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

   1 # Copyright (C) 2009-2019 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 if {[skip_ifunc_tests]} {
  21     return 0
  22 }
  23
  24 standard_testfile .c
  25 set staticexecutable ${testfile}-static
  26 set staticbinfile [standard_output_file ${staticexecutable}]
  27
  28 set libfile "${testfile}-lib"
  29 set libsrc ${libfile}.c
  30
  31 set final_file "${testfile}-final"
  32 set final_src ${final_file}.c
  33
  34 if [get_compiler_info] {
  35     return -1
  36 }
  37
  38 # Return the binary suffix appended to program and library names to
  39 # make each testcase variant unique.
  40 proc make_binsuffix {resolver_attr resolver_debug final_debug} {
  41     return "$resolver_attr-$resolver_debug-$final_debug"
  42 }
  43
  44 # Compile the testcase.  RESOLVER_ATTR is true if we're testing with
  45 # an ifunc resolver that has a different name from the user symbol,
  46 # specified with GCC's __attribute__ ifunc.  RESOLVER_DEBUG is true
  47 # iff the resolver was compiled with debug info.  FINAL_DEBUG is true
  48 # iff the target function was compiled with debug info.
  49 proc build {resolver_attr resolver_debug final_debug} {
  50     global srcdir subdir srcfile binfile
  51     global libsrc lib_so libfile
  52     global exec_opts executable
  53     global hex gdb_prompt
  54     global final_file final_src
  55
  56     set suffix [make_binsuffix $resolver_attr $resolver_debug $final_debug]
  57
  58     set lib_so [standard_output_file ${libfile}-$suffix.so]
  59     # $lib_o must not have {debug}, it would override the STT_GNU_IFUNC ELF markers.
  60     set lib_o [standard_output_file ${libfile}-$suffix.o]
  61
  62     set exec_opts [list debug shlib=$lib_so]
  63
  64     set lib_opts {}
  65     set final_opts {}
  66
  67     if {$resolver_attr} {
  68         lappend lib_opts "additional_flags=-DIFUNC_RESOLVER_ATTR"
  69     }
  70
  71     if {$resolver_debug} {
  72         lappend lib_opts "debug"
  73     }
  74
  75     if {$final_debug} {
  76         lappend final_opts "debug"
  77     }
  78
  79     set final_o [standard_output_file $final_file-$suffix.o]
  80
  81     if { [gdb_compile_shlib ${srcdir}/${subdir}/$libsrc \
  82               $lib_so $lib_opts] != ""
  83          || [gdb_compile ${srcdir}/${subdir}/$final_src \
  84                  $final_o object $final_opts] != ""
  85          || [gdb_compile [list ${srcdir}/${subdir}/$srcfile $final_o] \
  86                  $binfile-$suffix executable $exec_opts] != ""} {
  87         untested "failed to compile testcase"
  88         return 0
  89     }
  90
  91     return 1
  92 }
  93
  94 # Test setting a breakpoint on a ifunc function before and after the
  95 # ifunc is resolved.  For the description of RESOLVER_ATTR,
  96 # RESOLVER_DEBUG and FINAL_DEBUG, see the "build" procedure above.
  97 proc_with_prefix set-break {resolver_attr resolver_debug final_debug} {
  98     global binfile libfile lib_so
  99     global hex decimal
 100     global gdb_prompt
 101
 102     set suffix [make_binsuffix $resolver_attr $resolver_debug $final_debug]
 103
 104     set lib_so [standard_output_file ${libfile}-$suffix.so]
 105     clean_restart $binfile-$suffix
 106     gdb_load_shlib ${lib_so}
 107
 108     if ![runto_main] then {
 109         fail "can't run to main"
 110         return 1
 111     }
 112
 113     gdb_breakpoint [gdb_get_line_number "break-at-call"]
 114     gdb_continue_to_breakpoint "break-at-call" ".*break-at-call.*"
 115
 116     set ws "\[ \t\]+"
 117     set dot "\\.?"
