gdb/testsuite/gdb.base/watchpoint-reuse-slot.exp - binutils-gdb - Git at Google

 # Copyright 2014-2020 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 alternating between watchpoint types, watching a sliding window
 # of addresses (thus alternating between aligned and unaligned
 # addresses).  Only a single watchpoint exists at any given time.  On
 # targets that only update the debug registers on resume, this
 # stresses the debug register setup code, both in GDB and in the
 # target/kernel as one watchpoint replaces the other in a single
 # operation.  (Note that we don't have any of these watchpoints
 # trigger.)

 standard_testfile

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

 if ![runto_main] then {
     fail "can't run to main"
     return 0
 }

 # The line we'll be stepping.
 set srcline [gdb_get_line_number "stepi line"]

 # The address the program is stopped at currently.
 set cur_addr ""

 # Get the current PC.

 proc get_pc {} {
     global hex gdb_prompt

     set addr ""
     set test "get PC"
     gdb_test_multiple "p /x \$pc" "$test" {
 	-re " = ($hex).*$gdb_prompt $" {
 	    set addr $expect_out(1,string)
 	    pass "$test"
 	}
     }

     return $addr
 }


 # Issue a stepi, and make sure the program advanced past the current
 # instruction (stored in the CUR_ADDR global).

 proc stepi {} {
     global hex gdb_prompt cur_addr

     set srcline "  for (i = 0; i < 100000; i++); /* stepi line */"
     set test "stepi advanced"
     gdb_test_multiple "stepi" $test {
 	-re "($hex).*[string_to_regexp $srcline]\r\n$gdb_prompt $" {
 	    set addr $expect_out(1,string)
 	    if {$addr != $cur_addr} {
 		pass $test
 	    } else {
 		fail $test
 	    }
 	    set cur_addr addr
 	}
     }
 }

 gdb_breakpoint $srcline
 gdb_continue_to_breakpoint "stepi line"
 set cur_addr [get_pc]

 # The test tries various sequences of different types of watchpoints.
 # Probe for support first.
 proc build_cmds_list {} {
     global gdb_prompt

     # So we get an immediate warning/error if the target doesn't support a
     # given watchpoint type.
     gdb_test_no_output "set breakpoint always-inserted on" \
 	"Set breakpoints always inserted while building cmds list"

     # The list of supported commands.  Below we'll probe for support and
     # add elements to this list.
     set cmds {}

     foreach cmd {"watch" "awatch" "rwatch"} {
 	set test $cmd
 	gdb_test_multiple "$cmd buf.byte\[0\]" $test {
 	    -re "You may have requested too many.*$gdb_prompt $" {
 		unsupported $test
 	    }
 	    -re "Target does not support.*$gdb_prompt $" {
 		unsupported $test
 	    }
 	    -re "Can't set read/access watchpoint when hardware watchpoints are disabled.*$gdb_prompt $" {
 		unsupported $test
 	    }
 	    -re "$gdb_prompt $" {
 		pass $test
 		lappend cmds $cmd
 	    }
 	}

 	delete_breakpoints
     }

     set test "hbreak"
     gdb_test_multiple "hbreak main" $test {
 	-re "You may have requested too many.*$gdb_prompt $" {
 	    unsupported $test
 	}
 	-re "No hardware breakpoint support.*$gdb_prompt $" {
 	    unsupported $test
 	}
 	-re "$gdb_prompt $" {
 	    pass $test
 	    lappend cmds "hbreak"
 	}
     }

     delete_breakpoints

     return $cmds
 }

 # Return true if the memory range [buf.byte + OFFSET, +WIDTH] can be
 # monitored by CMD, otherwise return false.

 proc valid_addr_p {cmd offset width} {

     if { [istarget "aarch64*-*-linux*"] } {
 	# The aarch64 Linux kernel port only accepts 4-byte aligned addresses
 	# for hardware breakpoints and 8-byte aligned addresses for hardware
 	# watchpoints.  However, both GDB and GDBserver support unaligned
 	# watchpoints by using more than one properly aligned watchpoint
 	# registers to represent the whole unaligned region.  Breakpoint
 	# addresses must still be aligned though.
 	if {$cmd == "hbreak" } {
 	    if { [expr ($offset) % 4] != 0 } {
 		return 0
 	    }
 	}
     } elseif { [istarget "arm*-*-linux*"] } {
 	if { $cmd == "hbreak" } {
 	    # Breakpoints must be of length 2 (thumb) or 4 (ARM) bytes.
 	    if { $width != 2 && $width != 4 } {
 		return 0
 	    }
 	} else {
 	    # Watchpoints can be of length 1, 2, 4 or 8 bytes.
 	    if { [expr $width % 2] != 0 } {
 		return 0
 	    }
 	}

