From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 81433 invoked by alias); 20 Jun 2016 15:32:00 -0000 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 Received: (qmail 81414 invoked by uid 89); 20 Jun 2016 15:31:59 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-1.8 required=5.0 tests=AWL,BAYES_00,RCVD_IN_DNSWL_NONE,SPF_PASS autolearn=ham version=3.3.2 spammy=rewritten, Thus, succeed, 6087 X-HELO: relay1.mentorg.com Received: from relay1.mentorg.com (HELO relay1.mentorg.com) (192.94.38.131) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with (AES256-GCM-SHA384 encrypted) ESMTPS; Mon, 20 Jun 2016 15:31:49 +0000 Received: from svr-orw-fem-03.mgc.mentorg.com ([147.34.97.39]) by relay1.mentorg.com with esmtp id 1bF1Ax-00070G-6R from Don_Breazeal@mentor.com ; Mon, 20 Jun 2016 08:31:47 -0700 Received: from [172.30.1.26] (147.34.91.1) by SVR-ORW-FEM-03.mgc.mentorg.com (147.34.97.39) with Microsoft SMTP Server (TLS) id 14.3.224.2; Mon, 20 Jun 2016 08:31:46 -0700 Subject: [PING] [PATCH v2] Fix -var-update for registers in frames 1 and up To: , References: <1465854882-42527-1-git-send-email-donb@codesourcery.com> From: Don Breazeal Message-ID: <57680C62.5060807@codesourcery.com> Date: Mon, 20 Jun 2016 15:32:00 -0000 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.7.2 MIME-Version: 1.0 In-Reply-To: <1465854882-42527-1-git-send-email-donb@codesourcery.com> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit X-IsSubscribed: yes X-SW-Source: 2016-06/txt/msg00331.txt.bz2 On 6/13/2016 2:54 PM, Don Breazeal wrote: > This is an updated version of a patch to fix access to registers > for frames other than the current frame via var-update. The piece > of the patch affecting GDB proper has been completely re-written. > It changes the initialization of varobj->root->frame in varobj_create > so that existing mechanisms (with minimal changes) select the correct > frame and provide correct register values from -var-update. > > In addition, the new test for this functionality has been expanded > to cover an analogous case using floating variable objects, and > several tests have been updated to account for the fact that with > the new initialization, -var-create and -var-list-children now > provide a thread-id field where previously they didn't. > > Thanks > --Don > > ------------ > This patch fixes a problem with using the MI -var-update command > to access the values of registers in frames other than the current > frame. The patch includes a test that demonstrates the problem: > > * run so there are several frames on the stack > * create a fixed varobj for $pc in each frame, #'s 1 and above > * step one instruction, to modify the value of $pc > * call -var-update for each of the previously created varobjs > to verify that they are not reported as having changed. > > Without the patch, the -var-update command reported that $pc for all > frames 1 and above had changed to the value of $pc in frame 0. > > When a varobj is created by -var-create, varobj->root->frame should > be set to specified frame. Then for a subsequent -var-update, > varobj.c:check_scope can use varobj->root->frame to select the > right frame based on the type of varobj. > > The problem is that for register expressions varobj->root->frame is not > set correctly. This frame tracking is done using the global > 'innermost_block' which is set in the various parser files (for example > c-exp.y). However, this is not set for register expressions. > > The fix is to change the initialization of innermost_block in > varobj_create from NULL to the global block, as returned by > block_global_block. Then varobj_create sets varobj->root->frame > for register varobjs, and value_of_root_1 can check for the > global block when determining whether the variable is in-scope > and select the frame appropriately. > > A side-effect of this change is that for register varobjs and some > global variable varobjs, the output of -var-create now includes the > thread-id field. The rationale for this is as follow: if we ask for a > particular