Re: [PATCH] Set discriminators for call stmts on the same line within the same basic block

[Jason Merrill <jason@redhat.com>]

On 10/6/22 23:50, Eugene Rozenfeld wrote:
> Thank you for the review Jason.
> 
> I fixed formatting and updated the commit description:

OK.

> ----------------------------
> 
> Call statements are possible split points of a basic block so they may end up
> in different basic blocks by the time pass_ipa_auto_profile executes.
> 
> This change will also simplify call site lookups since now location with discriminator
> will uniquely identify the call site (no callee function name is needed).
> 
> This change is based on commit 1e6c4a7a8fb8e20545bb9f9032d3854f3f794c18
> by Dehao Chen in vendors/google/heads/gcc-4_8.
> 
> Tested on x86_64-pc-linux-gnu.
> 
> gcc/ChangeLog:
> 	* tree-cfg.cc (assign_discriminators): Set discriminators for call stmts
> 	on the same line within the same basic block.
> ---
>   gcc/tree-cfg.cc | 32 ++++++++++++++++++++++++++++++++
>   1 file changed, 32 insertions(+)
> 
> diff --git a/gcc/tree-cfg.cc b/gcc/tree-cfg.cc
> index ade66c54499..f6a465f4c91 100644
> --- a/gcc/tree-cfg.cc
> +++ b/gcc/tree-cfg.cc
> @@ -1203,8 +1203,40 @@ assign_discriminators (void)
>       {
>         edge e;
>         edge_iterator ei;
> +      gimple_stmt_iterator gsi;
>         gimple *last = last_stmt (bb);
>         location_t locus = last ? gimple_location (last) : UNKNOWN_LOCATION;
> +      location_t curr_locus = UNKNOWN_LOCATION;
> +      int curr_discr = 0;
> +
> +      /* Traverse the basic block, if two function calls within a basic block
> +	are mapped to the same line, assign a new discriminator because a call
> +	stmt could be a split point of a basic block.  */
> +      for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
> +	{
> +	  gimple *stmt = gsi_stmt (gsi);
> +	  expanded_location curr_locus_e;
> +	  if (curr_locus == UNKNOWN_LOCATION)
> +	    {
> +	      curr_locus = gimple_location (stmt);
> +	      curr_locus_e = expand_location (curr_locus);
> +	    }
> +	  else if (!same_line_p (curr_locus, &curr_locus_e, gimple_location (stmt)))
> +	    {
> +	      curr_locus = gimple_location (stmt);
> +	      curr_locus_e = expand_location (curr_locus);
> +	      curr_discr = 0;
> +	    }
> +	  else if (curr_discr != 0)
> +	    {
> +	      location_t loc = gimple_location (stmt);
> +	      location_t dloc = location_with_discriminator (loc, curr_discr);
> +	      gimple_set_location (stmt, dloc);
> +	    }
> +	  /* Allocate a new discriminator for CALL stmt.  */
> +	  if (gimple_code (stmt) == GIMPLE_CALL)
> +	    curr_discr = next_discriminator_for_locus (curr_locus);
> +	}
>   
>         if (locus == UNKNOWN_LOCATION)
>   	continue;