# Copyright (C) 2009-2022 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 . if {[skip_shlib_tests]} { return 0 } if {[skip_ifunc_tests]} { return 0 } standard_testfile .c set staticexecutable ${testfile}-static set staticbinfile [standard_output_file ${staticexecutable}] set libfile "${testfile}-lib" set libsrc ${libfile}.c set final_file "${testfile}-final" set final_src ${final_file}.c # Return the binary suffix appended to program and library names to # make each testcase variant unique. proc make_binsuffix {resolver_attr resolver_debug final_debug} { return "$resolver_attr-$resolver_debug-$final_debug" } # Compile the testcase. RESOLVER_ATTR is true if we're testing with # an ifunc resolver that has a different name from the user symbol, # specified with GCC's __attribute__ ifunc. RESOLVER_DEBUG is true # iff the resolver was compiled with debug info. FINAL_DEBUG is true # iff the target function was compiled with debug info. proc build {resolver_attr resolver_debug final_debug} { global srcdir subdir srcfile binfile global libsrc lib_so libfile global exec_opts executable global hex gdb_prompt global final_file final_src set suffix [make_binsuffix $resolver_attr $resolver_debug $final_debug] set lib_so [standard_output_file ${libfile}-$suffix.so] # $lib_o must not have {debug}, it would override the STT_GNU_IFUNC ELF markers. set lib_o [standard_output_file ${libfile}-$suffix.o] set exec_opts [list debug shlib=$lib_so] set lib_opts {} set final_opts {} # Force lazy binding so we don't resolve everything at process startup. lappend exec_opts "ldflags=-Wl,-z,lazy" lappend lib_opts "ldflags=-Wl,-z,lazy" if {$resolver_attr} { lappend lib_opts "additional_flags=-DIFUNC_RESOLVER_ATTR" } if {$resolver_debug} { lappend lib_opts "debug" } if {$final_debug} { lappend final_opts "debug" } set final_o [standard_output_file $final_file-$suffix.o] if { [gdb_compile_shlib ${srcdir}/${subdir}/$libsrc \ $lib_so $lib_opts] != "" || [gdb_compile ${srcdir}/${subdir}/$final_src \ $final_o object $final_opts] != "" || [gdb_compile [list ${srcdir}/${subdir}/$srcfile $final_o] \ $binfile-$suffix executable $exec_opts] != ""} { untested "failed to compile testcase" return 0 } return 1 } # Test setting a breakpoint on a ifunc function before and after the # ifunc is resolved. For the description of RESOLVER_ATTR, # RESOLVER_DEBUG and FINAL_DEBUG, see the "build" procedure above. proc_with_prefix set-break {resolver_attr resolver_debug final_debug} { global binfile libfile lib_so global hex decimal global gdb_prompt set suffix [make_binsuffix $resolver_attr $resolver_debug $final_debug] set lib_so [standard_output_file ${libfile}-$suffix.so] clean_restart $binfile-$suffix gdb_load_shlib ${lib_so} if {![runto_main]} { return 1 } gdb_breakpoint [gdb_get_line_number "break-at-call"] gdb_continue_to_breakpoint "break-at-call" ".*break-at-call.*" set ws "\[ \t\]+" set dot "\\.?" if {$resolver_attr} { set gnu_ifunc_resolver "gnu_ifunc_resolver" } else { set gnu_ifunc_resolver "gnu_ifunc" } if {!$resolver_debug} { set gnu_ifunc_resolver "${dot}${gnu_ifunc_resolver}" } if {!$final_debug} { set final "${dot}final" } else { set final "final" } with_test_prefix "before resolving" { delete_breakpoints gdb_test "break gnu_ifunc" \ "Breakpoint $decimal at gnu-indirect-function resolver at $hex" gdb_test "info breakpoints" \ "$decimal${ws}STT_GNU_IFUNC resolver${ws}keep${ws}y${ws}$hex <${gnu_ifunc_resolver}>" # Make the breakpoint conditional on a condition that always # fails. This is so that when the ifunc-resolver breakpoint # triggers, GDB resumes the program immediately. gdb_test_no_output "condition \$bpnum 0" } global final_src with_test_prefix "resolve" { gdb_breakpoint [gdb_get_line_number "break-at-exit"] gdb_continue_to_breakpoint "break-at-exit" ".