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# Copyright (C) 1997, 2007, 2008, 2009 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

# .

# A MIPS version of the GCC dg.exp driver.

#

# There are many MIPS features that we want to test, and many of those

# features are specific to certain architectures, certain ABIs and so on.

# There are therefore many cases in which we want to test something that

# is incompatible with the user's chosen test options.

#

# In most dg testsuites, the options added by dg-options have a lower

# priority than the options chosen by the user.  For example, if a test

# specifies:

#

#    { dg-options "-mips1" }

#

# and the user passes the following option to runtest:

#

#    --target_board unix/-mips3

#

# the test would be compiled as MIPS III rather than MIPS I.  If the

# test really wouldn't work with -mips3, normal practice would be to

# have something like:

#

#    { dg-do compile { target can_force_mips1 } }

#

# so that the test is skipped when an option like -mips3 is passed.

#

# Sticking to the same approach here would cause us to skip many tests,

# even though the toolchain can generate the required code.  For example,

# there are 6 MIPS ABIs, plus variants.  Some configurations support

# more than one ABI, so it is natural to use something like:

#

#    --target_board unix{-mabi=n32,-mabi=32,-mabi=64}

#

# when testing them.  But these -mabi=* options would normally prevent any

# EABI and o64 tests from running.

#

# This testsuite therefore defines a local version of dg-options that

# overrides any user options that are incompatible with the test options.

# It tries to keep the other user options intact.

#

#

# Most of the tests in this testsuite are scan-assembler tests, but

# sometimes we need a link test instead.  In these cases, we must not

# try to link code with options that are incompatible with the current

# multilib, because xgcc is passed -L and -B options that are specific

# to that multilib.

#

# Normal GCC practice would be to skip incompatible link tests as

# unsupported, but in this particular case, it seems better to downgrade

# them to an assemble test instead.  At least that way we get some

# test-for-ICE and code-sanity coverage.

#

# The same problem applies to run tests.  If a test requires runtime

# support for a particular feature, and if the current target does not

# provide that support, normal practice would be to skip the test.

# But in this case it seems better to downgrade it to a link test instead.

# (We might then have to downgrade it to an assembler test according to

# the constraints just mentioned.)

#

# The local dg-options therefore checks whether the new options are

# link-compatiable with the user's options.  If not, it automatically

# downgrades link tests to assemble tests.  It does the same for run

# tests, but in addition, it downgrades run tests to link tests if the

# target does not provide runtime support for a required feature or ASE.

#

#

# Another problem is that many of the options we want to test require

# certain other features.  For example, -mips3d requires both 64-bit

# FPRs and a MIPS32 or MIPS64 target; -mfix-r10000 requires branch-

# likely instructions; and so on.  We could handle this by specifying

# a set of options that are guaranteed to give us what we want, such as:

#

#   dg-options "-mips3d -mpaired-single -mhard-float -mgp64 -mfp64 -mabi=n32 -march=mips64 -mips64"

#

# With the new dg-options semantics, this would override any troublesome

# user options like -mips3, -march=vr4100, -mfp32, -mgp32, -msoft-float,

# -mno-paired-single and so on.  But there are three major problems with

# this:

#

#   - It is easy to forget options.

#

#   - If a new option is added, all tests that are incompatible with that

#     option must be updated.

#

#   - We want to be able to test MIPS-3D with things like -march=mips32,

#     -march=mips64r2, -march=sb1, and so on.

#

# The local version of dg-options therefore works out the requirements

# of each test option.  As with the test options themselves, the local

# dg-options overrides any user options that incompatible with these

# requirements, but it keeps the other user options the same.

#

# For example, if the user passes -mips3, a MIPS-3D test will choose

# a different architecture like -mips64 instead.  But if the user

# passes -march=sb1, MIPS-3D tests will be run with that option.

#

#

# Sometimes it is useful to say "I want an environment that is compatible

# with option X, but I don't want to pass option X itself".  The main example

# of this is -mips16: we want to be able to test __attribute__((mips16))

# without requiring the test itself to be compiled as -mips16.  