[Bug tree-optimization/18441] New: Vectorizer: add a command line for simple vectorizer report

[Bug tree-optimization/18441] New: Vectorizer: add a command line for simple vectorizer report

[giovannibajo at libero dot it]

If an user wants to know if vectorization succeeded or not, he has to use -
fdump-tree-vect-details and then grep for some special pattern to find the 
lines that say if loops were vectorized or not.

Such an information can be very useful while developing code, so I think it 
should be easily given. ICC has an option /Qvec_report[=n] to setup a 
diagnostic (equivalent to our inform()), with different verbosity levels. I 
suggest we add something like this to GCC as well.


/Qvec_report[n]  control amount of vectorizer diagnostic information:
            n=0    no diagnostic information
            n=1    indicate vectorized loops (DEFAULT)
            n=2    indicate vectorized/non-vectorized loops
            n=3    indicate vectorized/non-vectorized loops and prohibiting
                   data dependence information
            n=4    indicate non-vectorized loops
            n=5    indicate non-vectorized loops and prohibiting data
                   dependence information


With such an infrastructure, we could also change the vectorizer testsuite not 
to scan the details dump and just do a { dg-inform "VECTORIZED" } (or similar) 
on the line with the loop header.

-- 
           Summary: Vectorizer: add a command line for simple vectorizer
                    report
           Product: gcc
           Version: 4.0.0
            Status: UNCONFIRMED
          Severity: enhancement
          Priority: P2
         Component: tree-optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: giovannibajo at libero dot it
                CC: gcc-bugs at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18441

[Bug tree-optimization/18441] Vectorizer: add a command line for simple vectorizer report

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-11-12 02:45 -------
Confirmed, We should have done this by now but don't for reasons unknown to me.  We have all the 
information we need as of right now.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |pinskia at gcc dot gnu dot
                   |                            |org
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|                            |1
           Keywords|                            |diagnostic
   Last reconfirmed|0000-00-00 00:00:00         |2004-11-12 02:45:12
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18441

[Bug tree-optimization/18441] Vectorizer: add a command line for simple vectorizer report

[dpatel at apple dot com]

------- Additional Comments From dpatel at apple dot com  2004-12-13 20:16 -------
Try -fdump-tree-vect-stats. It produces more user friendly output compared to -details.

I am not fan of putting such diagnostics as part of warnings/info/errors.   IMO, we should enhance/
update -fdump-tree-vect-stats to meet user's requirements.

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18441

[Bug tree-optimization/18441] Vectorizer: add a command line for simple vectorizer report

[leehod at il dot ibm dot com]

------- Additional Comments From leehod at il dot ibm dot com  2004-12-22 18:59 -------
I am working with Dorit on cleaning up the vectorizer dumps. We'd also like to 
try to address this PR - here are some preliminary thoughts/questions:

1) The 'inform' utility doesn't look very suitable because it prints the line 
information of the function and we want the line info of the loop, so a typical 
printout would look like this:
loop at trees.c:499: Success! loop vectorized.
Also, it only prints to stderr, and we want to be able to print the same 
information also to a dump-file. Maybe we want a 'vect_inform' that (1) would 
not print the function line-number but some other line-number passed as 
argument (the loop line-number), and (2) could be made to print either to 
stderr or to a dump-file?

2) How about using a mechanism like -fsched-verbose? If -ftree-vect-verbose=x 
is used and a dump-file is available, then the output will be printed into the 
dump-file; otherwise, it will be printed into stderr. If -ftree-vect-verbose=x 
is used then there will be no difference between -fdump-tree-vect-details and -
fdump-tree-vect-stats (they will both use the same verbosity level x).  If -
ftree-vect-verbose is not specified, then -fdump-tree-vect-details could use 
the highest verbosity level as default, and -fdump-tree-vect-stats could use 
the lowest verbosity level.

3) We could use the different verbosity levels to prune the number of non-
vectorized-loops we report about, not just the amount of detail we report. For 
example:
level 0: no diagnostic information.
level 1: report vectorized loops only
level 2: report vectorized loops and non-vectorized inner-most loops that 
passed the first analysis phase (vect_analyze_loop_form).
level 3: report vectorized loops and non-vectorized inner-most loops
level 4: report vectorized loops and all non-vectorized loops
level 5: full debug information (vectorized/non-vectorized loops, data-
dependence/scalar-evolution dumps)

4) Is there a mechanism in the testsuite to analyze output to stderr?

thanks,
Leehod


-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |dorit at il dot ibm dot com,
                   |                            |leehod at il dot ibm dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18441

[Bug tree-optimization/18441] Vectorizer: add a command line for simple vectorizer report

[leehod at il dot ibm dot com]

------- Additional Comments From leehod at il dot ibm dot com  2005-01-19 19:28 -------
There is now a patch addressing these issues. 
See: http://gcc.gnu.org/ml/gcc-patches/2005-01/msg01247.html


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18441

[Bug tree-optimization/18441] Vectorizer: add a command line for simple vectorizer report

[dorit at il dot ibm dot com]

------- Additional Comments From dorit at il dot ibm dot com  2005-02-09 19:30 -------
continued in this thread:
http://gcc.gnu.org/ml/gcc-patches/2005-02/msg00196.html

and cmmitted:
http://gcc.gnu.org/ml/gcc-cvs/2005-02/msg00153.html

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18441

[Bug tree-optimization/18441] Vectorizer: add a command line for simple vectorizer report

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2005-05-21 12:51 -------
Fixed for 4.0.0.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |FIXED
   Target Milestone|---                         |4.0.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18441