[testsuite/guality] Use line number vars in gdb-test

Hi,

I played around with pr45882.c and ran into FAILs.  It took me a while to
realize that the FAILs where due to the gdb-test (a dg-final action) using
absolute line numbers, and me adding lines before the gdb-test lines.

I've written this patch, which factors out the handling of relative line
numbers as well as line number variables from process-message, and reuses the
functionality in gdb-test.

This enables the line number variables functionality in gdb-test.  [ There's
one quirk: line number variables have a define-before-use semantics (with
matching used-before-defined error) but in the test-case the use in gdb-test
preceeds the definition in gdb-line.  This doesn't cause errors, because
the dg-final actions are executed after the definition has taken effect. ]

[ Relative line numbers still don't work in gdb-test, but that's due to an
orthogonal issue: gdb-test is a dg-final action, and while dg-final receives
the line number on which it occurred as it's first argument, it doesn't pass
on this line number to the argument list of the action. I'll submit a
follow-on rfc patch for this. ]

Tested pr45882.c.  Tested one test-case with relative line numbers, and
one with line number variables to make sure I didn't break process-message.

OK for trunk if bootstrap and reg-test succeeds?

Thanks,
- Tom

[testsuite/guality] Use line number vars in gdb-test

2018-06-28  Tom de Vries  <tdevries@suse.de>

	* gcc.dg/guality/pr45882.c (foo): Add line number var for breakpoint
	line, and use it.
	* lib/gcc-dg.exp (get-absolute-line): Factor out of ...
	(process-message): ... here.
	* lib/gcc-gdb-test.exp (gdb-test): Use get-absolute-line.

---
 gcc/testsuite/gcc.dg/guality/pr45882.c | 10 ++---
 gcc/testsuite/lib/gcc-dg.exp           | 73 +++++++++++++++++++++-------------
 gcc/testsuite/lib/gcc-gdb-test.exp     |  3 +-
 3 files changed, 52 insertions(+), 34 deletions(-)

[ resending. It seems this did not get through to the mail archive. ]

