Dear all,
As I continue to work on this I have found something that is surprising.
I wrote this code :
int foo (int argc, int argv)
{
bar (argv, argc);
return 0;
}
On my architecture, this is transformed into the following assembly code:
mov r6 = InputReg1
mov InputReg1 = InputReg2
mov InputReg2 = tmp
However, I am of course looking at the debug information, and I was
surprised to see that :
<2><12f>: Abbrev Number: 6 (DW_TAG_formal_parameter)
<130> DW_AT_name : argc
<135> DW_AT_decl_file : 1
<136> DW_AT_decl_line : 4
<137> DW_AT_type : <af>
<13b> DW_AT_location : 0x38 (location list)
<2><13f>: Abbrev Number: 6 (DW_TAG_formal_parameter)
<140> DW_AT_name : argv
<145> DW_AT_decl_file : 1
<146> DW_AT_decl_line : 4
<147> DW_AT_type : <af>
<14b> DW_AT_location : 0x6e (location list)
This is ok, no problems here. But if I look at the locations given for
these variables:
00000038 00000000 0000000c (DW_OP_InputReg1)
00000038 0000000c 0000001c (DW_OP_r6)
00000038 <End of list>
0000006e 00000000 00000010 (DW_OP_InputReg2)
0000006e <End of list>
Is there any reason why the compiler does not generate the debug
information showing that the InputReg1 is now in InputReg2 and
vice-versa? It would seem to me that the debugger would need this
information but I may be mistaken.
As always, thanks for your input,
Jc
