espressif/binutils-gdb
1
0
Fork 0
mirror of https://github.com/espressif/binutils-gdb.git synced 2025-05-31 18:20:12 +08:00
Code Issues Packages Projects Releases Wiki Activity

PowerPC __tls_get_addr arg parsing

Browse Source 
The syntax we ended up with for -m32 -fPIC calls to __tls_get_addr is
rather weird.
    bl __tls_get_addr+0x8000(gd0@tlsgd)@plt
This came about by accident, probably due to requiring the arg reloc
before the call reloc.

Of course the @plt really belongs with __tls_get_addr since it affects
the call rather than the call arg, and it isn't a great deal of
trouble to ensure the relocs are emitted in the correct order.  This
patch supports a newer syntax, like so:
    bl __tls_get_addr+0x8000@plt(gd0@tlsgd)

gas/
	* config/tc-ppc.c (parse_tls_arg): New function, extracted..
	(md_assembler): ..from here.  Call it after parsing other
	suffix modifiers too.
ld/
	* testsuite/ld-powerpc/tls32.s: Test new @plt syntax.
This commit is contained in:
Alan Modra
2019-02-21 17:41:47 +10:30
parent 56b80d4c4c
commit 160eba9301
2 changed files with 54 additions and 41 deletions
Download Patch File Download Diff File Expand all files Collapse all files

92
gas/config/tc-ppc.c
View File

@ -2999,6 +2999,43 @@ fixup_size (bfd_reloc_code_real_type reloc, bfd_boolean *pc_relative)
return size;
}
/* If we have parsed a call to __tls_get_addr, parse an argument like
(gd0@tlsgd). *STR is the leading parenthesis on entry. If an arg
is successfully parsed, *STR is updated past the trailing
parenthesis and trailing white space, and *TLS_FIX contains the
reloc and arg expression. */
static int
parse_tls_arg (char **str, const expressionS *exp, struct ppc_fixup *tls_fix)
{
const char *sym_name = S_GET_NAME (exp->X_add_symbol);
if (sym_name[0] == '.')
++sym_name;
tls_fix->reloc = BFD_RELOC_NONE;
if (strcasecmp (sym_name, "__tls_get_addr") == 0)
{
char *hold = input_line_pointer;
input_line_pointer = *str + 1;
expression (&tls_fix->exp);
if (tls_fix->exp.X_op == O_symbol)
{
if (strncasecmp (input_line_pointer, "@tlsgd)", 7) == 0)
tls_fix->reloc = BFD_RELOC_PPC_TLSGD;
else if (strncasecmp (input_line_pointer, "@tlsld)", 7) == 0)
tls_fix->reloc = BFD_RELOC_PPC_TLSLD;
if (tls_fix->reloc != BFD_RELOC_NONE)
{
input_line_pointer += 7;
SKIP_WHITESPACE ();
*str = input_line_pointer;
}
}
input_line_pointer = hold;
}
return tls_fix->reloc != BFD_RELOC_NONE;
}
/* This routine is called for each instruction to be assembled. */
void
@ -3388,47 +3425,12 @@ md_assemble (char *str)
{
bfd_reloc_code_real_type reloc = BFD_RELOC_NONE;
#ifdef OBJ_ELF
if (ex.X_op == O_symbol && str[0] == '(')
/* Look for a __tls_get_addr arg using the insane old syntax. */
if (ex.X_op == O_symbol && *str == '(' && fc < MAX_INSN_FIXUPS
&& parse_tls_arg (&str, &ex, &fixups[fc]))
{
const char *sym_name = S_GET_NAME (ex.X_add_symbol);
if (sym_name[0] == '.')
++sym_name;
if (strcasecmp (sym_name, "__tls_get_addr") == 0)
{
expressionS tls_exp;
hold = input_line_pointer;
input_line_pointer = str + 1;
expression (&tls_exp);
if (tls_exp.X_op == O_symbol)
{
reloc = BFD_RELOC_NONE;
if (strncasecmp (input_line_pointer, "@tlsgd)", 7) == 0)
{
reloc = BFD_RELOC_PPC_TLSGD;
input_line_pointer += 7;
}
else if (strncasecmp (input_line_pointer, "@tlsld)", 7) == 0)
{
reloc = BFD_RELOC_PPC_TLSLD;
input_line_pointer += 7;
}
if (reloc != BFD_RELOC_NONE)
{
SKIP_WHITESPACE ();
str = input_line_pointer;
if (fc >= MAX_INSN_FIXUPS)
as_fatal (_("too many fixups"));
fixups[fc].exp = tls_exp;
fixups[fc].opindex = *opindex_ptr;
fixups[fc].reloc = reloc;
++fc;
}
}
input_line_pointer = hold;
}
fixups[fc].opindex = *opindex_ptr;
++fc;
}
if ((reloc = ppc_elf_suffix (&str, &ex)) != BFD_RELOC_NONE)
@ -3703,6 +3705,16 @@ md_assemble (char *str)
break;
}
}
/* Look for a __tls_get_addr arg after any __tls_get_addr
modifiers like @plt. This fixup must be emitted before
the usual call fixup. */
if (ex.X_op == O_symbol && *str == '(' && fc < MAX_INSN_FIXUPS
&& parse_tls_arg (&str, &ex, &fixups[fc]))
{
fixups[fc].opindex = *opindex_ptr;
++fc;
}
#endif
/* We need to generate a fixup for this expression. */

3
ld/testsuite/ld-powerpc/tls32.s
View File

@ -62,7 +62,8 @@ _start:
#LD
addi 3,31,ld0@got@tlsld #R_PPC_GOT_TLSLD16 ld0
.ifdef TLSMARK
bl __tls_get_addr+0x8000(ld0@tlsld)@plt #R_PPC_TLSLD ld0
#exercise saner new syntax with @plt before the arg
bl __tls_get_addr+0x8000@plt(ld0@tlsld) #R_PPC_TLSLD ld0
#R_PPC_PLTREL24 __tls_get_addr+0x8000
.else
bl __tls_get_addr+0x8000@plt #R_PPC_PLTREL24 __tls_get_addr+0x8000