The local

# version of dg-options lets you do this by putting X in parentheses.

# For example:

#

#   { dg-options "(-mips16)" }

#

# selects a MIPS16-compatible target without passing -mips16 itself.

#

# It is also useful to say "any architecture within this ISA range is fine".

# This can be done using special pseudo-options of the form:

#

#   PROP=VALUE PROP<=VALUE PROP>=VALUE

#

# where PROP can be:

#

#   isa:

#       the value of the __mips macro.

#

#   isa_rev:

#       the value of the __mips_isa_rev macro, or 0 if it isn't defined.

#

# For example, "isa_rev>=1" selects a MIPS32 or MIPS64 processor,

# "isa=4" selects a MIPS IV processor, and so on.

#

# There are also the following special pseudo-options:

#

#   isa=loongson

#       select a Loongson processor

#

#   addressing=absolute

#       force absolute addresses to be used

#

#   forbid_cpu=REGEXP

#       forbid processors that match the given regexp; choose a

#       generic ISA instead.

#

#

# In summary:

#

#   (1) Try to avoid { target ... } requirements wherever possible.

#       Specify the requirements as dg-options instead.

#

#   (2) Don't worry about the consequences of (1) for link and run tests.

#       If the test uses { dg-do link } or { dg-do run }, and its

#       dg-options are incompatible with the current target, the

#       testsuite will downgrade them where necessary.

#

#   (3) Try to use the bare minimum of options and leave dg-options

#       to work out the dependencies.  For example, if you want

#       a MIPS-3D test, you should generally just specify -mips3d.

#       Don't specify an architecture option like -mips64 unless

#       the test really doesn't work with -mips32r2, -mips64r2,

#       -march=sb1, etc.

#

#   (4) If you want something compatible with a particular option,

#       but don't want to pass the option itself, wrap that option

#       in parentheses.  In particular, pass '(-mips16)' if you

#       want to use "mips16" attributes.

#

#   (5) When testing a feature of a generic ISA (as opposed to a

#       processor-specific extension), try to use the "isa" and

#       "isa_rev" pseudo-options instead of specific architecture

#       options.  For example, if the feature is present on revision 2

#       processors and above, try to use "isa_rev>=2" instead of

#       "-mips32r2" or "-mips64r2".

#

#   (6) If you need to disable processor-specific extensions use

#       forbid_cpu=REGEXP instead of forcing a generic ISA.

#

#

# Terminology

#

#   Option group or just group:

#      See comment before mips_option_groups.

#

#   Test options:

#      The options specified in dg-options.

#

#   Explicit options:

#      The options that were either passed to runtest as "multilib" options

#      (e.g. -mips4 in --target_board=mips-sim-idt/-mips4) or specified as

#      test options.  Note that options in parenthesis (i.e. (-mips16)) are

#      not explicit and can be omitted depending on the base options.

#

#   Base options:

#      Options that are on by default without being specified in dg-options,

#      e.g. -march=mips64r2 for mipsisa64r2-elf or because they've been

#      passed to runtest as "multilib" options.

#

#   Option array:

#      Many functions in this file work with option arrays.  These are

#      two-dimensional Tcl arrays where the first dimension can have three

#      values: option, explicit_p or test_option_p.  The second dimension is

#      the name of the option group.  "option" contains the name of the

#      option that is in effect from this group.  If no option is active it

#      contains the empty string.  The flags "explicit_p" and "test_option_p"

#      are set for explicit and test options.

# Exit immediately if this isn't a MIPS target.

if ![istarget mips*-*-*] {

    return

}

# Load support procs.

load_lib gcc-dg.exp

# A list of GROUP REGEXP pairs.  Each GROUP represents a logical group of

# options from which only one option should be chosen.  REGEXP matches all

# the options in that group; it is implicitly wrapped in "^(...)$".

set mips_option_groups {

    abi "-mabi=.*"

    addressing "addressing=.*"

    arch "-mips([1-5]|32.*|64.*)|-march=.*|isa(|_rev)(=|<=|>=).*"

    dump_pattern "-dp"

    endianness "-E(L|B)|-me(l|b)"

    float "-m(hard|soft)-float"

    forbid_cpu "forbid_cpu=.*"

    fp "-mfp(32|64)"

    gp "-mgp(32|64)"

    long "-mlong(32|64)"

    mips16 "-mips16|-mno-mips16"

    mips3d "-mips3d|-mno-mips3d"

    optimization "-O(|[0-3s])"

    pic "-f(no-|)(pic|PIC)"

    profiling "-pg"

    small-data "-G[0-9]+"

    warnings "-w"

