MI support for '-var-create $regname' command.

[ki.stfu]

Summary

This command is currently processed using expression evaluation, meaning the variable binds to the result of the expression not the register.
Therefore any subsequent calls to '-var-assign' will not update the register. Fixed by detecting '$' prefix for registers according to specification.

Thanks, Ewan

Patch from [e-mail]

[ki.stfu]

Add a test case for this please (see test/tools/lldb-mi/variable/TestMiVar.py)

[EwanCrawford]

Added test case to TestMiVar.py

[ki.stfu]

Looks good apart a few minor changes that I can fix by myself. Should I commit it for you?

test/tools/lldb-mi/variable/TestMiVar.py

212 ↗

(On Diff #23852)

Use str.split there

tools/lldb-mi/MICmdCmdVar.cpp

182 ↗

(On Diff #23852)

Add spacing

[EwanCrawford]

Yes please, thanks again.

[ki.stfu]

Rebase against ToT

[ki.stfu]

Fix a few remarks after review

[labath]

This test is failing on Linux i386.

http://lab.llvm.org:8011/builders/lldb-x86_64-ubuntu-14.04-cmake/builds/1755

======================================================================
ERROR: test_lldbmi_var_create_register (TestMiVar.MiVarTestCase)
   Test that 'lldb-mi --interpreter' works for -var-create $regname.
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/lldb-buildbot/lldbSlave/buildWorkingDir/llvm/tools/lldb/test/lldbtest.py", line 447, in wrapper
    return func(self, *args, **kwargs)
  File "/lldb-buildbot/lldbSlave/buildWorkingDir/llvm/tools/lldb/test/lldbtest.py", line 562, in wrapper
    func(*args, **kwargs)
  File "/lldb-buildbot/lldbSlave/buildWorkingDir/llvm/tools/lldb/test/tools/lldb-mi/variable/TestMiVar.py", line 215, in test_lldbmi_var_create_register
    self.expect("\^done,name=\"var_reg\",numchild=\"0\",value=\"0x[0-9a-f]+\",type=\"unsigned long\",thread-id=\"1\",has_more=\"0\"")
  File "/lldb-buildbot/lldbSlave/buildWorkingDir/llvm/tools/lldb/test/tools/lldb-mi/lldbmi_testcase.py", line 46, in expect
    return self.child.expect(pattern, *args, **kwargs)
  File "/lldb-buildbot/lldbSlave/buildWorkingDir/llvm/tools/lldb/test/pexpect-2.4/pexpect.py", line 1316, in expect
    return self.expect_list(compiled_pattern_list, timeout, searchwindowsize)
  File "/lldb-buildbot/lldbSlave/buildWorkingDir/llvm/tools/lldb/test/pexpect-2.4/pexpect.py", line 1330, in expect_list
    return self.expect_loop(searcher_re(pattern_list), timeout, searchwindowsize)
  File "/lldb-buildbot/lldbSlave/buildWorkingDir/llvm/tools/lldb/test/pexpect-2.4/pexpect.py", line 1414, in expect_loop
    raise TIMEOUT (str(e) + '\n' + str(self))
TIMEOUT: Timeout exceeded in read_nonblocking().

Could you fix/revert/XFAIL, please?

[ki.stfu]

Oops.. done:
$ svn ci
Sending test/tools/lldb-mi/variable/TestMiVar.py
Transmitting file data .
Committed revision 235197.

Thanks,
Ilia

[EwanCrawford]

Test looks like it still fails, need to change
self.expect("\^done,value=\"0x0000000000000006\"")
to self.expect("\^done,value=\"0x00000006\"") for 32 bit.

Best,

Ewan

lldb/trunk/test/tools/lldb-mi/variable/TestMiVar.py

def test_lldbmi_var_update(self):
         self.runCmd("-exec-continue")
         self.expect("\^running")
         self.expect("\*stopped,reason=\"breakpoint-hit\"")
 
         # Test that var_complex_array was updated
         self.runCmd("-var-update --all-values var_complx_array")
         self.expect("\^done,changelist=\[\{name=\"var_complx_array\",value=\"\[2\]\",in_scope=\"true\",type_changed=\"false\",has_more=\"0\"\}\]")
 
+    @lldbmi_test
+    @expectedFailureWindows("llvm.org/pr22274: need a pexpect replacement for windows")
+    @skipIfFreeBSD # llvm.org/pr22411: Failure presumably due to known thread races
+    def test_lldbmi_var_create_register(self):
+        """Test that 'lldb-mi --interpreter' works for -var-create $regname."""
+
+        self.spawnLldbMi(args = None)
+
+        # Load executable
+        self.runCmd("-file-exec-and-symbols %s" % self.myexe)
+        self.expect("\^done")
+
+        # Run to main
+        self.runCmd("-break-insert -f main")
+        self.expect("\^done,bkpt={number=\"1\"")
+        self.runCmd("-exec-run")
+        self.expect("\^running")
+        self.expect("\*stopped,reason=\"breakpoint-hit\"")
+
+        # Find name of register 0
+        self.runCmd("-data-list-register-names 0")
+        self.expect("\^done,register-names=\[\".+?\"\]")
+        register_name = self.child.after.split("\"")[1]
+
+        # Create variable for register 0
+        self.runCmd("-var-create var_reg * $%s" % register_name)
+        self.expect("\^done,name=\"var_reg\",numchild=\"0\",value=\"0x[0-9a-f]+\",type=\"unsigned long\",thread-id=\"1\",has_more=\"0\"")
+
+        # Assign value to variable
+        self.runCmd("-var-assign var_reg \"6\"")
+        self.expect("\^done,value=\"0x0000000000000006\"")
+
+        # Assert register 0 updated
+        self.runCmd("-data-list-register-values d 0")
+        self.expect("\^done,register-values=\[{number=\"0\",value=\"6\"")
+
 if __name__ == '__main__':
     unittest2.main()

lldb/trunk/tools/lldb-mi/MICmdCmdVar.cpp

CMICmdCmdVarCreate::Execute(void)
     const CMIUtilString &rStrExpression(pArgExpression->GetValue());
     m_strExpression = rStrExpression;
 
     CMICmnLLDBDebugSessionInfo &rSessionInfo(CMICmnLLDBDebugSessionInfo::Instance());
     lldb::SBProcess sbProcess = rSessionInfo.GetProcess();
     lldb::SBThread thread = (nThreadId != UINT64_MAX) ? sbProcess.GetThreadByIndexID(nThreadId) : sbProcess.GetSelectedThread();
     m_nThreadId = thread.GetIndexID();
     lldb::SBFrame frame = bCurrentFrame ? thread.GetSelectedFrame() : thread.GetFrameAtIndex(nFrame);
+    lldb::SBValue value;
 
+    if (rStrExpression[0] == '$')
+    {
+        const CMIUtilString rStrRegister(rStrExpression.substr(1).c_str());
+        value = frame.FindRegister(rStrRegister.c_str());
+    }
+    else
+    {
         const bool bArgs = true;
         const bool bLocals = true;
         const bool bStatics = true;
         const bool bInScopeOnly = false;
         const lldb::SBValueList valueList = frame.GetVariables(bArgs, bLocals, bStatics, bInScopeOnly);
-    lldb::SBValue value = valueList.GetFirstValueByName(rStrExpression.c_str());
+        value = valueList.GetFirstValueByName(rStrExpression.c_str());
+    }
+
     if (!value.IsValid())
         value = frame.EvaluateExpression(rStrExpression.c_str());
 
     if (value.IsValid())
     {
         CompleteSBValue(value);
         m_bValid = true;
         m_nChildren = value.GetNumChildren();