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Subject: Re: Hardware watchpoint for read
From: Philippe Waroquiers <philippe.waroquiers@skynet.be>
To: Xin Tong <xerox.time.tech@gmail.com>
Cc: "Gustavo, Luis" <luis_gustavo@mentor.com>, gdb@sourceware.org
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On Thu, 2012-05-03 at 15:41 -0400, Xin Tong wrote:
> The breakpoint instructions (int 3 on x86) are inserted in the
> translation process ?

Valgrind gdbserver implements breakpoints during code translation
by inserting calls to a Valgrind "helper" procedure.
You can use a Valgrind gdbserver monitor command to inspect
the translation:
  v.translate <addr> [<traceflags>]  : debug translation of <addr> with <traceflags>
    (default traceflags 0b00100000 : show after instrumentation)
   An additional flag  0b100000000 allows to show gdbserver instrumentation

read/write/access watchpoints are implemented on top of memcheck
"addressability" V bits. memcheck is the only Valgrind tool that
implements watchpoints.

Philippe