From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 8513 invoked by alias); 18 May 2010 23:43:30 -0000 Received: (qmail 8490 invoked by uid 22791); 18 May 2010 23:43:23 -0000 X-SWARE-Spam-Status: No, hits=-5.4 required=5.0 tests=AWL,BAYES_00,KAM_STOCKGEN,RCVD_IN_DNSWL_HI,SPF_HELO_PASS,TW_TM,T_RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Tue, 18 May 2010 23:43:12 +0000 Received: from int-mx02.intmail.prod.int.phx2.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id o4INhA3e031404 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Tue, 18 May 2010 19:43:10 -0400 Received: from psique.localnet (vpn-241-243.phx2.redhat.com [10.3.241.243]) by int-mx02.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id o4INh8PW030859; Tue, 18 May 2010 19:43:08 -0400 From: Sergio Durigan Junior To: Jan Kratochvil Subject: Re: [PATCH] Forbid watchpoint on a constant value Date: Tue, 18 May 2010 23:50:00 -0000 User-Agent: KMail/1.13.2 (Linux/2.6.32.11-99.fc12.x86_64; KDE/4.4.2; x86_64; ; ) Cc: gdb-patches@sourceware.org References: <201005181418.24324.sergiodj@redhat.com> <20100518223106.GA12536@host0.dyn.jankratochvil.net> In-Reply-To: <20100518223106.GA12536@host0.dyn.jankratochvil.net> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201005182043.00433.sergiodj@redhat.com> X-IsSubscribed: yes Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org X-SW-Source: 2010-05/txt/msg00385.txt.bz2 Hi Jan, On Tuesday 18 May 2010 19:31:06, Jan Kratochvil wrote: > On Tue, 18 May 2010 19:18:22 +0200, Sergio Durigan Junior wrote: > > I have also included a testcase which is precompiled using -O2 on GCC. > > This test reproduces a problem that we were facing because of > > optimizations, so I thought it would be a good idea to include it. The > > problem is already solved, FWIW. > > The problem was that for some .debug_loc range is can be constant but it > does not mean the whole expression is constant. The attached testcase > contains: > > Contents of the .debug_loc section: > Offset Begin End Expression > 00000000 08048400 08048416 (DW_OP_lit5; DW_OP_stack_value) > 00000000 08048416 0804841e (DW_OP_reg3) > 00000000 > > The former patch had a bug for such -O2 -g code that at the first range it > rejects watching the variable claiming it is constant. > http://cvs.fedoraproject.org/viewvc/rpms/gdb/F-13/gdb-6.8-constant-watchpo > ints.patch?content-type=text%2Fplain&view=co Thanks for making it clearer :-). > > gdb/ChangeLog: > > > > 2010-05-18 Jan Kratochvil > > I would change the name order but I do not mind either way. Alphabetical order seemed the right choice to me :-). > > --- a/gdb/breakpoint.c > > +++ b/gdb/breakpoint.c > > @@ -1214,7 +1217,15 @@ is_watchpoint (const struct breakpoint *bpt) > > > > If VAL_CHAIN is non-NULL, *VAL_CHAIN will be released from the > > value chain. The caller must free the values individually. If > > VAL_CHAIN is NULL, all generated values will be left on the value > > > > - chain. */ > > + chain. > > + > > + Inferior unreachable values return: > > + Inferior `int *intp = NULL;' with `watch *intp': > > + *VALP is NULL, *RESULTP contains lazy LVAL_MEMORY address 0, > > *VAL_CHAIN + contains the *RESULTP element and also INTP as > > LVAL_MEMORY. + Inferior `int **intpp = NULL;' with `watch **intpp': > > + *VALP is NULL, *RESULTP is NULL, *VAL_CHAIN contains lazy > > LVAL_MEMORY + address 0 and also INTPP as LVAL_MEMORY. */ > > This comment extension is not relevant for this patch. It could be posted > separately. Former patch was using `struct value' for the evaluation but > your patch is using `struct expression'. Ops, sorry, that sneaked in... Will remove it, thanks. > > +/* This checks if each element of EXP is not a > > + constant expression for a watchpoint. > > + > > + Returns 1 if EXP is constant, 0 otherwise. */ > > +static int > > +watchpoint_exp_is_const (struct expression *exp) > > +{ > > + int i = 0; > > + > > + while (i < exp->nelts) > > + { > > + int oplenp, argsp; > > + > > + switch (exp->elts[i].opcode) > > + { > > + /* The user could provide something like: > > + > > + `watch *0xdeadbeef + 4' > > + > > + In this case, we need to check the remaining elements > > + of this expression. */ > > + case BINOP_ADD: > > + case BINOP_SUB: > > + case BINOP_MUL: > > > + case BINOP_DIV: > Many other math operations could be included (like BINOP_REM for one of the > many). One can check evaluate_subexp_standard to verify which of the ops > are really constant. OTOH I understand omitting them is not a regression > and their later inclusion would be possible by an incremental patch. Well, maybe it's a bad decision of mine, but I explicitly decided not to include the other types because I cannot see why the user would use it, i.e., the following command: (gdb) watch 5 % 2 doesn't make sense to me. > > + /* We are only interested in the descriptor of each element. */ > > + operator_length (exp, i + 1, &oplenp, &argsp); > > + i += oplenp; > > You must iterate backwards. When you check operator_length_standard it > uses expressions like `expr->elts[endpos - 2].longconst' expecting you > have given it index after the ending OP_* delimiter, not after the > starting OP_* delimiter. :-/ Fixed, thanks! > > --- /dev/null > > +++ b/gdb/testsuite/gdb.base/watch-notconst.c > > @@ -0,0 +1,23 @@ > > +/* The original program corresponding to watch-notconst.S. > > + > > + This program is not compiled; the .S version is used instead. > > + > > + The purpose of this test is to see if GDB can still watch the > > + variable `x' even when we compile the program using -O2 > > + optimization. */ > > Missing FSF copyleft header. Thanks. > > --- /dev/null > > +++ b/gdb/testsuite/gdb.base/watch-notconst.exp > > @@ -0,0 +1,43 @@ > > +# This test can only be run on x86 targets. > > +if {![istarget i?86-*] > > + && ![istarget "x86_64-*-*"]} { > > + return 0 > > +} > > Currently the .S files are i386-dependent and you do not provide > `additional_flags=-m32' to make it compatible with x86_64 hosts. > On x86_64 host it currently prints: > Running ./gdb.base/watch-notconst.exp ... > gdb compile failed, watch-notconst.c: Assembler messages: > watch-notconst.c:46: Error: suffix or operands invalid for `push' > watch-notconst.c:56: Error: suffix or operands invalid for `pop' > watch-notconst.c:78: Error: suffix or operands invalid for `push' > > Unfortunately `additional_flags=-m32' was rejected before: > Re: [patch] 3/3: New testcase on DW_OP_fbreg > From: Daniel Jacobowitz > http://sourceware.org/ml/gdb-patches/2008-05/msg00043.html > > Therefore suggesting to remove the "x86_64-*-*" possibility to make it > common with existing FSF GDB testcases. One has to always run the > testsuite also with `--target_board unix/-m32' to get its complete > results. Sorry, I put the "x86_64-*-*-*" check there in order to run the tests locally here, but I forgot to remove. By the way, for the testsuite-experts: is there any way to run the testcase on my machine (x86_64) without having to add `additional_flags=-m32' and the check for x86_64? I was trying to pass --target_board=unix/-m32 but that obviously didn't work... > > --- /dev/null > > +++ b/gdb/testsuite/gdb.base/watch-notconst2.c > > @@ -0,0 +1,18 @@ > > +/* The original program corresponding to watch-notconst2.S. > > + > > + This program is not compiled; the .S version is used instead. > > + > > + The purpose of this test is to see if GDB can still watch the > > + variable `x' even when we compile the program using -O2 > > + optimization. */ > > Missing FSF copyleft header. Thanks. -- Sergio Durigan Junior Red Hat diff --git a/gdb/breakpoint.c b/gdb/breakpoint.c index 0ee2258..d5a234d 100644 --- a/gdb/breakpoint.c +++ b/gdb/breakpoint.c @@ -61,6 +61,7 @@ #include "valprint.h" #include "jit.h" #include "xml-syscall.h" +#include "parser-defs.h" /* readline include files */ #include "readline/readline.h" @@ -186,6 +187,8 @@ static void stopin_command (char *arg, int from_tty); static void stopat_command (char *arg, int from_tty); +static int watchpoint_exp_is_const (struct expression *exp); + static char *ep_parse_optional_if_clause (char **arg); static void catch_exception_command_1 (enum exception_event_kind ex_event, @@ -7700,6 +7703,68 @@ stopat_command (char *arg, int from_tty) break_command_1 (arg, 0, from_tty); } +/* This checks if each element of EXP is not a + constant expression for a watchpoint. + + Returns 1 if EXP is constant, 0 otherwise. */ +static int +watchpoint_exp_is_const (struct expression *exp) +{ + int i = exp->nelts; + + while (i > 0) + { + int oplenp, argsp; + + /* We are only interested in the descriptor of each element. */ + operator_length (exp, i, &oplenp, &argsp); + i -= oplenp; + + switch (exp->elts[i].opcode) + { + /* The user could provide something like: + + `watch *0xdeadbeef + 4' + + In this case, we need to check the remaining elements + of this expression. */ + case BINOP_ADD: + case BINOP_SUB: + case BINOP_MUL: + case BINOP_DIV: + + case OP_LONG: + case OP_DOUBLE: + case OP_DECFLOAT: + + case UNOP_NEG: + case UNOP_PLUS: + break; + + /* If it's an OP_VAR_VALUE, then we must check if the `symbol' + element does not correspond to a function or to a constant + value. If it does, then it is a constant address. */ + case OP_VAR_VALUE: + { + struct symbol *s = exp->elts[i + 2].symbol; + + if (TYPE_CODE (SYMBOL_TYPE (s)) != TYPE_CODE_FUNC + && !TYPE_CONST (SYMBOL_TYPE (s))) + return 0; + break; + } + + /* The default action is to return 0 because we are using + the optimistic approach here: anything we don't know + is not a constant. */ + default: + return 0; + } + } + + return 1; +} + /* accessflag: hw_write: watch write, hw_read: watch read, hw_access: watch access (read or write) */ @@ -7797,6 +7862,18 @@ watch_command_1 (char *arg, int accessflag, int from_tty) exp_valid_block = innermost_block; mark = value_mark (); fetch_watchpoint_value (exp, &val, NULL, NULL); + + /* Checking if the expression is not constant. */ + if (watchpoint_exp_is_const (exp)) + { + int len; + + len = exp_end - exp_start; + while (len > 0 && isspace (exp_start[len - 1])) + len--; + error (_("Cannot watch constant value %.*s."), len, exp_start); + } + if (val != NULL) release_value (val); diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo index e929481..5d2d5f8 100644 --- a/gdb/doc/gdb.texinfo +++ b/gdb/doc/gdb.texinfo @@ -3725,6 +3725,18 @@ This command prints a list of watchpoints, using the same format as @code{info break} (@pxref{Set Breaks}). @end table +If you watch for a change in a numerically entered address you need to +dereference it, as the address itself is just a constant number which will +never change. @value{GDBN} refuses to create a watchpoint that watches +a never-changing value: + +@smallexample +(@value{GDBP}) watch 0x600850 +Cannot watch constant value 0x600850. +(@value{GDBP}) watch *(int *) 0x600850 +Watchpoint 1: *(int *) 6293584 +@end smallexample + @value{GDBN} sets a @dfn{hardware watchpoint} if possible. Hardware watchpoints execute very quickly, and the debugger reports a change in value at the exact instruction where the change occurs. If @value{GDBN} diff --git a/gdb/testsuite/gdb.base/watch-notconst.S b/gdb/testsuite/gdb.base/watch-notconst.S new file mode 100644 index 0000000..968b27b --- /dev/null +++ b/gdb/testsuite/gdb.base/watch-notconst.S @@ -0,0 +1,366 @@ +/* This testcase is part of GDB, the GNU debugger. + + Copyright 2010 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 . */ + +/* This source file was generated from watch-notconst.c using the following + command line: + + gcc -m32 -dA -S -g -O2 watch-notconst.c -o watch-notconst.S + +*/ + + .file "watch-notconst.c" + .section .debug_abbrev,"",@progbits +.Ldebug_abbrev0: + .section .debug_info,"",@progbits +.Ldebug_info0: + .section .debug_line,"",@progbits +.Ldebug_line0: + .text +.Ltext0: + .cfi_sections .debug_frame + .p2align 4,,15 +.globl g + .type g, @function +g: +.LFB0: + .file 1 "watch-notconst.c" + # watch-notconst.c:11 + .loc 1 11 0 + .cfi_startproc +.LVL0: + # basic block 2 + pushl %ebp + .cfi_def_cfa_offset 8 + movl %esp, %ebp + .cfi_offset 5, -8 + .cfi_def_cfa_register 5 + # watch-notconst.c:11 + .loc 1 11 0 + movl 8(%ebp), %eax + # watch-notconst.c:14 + .loc 1 14 0 + popl %ebp + .cfi_restore 5 + .cfi_def_cfa 4, 4 + # watch-notconst.c:11 + .loc 1 11 0 + addl $2, %eax + # watch-notconst.c:14 + .loc 1 14 0 + ret + .cfi_endproc +.LFE0: + .size g, .-g + .p2align 4,,15 +.globl main + .type main, @function +main: +.LFB1: + # watch-notconst.c:20 + .loc 1 20 0 + .cfi_startproc +.LVL1: + # basic block 2 + pushl %ebp + .cfi_def_cfa_offset 8 + movl %esp, %ebp + .cfi_offset 5, -8 + .cfi_def_cfa_register 5 + andl $-16, %esp + subl $16, %esp + # watch-notconst.c:21 + .loc 1 21 0 + movl $1, (%esp) + call f + # watch-notconst.c:23 + .loc 1 23 0 + xorl %eax, %eax + leave + .cfi_restore 5 + .cfi_def_cfa 4, 4 + ret + .cfi_endproc +.LFE1: + .size main, .