alpha dwarf2 cfi support
Richard Henderson
rth@twiddle.net
Fri May 30 07:28:00 GMT 2003
I should, I suppose, eventually add the .cfi directives as well,
since they allow more freedom. However, for most purposes
re-using the ecoff directives is easier for users, and also
automatically works with lots of extant assembly files.
r~
* config/tc-alpha.c (alpha_cur_ent_sym): Remove.
(all_frame_data, plast_frame_data, cur_frame_data): New.
(s_alpha_ent): Record data for dwarf2 cfi.
(s_alpha_end, s_alpha_mask, s_alpha_frame, s_alpha_prologue): Likewise.[
(alpha_elf_md_end): Emit dwarf2 cfi for ecoff unwind directives.
* config/tc-alpha.h (md_end): New.
(DWARF2_DEFAULT_RETURN_COLUMN): New.
(DWARF2_CIE_DATA_ALIGNMENT): New.
* gas/alpha/elf-reloc-8.d: Add .eh_frame relocs.
* gas/cfi/cfi-alpha-1.d: New.
* gas/cfi/cfi-alpha-1.s: New.
* gas/cfi/cfi.exp: Run it.
Index: config/tc-alpha.c
===================================================================
RCS file: /cvs/src/src/gas/config/tc-alpha.c,v
retrieving revision 1.56
diff -c -p -d -r1.56 tc-alpha.c
*** config/tc-alpha.c 3 May 2003 16:04:11 -0000 1.56
--- config/tc-alpha.c 30 May 2003 02:55:40 -0000
***************
*** 60,65 ****
--- 60,66 ----
#ifdef OBJ_ELF
#include "elf/alpha.h"
#include "dwarf2dbg.h"
+ #include "dw2gencfi.h"
#endif
#include "safe-ctype.h"
*************** static symbolS *alpha_lit8_symbol;
*** 407,417 ****
static offsetT alpha_lit8_literal;
#endif
- #ifdef OBJ_ELF
- /* The active .ent symbol. */
- static symbolS *alpha_cur_ent_sym;
- #endif
-
/* Is the assembler not allowed to use $at? */
static int alpha_noat_on = 0;
--- 408,413 ----
*************** s_alpha_sdata (ignore)
*** 4382,4387 ****
--- 4378,4402 ----
#endif
#ifdef OBJ_ELF
+ struct alpha_elf_frame_data
+ {
+ symbolS *func_sym;
+ symbolS *func_end_sym;
+ symbolS *prologue_sym;
+ unsigned int mask;
+ unsigned int fmask;
+ int fp_regno;
+ int ra_regno;
+ offsetT frame_size;
+ offsetT mask_offset;
+ offsetT fmask_offset;
+
+ struct alpha_elf_frame_data *next;
+ };
+
+ static struct alpha_elf_frame_data *all_frame_data;
+ static struct alpha_elf_frame_data **plast_frame_data = &all_frame_data;
+ static struct alpha_elf_frame_data *cur_frame_data;
/* Handle the .section pseudo-op. This is like the usual one, but it
clears alpha_insn_label and restores auto alignment. */
*************** s_alpha_ent (dummy)
*** 4418,4429 ****
{
symbolS *sym;
! if (alpha_cur_ent_sym)
as_warn (_("nested .ent directives"));
sym = symbol_find_or_make (name);
symbol_get_bfdsym (sym)->flags |= BSF_FUNCTION;
! alpha_cur_ent_sym = sym;
/* The .ent directive is sometimes followed by a number. Not sure
what it really means, but ignore it. */
--- 4433,4453 ----
{
symbolS *sym;
! if (cur_frame_data)
as_warn (_("nested .ent directives"));
sym = symbol_find_or_make (name);
symbol_get_bfdsym (sym)->flags |= BSF_FUNCTION;
!
! cur_frame_data = calloc (1, sizeof (*cur_frame_data));
! cur_frame_data->func_sym = sym;
!
! /* Provide sensible defaults. */
! cur_frame_data->fp_regno = 30; /* sp */
! cur_frame_data->ra_regno = 26; /* ra */
!