 118
 119     if {$resolver_attr} {
 120         set gnu_ifunc_resolver "gnu_ifunc_resolver"
 121     } else {
 122         set gnu_ifunc_resolver "gnu_ifunc"
 123     }
 124
 125     if {!$resolver_debug} {
 126         set gnu_ifunc_resolver "${dot}${gnu_ifunc_resolver}"
 127     }
 128
 129     if {!$final_debug} {
 130         set final "${dot}final"
 131     } else {
 132         set final "final"
 133     }
 134
 135     with_test_prefix "before resolving" {
 136         delete_breakpoints
 137         gdb_test "break gnu_ifunc" \
 138             "Breakpoint $decimal at gnu-indirect-function resolver at $hex"
 139         gdb_test "info breakpoints" \
 140             "$decimal${ws}STT_GNU_IFUNC resolver${ws}keep${ws}y${ws}$hex <${gnu_ifunc_resolver}>"
 141
 142         # Make the breakpoint conditional on a condition that always
 143         # fails.  This is so that when the ifunc-resolver breakpoint
 144         # triggers, GDB resumes the program immediately.
 145         gdb_test_no_output "condition \$bpnum 0"
 146     }
 147
 148     global final_src
 149
 150     with_test_prefix "resolve" {
 151         gdb_breakpoint [gdb_get_line_number "break-at-exit"]
 152         gdb_continue_to_breakpoint "break-at-exit" ".*break-at-exit.*"
 153     }
 154
 155     with_test_prefix "after resolving" {
 156         if {!$final_debug} {
 157             # Set a breakpoint both at the ifunc, and at the ifunc's
 158             # target.  GDB should resolve both to the same address.
 159             # Start with the ifunc's target.
 160             set addr "-"
 161             set test "break final"
 162             # Extract the address without the leading "0x", because
 163             # addresses in "info break" output include leading 0s
 164             # (like "0x0000ADDR").
 165             set hex_number {[0-9a-fA-F][0-9a-fA-F]*}
 166             gdb_test_multiple $test $test {
 167                 -re "Breakpoint .* at 0x($hex_number)\r\n$gdb_prompt $" {
 168                     set addr $expect_out(1,string)
 169                     pass $test
 170                 }
 171             }
 172
 173             # Now set a break at the ifunc.
 174             gdb_test "break gnu_ifunc" "Breakpoint .* at 0x$addr"
 175             set location "$decimal${ws}breakpoint${ws}keep${ws}y${ws}0x0*$addr${ws}<${final}\\+.*>"
 176         } else {
 177             set lineno -1
 178             set test "break final"
 179             gdb_test_multiple $test $test {
 180                 -re "Breakpoint .* at $hex: file .*$final_src, line ($decimal)\\.\r\n$gdb_prompt $" {
 181                     set lineno $expect_out(1,string)
 182                     pass $test
 183                 }
 184             }
 185             gdb_test "break gnu_ifunc" "Breakpoint .* at $hex: file .*$final_src, line $lineno\\."
 186             set location "$decimal${ws}breakpoint${ws}keep${ws}y${ws}$hex in final at .*$final_src:$lineno"
 187         }
 188
 189         # The first location here is for the breakpoint that was set
 190         # before the ifunc was resolved.  It should be resolved by
 191         # now, and it should have the exact same address/line as the
 192         # other two locations.
 193         gdb_test "info breakpoints" "$location\r\n.*$location\r\n$location"
 194     }
 195 }
 196
 197 # Misc GNU ifunc tests.  For the description of RESOLVER_ATTR,
 198 # RESOLVER_DEBUG and FINAL_DEBUG, see the "build" procedure above.
 199 proc misc_tests {resolver_attr resolver_debug final_debug} {
 200     global srcdir subdir srcfile binfile
 201     global libsrc lib_so libfile
 202     global exec_opts executable
 203     global hex gdb_prompt
 204     global final_file final_src
 205
 206     set suffix [make_binsuffix $resolver_attr $resolver_debug $final_debug]
 207
 208     if {$resolver_attr} {
 209         set gnu_ifunc_resolver "gnu_ifunc_resolver"
 210     } else {
 211         set gnu_ifunc_resolver "gnu_ifunc"
 212     }
 213
 214     set dot "\\.?"
