Re: [PATCH v2 1/4] [SPARC] Errata workaround for GRLIB-TN-0012

[Eric Botcazou <ebotcazou@adacore.com>]

> 2017-11-17  Daniel Cederman  <cederman@gaisler.com>
> 
> 	* config/sparc/sparc.c (fpop_insn_p): New function.
> 	(sparc_do_work_around_errata): Insert NOP instructions to
> 	prevent sequences that could trigger the TN-0012 errata for
> 	GR712RC.
> 	(pass_work_around_errata::gate): Also test sparc_fix_gr712rc.
> 	* config/sparc/sparc.md (fix_gr712rc): New attribute.
> 	(in_branch_annul_delay): Prevent floating-point instructions
> 	in delay slot of annulled integer branch.

Sorry, I should have been more explicit in my first reply, because:

> @@ -590,6 +594,26 @@
>  	   (const_string "true")
>  	] (const_string "false")))
> 
> +(define_attr "in_integer_branch_annul_delay" "false,true"
> +  (cond [(eq_attr "type"
> "uncond_branch,branch,cbcond,uncond_cbcond,call,sibcall,call_no_delay_slot,
> multi") +	   (const_string "false")
> +	 (and (eq_attr "fix_gr712rc" "true")
> +	      (eq_attr "type" "fp,fpcmp,fpmove,fpcmove,fpmul,
> +			       fpdivs,fpsqrts,fpdivd,fpsqrtd"))
> +	   (const_string "false")
> +	 (and (eq_attr "fix_b2bst" "true") (eq_attr "type" "store,fpstore"))
> +	   (const_string "false")
> +	 (and (eq_attr "fix_ut699" "true") (eq_attr "type" "load,sload"))
> +	   (const_string "false")
> +	 (and (eq_attr "fix_ut699" "true")
> +	      (and (eq_attr "type" "fpload,fp,fpmove,fpmul,fpdivs,fpsqrts")
> +		   (ior (eq_attr "fptype" "single")
> +		        (eq_attr "fptype_ut699" "single"))))
> +	   (const_string "false")
> +	 (eq_attr "length" "1")
> +	   (const_string "true")
> +	] (const_string "false")))
> +
>  (define_delay (eq_attr "type" "call")
>    [(eq_attr "in_call_delay" "true") (nil) (nil)])

is barely maintainable.  So let's go back to the original version and...

> @@ -602,6 +626,10 @@
>  (define_delay (eq_attr "type" "branch")
>    [(eq_attr "in_branch_delay" "true") (nil) (eq_attr "in_branch_delay"
> "true")])
> 
> +(define_delay (and (eq_attr "type" "branch") (eq_attr "branch_type" "icc"))
> +  [(eq_attr "in_branch_delay" "true") (nil)
> +  (eq_attr "in_integer_branch_annul_delay" "true")])
> +
>  (define_delay (eq_attr "type" "uncond_branch")
>    [(eq_attr "in_branch_delay" "true") (nil) (nil)])

...add (and (.) (not (eq_attr "branch_type" "icc")) to the first define_delay.

-- 
Eric Botcazou