From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1853) id A60B73849AD5; Wed, 24 Apr 2024 14:27:06 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org A60B73849AD5 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1713968826; bh=2OMQZbQsm0sgAXvLVfcQOwde8LTDwuY5kcD1mJKYFp8=; h=From:To:Subject:Date:From; b=r6aeCBoJDNQCnNZ4n6UkLVoGvuKLFvBITnpYgU5ELg+JWAxRHK6ZKM+5Parr9n6Nh Nb0EjSxJnuyL+2Ns6YdISNPMFy89eAiTfHVGxHD88fUB3N+ru3ElvsDEDyQC8WZjkF /6bdr75Jx+zkqiC+g5GcZpFV2DvJEuc4O7S6J3nM= Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable From: Bernd Edlinger To: gdb-cvs@sourceware.org Subject: [binutils-gdb] Handle two-linetable function in find_epilogue_using_linetable X-Act-Checkin: binutils-gdb X-Git-Author: Bernd Edlinger X-Git-Refname: refs/heads/master X-Git-Oldrev: 63ddc8af5d7d3ad909aad66291f23507ba987bb4 X-Git-Newrev: 730f5068f5fb6613e4faa2efc2309cd107562cbd Message-Id: <20240424142706.A60B73849AD5@sourceware.org> Date: Wed, 24 Apr 2024 14:27:06 +0000 (GMT) List-Id: https://sourceware.org/git/gitweb.cgi?p=3Dbinutils-gdb.git;h=3D730f5068f5fb= 6613e4faa2efc2309cd107562cbd commit 730f5068f5fb6613e4faa2efc2309cd107562cbd Author: Bernd Edlinger Date: Tue Apr 9 09:27:53 2024 +0000 Handle two-linetable function in find_epilogue_using_linetable =20 Consider the following test-case: ... $ cat hello.c int main() { printf("hello "); #include "world.inc" $ cat world.inc printf("world\n"); return 0; } $ gcc -g hello.c ... =20 The line table for the compilation unit, consisting just of function main, is translated into these two gdb line tables, one for he= llo.c and one for world.inc: ... compunit_symtab: hello.c symtab: hello.c INDEX LINE REL-ADDRESS UNREL-ADDRESS IS-STMT PROLOGUE-END EPILOGUE-B= EGIN 0 3 0x400557 0x400557 Y 1 4 0x40055b 0x40055b Y 2 END 0x40056a 0x40056a Y =20 compunit_symtab: hello.c symtab: world.inc INDEX LINE REL-ADDRESS UNREL-ADDRESS IS-STMT PROLOGUE-END EPILOGUE-B= EGIN 0 1 0x40056a 0x40056a Y 1 2 0x400574 0x400574 Y 2 3 0x400579 0x400579 Y 3 END 0x40057b 0x40057b Y ... =20 The epilogue of main starts at 0x400579: ... 400579: 5d pop %rbp 40057a: c3 ret ... =20 Now, say we have an epilogue_begin marker in the line table at 0x400579. =20 We won't find it using find_epilogue_using_linetable, because it does: ... const struct symtab_and_line sal =3D find_pc_line (start_pc, 0); ... which gets us the line table for hello.c. =20 Fix this by using "find_pc_line (end_pc - 1, 0)" instead. =20 Tested on x86_64-linux. =20 Co-Authored-By: Tom de Vries =20 PR symtab/31622 Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=3D31622 Diff: --- gdb/symtab.c | 11 +- gdb/testsuite/gdb.dwarf2/dw2-epilogue-begin-2.exp | 20 +++ gdb/testsuite/gdb.dwarf2/dw2-epilogue-begin.c.inc | 51 ++++++ gdb/testsuite/gdb.dwarf2/dw2-epilogue-begin.exp | 158 +--------------- .../gdb.dwarf2/dw2-epilogue-begin.exp.tcl | 199 +++++++++++++++++= ++++ gdb/testsuite/lib/dwarf.exp | 5 +- 6 files changed, 284 insertions(+), 160 deletions(-) diff --git a/gdb/symtab.c b/gdb/symtab.c index 06b32c03884..6d3732aee8c 100644 --- a/gdb/symtab.c +++ b/gdb/symtab.c @@ -4159,8 +4159,15 @@ find_epilogue_using_linetable (CORE_ADDR func_addr) =20 /* While the standard allows for multiple points marked