compat.exp

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# Copyright (C) 2002 Free Software Foundation, Inc.

# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.

# This file was written by Janis Johnson, <[e-mail]>


# Test interoperability of two compilers that follow the same ABI, or
# compatibility of two versions of GCC.
#
# Each test has a main program that does nothing but call a function,
# plus two additional source files that contain parts of a program that
# rely on the ABI.  those source files are compiled into relocatable
# object files with both compilers.  Executables are built using various
# combinations of those object files, with the main program compiled
# with the compiler under test and using that compiler's runtime support.

# The including .exp file must define these callback procedures.
if [string match "" [info procs "compat-use-alt-compiler"]] then {
    error "Proc compat-use-alt-compiler is not defined."
}
if [string match "" [info procs "compat-use-tst-compiler"]] then {
    error "Proc compat-use-tst-compiler is not defined."
}

# Each test is run with each pair of compiler options from this list.
# The first set of options in each pair is used by the compiler under
# test, and the second set is used by the alternate compiler.
# The default option lists can be overridden by
# COMPAT_OPTIONS="[list [list {tst_1} {alt_1}]...[list {tst_n} {alt_n}]]"
# where tst_i and alt_i are lists of options.  You can put this in the
# environment before site.exp is written or add it to site.exp directly.
if ![info exists COMPAT_OPTIONS] {
    set COMPAT_OPTIONS [list \
	[list {} {}]]
}

set option_list $COMPAT_OPTIONS

#
# compat-obj -- compile to an object file
#
# SOURCE is the source file
# DEST is the object file
# OPTIONS is the list of compiler options
# OPTSTR is the options to print with test messages
#
proc compat-obj { source dest options optstr } {
    global testcase
    global tool

    set comp_output [${tool}_target_compile "$source" "$dest" object $options]
    ${tool}_check_compile "$testcase $dest compile" $optstr $dest $comp_output
}

# compat-run -- link and run an executable
#
# TESTNAME is the mixture of object files to link
# OBJLIST is the list of object files to link
# DEST is the name of the executable
# OPTIONS is a list of compiler and linker options to use
# OPTSTR is the list of options to list in messages
#
proc compat-run { testname objlist dest options optstr } {
    global testcase
    global tool

    # Check that all of the objects were built successfully.
    foreach obj [split $objlist] {
	if ![file exists $obj] then {
	    unresolved "$testcase $testname link $optstr"
	    unresolved "$testcase $testname execute $optstr"
	    return
	}
    }

    # Link the objects into an executable.
    set comp_output [${tool}_target_compile "$objlist" $dest executable \
		     "$options"]
    if ![${tool}_check_compile "$testcase $testname link" "" \
	 $dest $comp_output] then {
	unresolved "$testcase $testname execute $optstr"
	return
    }

    # Run the self-checking executable.
    if ![string match "*/*" $dest] then {
	set dest "./$dest"
    }
    set result [${tool}_load $dest "" ""]
    set status [lindex $result 0]
    if { $status == "pass" } then {
	remote_file build delete $dest
    }
    $status "$testcase $testname execute $optstr"
}

#
# compat-execute -- compile with compatible compilers
#
# SRC1 is the full pathname of the main file of the testcase.
# USE_ALT is nonzero if we're using an alternate compiler as well as
#   the compiler under test.
#
proc compat-execute { src1 use_alt } {
    global srcdir tmpdir
    global option_list
    global tool
    global verbose
    global testcase
    global gluefile

    # Use the dg-options mechanism to specify extra flags for this test.
    # FIXME: This does not handle other uses of dg-options, and it only
    # processes the first one.
    set extra_tool_flags ""
    set tmp [grep $src1 "{\[ \t\]\*dg-options.*\[ \t\]\+}"]
    if ![string match "" $tmp] {
	set tmp0 [lindex $tmp 0]
	# Extract the compiler options.
	regexp "dg-options\[ \t\]\+(.*)\[ \t\]\+\}" \
	       $tmp0 all args
	# Sometime the options are in quotes, sometimes not.
	regsub -all "\"" $args "" args
	set extra_tool_flags $args
    }