}

# Add -mfoo/-mno-foo options to mips_option_groups.

foreach option {

    abicalls

    branch-likely

    dsp

    dspr2

    explicit-relocs

    extern-sdata

    fix-r4000

    fix-r10000

    fix-vr4130

    gpopt

    local-sdata

    long-calls

    paired-single

    plt

    shared

    smartmips

    sym32

    synci

    relax-pic-calls

    mcount-ra-address

} {

    lappend mips_option_groups $option "-m(no-|)$option"

}

# Add -mfoo= options to mips_option_groups.

foreach option {

    branch-cost

    code-readable

    r10k-cache-barrier

    tune

} {

    lappend mips_option_groups $option "-m$option=.*"

}

# Add -ffoo/-fno-foo options to mips_option_groups.

foreach option {

    delayed-branch

    fast-math

    finite-math-only

    fixed-hi

    fixed-lo

    lax-vector-conversions

    split-wide-types

    tree-vectorize

} {

    lappend mips_option_groups $option "-f(no-|)$option"

}

# A list of option groups that have an impact on the ABI.

set mips_abi_groups {

    abi

    abicalls

    arch

    endianness

    float

    fp

    gp

    gpopt

    long

    pic

    small-data

}

# mips_option_tests(OPTION) is some assembly code that will run to completion

# on a target that supports OPTION.

set mips_option_tests(-mips16) {

    move $2,$31

    bal 1f

    .set mips16

    jr $31

    .set nomips16

    .align 2

1:

    ori $3,$31,1

    jalr $3

    move $31,$2

}

set mips_option_tests(-mpaired-single) {

    .set mips64

    lui $2,0x3f80

    mtc1 $2,$f0

    cvt.ps.s $f2,$f0,$f0

}

set mips_option_tests(-mips3d) {

    .set mips64

    .set mips3d

    lui $2,0x3f80

    mtc1 $2,$f0

    cvt.ps.s $f2,$f0,$f0

    mulr.ps $f2,$f2,$f2

    rsqrt1.s $f2,$f0

    mul.s $f4,$f2,$f0

    rsqrt2.s $f4,$f4,$f2

    madd.s $f4,$f2,$f2,$f4

}

set mips_option_tests(-mdsp) {

    .set mips64r2

    .set dsp

    addsc $2,$2,$2

}

set mips_option_tests(-mdspr2) {

    .set mips64r2

    .set dspr2

    prepend $2,$3,11

}

# Canonicalize command-line option OPTION.

proc mips_canonicalize_option { option } {

    regsub {^-mips([1-5]|32*|64*)$} $option {-march=mips\1} option

    regsub {^-mel$} $option {-EL} option

    regsub {^-meb$} $option {-EB} option

    regsub {^-O$} $option {-O1} option

    # MIPS doesn't use -fpic and -fPIC to distinguish between code models.

    regsub {^-f(no-|)PIC} $option {-f\1pic} option

    return $option

}

# Return true if OPTION1 and OPTION2 represent the same command-line option.

proc mips_same_option_p { option1 option2 } {

    return [string equal \

                [mips_canonicalize_option $option1] \

                [mips_canonicalize_option $option2]]

}

# Preprocess CODE using target_compile options OPTIONS.  Return the

# compiler output.

proc mips_preprocess { options code } {

    global tool

    set src dummy[pid].c

    set f [open $src "w"]

    puts $f $code

    close $f

    set output [${tool}_target_compile $src "" preprocess $options]

    file delete $src

    return $output

}

# Set the target board's command-line options to NEW_OPTIONS, storing the

# old values in UPVAR.

proc mips_push_test_options { upvar new_options } {

    upvar $upvar var

    global board_info

    array unset var

    set var(name) board_info([target_info name],multilib_flags)

    if { [info exists $var(name)] } {

        set var(old_options) [set $var(name)]

        set $var(name) [join $new_options " "]