 	if { [expr ($offset) % 8] == 0 && $width == 8 } {
 	    # If WIDTH is 8 byte, the address should be 8-byte aligned.
 	    return 1
 	} elseif { [expr ($offset) % 4] == 0 } {
 	    return 1
 	} elseif { [expr ($offset) % 4] == 2 && $width == 2 } {
 	    # Halfword watchpoints and breakpoints.
 	    return 1
 	} elseif { [expr ($offset) % 4] == 1 && $width == 1 && $cmd != "hbreak" } {
 	    # Single byte watchpoints.
 	    return 1
 	} else {
 	    return 0
 	}
     }

     return 1
 }

 # Watch WIDTH bytes at BASE + OFFSET.  CMD specifices the specific
 # type of watchpoint to use.  If CMD is "hbreak", WIDTH is ignored.
 # The HW_WP_P flag tells us if hardware watchpoints are enabled or
 # not.

 proc watch_command {cmd base offset width hw_wp_p} {
     global srcfile srcline hex

     if {$cmd == "hbreak"} {
 	set expr "*(buf.byte + $base + $offset)"
 	gdb_test "hbreak $expr" "Hardware assisted breakpoint \[0-9\]+ at $hex"
     } elseif {$cmd == "watch"} {
 	set expr "*(buf.byte + $base + $offset)@$width"

 	if { ! $hw_wp_p } {
 	    set wp_prefix "Watchpoint"
 	} else {
 	    set wp_prefix "Hardware watchpoint"
 	}

 	gdb_test "$cmd $expr" \
 	    "${wp_prefix} \[0-9\]+: [string_to_regexp $expr]"
     } elseif {$cmd == "awatch"} {
 	set expr "*(buf.byte + $base + $offset)@$width"
 	gdb_test "$cmd $expr" \
 	    "Hardware access \\(read/write\\) watchpoint \[0-9\]+: [string_to_regexp $expr]"
     } elseif {$cmd == "rwatch"} {
 	set expr "*(buf.byte + $base + $offset)@$width"
 	gdb_test "$cmd $expr" \
 	    "Hardware read watchpoint \[0-9\]+: [string_to_regexp $expr]"
     }
 }

 # Run the watchpoint tests (see the description at the top for details), the
 # HW_WP_P flag tells us if hardware watchpoints are enabled or not.
 proc run_watchpoints_tests {hw_wp_p} {

     set cmds [build_cmds_list]

     foreach always_inserted {"off" "on" } {
 	gdb_test_no_output "set breakpoint always-inserted $always_inserted"
 	foreach cmd1 $cmds {
 	    foreach cmd2 $cmds {
 		for {set width 1} {$width < 4} {incr width} {

 		    if {$cmd1 == "hbreak" && $cmd2 == "hbreak" \
 			    && $width > 1} {
 			# hbreak ignores WIDTH, no use testing more than
 			# once.
 			continue
 		    }

 		    for {set x 0} {$x < 4} {incr x} {

 			if { ![valid_addr_p $cmd1 $x $width]
 			     || ![valid_addr_p $cmd2 $x+1 $width] } {
 			    # Skip tests if requested address or length
 			    # of breakpoint or watchpoint don't meet
 			    # target or kernel requirements.
 			    continue
 			}

 			set prefix "always-inserted $always_inserted: "
 			append prefix "$cmd1 x $cmd2: "
 			with_test_prefix "$prefix: width $width, iter $x" {
 			    with_test_prefix "base + 0" {
 				watch_command $cmd1 $x 0 $width $hw_wp_p
 				stepi
 				gdb_test_no_output "delete \$bpnum"
 			    }
 			    with_test_prefix "base + 1" {
 				watch_command $cmd2 $x 1 $width $hw_wp_p
 				stepi
 				gdb_test_no_output "delete \$bpnum"
 			    }
 			}
 		    }
 		}
 	    }
 	}
     }
 }

 # Based on HW_WP_P set whether hardware watchpoints can be used or
 # not, then call RUN_WATCHPOINTS_TESTS.
 proc setup_and_run_watchpoints_tests { hw_wp_p } {
     if {$hw_wp_p} {
 	set prefix "hw-watch"
     } else {
 	set prefix "sw-watch"
     }

     with_test_prefix $prefix {
 	gdb_test_no_output "set can-use-hw-watchpoints ${hw_wp_p}"

 	run_watchpoints_tests $hw_wp_p
     }
 }

 # Run tests with hardware watchpoints disabled, then again with them
 # enabled (if this target supports hardware watchpoints).
 if { ![target_info exists gdb,no_hardware_watchpoints]} {
     # Run test with H/W enabled.
     setup_and_run_watchpoints_tests 1
 }