On Thu, Jun 28, 2018 at 07:49:30PM +0200, Tom de Vries wrote:
> Hi,
> 
> I played around with pr45882.c and ran into FAILs.  It took me a while to
> realize that the FAILs where due to the gdb-test (a dg-final action) using
> absolute line numbers, and me adding lines before the gdb-test lines.
> 
> I've written this patch, which factors out the handling of relative line
> numbers as well as line number variables from process-message, and reuses the
> functionality in gdb-test.
> 
> This enables the line number variables functionality in gdb-test.  [ There's
> one quirk: line number variables have a define-before-use semantics (with
> matching used-before-defined error) but in the test-case the use in gdb-test
> preceeds the definition in gdb-line.  This doesn't cause errors, because
> the dg-final actions are executed after the definition has taken effect. ]
> 
> [ Relative line numbers still don't work in gdb-test, but that's due to an
> orthogonal issue: gdb-test is a dg-final action, and while dg-final receives
> the line number on which it occurred as it's first argument, it doesn't pass
> on this line number to the argument list of the action. I'll submit a
> follow-on rfc patch for this. ]
> 
> Tested pr45882.c.  Tested one test-case with relative line numbers, and
> one with line number variables to make sure I didn't break process-message.
> 
> OK for trunk if bootstrap and reg-test succeeds?
> 
> Thanks,
> - Tom
> 
> [testsuite/guality] Use line number vars in gdb-test
> 
> 2018-06-28  Tom de Vries  <tdevries@suse.de>
> 
> 	* gcc.dg/guality/pr45882.c (foo): Add line number var for breakpoint
> 	line, and use it.
> 	* lib/gcc-dg.exp (get-absolute-line): Factor out of ...
> 	(process-message): ... here.
> 	* lib/gcc-gdb-test.exp (gdb-test): Use get-absolute-line.
> 
> ---
>  gcc/testsuite/gcc.dg/guality/pr45882.c | 10 ++---
>  gcc/testsuite/lib/gcc-dg.exp           | 73 +++++++++++++++++++++-------------
>  gcc/testsuite/lib/gcc-gdb-test.exp     |  3 +-
>  3 files changed, 52 insertions(+), 34 deletions(-)
> 
> diff --git a/gcc/testsuite/gcc.dg/guality/pr45882.c b/gcc/testsuite/gcc.dg/guality/pr45882.c
> index ece35238a30..da9e2755590 100644
> --- a/gcc/testsuite/gcc.dg/guality/pr45882.c
> +++ b/gcc/testsuite/gcc.dg/guality/pr45882.c
> @@ -9,11 +9,11 @@ volatile short int v;
>  __attribute__((noinline,noclone,used)) int
>  foo (int i, int j)
>  {
> -  int b = i;		/* { dg-final { gdb-test 16 "b" "7" } } */
> -  int c = i + 4;	/* { dg-final { gdb-test 16 "c" "11" } } */
> -  int d = a[i];		/* { dg-final { gdb-test 16 "d" "112" } } */
> -  int e = a[i + 6];	/* { dg-final { gdb-test 16 "e" "142" } } */
> -  ++v;
> +  int b = i;		/* { dg-final { gdb-test bpline "b" "7" } } */
> +  int c = i + 4;	/* { dg-final { gdb-test bpline "c" "11" } } */
> +  int d = a[i];		/* { dg-final { gdb-test bpline "d" "112" } } */
> +  int e = a[i + 6];	/* { dg-final { gdb-test bpline "e" "142" } } */
> +  ++v;			/* { dg-line bpline } */
>    return ++j;
>  }
>  
> diff --git a/gcc/testsuite/lib/gcc-dg.exp b/gcc/testsuite/lib/gcc-dg.exp
> index a15c5d5e2a6..22065c7e3fe 100644
> --- a/gcc/testsuite/lib/gcc-dg.exp
> +++ b/gcc/testsuite/lib/gcc-dg.exp
> @@ -1039,6 +1039,49 @@ proc dg-line { linenr varname } {
>      }
>  }
>  
> +# Get the absolute line number corresponding to:
> +# - a relative line number (a non-null useline is required), or
> +# - a line number variable reference.
> +# Argument 0 is the line number on which line was used
> +# Argument 1 is the relative line number or line number variable reference
> +#
> +proc get-absolute-line { useline line } {
> +    if { [regsub "^\.\[+-\](\[0-9\]+)$" $line "\\1" num] && $useline != "" } {
> +	# Handle relative line specification, .+1 or .-1 etc.
> +	set num [expr $useline [string index $line 1] $num]
> +	return $num
> +    }
> +
> +    if { ! [regsub "^(\[a-zA-Z\]\[a-zA-Z0-9_\]*)$" $line "\\1" varname] } {
> +	return $line
> +    }
> +
> +    # Handle linenr variable defined by dg-line
> +    set org_varname $varname
> +    set varname "saved_linenr_$varname"
> +    eval global $varname
> +
> +    # Generate used-but-not-defined error.
> +    eval set var_defined [info exists $varname]
> +    if { ! $var_defined } {
> +	if { "$useline" != "" } {
> +	    error "dg-line var $org_varname used at line $uselinenr, but not defined"
> +	} else {
> +	    error "dg-line var $org_varname used, but not defined"
> +	}
> +	return
> +    }
> +
> +    # Note that varname has been used.
> +    set varname_used "used_$varname"
> +    eval global $varname_used
> +    eval set $varname_used 1
> +
> +    # Get line number from var and use it.
> +    eval set num \$$varname
> +    set line $num
> +}
> +
>  # Modify the regular expression saved by a DejaGnu message directive to
>  # include a prefix and to force the expression to match a single line.
>  # MSGPROC is the procedure to call.
> @@ -1049,34 +1092,8 @@ proc process-message { msgproc msgprefix dgargs } {
>      upvar dg-messages dg-messages
>  
>      if { [llength $dgargs] == 5 } {
> -	if { [regsub "^\.\[+-\](\[0-9\]+)$" [lindex $dgargs 4] "\\1" num] } {
> -	    # Handle relative line specification, .+1 or .-1 etc.
> -	    set num [expr [lindex $dgargs 0] [string index [lindex $dgargs 4] 1] $num]
> -	    set dgargs [lreplace $dgargs 4 4 $num]
> -	} elseif { [regsub "^(\[a-zA-Z\]\[a-zA-Z0-9_\]*)$" [lindex $dgargs 4] "\\1" varname] } {
> -	    # Handle linenr variable defined by dg-line
> -
> -	    set org_varname $varname
> -	    set varname "saved_linenr_$varname"
> -	    eval global $varname
> -
> -	    # Generate used-but-not-defined error.
> -	    eval set var_defined [info exists $varname]
> -	    if { ! $var_defined } {
> -		set linenr [expr [lindex $dgargs 0]]
> -		error "dg-line var $org_varname used at line $linenr, but not defined"
> -		return
> -	    }
> -
> -	    # Note that varname has been used.
> -	    set varname_used "used_$varname"
> -	    eval global $varname_used
> -	    eval set $varname_used 1
> -
> -	    # Get line number from var and use it.
> -	    eval set num \$$varname
> -	    set dgargs [lreplace $dgargs 4 4 $num]
> -	}
> +	set num [get-absolute-line [lindex $dgargs 0] [lindex $dgargs 4]]
> +	set dgargs [lreplace $dgargs 4 4 $num]
>      }
>  
>      # Process the dg- directive, including adding the regular expression
> diff --git a/gcc/testsuite/lib/gcc-gdb-test.exp b/gcc/testsuite/lib/gcc-gdb-test.exp
> index 2ef9ca15c12..5457e7a793e 100644
> --- a/gcc/testsuite/lib/gcc-gdb-test.exp
> +++ b/gcc/testsuite/lib/gcc-gdb-test.exp
> @@ -60,7 +60,8 @@ proc gdb-test { args } {
>      set cmd_file "[file rootname [file tail $prog]].gdb"
>  
>      set fd [open $cmd_file "w"]
> -    puts $fd "break [lindex $args 0]"
> +    set line [get-absolute-line "" [lindex $args 0]]
> +    puts $fd "break $line"
>      puts $fd "run"
>      puts $fd "$command $var"
>      if { $command == "print" } {