    }

}

# Undo the effects of [mips_push_test_options UPVAR ...]

proc mips_pop_test_options { upvar } {

    upvar $upvar var

    global board_info

    if { [info exists var(old_options)] } {

        set $var(name) $var(old_options)

    }

}

# Return property PROP for architecture option ARCH (which belongs to

# the "arch" group in mips_option_groups).  See the comment at the

# top of the file for the valid property names.

#

# Cache the results in mips_arch_info (which can be reused between test

# variants).

proc mips_arch_info { arch prop } {

    global mips_arch_info

    global board_info

    set arch [mips_canonicalize_option $arch]

    if { ![info exists mips_arch_info($arch,$prop)] } {

        mips_push_test_options saved_options {}

        set output [mips_preprocess [list "additional_flags=$arch -mabi=32"] {

            int isa = __mips;

            #ifdef __mips_isa_rev

            int isa_rev = __mips_isa_rev;

            #else

            int isa_rev = 0;

            #endif

        }]

        foreach lhs { isa isa_rev } {

            regsub ".*$lhs = (\[^;\]*).*" $output {\1} rhs

            verbose -log "Architecture $arch has $lhs $rhs"

            set mips_arch_info($arch,$lhs) $rhs

        }

        mips_pop_test_options saved_options

    }

    return $mips_arch_info($arch,$prop)

}

# Return the option group associated with OPTION, or "" if none.

proc mips_option_maybe_group { option } {

    global mips_option_groups

    foreach { group regexp } $mips_option_groups {

        if { [regexp -- "^($regexp)\$" $option] } {

            return $group

        }

    }

    return ""

}

# Return the option group associated with OPTION.  Raise an error if

# there is none.

proc mips_option_group { option } {

    set group [mips_option_maybe_group $option]

    if { [string equal $group ""] } {

        error "Unrecognised option: $option"

    }

    return $group

}

# Return the option for option group GROUP, or "" if no option in that

# group has been chosen.  UPSTATUS describes the option status.

proc mips_option { upstatus group } {

    upvar $upstatus status

    return $status(option,$group)

}

# If the base options for this test run include an option in group GROUP,

# return that option, otherwise return "".

proc mips_original_option { group } {

    global mips_base_options

    return [mips_option mips_base_options $group]

}

# Return true if the test described by UPSTATUS requires a specific

# option in group GROUP.  UPSTATUS describes the option status.

proc mips_test_option_p { upstatus group } {

    upvar $upstatus status

    return $status(test_option_p,$group)

}

# If the test described by UPSTATUS requires a particular option in group

# GROUP, return that option, otherwise return "".

proc mips_test_option { upstatus group } {

    upvar $upstatus status

    if { [mips_test_option_p status $group] } {

        return [mips_option status $group]

    } else {

        return ""

    }

}

# Return true if the options described by UPSTATUS include OPTION.

proc mips_have_option_p { upstatus option } {

    upvar $upstatus status

    return [mips_same_option_p \

                [mips_option status [mips_option_group $option]] \

                $option]

}

# Return true if the test described by UPSTATUS requires option OPTION.

proc mips_have_test_option_p { upstatus option } {

    upvar $upstatus status

    set group [mips_option_group $option]

    return [mips_same_option_p [mips_test_option status $group] $option]

