gdb/testsuite/gdb.base/gnu-ifunc.exp

   1 # Copyright (C) 2009-2018 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 if {[skip_shlib_tests]} {
  17     return 0
  18 }
  19
  20 standard_testfile .c
  21 set staticexecutable ${testfile}-static
  22 set staticbinfile [standard_output_file ${staticexecutable}]
  23
  24 set libfile "${testfile}-lib"
  25 set libsrc ${libfile}.c
  26
  27 set final_file "${testfile}-final"
  28 set final_src ${final_file}.c
  29
  30 if [get_compiler_info] {
  31     return -1
  32 }
  33
  34 # Return the binary suffix appended to program and library names to
  35 # make each testcase variant unique.
  36 proc make_binsuffix {resolver_attr resolver_debug final_debug} {
  37     return "$resolver_attr-$resolver_debug-$final_debug"
  38 }
  39
  40 # Compile the testcase.  RESOLVER_ATTR is true if we're testing with
  41 # an ifunc resolver that has a different name from the user symbol,
  42 # specified with GCC's __attribute__ ifunc.  RESOLVER_DEBUG is true
  43 # iff the resolver was compiled with debug info.  FINAL_DEBUG is true
  44 # iff the target function was compiled with debug info.
  45 proc build {resolver_attr resolver_debug final_debug} {
  46     global srcdir subdir srcfile binfile
  47     global libsrc lib_so libfile
  48     global exec_opts executable
  49     global hex gdb_prompt
  50     global final_file final_src
  51
  52     set suffix [make_binsuffix $resolver_attr $resolver_debug $final_debug]
  53
  54     set lib_so [standard_output_file ${libfile}-$suffix.so]
  55     # $lib_o must not have {debug}, it would override the STT_GNU_IFUNC ELF markers.
  56     set lib_o [standard_output_file ${libfile}-$suffix.o]
  57
  58     set exec_opts [list debug shlib=$lib_so]
  59
  60     set lib_opts {}
  61     set final_opts {}
  62
  63     if {$resolver_attr} {
  64         lappend lib_opts "additional_flags=-DIFUNC_RESOLVER_ATTR"
  65     }
  66
  67     if {$resolver_debug} {
  68         lappend lib_opts "debug"
  69     }
  70
  71     if {$final_debug} {
  72         lappend final_opts "debug"
  73     }
  74
  75     set final_o $final_file-$suffix.o
  76
  77     if { [gdb_compile_shlib ${srcdir}/${subdir}/$libsrc \
  78               $lib_so $lib_opts] != ""
  79          || [gdb_compile ${srcdir}/${subdir}/$final_src \
  80                  $final_o object $final_opts] != ""
  81          || [gdb_compile [list ${srcdir}/${subdir}/$srcfile $final_o] \
  82                  $binfile-$suffix executable $exec_opts] != ""} {
  83         untested "failed to compile testcase"
  84         return 0
  85     }
  86
  87     return 1
  88 }
  89
  90 # Test setting a breakpoint on a ifunc function before and after the
  91 # ifunc is resolved.  For the description of RESOLVER_ATTR,
  92 # RESOLVER_DEBUG and FINAL_DEBUG, see the "build" procedure above.
  93 proc_with_prefix set-break {resolver_attr resolver_debug final_debug} {
  94     global binfile libfile lib_so
  95     global hex decimal
  96     global gdb_prompt
  97
  98     set suffix [make_binsuffix $resolver_attr $resolver_debug $final_debug]
  99
 100     set lib_so [standard_output_file ${libfile}-$suffix.so]
 101     clean_restart $binfile-$suffix
 102     gdb_load_shlib ${lib_so}
 103
 104     if ![runto_main] then {
 105         fail "can't run to main"
 106         return 1
 107     }
 108
 109     gdb_breakpoint [gdb_get_line_number "break-at-call"]
 110     gdb_continue_to_breakpoint "break-at-call" ".*break-at-call.*"
 111
 112     set ws "\[ \t\]+"
 113     set dot "\\.?"
