Re: [PATCH 2/3] Add a pass to automatically add ptwrite instrumentation

On Tue, Nov 13, 2018 at 07:37:27PM +0100, Richard Biener wrote: > I'd look at doing the instrumentation after var-tracking has run - that is > what computes the locations in the end. That means instrumenting on late RTL > after register allocation (and eventually with branch range restrictions

Re: [PATCH 2/3] Add a pass to automatically add ptwrite instrumentation

On November 13, 2018 7:09:15 PM GMT+01:00, Andi Kleen wrote: >On Tue, Nov 13, 2018 at 09:03:52AM +0100, Richard Biener wrote: >> > I even had an earlier version of this that instrumented >> > assembler output of the compiler with PTWRITE in a separate script, >> > and it worked fine too. >> >>

Re: [PATCH 2/3] Add a pass to automatically add ptwrite instrumentation

On Tue, Nov 13, 2018 at 09:03:52AM +0100, Richard Biener wrote: > > I even had an earlier version of this that instrumented > > assembler output of the compiler with PTWRITE in a separate script, > > and it worked fine too. > > Apart from eventually messing up branch range restrictions I guess ;)

Re: [PATCH 2/3] Add a pass to automatically add ptwrite instrumentation

On Mon, Nov 12, 2018 at 4:16 AM Andi Kleen wrote: > > On Sun, Nov 11, 2018 at 10:06:21AM +0100, Richard Biener wrote: > > That is, usually debuggers look for a location list of a variable > > and find, say, %rax. But for ptwrite the debugger needs to > > examine all active location lists for,

Re: [PATCH 2/3] Add a pass to automatically add ptwrite instrumentation

On Sun, Nov 11, 2018 at 10:06:21AM +0100, Richard Biener wrote: > That is, usually debuggers look for a location list of a variable > and find, say, %rax. But for ptwrite the debugger needs to > examine all active location lists for, say, %rax and figure out > that it contains the value for

Re: [PATCH 2/3] Add a pass to automatically add ptwrite instrumentation

On Sun, Nov 11, 2018 at 11:37:57AM -0700, Martin Sebor wrote: > One other high-level comment: a more powerful interface to > variable tracing than annotating declarations in the source > would be to provide either the names of the symbols to trace > on the command line or in an external file.

Re: [PATCH 2/3] Add a pass to automatically add ptwrite instrumentation

One other high-level comment: a more powerful interface to variable tracing than annotating declarations in the source would be to provide either the names of the symbols to trace on the command line or in an external file. That way tracing could be enabled for objects and types declared in

Re: [PATCH 2/3] Add a pass to automatically add ptwrite instrumentation

On Fri, Nov 9, 2018 at 7:18 PM Andi Kleen wrote: > > Hi Richard, > > On Fri, Nov 09, 2018 at 04:27:22PM +0100, Richard Biener wrote: > > > Passes bootstrap and test suite on x86_64-linux, also > > > bootstrapped and tested gcc itself with full -fvartrace > > > and -fvartrace-locals

Re: [PATCH 2/3] Add a pass to automatically add ptwrite instrumentation

On 11/04/2018 12:32 AM, Andi Kleen wrote: From: Andi Kleen Add a new pass to automatically instrument changes to variables with the new PTWRITE instruction on x86. PTWRITE writes a 4 or 8 byte field into an Processor Trace log, which allows log over head logging of informatin. This allows to

Re: [PATCH 2/3] Add a pass to automatically add ptwrite instrumentation

Hi Richard, On Fri, Nov 09, 2018 at 04:27:22PM +0100, Richard Biener wrote: > > Passes bootstrap and test suite on x86_64-linux, also > > bootstrapped and tested gcc itself with full -fvartrace > > and -fvartrace-locals instrumentation. > > So how is this supposed to be used? I guess in a >

Re: [PATCH 2/3] Add a pass to automatically add ptwrite instrumentation

On Sun, Nov 4, 2018 at 7:33 AM Andi Kleen wrote: > > From: Andi Kleen > > Add a new pass to automatically instrument changes to variables > with the new PTWRITE instruction on x86. PTWRITE writes a 4 or 8 byte > field into an Processor Trace log, which allows log over head > logging of

[PATCH 2/3] Add a pass to automatically add ptwrite instrumentation

From: Andi Kleen Add a new pass to automatically instrument changes to variables with the new PTWRITE instruction on x86. PTWRITE writes a 4 or 8 byte field into an Processor Trace log, which allows log over head logging of informatin. This allows to reconstruct how values later, which can be

[PATCH 2/3] Add a pass to automatically add ptwrite instrumentation

From: Andi Kleen Add a new pass to automatically instrument changes to variables with the new PTWRITE instruction on x86. PTWRITE writes a 4 or 8 byte field into an external Processor Trace log. This allows to reconstruct how values later, which can be useful for debugging