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Elixir Cross Referencer

# Copyright 2013-2020 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/>.
load_lib dwarf.exp

# This test can only be run on targets which support DWARF-2 and use gas.
if {![dwarf2_support]} {
    return 0
}

standard_testfile .c entry-values-dw.S

if  {[gdb_compile ${srcdir}/${subdir}/${srcfile} ${binfile}1.o \
	  object {nodebug}] != ""} {
    return -1
}

if  {[gdb_compile [list ${binfile}1.o] \
	  "${binfile}1" executable {}] != ""} {
    return -1
}

# Start GDB and load executable file, compute the offset of the
# instruction in bar returned from foo.  It is needed in the Dwarf
# Assembler.

gdb_exit
gdb_start
gdb_reinitialize_dir $srcdir/$subdir
gdb_load ${binfile}1

set returned_from_foo ""

if { [istarget "arm*-*-*"] || [istarget "aarch64*-*-*"] } {
    set call_insn "bl"
} elseif { [istarget "s390*-*-*"] } {
    set call_insn "brasl"
} elseif { [istarget "powerpc*-*-*"] } {
    set call_insn "bl"
} elseif { [istarget "mips*-*-*"] } {
    # Skip the delay slot after the instruction used to make a call
    # (which can be a jump or a branch) if it has one.
    #
    #  JUMP (or BRANCH) foo
    #  insn1
    #  insn2
    #
    # Most MIPS instructions used to make calls have a delay slot.
    # These include JAL, JALS, JALX, JALR, JALRS, BAL and BALS.
    # In this case the program continues from `insn2' when `foo'
    # returns.  The only exception is JALRC, in which case execution
    # resumes from `insn1' instead.
    set call_insn {jalrc|[jb]al[sxr]*[ \t][^\r\n]+\r\n}
} else {
    set call_insn "call"
}

# Calculate the offset of the instruction in bar returned from foo.
set test "disassemble bar"
gdb_test_multiple $test $test {
    -re ".*$hex <\\+$decimal>:\[ \t\]+\\y$call_insn\\y\[^\r\n\]+\r\n\[ \]+$hex <\\+($decimal)>:.*$gdb_prompt $" {
	set returned_from_foo $expect_out(1,string)
    }
    -re ".*$gdb_prompt $" {
	fail $test
    }
}

if { [string equal $returned_from_foo ""] } {
    fail "find the call or branch instruction offset in bar"
    # The following test makes no sense if the offset is unknown.  We need
    # to update the pattern above to match call or branch instruction for
    # the target architecture.
    return -1
}

gdb_exit

# Make some DWARF for the test.
set asm_file [standard_output_file $srcfile2]
Dwarf::assemble $asm_file {
    declare_labels int_label foo_label
    global returned_from_foo
    global srcdir subdir srcfile

    set bar_result [function_range bar ${srcdir}/${subdir}/${srcfile}]
    set bar_start [lindex $bar_result 0]
    set bar_length [lindex $bar_result 1]

    cu {} {
	compile_unit {{language @DW_LANG_C}} {
	    int_label: base_type {
		{name int}
		{encoding @DW_ATE_signed}
		{byte_size 4 DW_FORM_sdata}
	    }

	    foo_label: subprogram {
		{decl_file 0 udata}
		{MACRO_AT_func { foo }}
	    } {
		formal_parameter {
		    {type :$int_label}
		    {name i}
		    {location {DW_OP_reg0} SPECIAL_expr}
		}
		formal_parameter {
		    {type :$int_label}
		    {name j}
		    {location {DW_OP_reg1} SPECIAL_expr}
		}
	    }

	    subprogram {
		{name bar}
		{decl_file 0 udata}
		{low_pc $bar_start addr}
		{high_pc "$bar_start + $bar_length" addr}
		{GNU_all_call_sites 1 sdata}
	    } {
		formal_parameter {
		    {type :$int_label}
		    {name i}
		}

