# Copyright (C) 2002-2021 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 3 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 GCC; see the file COPYING3.  If not see
# <http://www.gnu.org/licenses/>.

# Please email any bugs, comments, and/or additions to this file to:
# gcc-patches@gcc.gnu.org

# Globals.

global compat_use_alt
global compat_same_alt
global compat_have_dfp
global compat_skip_list

# This file defines procs for determining features supported by both C
# compilers for compatibility tests.

load_lib target-supports.exp
load_lib target-libpath.exp

#
# compat-use-alt-compiler -- make the alternate compiler the default
# 
proc compat-use-alt-compiler { } {
    global GCC_UNDER_TEST ALT_CC_UNDER_TEST
    global compat_same_alt compat_alt_caret compat_alt_color compat_no_line_no
    global compat_alt_urls compat_alt_plain_output
    global TEST_ALWAYS_FLAGS

    # We don't need to do this if the alternate compiler is actually
    # the same as the compiler under test.
    if { $compat_same_alt == 0 } then {
	set GCC_UNDER_TEST $ALT_CC_UNDER_TEST

	# These flags are no longer added to TEST_ALWAYS_FLAGS by prune.exp
	# because they are subsumed by -fdiagnostics-plain-output. Add them back
	# for compatibility testing with older compilers that do not understand
	# -fdiagnostics-plain-output.
	set TEST_ALWAYS_FLAGS "-fno-diagnostics-show-caret -fno-diagnostics-show-line-numbers -fdiagnostics-color=never -fdiagnostics-urls=never $TEST_ALWAYS_FLAGS"

	if { $compat_alt_caret == 0 } then {
	    regsub -all -- "-fno-diagnostics-show-caret" $TEST_ALWAYS_FLAGS "" TEST_ALWAYS_FLAGS
	}
	if { $compat_alt_color == 0 } then {
	    regsub -all -- "-fdiagnostics-color=never" $TEST_ALWAYS_FLAGS "" TEST_ALWAYS_FLAGS
	}
	if { $compat_alt_urls == 0 } then {
	    regsub -all -- "-fdiagnostics-urls=never" $TEST_ALWAYS_FLAGS "" TEST_ALWAYS_FLAGS
	}
	if { $compat_no_line_no == 0 } then {
	    regsub -all -- "-fno-diagnostics-show-line-numbers" $TEST_ALWAYS_FLAGS "" TEST_ALWAYS_FLAGS
	}
	if { $compat_alt_plain_output == 0 } then {
	    regsub -all -- "-fdiagnostics-plain-output" $TEST_ALWAYS_FLAGS "" TEST_ALWAYS_FLAGS
	}
	restore_gcc_exec_prefix_env_var
    }
}

#
# compat-use-tst-compiler -- make compiler under test the default
#
proc compat-use-tst-compiler { } {
    global GCC_UNDER_TEST compat_save_gcc_under_test
    global compat_same_alt
    global TEST_ALWAYS_FLAGS compat_save_TEST_ALWAYS_FLAGS

    # We don't need to do this if the alternate compiler is actually
    # the same as the compiler under test.

    if { $compat_same_alt == 0 } then {
	set GCC_UNDER_TEST $compat_save_gcc_under_test
	set TEST_ALWAYS_FLAGS $compat_save_TEST_ALWAYS_FLAGS
	set_gcc_exec_prefix_env_var
    }
}

# Find out whether both compilers support decimal float types.
proc compat_setup_dfp { } {
    global compat_use_alt
    global compat_same_alt
    global compat_have_dfp
    global compat_alt_caret
    global compat_alt_color
    global compat_alt_urls
    global compat_alt_plain_output
    global compat_no_line_no
    global TEST_ALWAYS_FLAGS compat_save_TEST_ALWAYS_FLAGS

    set compat_alt_caret 0
    set compat_alt_color 0
    set compat_alt_urls 0
    set compat_alt_plain_output 0
    set compat_no_line_no 0
    set compat_save_TEST_ALWAYS_FLAGS $TEST_ALWAYS_FLAGS

    verbose "compat_setup_dfp: $compat_use_alt $compat_same_alt" 2

    # Does the compiler under test support decimal float types?
    compat-use-tst-compiler
    set compat_have_dfp [check_effective_target_dfprt_nocache]
    verbose "compat_have_dfp for tst compiler: $compat_have_dfp" 2

    if { $compat_use_alt == 1 && $compat_same_alt == 0 } {
	compat-use-alt-compiler
	if { [check_no_compiler_messages_nocache compat_alt_has_caret object {
		int dummy; } "-fno-diagnostics-show-caret"] != 0 } {
	    set compat_alt_caret 1
	}
	if { [check_no_compiler_messages_nocache compat_alt_has_color object {
		int dummy; } "-fdiagnostics-color=never"] != 0 } {
	    set compat_alt_color 1
	}
	if { [check_no_compiler_messages_nocache compat_alt_has_urls object {
		int dummy; } "-fdiagnostics-urls=never"] != 0 } {
	    set compat_alt_urls 1
	}
	if { [check_no_compiler_messages_nocache compat_alt_has_no_line_no object {
		int dummy; } "-fno-diagnostics-show-line-numbers"] != 0 } {
	    set compat_no_line_no 1
	}
	if { [check_no_compiler_messages_nocache compat_alt_has_plain_output object {
		int dummy; } "-fdiagnostics-plain-output"] != 0 } {
	    set compat_alt_plain_output 1
	}
	
	compat-use-tst-compiler
    }

    # If there is an alternate compiler, does it support decimal float types?
    if { $compat_have_dfp == 1 && $compat_use_alt == 1 && $compat_same_alt == 0 } {
	compat-use-alt-compiler
	set compat_have_dfp [check_effective_target_dfprt_nocache]
	compat-use-tst-compiler
	verbose "compat_have_dfp for alt compiler: $compat_have_dfp" 2
    }

    # If decimal float is not supported, add it to the skip list, which
    # affects code in the header files.
    if { $compat_have_dfp == 0 } {
	global compat_skip_list
	lappend compat_skip_list "DECIMAL_FLOAT"
    }
}

# If either compiler does not support decimal float types, skip this test.

proc dg-require-compat-dfp { args } {
    global compat_have_dfp
    if { $compat_have_dfp == 0 } {
	upvar dg-do-what dg-do-what
	set dg-do-what [list [lindex ${dg-do-what} 0] "N" "P"]
    }
}