! *plast_frame_data = cur_frame_data;
! plast_frame_data = &cur_frame_data->next;
/* The .ent directive is sometimes followed by a number. Not sure
what it really means, but ignore it. */
*************** s_alpha_end (dummy)
*** 4463,4484 ****
symbolS *sym;
sym = symbol_find (name);
! if (sym != alpha_cur_ent_sym)
as_warn (_(".end directive names different symbol than .ent"));
/* Create an expression to calculate the size of the function. */
if (sym)
{
! symbol_get_obj (sym)->size =
! (expressionS *) xmalloc (sizeof (expressionS));
! symbol_get_obj (sym)->size->X_op = O_subtract;
! symbol_get_obj (sym)->size->X_add_symbol
! = symbol_new ("L0\001", now_seg, frag_now_fix (), frag_now);
! symbol_get_obj (sym)->size->X_op_symbol = sym;
! symbol_get_obj (sym)->size->X_add_number = 0;
}
! alpha_cur_ent_sym = NULL;
*input_line_pointer = name_end;
}
--- 4487,4513 ----
symbolS *sym;
sym = symbol_find (name);
! if (!cur_frame_data)
! as_warn (_(".end directive without matching .ent"));
! else if (sym != cur_frame_data->func_sym)
as_warn (_(".end directive names different symbol than .ent"));
/* Create an expression to calculate the size of the function. */
if (sym)
{
! OBJ_SYMFIELD_TYPE *obj = symbol_get_obj (sym);
! expressionS *exp = xmalloc (sizeof (expressionS));
!
! obj->size = exp;
! exp->X_op = O_subtract;
! exp->X_add_symbol = symbol_temp_new_now ();
! exp->X_op_symbol = sym;
! exp->X_add_number = 0;
!
! cur_frame_data->func_end_sym = exp->X_add_symbol;
}
! cur_frame_data = NULL;
*input_line_pointer = name_end;
}
*************** s_alpha_mask (fp)
*** 4498,4504 ****
ecoff_directive_mask (0);
}
else
! discard_rest_of_line ();
}
static void
--- 4527,4571 ----
ecoff_directive_mask (0);
}
else
! {
! long val;
! offsetT offset;
!
! if (!cur_frame_data)
! {
! if (fp)
! as_warn (_(".fmask outside of .ent"));
! else
! as_warn (_(".mask outside of .ent"));
! discard_rest_of_line ();
! return;
! }
!
! if (get_absolute_expression_and_terminator (&val) != ',')
! {
! if (fp)
! as_warn (_("bad .fmask directive"));
! else
! as_warn (_("bad .mask directive"));
! --input_line_pointer;
! discard_rest_of_line ();
! return;
! }
!
! offset = get_absolute_expression ();
! demand_empty_rest_of_line ();
!
! if (fp)
! {
! cur_frame_data->fmask = val;
! cur_frame_data->fmask_offset = offset;
! }
! else
! {
! cur_frame_data->mask = val;
! cur_frame_data->mask_offset = offset;
! }
! }
}
static void
*************** s_alpha_frame (dummy)
*** 4508,4514 ****
if (ECOFF_DEBUGGING)
ecoff_directive_frame (0);
else
! discard_rest_of_line ();
}
static void
--- 4575,4610 ----
if (ECOFF_DEBUGGING)
ecoff_directive_frame (0);
else
! {
! long val;
!
! if (!cur_frame_data)
! {
! as_warn (_(".frame outside of .ent"));
! discard_rest_of_line ();
! return;
! }
!
! cur_frame_data->fp_regno = tc_get_register (1);
!
! SKIP_WHITESPACE ();
! if (*input_line_pointer++ != ','
! || get_absolute_expression_and_terminator (&val) != ',')
! {
! as_warn (_("bad .frame directive"));
! --input_line_pointer;
! discard_rest_of_line ();
! return;
! }
! cur_frame_data->frame_size = val;
!
! cur_frame_data->ra_regno = tc_get_register (0);
!
! /* Next comes the "offset of saved $a0 from $sp". In gcc terms
! this is current_function_pretend_args_size. There's no place
! to put this value, so ignore it. */
! s_ignore (42);
! }
}
static void
*************** s_alpha_prologue (ignore)
*** 4524,4530 ****
if (ECOFF_DEBUGGING)
sym = ecoff_get_cur_proc_sym ();
else
! sym = alpha_cur_ent_sym;
if (sym == NULL)
{
--- 4620,4626 ----
if (ECOFF_DEBUGGING)
sym = ecoff_get_cur_proc_sym ();
else
! sym = cur_frame_data ? cur_frame_data->func_sym : NULL;
