From 7b98a091361fd9660ed38f0e196a605bf324e160 Mon Sep 17 00:00:00 2001 From: Peter Schauer Date: Tue, 17 Aug 1993 08:49:07 +0000 Subject: [PATCH] * config/i386/tm-i386bsd.h (SIGTRAMP_START, SIGTRAMP_END, FRAME_CHAIN, FRAMELESS_FUNCTION_INVOCATION, FRAME_SAVED_PC, SIGCONTEXT_PC_OFFSET): Define to make backtracing through sigtramp work. * config/vax/tm-vax.h (SIGTRAMP_START, SIGTRAMP_END, TARGET_UPAGES, FRAME_SAVED_PC, SIGCONTEXT_PC_OFFSET): Ditto. --- gdb/config/i386/tm-i386bsd.h | 47 ++++++++++++++++++++++++++++++++++++ gdb/config/vax/tm-vax.h | 36 +++++++++------------------ 2 files changed, 59 insertions(+), 24 deletions(-) diff --git a/gdb/config/i386/tm-i386bsd.h b/gdb/config/i386/tm-i386bsd.h index 6f4dbd939ae..f75fd93ae6e 100644 --- a/gdb/config/i386/tm-i386bsd.h +++ b/gdb/config/i386/tm-i386bsd.h @@ -27,3 +27,50 @@ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ /* BSDI can't handle them either. */ #undef NUM_REGS #define NUM_REGS 10 + +/* On 386 bsd, sigtramp is above the user stack and immediately below + the user area. Using constants here allows for cross debugging. + These are tested for BSDI but should work on 386BSD. */ +#define SIGTRAMP_START 0xfdbfdfc0 +#define SIGTRAMP_END 0xfdbfe000 + +/* The following redefines make backtracing through sigtramp work. + They manufacture a fake sigtramp frame and obtain the saved pc in sigtramp + from the sigcontext structure which is pushed by the kernel on the + user stack, along with a pointer to it. */ + +/* FRAME_CHAIN takes a frame's nominal address and produces the frame's + chain-pointer. + In the case of the i386, the frame's nominal address + is the address of a 4-byte word containing the calling frame's address. */ +#undef FRAME_CHAIN +#define FRAME_CHAIN(thisframe) \ + (thisframe->signal_handler_caller \ + ? thisframe->frame \ + : (!inside_entry_file ((thisframe)->pc) \ + ? read_memory_integer ((thisframe)->frame, 4) \ + : 0)) + +/* A macro that tells us whether the function invocation represented + by FI does not have a frame on the stack associated with it. If it + does not, FRAMELESS is set to 1, else 0. */ +#undef FRAMELESS_FUNCTION_INVOCATION +#define FRAMELESS_FUNCTION_INVOCATION(FI, FRAMELESS) \ + do { \ + if ((FI)->signal_handler_caller) \ + (FRAMELESS) = 0; \ + else \ + (FRAMELESS) = frameless_look_for_prologue(FI); \ + } while (0) + +/* Saved Pc. Get it from sigcontext if within sigtramp. */ + +/* Offset to saved PC in sigcontext, from . */ +#define SIGCONTEXT_PC_OFFSET 20 + +#undef FRAME_SAVED_PC(FRAME) +#define FRAME_SAVED_PC(FRAME) \ + (((FRAME)->signal_handler_caller \ + ? sigtramp_saved_pc (FRAME) \ + : read_memory_integer ((FRAME)->frame + 4, 4)) \ + ) diff --git a/gdb/config/vax/tm-vax.h b/gdb/config/vax/tm-vax.h index 6fd245412ef..856b889a45f 100644 --- a/gdb/config/vax/tm-vax.h +++ b/gdb/config/vax/tm-vax.h @@ -17,26 +17,6 @@ You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ -/* There is one known bug with VAX support that I don't know how to - fix: if you do a backtrace from a signal handler, you get something - like: -#0 0xbc in kill (592, 3) -#1 0x7f in hand (...) (...) -#2 0x7fffec7e in ?? (2, 0, 2147478112, 94) - ^^ GDB doesn't know about sigtramp -#3 0x7fffec70 in ?? (592, 2) - ^^^^^^^^^^ wrong address -#4 0xae in main (...) (...) - -when the correct backtrace (as given by adb) is: -_kill(250,3) from _hand+21 -_hand(2,0,7fffea60,5e) from 7fffec7e -sigtramp(2,0,7fffea60,5e) from _kill+4 -_kill(250,2) from _main+2e -_main(1,7fffeac4,7fffeacc) from start+3d - -If anyone knows enough about VAX BSD to fix this, please send the -fix to bug-gdb@prep.ai.mit.edu. */ #define TARGET_BYTE_ORDER LITTLE_ENDIAN @@ -76,14 +56,15 @@ fix to bug-gdb@prep.ai.mit.edu. */ #define SAVED_PC_AFTER_CALL(frame) FRAME_SAVED_PC(frame) -#define TARGET_UPAGES 10 +#define TARGET_UPAGES 14 #define TARGET_NBPG 512 #define STACK_END_ADDR (0x80000000 - (TARGET_UPAGES * TARGET_NBPG)) /* On the VAX, sigtramp is in the u area. Can't check the exact addresses because for cross-debugging we don't have VAX include files around. This should be close enough. */ -#define IN_SIGTRAMP(pc, name) ((pc) >= STACK_END_ADDR && (pc < 0x80000000)) +#define SIGTRAMP_START STACK_END_ADDR +#define SIGTRAMP_END 0x80000000 /* Stack grows downward. */ @@ -231,9 +212,16 @@ fix to bug-gdb@prep.ai.mit.edu. */ /* On the vax, all functions have frames. */ #define FRAMELESS_FUNCTION_INVOCATION(FI, FRAMELESS) {(FRAMELESS) = 0;} -/* Saved Pc. */ +/* Saved Pc. Get it from sigcontext if within sigtramp. */ -#define FRAME_SAVED_PC(FRAME) (read_memory_integer ((FRAME)->frame + 16, 4)) +/* Offset to saved PC in sigcontext, from . */ +#define SIGCONTEXT_PC_OFFSET 12 + +#define FRAME_SAVED_PC(FRAME) \ + (((FRAME)->signal_handler_caller \ + ? sigtramp_saved_pc (FRAME) \ + : read_memory_integer ((FRAME)->frame + 16, 4)) \ + ) /* Cannot find the AP register value directly from the FP value. Must find it saved in the frame called by this one, or in the AP -- 2.30.2