with epilogue_be= gin in the same function, for performance reasons, this function will only - find the last address that sets this flag for a given block. */ - const struct symtab_and_line sal =3D find_pc_line (start_pc, 0); + find the last address that sets this flag for a given block. + + The lines of a function can be described by several line tables in ca= se + there are different files involved. There's a corner case where a + function epilogue is in a different file than a function start, and u= sing + start_pc as argument to find_pc_line will mean we won't find the + epilogue. Instead, use "end_pc - 1" to maximize our chances of picki= ng + the line table containing an epilogue. */ + const struct symtab_and_line sal =3D find_pc_line (end_pc - 1, 0); if (sal.symtab !=3D nullptr && sal.symtab->language () !=3D language_asm) { struct objfile *objfile =3D sal.symtab->compunit ()->objfile (); diff --git a/gdb/testsuite/gdb.dwarf2/dw2-epilogue-begin-2.exp b/gdb/testsu= ite/gdb.dwarf2/dw2-epilogue-begin-2.exp new file mode 100644 index 00000000000..6302ef1ad05 --- /dev/null +++ b/gdb/testsuite/gdb.dwarf2/dw2-epilogue-begin-2.exp @@ -0,0 +1,20 @@ +# Copyright 2022-2024 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 . + +standard_testfile dw2-epilogue-begin.c dw2-epilogue-begin.S + +set version 2 + +source $srcdir/$subdir/dw2-epilogue-begin.exp.tcl diff --git a/gdb/testsuite/gdb.dwarf2/dw2-epilogue-begin.c.inc b/gdb/testsu= ite/gdb.dwarf2/dw2-epilogue-begin.c.inc new file mode 100644 index 00000000000..4ff445cf37d --- /dev/null +++ b/gdb/testsuite/gdb.dwarf2/dw2-epilogue-begin.c.inc @@ -0,0 +1,51 @@ +/* Copyright 2023-2024 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 . = */ + +void +__attribute__((used)) +trivial (void) +{ + asm ("trivial_label: .global trivial_label"); /* trivial function */ +} + +char global; + +void +watch (void) +{ /* watch start */ + asm ("watch_label: .global watch_label"); + asm ("mov $0x0, %rax"); + int local =3D 0; /* watch prologue */ + + asm ("watch_start: .global watch_start"); + asm ("mov $0x1, %rax"); + local =3D 1; /* watch assign */ + asm ("watch_reassign: .global watch_reassign"); + asm ("mov $0x2, %rax"); + local =3D 2; /* watch reassign */ + asm ("watch_end: .global watch_end"); /* watch end */ +} + +int +main (void) +{ /* main prologue */ + asm ("main_label: .global main_label"); + global =3D 0; + asm ("main_fun_call: .global main_fun_call"); + watch (); /* main function call */ + asm ("main_epilogue: .global main_epilogue"); + global =3D 10; + return 0; /* main end */ +} diff --git a/gdb/testsuite/gdb.dwarf2/dw2-epilogue-begin.exp b/gdb/testsuit= e/gdb.dwarf2/dw2-epilogue-begin.exp index 7ae14fa9b5a..9b9d6c71de4 100644 --- a/gdb/testsuite/gdb.dwarf2/dw2-epilogue-begin.exp +++ b/gdb/testsuite/gdb.dwarf2/dw2-epilogue-begin.exp @@ -13,162 +13,8 @@ # You should have received a copy of the GNU General Public License # along with this program. If not, see . =20 -# Check that GDB can honor the epilogue_begin flag the compiler can place -# in the line-table data. -# We test 2 things: 1. that a software watchpoint triggered in an epilogue -# is correctly ignored -# 2. that GDB can mark the same line as both prologue and