 114
 115     if {$resolver_attr} {
 116         set gnu_ifunc_resolver "gnu_ifunc_resolver"
 117     } else {
 118         set gnu_ifunc_resolver "gnu_ifunc"
 119     }
 120
 121     if {!$resolver_debug} {
 122         set gnu_ifunc_resolver "${dot}${gnu_ifunc_resolver}"
 123     }
 124
 125     if {!$final_debug} {
 126         set final "${dot}final"
 127     } else {
 128         set final "final"
 129     }
 130
 131     with_test_prefix "before resolving" {
 132         delete_breakpoints
 133         gdb_test "break gnu_ifunc" \
 134             "Breakpoint $decimal at gnu-indirect-function resolver at $hex"
 135         gdb_test "info breakpoints" \
 136             "$decimal${ws}STT_GNU_IFUNC resolver${ws}keep${ws}y${ws}$hex <${gnu_ifunc_resolver}>"
 137
 138         # Make the breakpoint conditional on a condition that always
 139         # fails.  This is so that when the ifunc-resolver breakpoint
 140         # triggers, GDB resumes the program immediately.
 141         gdb_test_no_output "condition \$bpnum 0"
 142     }
 143
 144     global final_src
 145
 146     with_test_prefix "resolve" {
 147         gdb_breakpoint [gdb_get_line_number "break-at-exit"]
 148         gdb_continue_to_breakpoint "break-at-exit" ".*break-at-exit.*"
 149     }
 150
 151     with_test_prefix "after resolving" {
 152         if {!$final_debug} {
 153             # Set a breakpoint both at the ifunc, and at the ifunc's
 154             # target.  GDB should resolve both to the same address.
 155             # Start with the ifunc's target.
 156             set addr "-"
 157             set test "break final"
 158             # Extract the address without the leading "0x", because
 159             # addresses in "info break" output include leading 0s
 160             # (like "0x0000ADDR").
 161             set hex_number {[0-9a-fA-F][0-9a-fA-F]*}
 162             gdb_test_multiple $test $test {
 163                 -re "Breakpoint .* at 0x($hex_number)\r\n$gdb_prompt $" {
 164                     set addr $expect_out(1,string)
 165                     pass $test
 166                 }
 167             }
 168
 169             # Now set a break at the ifunc.
 170             gdb_test "break gnu_ifunc" "Breakpoint .* at 0x$addr"
 171             set location "$decimal${ws}breakpoint${ws}keep${ws}y${ws}0x0*$addr${ws}<${final}\\+.*>"
 172         } else {
 173             set lineno -1
 174             set test "break final"
 175             gdb_test_multiple $test $test {
 176                 -re "Breakpoint .* at $hex: file .*$final_src, line ($decimal)\\.\r\n$gdb_prompt $" {
 177                     set lineno $expect_out(1,string)
 178                     pass $test
 179                 }
 180             }
 181             gdb_test "break gnu_ifunc" "Breakpoint .* at $hex: file .*$final_src, line $lineno\\."
 182             set location "$decimal${ws}breakpoint${ws}keep${ws}y${ws}$hex in final at .*$final_src:$lineno"
 183         }
 184
 185         # The first location here is for the breakpoint that was set
 186         # before the ifunc was resolved.  It should be resolved by
 187         # now, and it should have the exact same address/line as the
 188         # other two locations.
 189         gdb_test "info breakpoints" "$location\r\n.*$location\r\n$location"
 190     }
 191 }
 192
 193 # Misc GNU ifunc tests.  For the description of RESOLVER_ATTR,
 194 # RESOLVER_DEBUG and FINAL_DEBUG, see the "build" procedure above.
 195 proc misc_tests {resolver_attr resolver_debug final_debug} {
 196     global srcdir subdir srcfile binfile
 197     global libsrc lib_so libfile
 198     global exec_opts executable
 199     global hex gdb_prompt
 200     global final_file final_src
 201
 202     set suffix [make_binsuffix $resolver_attr $resolver_debug $final_debug]
 203
 204     if {$resolver_attr} {
 205         set gnu_ifunc_resolver "gnu_ifunc_resolver"
 206     } else {
 207         set gnu_ifunc_resolver "gnu_ifunc"
 208     }
 209
 210     set dot "\\.?"
