opcodes, + unwind.opcode_alloc); + else + unwind.opcodes = xmalloc (unwind.opcode_alloc); + } + while (length > 0) + { + length--; + unwind.opcodes[unwind.opcode_count] = op & 0xff; + op >>= 8; + unwind.opcode_count++; + } +} + +/* Add unwind opcodes to adjust the stack pointer. */ + +static void +add_unwind_adjustsp (offsetT offset) +{ + valueT op; + + if (offset > 0x200) + { + /* We need at most 5 bytes to hold a 32-bit value in a uleb128. */ + char bytes[5]; + int n; + valueT o; + + /* Long form: 0xb2, uleb128. */ + /* This might not fit in a word so add the individual bytes, + remembering the list is built in reverse order. */ + o = (valueT) ((offset - 0x204) >> 2); + if (o == 0) + add_unwind_opcode (0, 1); + + /* Calculate the uleb128 encoding of the offset. */ + n = 0; + while (o) + { + bytes[n] = o & 0x7f; + o >>= 7; + if (o) + bytes[n] |= 0x80; + n++; + } + /* Add the insn. */ + for (; n; n--) + add_unwind_opcode (bytes[n - 1], 1); + add_unwind_opcode (0xb2, 1); + } + else if (offset > 0x100) + { + /* Two short opcodes. */ + add_unwind_opcode (0x3f, 1); + op = (offset - 0x104) >> 2; + add_unwind_opcode (op, 1); + } + else if (offset > 0) + { + /* Short opcode. */ + op = (offset - 4) >> 2; + add_unwind_opcode (op, 1); + } + else if (offset < 0) + { + offset = -offset; + while (offset > 0x100) + { + add_unwind_opcode (0x7f, 1); + offset -= 0x100; + } + op = ((offset - 4) >> 2) | 0x40; + add_unwind_opcode (op, 1); + } +} + +/* Finish the list of unwind opcodes for this function. */ +static void +finish_unwind_opcodes (void) +{ + valueT op; + + if (unwind.fp_used) + { + /* Adjust sp as neccessary. */ + unwind.pending_offset += unwind.fp_offset - unwind.frame_size; + flush_pending_unwind (); + + /* After restoring sp from the frame pointer. */ + op = 0x90 | unwind.fp_reg; + add_unwind_opcode (op, 1); + } + else + flush_pending_unwind (); +} + + +/* Start an exception table entry. If idx is nonzero this is an index table + entry. */ + +static void +start_unwind_section (const segT text_seg, int idx) +{ + const char * text_name; + const char * prefix; + const char * prefix_once; + size_t prefix_len; + size_t text_len; + char * sec_name; + size_t sec_name_len; + + if (idx) + { + prefix = ELF_STRING_ARM_unwind; + prefix_once = ELF_STRING_ARM_unwind_once; + } + else + { + prefix = ELF_STRING_ARM_unwind_info; + prefix_once = ELF_STRING_ARM_unwind_info_once; + } + + text_name = segment_name (text_seg); + if (streq (text_name, ".text")) + text_name = ""; + + if (strncmp (text_name, ".gnu.linkonce.t.", + strlen (".gnu.linkonce.t.")) == 0) + { + prefix = prefix_once; + text_name += strlen (".gnu.linkonce.t."); + } + + prefix_len = strlen (prefix); + text_len = strlen (text_name); + sec_name_len = prefix_len + text_len; + sec_name = alloca (sec_name_len + 1); + memcpy (sec_name, prefix, prefix_len); + memcpy (sec_name + prefix_len, text_name, text_len); + sec_name[prefix_len + text_len] = '\0'; + + /* Handle COMDAT group. */ + if (prefix != prefix_once && (text_seg->flags & SEC_LINK_ONCE) != 0) + { + char *section; + size_t len, group_name_len; + const char *group_name = elf_group_name (text_seg); + + if (group_name == NULL) + { + as_bad ("Group section `%s' has no group signature", + segment_name (text_seg)); + ignore_rest_of_line (); + return; + } + /* We have to construct a fake section directive. */ + group_name_len = strlen (group_name); + if (idx) + prefix_len = 13; + else + prefix_len = 16; + + len = (sec_name_len + + prefix_len /* ,"aG",%sectiontype, */ + + group_name_len /* ,group_name */ + + 7); /* ,comdat */ + + section = alloca (len + 1); + memcpy (section, sec_name, sec_name_len); + if (idx) + memcpy (section + sec_name_len, ",\"aG\",%exidx,", 13); + else + memcpy (section + sec_name_len, ",\"aG\",%progbits,", 16); + memcpy (section + sec_name_len + prefix_len, group_name, group_name_len); + memcpy (section + len - 7, ",comdat", 7); + section [len] = '\0'; + set_section (section); + } + else + { + set_section (sec_name); + bfd_set_section_flags (stdoutput, now_seg, + SEC_LOAD | SEC_ALLOC | SEC_READONLY); + } + + /* Set the setion link for index tables. */ + if (idx) + elf_linked_to_section (now_seg) = text_seg; +} + + +/* Start an unwind table entry. HAVE_DATA is nonzero if we have additional + personality routine data. Returns zero, or the index table value for + and inline entry. */ + +static valueT +create_unwind_entry (int have_data) +{ + int size; + addressT where; + unsigned char *ptr; + /* The current word of data. */ + valueT data; + /* The number of bytes left in this word. */ + int n; + + finish_unwind_opcodes (); + + /* Remember the current text section. */ + unwind.saved_seg = now_seg; + unwind.saved_subseg = now_subseg; + + start_unwind_section (now_seg, 0); + + if (unwind.personality_routine == NULL) + { + if (unwind.personality_index == -2) + { + if (have_data) + as_bad (_("handerdata in cantunwind frame")); + return 1; /* EXIDX_CANTUNWIND. */ + } + + /* Use a default personality routine if none is specified. */ + if (unwind.personality_index == -1) + { + if (unwind.opcode_count > 3) + unwind.personality_index = 1; + else + unwind.personality_index = 0; + } + + /* Space for the personality routine entry. */ + if (unwind.personality_index == 0) + { + if (unwind.opcode_count > 3) + as_bad (_("too many unwind opcodes for personality routine 0")); + + if (!have_data) + { + /* All the data is inline in the index table. */ + data = 0x80; + n = 3; + while (unwind.opcode_count > 0) + { + unwind.opcode_count--; + data = (data << 8) | unwind.opcodes[unwind.opcode_count]; + n--; + } + + /* Pad with "finish" opcodes. */ + while (n--) + data = (data << 8) | 0xb0; + + return data; + } + size = 0; + } + else + /* We get two opcodes "free" in the first word. */ + size = unwind.opcode_count - 2; + } + else + /* An extra byte is required for the opcode count. */ + size = unwind.opcode_count + 1; + + size = (size + 3) >> 2; + if (size > 0xff) + as_bad (_("too many unwind opcodes")); + + frag_align (2, 0, 0); + record_alignment (now_seg, 2); + unwind.table_entry = expr_build_dot (); + + /* Allocate the table entry. */ + ptr = frag_more ((size << 2) + 4); + where = frag_now_fix () - ((size << 2) + 4); + + switch (unwind.personality_index) + { + case -1: + /* ??? Should this be a PLT generating relocation? */ + /* Custom personality routine. */ + fix_new (frag_now, where, 4, unwind.personality_routine, 0, 1, + BFD_RELOC_ARM_PREL31); + where += 4; + ptr += 4; + + /* Set the first byte to the number of additional words. */ + data = size - 1; + n = 3; + break; + + /* ABI defined personality routines. */ + /* TODO: Emit R_ARM_NONE to the personality routine. */ + case 0: + /* Three opcodes bytes are packed into the first word. */ + data = 0x80; + n = 3; + break; + + case 1: + case 2: + /* The size and first two opcode bytes go in the first word. */ + data = ((0x80 + unwind.personality_index) << 8) | size; + n = 2; + break; + + default: + /* Should never happen. */ + abort (); + } + + /* Pack the opcodes into words (MSB first), reversing the list at the same + time. */ + while (unwind.opcode_count > 0) + { + if (n == 0) + { + md_number_to_chars (ptr, data, 4); + ptr += 4; + n = 4; + data = 0; + } + unwind.opcode_count--; + n--; + data = (data << 8) | unwind.opcodes[unwind.opcode_count]; + } + + /* Finish off the last word. */ + if (n < 