expression in a particular frame, that implies a particular > thread. Thus including the thread-id is correct behavior, and the > test results have been updated accordingly. > > In addition there is a new test, gdb.mi/mi-frame-regs.exp, which > performs the test described in the bullet list above as well as a > similar test using a floating variable object to represent $pc. > > We attempted a couple alternative solutions: > * a special case in varobj_update to select the frame was not ideal > because it didn't use the existing mechanisms to select the frame. > * setting innermost_block in write_dollar_variable had side-effects > in the CLI that would have required special case code. > > Tested on x86_64 Linux native, no regressions. > > gdb/testsuite/ChangeLog: > 2016-06-13 Don Breazeal > > * gdb.ada/mi_interface.exp: Add thread-id field to expected > output of -var-create and -var-list-children. > * gdb.ada/mi_var_array.exp: Add thread-id field to expected > output of -var-list-children. > * gdb.mi/mi-break.exp (test_error): Add thread-id field to > expected output of -var-create. > * gdb.mi/mi-frame-regs.exp: New test script. > * gdb.mi/mi-var-cmd.exp: Add thread-id field to expected > output of -var-create. > * gdb.mi/mi-var-create-rtti.exp: Likewise. > > gdb/ChangeLog: > 2016-06-13 Don Breazeal > Andrew Burgess > > * varobj.c (varobj_create): Initialize innermost_block to > the global block instead of NULL. > (new_root_variable): Initialize the thread_id and next > fields. > (value_of_root_1): Set within_scope if the variable's > valid_block field is the global block. > > --- > gdb/testsuite/gdb.ada/mi_interface.exp | 4 +- > gdb/testsuite/gdb.ada/mi_var_array.exp | 2 +- > gdb/testsuite/gdb.mi/mi-break.exp | 2 +- > gdb/testsuite/gdb.mi/mi-frame-regs.exp | 183 ++++++++++++++++++++++++++++ > gdb/testsuite/gdb.mi/mi-var-cmd.exp | 4 +- > gdb/testsuite/gdb.mi/mi-var-create-rtti.exp | 2 +- > gdb/varobj.c | 8 +- > 7 files changed, 196 insertions(+), 9 deletions(-) > > diff --git a/gdb/testsuite/gdb.ada/mi_interface.exp b/gdb/testsuite/gdb.ada/mi_interface.exp > index 6000ec8..b948cd5 100644 > --- a/gdb/testsuite/gdb.ada/mi_interface.exp > +++ b/gdb/testsuite/gdb.ada/mi_interface.exp > @@ -44,9 +44,9 @@ mi_continue_to_line \ > "stop at start of main Ada procedure" > > mi_gdb_test "-var-create ggg1 * ggg1" \ > - "\\^done,name=\"ggg1\",numchild=\"1\",value=\"{...}\",type=\" pck.gadatatype\",has_more=\"0\"" \ > + "\\^done,name=\"ggg1\",numchild=\"1\",value=\"{...}\",type=\" pck.gadatatype\",thread-id=\"1\",has_more=\"0\"" \ > "Create ggg1 varobj" > > mi_gdb_test "-var-list-children 1 ggg1" \ > - "\\^done,numchild=\"1\",children=\\\[child={name=\"ggg1.i\",exp=\"i\",numchild=\"0\",value=\"42\",type=\"integer\"}\\\],has_more=\"0\"" \ > + "\\^done,numchild=\"1\",children=\\\[child={name=\"ggg1.i\",exp=\"i\",numchild=\"0\",value=\"42\",type=\"integer\",thread-id=\"1\"}\\\],has_more=\"0\"" \ > "list ggg1's children" > diff --git a/gdb/testsuite/gdb.ada/mi_var_array.exp b/gdb/testsuite/gdb.ada/mi_var_array.exp > index c648e7e..c02d4c9 100644 > --- a/gdb/testsuite/gdb.ada/mi_var_array.exp > +++ b/gdb/testsuite/gdb.ada/mi_var_array.exp > @@ -48,5 +48,5 @@ mi_gdb_test "-var-create vta * vta" \ > "Create bt varobj" > > mi_gdb_test "-var-list-children vta" \ > - "\\^done,numchild=\"2\",children=\\\[child={name=\"vta.n\",exp=\"n\",numchild=\"0\",type=\"bar\\.int\"},child={name=\"vta.f\",exp=\"f\",numchild=\"0\",type=\"array \\(1 .. n\\) of character\"}\\\],.*" \ > + "\\^done,numchild=\"2\",children=\\\[child={name=\"vta.n\",exp=\"n\",numchild=\"0\",type=\"bar\\.int\",thread-id=\"1\"},child={name=\"vta.f\",exp=\"f\",numchild=\"0\",type=\"array \\(1 .. n\\) of character\",thread-id=\"1\"}\\\],.