 215
 216     if {!$resolver_debug} {
 217         set gnu_ifunc_resolver "${dot}${gnu_ifunc_resolver}"
 218     }
 219
 220     if {!$final_debug} {
 221         set final "${dot}final"
 222     } else {
 223         set final "final"
 224     }
 225
 226     # Start with a fresh gdb.
 227
 228     clean_restart $binfile-$suffix
 229     gdb_load_shlib ${lib_so}
 230
 231     if ![runto_main] then {
 232         fail "can't run to main"
 233         return 1
 234     }
 235
 236     # The "if" condition is artifical to test regression of a former patch.
 237     gdb_breakpoint "[gdb_get_line_number "break-at-nextcall"] if i && (int) gnu_ifunc (i) != 42"
 238
 239     gdb_breakpoint [gdb_get_line_number "break-at-call"]
 240     gdb_continue_to_breakpoint "break-at-call" ".*break-at-call.*"
 241
 242     # Test GDB will automatically indirect the call.
 243
 244     if {!$resolver_debug && !$final_debug} {
 245         gdb_test "p gnu_ifunc()" \
 246             "'${dot}final' has unknown return type; cast the call to its declared return type"
 247         gdb_test "p gnu_ifunc (3)" \
 248             "'${dot}final' has unknown return type; cast the call to its declared return type"
 249         gdb_test "p (int) gnu_ifunc (3)" " = 4"
 250     } else {
 251         gdb_test "p gnu_ifunc()" "Too few arguments in function call\\."
 252         gdb_test "p gnu_ifunc (3)" " = 4"
 253     }
 254
 255     # Test that the resolver received its argument.
 256
 257     set actual_hwcap "0x0"
 258     set test "info auxv"
 259     gdb_test_multiple $test $test {
 260         -re "\r\n\\d+\\s+AT_HWCAP\[^\r\n\]+($hex)\r\n.*$gdb_prompt $" {
 261             set actual_hwcap $expect_out(1,string)
 262         }
 263         -re ".*$gdb_prompt $" {
 264             pass "$test (no HWCAP)"
 265         }
 266     }
 267
 268     gdb_test "p/x resolver_hwcap" "= $actual_hwcap" "resolver received HWCAP"
 269
 270     # Test GDB will skip the gnu_ifunc resolver on first call.
 271
 272     # Even if the resolver has debug info, stepping into an ifunc call
 273     # should skip the resolver.
 274     if {!$final_debug} {
 275         # Make GDB stop stepping even if it steps into a function with
 276         # no debug info.
 277         gdb_test_no_output "set step-mode on"
 278         gdb_test "step" "$hex in ${dot}final \\\(\\\)"
 279     } else {
 280         gdb_test "step" "\r\nfinal .*"
 281     }
 282
 283     # Test GDB will not break before the final chosen implementation.
 284
 285     # Also test a former patch regression:
 286     # Continuing.
 287     # Error in testing breakpoint condition:
 288     # Attempt to take address of value not located in memory.
 289     #
 290     # Breakpoint 2, main () at ./gdb.base/gnu-ifunc.c:33
 291
 292     gdb_test "continue" \
 293         "Continuing.\r\n\r\nBreakpoint .* (at|in) .*break-at-nextcall.*" \
 294         "continue to break-at-nextcall"
 295
 296     gdb_breakpoint "gnu_ifunc"
 297
 298     gdb_continue_to_breakpoint "nextcall gnu_ifunc"
 299
 300     gdb_test "frame" \
 301         "#0 +(0x\[0-9a-f\]+ in +)?${final} \\(.*" "nextcall gnu_ifunc skipped"
 302
 303     # Check any commands not doing an inferior call access the address of the
 304     # STT_GNU_IFUNC resolver, not the target function.
 305
 306     if {[istarget powerpc64-*] && [is_lp64_target]} {
 307         # With only minimal symbols GDB provides the function descriptors.  With
 308         # full debug info the function code would be displayed.