*break-at-exit.*" } with_test_prefix "after resolving" { if {!$final_debug} { # Set a breakpoint both at the ifunc, and at the ifunc's # target. GDB should resolve both to the same address. # Start with the ifunc's target. set addr "-" set test "break final" # Extract the address without the leading "0x", because # addresses in "info break" output include leading 0s # (like "0x0000ADDR"). set hex_number {[0-9a-fA-F][0-9a-fA-F]*} gdb_test_multiple $test $test { -re "Breakpoint .* at 0x($hex_number)\r\n$gdb_prompt $" { set addr $expect_out(1,string) pass $test } } # Now set a break at the ifunc. gdb_test "break gnu_ifunc" "Breakpoint .* at 0x$addr" set location "$decimal${ws}breakpoint${ws}keep${ws}y${ws}0x0*$addr${ws}<${final}\\+.*>" } else { set lineno -1 set test "break final" gdb_test_multiple $test $test { -re "Breakpoint .* at $hex: file .*$final_src, line ($decimal)\\.\r\n$gdb_prompt $" { set lineno $expect_out(1,string) pass $test } } gdb_test "break gnu_ifunc" "Breakpoint .* at $hex: file .*$final_src, line $lineno\\." set location "$decimal${ws}breakpoint${ws}keep${ws}y${ws}$hex in final at .*$final_src:$lineno" } # The first location here is for the breakpoint that was set # before the ifunc was resolved. It should be resolved by # now, and it should have the exact same address/line as the # other two locations. gdb_test "info breakpoints" "$location\r\n.*$location\r\n$location" } } # Misc GNU ifunc tests. For the description of RESOLVER_ATTR, # RESOLVER_DEBUG and FINAL_DEBUG, see the "build" procedure above. proc misc_tests {resolver_attr resolver_debug final_debug} { global srcdir subdir srcfile binfile global libsrc lib_so libfile global exec_opts executable global hex gdb_prompt global final_file final_src set suffix [make_binsuffix $resolver_attr $resolver_debug $final_debug] if {$resolver_attr} { set gnu_ifunc_resolver "gnu_ifunc_resolver" } else { set gnu_ifunc_resolver "gnu_ifunc" } set dot "\\.?" if {!$resolver_debug} { set gnu_ifunc_resolver "${dot}${gnu_ifunc_resolver}" } if {!$final_debug} { set final "${dot}final" } else { set final "final" } # Start with a fresh gdb. clean_restart $binfile-$suffix gdb_load_shlib ${lib_so} if {![runto_main]} { return 1 } # The "if" condition is artifical to test regression of a former patch. gdb_breakpoint "[gdb_get_line_number "break-at-nextcall"] if i && (int) gnu_ifunc (i) != 42" gdb_breakpoint [gdb_get_line_number "break-at-call"] gdb_continue_to_breakpoint "break-at-call" ".*break-at-call.*" # Test GDB will automatically indirect the call. if {!$resolver_debug && !$final_debug} { gdb_test "p gnu_ifunc()" \ "'${dot}final' has unknown return type; cast the call to its declared return type" gdb_test "p gnu_ifunc (3)" \ "'${dot}final' has unknown return type; cast the call to its declared return type" gdb_test "p (int) gnu_ifunc (3)" " = 4" } else { gdb_test "p gnu_ifunc()" "Too few arguments in function call\\." gdb_test "p gnu_ifunc (3)" " = 4" } # Test that the resolver received its argument. set actual_hwcap "0x0" set test "info auxv" gdb_test_multiple $test $test { -re "\r\n\\d+\\s+AT_HWCAP\[^\r\n\]+($hex)\r\n.*$gdb_prompt $" { set actual_hwcap $expect_out(1,string) } -re ".*$gdb_prompt $" { pass "$test (no HWCAP)" } } gdb_test "p/x resolver_hwcap" "= $actual_hwcap" "resolver received HWCAP" # Test GDB will skip the gnu_ifunc resolver on first call. # Even if the resolver has debug info, stepping into an ifunc call # should skip the resolver. if {!$final_debug} { # Make GDB stop stepping even if it steps into a function with # no debug info. gdb_test_no_output "set step-mode on" gdb_test "step" "$hex in ${dot}final \\\(\\\)" } else { gdb_test "step" "\r\nfinal .