if (sym == NULL)
{
*************** s_alpha_prologue (ignore)
*** 4549,4554 ****
--- 4645,4653 ----
as_bad (_("Invalid argument %d to .prologue."), arg);
break;
}
+
+ if (cur_frame_data)
+ cur_frame_data->prologue_sym = symbol_temp_new_now ();
}
static char *first_file_directive;
*************** s_alpha_coff_wrapper (which)
*** 4641,4646 ****
--- 4740,4826 ----
as_bad (_("ECOFF debugging is disabled."));
ignore_rest_of_line ();
}
+ }
+
+ /* Called at the end of assembly. Here we emit unwind info for frames
+ unless the compiler has done it for us. */
+
+ void
+ alpha_elf_md_end (void)
+ {
+ struct alpha_elf_frame_data *p;
+
+ if (cur_frame_data)
+ as_warn (_(".ent directive without matching .end"));
+
+ /* If someone has generated the unwind info themselves, great. */
+ if (bfd_get_section_by_name (stdoutput, ".eh_frame") != NULL)
+ return;
+
+ /* Generate .eh_frame data for the unwind directives specified. */
+ for (p = all_frame_data; p ; p = p->next)
+ if (p->prologue_sym)
+ {
+ /* Create a temporary symbol at the same location as our
+ function symbol. This prevents problems with globals. */
+ cfi_new_fde (symbol_temp_new (S_GET_SEGMENT (p->func_sym),
+ S_GET_VALUE (p->func_sym),
+ symbol_get_frag (p->func_sym)));
+
+ cfi_set_return_column (p->ra_regno);
+ cfi_add_CFA_def_cfa_register (30);
+ if (p->fp_regno != 30 || p->mask || p->fmask || p->frame_size)
+ {
+ unsigned int mask;
+ offsetT offset;
+
+ cfi_add_advance_loc (p->prologue_sym);
+
+ if (p->fp_regno != 30)
+ if (p->frame_size != 0)
+ cfi_add_CFA_def_cfa (p->fp_regno, p->frame_size);
+ else
+ cfi_add_CFA_def_cfa_register (p->fp_regno);
+ else if (p->frame_size != 0)
+ cfi_add_CFA_def_cfa_offset (p->frame_size);
+
+ mask = p->mask;
+ offset = p->mask_offset;
+
+ /* Recall that $26 is special-cased and stored first. */
+ if ((mask >> 26) & 1)
+ {
+ cfi_add_CFA_offset (26, offset);
+ offset += 8;
+ mask &= ~(1 << 26);
+ }
+ while (mask)
+ {
+ unsigned int i;
+ i = mask & -mask;
+ mask ^= i;
+ i = ffs (i) - 1;
+
+ cfi_add_CFA_offset (i, offset);
+ offset += 8;
+ }
+
+ mask = p->fmask;
+ offset = p->fmask_offset;
+ while (mask)
+ {
+ unsigned int i;
+ i = mask & -mask;
+ mask ^= i;
+ i = ffs (i) - 1;
+
+ cfi_add_CFA_offset (i + 32, offset);
+ offset += 8;
+ }
+ }
+
+ cfi_end_fde (p->func_end_sym);
+ }
}
#endif /* OBJ_ELF */
Index: config/tc-alpha.h
===================================================================
RCS file: /cvs/src/src/gas/config/tc-alpha.h,v
retrieving revision 1.16
diff -c -p -d -r1.16 tc-alpha.h
*** config/tc-alpha.h 7 Nov 2002 00:42:18 -0000 1.16
--- config/tc-alpha.h 30 May 2003 02:55:40 -0000
*************** extern flagword alpha_elf_section_flags
*** 128,133 ****
--- 128,138 ----
#define tc_frob_file_before_fix() alpha_before_fix ()
extern void alpha_before_fix PARAMS ((void));
+ #ifdef OBJ_ELF
+ #define md_end alpha_elf_md_end
+ extern void alpha_elf_md_end PARAMS ((void));
+ #endif
+
/* New fields for supporting explicit relocations (such as !literal to mark
where a pointer is loaded from the global table, and !lituse_base to track
all of the normal uses of that pointer). */
*************** do { \
*** 156,159 ****
(long) FIX->tc_fix_data.next_reloc); \
} while (0)
! #define DWARF2_LINE_MIN_INSN_LENGTH 4
--- 161,166 ----
(long) FIX->tc_fix_data.next_reloc); \
} while (0)
! #define DWARF2_LINE_MIN_INSN_LENGTH 4
! #define DWARF2_DEFAULT_RETURN_COLUMN 26
! #define DWARF2_CIE_DATA_ALIGNMENT -8
Index: testsuite/gas/alpha/elf-reloc-8.d
===================================================================
RCS file: /cvs/src/src/gas/testsuite/gas/alpha/elf-reloc-8.d,v
retrieving revision 1.1