*" \ > "list vta's children" > diff --git a/gdb/testsuite/gdb.mi/mi-break.exp b/gdb/testsuite/gdb.mi/mi-break.exp > index 85f328d..bdd43e0 100644 > --- a/gdb/testsuite/gdb.mi/mi-break.exp > +++ b/gdb/testsuite/gdb.mi/mi-break.exp > @@ -213,7 +213,7 @@ proc test_error {} { > # containing function call, the internal breakpoint created to handle > # function call would be reported, messing up MI output. > mi_gdb_test "-var-create V * return_1()" \ > - "\\^done,name=\"V\",numchild=\"0\",value=\"1\",type=\"int\",has_more=\"0\"" \ > + "\\^done,name=\"V\",numchild=\"0\",value=\"1\",type=\"int\",thread-id=\"1\",has_more=\"0\"" \ > "create varobj for function call" > > mi_gdb_test "-var-update *" \ > diff --git a/gdb/testsuite/gdb.mi/mi-frame-regs.exp b/gdb/testsuite/gdb.mi/mi-frame-regs.exp > new file mode 100644 > index 0000000..45f81d6 > --- /dev/null > +++ b/gdb/testsuite/gdb.mi/mi-frame-regs.exp > @@ -0,0 +1,183 @@ > +# Copyright 1999-2016 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 . > + > +# Test essential Machine interface (MI) operations > +# > +# Verify that -var-update will provide the correct values for floating > +# and fixed varobjs that represent the pc register. > +# > + > +load_lib mi-support.exp > +set MIFLAGS "-i=mi" > + > +standard_testfile basics.c > + > +if {[gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" \ > + executable {debug}] != "" } then { > + untested mi-frame-regs.exp > + return -1 > +} > + > +# Return the address of the specified breakpoint. > + > +proc breakpoint_address {bpnum} { > + global hex > + global expect_out > + global mi_gdb_prompt > + > + send_gdb "info breakpoint $bpnum\n" > + gdb_expect { > + -re ".*($hex).*$mi_gdb_prompt$" { > + return $expect_out(1,string) > + } > + -re ".*$mi_gdb_prompt$" { > + return "" > + } > + timeout { > + return "" > + } > + } > +} > + > +# Test that a floating varobj representing $pc will provide the > +# correct value via -var-update as the program stops at > +# breakpoints in different functions. > + > +proc do_floating_varobj_test {} { > + global srcfile > + global hex > + global expect_out > + > + gdb_exit > + if {[mi_gdb_start]} then { > + continue > + } > + > + with_test_prefix "floating" { > + mi_run_to_main > + > + # Create a floating varobj for $pc. > + mi_gdb_test "-var-create --thread 1 --frame 0 - @ \$pc" \ > + "\\^done,.*value=\"$hex.*" \ > + "create varobj for pc in frame 0" > + > + set nframes 4 > + for {set i 1} {$i < $nframes} {incr i} { > + > + # Run to a breakpoint in each callee function in succession. > + # Note that we can't use mi_runto because we need the > + # breakpoint to be persistent, so we can use its address. > + set bpnum [expr $i + 1] > + mi_create_breakpoint \ > + "basics.c:callee$i" \ > + "insert breakpoint at basics.c:callee$i" \ > + -number $bpnum -func callee$i -file ".*basics.c" > + > + mi_execute_to "exec-continue" "breakpoint-hit" \ > + "callee$i" ".*" ".*${srcfile}" ".*" \ > + { "" "disp=\"keep\"" } "breakpoint hit" > + > + # Get the value of $pc from the floating varobj. > + mi_gdb_test "-var-update 1 var1" \ > + "\\^done,.*value=\"($hex) .*" \ > + "-var-update for frame $i" > + set pcval $expect_out(3,string) > + > + # Get the address of the current breakpoint. > + set bpaddr [breakpoint_address $bpnum] > + if {$bpaddr == ""} then { > + unresolved "get address of breakpoint $bpnum" > + return > + } > + > + # Check that the addresses are the same. > + if {[expr $bpaddr != $pcval]} then { > + fail "\$pc does not equal address of breakpoint" > + } else { > + pass "\$pc equals address of breakpoint" > + } > + } > + } > +} > + > +# Create a varobj for the pc register in each of the frames other > +# than frame 0. > + > +proc var_create_regs {nframes} { > + global hex > + > + for {set i 1} {$i < $nframes} {incr i} { > + mi_gdb_test "-var-create --thread 1 --frame $i - \* \$pc" \ > + "\\^done,.*value=\"$hex.