Hello everyone,
I started implementing BBL execution hooking. Requirements were that two
callbacks (bbl_start and bbl_stop) are called when a BBL is executed.
Since bbl_start is called through a gen_helper in
gen_intermediate_code_internal, that is not a problem.
But I saw that modifying gen_eob() so that gen_helper_bbl_stop() is
called does not trigger all ends of a BBL.
Some sample output:
BBL start at 0x1002a12
BBL stop with 5 instructions
BBL start at 0x1002a1b
BBL start at 0x10029b3
BBL start at 0x10029cc
BBL start at 0x10029e4
BBL stop with 4 instructions
here you see that on the first and the last BBL the stop callback is
called properly but not for the other three.
Disassembly:
1002a1b: 85 c0 test %eax,%eax
1002a1d: 75 94 jne 0x10029b3
10029b3: 83 7d e4 50 cmpl $0x50,-0x1c(%ebp)
10029b7: 75 13 jne 0x10029cc
10029cc: a1 3c 98 00 01 mov 0x100983c,%eax
10029d1: 3b c6 cmp %esi,%eax
10029d3: 74 0f je 0x10029e4
The two working BBLs end up in a call instruction. Is gen_eob() not used
on conditional jump instructions? Since I were not able to find how you
handle je/jne my question is where you handle that.
Regards,
Felix