*" } # Test GDB will not break before the final chosen implementation. # Also test a former patch regression: # Continuing. # Error in testing breakpoint condition: # Attempt to take address of value not located in memory. # # Breakpoint 2, main () at ./gdb.base/gnu-ifunc.c:33 gdb_test "continue" \ "Continuing.\r\n\r\nBreakpoint .* (at|in) .*break-at-nextcall.*" \ "continue to break-at-nextcall" gdb_breakpoint "gnu_ifunc" gdb_continue_to_breakpoint "nextcall gnu_ifunc" gdb_test "frame" \ "#0 +(0x\[0-9a-f\]+ in +)?${final} \\(.*" "nextcall gnu_ifunc skipped" # Check any commands not doing an inferior call access the address of the # STT_GNU_IFUNC resolver, not the target function. if {[istarget powerpc64-*] && [is_lp64_target]} { # With only minimal symbols GDB provides the function descriptors. With # full debug info the function code would be displayed. } gdb_test "p gnu_ifunc" \ " = {} 0x\[0-9a-f\]+ <${gnu_ifunc_resolver}>" \ "p gnu_ifunc executing" gdb_test "info sym gnu_ifunc" \ "${gnu_ifunc_resolver} in section .*" \ "info sym gnu_ifunc executing" set test "info addr gnu_ifunc" if {!$resolver_attr && $resolver_debug} { gdb_test_multiple $test $test { -re "Symbol \"gnu_ifunc\" is a function at address (0x\[0-9a-f\]+).*$gdb_prompt $" { pass $test } } } else { gdb_test_multiple $test $test { -re "Symbol \"gnu_ifunc\" is at (0x\[0-9a-f\]+) in .*$gdb_prompt $" { pass $test } } } gdb_test "info sym $expect_out(1,string)" \ "${gnu_ifunc_resolver} in section .*" \ "info sym " # Test calling the resolver directly instead of the ifunc symbol. # Can only do that if the ifunc and the ifunc resolver have # different names. if {$resolver_attr} { if {$resolver_debug} { if {[istarget powerpc64-*] && [is_lp64_target]} { gdb_test "p gnu_ifunc_resolver(0)" \ " = \\(int \\(\\*\\)\\(int\\)\\) @$hex: $hex <${final}>" } else { gdb_test "p gnu_ifunc_resolver(0)" \ " = \\(int \\(\\*\\)\\(int\\)\\) $hex " } } else { gdb_test "p gnu_ifunc_resolver(0)" \ "'${gnu_ifunc_resolver}' has unknown return type; cast the call to its declared return type" gdb_test "p (void *) gnu_ifunc_resolver(0)" \ " = \\(void \\*\\) $hex <${final}>" } } } # Test all the combinations of: # # - An ifunc resolver with the same name as the ifunc symbol vs an # ifunc resolver with a different name as the ifunc symbol. # # - ifunc resolver compiled with and without debug info. This ensures # that GDB understands that a function not a regular function by # looking at the STT_GNU_IFUNC type in the elf symbols. DWARF has # no way to express the STT_GNU_IFUNC type. # # - ifunc target function (resolved) compiled with and without debug # info. foreach_with_prefix resolver_attr {0 1} { foreach_with_prefix resolver_debug {0 1} { foreach_with_prefix final_debug {0 1} { if { [build $resolver_attr $resolver_debug $final_debug] != 0 } { misc_tests $resolver_attr $resolver_debug $final_debug set-break $resolver_attr $resolver_debug $final_debug } } } } # Test statically linked ifunc resolving during inferior start. # https://bugzilla.redhat.com/show_bug.cgi?id=624967 with_test_prefix "static" { # Compile $staticbinfile separately as it may exit on error # (ld/12595). set lib_o [standard_output_file ${libfile}.o] set final_o [standard_output_file ${final_file}.o] if { [gdb_compile ${srcdir}/${subdir}/$libsrc $lib_o object {}] != "" || [gdb_compile ${srcdir}/${subdir}/$final_src $final_o object {}] != "" || [gdb_compile "${srcdir}/${subdir}/$srcfile $lib_o $final_o" \ $staticbinfile executable {debug}] != "" } { untested "failed to compile second testcase" return -1 } clean_restart $staticexecutable gdb_breakpoint "gnu_ifunc" gdb_breakpoint "main" gdb_run_cmd gdb_test "" "Breakpoint \[0-9\]*, main .*" "static gnu_ifunc" }