[PATCH] testsuite: Add support for scanning assembly with comparitor

2024-02-12 Thread Edwin Lu
There is currently no support for matching at least x lines of assembly
(only scan-assembler-times). This patch would allow setting upper or lower
bounds.

Use case: using different scheduler descriptions and/or cost models will change
assembler output. Testing common functionality across tunes would require a
separate testcase per tune since each assembly output would be different. If we
know a base number of lines should appear across all tunes (i.e. testing return
values: we expect at minimum n stores into register x), we can lower-bound the
test to search for scan-assembler-bound {RE for storing into register x} >= n.
This avoids artificially inflating the scan-assembler-times expected count due
to the assembler choosing to perform extra stores into register x (using it as
a temporary register).

The testcase would be more robust to cpu/tune changes at the cost of not being
as granular towards specific cpu tuning.

gcc/ChangeLog:

* doc/sourcebuild.texi: add scan-assembler-bound

gcc/testsuite/ChangeLog:

* lib/scanasm.exp: add scan-assembler-bound

Signed-off-by: Edwin Lu 
---
 gcc/doc/sourcebuild.texi  |  4 +++
 gcc/testsuite/lib/scanasm.exp | 64 +++
 2 files changed, 68 insertions(+)

diff --git a/gcc/doc/sourcebuild.texi b/gcc/doc/sourcebuild.texi
index 193be19767f..4a8c672c9fd 100644
--- a/gcc/doc/sourcebuild.texi
+++ b/gcc/doc/sourcebuild.texi
@@ -3396,6 +3396,10 @@ excluding LTO sections.
 Passes if @var{regex} is matched exactly @var{num} times in the test's
 assembler output, excluding LTO sections.
 
+@item scan-assembler-bound @var{regex} @var{cmp} @var{num} [@{ target/xfail 
@var{selector} @}]
+Passes if @var{regex} is matched @var{cmp} @var{num} times in the test's
+assembler output, excluding LTO sections. @var{cmp} is a comparitor.
+
 @item scan-assembler-dem @var{regex} [@{ target/xfail @var{selector} @}]
 Passes if @var{regex} matches text in the test's demangled assembler output,
 excluding LTO sections.
diff --git a/gcc/testsuite/lib/scanasm.exp b/gcc/testsuite/lib/scanasm.exp
index 165890eb976..741a5a048b8 100644
--- a/gcc/testsuite/lib/scanasm.exp
+++ b/gcc/testsuite/lib/scanasm.exp
@@ -516,6 +516,70 @@ proc scan-assembler-times { args } {
 
 set_required_options_for scan-assembler-times
 
+# Call pass if pattern is present within a lower or upper bound, 
+# otherwise fail.
+# ex /* { dg-final { scan-assembler-bound {RE} > 3 } }
+proc scan-assembler-bound { args } {
+if { [llength $args] < 3 } {
+   error "scan-assembler-bound: too few arguments"
+return
+}
+if { [llength $args] > 4 } {
+   error "scan-assembler-bound: too many arguments"
+   return
+}
+if { [llength $args] >= 4 } {
+   switch [dg-process-target [lindex $args 3]] {
+   "S" { }
+   "N" { return }
+   "F" { setup_xfail "*-*-*" }
+   "P" { }
+   }
+}
+
+set testcase [testname-for-summary]
+# The name might include a list of options; extract the file name.
+set filename [lindex $testcase 0]
+set pattern [lindex $args 0]
+set cmp [lindex $args 1]
+set bound [lindex $args 2]
+set pp_pattern [make_pattern_printable $pattern]
+
+# This must match the rule in gcc-dg.exp.
+set output_file "[file rootname [file tail $filename]].s"
+
+set files [glob -nocomplain $output_file]
+if { $files == "" } {
+   verbose -log "$testcase: output file does not exist"
+   unresolved "$testcase scan-assembler-bound $pp_pattern $min $max"
+   return
+}
+
+if { [lsearch { < > <= >= } $cmp] == -1 } {
+error "scan-assembler-bound: illegal argument: $cmp"
+return
+}
+if ![string is integer $bound ] {
+error "scan-assembler-bound: illegal argument: $bound"
+return
+}
+
+set fd [open $output_file r]
+set text [read $fd]
+close $fd
+regsub -all 
{(^|\n)[[:space:]]*\.section[[:space:]]*"?\.gnu\.lto_(?:[^\n]*\n(?![[:space:]]*\.(section|text|data|bss)))*[^\n]*\n}
 $text {\1} text
+
+set result_count [regexp -all -- $pattern $text]
+if [expr $result_count $cmp $bound] {
+   pass "$testcase scan-assembler-bound $pp_pattern $cmp $bound"
+} else {
+   verbose -log "$testcase: $pp_pattern found $result_count times"
+   fail "$testcase scan-assembler-bound $pp_pattern $cmp $bound"
+}
+}
+
+set_required_options_for scan-assembler-bound
+
 # Utility for scanning demangled compiler result, invoked via dg-final.
 # Call pass if pattern is present, otherwise fail.
 proc scan-assembler-dem { args } {
-- 
2.34.1



Re: [PATCH] testsuite: Add support for scanning assembly with comparitor

2024-02-15 Thread Mike Stump
On Feb 12, 2024, at 11:38 AM, Edwin Lu  wrote:
> 
> There is currently no support for matching at least x lines of assembly
> (only scan-assembler-times). This patch would allow setting upper or lower
> bounds.
> 
> Use case: using different scheduler descriptions and/or cost models will 
> change
> assembler output. Testing common functionality across tunes would require a
> separate testcase per tune since each assembly output would be different. If 
> we
> know a base number of lines should appear across all tunes (i.e. testing 
> return
> values: we expect at minimum n stores into register x), we can lower-bound the
> test to search for scan-assembler-bound {RE for storing into register x} >= n.
> This avoids artificially inflating the scan-assembler-times expected count due
> to the assembler choosing to perform extra stores into register x (using it as
> a temporary register).
> 
> The testcase would be more robust to cpu/tune changes at the cost of not being
> as granular towards specific cpu tuning.

I didn't see an Ok?  Just in case you forgot, yes, this is ok.