We have two stacks to deal with on ia64, when making a function call.
The first is the usual stack frame, and the second is the register
stack frame. On ia64-linux, the register frame is setup by adjusting
the BSP register. Unfortunately for us, the HP-UX kernel does not allow
the debugger to change the value of the BSP.
To work around that limitation, the method I am using here is to push
some assembly code on the stack. This assembly code contains, among
other things, a call to the alloc insn, which sets up our frame for us.
An extensive comment in ia64-hpux-tdep.c explains the entire procedure.
Despite this approach, most of the code in ia64-tdep.c which sets up
the function call is still applicable - and only a few things need
to be done differently: For instance, instead of changing the BSP,
we do nothing. We store the parameters at a different location, etc.
So this patch also adjusts the inf-call code in ia64-tdep.c to make it
a little more extensible: I create a new ia64_infcall_ops structure
which allows an ABI to define how the few things that need to be
differentiated.
Another element that turned out to be necessary but is more of a detail
is that the computation of the linkage pointer needs to be handled
specially for symbols inside shared libraries. This is especially
visible when calling malloc, which happens everytime memory needs to
be allocated in inferior memory... The special treatment included
again the necessity to use some routines only available on the host.
So another target object TARGET_OBJECT_HPUX_SOLIB_GOT was created for
that purpose.
gdb/ChangeLog:
* ia64-tdep.h (struct regcache): Forward declare.
(struct ia64_infcall_ops): New struct type.
(struct gdbarch_tdep): New fields "find_global_pointer_from_solib"
and "infcall_ops".
* ia64-tdep.c (ia64_find_global_pointer_from_dynamic_section):
Renames ia64_find_global_pointer.
(ia64_find_global_pointer, ia64_allocate_new_rse_frame)
(ia64_store_argument_in_slot, ia64_set_function_addr: New function.
(ia64_push_dummy_call): Adjust to use the new tdep ia64_infocall_ops
methods.
(ia64_infcall_ops): New static global constant.
(ia64_gdbarch_init): Set tdep->infcall_ops.
* ia64-hpux-nat.c (ia64_hpux_xfer_solib_got): New function.
(ia64_hpux_xfer_partial): Add TARGET_OBJECT_HPUX_SOLIB_GOT handing.
* ia64-hpux-tdep.c: Include "regcache.h", "gdbcore.h" and "inferior.h".
(ia64_hpux_dummy_code): New static global constant.
(ia64_hpux_push_dummy_code, ia64_hpux_allocate_new_rse_frame)
(ia64_hpux_store_argument_in_slot, ia64_hpux_set_function_addr)
(ia64_hpux_dummy_id, ia64_hpux_find_global_pointer_from_solib):
New function.
(ia64_hpux_infcall_ops): New static global constant.
(ia64_hpux_init_abi): Install gdbarch and tdep methods needed
for inferior function calls to work properly on ia64-hpux.
This fixes unwinding from a thread that is stopped inside a system call.
This can be seen when switching to a thread that is stopped doing a
pthread_cond_wait, for instance...
The comments inside the code should explain what is happening in our
case (the HP-UX exception in the case of system calls): Under certain
circumstances (program stopped inside syscall), the offset to apply to
the current BSP in order to compute the previous BSP is not the usual
CFM & 0x7f.
We parts in this patch:
1. Figuring out that we are stopped inside a syscal: This requires
a TT_LWP_RUREGS ttrace call, which is not directly possible from
ia64-tdep.c. So use defined a new TARGET_OBJECT_HPUX_UREGS object
to request it from the -nat side.
2. Add a gdbarch_tdep method that allows us to change the default
behavior on ia64-hpux, permitting us to have a different "size of
register frame" in that one particular case.
gdb/ChangeLog:
* target.h (enum target_object): Add TARGET_OBJECT_HPUX_UREGS.
* ia64-tdep.h (struct frame_info): forward declaration.
(struct gdbarch_tdep): Add field size_of_register_frame.
* ia64-tdep.c (ia64_access_reg): Use tdep->size_of_register_frame
to determine the size of the register frame.
(ia64_size_of_register_frame): New function.
(ia64_gdbarch_init): Set tdep->size_of_register_frame.
* ia64-hpux-tdep.c: Include "target.h" and "frame.h".
