gdb/testsuite/gdb.base/dcache-line-read-error.exp

# Copyright 2014-2021 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 this program.  If not, see <http://www.gnu.org/licenses/>.

# Test that dcache behaves correctly when reading a cache line fails.

standard_testfile

if { [prepare_for_testing "failed to prepare" ${testfile}] } {
    return -1
}

if ![runto breakpt] {
    return -1
}

# Issue the "delete mem" command.  This makes GDB ignore the
# target-provided list, if any.

proc delete_mem {} {
    global gdb_prompt

    set test "delete mem"
    gdb_test_multiple $test $test {
	-re "Delete all memory regions.*y or n.*$" {
	    send_gdb "y\n"
	    exp_continue
	}
	-re "$gdb_prompt $" {
	    pass $test
	}
    }
}

# Make the dcache line size bigger than the pagesize.
set pagesize [get_integer_valueof "pg_size" -1]
set linesize [expr $pagesize * 2]

gdb_test_no_output "set dcache line-size $linesize" \
    "set dcache line size to twice the pagesize"

gdb_test "info dcache" \
    "Dcache 4096 lines of $linesize bytes each.\r\nNo data cache available."

# Make sure dcache doesn't automatically skip unmapped regions.
delete_mem

gdb_test "info mem" \
    "Using user-defined memory regions.\r\nThere are no memory regions defined\."

# Given the line size is bigger than the page size, we have
# alternating mapped and unmapped pages, these make dcache fail to
# fill in the cache line.  GDB used to have a bug where that failure
# would end up as user-visible error.  The range being disassembled is
# wholly available, so GDB should succeed.
gdb_test "disassemble first_mapped_page, +10" "End of assembler dump\."
gdb_test "disassemble last_mapped_page, +10" "End of assembler dump\."