epilogue - -load_lib dwarf.exp - -# This test can only be run on targets which support DWARF-2 and use gas. -require dwarf2_support -# restricted to x86 to make it simpler to follow a variable -require is_x86_64_m64_target - standard_testfile .c .S =20 -set trivial_line [gdb_get_line_number "trivial function"] -set main_prologue [gdb_get_line_number "main prologue"] -set main_epilogue [gdb_get_line_number "main end"] -set watch_start_line [gdb_get_line_number "watch start"] - -set asm_file [standard_output_file $srcfile2] - -# The producer will be set to clang because at the time of writing -# we only care about epilogues if the producer is clang. When the -# producer is GCC, variables use CFA locations, so watchpoints can -# continue working even on epilogues. -Dwarf::assemble $asm_file { - global srcdir subdir srcfile srcfile2 - global trivial_line main_prologue main_epilogue watch_start_line - declare_labels lines_label - - get_func_info main - get_func_info trivial - get_func_info watch - - cu {} { - compile_unit { - {language @DW_LANG_C} - {name dw2-prologue-end.c} - {stmt_list ${lines_label} DW_FORM_sec_offset} - {producer "clang version 17.0.1"} - } { - declare_labels char_label - - char_label: base_type { - {name char} - {encoding @DW_ATE_signed} - {byte_size 1 DW_FORM_sdata} - } - - subprogram { - {external 1 flag} - {name trivial} - {low_pc $trivial_start addr} - {high_pc "$trivial_start + $trivial_len" addr} - } - subprogram { - {external 1 flag} - {name watch} - {low_pc $watch_start addr} - {high_pc "$watch_start + $watch_len" addr} - } { - DW_TAG_variable { - {name local} - {type :$char_label} - {DW_AT_location {DW_OP_reg0} SPECIAL_expr} - } - } - subprogram { - {external 1 flag} - {name main} - {low_pc $main_start addr} - {high_pc "$main_start + $main_len" addr} - } - } - } - - lines {version 5} lines_label { - set diridx [include_dir "${srcdir}/${subdir}"] - file_name "$srcfile" $diridx - - program { - DW_LNS_set_file $diridx - DW_LNE_set_address $trivial_start - line $trivial_line - DW_LNS_set_prologue_end - DW_LNS_set_epilogue_begin - DW_LNS_copy - - DW_LNE_set_address watch - line $watch_start_line - DW_LNS_copy - - DW_LNE_set_address watch_start - line [gdb_get_line_number "watch assign"] - DW_LNS_set_prologue_end - DW_LNS_copy - - DW_LNE_set_address watch_reassign - line [gdb_get_line_number "watch reassign"] - DW_LNS_set_epilogue_begin - DW_LNS_copy - - DW_LNE_set_address watch_end - line [gdb_get_line_number "watch end"] - DW_LNS_copy - - DW_LNE_set_address $main_start - line $main_prologue - DW_LNS_set_prologue_end - DW_LNS_copy - - DW_LNE_set_address main_fun_call - line [gdb_get_line_number "main function call"] - DW_LNS_copy - - DW_LNE_set_address main_epilogue - line $main_epilogue - DW_LNS_set_epilogue_begin - DW_LNS_copy - - DW_LNE_set_address "$main_start + $main_len" - DW_LNE_end_sequence - } - } -} - -if { [prepare_for_testing "failed to prepare" ${testfile} \ - [list $srcfile $asm_file] {nodebug}] } { - return -1 -} - -if ![runto_main] { - return -1 -} - -# Moving to the scope with a local variable. -gdb_breakpoint $watch_start_line -gdb_continue_to_breakpoint "continuing to function" ".*" -gdb_test "next" "local =3D 2.