		GNU_call_site {
		    {low_pc "$bar_start + $returned_from_foo" addr}
		    {abstract_origin :$foo_label}
		} {
		    # Faked entry values are reference to variables 'global1'
		    # and 'global2' and faked locations are register 0 and
		    # register 1.
		    GNU_call_site_parameter {
			{location {DW_OP_reg0} SPECIAL_expr}
			{GNU_call_site_value {
			    addr global1
			    deref_size 4
			} SPECIAL_expr}
		    }
		    GNU_call_site_parameter {
			{location {DW_OP_reg1} SPECIAL_expr}
			{GNU_call_site_value {
			    addr global2
			    deref_size 4
			} SPECIAL_expr}
		    }
		}
	    }
	}
    }
}

if  {[gdb_compile $asm_file ${binfile}2.o object {nodebug}] != ""} {
    return -1
}

if  {[gdb_compile [list ${binfile}1.o ${binfile}2.o] \
	  "${binfile}" executable {}] != ""} {
    return -1
}

clean_restart ${testfile}

if ![runto_main] {
    fail "can't run to main"
    return -1
}

gdb_breakpoint "foo"

gdb_continue_to_breakpoint "foo"

gdb_test_no_output "set print entry-values both"

gdb_test_sequence "bt" "bt (1)" {
    "\[\r\n\]#0 .* foo \\(i=[-]?[0-9]+, i@entry=2, j=[-]?[0-9]+, j@entry=3\\)"
    "\[\r\n\]#1 .* bar \\(i=<optimized out>, i@entry=<optimized out>\\)"
    "\[\r\n\]#2 .* \.?main \\(\\)"
}

# Update global variables 'global1' and 'global2' and test that the
# entry values are updated too.

gdb_test_no_output "set var *(int *) &global1=10"
gdb_test_no_output "set var *(int *) &global2=11"

gdb_test_sequence "bt" "bt (2)" {
    "\[\r\n\]#0 .* foo \\(i=[-]?[0-9]+, i@entry=10, j=[-]?[0-9]+, j@entry=11\\)"
    "\[\r\n\]#1 .* bar \\(i=<optimized out>, i@entry=<optimized out>\\)"
    "\[\r\n\]#2 .* \.?main \\(\\)"
}

# Restart GDB and trace.

clean_restart $binfile

load_lib "trace-support.exp"

if ![runto_main] {
    fail "can't run to main to check for trace support"
    return -1
}

if ![gdb_target_supports_trace] {
    unsupported "target does not support trace"
    return -1
}

gdb_test "trace foo" "Tracepoint $decimal at .*"

# Collect arguments i and j.  Collect 'global1' which is entry value
# of argument i.  Don't collect 'global2' to test the entry value of
# argument j.

gdb_trace_setactions "set action for tracepoint 1" "" \
    "collect i, j, (int) global1, \(\*\(void \*\*\) \(\$$spreg\)\) @ 128" "^$"

gdb_test_no_output "tstart"

gdb_breakpoint "end"
gdb_continue_to_breakpoint "end"

gdb_test_no_output "tstop"

gdb_test "tfind" "Found trace frame 0, .*" "tfind start"

# Since 'global2' is not collected, j@entry is expected to be 'unavailable'.
gdb_test "bt 1" "#0 .* foo \\(i=\[-\]?$decimal, i@entry=2, j=\[-\]?$decimal, j@entry=<unavailable>\\).*"

# Test that unavailable "j@entry" is not shown when command option
# --skip-unavailable is used.
gdb_test "interpreter-exec mi \"-stack-list-arguments --skip-unavailable --simple-values\"" \
    "\r\n\\^done,stack-args=\\\[frame={level=\"0\",args=\\\[{name=\"i\",type=\"int\",value=\".*\"},{name=\"i@entry\",type=\"int\",value=\"2\"},{name=\"j\",type=\"int\",value=\".*\"}\\\]},frame=.*\\\].*"

gdb_test "tfind" "Target failed to find requested trace frame\..*"