char data[4];
} stepBreaks[2];
-/* Static function prototypes */
+/* Hook for determining the TOC address when calling functions in the
+ inferior under AIX. The initialization code in rs6000-nat.c sets
+ this hook to point to find_toc_address. */
+
+CORE_ADDR (*find_toc_address_hook) PARAMS ((CORE_ADDR)) = NULL;
-static CORE_ADDR find_toc_address PARAMS ((CORE_ADDR pc));
+/* Static function prototypes */
static CORE_ADDR branch_dest PARAMS ((int opcode, int instr, CORE_ADDR pc,
CORE_ADDR safety));
ext_op = (instr>>1) & 0x3ff;
if (ext_op == 16) /* br conditional register */
- dest = read_register (LR_REGNUM) & ~3;
+ {
+ dest = read_register (LR_REGNUM) & ~3;
+
+ /* If we are about to return from a signal handler, dest is
+ something like 0x3c90. The current frame is a signal handler
+ caller frame, upon completion of the sigreturn system call
+ execution will return to the saved PC in the frame. */
+ if (dest < TEXT_SEGMENT_BASE)
+ {
+ struct frame_info *fi;
+
+ fi = get_current_frame ();
+ if (fi != NULL)
+ dest = read_memory_integer (fi->frame + SIG_FRAME_PC_OFFSET,
+ 4);
+ }
+ }
else if (ext_op == 528) /* br cond to count reg */
{
int ii;
CORE_ADDR target_addr;
- CORE_ADDR tocvalue;
- target_addr = fun;
- tocvalue = find_toc_address (target_addr);
+ if (find_toc_address_hook != NULL)
+ {
+ CORE_ADDR tocvalue;
- ii = *(int*)((char*)dummyname + TOC_ADDR_OFFSET);
- ii = (ii & 0xffff0000) | (tocvalue >> 16);
- *(int*)((char*)dummyname + TOC_ADDR_OFFSET) = ii;
+ tocvalue = (*find_toc_address_hook) (fun);
+ ii = *(int*)((char*)dummyname + TOC_ADDR_OFFSET);
+ ii = (ii & 0xffff0000) | (tocvalue >> 16);
+ *(int*)((char*)dummyname + TOC_ADDR_OFFSET) = ii;
- ii = *(int*)((char*)dummyname + TOC_ADDR_OFFSET+4);
- ii = (ii & 0xffff0000) | (tocvalue & 0x0000ffff);
- *(int*)((char*)dummyname + TOC_ADDR_OFFSET+4) = ii;
+ ii = *(int*)((char*)dummyname + TOC_ADDR_OFFSET+4);
+ ii = (ii & 0xffff0000) | (tocvalue & 0x0000ffff);
+ *(int*)((char*)dummyname + TOC_ADDR_OFFSET+4) = ii;
+ }
+ target_addr = fun;
ii = *(int*)((char*)dummyname + TARGET_ADDR_OFFSET);
ii = (ii & 0xffff0000) | (target_addr >> 16);
*(int*)((char*)dummyname + TARGET_ADDR_OFFSET) = ii;
CORE_ADDR func_start;
struct rs6000_framedata fdata;
- if (fi->next != NULL)
- /* Don't even think about framelessness except on the innermost frame. */
- /* FIXME: Can also be frameless if fi->next->signal_handler_caller (if
- a signal happens while executing in a frameless function). */
+ /* Don't even think about framelessness except on the innermost frame
+ or if the function was interrupted by a signal. */
+ if (fi->next != NULL && !fi->next->signal_handler_caller)
return 0;
- func_start = get_pc_function_start (fi->pc) + FUNCTION_START_OFFSET;
+ func_start = get_pc_function_start (fi->pc);
/* If we failed to find the start of the function, it is a mistake
to inspect the instructions. */
if (!func_start)
- return 0;
+ {
+ /* A frame with a zero PC is usually created by dereferencing a NULL
+ function pointer, normally causing an immediate core dump of the
+ inferior. Mark function as frameless, as the inferior has no chance
+ of setting up a stack frame. */
+ if (fi->pc == 0)
+ return 1;
+ else
+ return 0;
+ }
+ func_start += FUNCTION_START_OFFSET;
(void) skip_prologue (func_start, &fdata);
return fdata.frameless;
}
(void) skip_prologue (func_start, &fdata);
if (fdata.lr_offset == 0 && fi->next != NULL)
- return read_memory_integer (rs6000_frame_chain (fi) + DEFAULT_LR_SAVE, 4);
+ {
+ if (fi->next->signal_handler_caller)
+ return read_memory_integer (fi->next->frame + SIG_FRAME_LR_OFFSET, 4);
+ else
+ return read_memory_integer (rs6000_frame_chain (fi) + DEFAULT_LR_SAVE,
+ 4);
+ }
if (fdata.lr_offset == 0)
return read_register (LR_REGNUM);
return 0;
if (thisframe->signal_handler_caller)
fp = read_memory_integer (thisframe->frame + SIG_FRAME_FP_OFFSET, 4);
+ else if (thisframe->next != NULL
+ && thisframe->next->signal_handler_caller
+ && frameless_function_invocation (thisframe))
+ /* A frameless function interrupted by a signal did not change the
+ frame pointer. */
+ fp = FRAME_FP (thisframe);
else
fp = read_memory_integer ((thisframe)->frame, 4);
return fp;
}
\f
-/* Keep an array of load segment information and their TOC table addresses.
