On Tue, Dec 4, 2012 at 12:47 PM, Steven Bosscher <stevenb....@gmail.com> wrote:
> On Tue, Dec 4, 2012 at 9:14 PM, Xinliang David Li wrote:
>> I assume the graph dump does not support multiple function dump (I
>> noticed that the previous function's dump gets overwritten). This
>> reminds me that I need to resurrect my per-function dump support, and
>> dump-before/after patches at some point.
>
> Not sure what you mean with "multiple function dump"...?
>
> What my dumper does, is dump each function as a subgraph. If you dump
> a translation unit with more than one function, all function graphs
> will be in the same file. With a good DOT viewer, it's still quite
> readable.
Was it a bug then?
for this program:
typedef unsigned int uint;
int foo (uint a, uint b, uint c, uint d, uint e, uint f)
{
return (a*b + (c << 1) + (d << e) + f + 1);
}
int foo2 (uint a, uint b, uint c, uint d, uint e, uint f)
{
return ((f<<e) + (d << 1) + (c*b) + a + 1);
}
The dot file generated with -fdump-tree-optimized-graph is
digraph "" {
overlap=false;
subgraph "foo2" {
color="black";
label="foo2";
fn_1_basic_block_1 [shape=Mdiamond,style=filled,fillcolor=white,label="EXIT"];
fn_1_basic_block_2
[shape=record,style=filled,fillcolor=lightgrey,label="{\<bb\ 2\>:\l\
|e.1_2\ =\ (int)\ e_1(D);\l\
|_4\ =\ f_3(D)\ \<\<\ e.1_2;\l\
|_6\ =\ d_5(D)\ \<\<\ 1;\l\
|_10\ =\ c_8(D)\ *\ b_9(D);\l\
|_7\ =\ a_12(D)\ +\ 1;\l\
|_11\ =\ _7\ +\ _10;\l\
|_13\ =\ _11\ +\ _6;\l\
|_14\ =\ _13\ +\ _4;\l\
|_15\ =\ (int)\ _14;\l\
|return\ _15;\l\
}"];
fn_1_basic_block_0 [shape=Mdiamond,style=filled,fillcolor=white,label="ENTRY"];
fn_1_basic_block_0:s -> fn_1_basic_block_2:n
[style="solid,bold",color=blue,weight=100,constraint=true];
fn_1_basic_block_2:s -> fn_1_basic_block_1:n
[style="solid,bold",color=black,weight=10,constraint=true];
}
}
There is no subgraph -- did I miss anything?
>
> I have a perl scriptlet in the pipe line to split one DOT file into
> per-function DOT files, and to merge per-function DOT files from
> different passes.
It will be nicer to avoid any postprocessing. Once we have the ability
to dump one function at a time, the support will be there
automatically.
>
>
>> Why can't the dot dumper dump the count/frequency/branch prob
>> information? The attached dot file is generated from an assembly file
>> dumped with -S -dA option.
>
> It can, and should. I just didn't get around to that yet.
ok.
>
> I want to add the count//freq/branchprob as edge labels, similar to
> your dump. I also want to add it to the basic blocks as well but I'm
> not sure how to pretty-print it such that it doesn't clobber the view
> of the instructions contained in the basic block. Unfortunately DOT
> doesn't support edge classes or layers you can toggle.
>
> I even had the dumper print the GIMPLE SSA web and DF DU/UD chains,
> using ports on the fields in the record nodes that I use for dumping
> the instructions. But that really cluttered the graph too much. I'm
> still going to add the ports, at least, to use in dumping the
> scheduler's dependence graph.
DU/UD chains are good source of information -- the problem is it can
be too dense. Conceivably, this can be dumped on-demand for selected
webs.
>
> The whole graph dumping infrastructure will get another overhaul for
> GCC 4.9 to make it easier to use for non-CFG dumps and to allow passes
> to add their own meta-data to the dumps.
Do you have a brief design somewhere?
thanks,
David
>
> Ciao!
> Steven
