From 1ce5d6dda58437d73491c1dda90dbdd48e37e142 Mon Sep 17 00:00:00 2001 From: Andrew Cagney Date: Fri, 18 Jul 2003 19:59:27 +0000 Subject: [PATCH] 2003-07-18 Andrew Cagney * dwarf2-frame.c (dwarf2_frame_sniffer): Use frame_unwind_address_in_block, instead of frame_pc_unwind. (dwarf2_frame_cache): Ditto. --- gdb/ChangeLog | 6 ++++++ gdb/dwarf2-frame.c | 29 +++++++++++------------------ 2 files changed, 17 insertions(+), 18 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index eeb0b7a6dd7..572457448cc 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,9 @@ +2003-07-18 Andrew Cagney + + * dwarf2-frame.c (dwarf2_frame_sniffer): Use + frame_unwind_address_in_block, instead of frame_pc_unwind. + (dwarf2_frame_cache): Ditto. + 2003-07-18 Andrew Cagney * user-regs.h (struct gdbarch): Declare opaque. diff --git a/gdb/dwarf2-frame.c b/gdb/dwarf2-frame.c index 1ddf914a83c..6a40df5e325 100644 --- a/gdb/dwarf2-frame.c +++ b/gdb/dwarf2-frame.c @@ -491,15 +491,12 @@ dwarf2_frame_cache (struct frame_info *next_frame, void **this_cache) done for "normal" frames and not for resume-type frames (signal handlers, sentinel frames, dummy frames). - We don't do what GCC's does here (yet). It's not clear how - reliable the method is. There's also a problem with finding the - right FDE; see the comment in dwarf_frame_p. If dwarf_frame_p - selected this frame unwinder because it found the FDE for the - next function, using the adjusted return address might not yield - a FDE at all. The problem isn't specific to DWARF CFI; other - unwinders loose in similar ways. Therefore it's probably - acceptable to leave things slightly broken for now. */ - fs->pc = frame_pc_unwind (next_frame); + frame_unwind_address_in_block does just this. + + It's not clear how reliable the method is though - there is the + potential for the register state pre-call being different to that + on return. */ + fs->pc = frame_unwind_address_in_block (next_frame); /* Find the correct FDE. */ fde = dwarf2_frame_find_fde (&fs->pc); @@ -710,15 +707,11 @@ static const struct frame_unwind dwarf2_frame_unwind = const struct frame_unwind * dwarf2_frame_sniffer (struct frame_info *next_frame) { - CORE_ADDR pc = frame_pc_unwind (next_frame); - /* The way GDB works, this function can be called with PC just after - the last instruction of the function we're supposed to return the - unwind methods for. In that case we won't find the correct FDE; - instead we find the FDE for the next function, or we won't find - an FDE at all. There is a possible solution (see the comment in - dwarf2_frame_cache), GDB doesn't pass us enough information to - implement it. */ - if (dwarf2_frame_find_fde (&pc)) + /* Grab an address that is guarenteed to reside somewhere within the + function. frame_pc_unwind(), for a no-return next function, can + end up returning something past the end of this function's body. */ + CORE_ADDR block_addr = frame_unwind_address_in_block (next_frame); + if (dwarf2_frame_find_fde (&block_addr)) return &dwarf2_frame_unwind; return NULL; -- 2.30.2