Re: [PATCH] testsuite: Fix subexpressions with `scan-assembler-times'

[Jeff Law <jeffreyalaw@gmail.com>]

On 11/19/23 04:27, Maciej W. Rozycki wrote:
> We have an issue with `scan-assembler-times' handling expressions using
> subexpressions as produced by capturing parentheses `()' in an odd way,
> and one that is inconsistent with `scan-assembler', `scan-assembler-not',
> etc.  The problem comes from calling `regexp' with `-inline -all', which
> causes a list to be returned that would otherwise be placed in match
> variables.
> 
> Consequently if we have say:
> 
> /* { dg-final { scan-assembler-times "\\s(foo|bar)\\s" 1 } } */
> 
> in a test case and there is a lone `foo' present in output being matched,
> then our invocation of `regexp -inline -all' in `scan-assembler-times'
> will return:
> 
> { foo } foo
> 
> and that in turn will confuse our match count calculation as `llength'
> will return 2 rather than 1, making the test fail even though `foo' was
> only actually matched once.
> 
> It seems unclear why we chose to call `regexp' in such an odd way in the
> first place just to figure out the number of matches.  The first version
> of TCL that supports the `-all' option to `regexp' is 8.3, and according
> to its documentation[1][2] `regexp' already returns the number of matches
> found whenever `-all' has been used *unless* `-inline' has also been used.
> 
> Remove the `-inline' option then along with the `llength' invocation.
> 
> References:
> 
> [1] "Tcl Built-In Commands - regexp manual page",
>      <https://www.tcl.tk/man/tcl8.2.3/TclCmd/regexp.html>
> 
> [2] "Tcl Built-In Commands - regexp manual page",
>      <https://www.tcl.tk/man/tcl8.3/TclCmd/regexp.html>
> 
> 	gcc/testsuite/
> 	* lib/scanasm.exp (scan-assembler-times): Remove the `-inline'
> 	option to `regexp' and the wrapping `llength' call.
> ---
> Hi,
> 
>   Verified with the `riscv64-linux-gnu' target and the C language
> testsuite.  OK to apply?
Not sure why it is the way it is -- I walked back to Zdenek's change 
which introduced the scan-assembler-times and nothing about the -inline 
argument.

OK, but be on the lookout for scan-asm problems on other targets over 
the next few days.

Jeff