gdb/testsuite/gdb.dwarf2/dw2-llvm-offset.exp

# Copyright 2017-2021 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 DWARF operation that allow adding byte and bit offset to any
# location description.
#
# In particular, the test uses memory and register location
# descriptions (both as standalone and parts of the composite
# location), and applies different byte and bit offsets to them.

load_lib dwarf.exp

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

# Choose suitable integer registers for the test.

set dwarf_regnum 0

if { [is_aarch64_target] } {
    set regname x0
} elseif { [is_aarch32_target]
	   || [istarget "s390*-*-*" ]
	   || [istarget "powerpc*-*-*"]
	   || [istarget "rs6000*-*-aix*"] } {
    set regname r0
} elseif { [is_x86_like_target] } {
    set regname eax
} elseif { [is_amd64_regs_target] } {
    set regname rax
} else {
    verbose "Skipping ${gdb_test_file_name}."
    return
}

standard_testfile var-access.c ${gdb_test_file_name}-dw.S

# Make some DWARF for the test.

set asm_file [standard_output_file $srcfile2]
Dwarf::assemble $asm_file {
    global dwarf_regnum regname srcdir subdir srcfile
    set buf_var [gdb_target_symbol buf]

    set main_result [function_range main ${srcdir}/${subdir}/${srcfile}]
    set main_start [lindex $main_result 0]
    set main_length [lindex $main_result 1]

    cu {} {
	DW_TAG_compile_unit {
	    {DW_AT_name var-access.c}
	    {DW_AT_comp_dir /tmp}
	} {
	    declare_labels char_type_label int_type_label
	    declare_labels array_size_4_type_label array_size_8_type_label

	    # define char type.
	    char_type_label: DW_TAG_base_type {
		{DW_AT_name "char"}
		{DW_AT_encoding @DW_ATE_signed}
		{DW_AT_byte_size 1 DW_FORM_sdata}
	    }

	    # define int type.
	    int_type_label: DW_TAG_base_type {
		{DW_AT_name "int"}
		{DW_AT_encoding @DW_ATE_signed}
		{DW_AT_byte_size 4 DW_FORM_sdata}
	    }

	    # define 4 byte size array type.
	    array_size_4_type_label: DW_TAG_array_type {
		{DW_AT_type :$char_type_label}
	    } {
		DW_TAG_subrange_type {
		    {DW_AT_type :$int_type_label}
		    {DW_AT_upper_bound 3 DW_FORM_udata}
		}
	    }

	    # define 8 byte size array type.
	    array_size_8_type_label: DW_TAG_array_type {
		{DW_AT_type :$char_type_label}
	    } {
		DW_TAG_subrange_type {
		    {DW_AT_type :$int_type_label}
		    {DW_AT_upper_bound 7 DW_FORM_udata}
		}
	    }

	    DW_TAG_subprogram {
		{DW_AT_name main}
		{DW_AT_low_pc $main_start addr}
		{DW_AT_high_pc $main_length data8}
	    } {
		# define original buf variable.
		DW_TAG_variable {
		    {DW_AT_name buf}
		    {DW_AT_type :$array_size_4_type_label}
		    {DW_AT_location {
			DW_OP_addr $buf_var
		    } SPECIAL_expr}
		}

		# defined a variable located in
		# a third byte of the buf variable.
		DW_TAG_variable {
		    {DW_AT_name buf_byte_3}
		    {DW_AT_type :$char_type_label}
		    {DW_AT_location {
			DW_OP_addr $buf_var
			DW_OP_LLVM_offset_constu 2
		    } SPECIAL_expr}
		    {external 1 flag}
		}

		# defined a variable located in a second byte
		# of the buf variable with a bit offset of one.
		DW_TAG_variable {
		    {DW_AT_name buf_byte_2_bit_1}
		    {DW_AT_type :$char_type_label}
		    {DW_AT_location {
			DW_OP_addr $buf_var
			DW_OP_lit9
			DW_OP_LLVM_bit_offset
		    } SPECIAL_expr}
		    {external 1 flag}
		}

		# defined a variable located in a
		# third byte of the REGNAME register.
		DW_TAG_variable {
		    {DW_AT_name reg_byte_3}
		    {DW_AT_type :$char_type_label}
		    {DW_AT_location {
			DW_OP_regx $dwarf_regnum
			DW_OP_lit2
			DW_OP_LLVM_offset
		    } SPECIAL_expr}
		    {external 1 flag}
		}

		# defined a variable located in a second byte of
		# the REGNAME register with a bit offset of one.
		DW_TAG_variable {
		    {DW_AT_name reg_byte_2_bit_1}
		    {DW_AT_type :$char_type_label}
		    {DW_AT_location {
			DW_OP_regx $dwarf_regnum
			DW_OP_lit1
			DW_OP_LLVM_offset
			DW_OP_lit1
			DW_OP_LLVM_bit_offset
		    } SPECIAL_expr}
		    {external 1 flag}
		}

		# Define an array variable spread in different
		# pieces of buf variable and REGNAME register.
		DW_TAG_variable {
		    {DW_AT_name mix_array}
		    {DW_AT_type :$array_size_8_type_label}
		    {DW_AT_location {

			# a byte piece located in a
			# fourth byte of the buf variable.
			DW_OP_addr $buf_var
			DW_OP_LLVM_offset_constu 3
			DW_OP_piece 0x1

			# a byte piece located in a
			# third byte of the buf variable.
			DW_OP_addr $buf_var
			DW_OP_lit2
			DW_OP_LLVM_offset
			DW_OP_piece 0x1