 # Run test with H/W disabled
 setup_and_run_watchpoints_tests 0
	# Copyright 2014-2020 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 alternating between watchpoint types, watching a sliding window
	# of addresses (thus alternating between aligned and unaligned
	# addresses). Only a single watchpoint exists at any given time. On
	# targets that only update the debug registers on resume, this
	# stresses the debug register setup code, both in GDB and in the
	# target/kernel as one watchpoint replaces the other in a single
	# operation. (Note that we don't have any of these watchpoints
	# trigger.)

	standard_testfile

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

	if ![runto_main] then {
	fail "can't run to main"
	return 0
	}

	# The line we'll be stepping.
	set srcline [gdb_get_line_number "stepi line"]

	# The address the program is stopped at currently.
	set cur_addr ""

	# Get the current PC.

	proc get_pc {} {
	global hex gdb_prompt

	set addr ""
	set test "get PC"
	gdb_test_multiple "p /x \$pc" "$test" {
	-re " = ($hex).*$gdb_prompt $" {
	set addr $expect_out(1,string)
	pass "$test"
	}
	}

	return $addr
	}


	# Issue a stepi, and make sure the program advanced past the current
	# instruction (stored in the CUR_ADDR global).

	proc stepi {} {
	global hex gdb_prompt cur_addr

	set srcline " for (i = 0; i < 100000; i++); /* stepi line */"
	set test "stepi advanced"
	gdb_test_multiple "stepi" $test {
	-re "($hex).*[string_to_regexp $srcline]\r\n$gdb_prompt $" {
	set addr $expect_out(1,string)
	if {$addr != $cur_addr} {
	pass $test
	} else {
	fail $test
	}
	set cur_addr addr
	}
	}
	}

	gdb_breakpoint $srcline
	gdb_continue_to_breakpoint "stepi line"
	set cur_addr [get_pc]

	# The test tries various sequences of different types of watchpoints.
	# Probe for support first.
	proc build_cmds_list {} {
	global gdb_prompt

	# So we get an immediate warning/error if the target doesn't support a
	# given watchpoint type.
	gdb_test_no_output "set breakpoint always-inserted on" \
	"Set breakpoints always inserted while building cmds list"

	# The list of supported commands. Below we'll probe for support and
	# add elements to this list.
	set cmds {}

	foreach cmd {"watch" "awatch" "rwatch"} {
	set test $cmd
	gdb_test_multiple "$cmd buf.byte\[0\]" $test {
	-re "You may have requested too many.*$gdb_prompt $" {
	unsupported $test
	}
	-re "Target does not support.*$gdb_prompt $" {
	unsupported $test
	}
	-re "Can't set read/access watchpoint when hardware watchpoints are disabled.*$gdb_prompt $" {
	unsupported $test
	}
	-re "$gdb_prompt $" {
	pass $test
	lappend cmds $cmd
	}
	}

	delete_breakpoints
	}

	set test "hbreak"
	gdb_test_multiple "hbreak main" $test {
	-re "You may have requested too many.*$gdb_prompt $" {
	unsupported $test
	}
	-re "No hardware breakpoint support.*$gdb_prompt $" {
	unsupported $test
	}
	-re "$gdb_prompt $" {
	pass $test
	lappend cmds "hbreak"
	}
	}

	delete_breakpoints

	return $cmds
	}

	# Return true if the memory range [buf.byte + OFFSET, +WIDTH] can be
	# monitored by CMD, otherwise return false.

	proc valid_addr_p {cmd offset width} {

	if { [istarget "aarch64--linux*"] } {
	# The aarch64 Linux kernel port only accepts 4-byte aligned addresses
	# for hardware breakpoints and 8-byte aligned addresses for hardware
	# watchpoints. However, both GDB and GDBserver support unaligned
	# watchpoints by using more than one properly aligned watchpoint
	# registers to represent the whole unaligned region. Breakpoint
	# addresses must still be aligned though.
	if {$cmd == "hbreak" } {
	if { [expr ($offset) % 4] != 0 } {
	return 0
	}
	}
	} elseif { [istarget "arm--linux*"] } {
	if { $cmd == "hbreak" } {
	# Breakpoints must be of length 2 (thumb) or 4 (ARM) bytes.
	if { $width != 2 && $width != 4 } {
	return 0
	}
	} else {
	# Watchpoints can be of length 1, 2, 4 or 8 bytes.
	if { [expr $width % 2] != 0 } {
	return 0
	}
	}

