From b05f243280c921455098656b2fdafecdd58f9cb4 Mon Sep 17 00:00:00 2001 From: Mark Kettenis Date: Wed, 28 Mar 2001 11:36:23 +0000 Subject: [PATCH] * i386-linux-tdep.c (FRAMELESS_SIGNAL): Moved here from config/i386/nm-linux.h (including comment). (i386_linux_frame_chain): New function implementing guts of the former FRAME_CHAIN macro, but using read_memory_unsigned_integer instead of read_memory_integer. (i386_linux_frame_saved_pc): Removed doc pointing to i386/tm-linux.h for an explanation of FRAMELESS_SIGNAL since that now lives in this file. * config/i386/tm-linux.h (FRAMELESS_SIGNAL): Moved to i386-linux-tdep.c (including comment). (FRAME_CHAIN): Redefined in terms of i386_linux_frame_chain. (i386_linux_frame_chain): New prototype. --- gdb/ChangeLog | 13 +++++++++++ gdb/config/i386/tm-linux.h | 36 ++----------------------------- gdb/i386-linux-tdep.c | 44 ++++++++++++++++++++++++++++++++------ 3 files changed, 53 insertions(+), 40 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 99dc2be219c..bfd75947368 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,5 +1,18 @@ 2001-03-28 Mark Kettenis + * i386-linux-tdep.c (FRAMELESS_SIGNAL): Moved here from + config/i386/nm-linux.h (including comment). + (i386_linux_frame_chain): New function implementing guts of the + former FRAME_CHAIN macro, but using read_memory_unsigned_integer + instead of read_memory_integer. + (i386_linux_frame_saved_pc): Removed doc pointing to + i386/tm-linux.h for an explanation of FRAMELESS_SIGNAL since that + now lives in this file. + * config/i386/tm-linux.h (FRAMELESS_SIGNAL): Moved to + i386-linux-tdep.c (including comment). + (FRAME_CHAIN): Redefined in terms of i386_linux_frame_chain. + (i386_linux_frame_chain): New prototype. + * gdbserver/low-linux.c [I386_GNULINUX_TARGET]: Cleanup code and make it work again. (NUM_FREGS): Redefine to 0. diff --git a/gdb/config/i386/tm-linux.h b/gdb/config/i386/tm-linux.h index 6c34498cbf1..acfecf58341 100644 --- a/gdb/config/i386/tm-linux.h +++ b/gdb/config/i386/tm-linux.h @@ -46,41 +46,9 @@ extern struct link_map_offsets *i386_linux_svr4_fetch_link_map_offsets (void); #define IN_SIGTRAMP(pc, name) i386_linux_in_sigtramp (pc, name) extern int i386_linux_in_sigtramp (CORE_ADDR, char *); -/* Signal trampolines don't have a meaningful frame. As in tm-i386.h, - the frame pointer value we use is actually the frame pointer of the - calling frame--that is, the frame which was in progress when the - signal trampoline was entered. gdb mostly treats this frame - pointer value as a magic cookie. We detect the case of a signal - trampoline by looking at the SIGNAL_HANDLER_CALLER field, which is - set based on IN_SIGTRAMP. - - When a signal trampoline is invoked from a frameless function, we - essentially have two frameless functions in a row. In this case, - we use the same magic cookie for three frames in a row. We detect - this case by seeing whether the next frame has - SIGNAL_HANDLER_CALLER set, and, if it does, checking whether the - current frame is actually frameless. In this case, we need to get - the PC by looking at the SP register value stored in the signal - context. - - This should work in most cases except in horrible situations where - a signal occurs just as we enter a function but before the frame - has been set up. */ - -#define FRAMELESS_SIGNAL(FRAME) \ - ((FRAME)->next != NULL \ - && (FRAME)->next->signal_handler_caller \ - && frameless_look_for_prologue (FRAME)) - #undef FRAME_CHAIN -#define FRAME_CHAIN(FRAME) \ - ((FRAME)->signal_handler_caller \ - ? (FRAME)->frame \ - : (FRAMELESS_SIGNAL (FRAME) \ - ? (FRAME)->frame \ - : (!inside_entry_file ((FRAME)->pc) \ - ? read_memory_integer ((FRAME)->frame, 4) \ - : 0))) +#define FRAME_CHAIN(frame) i386_linux_frame_chain (frame) +extern CORE_ADDR i386_linux_frame_chain (struct frame_info *frame); #undef FRAME_SAVED_PC #define FRAME_SAVED_PC(frame) i386_linux_frame_saved_pc (frame) diff --git a/gdb/i386-linux-tdep.c b/gdb/i386-linux-tdep.c index 56a5eadecd9..f98801b4d0c 100644 --- a/gdb/i386-linux-tdep.c +++ b/gdb/i386-linux-tdep.c @@ -277,6 +277,44 @@ i386_linux_sigtramp_saved_sp (struct frame_info *frame) return read_memory_integer (addr + LINUX_SIGCONTEXT_SP_OFFSET, 4); } +/* Signal trampolines don't have a meaningful frame. As in + "i386/tm-i386.h", the frame pointer value we use is actually the + frame pointer of the calling frame -- that is, the frame which was + in progress when the signal trampoline was entered. GDB mostly + treats this frame pointer value as a magic cookie. We detect the + case of a signal trampoline by looking at the SIGNAL_HANDLER_CALLER + field, which is set based on IN_SIGTRAMP. + + When a signal trampoline is invoked from a frameless function, we + essentially have two frameless functions in a row. In this case, + we use the same magic cookie for three frames in a row. We detect + this case by seeing whether the next frame has + SIGNAL_HANDLER_CALLER set, and, if it does, checking whether the + current frame is actually frameless. In this case, we need to get + the PC by looking at the SP register value stored in the signal + context. + + This should work in most cases except in horrible situations where + a signal occurs just as we enter a function but before the frame + has been set up. */ + +#define FRAMELESS_SIGNAL(frame) \ + ((frame)->next != NULL \ + && (frame)->next->signal_handler_caller \ + && frameless_look_for_prologue (frame)) + +CORE_ADDR +i386_linux_frame_chain (struct frame_info *frame) +{ + if (frame->signal_handler_caller || FRAMELESS_SIGNAL (frame)) + return frame->frame; + + if (! inside_entry_file (frame->pc)) + return read_memory_unsigned_integer (frame->frame, 4); + + return 0; +} + /* Return the saved program counter for FRAME. */ CORE_ADDR @@ -285,11 +323,6 @@ i386_linux_frame_saved_pc (struct frame_info *frame) if (frame->signal_handler_caller) return i386_linux_sigtramp_saved_pc (frame); - /* See comment in "i386/tm-linux.h" for an explanation what this - "FRAMELESS_SIGNAL" stuff is supposed to do. - - FIXME: kettenis/2001-03-26: That comment should eventually be - moved to this file. */ if (FRAMELESS_SIGNAL (frame)) { CORE_ADDR sp = i386_linux_sigtramp_saved_sp (frame->next); @@ -309,7 +342,6 @@ i386_linux_saved_pc_after_call (struct frame_info *frame) return read_memory_integer (read_register (SP_REGNUM), 4); } - /* Calling functions in shared libraries. */ -- 2.30.2