teak-llvm/lldb/packages/Python/lldbsuite/test/python_api/watchpoint/TestSetWatchpoint.py
Ulrich Weigand bb00d0b6b2 Support Linux on SystemZ as platform
This patch adds support for Linux on SystemZ:
- A new ArchSpec value of eCore_s390x_generic
- A new directory Plugins/ABI/SysV-s390x providing an ABI implementation
- Register context support
- Native Linux support including watchpoint support
- ELF core file support
- Misc. support throughout the code base (e.g. breakpoint opcodes)
- Test case updates to support the platform

This should provide complete support for debugging the SystemZ platform.
Not yet supported are optional features like transaction support (zEC12)
or SIMD vector support (z13).

There is no instruction emulation, since our ABI requires that all code
provide correct DWARF CFI at all PC locations in .eh_frame to support
unwinding (i.e. -fasynchronous-unwind-tables is on by default).

The implementation follows existing platforms in a mostly straightforward
manner.  A couple of things that are different:

- We do not use PTRACE_PEEKUSER / PTRACE_POKEUSER to access single registers,
  since some registers (access register) reside at offsets in the user area
  that are multiples of 4, but the PTRACE_PEEKUSER interface only allows
  accessing aligned 8-byte blocks in the user area.  Instead, we use a s390
  specific ptrace interface PTRACE_PEEKUSR_AREA / PTRACE_POKEUSR_AREA that
  allows accessing a whole block of the user area in one go, so in effect
  allowing to treat parts of the user area as register sets.

- SystemZ hardware does not provide any means to implement read watchpoints,
  only write watchpoints.  In fact, we can only support a *single* write
  watchpoint (but this can span a range of arbitrary size).  In LLDB this
  means we support only a single watchpoint.  I've set all test cases that
  require read watchpoints (or multiple watchpoints) to expected failure
  on the platform.  [ Note that there were two test cases that install
  a read/write watchpoint even though they nowhere rely on the "read"
  property.  I've changed those to simply use plain write watchpoints. ]

Differential Revision: http://reviews.llvm.org/D18978

llvm-svn: 266308
2016-04-14 14:28:34 +00:00

96 lines
3.5 KiB
Python

"""
Use lldb Python SBValue API to create a watchpoint for read_write of 'globl' var.
"""
from __future__ import print_function
import os, time
import re
import lldb
from lldbsuite.test.decorators import *
from lldbsuite.test.lldbtest import *
from lldbsuite.test import lldbutil
class SetWatchpointAPITestCase(TestBase):
mydir = TestBase.compute_mydir(__file__)
def setUp(self):
# Call super's setUp().
TestBase.setUp(self)
# Our simple source filename.
self.source = 'main.c'
# Find the line number to break inside main().
self.line = line_number(self.source, '// Set break point at this line.')
@add_test_categories(['pyapi'])
@expectedFailureAndroid(archs=['arm', 'aarch64']) # Watchpoints not supported
@expectedFailureAll(oslist=["windows"], bugnumber="llvm.org/pr24446: WINDOWS XFAIL TRIAGE - Watchpoints not supported on Windows")
@expectedFailureAll(archs=['s390x']) # Read-write watchpoints not supported on SystemZ
def test_watch_val(self):
"""Exercise SBValue.Watch() API to set a watchpoint."""
self.build()
exe = os.path.join(os.getcwd(), "a.out")
# Create a target by the debugger.
target = self.dbg.CreateTarget(exe)
self.assertTrue(target, VALID_TARGET)
# Now create a breakpoint on main.c.
breakpoint = target.BreakpointCreateByLocation(self.source, self.line)
self.assertTrue(breakpoint and
breakpoint.GetNumLocations() == 1,
VALID_BREAKPOINT)
# Now launch the process, and do not stop at the entry point.
process = target.LaunchSimple (None, None, self.get_process_working_directory())
# We should be stopped due to the breakpoint. Get frame #0.
process = target.GetProcess()
self.assertTrue(process.GetState() == lldb.eStateStopped,
PROCESS_STOPPED)
thread = lldbutil.get_stopped_thread(process, lldb.eStopReasonBreakpoint)
frame0 = thread.GetFrameAtIndex(0)
# Watch 'global' for read and write.
value = frame0.FindValue('global', lldb.eValueTypeVariableGlobal)
error = lldb.SBError();
watchpoint = value.Watch(True, True, True, error)
self.assertTrue(value and watchpoint,
"Successfully found the variable and set a watchpoint")
self.DebugSBValue(value)
# Hide stdout if not running with '-t' option.
if not self.TraceOn():
self.HideStdout()
print(watchpoint)
# Continue. Expect the program to stop due to the variable being written to.
process.Continue()
if (self.TraceOn()):
lldbutil.print_stacktraces(process)
thread = lldbutil.get_stopped_thread(process, lldb.eStopReasonWatchpoint)
self.assertTrue(thread, "The thread stopped due to watchpoint")
self.DebugSBValue(value)
# Continue. Expect the program to stop due to the variable being read from.
process.Continue()
if (self.TraceOn()):
lldbutil.print_stacktraces(process)
thread = lldbutil.get_stopped_thread(process, lldb.eStopReasonWatchpoint)
self.assertTrue(thread, "The thread stopped due to watchpoint")
self.DebugSBValue(value)
# Continue the process. We don't expect the program to be stopped again.
process.Continue()
# At this point, the inferior process should have exited.
self.assertTrue(process.GetState() == lldb.eStateExited, PROCESS_EXITED)