 211
 212     if {!$resolver_debug} {
 213         set gnu_ifunc_resolver "${dot}${gnu_ifunc_resolver}"
 214     }
 215
 216     if {!$final_debug} {
 217         set final "${dot}final"
 218     } else {
 219         set final "final"
 220     }
 221
 222     # Start with a fresh gdb.
 223
 224     clean_restart $binfile-$suffix
 225     gdb_load_shlib ${lib_so}
 226
 227     if ![runto_main] then {
 228         fail "can't run to main"
 229         return 1
 230     }
 231
 232     # The "if" condition is artifical to test regression of a former patch.
 233     gdb_breakpoint "[gdb_get_line_number "break-at-nextcall"] if i && (int) gnu_ifunc (i) != 42"
 234
 235     gdb_breakpoint [gdb_get_line_number "break-at-call"]
 236     gdb_continue_to_breakpoint "break-at-call" ".*break-at-call.*"
 237
 238     # Test GDB will automatically indirect the call.
 239
 240     if {!$resolver_debug && !$final_debug} {
 241         gdb_test "p gnu_ifunc()" \
 242             "'${dot}final' has unknown return type; cast the call to its declared return type"
 243         gdb_test "p gnu_ifunc (3)" \
 244             "'${dot}final' has unknown return type; cast the call to its declared return type"
 245         gdb_test "p (int) gnu_ifunc (3)" " = 4"
 246     } else {
 247         gdb_test "p gnu_ifunc()" "Too few arguments in function call\\."
 248         gdb_test "p gnu_ifunc (3)" " = 4"
 249     }
 250
 251     # Test that the resolver received its argument.
 252
 253     set actual_hwcap "0x0"
 254     set test "info auxv"
 255     gdb_test_multiple $test $test {
 256         -re "\r\n\\d+\\s+AT_HWCAP\[^\r\n\]+($hex)\r\n.*$gdb_prompt $" {
 257             set actual_hwcap $expect_out(1,string)
 258         }
 259         -re ".*$gdb_prompt $" {
 260             pass "$test (no HWCAP)"
 261         }
 262     }
 263
 264     gdb_test "p/x resolver_hwcap" "= $actual_hwcap" "resolver received HWCAP"
 265
 266     # Test GDB will skip the gnu_ifunc resolver on first call.
 267
 268     # Even if the resolver has debug info, stepping into an ifunc call
 269     # should skip the resolver.
 270     if {!$final_debug} {
 271         # Make GDB stop stepping even if it steps into a function with
 272         # no debug info.
 273         gdb_test_no_output "set step-mode on"
 274         gdb_test "step" "$hex in ${dot}final \\\(\\\)"
 275     } else {
 276         gdb_test "step" "\r\nfinal .*"
 277     }
 278
 279     # Test GDB will not break before the final chosen implementation.
 280
 281     # Also test a former patch regression:
 282     # Continuing.
 283     # Error in testing breakpoint condition:
 284     # Attempt to take address of value not located in memory.
 285     #
 286     # Breakpoint 2, main () at ./gdb.base/gnu-ifunc.c:33
 287
 288     gdb_test "continue" \
 289         "Continuing.\r\n\r\nBreakpoint .* (at|in) .*break-at-nextcall.*" \
 290         "continue to break-at-nextcall"
 291
 292     gdb_breakpoint "gnu_ifunc"
 293
 294     gdb_continue_to_breakpoint "nextcall gnu_ifunc"
 295
 296     gdb_test "frame" \
 297         "#0 +(0x\[0-9a-f\]+ in +)?${final} \\(.*" "nextcall gnu_ifunc skipped"
 298
 299     # Check any commands not doing an inferior call access the address of the
 300     # STT_GNU_IFUNC resolver, not the target function.
 301
 302     if {[istarget powerpc64-*] && [is_lp64_target]} {
 303         # With only minimal symbols GDB provides the function descriptors.  With
 304         # full debug info the function code would be displayed.