*" \ > + "create varobj for pc in frame $i" > + } > +} > + > +# Check that -var-update reports that the value of the pc register > +# for each of the frames 1 and above is reported as unchanged. > + > +proc var_update_regs {nframes} { > + > + for {set i 1} {$i < $nframes} {incr i} { > + mi_gdb_test "-var-update 1 var$i" \ > + "\\^done,(changelist=\\\[\\\])" \ > + "pc unchanged in -var-update for frame $i" > + } > +} > + > +# Test that fixed varobjs representing $pc in different stack frames > +# will provide the correct value via -var-update after the program > +# counter changes (without substantially changing the stack). > + > +proc do_fixed_varobj_test {} { > + global srcfile > + > + gdb_exit > + if {[mi_gdb_start]} then { > + continue > + } > + > + with_test_prefix "fixed" { > + mi_run_to_main > + > + # Run to the function 'callee3' so we have several frames. > + mi_create_breakpoint "basics.c:callee3" \ > + "insert breakpoint at basics.c:callee3" \ > + -number 2 -func callee3 -file ".*basics.c" > + > + mi_execute_to "exec-continue" "breakpoint-hit" \ > + "callee3" ".*" ".*${srcfile}" ".*" \ > + { "" "disp=\"keep\"" } "breakpoint hit" > + > + # At the breakpoint in callee3 there are 4 frames. Create a > + # varobj for the pc in each of frames 1 and above. > + set nframes 4 > + var_create_regs $nframes > + > + # Step one instruction to change the program counter. > + mi_execute_to "exec-next-instruction" "end-stepping-range" \ > + "callee3" ".*" ".*${srcfile}" ".*" "" \ > + "next instruction in callee3" > + > + # Check that -var-update reports that the values are unchanged. > + var_update_regs $nframes > + } > +} > + > +do_fixed_varobj_test > +do_floating_varobj_test > + > +mi_gdb_exit > +return 0 > diff --git a/gdb/testsuite/gdb.mi/mi-var-cmd.exp b/gdb/testsuite/gdb.mi/mi-var-cmd.exp > index 558cd6c..68e3cf8 100644 > --- a/gdb/testsuite/gdb.mi/mi-var-cmd.exp > +++ b/gdb/testsuite/gdb.mi/mi-var-cmd.exp > @@ -381,7 +381,7 @@ mi_gdb_test "-var-update *" \ > "assign same value to func (update)" > > mi_gdb_test "-var-create array_ptr * array_ptr" \ > - "\\^done,name=\"array_ptr\",numchild=\"1\",value=\"$hex \",type=\"int \\*\",has_more=\"0\"" \ > + "\\^done,name=\"array_ptr\",numchild=\"1\",value=\"$hex \",type=\"int \\*\",thread-id=\"1\",has_more=\"0\"" \ > "create global variable array_ptr" > > mi_gdb_test "-var-assign array_ptr array2" \ > @@ -608,7 +608,7 @@ mi_check_varobj_value F 7 "check F inside callee" > # A varobj we fail to read during -var-update should be considered > # out of scope. > mi_gdb_test "-var-create null_ptr * **0" \ > - {\^done,name="null_ptr",numchild="0",value=".*",type="int",has_more="0"} \ > + {\^done,name="null_ptr",numchild="0",value=".*",type="int",thread-id="1"has_more="0"} \ > "create null_ptr" > > # Allow this to succeed, if address zero is readable, although it > diff --git a/gdb/testsuite/gdb.mi/mi-var-create-rtti.exp b/gdb/testsuite/gdb.mi/mi-var-create-rtti.exp > index 3bcb36c..a8cc76f 100644 > --- a/gdb/testsuite/gdb.mi/mi-var-create-rtti.exp > +++ b/gdb/testsuite/gdb.mi/mi-var-create-rtti.exp > @@ -49,6 +49,6 @@ mi_gdb_test "-gdb-set print object on" ".*" > # We use a explicit cast to (void *) as that is the > # type that caused the bug this testcase is testing for. > mi_gdb_test "-var-create sp1 * ((void*)\$sp)" \ > - "\\^done,name=\"sp1\",numchild=\"0\",value=\"$hex\",type=\"void \\*\",has_more=\"0\"" \ > + "\\^done,name=\"sp1\",numchild=\"0\",value=\"$hex\",type=\"void \\*\",thread-id=\"1\",has_more=\"0\"" \ > "-var-create sp1 * \$sp" > gdb_exit > diff --git a/gdb/varobj.c b/gdb/varobj.c > index 6f56cba..1e3f192 100644 > --- a/gdb/varobj.c > +++ b/gdb/varobj.c > @@ -323,7 +323,7 @@ varobj_create (char *objname, > } > > p = expression; > - innermost_block = NULL; > + innermost_block = block_global_block (block); > /* Wrap the call to parse expression, so we can > return a sensible error. */ > TRY > @@ -2103,6 +2103,8 @@ new_root_variable (void) > var->root->floating = 0; > var->root->rootvar = NULL; > var->root->is_valid = 1; > + var->root->thread_id = 0; > + var->root->next = NULL; > > return var; > } > @@ -2268,7 +2270,9 @@ value_of_root_1 (struct varobj **var_handle) > back_to = make_cleanup_restore_current_thread (); > > /* Determine whether the variable is still around. */ > - if (var->root->valid_block == NULL || var->root->floating) > + if (var->root->valid_block == NULL > + || BLOCK_SUPERBLOCK (var->root->valid_block) == NULL > + || var->root->floating) > within_scope = 1; > else if (var->root->thread_id == 0) > { >