4) + { + /* Pad with "finish" opcodes. */ + while (n--) + data = (data << 8) | 0xb0; + + md_number_to_chars (ptr, data, 4); + } + + if (!have_data) + { + /* Add an empty descriptor if there is no user-specified data. */ + ptr = frag_more (4); + md_number_to_chars (ptr, 0, 4); + } + + return 0; +} + + +/* Parse an unwind_fnstart directive. Simply records the current location. */ + +static void +s_arm_unwind_fnstart (int ignored ATTRIBUTE_UNUSED) +{ + demand_empty_rest_of_line (); + /* Mark the start of the function. */ + unwind.proc_start = expr_build_dot (); + + /* Reset the rest of the unwind info. */ + unwind.opcode_count = 0; + unwind.table_entry = NULL; + unwind.personality_routine = NULL; + unwind.personality_index = -1; + unwind.frame_size = 0; + unwind.fp_offset = 0; + unwind.fp_reg = 13; + unwind.fp_used = 0; + unwind.sp_restored = 0; +} + + +/* Parse a handlerdata directive. Creates the exception handling table entry + for the function. */ + +static void +s_arm_unwind_handlerdata (int ignored ATTRIBUTE_UNUSED) +{ + demand_empty_rest_of_line (); + if (unwind.table_entry) + as_bad (_("dupicate .handlerdata directive")); + + create_unwind_entry (1); +} + +/* Parse an unwind_fnend directive. Generates the index table entry. */ + +static void +s_arm_unwind_fnend (int ignored ATTRIBUTE_UNUSED) +{ + long where; + unsigned char *ptr; + valueT val; + + demand_empty_rest_of_line (); + + /* Add eh table entry. */ + if (unwind.table_entry == NULL) + val = create_unwind_entry (0); + else + val = 0; + + /* Add index table entry. This is two words. */ + start_unwind_section (unwind.saved_seg, 1); + frag_align (2, 0, 0); + record_alignment (now_seg, 2); + + ptr = frag_more (8); + where = frag_now_fix () - 8; + + /* Self relative offset of the function start. */ + fix_new (frag_now, where, 4, unwind.proc_start, 0, 1, + BFD_RELOC_32); + + if (val) + /* Inline exception table entry. */ + md_number_to_chars (ptr + 4, val, 4); + else + /* Self relative offset of the table entry. */ + fix_new (frag_now, where + 4, 4, unwind.table_entry, 0, 1, + BFD_RELOC_ARM_PREL31); + + /* Restore the original section. */ + subseg_set (unwind.saved_seg, unwind.saved_subseg); +} + + +/* Parse an unwind_cantunwind directive. */ + +static void +s_arm_unwind_cantunwind (int ignored ATTRIBUTE_UNUSED) +{ + demand_empty_rest_of_line (); + if (unwind.personality_routine || unwind.personality_index != -1) + as_bad (_("personality routine specified for cantunwind frame")); + + unwind.personality_index = -2; +} + + +/* Parse a personalityindex directive. */ + +static void +s_arm_unwind_personalityindex (int ignored ATTRIBUTE_UNUSED) +{ + expressionS exp; + + if (unwind.personality_routine || unwind.personality_index != -1) + as_bad (_("duplicate .personalityindex directive")); + + SKIP_WHITESPACE (); + + expression (&exp); + + if (exp.X_op != O_constant + || exp.X_add_number < 0 || exp.X_add_number > 15) + { + as_bad (_("bad personality routine number")); + ignore_rest_of_line (); + return; + } + + unwind.personality_index = exp.X_add_number; + + demand_empty_rest_of_line (); +} + + +/* Parse a personality directive. */ + +static void +s_arm_unwind_personality (int ignored ATTRIBUTE_UNUSED) +{ + char *name, *p, c; + + if (unwind.personality_routine || unwind.personality_index != -1) + as_bad (_("duplicate .personality directive")); + + SKIP_WHITESPACE (); + name = input_line_pointer; + c = get_symbol_end (); + p = input_line_pointer; + unwind.personality_routine = symbol_find_or_make (name); + *p = c; + SKIP_WHITESPACE (); + demand_empty_rest_of_line (); +} + + +/* Parse a directive saving core registers. */ + +static void +s_arm_unwind_save_core (void) +{ + valueT op; + long range; + int n; + + SKIP_WHITESPACE (); + range = reg_list (&input_line_pointer); + if (range == FAIL) + { + as_bad (_("expected register list")); + ignore_rest_of_line (); + return; + } + + demand_empty_rest_of_line (); + + /* Turn .unwind_movsp ip followed by .unwind_save {..., ip, ...