 305     }
 306
 307     gdb_test "p gnu_ifunc" \
 308         " = {<text gnu-indirect-function variable, no debug info>} 0x\[0-9a-f\]+ <${gnu_ifunc_resolver}>" \
 309         "p gnu_ifunc executing"
 310     gdb_test "info sym gnu_ifunc" \
 311         "${gnu_ifunc_resolver} in section .*" \
 312         "info sym gnu_ifunc executing"
 313
 314     set test "info addr gnu_ifunc"
 315     if {!$resolver_attr && $resolver_debug} {
 316         gdb_test_multiple $test $test {
 317             -re "Symbol \"gnu_ifunc\" is a function at address (0x\[0-9a-f\]+).*$gdb_prompt $" {
 318                 pass $test
 319             }
 320         }
 321     } else {
 322         gdb_test_multiple $test $test {
 323             -re "Symbol \"gnu_ifunc\" is at (0x\[0-9a-f\]+) in .*$gdb_prompt $" {
 324                 pass $test
 325             }
 326         }
 327     }
 328     gdb_test "info sym $expect_out(1,string)" \
 329         "${gnu_ifunc_resolver} in section .*" \
 330         "info sym <gnu_ifunc-address>"
 331
 332     # Test calling the resolver directly instead of the ifunc symbol.
 333     # Can only do that if the ifunc and the ifunc resolver have
 334     # different names.
 335     if {$resolver_attr} {
 336         if {$resolver_debug} {
 337             if {[istarget powerpc64-*] && [is_lp64_target]} {
 338                 gdb_test "p gnu_ifunc_resolver(0)" \
 339                     " = \\(int \\(\\*\\)\\(int\\)\\) @$hex: $hex <${final}>"
 340             } else {
 341                 gdb_test "p gnu_ifunc_resolver(0)" \
 342                     " = \\(int \\(\\*\\)\\(int\\)\\) $hex <final>"
 343             }
 344         } else {
 345             gdb_test "p gnu_ifunc_resolver(0)" \
 346                 "'${gnu_ifunc_resolver}' has unknown return type; cast the call to its declared return type"
 347             gdb_test "p (void *) gnu_ifunc_resolver(0)" \
 348                 " = \\(void \\*\\) $hex <${final}>"
 349         }
 350     }
 351 }
 352
 353 # Test all the combinations of:
 354 #
 355 # - An ifunc resolver with the same name as the ifunc symbol vs an
 356 #   ifunc resolver with a different name as the ifunc symbol.
 357 #
 358 # - ifunc resolver compiled with and without debug info.  This ensures
 359 #   that GDB understands that a function not a regular function by
 360 #   looking at the STT_GNU_IFUNC type in the elf symbols.  DWARF has
 361 #   no way to express the STT_GNU_IFUNC type.
 362 #
 363 # - ifunc target function (resolved) compiled with and without debug
 364 #   info.
 365 foreach_with_prefix resolver_attr {0 1} {
 366     foreach_with_prefix resolver_debug {0 1} {
 367         foreach_with_prefix final_debug {0 1} {
 368             build $resolver_attr $resolver_debug $final_debug
 369             misc_tests $resolver_attr $resolver_debug $final_debug
 370             set-break $resolver_attr $resolver_debug $final_debug
 371         }
 372     }
 373 }
 374
 375 # Test statically linked ifunc resolving during inferior start.
 376 # https://bugzilla.redhat.com/show_bug.cgi?id=624967
 377
 378 with_test_prefix "static" {
 379     # Compile $staticbinfile separately as it may exit on error
 380     # (ld/12595).
 381
 382     set lib_o [standard_output_file ${libfile}.o]
 383     set final_o [standard_output_file ${final_file}.o]
 384     if { [gdb_compile ${srcdir}/${subdir}/$libsrc $lib_o object {}] != ""
 385          || [gdb_compile ${srcdir}/${subdir}/$final_src $final_o object {}] != ""
 386          || [gdb_compile "${srcdir}/${subdir}/$srcfile $lib_o $final_o" \
 387                  $staticbinfile executable {debug}] != "" } {
 388         untested "failed to compile second testcase"
 389         return -1
 390     }
 391
 392     clean_restart $staticexecutable
 393
 394     gdb_breakpoint "gnu_ifunc"
 395     gdb_breakpoint "main"
 396     gdb_run_cmd
 397     gdb_test "" "Breakpoint \[0-9\]*, main .*" "static gnu_ifunc"
 398 }