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

# Copyright (C) 2022 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 the new DW_OP_LLVM_overlay operation.
#
# The test uses a composite location description, where variable buff
# address is used as a base location and a reg1 is used as an overlay
# location.

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 1}

if { [is_aarch64_target] } {
    set regname {x0 x1}
} elseif { [is_aarch32_target]
	   || [istarget "s390*-*-*" ]
	   || [istarget "powerpc*-*-*"]
	   || [istarget "rs6000*-*-aix*"] } {
    set regname {r0 r1}
} elseif { [is_x86_like_target] } {
    set regname {eax ecx}
} elseif { [is_amd64_regs_target] } {
    set regname {rax rdx}
} else {
    verbose "Skipping $gdb_test_file_name."
    return
}

standard_testfile .c -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 buff_src [gdb_target_symbol buff]

    set foo_result [function_range foo ${srcdir}/${subdir}/${srcfile}]
    set foo_start [lindex $foo_result 0]
    set foo_length [lindex $foo_result 1]

    cu {} {
	DW_TAG_compile_unit {
	    {DW_AT_name $srcfile}
	    {DW_AT_comp_dir /tmp}
	} {
	    declare_labels int_type_label uint_type_label array_type_label

	    uint_type_label: DW_TAG_base_type {
		{DW_AT_name "uint32_t"}
		{DW_AT_encoding @DW_ATE_unsigned}
		{DW_AT_byte_size 4 DW_FORM_sdata}
	    }

	    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}
	    }

	    array_type_label: DW_TAG_array_type {
		{DW_AT_type :$uint_type_label}
	    } {
		DW_TAG_subrange_type {
		    {DW_AT_type :$int_type_label}
		    {DW_AT_upper_bound 7 DW_FORM_udata}
		}
	    }

	    DW_TAG_subprogram {
		{DW_AT_name foo}
		{DW_AT_low_pc $foo_start addr}
		{DW_AT_high_pc $foo_length data8}
	    } {

		DW_TAG_variable {
		    {DW_AT_name dst_v1}
		    {DW_AT_type :$array_type_label}
		    {DW_AT_location {
			# 1. Memory location description of dst elements located in memory:
			DW_OP_addr $buff_src

			# 2. Register location description of element dst\[i\] is located in a register:
			DW_OP_regx [lindex $dwarf_regnum 1]

			# 3. Offset of the register within the memory of dst:
			DW_OP_bregx [lindex $dwarf_regnum 0] 0
			DW_OP_lit4
			DW_OP_mul

			# 4. The size of the register element:
			DW_OP_lit4

			# 5. Make a composite location description for dst that is the memory #1 with
			#    the register #2 positioned as an overlay at offset #3 of size #4:
			DW_OP_LLVM_overlay
		    } SPECIAL_expr}
		}

		DW_TAG_variable {
		    {DW_AT_name dst_v2}
		    {DW_AT_type :$array_type_label}
		    {DW_AT_location {
			# 1. Memory location description of dst elements located in memory:
			DW_OP_addr $buff_src

			# 2. Register location description of element dst\[i\] is located in a register:
			DW_OP_regx [lindex $dwarf_regnum 1]

			# 3. Offset of the register within the memory of dst:
			DW_OP_bregx [lindex $dwarf_regnum 0] 0
			DW_OP_lit4
			DW_OP_mul

			# 4. The size of the register element:
			DW_OP_lit4

			# 5. Make a composite location description for dst that is the memory #1 with
			#    the register #2 positioned as an overlay at offset #3 of size #4:
			DW_OP_LLVM_bit_overlay
		    } SPECIAL_expr}
		}

		DW_TAG_variable {
		    {DW_AT_name src}
		    {DW_AT_type :$array_type_label}
		    {DW_AT_location {
			DW_OP_addr $buff_src
		    } SPECIAL_expr}
		}

		DW_TAG_variable {
		    {DW_AT_name i}
		    {DW_AT_type :$int_type_label}
		    {DW_AT_location {
			DW_OP_regx [lindex $dwarf_regnum 0]
		    } SPECIAL_expr}
		}
	    }
	}
    }
}

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

if ![runto_main] {
    return -1
}

gdb_test "break foo" "Breakpoint.*at.*" "break at function foo"
gdb_test "continue"  "Continuing\\..*Breakpoint \[0-9\]+,.*foo \\(\\).*" \
	 "continue to foo"

gdb_test_no_output "set var \$[lindex $regname 0] = 0x0" "init reg 0"
gdb_test_no_output "set var \$[lindex $regname 1] = 0xdeadbeef" "init reg 1"

# gdb_interact

# Determine byte order.
set endian [get_endianness]

switch $endian {
	little {set val_v1 "0xdeadbeef, 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7"}
	big {set val_v1 "0x7, 0x6, 0x5, 0x4, 0x3, 0x2, 0x1, 0xdeadbeef"}
}

gdb_test "print/x dst_v1" " = \\{${val_v1}\\}" "dst_v1 print i = 0"

switch $endian {
	little {set val_v2 "0xf, 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7"}
	big {set val_v2 "0x7, 0x6, 0x5, 0x4, 0x3, 0x2, 0x1, 0xf"}
}

gdb_test "print/x dst_v2" " = \\{${val_v2}\\}" "dst_v2 print i = 0"

gdb_test_no_output "set var i = 0x2" "init reg 0 to 2"

switch $endian {
	little {set val_v1 "0x0, 0x1, 0xdeadbeef, 0x3, 0x4, 0x5, 0x6, 0x7"}
	big {set val_v1 "0x7, 0x6, 0x5, 0x4, 0x3, 0xdeadbeef, 0x1, 0x0"}
}

gdb_test "print/x dst_v1" " = \\{${val_v1}\\}" "dst_v1 print i = 2"

switch $endian {
	little {set val_v2 "0xf00, 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7"}
	big {set val_v2 "0x7, 0x6, 0x5, 0x4, 0x3, 0x2, 0x1, 0xf00"}
}

gdb_test "print/x dst_v2" " = \\{${val_v2}\\}" "dst_v2 print i = 2"