diff -c -p -d -r1.1 elf-reloc-8.d
*** testsuite/gas/alpha/elf-reloc-8.d 7 Nov 2002 00:42:19 -0000 1.1
--- testsuite/gas/alpha/elf-reloc-8.d 30 May 2003 02:55:41 -0000
*************** OFFSET *TYPE *VALUE
*** 307,309 ****
--- 307,330 ----
0*0000048 REFQUAD \.init\.text\+0x0*00005f0
0*0000050 REFQUAD \.init\.data\+0x0*0000029
0*0000058 REFQUAD \.init\.text\+0x0*0000610
+
+
+ RELOCATION RECORDS FOR \[\.eh_frame\]:
+ OFFSET *TYPE *VALUE
+ 0*000001c SREL32 \.init\.text\+0xf*ffffff8
+ 0*0000034 SREL32 \.init\.text\+0x0*0000048
+ 0*0000048 SREL32 \.init\.text\+0x0*0000078
+ 0*000005c SREL32 \.init\.text\+0x0*00000a8
+ 0*0000080 SREL32 \.init\.text\+0x0*00002b8
+ 0*00000a0 SREL32 \.init\.text\+0x0*0000598
+ 0*00000b8 SREL32 \.init\.text\+0x0*00005e8
+ 0*00000cc SREL32 \.init\.text\+0x0*0000608
+ 0*00000e0 SREL32 \.init\.text\+0x0*0000628
+ 0*00000fc SREL32 \.init\.text\+0x0*0000748
+ 0*0000120 SREL32 \.init\.text\+0x0*0000988
+ 0*000013c SREL32 \.init\.text\+0x0*0000a08
+ 0*0000150 SREL32 \.init\.text\+0x0*0000a18
+ 0*0000164 SREL32 \.init\.text\+0x0*0000a38
+ 0*000017c SREL32 \.init\.text\+0x0*0000a88
+ 0*0000190 SREL32 \.init\.text\+0x0*0000a98
+ 0*00001a4 SREL32 \.text\+0xf*ffffff8
Index: testsuite/gas/cfi/cfi-alpha-1.d
===================================================================
RCS file: testsuite/gas/cfi/cfi-alpha-1.d
diff -N testsuite/gas/cfi/cfi-alpha-1.d
*** /dev/null 1 Jan 1970 00:00:00 -0000
--- testsuite/gas/cfi/cfi-alpha-1.d 30 May 2003 02:55:41 -0000
***************
*** 0 ****
--- 1,26 ----
+ #readelf: -wf
+ #name: CFI on alpha
+ The section .eh_frame contains:
+
+ 00000000 00000010 00000000 CIE
+ Version: 1
+ Augmentation: "zR"
+ Code alignment factor: 4
+ Data alignment factor: -8
+ Return address column: 26
+ Augmentation data: 1b
+
+ DW_CFA_def_cfa_reg: r30
+ DW_CFA_nop
+
+ 00000014 0000001c 00000018 FDE cie=00000000 pc=0000001c..00000050
+ DW_CFA_advance_loc: 24 to 00000034
+ DW_CFA_def_cfa: r15 ofs 32
+ DW_CFA_offset: r26 at cfa-32
+ DW_CFA_offset: r9 at cfa-24
+ DW_CFA_offset: r15 at cfa-16
+ DW_CFA_offset: r34 at cfa-8
+ DW_CFA_nop
+ DW_CFA_nop
+ DW_CFA_nop
+
Index: testsuite/gas/cfi/cfi-alpha-1.s
===================================================================
RCS file: testsuite/gas/cfi/cfi-alpha-1.s
diff -N testsuite/gas/cfi/cfi-alpha-1.s
*** /dev/null 1 Jan 1970 00:00:00 -0000
--- testsuite/gas/cfi/cfi-alpha-1.s 30 May 2003 02:55:41 -0000
***************
*** 0 ****
--- 1,28 ----
+ .file 1 "z.c"
+ .set noat
+ .set noreorder
+ .text
+ .align 4
+ .globl f
+ .ent f
+ $f..ng:
+ f:
+ .frame $15,32,$26,0
+ .mask 0x4008200,-32
+ .fmask 0x4,-8
+ lda $30,-32($30)
+ stq $26,0($30)
+ stq $9,8($30)
+ stq $15,16($30)
+ stt $f2,24($30)
+ mov $30,$15
+ .prologue 0
+ mov $15,$30
+ ldq $26,0($30)
+ ldq $9,8($30)
+ ldt $f2,24($30)
+ ldq $15,16($30)
+ lda $30,32($30)
+ ret $31,($26),1
+ .end f
+ .ident "GCC: (GNU) 2.96 20000731 (Red Hat Linux 7.2 2.96-112.7.1)"
Index: testsuite/gas/cfi/cfi.exp
===================================================================
RCS file: /cvs/src/src/gas/testsuite/gas/cfi/cfi.exp,v
retrieving revision 1.1
diff -c -p -d -r1.1 cfi.exp
*** testsuite/gas/cfi/cfi.exp 20 May 2003 08:01:19 -0000 1.1
--- testsuite/gas/cfi/cfi.exp 30 May 2003 02:55:41 -0000
*************** if [istarget "x86_64-*"] then {
*** 5,7 ****
--- 5,19 ----
if [istarget "i?86-*"] then {
run_dump_test "cfi-i386"
}
+
+ if { [istarget alpha*-*-*] } then {
+
+ set elf [expr [istarget *-*-elf*] \
+ || [istarget *-*-linux*] \
+ || [istarget *-*-freebsd*] \
+ || [istarget *-*-netbsd*] ]
+
+ if $elf {
+ run_dump_test "cfi-alpha-1"
+ }
+ }
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