    # Set up the names of the other source files.
    regsub "_main.*" $src1 "" base
    regsub ".*/" $base "" base
    regsub "_main" $src1 "_x" src2
    regsub "_main" $src1 "_y" src3

    # Define the names of the object files.
    set obj1 "main_tst.o"
    set obj2_tst "x_tst.o"
    set obj2_alt "x_alt.o"
    set obj3_tst "y_tst.o"
    set obj3_alt "y_alt.o"

    # Get the base name of this test, for use in messages.
    regsub "^$srcdir/?" $src1 "" testcase
    regsub "_main.*" $testcase "" testcase
    # Set up the base name of executable files so they'll be unique.
    regsub -all "\[./\]" $testcase "-" execbase

    # If we couldn't rip $srcdir out of `src1' then just do the best we can.
    # The point is to reduce the unnecessary noise in the logs.  Don't strip
    # out too much because different testcases with the same name can confuse
    # `test-tool'.
    if [string match "/*" $testcase] then {
        set testcase "[file tail [file dirname $src1]]/[file tail $src1]"
    }

    # Loop through all of the option lists used for this test.

    set count 0
    foreach option_pair $option_list {

	# Pick out each set of options.
	set tst_option [lindex $option_pair 0]
	set alt_option [lindex $option_pair 1]
	set optstr ""
	if { ![string match $tst_option ""] \
	     || ![string match $alt_option ""] } then {
	    set optstr "\"$tst_option\",\"$alt_option\""
	}
	verbose "Testing $testcase, $optstr" 1

	set tst_options ""
	set alt_options ""
	if ![string match $extra_tool_flags ""] then {
	    lappend tst_options "additional_flags=$extra_tool_flags $tst_option"
	    lappend alt_options "additional_flags=$extra_tool_flags $alt_option"
	}

	# There's a unique name for each executable we generate, based on
	# the set of options and how the pieces of the tests are compiled.
	set execname1 "${execbase}-${count}1"
	set execname2 "${execbase}-${count}2"
	set execname3 "${execbase}-${count}3"
	set execname4 "${execbase}-${count}4"
	incr count

	remote_file build delete $execname1
	remote_file build delete $execname2
	remote_file build delete $execname3
	remote_file build delete $execname4

	# Compile pieces with the alternate compiler; we'll catch problems
	# later.  Skip this if we don't have an alternate compiler.
	if { $use_alt != 0 } then {
	    compat-use-alt-compiler
	    compat-obj "$src2" "$obj2_alt" $alt_options $optstr
	    compat-obj "$src3" "$obj3_alt" $alt_options $optstr
	}

	# Compile pieces with the compiler under test.
	compat-use-tst-compiler
	compat-obj "$src1" "$obj1" $tst_options $optstr
	compat-obj "$src2" "$obj2_tst" $tst_options $optstr
	compat-obj "$src3" "$obj3_tst" $tst_options $optstr

	# Link (using the compiler under test), run, and clean up tests.
	compat-run "${obj2_tst}-${obj3_tst}" \
	    "$obj1 $obj2_tst $obj3_tst" $execname1 $tst_options $optstr

	# If we've got an alternate compiler try some combinations.
	if { $use_alt != 0 } then {
	    compat-run "${obj2_tst}-${obj3_alt}" "$obj1 $obj2_tst $obj3_alt" \
		       $execname2 $tst_options $optstr
	    compat-run "${obj2_alt}-${obj3_tst}" "$obj1 $obj2_alt $obj3_tst" \
		       $execname3 $tst_options $optstr
	    compat-run "${obj2_alt}-${obj3_alt}" "$obj1 $obj2_alt $obj3_alt" \
		       $execname4 $tst_options $optstr
	}

	# Clean up object files.
	set files [glob -nocomplain *.o]
	if { $files != "" } {
	    foreach objfile $files {
		if { ![info exists gluefile] || $objfile != $gluefile } {
		    eval "remote_file build delete $objfile"
		}
	    }
	}
    }
}