 309     }
 310
 311     gdb_test "p gnu_ifunc" \
 312         " = {<text gnu-indirect-function variable, no debug info>} 0x\[0-9a-f\]+ <${gnu_ifunc_resolver}>" \
 313         "p gnu_ifunc executing"
 314     gdb_test "info sym gnu_ifunc" \
 315         "${gnu_ifunc_resolver} in section .*" \
 316         "info sym gnu_ifunc executing"
 317
 318     set test "info addr gnu_ifunc"
 319     if {!$resolver_attr && $resolver_debug} {
 320         gdb_test_multiple $test $test {
 321             -re "Symbol \"gnu_ifunc\" is a function at address (0x\[0-9a-f\]+).*$gdb_prompt $" {
 322                 pass $test
 323             }
 324         }
 325     } else {
 326         gdb_test_multiple $test $test {
 327             -re "Symbol \"gnu_ifunc\" is at (0x\[0-9a-f\]+) in .*$gdb_prompt $" {
 328                 pass $test
 329             }
 330         }
 331     }
 332     gdb_test "info sym $expect_out(1,string)" \
 333         "${gnu_ifunc_resolver} in section .*" \
 334         "info sym <gnu_ifunc-address>"
 335
 336     # Test calling the resolver directly instead of the ifunc symbol.
 337     # Can only do that if the ifunc and the ifunc resolver have
 338     # different names.
 339     if {$resolver_attr} {
 340         if {$resolver_debug} {
 341             if {[istarget powerpc64-*] && [is_lp64_target]} {
 342                 gdb_test "p gnu_ifunc_resolver(0)" \
 343                     " = \\(int \\(\\*\\)\\(int\\)\\) @$hex: $hex <${final}>"
 344             } else {
 345                 gdb_test "p gnu_ifunc_resolver(0)" \
 346                     " = \\(int \\(\\*\\)\\(int\\)\\) $hex <final>"
 347             }
 348         } else {
 349             gdb_test "p gnu_ifunc_resolver(0)" \
 350                 "'${gnu_ifunc_resolver}' has unknown return type; cast the call to its declared return type"
 351             gdb_test "p (void *) gnu_ifunc_resolver(0)" \
 352                 " = \\(void \\*\\) $hex <${final}>"
 353         }
 354     }
 355 }
 356
 357 # Test all the combinations of:
 358 #
 359 # - An ifunc resolver with the same name as the ifunc symbol vs an
 360 #   ifunc resolver with a different name as the ifunc symbol.
 361 #
 362 # - ifunc resolver compiled with and without debug info.  This ensures
 363 #   that GDB understands that a function not a regular function by
 364 #   looking at the STT_GNU_IFUNC type in the elf symbols.  DWARF has
 365 #   no way to express the STT_GNU_IFUNC type.
 366 #
 367 # - ifunc target function (resolved) compiled with and without debug
 368 #   info.
 369 foreach_with_prefix resolver_attr {0 1} {
 370     foreach_with_prefix resolver_debug {0 1} {
 371         foreach_with_prefix final_debug {0 1} {
 372             if { [build $resolver_attr $resolver_debug $final_debug] != 0 } {
 373                 misc_tests $resolver_attr $resolver_debug $final_debug
 374                 set-break $resolver_attr $resolver_debug $final_debug
 375             }
 376         }
 377     }
 378 }
 379
 380 # Test statically linked ifunc resolving during inferior start.
 381 # https://bugzilla.redhat.com/show_bug.cgi?id=624967
 382
 383 with_test_prefix "static" {
 384     # Compile $staticbinfile separately as it may exit on error
 385     # (ld/12595).
 386
 387     set lib_o [standard_output_file ${libfile}.o]
 388     set final_o [standard_output_file ${final_file}.o]
 389     if { [gdb_compile ${srcdir}/${subdir}/$libsrc $lib_o object {}] != ""
 390          || [gdb_compile ${srcdir}/${subdir}/$final_src $final_o object {}] != ""
 391          || [gdb_compile "${srcdir}/${subdir}/$srcfile $lib_o $final_o" \
 392                  $staticbinfile executable {debug}] != "" } {
 393         untested "failed to compile second testcase"
 394         return -1
 395     }
 396
 397     clean_restart $staticexecutable
 398
 399     gdb_breakpoint "gnu_ifunc"
 400     gdb_breakpoint "main"
 401     gdb_run_cmd
 402     gdb_test "" "Breakpoint \[0-9\]*, main .*" "static gnu_ifunc"
 403 }