; --------------------------------------------------------------------------------
; @Title: Script to investigate Segmentation Violations and other Faults on QNX
; @Description: 
;   See QNX Awareness Manual, chapter
;       "Debugging QNX"->"Trapping Segmentation Violation"
;   Call this script to set the appropriate breakpoints
;   and call it again to set the register set to the place
;   where the fault happened.
;   The registers are set temporarily; as soon as debugging
;   is continued (Step, Go, ...), the original registers
;   are restored.
; @Author: DIE
; @Copyright: (C) 1989-2022 Lauterbach GmbH, licensed for use with TRACE32(R) only
; --------------------------------------------------------------------------------
; $Id: segv.cmm 18850 2022-01-26 18:41:29Z bschroefel $


 LOCAL &usr_fault
 
 ; segmentation violation (usr_fault)
 IF sYmbol.EXIST(usr_fault)
   &usr_fault=ADDRESS.OFFSET(usr_fault)
 ELSE
 (
    PRINT "label ""usr_fault"" not found."
    ENDDO
 )
 Break.Set &usr_fault
 PRINT "breakpoint set on ""usr_fault""."
 
 ; if halted on segmentation violation (usr_fault)
 IF Register(pc)==&usr_fault
 (
    &code=Register(r0)
    &signo=&code&0xff
    &thread=Register(r1)
    &addr=Register(r2)
    &pc=Var.VALUE(((struct thread_entry)*&thread).reg.gpr[15])
    IF &signo==10.
      PRINT "bus error at address 0x" &addr ", PC = 0x" &pc
    ELSE IF &signo==11.
      PRINT "segmentation violation at address 0x" &addr ", PC = 0x" &pc
    ELSE
      PRINT "signo 0x" &signo " at address 0x" &addr ", PC = 0x" &pc
    GOSUB swap_registers &thread
    ENDDO
 )

 ENDDO


swap_registers:

 ; set register set temporarily to faulty state
 
 LOCAL &thread
 ENTRY &thread

 LOCAL &r0  &r1  &r2  &r3  &r4  &r5  &r6  &r7 
 LOCAL &r8  &r9  &r10 &r11 &r12 &r13 &r14 &r15
 LOCAL &spsr
 
 LOCAL &i

 ; first get all register values from thread context

 &i=0.
 WHILE &i<16.
 (
   ; collect all gpr registers to script variables &r0-&r15
   &ic=STRing.CUT("&i",-1)   ; to cut trailing dot
   &r&ic=Var.VALUE(((struct thread_entry)*&thread).reg.gpr[&ic]) ; &r0=v.v(.reg.gpr[0])
   &i=&i+1
 )
 &spsr=Var.VALUE(((struct thread_entry)*&thread).reg.spsr)

 ; second write values into registers temporarily

 &i=0.
 WHILE &i<16.
 (
   &ic=STRing.CUT("&i",-1)  ; to cut trailing dot
   &&value=&r&ic            ; && for recursive macro parsing
   Register.Set r&ic &value /Task Temporary  ; r.s r0 &r0
   &i=&i+1
 )
 Register.Set spsr &spsr /Task Temporary

 RETURN