[Lazarus] Single-stepping assembler

[Mark Morgan Lloyd]

Mark Morgan Lloyd wrote:

> Both SPARC and ARM now expand \t in the assembler window. I've still got 
> a problem on ARM (i.e. Lazarus running on ARM, not a cross-compiler) 
> where trying to display the assembler window when at a breakpoint causes 
> the program to run, things are fine if the window is open before the 
> program is started.

More details as below. Starting with the assembler window not displayed, 
and running to a breakpoint in the source window:

   << TCmdLineDebugger.ReadLn "(gdb) "
   >> TCmdLineDebugger.SendCmdLn "-stack-list-frames 0 2"
   << TCmdLineDebugger.ReadLn 
"^done,stack=[frame={level="0",addr="0x00083be0",func="MOONPHASE_init",file="moonphase.pas",fullname="/usr/local/src/heavywethers/trunk/moonphase.pas",line="1002"},frame={level="1",addr="0x00037d90",fu" 
.(269).. 
"n",file="HeavyWethers.lpr",fullname="/usr/local/src/heavywethers/trunk/HeavyWethers.lpr",line="40"}]"
   << TCmdLineDebugger.ReadLn "(gdb) "
Exec done
Leaving Queue with count: 0 Recurse-Count=0 State=Pause
Executing (Recurse-Count=0) queued= 0 CmdPrior=1 CmdMinRunLvl=-1 : 
"TGDBMIDebuggerCommandLocals:" State=Pause PauseWaitState=0
   >> TCmdLineDebugger.SendCmdLn "-stack-list-arguments 1 0 0"
   << TCmdLineDebugger.ReadLn "^done,stack-args=[frame={level="0",args=[]}]"
   << TCmdLineDebugger.ReadLn "(gdb) "
   >> TCmdLineDebugger.SendCmdLn "-stack-list-locals 1"
   << TCmdLineDebugger.ReadLn "^done,locals=[]"
   << TCmdLineDebugger.ReadLn "(gdb) "
Exec done
Leaving Queue with count: 0 Recurse-Count=0 State=Pause

########### Now sitting on breakpoint in source window.
########### View -> Debug windows -> Assembler
########### Program runs without stopping.
########### At program's login dialogue tell it to abort.

INFO: TDBGDisassembler.FindRange: Address not found 539616 
wanted-before=5 wanted-after=22 in map with count=0
Executing (Recurse-Count=0) queued= 0 CmdPrior=30 CmdMinRunLvl=-1 : 
"TGDBMIDebuggerCommandDisassembe: FromAddr=539616 ToAddr=539616 
LinesBefore=5 LinesAfter=22" State=Pause PauseWaitState=0
   >> TCmdLineDebugger.SendCmdLn "-data-disassemble -s 539575 -e 539576 
-- 0"
   << TCmdLineDebugger.ReadLn ""
   [WARNING] TGDBMIDebugger:  ExecuteCommand "-data-disassemble -s 
539575 -e 539576 -- 0" failed.
   INFO: TDBGDisassembler.Clear:  map had count=0
   Canceling: "TGDBMIDebuggerCommandDisassembe: FromAddr=539616 
ToAddr=539616 LinesBefore=5 LinesAfter=22"

(lazarus:1183): Gtk-CRITICAL **: gtk_text_view_scroll_to_iter: assertion 
`yalign >= 0.0 && yalign <= 1.0' failed

########### Now have IDE "Debugger error ...
########### The GDB process is no longer running" box.
###########
########### The GDB command:
########### "-data-disassemble -s 539575 -e 539576 -- 0"
########### did not return any result.

r32281 2.4.4 gdb 7.0.1-debian

Restarting IDE, displaying assembler window and running to breakpoint 
(marked below with > at start of line):

   moonphase.pas:1001                Assert(test_jDayToSecs);
   00083BB4 84fcffeb                 bl              0x82dcc 
<TEST_JDAYTOSECS>
   00083BB8 000050e3                 cmp             r0, #0
   00083BBC 0700001a                 bne             0x83be0 
<MOONPHASE_init+332>
   00083BC0 0b30a0e1                 mov             r3, r11
   00083BC4 032ca0e3                 mov             r2, #768        ; 0x300
   00083BC8 e92082e3                 orr             r2, r2, #233    ; 0xe9
   00083BCC f8009fe5                 ldr             r0, [pc, #248]  ; 
0x83ccc <MOONPHASE_init+568>
   00083BD0 0010a0e1                 mov             r1, r0
   00083BD4 f4409fe5                 ldr             r4, [pc, #244]  ; 
0x83cd0 <MOONPHASE_init+572>
   00083BD8 0400a0e1                 mov             r0, r4
   00083BDC acd2feeb                 bl              0x38694 <fpc_assert>
   moonphase.pas:1002                Assert(test_jYear);
 > 00083BE0 b1fcffeb                 bl              0x82eac <TEST_JYEAR>
   00083BE4 000050e3                 cmp             r0, #0
   00083BE8 0700001a                 bne             0x83c0c 
<MOONPHASE_init+376>
   00083BEC 0b30a0e1                 mov             r3, r11
   00083BF0 032ca0e3                 mov             r2, #768        ; 0x300
   00083BF4 ea2082e3                 orr             r2, r2, #234    ; 0xea
   00083BF8 cc009fe5                 ldr             r0, [pc, #204]  ; 
0x83ccc <MOONPHASE_init+568>
   00083BFC 0010a0e1                 mov             r1, r0
   00083C00 c8409fe5                 ldr             r4, [pc, #200]  ; 
0x83cd0 <MOONPHASE_init+572>
   00083C04 0400a0e1                 mov             r0, r4
   00083C08 a1d2feeb                 bl              0x38694 <fpc_assert>
   moonphase.pas:1008                Assert(test_Phase);

I've saved that file in case you want a copy by e.g. direct mail.

-- 
Mark Morgan Lloyd
markMLl .AT. telemetry.co .DOT. uk

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