(IA64_HPUX_UREG_REASON): New macro.
(ia64_hpux_stopped_in_syscall, ia64_hpux_size_of_register_frame):
New functions.
(ia64_hpux_init_abi): Set tdep->size_of_register_frame.
* ia64-hpux-nat.c (ia64_hpux_xfer_uregs): New function.
(ia64_hpux_xfer_partial): Add handling of TARGET_OBJECT_HPUX_UREGS
objects.
This patch fixes a small problem on ia64-hpux when calling functions
whose parameter are small integral values (less than 8 bytes). In
that case, the parameter value was stored on the wrong side of the
register. Same problem for return values.
With this patch, the results for gdb.base/callfuncs.exp improve from
# of expected passes 41
# of unexpected failures 78
To:
# of expected passes 95
# of unexpected failures 24
gdb/ChangeLog:
* ia64-tdep.c (ia64_struct_type_p): New function.
(ia64_extract_return_value): Handle integral values that are
less than 8 bytes long.
(ia64_push_dummy_call): Likewise.
ia64-tdep.c defines a floatformats_ia64_ext that should contain
both the little-endian and the big-endian version of the float
format used in the ia64 registers (an 82bit float format).
Right now, both entries point to the same little-endian definition.
A big-endian definition is now necessary for the ia64-hpux port.
gdb/ChangeLog:
* ia64-tdep.c (floatformat_ia64_ext_little): Renames
floatformat_ia64_ext.
(floatformat_ia64_ext_big): New static const.
(floatformats_ia64_ext): Set first entry to &floatformat_ia64_ext_big.
* ia64-tdep.c (ia64_memory_insert_breakpoint): Extend the comment.
New variable shadow_slotnum, use it appropriately instead of slotnum.
Move shadow_len initialization before SLOTNUM adjustment, cover now the
whole remaining bundle. Error now on breakpoints requested for the
slot 2 of L-X bundles. Better sanity check the requested slot 1 of L-X
bundles.
(ia64_memory_remove_breakpoint): New variable shadow_slotnum, use it
appropriately instead of slotnum. Warn now on breakpoints requested
for the slot 2 of L-X bundles. Better sanity check the requested slot
1 of L-X bundles. Update the assertio check of PLACED_SIZE.
(ia64_breakpoint_from_pc): New variable shadow_slotnum, use it
appropriately instead of slotnum. Move *lenptr initialization before
SLOTNUM adjustment, cover now the whole remaining bundle. Error now
on breakpoints requested for the slot 2 of L-X bundles. Better sanity
check the requested slot 1 of L-X bundles. Simplify the returned
expression.
* frame.c (get_frame_id): Default to outer_frame_id if the this_id
method does not supply an ID. Assert that the result is not
null_frame_id.
(outer_frame_id): New.
(frame_id_p): Accept outer_frame_id.
(frame_id_eq): Allow outer_frame_id to be equal to itself.
(frame_find_by_id): Revert previous local workarounds.
(get_prev_frame_1): Adjust end-of-stack check to test outer_frame_id.
* frame.h (null_frame_id, frame_id_p): Update comments.
(outer_frame_id): Declare.
* infrun.c (handle_inferior_event): Do not treat all steps from the
outermost frame as subroutine calls.
* libunwind-frame.c (libunwind_frame_this_id): Do not clear THIS_ID.
* hppa-tdep.c (hppa_stub_frame_this_id): Likewise.
* ia64-tdep.c (ia64_frame_this_id): Likewise.
(ia64_libunwind_frame_this_id, ia64_libunwind_sigtramp_frame_this_id):
Use outer_frame_id instead of null_frame_id.
* amd64obsd-tdep.c (amd64obsd_trapframe_cache): Use outer_frame_id.
* i386obsd-tdep.c (i386obsd_trapframe_cache): Likewise.
* inline-frame.c (inline_frame_this_id): Refuse outer_frame_id.
* thread.c (restore_selected_frame): Update comment and remove
frame_id_p check.
gdb/doc/
* gdbint.texinfo (Unwinding the Frame ID): Reference outer_frame_id.
* ia64-tdep.c (ia64_memory_insert_breakpoint)
(ia64_memory_remove_breakpoint): Return immediately if any of memory
reads fail. Do not combine the VAL values.
Fix ia64 shadowing of breakpoints in multiple slots of a single bundle.