} + into .unwind_save {..., sp...}. We aren't bothered about the value of + ip because it is clobbered by calls. */ + if (unwind.sp_restored && unwind.fp_reg == 12 + && (range & 0x3000) == 0x1000) + { + unwind.opcode_count--; + unwind.sp_restored = 0; + range = (range | 0x2000) & ~0x1000; + unwind.pending_offset = 0; + } + + /* See if we can use the short opcodes. These pop a block of upto 8 + registers starting with r4, plus maybe r14. */ + for (n = 0; n < 8; n++) + { + /* Break at the first non-saved register. */ + if ((range & (1 << (n + 4))) == 0) + break; + } + /* See if there are any other bits set. */ + if (n == 0 || (range & (0xfff0 << n) & 0xbff0) != 0) + { + /* Use the long form. */ + op = 0x8000 | ((range >> 4) & 0xfff); + add_unwind_opcode (op, 2); + } + else + { + /* Use the short form. */ + if (range & 0x4000) + op = 0xa8; /* Pop r14. */ + else + op = 0xa0; /* Do not pop r14. */ + op |= (n - 1); + add_unwind_opcode (op, 1); + } + + /* Pop r0-r3. */ + if (range & 0xf) + { + op = 0xb100 | (range & 0xf); + add_unwind_opcode (op, 2); + } + + /* Record the number of bytes pushed. */ + for (n = 0; n < 16; n++) + { + if (range & (1 << n)) + unwind.frame_size += 4; + } +} + + +/* Parse a directive saving FPA registers. */ + +static void +s_arm_unwind_save_fpa (int reg) +{ + expressionS exp; + int num_regs; + valueT op; + + /* Get Number of registers to transfer. */ + if (skip_past_comma (&input_line_pointer) != FAIL) + expression (&exp); + else + exp.X_op = O_illegal; + + if (exp.X_op != O_constant) + { + as_bad (_("expected , ")); + ignore_rest_of_line (); + return; + } + + num_regs = exp.X_add_number; + + if (num_regs < 1 || num_regs > 4) + { + as_bad (_("number of registers must be in the range [1:4]")); + ignore_rest_of_line (); + return; + } + + demand_empty_rest_of_line (); + + if (reg == 4) + { + /* Short form. */ + op = 0xb4 | (num_regs - 1); + add_unwind_opcode (op, 1); + } + else + { + /* Long form. */ + op = 0xc800 | (reg << 4) | (num_regs - 1); + add_unwind_opcode (op, 2); + } + unwind.frame_size += num_regs * 12; +} + + +/* Parse a directive saving VFP registers. */ + +static void +s_arm_unwind_save_vfp (void) +{ + int count; + int reg; + valueT op; + + count = vfp_parse_reg_list (&input_line_pointer, ®, 1); + if (count == FAIL) + { + as_bad (_("expected register list")); + ignore_rest_of_line (); + return; + } + + demand_empty_rest_of_line (); + + if (reg == 8) + { + /* Short form. */ + op = 0xb8 | (count - 1); + add_unwind_opcode (op, 1); + } + else + { + /* Long form. */ + op = 0xb300 | (reg << 4) | (count - 1); + add_unwind_opcode (op, 2); + } + unwind.frame_size += count * 8 + 4; +} + + +/* Parse a directive saving iWMMXt registers. */ + +static void +s_arm_unwind_save_wmmx (void) +{ + int reg; + int hi_reg; + int i; + unsigned wcg_mask; + unsigned wr_mask; + valueT op; + + if (*input_line_pointer == '{') + input_line_pointer++; + + wcg_mask = 0; + wr_mask = 0; + do + { + reg = arm_reg_parse (&input_line_pointer, + all_reg_maps[REG_TYPE_IWMMXT].htab); + + if (wr_register (reg)) + { + i = reg & ~WR_PREFIX; + if (wr_mask >> i) + as_tsktsk (_("register list not in ascending order")); + wr_mask |= 1 << i; + } + else if (wcg_register (reg)) + { + i = (reg & ~WC_PREFIX) - 8; + if (wcg_mask >> i) + as_tsktsk (_("register list not in ascending order")); + wcg_mask |= 1 << i; + } + else + { + as_bad (_("expected wr or wcgr")); + goto error; + } + + SKIP_WHITESPACE (); + if (*input_line_pointer == '-') + { + hi_reg = arm_reg_parse (&input_line_pointer, + all_reg_maps[REG_TYPE_IWMMXT].htab); + if (wr_register (reg) && wr_register (hi_reg)) + { + for (; reg < hi_reg; reg++) + wr_mask |= 1 << (reg & ~WR_PREFIX); + } + else if (wcg_register (reg) && wcg_register (hi_reg)) + { + for (; reg < hi_reg; reg++) + wcg_mask |= 1 << ((reg & ~WC_PREFIX) - 8); + } + else + { + as_bad (_("bad register range")); + goto error; + } + } + } + while (skip_past_comma (&input_line_pointer) != FAIL); + + SKIP_WHITESPACE (); + if (*input_line_pointer == '}') + input_line_pointer++; + + demand_empty_rest_of_line (); + + if (wr_mask && wcg_mask) + { + as_bad (_("inconsistent register types")); + goto error; + } + + /* Generate any deferred opcodes becuuse we're going to be looking at + the list. */ + flush_pending_unwind (); + + if (wcg_mask) + { + for (i = 0; i < 16; i++) + { + if (wcg_mask & (1 << i)) + unwind.frame_size += 4; + } + op = 0xc700 | wcg_mask; + add_unwind_opcode (op, 2); + } + else + { + for (i = 0; i < 16; i++) + { + if (wr_mask & (1 << i)) + unwind.frame_size += 8; + } + /* Attempt to combine with a previous opcode. We do this because gcc + likes to output separate unwind directives for a single block of + registers. */ + if (unwind.opcode_count > 0) + { + i = unwind.opcodes[unwind.opcode_count - 1]; + if ((i & 0xf8) == 0xc0) + { + i &= 7; + /* Only merge if the blocks are contiguous. */ + if (i < 6) + { + if ((wr_mask & 0xfe00) == (1 << 9)) + { + wr_mask |= ((1 << (i + 11)) - 1) & 0xfc00; + unwind.opcode_count--; + } + } + else if (i == 6 && unwind.opcode_count >= 2) + { + i = unwind.opcodes[unwind.opcode_count - 2]; + reg = i >> 4; + i &= 0xf; + + op = 0xffff << (reg - 1); + if (reg > 0 + || ((wr_mask & op) == (1u << (reg - 1)))) + { + op = (1 << (reg + i + 1)) - 1; + op &= ~((1 << reg) - 1); + wr_mask |= op; + unwind.opcode_count -= 2; + } + } + } + } + + hi_reg = 15; + /* We want to generate opcodes in the order the registers have been + saved, ie. descending order. */ + for (reg = 15; reg >= -1; reg--) + { + /* Save registers in blocks. */ + if (reg < 0 + || !(wr_mask & (1 << reg))) + { + /* We found an unsaved reg. Generate opcodes to save the + preceeding block. */ + if (reg != hi_reg) + { + if (reg == 9) + { + /* Short form. */ + op = 0xc0 | (hi_reg - 10); + add_unwind_opcode (op, 1); + } + else + { + /* Long form. */ + op = 0xc600 | ((reg + 1) << 4) | ((hi_reg - reg) - 1); + add_unwind_opcode (op, 2); + } + } + hi_reg = reg - 1; + } + } + } + return; +error: + ignore_rest_of_line (); +} + + +/* Parse an unwind_save directive. */ + +static void +s_arm_unwind_save (int ignored ATTRIBUTE_UNUSED) +{ + char *saved_ptr; + int reg; + + /* Figure out what sort of save we have. */ + SKIP_WHITESPACE (); + saved_ptr = input_line_pointer; + + reg = arm_reg_parse (&input_line_pointer, all_reg_maps[REG_TYPE_FN].htab); + if (reg != FAIL) + { + s_arm_unwind_save_fpa (reg); + return; + } + + if (*input_line_pointer == '{') + input_line_pointer++; + + SKIP_WHITESPACE (); + + reg = arm_reg_parse (&input_line_pointer, all_reg_maps[REG_TYPE_RN].htab); + if (reg != FAIL) + { + input_line_pointer = saved_ptr; + s_arm_unwind_save_core (); + return; + } + + reg = arm_reg_parse (&input_line_pointer, all_reg_maps[REG_TYPE_DN].htab); + if (reg != FAIL) + { + input_line_pointer = saved_ptr; + s_arm_unwind_save_vfp (); + return; + } + + reg = arm_reg_parse (&input_line_pointer, + all_reg_maps[REG_TYPE_IWMMXT].htab); + if (reg != FAIL) + { + input_line_pointer = saved_ptr; + s_arm_unwind_save_wmmx (); + return; + } + + /* TODO: Maverick registers. */ + as_bad (_("unrecognised register")); +} + + +/* Parse an unwind_movsp directive. */ + +static void +s_arm_unwind_movsp (int ignored ATTRIBUTE_UNUSED) +{ + int reg; + valueT op; + + SKIP_WHITESPACE (); + reg = reg_required_here (&input_line_pointer, -1); + if (reg == FAIL) + { + as_bad (_("ARM register expected")); + ignore_rest_of_line (); + return; + } + + if (reg == 13 || reg == 15) + { + as_bad (_("r%d not permitted in .unwind_movsp directive"), reg); + ignore_rest_of_line (); + return; + } + + if (unwind.fp_reg != 13) + as_bad (_("unexpected .unwind_movsp directive")); + + /* Generate opcode to restore the value. */ + op = 0x90 | reg; + add_unwind_opcode (op, 1); + + /* Record the information for later. */ + unwind.fp_reg = reg; + unwind.fp_offset = unwind.frame_size; + unwind.sp_restored = 1; + demand_empty_rest_of_line (); +} + + +/* Parse #. */ + +static int +require_hashconst (int * val) +{ + expressionS exp; + + SKIP_WHITESPACE (); + if (*input_line_pointer == '#') + { + input_line_pointer++; + expression (&exp); + } + else + exp.X_op = O_illegal; + + if (exp.X_op != O_constant) + { + as_bad (_("expected #constant")); + ignore_rest_of_line (); + return FAIL; + } + *val = exp.X_add_number; + return SUCCESS; +} + +/* Parse an unwind_pad directive. */ + +static void +s_arm_unwind_pad (int ignored ATTRIBUTE_UNUSED) +{ + int offset; + + if (require_hashconst (&offset) == FAIL) + return; + + if (offset & 3) + { + as_bad (_("stack increment must be multiple of 4")); + ignore_rest_of_line (); + return; + } + + /* Don't generate any opcodes, just record the details for later. */ + unwind.frame_size += offset; + unwind.pending_offset += offset; + + demand_empty_rest_of_line (); +} + +/* Parse an unwind_setfp directive. */ + +static void +s_arm_unwind_setfp (int ignored ATTRIBUTE_UNUSED) +{ + int sp_reg; + int fp_reg; + int offset; + + fp_reg = reg_required_here (&input_line_pointer, -1); + if (skip_past_comma (&input_line_pointer) == FAIL) + sp_reg = FAIL; + else + sp_reg = reg_required_here (&input_line_pointer, -1); + + if (fp_reg == FAIL || sp_reg == FAIL) + { + as_bad (_("expected , ")); + ignore_rest_of_line (); + return; + } + + /* Optonal constant. */ + if (skip_past_comma (&input_line_pointer) != FAIL) + { + if (require_hashconst (&offset) == FAIL) + return; + } + else + offset = 0; + + demand_empty_rest_of_line (); + + if (sp_reg != 13 && sp_reg != unwind.fp_reg) + { + as_bad (_("register must be either sp or set by a previous" + "unwind_movsp directive")); + return; + } + + /* Don't generate any opcodes, just record the information for later. */ + unwind.fp_reg = fp_reg; + unwind.fp_used = 1; + if (sp_reg == 13) + unwind.fp_offset = unwind.frame_size - offset; + else + unwind.fp_offset -= offset; +} + +/* Parse an unwind_raw directive. */ + +static void +s_arm_unwind_raw (int ignored ATTRIBUTE_UNUSED) +{ + expressionS exp; + /* This is an arbitary limit. */ + unsigned char op[16]; + int count; + + SKIP_WHITESPACE (); + expression (&exp); + if (exp.X_op == O_constant + && skip_past_comma (&input_line_pointer) != FAIL) + { + unwind.frame_size += exp.X_add_number; + expression (&exp); + } + else + exp.X_op = O_illegal; + + if (exp.X_op != O_constant) + { + as_bad (_("expected , ")); + ignore_rest_of_line (); + return; + } + + count = 0; + + /* Parse the opcode. */ + for (;;) + { + if (count >= 16) + { + as_bad (_("unwind opcode too long")); + ignore_rest_of_line (); + } + if (exp.X_op != O_constant || exp.X_add_number & ~0xff) + { + as_bad (_("invalid unwind opcode")); + ignore_rest_of_line (); + return; + } + op[count++] = exp.X_add_number; + + /* Parse the next byte. */ + if (skip_past_comma (&input_line_pointer) == FAIL) + break; + + expression (&exp); + } + + /* Add the opcode bytes in reverse order. */ + while (count--) + add_unwind_opcode (op[count], 1); + + demand_empty_rest_of_line (); +} #endif /* OBJ_ELF */ @@ -13815,6 +14885,17 @@ const pseudo_typeS md_pseudo_table[] = { "word", s_arm_elf_cons, 4 }, { "long", s_arm_elf_cons, 4 }, { "rel31", s_arm_rel31, 0 }, + { "fnstart", s_arm_unwind_fnstart, 0 }, + { "fnend", s_arm_unwind_fnend, 0 }, + { "cantunwind", s_arm_unwind_cantunwind, 0 }, + { "personality", s_arm_unwind_personality, 0 }, + { "personalityindex", s_arm_unwind_personalityindex, 0 }, + { "handlerdata", s_arm_unwind_handlerdata, 0 }, + { "save", s_arm_unwind_save, 0 }, + { "movsp", s_arm_unwind_movsp, 0 }, + { "pad", s_arm_unwind_pad, 0 }, + { "setfp", s_arm_unwind_setfp, 0 }, + { "unwind_raw", s_arm_unwind_raw, 0 }, #else { "word", cons, 4}, #endif diff --git a/gas/doc/c-arm.texi b/gas/doc/c-arm.texi index cb4569b100..edd233b854 100644 --- a/gas/doc/c-arm.texi +++ b/gas/doc/c-arm.texi @@ -407,6 +407,104 @@ it prevents accurate control of the placement of literal pools. @item .pool This is a synonym for .ltorg. +@cindex @code{.fnstart} directive, ARM +@item .unwind_fnstart +Marks the start of a function with an unwind table entry. + +@cindex @code{.fnend} directive, ARM +@item .unwind_fnend +Marks the end of a function with an unwind table entry. The unwind index +table entry is created when this directive is processed. + +If no personality routine has been specified then standard personality +routine 0 or 1 will be used, depending on the number of unwind opcodes +required. + +@cindex @code{.cantunwind} directive, ARM +@item .cantunwind +Prevents unwinding through the current function. No personality routine +or exception table data is required or permitted. + +@cindex @code{.personality} directive, ARM +@item .personality @var{name} +Sets the personality routine for the current function to @var{name}. + +@cindex @code{.personalityindex} directive, ARM +@item .personalityindex @var{index} +Sets the personality routine for the current function to the EABI standard +routine number @var{index} + +@cindex @code{.handlerdata} directive, ARM +@item .handlerdata +Marks the end of the current function, and the start of the exception table +entry for that function. Anything between this directive and the +@code{.fnend} directive will be added to the exception table entry. + +Must be preceded by a @code{.personality} or @code{.personalityindex} +directive. + +@cindex @code{.save} directive, ARM +@item .save @var{reglist} +Generate unwinder annotations to restore the registers in @var{reglist}. +The format of @var{reglist} is the same as the corresponding store-multiple +instruction. + +@smallexample +@exdent @emph{core registers} + .save @{r4, r5, r6, lr@} + stmfd sp!, @{r4, r5, r6, lr@} +@exdent @emph{FPA registers} + .save f4, 2 + sfmfd f4, 2, [sp]! +@exdent @emph{VFP registers} + .save @{d8, d9, d10@} + fstmdf sp!, @{d8, d9, d10@} +@exdent @emph{iWMMXt registers} + .save @{wr10, wr11@} + wstrd wr11, [sp, #-8]! + wstrd wr10, [sp, #-8]! +or + .save wr11 + wstrd wr11, [sp, #-8]! + .save wr10 + wstrd wr10, [sp, #-8]! +@end smallexample + +@cindex @code{.pad} directive, ARM +@item .pad #@var{count} +Generate unwinder annotations for a stack adjustment of @var{count} bytes. +A positive value indicates the function prologue allocated stack space by +decrementing the stack pointer. + +@cindex @code{.movsp} directive, ARM +@item .movsp @var{reg} +Tell the unwinder that @var{reg} contains the current stack pointer. + +@cindex @code{.setfp} directive, ARM +@item .setfp @var{fpreg}, @var{spreg} [, #@var{offset}] +Make