- This info will be useful when calling a shared library function by hand. */
-
-struct loadinfo {
- CORE_ADDR textorg, dataorg;
- unsigned long toc_offset;
-};
-
-#define LOADINFOLEN 10
-
-static struct loadinfo *loadinfo = NULL;
-static int loadinfolen = 0;
-static int loadinfotocindex = 0;
-static int loadinfotextindex = 0;
-
-
-void
-xcoff_init_loadinfo ()
-{
- loadinfotocindex = 0;
- loadinfotextindex = 0;
-
- if (loadinfolen == 0) {
- loadinfo = (struct loadinfo *)
- xmalloc (sizeof (struct loadinfo) * LOADINFOLEN);
- loadinfolen = LOADINFOLEN;
- }
-}
-
-
-/* FIXME -- this is never called! */
-#if 0
-void
-free_loadinfo ()
-{
- if (loadinfo)
- free (loadinfo);
- loadinfo = NULL;
- loadinfolen = 0;
- loadinfotocindex = 0;
- loadinfotextindex = 0;
-}
-#endif
-
-/* this is called from xcoffread.c */
-
-void
-xcoff_add_toc_to_loadinfo (tocoff)
- unsigned long tocoff;
-{
- while (loadinfotocindex >= loadinfolen) {
- loadinfolen += LOADINFOLEN;
- loadinfo = (struct loadinfo *)
- xrealloc (loadinfo, sizeof(struct loadinfo) * loadinfolen);
- }
- loadinfo [loadinfotocindex++].toc_offset = tocoff;
-}
-
-void
-add_text_to_loadinfo (textaddr, dataaddr)
- CORE_ADDR textaddr;
- CORE_ADDR dataaddr;
-{
- while (loadinfotextindex >= loadinfolen) {
- loadinfolen += LOADINFOLEN;
- loadinfo = (struct loadinfo *)
- xrealloc (loadinfo, sizeof(struct loadinfo) * loadinfolen);
- }
- loadinfo [loadinfotextindex].textorg = textaddr;
- loadinfo [loadinfotextindex].dataorg = dataaddr;
- ++loadinfotextindex;
-}
-
-
-/* Note that this assumes that the "textorg" and "dataorg" elements of
- a member of this array are correlated with the "toc_offset" element
- of the same member. This is taken care of because the loops which
- assign the former (in xcoff_relocate_symtab or xcoff_relocate_core)
- and the latter (in scan_xcoff_symtab, via vmap_symtab, in
- vmap_ldinfo or xcoff_relocate_core) traverse the same objfiles in
- the same order. */
-
-static CORE_ADDR
-find_toc_address (pc)
- CORE_ADDR pc;
-{
- int ii, toc_entry;
- CORE_ADDR tocbase = 0;
-
- toc_entry = -1;
- for (ii=0; ii < loadinfotextindex; ++ii)
- if (pc > loadinfo[ii].textorg && loadinfo[ii].textorg > tocbase) {
- toc_entry = ii;
- tocbase = loadinfo[ii].textorg;
- }
-
- if (toc_entry == -1)
- error ("Unable to find TOC entry for pc 0x%x\n", pc);
- return loadinfo[toc_entry].dataorg + loadinfo[toc_entry].toc_offset;
-}
-
/* Return nonzero if ADDR (a function pointer) is in the data space and
is therefore a special function pointer. */
void
_initialize_rs6000_tdep ()
{
-#ifndef ELF_OBJECT_FORMAT
- {
- extern void (*xcoff_add_toc_to_loadinfo_hook) PARAMS ((unsigned long));
- extern void (*xcoff_init_loadinfo_hook) PARAMS ((void));
-
- /* Initialize hook in xcoffread for recording the toc offset value
- of a symbol table into the ldinfo structure, for native rs6000
- config. */
- xcoff_add_toc_to_loadinfo_hook = &xcoff_add_toc_to_loadinfo;
-
- /* Initialize hook in xcoffread for calling xcoff_init_loadinfo in
- a native rs6000 config. */
- xcoff_init_loadinfo_hook = &xcoff_init_loadinfo;
- }
-#endif /* ELF_OBJECT_FORMAT */
-
/* FIXME, this should not be decided via ifdef. */
#ifdef GDB_TARGET_POWERPC
tm_print_insn = gdb_print_insn_powerpc;