* ppc-linux-tdep.c (ppc64_linux_convert_from_func_ptr_addr): New

function.
(ppc_linux_init_abi): Register it as the
CONVERT_FROM_FUNC_PTR_ADDR method under the PPC64 Linux ABI.
This commit is contained in:
Jim Blandy 2003-06-24 23:06:04 +00:00
parent e716d87a00
commit 02631ec09e
2 changed files with 45 additions and 0 deletions

View file

@ -1,5 +1,10 @@
2003-06-24 Jim Blandy <jimb@redhat.com>
* ppc-linux-tdep.c (ppc64_linux_convert_from_func_ptr_addr): New
function.
(ppc_linux_init_abi): Register it as the
CONVERT_FROM_FUNC_PTR_ADDR method under the PPC64 Linux ABI.
* ppc-linux-tdep.c (ppc64_call_dummy_address): New function.
(ppc_linux_init_abi): Set it as the gdbarch's call_dummy_address
method.

View file

@ -894,6 +894,41 @@ ppc64_skip_trampoline_code (CORE_ADDR pc)
}
/* Support for CONVERT_FROM_FUNC_PTR_ADDR(ADDR) on PPC64 Linux.
Usually a function pointer's representation is simply the address
of the function. On Linux on the 64-bit PowerPC however, a function
pointer is represented by a pointer to a TOC entry. This TOC entry
contains three words, the first word is the address of the
function, the second word is the TOC pointer (r2), and the third
word is the static chain value. Throughout GDB it is currently
assumed that a function pointer contains the address of the
function, which is not easy to fix. In addition, the conversion of
a function address to a function pointer would require allocation
of a TOC entry in the inferior's memory space, with all its
drawbacks. To be able to call C++ virtual methods in the inferior
(which are called via function pointers), find_function_addr uses
this function to get the function address from a function
pointer. */
/* Return real function address if ADDR (a function pointer) is in the data
space and is therefore a special function pointer. */
static CORE_ADDR
ppc64_linux_convert_from_func_ptr_addr (CORE_ADDR addr)
{
struct obj_section *s;
s = find_pc_section (addr);
if (s && s->the_bfd_section->flags & SEC_CODE)
return addr;
/* ADDR is in the data space, so it's a pointer to a descriptor, not
the entry point. */
return ppc64_desc_entry_point (addr);
}
/* On 64-bit PowerPC Linux, the ELF header's e_entry field is the
address of a function descriptor for the entry point function, not
the actual entry point itself. So to find the actual address at
@ -1027,6 +1062,11 @@ ppc_linux_init_abi (struct gdbarch_info info,
if (tdep->wordsize == 8)
{
/* Handle PPC64 Linux function pointers (which are really
function descriptors). */
set_gdbarch_convert_from_func_ptr_addr
(gdbarch, ppc64_linux_convert_from_func_ptr_addr);
set_gdbarch_call_dummy_address (gdbarch, ppc64_call_dummy_address);
set_gdbarch_in_solib_call_trampoline