[patch] testsuite: new proc dg-target-list

[Janis Johnson <janis187 at us dot ibm dot com>]

This patch adds proc dg-target-list which can be used in dg- commands
that expect a target list, possibly preceded by the keyword "target" or
"xfail".  Its first argument is the keyword, or "" for no keyword, and
the second argument is a 1 or 0 that is the result of a TCL conditional
expression.  It allows a lot of flexibility for specifying target lists
since the expression can include combinations of [istarget xxx] and
[check-whatever].

Some of examples of how this could be used in actual tests:

{ dg-do run [dg-target-list target [expr [istarget powerpc*-*-linux*] && [check_effective_target lp64]]] }

{ dg-xfail-if "" [dg-target-list "" [expr [check_effective_target ilp32] && [expr [istarget sparc*-*-*] || [istarget powerpc*-*-*]]]] { "*" } { "" } }

{ dg-final { scan-assembler "something" [dg-target-list xfail [check_gc_sections_available]] } }

My earlier versions of this were much more complex but then I figured
out how to get TCL to do most of the work.  There might be a way to do
this without even using dg-target-list, but if so I haven't found it.

I've tested this with an expanded version of my generated test framework
tests, which I'll post shortly (I posted a smaller version a few days
ago).

OK for mainline?

2004-11-05  Janis Johnson  <janis187@us.ibm.com>

	* lib/gcc-dg.exp (dg-target-list): New

--- lib/gcc-dg.exp.orig	2004-11-04 18:16:39.000000000 -0800
+++ lib/gcc-dg.exp	2004-11-04 18:17:10.000000000 -0800
@@ -453,6 +453,25 @@ proc dg-xfail-if { args } {
     }
 }
 
+# Given an optional keyword "target" or "fail" and the result of a
+# condition which has been evaluated by the framework, return a list
+# containing the keyword and "*-*-*" if the condition is true or
+# "empty-empty-empty" if the condition is false.
+
+proc dg-target-list { what cond } {
+    switch $what {
+	"target" { set result [list $what] }
+	"xfail"  { set result [list $what] }
+	""       { set result [list] }
+	default  { error "`$what' not allowed here" }
+    }
+    if { $cond } {
+	lappend result "*-*-*"
+    } else {
+	lappend result "empty-empty-empty"
+    }
+    return $result
+}
 
 # We need to make sure that additional_* are cleared out after every
 # test.  It is not enough to clear them out *before* the next test run