From 02660e8c4bd2ee15517d33712a0cd632e521a066 Mon Sep 17 00:00:00 2001 From: Jim Blandy Date: Fri, 13 Jun 2003 19:58:44 +0000 Subject: Revert change for revision. --- gdb/ppc-linux-tdep.c | 102 --------------------------------------------------- 1 file changed, 102 deletions(-) diff --git a/gdb/ppc-linux-tdep.c b/gdb/ppc-linux-tdep.c index 6ee0e5a5f08..7e6306e821b 100644 --- a/gdb/ppc-linux-tdep.c +++ b/gdb/ppc-linux-tdep.c @@ -941,106 +941,6 @@ ppc64_call_dummy_address (void) } -/* Return the unrelocated code address at which execution begins for - ABFD, under the 64-bit PowerPC Linux ABI. On that system, the ELF - header e_entry field (which is what bfd_get_start_address gives - you) is the address of the function descriptor for the startup - function, not the address of the actual machine instruction you - jump to. - - This function doesn't just go and read the entry point from the - function descriptor. We need it to work when ABFD is the dynamic - linker, immediately after an exec. But ld.so is a dynamic - executable itself on PPC64 Linux, so it appears in memory whereever - the kernel drops it; this means that bfd_get_start_address's result - needs to be adjusted --- by some offset we don't know. So we can't - find the descriptor's address in memory to read the entry point - from it. - - Instead, we do it all based on ABFD's symbol table. We take the - address from bfd_get_start_address, find each symbol at that - address, stick a '.' on the front of its name to get the entry - point symbol name, try to look that up, and return the value of - what we find, if anything. We never touch memory, or talk with the - kernel about the inferior at all. - - Now, this address we return is straight from the symbol table, so - it hasn't been adjusted to take into account where ABFD was loaded. - But that's okay --- our job is just to return the unrelocated code - address. */ -static CORE_ADDR -ppc64_linux_bfd_entry_point (struct gdbarch *gdbarch, bfd *abfd) -{ - long storage_needed; - - storage_needed = bfd_get_symtab_upper_bound (abfd); - - if (storage_needed > 0) - { - asymbol **symbol_table; - unsigned int symbol_table_len; - struct cleanup *back_to; - unsigned int i; - CORE_ADDR start_address; - - symbol_table = (asymbol **) xmalloc (storage_needed); - back_to = make_cleanup (xfree, symbol_table); - symbol_table_len = bfd_canonicalize_symtab (abfd, symbol_table); - - /* Find the symbol naming the start function's descriptor. Its - value must be the BFD's start address, and it must be in a - data section. - - Also, the symbol's name must be non-empty. A lot of symtabs - seem to contain a bunch of symbols with no name whose value - is zero relative to the start of the data section; if the - start function descriptor is the first thing in the data - section, we'll get more false positives than we'd like. */ - start_address = bfd_get_start_address (abfd); - for (i = 0; i < symbol_table_len; i++) - if (bfd_asymbol_value (symbol_table[i]) == start_address - && symbol_table[i]->section->flags & SEC_DATA - && bfd_asymbol_name (symbol_table[i])[0] != '\0') - { - /* Okay, we've found a symbol whose value and section are - right. Construct the name of the corresponding entry - point symbol and see if we can find a symbol with that - name in a code section. */ - const char *desc_name = bfd_asymbol_name (symbol_table[i]); - char *entry_pt_name = alloca (strlen (desc_name) + 2); - int j; - - entry_pt_name[0] = '.'; - strcpy (entry_pt_name + 1, desc_name); - - for (j = 0; j < symbol_table_len; j++) - if ((strcmp (bfd_asymbol_name (symbol_table[j]), entry_pt_name) - == 0) - && symbol_table[j]->section->flags & SEC_CODE) - /* Yay! What a coincidence. Let's assume this is the - entry point symbol. */ - { - CORE_ADDR entry_point = bfd_asymbol_value (symbol_table[j]); - do_cleanups (back_to); - return entry_point; - } - - /* No good --- there's no symbol by that name. Perhaps - symbol_table[i] is just coincidentally equal to the - start address; after all, there could be many symbols - with the same value. Continue the search. */ - } - - /* No good --- there's no symbol pointing at the start - address. */ - do_cleanups (back_to); - } - - /* No good --- this BFD has no symbols at all. We give up! */ - return 0; -} - - enum { ELF_NGREG = 48, ELF_NFPREG = 33, @@ -1168,8 +1068,6 @@ ppc_linux_init_abi (struct gdbarch_info info, (gdbarch, ppc64_linux_convert_from_func_ptr_addr); set_gdbarch_call_dummy_address (gdbarch, ppc64_call_dummy_address); - - set_gdbarch_bfd_entry_point (gdbarch, ppc64_linux_bfd_entry_point); set_gdbarch_in_solib_call_trampoline (gdbarch, ppc64_in_solib_call_trampoline); -- cgit v1.2.1