On 06/28/2018 11:49 AM, Tom de Vries wrote:
> Hi,
> 
> I played around with pr45882.c and ran into FAILs.  It took me a while to
> realize that the FAILs where due to the gdb-test (a dg-final action) using
> absolute line numbers, and me adding lines before the gdb-test lines.
> 
> I've written this patch, which factors out the handling of relative line
> numbers as well as line number variables from process-message, and reuses the
> functionality in gdb-test.
> 
> This enables the line number variables functionality in gdb-test.  [ There's
> one quirk: line number variables have a define-before-use semantics (with
> matching used-before-defined error) but in the test-case the use in gdb-test
> preceeds the definition in gdb-line.  This doesn't cause errors, because
> the dg-final actions are executed after the definition has taken effect. ]
> 
> [ Relative line numbers still don't work in gdb-test, but that's due to an
> orthogonal issue: gdb-test is a dg-final action, and while dg-final receives
> the line number on which it occurred as it's first argument, it doesn't pass
> on this line number to the argument list of the action. I'll submit a
> follow-on rfc patch for this. ]
> 
> Tested pr45882.c.  Tested one test-case with relative line numbers, and
> one with line number variables to make sure I didn't break process-message.
> 
> OK for trunk if bootstrap and reg-test succeeds?
> 
> Thanks,
> - Tom
> 
> [testsuite/guality] Use line number vars in gdb-test
> 
> 2018-06-28  Tom de Vries  <tdevries@suse.de>
> 
> 	* gcc.dg/guality/pr45882.c (foo): Add line number var for breakpoint
> 	line, and use it.
> 	* lib/gcc-dg.exp (get-absolute-line): Factor out of ...
> 	(process-message): ... here.
> 	* lib/gcc-gdb-test.exp (gdb-test): Use get-absolute-line.
I prefer the relative line numbers, but either approach is fine with me.
 Your call.

jeff