			# a byte piece located in a second byte of
			# the buf variable with a bit offset of one.
			DW_OP_addr $buf_var
			DW_OP_lit1
			DW_OP_LLVM_offset
			DW_OP_lit1
			DW_OP_LLVM_bit_offset
			DW_OP_piece 0x1

			# a four bit piece located in a first byte
			# of the buf variable with a bit offset of one.
			DW_OP_addr $buf_var
			DW_OP_LLVM_offset_constu 0
			DW_OP_bit_piece 0x4 0x1

			# a four bit piece located in a first byte of
			# the buf variable with a bit offset of eight.
			DW_OP_addr $buf_var
			DW_OP_lit1
			DW_OP_LLVM_bit_offset
			DW_OP_LLVM_offset_constu 0
			DW_OP_bit_piece 0x4 0x7

			# a byte piece located in a fourth
			# byte of the REGNAME register.
			DW_OP_regx $dwarf_regnum
			DW_OP_LLVM_offset_constu 3
			DW_OP_piece 0x1

			# a byte piece located in a third
			# byte of the REGNAME register.
			DW_OP_regx $dwarf_regnum
			DW_OP_lit2
			DW_OP_LLVM_offset
			DW_OP_piece 0x1

			# a byte piece located in a second byte of the
			# REGNAME register with a bit offset of one.
			DW_OP_regx $dwarf_regnum
			DW_OP_lit1
			DW_OP_LLVM_offset
			DW_OP_lit1
			DW_OP_LLVM_bit_offset
			DW_OP_piece 0x1

			# a four bit piece located in a first byte of
			# the REGNAME register with a bit offset of one.
			DW_OP_regx $dwarf_regnum
			DW_OP_LLVM_offset_constu 0
			DW_OP_bit_piece 0x4 0x1

			# a four bit piece located in a first byte of the
			# REGNAME register with a bit offset of eight.
			DW_OP_regx $dwarf_regnum
			DW_OP_lit1
			DW_OP_LLVM_bit_offset
			DW_OP_LLVM_offset_constu 0
			DW_OP_bit_piece 0x4 0x7

		    } SPECIAL_expr}
		    {external 1 flag}
		}
	    }
	}
    }
}

if { [prepare_for_testing ${testfile}.exp ${testfile} \
     [list $srcfile $asm_file] {nodebug}] } {
    return -1
}

if ![runto_main] {
    return -1
}

# Determine byte order.
set endian [get_endianness]

if { $endian != "little" } then {
    verbose "Skipping ${gdb_test_file_name}."
    return
}

gdb_test_no_output "set var \$$regname = 0x04030201" "init reg"
gdb_test_no_output "set var *\(\(unsigned int *\) buf\) = 0x04030201" \
		   "init buf"

gdb_test "print/x buf_byte_3" " = 0x3" "buf_byte_3 == 0x3"
gdb_test "print/x buf_byte_2_bit_1" " = 0x81" \
	 "print buf_byte_2_bit_1"
gdb_test "print/x reg_byte_3" " = 0x3" "reg_byte_3 == 0x3"
gdb_test "print/x reg_byte_2_bit_1" " = 0x81" \
	 "print reg_byte_2_bit_1"

gdb_test_no_output "set var buf_byte_3 = 0x4" "init buf_byte_3 to 0x4"
gdb_test "print/x buf_byte_3" " = 0x4" "buf_byte_3 == 0x4"

gdb_test_no_output "set var buf_byte_2_bit_1 = 0x4" \
		   "init buf_byte_2_bit_1 to 0x4"
gdb_test "print/x buf_byte_2_bit_1" " = 0x4" "buf_byte_2_bit_1 == 0x4"

gdb_test "print/x buf" " = \\{0x1, 0x8, 0x4, 0x4\\}" "buf print"

gdb_test_no_output "set var reg_byte_3 = 0x4" "init reg_byte_3 to 0x4"
gdb_test "print/x reg_byte_3" " = 0x4" "reg_byte_3 == 0x4"

gdb_test_no_output "set var reg_byte_2_bit_1 = 0x4" \
		   "init reg_byte_2_bit_1 to 0x4"
gdb_test "print/x reg_byte_2_bit_1" " = 0x4" "reg_byte_2_bit_1 == 0x4"

gdb_test "print/x \$$regname" " = 0x4040801" "\$$regname print"

gdb_test_no_output "set var \$$regname = 0x04030201" "reset reg"
gdb_test_no_output "set var *\(\(unsigned int *\) buf\) = 0x04030201" \
		   "reset buf"

gdb_test "print/x mix_array" \
	 " = \\{0x4, 0x3, 0x81, 0x20, 0x4, 0x3, 0x81, 0x20\\}" \
	 "mix_array print"

gdb_test_no_output "set var mix_array\[1\] = 0x4" \
		   "set mix_array second byte"
gdb_test_no_output "set var mix_array\[2\] = 0x4" \
		   "set mix_array third byte"
gdb_test_no_output "set var mix_array\[5\] = 0x4" \
		   "set mix_array fifth byte"
gdb_test_no_output "set var mix_array\[6\] = 0x4" \
		   "set mix_array sixth byte"

gdb_test "print/x mix_array" \
	 " = \\{0x4, 0x4, 0x4, 0x80, 0x4, 0x4, 0x4, 0x80\\}" \
	 "mix_array second print"

gdb_test "print/x buf" " = \\{0x1, 0x8, 0x4, 0x4\\}" "buf second print"

gdb_test "print/x \$$regname" " = 0x4040801" "\$$regname second print"