From e8369a73b982f60326e89c38bd1a7e6bb7363beb Mon Sep 17 00:00:00 2001 From: Andrew Burgess Date: Fri, 18 Oct 2013 16:25:14 +0000 Subject: [PATCH] Hardware watchpoints turned off, inferior not yet started. https://sourceware.org/ml/gdb-patches/2013-10/msg00477.html gdb/ChangeLog * breakpoint.c (update_watchpoint): If hardware watchpoints are forced off, downgrade them to software watchpoints if possible, and error out if not possible. (watch_command_1): Move watchpoint type selection closer to watchpoint creation, and extend the comments. gdb/testsuite/ChangeLog * gdb.base/watchpoints.exp: Add test for setting software watchpoints of different types before starting the inferior. --- gdb/ChangeLog | 8 ++++++++ gdb/breakpoint.c | 28 +++++++++++++++++++--------- gdb/testsuite/ChangeLog | 5 +++++ gdb/testsuite/gdb.base/watchpoints.exp | 23 +++++++++++++++++++++++ 4 files changed, 55 insertions(+), 9 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index c3e3d21..30829f5 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,11 @@ +2013-10-18 Andrew Burgess + + * breakpoint.c (update_watchpoint): If hardware watchpoints are + forced off, downgrade them to software watchpoints if possible, + and error out if not possible. + (watch_command_1): Move watchpoint type selection closer to + watchpoint creation, and extend the comments. + 2013-10-18 Pedro Alves PR gdb/16062 diff --git a/gdb/breakpoint.c b/gdb/breakpoint.c index 5ce50de..c630b87 100644 --- a/gdb/breakpoint.c +++ b/gdb/breakpoint.c @@ -1795,11 +1795,18 @@ update_watchpoint (struct watchpoint *b, int reparse) don't try to insert watchpoint. We don't automatically delete such watchpoint, though, since failure to parse expression is different from out-of-scope watchpoint. */ - if ( !target_has_execution) + if (!target_has_execution) { /* Without execution, memory can't change. No use to try and set watchpoint locations. The watchpoint will be reset when the target gains execution, through breakpoint_re_set. */ + if (!can_use_hw_watchpoints) + { + if (b->base.ops->works_in_software_mode (&b->base)) + b->base.type = bp_watchpoint; + else + error (_("Software read/access watchpoints not supported.")); + } } else if (within_current_scope && b->exp) { @@ -11081,13 +11088,6 @@ watch_command_1 (const char *arg, int accessflag, int from_tty, if (*tok) error (_("Junk at end of command.")); - if (accessflag == hw_read) - bp_type = bp_read_watchpoint; - else if (accessflag == hw_access) - bp_type = bp_access_watchpoint; - else - bp_type = bp_hardware_watchpoint; - frame = block_innermost_frame (exp_valid_block); /* If the expression is "local", then set up a "watchpoint scope" @@ -11124,7 +11124,17 @@ watch_command_1 (const char *arg, int accessflag, int from_tty, } } - /* Now set up the breakpoint. */ + /* Now set up the breakpoint. We create all watchpoints as hardware + watchpoints here even if hardware watchpoints are turned off, a call + to update_watchpoint later in this function will cause the type to + drop back to bp_watchpoint (software watchpoint) if required. */ + + if (accessflag == hw_read) + bp_type = bp_read_watchpoint; + else if (accessflag == hw_access) + bp_type = bp_access_watchpoint; + else + bp_type = bp_hardware_watchpoint; w = XCNEW (struct watchpoint); b = &w->base; diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog index 8e057f6..60c1295 100644 --- a/gdb/testsuite/ChangeLog +++ b/gdb/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2013-10-18 Andrew Burgess + + * gdb.base/watchpoints.exp: Add test for setting software + watchpoints of different types before starting the inferior. + 2013-10-18 Pedro Alves PR gdb/16062 diff --git a/gdb/testsuite/gdb.base/watchpoints.exp b/gdb/testsuite/gdb.base/watchpoints.exp index 7c10d81..b70e86c 100644 --- a/gdb/testsuite/gdb.base/watchpoints.exp +++ b/gdb/testsuite/gdb.base/watchpoints.exp @@ -29,6 +29,29 @@ if {[prepare_for_testing $testfile.exp $testfile $srcfile debug]} { return -1 } +with_test_prefix "before inferior start" { + # Ensure that if we turn off hardware watchpoints and set a watch point + # before starting the inferior the watchpoint created will not be a + # hardware watchpoint. + gdb_test_no_output "set can-use-hw-watchpoints 0" "" + gdb_test "watch ival1" "Watchpoint \[0-9\]+: ival1" \ + "create watchpoint" + + # The next tests are written to match the current state of gdb: access + # and read watchpoints require hardware watchpoint support, with this + # turned off these can't be created. + gdb_test "awatch ival1" \ + "Software read/access watchpoints not supported." \ + "create access watchpoint" + gdb_test "rwatch ival1" \ + "Software read/access watchpoints not supported." \ + "create read watchpoint" +} + + # This will turn hardware watchpoints back on and delete the watchpoint + # we just created. + clean_restart ${binfile} + # Disable hardware watchpoints if necessary. if [target_info exists gdb,no_hardware_watchpoints] { gdb_test_no_output "set can-use-hw-watchpoints 0" "" -- 2.7.4