* ia64-tdep.c (ia64_memory_insert_breakpoint): New call
of make_show_memory_breakpoints_cleanup with parameter 0. Move the
reading of SHADOW_CONTENTS to this memory state point of code. Update
comment for the memory re-read.
gdb/testsuite/
* gdb.base/breakpoint-shadow.exp (Second breakpoint placed): Initialize
$bpt2address.
(Second breakpoint address is valid on ia64)
(Third breakpoint on ia64 in the Second breakpoint's bundle): New.
Fix ia64 start crash when GDB built with -lmcheck.
* ia64-tdep.c (ia64_gdbarch_init): Allocate TDEP as cleared. Remove
specific clearing of TDEP SIGCONTEXT_REGISTER_ADDRESS and
PC_IN_SIGTRAMP.
* ia64-tdep.c: New #if check on BREAKPOINT_MAX vs. BUNDLE_LEN.
(ia64_memory_insert_breakpoint): New comment part for SHADOW_CONTENTS
content. Remove variable instr. New variable cleanup. Force
automatic breakpoints restoration. PLACED_SIZE and SHADOW_LEN are now
set larger, to BUNDLE_LEN - 2. Variable `bundle' type update. Return
error if even just final target_write_memory has failed.
(ia64_memory_remove_breakpoint): Rename variables bundle to bundle_mem
and instr to instr_saved. New variables bundle_saved and
instr_breakpoint. Comment new reasons why we need to disable automatic
restoration of breakpoints. Assert PLACED_SIZE and SHADOW_LEN. New
check of the original memory content. Return error if even just final
target_write_memory has failed.
(ia64_breakpoint_from_pc): Implement the emulation of permanent
breakpoints compatible with current bp_loc_is_permanent.
(template_encoding_table): Make it `const'.
* breakpoint.c (bp_loc_is_permanent): Support unsupported software
breakpoints. New variables `cleanup' and `retval'.
* monitor.c (monitor_insert_breakpoint): Remove unused variable `bp'.
Change argument of pulongest from CORE_ADDR to ULONGEST.
All callers updated.
* utils.c (plongest): Renamed from paddr_d.
(pulongest): Renamed from paddr_u, change arg type to ULONGEST.
* remote-mips.c (send_srec): Use paddr_nz instead of paddr_u in
`CORE_ADDR addr' arg of error message.
(amd64_init_abi): Use i387_convert_register_p.
* alpha-tdep.c (alpha_convert_register_p): Return zero for
eight byte types.
(alpha_register_to_value, alpha_value_to_register): Do not handle
eight byte types.
* i386-tdep.c (i386_convert_register_p): Use i387_convert_register_p.
* i387-tdep.c (i387_convert_register_p): New.
(i387_register_to_value, i387_value_to_register): Update comments.
* i387-tdep.h (i387_convert_register_p): Declare.
* ia64-tdep.c (ia64_convert_register_p): Return zero for
builtin_type_ia64_ext.
(ia64_gdbarch_init): Do not initialize builtin_type_ia64_ext here.
(_initialize_ia64_tdep): Initialize builtin_type_ia64_ext here.
* m68k-tdep.c (m68k_convert_register_p): Return zero for
builtin_type_m68881_ext.
(m68k_register_to_value, m68k_value_to_register): Update comments.
* gdbint.texinfo (Register and Memory Data, Target Conditionals):
Document that gdbarch_convert_register_p should return zero for no-op
conversions.
(avr_gdbarch_init): Call set_gdbarch_return_value instead of
set_gdbarch_extract_return_value.
* fvr-tdep.c (frv_return_value): New function.
(frv_gdbarch_init): Call set_gdbarch_return_value instead of
set_gdbarch_extract_return_value, set_gdbarch_store_return_value,
and set_gdbarch_deprecated_use_struct_convention.
* ia64-tdep.c (ia64_use_struct_convention): Make static.
Add check for structure, union, or array types.
(ia64_extract_return_value): Make static.
(ia64_store_return_value): Make static. Support multi-word values.
(ia64_return_value): New function.
(ia64_gdbarch_init): Call set_gdbarch_return_value instead of
set_gdbarch_extract_return_value, set_gdbarch_store_return_value,
and set_gdbarch_deprecated_use_struct_convention.