}

# If the test described by UPSTATUS does not specify an option in

# OPTION's group, act as though it had specified OPTION.

#

# The first optional argument indicates whether the option should be

# treated as though it were wrapped in parentheses; see the comment at

# the top of the file for details about this convention.  The default is 0.

proc mips_make_test_option { upstatus option args } {

    upvar $upstatus status

    set group [mips_option_group $option]

    if { ![mips_test_option_p status $group] } {

        set status(option,$group) $option

        set status(test_option_p,$group) 1

        if { [llength $args] == 0 || ![lindex $args 0] } {

            set status(explicit_p,$group) 1

        }

    }

}

# If the test described by UPSTATUS requires option FROM, assume that

# it implicitly requires option TO.

proc mips_option_dependency { upstatus from to } {

    upvar $upstatus status

    if { [mips_have_test_option_p status $from] } {

        mips_make_test_option status $to

    }

}

# Return true if the given arch-group option specifies a 32-bit ISA.

proc mips_32bit_arch_p { option } {

    set isa [mips_arch_info $option isa]

    return [expr { $isa < 3 || $isa == 32 }]

}

# Return true if the given arch-group option specifies a 64-bit ISA.

proc mips_64bit_arch_p { option } {

    return [expr { ![mips_32bit_arch_p $option] }]

}

# Return true if the given abi-group option implicitly requires -mgp32.

proc mips_32bit_abi_p { option } {

    switch -glob -- $option {

        -mabi=32 {

            return 1

        }

    }

    return 0

}

# Return true if the given abi-group option implicitly requires -mgp64.

proc mips_64bit_abi_p { option } {

    switch -glob -- $option {

        -mabi=o64 -

        -mabi=n32 -

        -mabi=64 {

            return 1

        }

    }

    return 0

}

# Check whether the current target supports all the options that the

# current test requires.  Return "" if so, otherwise return one of

# the incompatible options.  UPSTATUS describes the option status.

proc mips_first_unsupported_option { upstatus } {

    global mips_option_tests

    upvar $upstatus status

    foreach { option code } [array get mips_option_tests] {

        if { [mips_have_test_option_p status $option] } {

            regsub -all "\n" $code "\\n\\\n" asm

            # Use check_runtime from target-supports.exp, which caches

            # the result for us.

            if { ![check_runtime mips_option_$option [subst {

                __attribute__((nomips16)) int

                main (void)

                {

                    asm (".set push\

                    $asm\

                    .set pop");

                    return 0;

                }

            }]] } {

                return $option

            }

        }

    }

    return ""

}

# Initialize this testsuite for a new test variant.

proc mips-dg-init {} {

    # Invariant information.

    global mips_option_groups

    # Internally-generated information about this run.

    global mips_base_options

    global mips_extra_options

    # Override dg-options with our mips-dg-options routine.

    rename dg-options mips-old-dg-options

    rename mips-dg-options dg-options

    # Start with a fresh option status.

    array unset mips_base_options

    foreach { group regexp } $mips_option_groups {

        set mips_base_options(option,$group) ""

        set mips_base_options(explicit_p,$group) 0

        set mips_base_options(test_option_p,$group) 0

    }

    # Use preprocessor macros to work out as many implicit options as we can.

    set output [mips_preprocess "" {

        const char *options[] = {

            #if !defined _MIPS_SIM

            "-mabi=eabi",

            #elif _MIPS_SIM==_ABIO32

            "-mabi=32",

            #elif _MIPS_SIM==_ABIO64

            "-mabi=o64",

            #elif _MIPS_SIM==_ABIN32

            "-mabi=n32",

            #else

            "-mabi=64",

            #endif

            "-march=" _MIPS_ARCH,

            #ifdef _MIPSEB

            "-EB",

            #else

            "-EL",

            #endif

            #ifdef __mips_hard_float

            "-mhard-float",

            #else

            "-msoft-float",

            #endif

            #if __mips_fpr == 64

            "-mfp64",

            #else

            "-mfp32",

            #endif

            #ifdef __mips64

            "-mgp64",

            #else

            "-mgp32",

            #endif

            #if _MIPS_SZLONG == 64

            "-mlong64",

            #else

            "-mlong32",

            #endif

            #ifdef __mips16

            "-mips16",

            #else

            "-mno-mips16",

            #endif

            #ifdef __mips3d

            "-mips3d",

            #else

            "-mno-mips3d",

            #endif

            #ifdef __mips_paired_single_float

            "-mpaired-single",

            #else

            "-mno-paired-single",

            #endif

            #if __mips_abicalls

            "-mabicalls",

            #else

            "-mno-abicalls",

            #endif

            #if __mips_dsp_rev >= 2

            "-mdspr2",

            #else

            "-mno-dspr2",

            #endif

            #if __mips_dsp_rev >= 1

            "-mdsp",

            #else

            "-mno-dsp",

            #endif

            #ifndef __PIC__

            "addressing=absolute",

            #endif

            #ifdef __mips_smartmips

            "-msmartmips",

            #else

            "-mno-smartmips",

            #endif

        };