all unwinder annotations relaive to a frame pointer. Without this +the unwinder will use offsets from the stack pointer. + +The syntax of this directive is the same as the @code{sub} or @code{mov} +instruction used to set the frame pointer. @var{spreg} must be either +@code{sp} or mentioned in a previous @code{.movsp} directive. + +@smallexample +.movsp ip +mov ip, sp +@dots{} +.setfp fp, ip, #4 +sub fp, ip, #4 +@end smallexample + +@cindex @code{.unwind_raw} directive, ARM +@item .raw @var{offset}, @var{byte1}, @dots{} +Insert one of more arbitary unwind opcode bytes, which are known to adjust +the stack pointer by @var{offset} bytes. + +For example @code{.unwind_raw 4, 0xb1, 0x01} is equivalent to +@code{.save @{r0@}} + @end table @node ARM Opcodes diff --git a/gas/testsuite/gas/arm/arm.exp b/gas/testsuite/gas/arm/arm.exp index 732468a0a4..d1578eccb6 100644 --- a/gas/testsuite/gas/arm/arm.exp +++ b/gas/testsuite/gas/arm/arm.exp @@ -58,10 +58,11 @@ if {[istarget *arm*-*-*] || [istarget "xscale-*-*"]} then { run_errors_test "r15-bad" "" "Invalid use of r15 errors" run_errors_test "undefined" "" "Undefined local label error" - if {[istarget *-*-elf*] || [istarget *-*-linux*]} then { + if {[istarget *-*-*elf*] || [istarget *-*-linux*] || [istarget *-*-*eabi]} then { run_dump_test "pic" run_dump_test "mapping" gas_test "bignum1.s" "" $stdoptlist "bignums" + run_dump_test "unwind" } if {! [istarget arm*-*-aout] && ![istarget arm-*-pe]} then { diff --git a/gas/testsuite/gas/arm/unwind.d b/gas/testsuite/gas/arm/unwind.d new file mode 100644 index 0000000000..63f9fdbff2 --- /dev/null +++ b/gas/testsuite/gas/arm/unwind.d @@ -0,0 +1,33 @@ +#objdump: -sr +#name: Unwind table generation + +.*: file format.* + +RELOCATION RECORDS FOR \[.ARM.extab\]: +OFFSET TYPE VALUE +0000000c R_ARM_PREL31 .text + + +RELOCATION RECORDS FOR \[.ARM.exidx\]: +OFFSET TYPE VALUE +00000000 R_ARM_REL32 .text +00000008 R_ARM_REL32 .text +0000000c R_ARM_PREL31 .ARM.extab +00000010 R_ARM_REL32 .text +00000014 R_ARM_PREL31 .ARM.extab +00000018 R_ARM_REL32 .text +0000001c R_ARM_PREL31 .ARM.extab +00000020 R_ARM_REL32 .text + + +Contents of section .text: + 0000 (0000a0e3 0100a0e3 0200a0e3 0300a0e3|e3a00000 a0e30001 e3a00002 e3a00003) .* + 0010 (0420|2004) .* +Contents of section .ARM.extab: + 0000 (449b0181 b0b08086|81019b44 8680b0b0) 00000000 00000000 .* + 0010 (8402b101 b0b0b005 2a000000 00c60181|01b10284 05b0b0b0 000000a2 8101c600) .* + 0020 (b0b0c1c1|c1c1b0b0) 00000000 .* +Contents of section .ARM.exidx: + 0000 00000000 (b0b0a880 04000000|80a8b0b0 00000004) 00000000 .* + 0010 (08000000 0c000000 0c000000 1c000000|00000008 0000000c 0000000c 0000001c) .* + 0020 (10000000 08849780|00000010 80978480) .* diff --git a/gas/testsuite/gas/arm/unwind.s b/gas/testsuite/gas/arm/unwind.s new file mode 100644 index 0000000000..43f01e6a0f --- /dev/null +++ b/gas/testsuite/gas/arm/unwind.s @@ -0,0 +1,46 @@ +# Test generation of unwind tables + .text +foo: @ Simple function + .fnstart + .save {r4, lr} + mov r0, #0 + .fnend +foo1: @ Typical frame pointer prologue + .fnstart + .movsp ip + @mov ip, sp + .pad #4 + .save {fp, ip, lr} + @stmfd sp!, {fp, ip, lr, pc} + .setfp fp, ip, #4 + @sub fp, ip, #4 + mov r0, #1 + .fnend +foo2: @ Custom personality routine + .fnstart + .save {r1, r4, r6, lr} + @stmfd {r1, r4, r6, lr} + mov r0, #2 + .personality foo + .handlerdata + .word 42 + .fnend +foo3: @ Saving iwmmxt registers + .fnstart + .save {wr11} + .save {wr10} + .save {wr10, wr11} + .save {wr0} + mov r0, #3 + .fnend + .code 16 +foo4: @ Thumb frame pointer + .fnstart + .save {r7, lr} + @push {r7, lr} + .setfp r7, sp + @mov r7, sp + .pad #8 + @sub sp, sp, #8 + mov r0, #4 + .fnend