*" "stepping to epilogue" - -# Forcing software watchpoints because hardware ones don't care if we -# are in the epilogue or not. -gdb_test_no_output "set can-use-hw-watchpoints 0" - -# Test that the software watchpoint will not trigger in this case -gdb_test "watch local" "\[W|w\]atchpoint .: local" "set watchpoint" -gdb_test "continue" ".*\[W|w\]atchpoint . deleted.*" \ - "confirm watchpoint doesn't trigger" +set version 1 =20 -# First we test that the trivial function has a line with both a prologue -# and an epilogue. Do this by finding a line that has 3 Y columns -set sep "\[ \t\]" -set hex_number "0x\[0-9a-f\]+" -gdb_test_multiple "maint info line-table" "test epilogue in linetable" -lb= l { - -re "\[0-9\]$sep+$trivial_line$sep+$hex_number$sep+$hex_number$sep+Y$s= ep+Y$sep+Y" { - pass $gdb_test_name - } -} +source $srcdir/$subdir/dw2-epilogue-begin.exp.tcl diff --git a/gdb/testsuite/gdb.dwarf2/dw2-epilogue-begin.exp.tcl b/gdb/test= suite/gdb.dwarf2/dw2-epilogue-begin.exp.tcl new file mode 100644 index 00000000000..155916b92df --- /dev/null +++ b/gdb/testsuite/gdb.dwarf2/dw2-epilogue-begin.exp.tcl @@ -0,0 +1,199 @@ +# Copyright 2022-2024 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 . + +# Check that GDB can honor the epilogue_begin flag the compiler can place +# in the line-table data. +# We test 2 things: 1. that a software watchpoint triggered in an epilogue +# is correctly ignored +# 2. that GDB can mark the same line as both prologue and epilogue + +load_lib dwarf.exp + +# This test can only be run on targets which support DWARF-2 and use gas. +require dwarf2_support +# restricted to x86 to make it simpler to follow a variable +require is_x86_64_m64_target + +set trivial_line [gdb_get_line_number "trivial function"] +set main_prologue [gdb_get_line_number "main prologue"] +set main_epilogue [gdb_get_line_number "main end"] +set watch_start_line [gdb_get_line_number "watch start"] + +set asm_file [standard_output_file $srcfile2] + +# The producer will be set to clang because at the time of writing +# we only care about epilogues if the producer is clang. When the +# producer is GCC, variables use CFA locations, so watchpoints can +# continue working even on epilogues. +Dwarf::assemble $asm_file { + global srcdir subdir srcfile srcfile2 + global trivial_line main_prologue main_epilogue watch_start_line + declare_labels lines_label + + get_func_info main + get_func_info trivial + get_func_info watch + + if { $::version =3D=3D 1 } { + set switch_file {} + } elseif { $::version =3D=3D 2 } { + set switch_file { set f $f2 } + } else { + error "Unhandled version: $::version" + } + + cu {} { + compile_unit { + {language @DW_LANG_C} + {name dw2-prologue-end.c} + {stmt_list ${lines_label} DW_FORM_sec_offset} + {producer "clang version 17.0.1"} + } { + declare_labels char_label + + char_label: base_type { + {name char} + {encoding @DW_ATE_signed} + {byte_size 1 DW_FORM_sdata} + } + + subprogram { + {external 1 flag} + {name trivial} + {low_pc $trivial_start addr} + {high_pc "$trivial_start + $trivial_len" addr} + } + subprogram { + {external 1 flag} + {name watch} + {low_pc $watch_start addr} + {high_pc "$watch_start + $watch_len" addr} + } { + DW_TAG_variable { + {name local} + {type :$char_label} + {DW_AT_location {DW_OP_reg0} SPECIAL_expr} + } + } + subprogram { + {external 1 flag} + {name main} + {low_pc $main_start addr} + {high_pc "$main_start + $main_len" addr} + } + } + } + + lines {version 5} lines_label { + set diridx [include_dir "${srcdir}/${subdir}"] + set f1 [file_name "$srcfile" $diridx] + set f2 [file_name "$srcfile.inc" $diridx] + + set f $f1 + program { + DW_LNS_set_file $f + + DW_LNE_set_address $trivial_start + line $trivial_line + DW_LNS_set_prologue_end + DW_LNS_set_epilogue_begin + DW_LNS_copy + + DW_LNE_set_address $trivial_end + DW_LNE_end_sequence + + + DW_LNS_set_file $f + + DW_LNE_set_address $watch_start + line $watch_start_line + DW_LNS_copy + + DW_LNE_set_address watch_start + line [gdb_get_line_number "watch assign"] + DW_LNS_set_prologue_end + DW_LNS_copy + + eval $switch_file + DW_LNS_set_file $f + + DW_LNE_set_address watch_reassign + line [gdb_get_line_number "watch reassign"] + DW_LNS_set_epilogue_begin + DW_LNS_copy + + DW_LNE_set_address watch_end + line [gdb_get_line_number "watch end"] + DW_LNS_copy + + DW_LNE_set_address $watch_end + DW_LNE_end_sequence + + + DW_LNS_set_file $f + + DW_LNE_set_address $main_start + line $main_prologue + DW_LNS_set_prologue_end + DW_LNS_copy + + DW_LNE_set_address main_fun_call + line [gdb_get_line_number "main function call"] + DW_LNS_copy + + DW_LNE_set_address main_epilogue + line $main_epilogue + DW_LNS_set_epilogue_begin + DW_LNS_copy + + DW_LNE_set_address $main_end + DW_LNE_end_sequence + } + } +} + +if { [prepare_for_testing "failed to prepare" ${testfile} \ + [list $srcfile $asm_file] {nodebug}] } { + return -1 +} + +if ![runto_main] { + return -1 +} + +# Moving to the scope with a local variable. + +gdb_breakpoint $srcfile:$watch_start_line +gdb_continue_to_breakpoint "continuing to function" ".*" +gdb_test "next" "local =3D 2.*" "stepping to epilogue" + +# Forcing software watchpoints because hardware ones don't care if we +# are in the epilogue or not. +gdb_test_no_output "set can-use-hw-watchpoints 0" + +# Test that the software watchpoint will not trigger in this case +gdb_test "watch local" "\[W|w\]atchpoint .: local" "set watchpoint" +gdb_test "continue" ".*\[W|w\]atchpoint . deleted.*" \ + "confirm watchpoint doesn't trigger" + +# First we test that the trivial function has a line with both a prologue +# and an epilogue. Do this by finding a line that has 3 Y columns +set sep "\[ \t\]" +set hex_number "0x\[0-9a-f\]+" +gdb_test_multiple "maint info line-table" "test epilogue in linetable" -lb= l { + -re "\[0-9\]$sep+$trivial_line$sep+$hex_number$sep+$hex_number$sep+Y$s= ep+Y$sep+Y" { + pass $gdb_test_name + } +} diff --git a/gdb/testsuite/lib/dwarf.exp b/gdb/testsuite/lib/dwarf.exp index 1a97f83f8e6..44862dbb339 100644 --- a/gdb/testsuite/lib/dwarf.exp +++ b/gdb/testsuite/lib/dwarf.exp @@ -2427,10 +2427,11 @@ namespace eval Dwarf { variable _line_file_names lappend _line_file_names $filename $diridx =20 + set nr_filenames [expr [llength $_line_file_names] / 2] if { $Dwarf::_line_unit_version >=3D 5 } { - return [expr [llength $_line_file_names] - 1] + return [expr $nr_filenames - 1] } else { - return [llength $_line_file_names] + return $nr_filenames } }