	if { [expr ($offset) % 8] == 0 && $width == 8 } {
	# If WIDTH is 8 byte, the address should be 8-byte aligned.
	return 1
	} elseif { [expr ($offset) % 4] == 0 } {
	return 1
	} elseif { [expr ($offset) % 4] == 2 && $width == 2 } {
	# Halfword watchpoints and breakpoints.
	return 1
	} elseif { [expr ($offset) % 4] == 1 && $width == 1 && $cmd != "hbreak" } {
	# Single byte watchpoints.
	return 1
	} else {
	return 0
	}
	}

	return 1
	}

	# Watch WIDTH bytes at BASE + OFFSET. CMD specifices the specific
	# type of watchpoint to use. If CMD is "hbreak", WIDTH is ignored.
	# The HW_WP_P flag tells us if hardware watchpoints are enabled or
	# not.

	proc watch_command {cmd base offset width hw_wp_p} {
	global srcfile srcline hex

	if {$cmd == "hbreak"} {
	set expr "*(buf.byte + $base + $offset)"
	gdb_test "hbreak $expr" "Hardware assisted breakpoint \[0-9\]+ at $hex"
	} elseif {$cmd == "watch"} {
	set expr "*(buf.byte + $base + $offset)@$width"

	if { ! $hw_wp_p } {
	set wp_prefix "Watchpoint"
	} else {
	set wp_prefix "Hardware watchpoint"
	}

	gdb_test "$cmd $expr" \
	"${wp_prefix} \[0-9\]+: [string_to_regexp $expr]"
	} elseif {$cmd == "awatch"} {
	set expr "*(buf.byte + $base + $offset)@$width"
	gdb_test "$cmd $expr" \
	"Hardware access \\(read/write\\) watchpoint \[0-9\]+: [string_to_regexp $expr]"
	} elseif {$cmd == "rwatch"} {
	set expr "*(buf.byte + $base + $offset)@$width"
	gdb_test "$cmd $expr" \
	"Hardware read watchpoint \[0-9\]+: [string_to_regexp $expr]"
	}
	}

	# Run the watchpoint tests (see the description at the top for details), the
	# HW_WP_P flag tells us if hardware watchpoints are enabled or not.
	proc run_watchpoints_tests {hw_wp_p} {

	set cmds [build_cmds_list]

	foreach always_inserted {"off" "on" } {
	gdb_test_no_output "set breakpoint always-inserted $always_inserted"
	foreach cmd1 $cmds {
	foreach cmd2 $cmds {
	for {set width 1} {$width < 4} {incr width} {

	if {$cmd1 == "hbreak" && $cmd2 == "hbreak" \
	&& $width > 1} {
	# hbreak ignores WIDTH, no use testing more than
	# once.
	continue
	}

	for {set x 0} {$x < 4} {incr x} {

	if { ![valid_addr_p $cmd1 $x $width]
	\|\| ![valid_addr_p $cmd2 $x+1 $width] } {
	# Skip tests if requested address or length
	# of breakpoint or watchpoint don't meet
	# target or kernel requirements.
	continue
	}

	set prefix "always-inserted $always_inserted: "
	append prefix "$cmd1 x $cmd2: "
	with_test_prefix "$prefix: width $width, iter $x" {
	with_test_prefix "base + 0" {
	watch_command $cmd1 $x 0 $width $hw_wp_p
	stepi
	gdb_test_no_output "delete \$bpnum"
	}
	with_test_prefix "base + 1" {
	watch_command $cmd2 $x 1 $width $hw_wp_p
	stepi
	gdb_test_no_output "delete \$bpnum"
	}
	}
	}
	}
	}
	}
	}
	}

	# Based on HW_WP_P set whether hardware watchpoints can be used or
	# not, then call RUN_WATCHPOINTS_TESTS.
	proc setup_and_run_watchpoints_tests { hw_wp_p } {
	if {$hw_wp_p} {
	set prefix "hw-watch"
	} else {
	set prefix "sw-watch"
	}

	with_test_prefix $prefix {
	gdb_test_no_output "set can-use-hw-watchpoints ${hw_wp_p}"

	run_watchpoints_tests $hw_wp_p
	}
	}

	# Run tests with hardware watchpoints disabled, then again with them
	# enabled (if this target supports hardware watchpoints).
	if { ![target_info exists gdb,no_hardware_watchpoints]} {
	# Run test with H/W enabled.
	setup_and_run_watchpoints_tests 1
	}

	# Run test with H/W disabled
	setup_and_run_watchpoints_tests 0