-main +.Letext0: + .section .debug_info + .long 0xa3 # Length of Compilation Unit Info + .value 0x3 # DWARF version number + .long .Ldebug_abbrev0 # Offset Into Abbrev. Section + .byte 0x4 # Pointer Size (in bytes) + .uleb128 0x1 # (DIE (0xb) DW_TAG_compile_unit) + .long .LASF4 # DW_AT_producer: "GNU C 4.4.3 20100127 (Red Hat 4.4.3-4)" + .byte 0x1 # DW_AT_language + .long .LASF5 # DW_AT_name: "watch-notconst.c" + .long .LASF6 # DW_AT_comp_dir: "/home/sergio/work/src/git/gdb-src/gdb/testsuite/gdb.base" + .long .Ltext0 # DW_AT_low_pc + .long .Letext0 # DW_AT_high_pc + .long .Ldebug_line0 # DW_AT_stmt_list + .uleb128 0x2 # (DIE (0x25) DW_TAG_subprogram) + .byte 0x1 # DW_AT_external + .ascii "g\0" # DW_AT_name + .byte 0x1 # DW_AT_decl_file (watch-notconst.c) + .byte 0xa # DW_AT_decl_line + .byte 0x1 # DW_AT_prototyped + .long 0x54 # DW_AT_type + .long .LFB0 # DW_AT_low_pc + .long .LFE0 # DW_AT_high_pc + .byte 0x1 # DW_AT_frame_base + .byte 0x9c # DW_OP_call_frame_cfa + .long 0x54 # DW_AT_sibling + .uleb128 0x3 # (DIE (0x3e) DW_TAG_formal_parameter) + .ascii "j\0" # DW_AT_name + .byte 0x1 # DW_AT_decl_file (watch-notconst.c) + .byte 0xa # DW_AT_decl_line + .long 0x54 # DW_AT_type + .byte 0x2 # DW_AT_location + .byte 0x91 # DW_OP_fbreg + .sleb128 0 + .uleb128 0x4 # (DIE (0x4a) DW_TAG_variable) + .ascii "l\0" # DW_AT_name + .byte 0x1 # DW_AT_decl_file (watch-notconst.c) + .byte 0xc # DW_AT_decl_line + .long 0x54 # DW_AT_type + .byte 0x0 # end of children of DIE 0x25 + .uleb128 0x5 # (DIE (0x54) DW_TAG_base_type) + .byte 0x4 # DW_AT_byte_size + .byte 0x5 # DW_AT_encoding + .ascii "int\0" # DW_AT_name + .uleb128 0x6 # (DIE (0x5b) DW_TAG_subprogram) + .byte 0x1 # DW_AT_external + .long .LASF0 # DW_AT_name: "main" + .byte 0x1 # DW_AT_decl_file (watch-notconst.c) + .byte 0x13 # DW_AT_decl_line + .byte 0x1 # DW_AT_prototyped + .long 0x54 # DW_AT_type + .long .LFB1 # DW_AT_low_pc + .long .LFE1 # DW_AT_high_pc + .byte 0x1 # DW_AT_frame_base + .byte 0x9c # DW_OP_call_frame_cfa + .long 0x93 # DW_AT_sibling + .uleb128 0x7 # (DIE (0x76) DW_TAG_formal_parameter) + .long .LASF1 # DW_AT_name: "argc" + .byte 0x1 # DW_AT_decl_file (watch-notconst.c) + .byte 0x13 # DW_AT_decl_line + .long 0x54 # DW_AT_type + .byte 0x2 # DW_AT_location + .byte 0x91 # DW_OP_fbreg + .sleb128 0 + .uleb128 0x7 # (DIE (0x84) DW_TAG_formal_parameter) + .long .LASF2 # DW_AT_name: "argv" + .byte 0x1 # DW_AT_decl_file (watch-notconst.c) + .byte 0x13 # DW_AT_decl_line + .long 0x93 # DW_AT_type + .byte 0x2 # DW_AT_location + .byte 0x91 # DW_OP_fbreg + .sleb128 4 + .byte 0x0 # end of children of DIE 0x5b + .uleb128 0x8 # (DIE (0x93) DW_TAG_pointer_type) + .byte 0x4 # DW_AT_byte_size + .long 0x99 # DW_AT_type + .uleb128 0x8 # (DIE (0x99) DW_TAG_pointer_type) + .byte 0x4 # DW_AT_byte_size + .long 0x9f # DW_AT_type + .uleb128 0x9 # (DIE (0x9f) DW_TAG_base_type) + .byte 0x1 # DW_AT_byte_size + .byte 0x6 # DW_AT_encoding + .long .LASF3 # DW_AT_name: "char" + .byte 0x0 # end of children of DIE 0xb + .section .debug_abbrev + .uleb128 0x1 # (abbrev code) + .uleb128 0x11 # (TAG: DW_TAG_compile_unit) + .byte 0x1 # DW_children_yes + .uleb128 0x25 # (DW_AT_producer) + .uleb128 0xe # (DW_FORM_strp) + .uleb128 0x13 # (DW_AT_language) + .uleb128 0xb # (DW_FORM_data1) + .uleb128 0x3 # (DW_AT_name) + .uleb128 0xe # (DW_FORM_strp) + .uleb128 0x1b # (DW_AT_comp_dir) + .uleb128 0xe # (DW_FORM_strp) + .uleb128 0x11 # (DW_AT_low_pc) + .uleb128 0x1 # (DW_FORM_addr) + .uleb128 0x12 # (DW_AT_high_pc) + .uleb128 0x1 # (DW_FORM_addr) + .uleb128 0x10 # (DW_AT_stmt_list) + .uleb128 0x6 # (DW_FORM_data4) + .byte 0x0 + .byte 0x0 + .uleb128 0x2 # (abbrev code) + .uleb128 0x2e # (TAG: DW_TAG_subprogram) + .byte 0x1 # DW_children_yes + .uleb128 0x3f # (DW_AT_external) + .uleb128 0xc # (DW_FORM_flag) + .uleb128 0x3 # (DW_AT_name) + .uleb128 0x8 # (DW_FORM_string) + .uleb128 0x3a # (DW_AT_decl_file) + .uleb128 0xb # (DW_FORM_data1) + .uleb128 0x3b # (DW_AT_decl_line) + .uleb128 0xb # (DW_FORM_data1) + .uleb128 0x27 # (DW_AT_prototyped) + .uleb128 0xc # (DW_FORM_flag) + .uleb128 0x49 # (DW_AT_type) + .uleb128 0x13 # (DW_FORM_ref4) + .uleb128 0x11 # (DW_AT_low_pc) + .uleb128 0x1 # (DW_FORM_addr) + .uleb128 0x12 # (DW_AT_high_pc) + .uleb128 0x1 # (DW_FORM_addr) + .uleb128 0x40 # (DW_AT_frame_base) + .uleb128 0xa # (DW_FORM_block1) + .uleb128 0x1 # (DW_AT_sibling) + .uleb128 0x13 # (DW_FORM_ref4) + .byte 0x0 + .byte 0x0 + .uleb128 0x3 # (abbrev code) + .uleb128 0x5 # (TAG: DW_TAG_formal_parameter) + .byte 0x0 # DW_children_no + .uleb128 0x3 # (DW_AT_name) + .uleb128 0x8 # (DW_FORM_string) + .uleb128 0x3a # (DW_AT_decl_file) + .uleb128 0xb # (DW_FORM_data1) + .uleb128 0x3b # (DW_AT_decl_line) + .uleb128 0xb # (DW_FORM_data1) + .uleb128 0x49 # (DW_AT_type) + .uleb128 0x13 # (DW_FORM_ref4) + .uleb128 0x2 # (DW_AT_location) + .uleb128 0xa # (DW_FORM_block1) + .byte 0x0 + .byte 0x0 + .uleb128 0x4 # (abbrev code) + .uleb128 0x34 # (TAG: DW_TAG_variable) + .byte 0x0 # DW_children_no + .uleb128 0x3 # (DW_AT_name) + .uleb128 0x8 # (DW_FORM_string) + .uleb128 0x3a # (DW_AT_decl_file) + .uleb128 0xb # (DW_FORM_data1) + .uleb128 0x3b # (DW_AT_decl_line) + .uleb128 0xb # (DW_FORM_data1) + .uleb128 0x49 # (DW_AT_type) + .uleb128 0x13 # (DW_FORM_ref4) + .byte 0x0 + .byte 0x0 + .uleb128 0x5 # (abbrev code) + .uleb128 0x24 # (TAG: DW_TAG_base_type) + .byte 0x0 # DW_children_no + .uleb128 0xb # (DW_AT_byte_size) + .uleb128 0xb # (DW_FORM_data1) + .uleb128 0x3e # (DW_AT_encoding) + .uleb128 0xb # (DW_FORM_data1) + .uleb128 0x3 # (DW_AT_name) + .uleb128 0x8 # (DW_FORM_string) + .byte 0x0 + .byte 0x0 + .uleb128 0x6 # (abbrev code) + .uleb128 0x2e # (TAG: DW_TAG_subprogram) + .byte 0x1 # DW_children_yes + .uleb128 0x3f # (DW_AT_external) + .uleb128 0xc # (DW_FORM_flag) + .uleb128 0x3 # (DW_AT_name) + .uleb128 0xe # (DW_FORM_strp) + .uleb128 0x3a # (DW_AT_decl_file) + .uleb128 0xb # (DW_FORM_data1) + .uleb128 0x3b # (DW_AT_decl_line) + .uleb128 0xb # (DW_FORM_data1) + .uleb128 0x27 # (DW_AT_prototyped) + .uleb128 0xc # (DW_FORM_flag) + .uleb128 0x49 # (DW_AT_type) + .uleb128 0x13 # (DW_FORM_ref4) + .uleb128 0x11 # (DW_AT_low_pc) + .uleb128 0x1 # (DW_FORM_addr) + .uleb128 0x12 # (DW_AT_high_pc) + .uleb128 0x1 # (DW_FORM_addr) + .uleb128 0x40 # (DW_AT_frame_base) + .uleb128 0xa # (DW_FORM_block1) + .uleb128 0x1 # (DW_AT_sibling) + .uleb128 0x13 # (DW_FORM_ref4) + .byte 0x0 + .byte 0x0 + .uleb128 0x7 # (abbrev code) + .uleb128 0x5 # (TAG: DW_TAG_formal_parameter) + .byte 0x0 # DW_children_no + .uleb128 0x3 # (DW_AT_name) + .uleb128 0xe # (DW_FORM_strp) + .uleb128 0x3a # (DW_AT_decl_file) + .uleb128 0xb # (DW_FORM_data1) + .uleb128 0x3b # (DW_AT_decl_line) + .uleb128 0xb # (DW_FORM_data1) + .uleb128 0x49 # (DW_AT_type) + .uleb128 0x13 # (DW_FORM_ref4) + .uleb128 0x2 # (DW_AT_location) + .uleb128 0xa # (DW_FORM_block1) + .byte 0x0 + .byte 0x0 + .uleb128 0x8 # (abbrev code) + .uleb128 0xf # (TAG: DW_TAG_pointer_type) + .byte 0x0 # DW_children_no + .uleb128 0xb # (DW_AT_byte_size) + .uleb128 0xb # (DW_FORM_data1) + .uleb128 0x49 # (DW_AT_type) + .uleb128 0x13 # (DW_FORM_ref4) + .byte 0x0 + .byte 0x0 + .uleb128 0x9 # (abbrev code) + .uleb128 0x24 # (TAG: DW_TAG_base_type) + .byte 0x0 # DW_children_no + .uleb128 0xb # (DW_AT_byte_size) + .uleb128 0xb # (DW_FORM_data1) + .uleb128 0x3e # (DW_AT_encoding) + .uleb128 0xb # (DW_FORM_data1) + .uleb128 0x3 # (DW_AT_name) + .uleb128 0xe # (DW_FORM_strp) + .byte 0x0 + .byte 0x0 + .byte 0x0 + .section .debug_pubnames,"",@progbits + .long 0x1d # Length of Public Names Info + .value 0x2 # DWARF Version + .long .Ldebug_info0 # Offset of Compilation Unit Info + .long 0xa7 # Compilation Unit Length + .long 0x25 # DIE offset + .ascii "g\0" # external name + .long 0x5b # DIE offset + .ascii "main\0" # external name + .long 0x0 + .section .debug_aranges,"",@progbits + .long 0x1c # Length of Address Ranges Info + .value 0x2 # DWARF Version + .long .Ldebug_info0 # Offset of Compilation Unit Info + .byte 0x4 # Size of Address + .byte 0x0 # Size of Segment Descriptor + .value 0x0 # Pad to 8 byte boundary + .value 0x0 + .long .Ltext0 # Address + .long .Letext0-.Ltext0 # Length + .long 0x0 + .long 0x0 + .section .debug_str,"MS",@progbits,1 +.LASF2: + .string "argv" +.LASF5: + .string "watch-notconst.c" +.LASF4: + .string "GNU C 4.4.3 20100127 (Red Hat 4.4.3-4)" +.LASF6: + .string "/home/sergio/work/src/git/gdb-src/gdb/testsuite/gdb.base" +.LASF1: + .string "argc" +.LASF0: + .string "main" +.LASF3: + .string "char" + .ident "GCC: (GNU) 4.4.3 20100127 (Red Hat 4.4.3-4)" + .section .note.GNU-stack,"",@progbits diff --git a/gdb/testsuite/gdb.base/watch-notconst.c b/gdb/testsuite/gdb.base/watch-notconst.c new file mode 100644 index 0000000..621ca1e --- /dev/null +++ b/gdb/testsuite/gdb.base/watch-notconst.c @@ -0,0 +1,40 @@ +/* This testcase is part of GDB, the GNU debugger. + + Copyright 2010 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 . */ + +/* The original program corresponding to watch-notconst.S. + + This program is not compiled; the .S version is used instead. + + The purpose of this test is to see if GDB can still watch the + variable `x' even when we compile the program using -O2 + optimization. */ + +int +g (int j) +{ + int l = j + 2; + return l; +} + +extern int f (int i); + +int +main (int argc, char **argv) +{ + f (1); + return 0; +} diff --git a/gdb/testsuite/gdb.base/watch-notconst.exp b/gdb/testsuite/gdb.base/watch-notconst.exp new file mode 100644 index 0000000..fd9ee02 --- /dev/null +++ b/gdb/testsuite/gdb.base/watch-notconst.exp @@ -0,0 +1,42 @@ +# Copyright 2010 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 . + +set test "watch-notconst" + +if {![istarget *-*-linux*] + && ![istarget *-*-gnu*] + && ![istarget *-*-elf*] + && ![istarget *-*-openbsd*] + && ![istarget arm-*-eabi*] + && ![istarget powerpc-*-eabi*]} { + return 0 +} + +# This test can only be run on x86 targets. +if { ![istarget i?86-*] } { + return 0 +} + +if { [prepare_for_testing "${test}.exp" "${test}" \ + {watch-notconst.S watch-notconst2.S} {nodebug}] } { + return -1 +} + +if { ![runto f] } { + perror "Could not run to breakpoint `f'." + continue +} + +gdb_test "watch x" ".*\[Ww\]atchpoint 2: x" "watch x" diff --git a/gdb/testsuite/gdb.base/watch-notconst2.S b/gdb/testsuite/gdb.base/watch-notconst2.S new file mode 100644 index 0000000..a85fc2c --- /dev/null +++ b/gdb/testsuite/gdb.base/watch-notconst2.S @@ -0,0 +1,256 @@ +/* This testcase is part of GDB, the GNU debugger. + + Copyright 2010 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 . */ + +/* This source file was generated from watch-notconst2.c using the following + command line: + + gcc -m32 -dA -S -g -O2 watch-notconst2.c -o watch-notconst2.S + +*/ + + + .file "watch-notconst2.c" + .section .debug_abbrev,"",@progbits +.Ldebug_abbrev0: + .section .debug_info,"",@progbits +.Ldebug_info0: + .section .debug_line,"",@progbits +.Ldebug_line0: + .text +.Ltext0: + .cfi_sections .debug_frame + .p2align 4,,15 +.globl f + .type f, @function +f: +.LFB0: + .file 1 "watch-notconst2.c" + # watch-notconst2.c:13 + .loc 1 13 0 + .cfi_startproc +.LVL0: + # basic block 2 + pushl %ebp + .cfi_def_cfa_offset 8 + movl %esp, %ebp + .cfi_offset 5, -8 + .cfi_def_cfa_register 5 + pushl %ebx + subl $20, %esp + # watch-notconst2.c:13 + .loc 1 13 0 + movl 8(%ebp), %ebx + .cfi_offset 3, -12 + # watch-notconst2.c:15 + .loc 1 15 0 + movl $2, (%esp) + call g +.LVL1: + # watch-notconst2.c:17 + .loc 1 17 0 + movl %ebx, 8(%ebp) + # watch-notconst2.c:18 + .loc 1 18 0 + addl $20, %esp + popl %ebx + .cfi_restore 3 + popl %ebp + .cfi_restore 5 + .cfi_def_cfa 4, 4 +.LVL2: + # watch-notconst2.c:17 + .loc 1 17 0 + jmp g + .cfi_endproc +.LFE0: + .size f, .-f +.Letext0: + .section .debug_loc,"",@progbits +.Ldebug_loc0: +.LLST0: + .long .LVL0-.Ltext0 # Location list begin address (*.LLST0) + .long .LVL1-.Ltext0 # Location list end address (*.LLST0) + .value 0x2 # Location expression size + .byte 0x35 # DW_OP_lit5 + .byte 0x9f # DW_OP_stack_value + .long .LVL1-.Ltext0 # Location list begin address (*.LLST0) + .long .LVL2-.Ltext0 # Location list end address (*.LLST0) + .value 0x1 # Location expression size + .byte 0x53 # DW_OP_reg3 + .long 0x0 # Location list terminator begin (*.LLST0) + .long 0x0 # Location list terminator end (*.LLST0) + .section .debug_info + .long 0x5c # Length of Compilation Unit Info + .value 0x3 # DWARF version number + .long .Ldebug_abbrev0 # Offset Into Abbrev. Section + .byte 0x4 # Pointer Size (in bytes) + .uleb128 0x1 # (DIE (0xb) DW_TAG_compile_unit) + .long .LASF0 # DW_AT_producer: "GNU C 4.4.3 20100127 (Red Hat 4.4.3-4)" + .byte 0x1 # DW_AT_language + .long .LASF1 # DW_AT_name: "watch-notconst2.c" + .long .LASF2 # DW_AT_comp_dir: "/home/sergio/work/src/git/gdb-src/gdb/testsuite/gdb.base" + .long .Ltext0 # DW_AT_low_pc + .long .Letext0 # DW_AT_high_pc + .long .Ldebug_line0 # DW_AT_stmt_list + .uleb128 0x2 # (DIE (0x25) DW_TAG_subprogram) + .byte 0x1 # DW_AT_external + .ascii "f\0" # DW_AT_name + .byte 0x1 # DW_AT_decl_file (watch-notconst2.c) + .byte 0xc # DW_AT_decl_line + .byte 0x1 # DW_AT_prototyped + .long 0x58 # DW_AT_type + .long .LFB0 # DW_AT_low_pc + .long .LFE0 # DW_AT_high_pc + .byte 0x1 # DW_AT_frame_base + .byte 0x9c # DW_OP_call_frame_cfa + .long 0x58 # DW_AT_sibling + .uleb128 0x3 # (DIE (0x3e) DW_TAG_formal_parameter) + .ascii "i\0" # DW_AT_name + .byte 0x1 # DW_AT_decl_file (watch-notconst2.c) + .byte 0xc # DW_AT_decl_line + .long 0x58 # DW_AT_type + .byte 0x2 # DW_AT_location + .byte 0x91 # DW_OP_fbreg + .sleb128 0 + .uleb128 0x4 # (DIE (0x4a) DW_TAG_variable) + .ascii "x\0" # DW_AT_name + .byte 0x1 # DW_AT_decl_file (watch-notconst2.c) + .byte 0xe # DW_AT_decl_line + .long 0x58 # DW_AT_type + .long .LLST0 # DW_AT_location + .byte 0x0 # end of children of DIE 0x25 + .uleb128 0x5 # (DIE (0x58) DW_TAG_base_type) + .byte 0x4 # DW_AT_byte_size + .byte 0x5 # DW_AT_encoding + .ascii "int\0" # DW_AT_name + .byte 0x0 # end of children of DIE 0xb + .section .debug_abbrev + .uleb128 0x1 # (abbrev code) + .uleb128 0x11 # (TAG: DW_TAG_compile_unit) + .byte 0x1 # DW_children_yes + .uleb128 0x25 # (DW_AT_producer) + .uleb128 0xe # (DW_FORM_strp) + .uleb128 0x13 # (DW_AT_language) + .uleb128 0xb # (DW_FORM_data1) + .uleb128 0x3 # (DW_AT_name) + .uleb128 0xe # (DW_FORM_strp) + .uleb128 0x1b # (DW_AT_comp_dir) + .uleb128 0xe # (DW_FORM_strp) + .uleb128 0x11 # (DW_AT_low_pc) + .uleb128 0x1 # (DW_FORM_addr) + .uleb128 0x12 # (DW_AT_high_pc) + .uleb128 0x1 # (DW_FORM_addr) + .uleb128 0x10 # (DW_AT_stmt_list) + .uleb128 0x6 # (DW_FORM_data4) + .byte 0x0 + .byte 0x0 + .uleb128 0x2 # (abbrev code) + .uleb128 0x2e # (TAG: DW_TAG_subprogram) + .byte 0x1 # DW_children_yes + .uleb128 0x3f # (DW_AT_external) + .uleb128 0xc # (DW_FORM_flag) + .uleb128 0x3 # (DW_AT_name) + .uleb128 0x8 # (DW_FORM_string) + .uleb128 0x3a # (DW_AT_decl_file) + .uleb128 0xb # (DW_FORM_data1) + .uleb128 0x3b # (DW_AT_decl_line) + .uleb128 0xb # (DW_FORM_data1) + .uleb128 0x27 # (DW_AT_prototyped) + .uleb128 0xc # (DW_FORM_flag) + .uleb128 0x49 # (DW_AT_type) + .uleb128 0x13 # (DW_FORM_ref4) + .uleb128 0x11 # (DW_AT_low_pc) + .uleb128 0x1 # (DW_FORM_addr) + .uleb128 0x12 # (DW_AT_high_pc) + .uleb128 0x1 # (DW_FORM_addr) + .uleb128 0x40 # (DW_AT_frame_base) + .uleb128 0xa # (DW_FORM_block1) + .uleb128 0x1 # (DW_AT_sibling) + .uleb128 0x13 # (DW_FORM_ref4) + .byte 0x0 + .byte 0x0 + .uleb128 0x3 # (abbrev code) + .uleb128 0x5 # (TAG: DW_TAG_formal_parameter) + .byte 0x0 # DW_children_no + .uleb128 0x3 # (DW_AT_name) + .uleb128 0x8 # (DW_FORM_string) + .uleb128 0x3a # (DW_AT_decl_file) + .uleb128 0xb # (DW_FORM_data1) + .uleb128 0x3b # (DW_AT_decl_line) + .uleb128 0xb # (DW_FORM_data1) + .uleb128 0x49 # (DW_AT_type) + .uleb128 0x13 # (DW_FORM_ref4) + .uleb128 0x2 # (DW_AT_location) + .uleb128 0xa # (DW_FORM_block1) + .byte 0x0 + .byte 0x0 + .uleb128 0x4 # (abbrev code) + .uleb128 0x34 # (TAG: DW_TAG_variable) + .byte 0x0 # DW_children_no + .uleb128 0x3 # (DW_AT_name) + .uleb128 0x8 # (DW_FORM_string) + .uleb128 0x3a # (DW_AT_decl_file) + .uleb128 0xb # (DW_FORM_data1) + .uleb128 0x3b # (DW_AT_decl_line) + .uleb128 0xb # (DW_FORM_data1) + .uleb128 0x49 # (DW_AT_type) + .uleb128 0x13 # (DW_FORM_ref4) + .uleb128 0x2 # (DW_AT_location) + .uleb128 0x6 # (DW_FORM_data4) + .byte 0x0 + .byte 0x0 + .uleb128 0x5 # (abbrev code) + .uleb128 0x24 # (TAG: DW_TAG_base_type) + .byte 0x0 # DW_children_no + .uleb128 0xb # (DW_AT_byte_size) + .uleb128 0xb # (DW_FORM_data1) + .uleb128 0x3e # (DW_AT_encoding) + .uleb128 0xb # (DW_FORM_data1) + .uleb128 0x3 # (DW_AT_name) + .uleb128 0x8 # (DW_FORM_string) + .byte 0x0 + .byte 0x0 + .byte 0x0 + .section .debug_pubnames,"",@progbits + .long 0x14 # Length of Public Names Info + .value 0x2 # DWARF Version + .long .Ldebug_info0 # Offset of Compilation Unit Info + .long 0x60 # Compilation Unit Length + .long 0x25 # DIE offset + .ascii "f\0" # external name + .long 0x0 + .section .debug_aranges,"",@progbits + .long 0x1c # Length of Address Ranges Info + .value 0x2 # DWARF Version + .long .Ldebug_info0 # Offset of Compilation Unit Info + .byte 0x4 # Size of Address + .byte 0x0 # Size of Segment Descriptor + .value 0x0 # Pad to 8 byte boundary + .value 0x0 + .long .Ltext0 # Address + .long .Letext0-.Ltext0 # Length + .long 0x0 + .long 0x0 + .section .debug_str,"MS",@progbits,1 +.LASF1: + .string "watch-notconst2.c" +.LASF2: + .string "/home/sergio/work/src/git/gdb-src/gdb/testsuite/gdb.base" +.LASF0: + .string "GNU C 4.4.3 20100127 (Red Hat 4.4.3-4)" + .ident "GCC: (GNU) 4.4.3 20100127 (Red Hat 4.4.3-4)" + .section .note.GNU-stack,"",@progbits diff --git a/gdb/testsuite/gdb.base/watch-notconst2.c b/gdb/testsuite/gdb.base/watch-notconst2.c new file mode 100644 index 0000000..4a70f8d --- /dev/null +++ b/gdb/testsuite/gdb.base/watch-notconst2.c @@ -0,0 +1,35 @@ +/* This testcase is part of GDB, the GNU debugger. + + Copyright 2010 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 . */ + +/* The original program corresponding to watch-notconst2.S. + + This program is not compiled; the .S version is used instead. + + The purpose of this test is to see if GDB can still watch the + variable `x' even when we compile the program using -O2 + optimization. */ + +extern int g (int j); + +int +f (int i) +{ + int x = 5; + g (2); + x = i; + return g (x); +} diff --git a/gdb/testsuite/gdb.base/watchpoint.c b/gdb/testsuite/gdb.base/watchpoint.c index 9275d88..8c212c1 100644 --- a/gdb/testsuite/gdb.base/watchpoint.c +++ b/gdb/testsuite/gdb.base/watchpoint.c @@ -40,6 +40,7 @@ struct foo struct1, struct2, *ptr1, *ptr2; int doread = 0; char *global_ptr; +char **global_ptr_ptr; void marker1 () { @@ -119,6 +120,10 @@ func4 () buf[0] = 3; global_ptr = buf; buf[0] = 7; + buf[1] = 5; + global_ptr_ptr = &global_ptr; + buf[0] = 9; + global_ptr++; } int main () diff --git a/gdb/testsuite/gdb.base/watchpoint.exp b/gdb/testsuite/gdb.base/watchpoint.exp index b53faef..c7d5c6b 100644 --- a/gdb/testsuite/gdb.base/watchpoint.exp +++ b/gdb/testsuite/gdb.base/watchpoint.exp @@ -635,7 +635,21 @@ proc test_watchpoint_and_breakpoint {} { } } } - + +proc test_constant_watchpoint {} { + global gdb_prompt + + gdb_test "watch 5" "Cannot watch constant value 5." "number is constant" + gdb_test "watch marker1" "Cannot watch constant value marker1." \ + "marker1 is constant" + gdb_test "watch count + 6" ".*atchpoint \[0-9\]+: count \\+ 6" + gdb_test "set \$expr_breakpoint_number = \$bpnum" "" + gdb_test "delete \$expr_breakpoint_number" "" + gdb_test "watch 7 + count" ".*atchpoint \[0-9\]+: 7 \\+ count" + gdb_test "set \$expr_breakpoint_number = \$bpnum" "" + gdb_test "delete \$expr_breakpoint_number" "" +} + proc test_inaccessible_watchpoint {} { global gdb_prompt @@ -656,7 +670,8 @@ proc test_inaccessible_watchpoint {} { } gdb_test "watch *global_ptr" ".*atchpoint \[0-9\]+: \\*global_ptr" - gdb_test "next" ".*global_ptr = buf.*" + gdb_test "set \$global_ptr_breakpoint_number = \$bpnum" "" + gdb_test "next" ".*global_ptr = buf.*" "global_ptr next" gdb_test_multiple "next" "next over ptr init" { -re ".*atchpoint \[0-9\]+: \\*global_ptr\r\n\r\nOld value = .*\r\nNew value = 3 .*\r\n.*$gdb_prompt $" { # We can not test for here because NULL may be readable. @@ -669,6 +684,28 @@ proc test_inaccessible_watchpoint {} { pass "next over buffer set" } } + gdb_test "delete \$global_ptr_breakpoint_number" "" + gdb_test "watch **global_ptr_ptr" ".*atchpoint \[0-9\]+: \\*\\*global_ptr_ptr" + gdb_test "set \$global_ptr_ptr_breakpoint_number = \$bpnum" "" + gdb_test "next" ".*global_ptr_ptr = &global_ptr.*" "gloabl_ptr_ptr next" + gdb_test_multiple "next" "next over global_ptr_ptr init" { + -re ".*atchpoint \[0-9\]+: \\*\\*global_ptr_ptr\r\n\r\nOld value = .*\r\nNew value = 7 .*\r\n.*$gdb_prompt $" { + # We can not test for here because NULL may be readable. + # This test does rely on *NULL != 7. + pass "next over global_ptr_ptr init" + } + } + gdb_test_multiple "next" "next over global_ptr_ptr buffer set" { + -re ".*atchpoint \[0-9\]+: \\*\\*global_ptr_ptr\r\n\r\nOld value = 7 .*\r\nNew value = 9 .*\r\n.*$gdb_prompt $" { + pass "next over global_ptr_ptr buffer set" + } + } + gdb_test_multiple "next" "next over global_ptr_ptr pointer advance" { + -re ".*atchpoint \[0-9\]+: \\*\\*global_ptr_ptr\r\n\r\nOld value = 9 .*\r\nNew value = 5 .*\r\n.*$gdb_prompt $" { + pass "next over global_ptr_ptr pointer advance" + } + } + gdb_test "delete \$global_ptr_ptr_breakpoint_number" "" } } @@ -845,6 +882,17 @@ if [initialize] then { test_watchpoint_and_breakpoint test_watchpoint_in_big_blob + + # See above. + if [istarget "mips-idt-*"] then { + gdb_exit + gdb_start + gdb_reinitialize_dir $srcdir/$subdir + gdb_load $binfile + initialize + } + + test_constant_watchpoint } # Restore old timeout