gdb/testsuite/gdb.dwarf2/symbol_needs_eval_fail.exp

   1 # Copyright 2017-2024 Free Software Foundation, Inc.
   2
   3 # This program is free software; you can redistribute it and/or modify
   4 # it under the terms of the GNU General Public License as published by
   5 # the Free Software Foundation; either version 3 of the License, or
   6 # (at your option) any later version.
   7 #
   8 # This program is distributed in the hope that it will be useful,
   9 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  10 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11 # GNU General Public License for more details.
  12 #
  13 # You should have received a copy of the GNU General Public License
  14 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  15
  16 # Test the symbol needs check mechanism if it assumes that faking
  17 # reads from a target is a safe thing to do.
  18 #
  19 # In particular, the test uses a relative branch DWARF operation to
  20 # hide a register read. If the target reads are indeed faked, the
  21 # result returned will be wrong.
  22
  23 load_lib dwarf.exp
  24
  25 # This test can only be run on targets which support DWARF-2 and use gas.
  26 require dwarf2_support
  27
  28 # Choose suitable integer registers for the test.
  29
  30 set dwarf_regnum 0
  31
  32 if { [is_aarch64_target] } {
  33     set regname x0
  34 } elseif { [is_aarch32_target]
  35            || [istarget "s390*-*-*" ]
  36            || [istarget "powerpc*-*-*"]
  37            || [istarget "rs6000*-*-aix*"] } {
  38     set regname r0
  39 } elseif { [is_x86_like_target] } {
  40     set regname eax
  41 } elseif { [is_amd64_regs_target] } {
  42     set regname rax
  43 } else {
  44     verbose "Skipping ${gdb_test_file_name}."
  45     return
  46 }
  47
  48 standard_testfile symbol_needs_eval.c ${gdb_test_file_name}-dw.S
  49
  50 if [prepare_for_testing "failed to prepare" $testfile $srcfile {debug}] {
  51     return
  52 }
  53
  54 set int_size [get_sizeof "int" -1]
  55
  56 # Make some DWARF for the test.
  57
  58 set asm_file [standard_output_file $srcfile2]
  59 Dwarf::assemble $asm_file {
  60     global dwarf_regnum regname int_size
  61
  62     set exec_mask_var [gdb_target_symbol exec_mask]
  63
  64     cu {} {
  65         DW_TAG_compile_unit {
  66             {DW_AT_name symbol_needs_eval.c}
  67             {DW_AT_comp_dir /tmp}
  68         } {
  69             declare_labels int_type_label
  70
  71             # define int type
  72             int_type_label: DW_TAG_base_type {
  73                 {DW_AT_name "int"}
  74                 {DW_AT_encoding @DW_ATE_signed}
  75                 {DW_AT_byte_size $int_size DW_FORM_sdata}
  76             }
  77
  78             # define artificial variable a
  79             DW_TAG_variable {
  80                 {DW_AT_name a}
  81                 {DW_AT_type :$int_type_label}
  82                 {DW_AT_location {
  83                     DW_OP_addr $exec_mask_var
  84                     DW_OP_deref_size $int_size
  85
  86                     # conditional jump to DW_OP_bregx
  87                     DW_OP_bra 4
  88                     DW_OP_lit0
  89
  90                     # jump to DW_OP_stack_value
  91                     DW_OP_skip 3
  92                     DW_OP_bregx $dwarf_regnum 0
  93                     DW_OP_stack_value
  94                 } SPECIAL_expr}
  95                 {external 1 flag}
  96             }
  97         }
  98     }
  99 }
 100
 101 if { [prepare_for_testing ${testfile}.exp ${testfile} \
 102      [list $srcfile $asm_file] {nodebug}] } {
 103     return -1
 104 }
 105
 106 # The variable's location expression requires a frame,
 107 # so an error should be reported.
 108 gdb_test "print/d a" "No frame selected." "variable a can't be printed"
 109
 110 if ![runto_main] {
 111     return -1
 112 }
 113
 114 gdb_test_no_output "set var \$$regname = 2" "init reg to 2"
 115
 116 gdb_test "print/d a" " = 2" "a == 2"