    }]

    foreach line [split $output "\r\n"] {

        # Poor man's string concatenation.

        regsub -all {" "} $line "" line

        if { [regexp {"(.*)",} $line dummy option] } {

            set group [mips_option_group $option]

            set mips_base_options(option,$group) $option

        }

    }

    # Process the target's multilib options, saving any unrecognized

    # ones in mips_extra_options.

    set mips_extra_options {}

    foreach option [split [board_info target multilib_flags]] {

        set group [mips_option_maybe_group $option]

        if { ![string equal $group ""] } {

            set mips_base_options(option,$group) $option

            set mips_base_options(explicit_p,$group) 1

        } else {

            lappend mips_extra_options $option

        }

    }

}

# Finish a test run started by mips-dg-init.

proc mips-dg-finish {} {

    rename dg-options mips-dg-options

    rename mips-old-dg-options dg-options

}

# Override dg-options so that we can do some MIPS-specific processing.

# All options used in this testsuite must appear in mips_option_groups.

#

# Test options override multilib options.  Certain test options can

# also imply other test options, which also override multilib options.

# These dependencies are ordered as follows:

#

#          START                        END

#            |                           |

#         -mips16                     -mno-mips16

#            |                           |

#         -mips3d                     -mno-mips3d

#            |                           |

#         -mpaired-single             -mno-paired-single

#            |                           |

#         -mfp64                      -mfp32

#            |                           |

#         -mhard-float                -msoft-float

#            |                           |

#         -mno-sym32                  -msym32

#            |                           |

#         -mrelax-pic-calls           -mno-relax-pic-calls

#            |                           |

#         -fpic                       -fno-pic

#            |                           |

#         -mshared                    -mno-shared

#            |                           |

#         -mno-plt                    -mplt

#            |                           |

#         addressing=unknown          addressing=absolute

#            |                           |

#         -mabicalls                  -mno-abicalls

#            |                           |

#         -G0                         

#            |                           |

#                        -mr10k-cache-barrier=none

#            |                           |

#         -mfix-r10000                -mno-fix-r10000

#            |                           |

#         -mbranch-likely             -mno-branch-likely

#            |                           |

#         -msmartmips                 -mno-smartmips

#            |                           |

#         -mno-gpopt                  -mgpopt

#            |                           |

#         -mexplicit-relocs           -mno-explicit-relocs

#            |                           |

#            +-- gp, abi & arch ---------+

#

# For these purposes, the "gp", "abi" & "arch" option groups are treated

# as a single node.

proc mips-dg-options { args } {

    # dg.exp variables.

    upvar dg-extra-tool-flags extra_tool_flags

    upvar dg-do-what do_what

    # Invariant information.

    global mips_option_groups

    global mips_abi_groups

    # Information about this run.

    global mips_base_options

    # Start out with the default option state.

    array set options [array get mips_base_options]

    # Record the options that this test explicitly needs.

    foreach option [lindex $args 1] {

        set all_but_p [regexp {^\((.*)\)$} $option dummy option]

        set group [mips_option_group $option]

        if { [mips_test_option_p options $group] } {

            set old [mips_option options $group]

            error "Inconsistent $group option: $old vs. $option"

        } else {

            mips_make_test_option options $option $all_but_p

        }

    }

    # Handle dependencies between options on the left of the

    # dependency diagram.

    mips_option_dependency options "-mips3d" "-mpaired-single"

    mips_option_dependency options "-mpaired-single" "-mfp64"

    mips_option_dependency options "-mfp64" "-mhard-float"

    mips_option_dependency options "-mrelax-pic-calls" "-mno-plt"

    mips_option_dependency options "-mrelax-pic-calls" "-mabicalls"

    mips_option_dependency options "-mrelax-pic-calls" "-mexplicit-relocs"

    mips_option_dependency options "-fpic" "-mshared"

    mips_option_dependency options "-mshared" "-mno-plt"

    mips_option_dependency options "-mno-plt" "addressing=unknown"

    mips_option_dependency options "-mabicalls" "-G0"

    mips_option_dependency options "-mno-gpopt" "-mexplicit-relocs"

    # Work out information about the current ABI.

    set abi_test_option_p [mips_test_option_p options abi]

    set abi [mips_option options abi]

    set eabi_p [mips_same_option_p $abi "-mabi=eabi"]

    # If the test forces a particular ABI, set the register size

    # accordingly.

    if { $abi_test_option_p } {

        if { [mips_32bit_abi_p $abi] } {

            mips_make_test_option options "-mgp32"

        } elseif { [mips_64bit_abi_p $abi] } {

            mips_make_test_option options "-mgp64"

        }

    }

    # See whether forbid_cpu forces us to choose a new architecture.

    set arch [mips_option mips_base_options arch]

    set force_generic_isa_p [expr {

        [regexp "forbid_cpu=(.*)" [mips_option options forbid_cpu] dummy spec]

        && [regexp -- "^-march=$spec\$" $arch]

    }]

    # Interpret the special "isa" and "isa_rev" options.  If we have

    # a choice of a 32-bit or a 64-bit architecture, prefer to keep

    # the -mgp setting the same.

    set spec [mips_option options arch]

    if { [regexp {^[^-]} $spec] } {

        if { [string equal $spec "isa=loongson"] } {

            if { ![regexp {^-march=loongson} $arch] } {

                set arch "-march=loongson2f"

            }

        } else {

            if { ![regexp {^(isa(?:|_rev))(=|<=|>=)([0-9]*)$} \

                       $spec dummy prop relation value nocpus] } {

                error "Unrecognized isa specification: $spec"

            }

            set current [mips_arch_info $arch $prop]

            if { $force_generic_isa_p

                 || ($current < $value && ![string equal $relation "<="])

                 || ($current > $value && ![string equal $relation ">="])

                 || ([mips_have_test_option_p options "-mgp64"]

                     && [mips_32bit_arch_p $arch]) } {

                # The current setting is out of range; it cannot

                # possibly be used.  Find a replacement that can.

                if { [string equal $prop "isa"] } {

                    set arch "-mips$value"

                } elseif { $value == 0 } {

                    set arch "-mips4"

                } else {

                    if { [mips_have_option_p options "-mgp32"] } {

                        set arch "-mips32"

                    } else {

                        set arch "-mips64"

                    }

                    if { $value > 1 } {

                        append arch "r$value"

                    }

                }

            }

        }

        set options(option,arch) $arch

    }

    # Work out information about the current architecture.

    set arch_test_option_p [mips_test_option_p options arch]

    set arch [mips_option options arch]

    set isa [mips_arch_info $arch isa]

    set isa_rev [mips_arch_info $arch isa_rev]

    # If the test forces a 32-bit architecture, force -mgp32.

    # Force the current -mgp setting otherwise; if we don't,

    # some configurations would make a 64-bit architecture

    # imply -mgp64.

    if { $arch_test_option_p } {

        if { [mips_32bit_arch_p $arch] } {

            mips_make_test_option options "-mgp32"

        } else {

            mips_make_test_option options [mips_option options gp]

        }

    }

    # We've now fixed the GP register size.  Make it easily available.

    set gp_size [expr { [mips_have_option_p options "-mgp32"] ? 32 : 64 }]

    # Handle dependencies between the pre-arch options and the arch option.

    # This should mirror the arch and post-arch code below.

    if { !$arch_test_option_p } {

        # We need a revision 2 or better ISA for:

        #

        #   - the combination of -mgp32 -mfp64