[Lldb-commits] [PATCH] D79491: [lldb] Revive TestBasicEntryValuesX86_64

[Vedant Kumar via Phabricator via lldb-commits]

vsk added a comment.

Thanks for working on this!



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Comment at: lldb/test/API/functionalities/param_entry_vals/basic_entry_values_x86_64/main.cpp:21-22
+  ++global;
   //% self.filecheck("image lookup -va $pc", "main.cpp", "-check-prefix=FUNC1-DESC")
   // FUNC1-DESC: name = "sink", type = "int &", location = DW_OP_entry_value(DW_OP_reg5 RDI)
 }
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labath wrote:
> If we remove this check, the test will be completely architecture- and abi-independent. I don't think this check is particularly useful (we use llvm to print the dwarf expression, and there are better ways to test the image lookup command). Maybe we could just keep it to ensure that we really are evaluating entry values, but change the check the just search for the DW_OP_entry_value keyword (and then run the test on all architectures)?
We should stop matching %rdi, as the purpose of the check is just to determine whether we really are testing entry value evaluation. However, llvm doesn't support entry value production for all platforms, so we would need to restrict the test to {x86_64, arm, aarch64} (still a clear improvement over the current situation).


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Comment at: lldb/test/API/functionalities/param_entry_vals/basic_entry_values_x86_64/main.cpp:34
+  // FUNC2-EXPR1: ${{.*}} = 123
+  // FUNC2-EXPR2: ${{.*}} = 2
 }
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Hm, I thought inline tests only supported running one command per breakpoint. Have you tried running this test with `--param dotest-args='-t'` to verify that FUNC2-EXPR2 gets matched? If it does, that's great; if not, we can manufacture a second breakpoint by adding another '++global' or convert this to an API test.


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Comment at: lldb/test/API/functionalities/param_entry_vals/basic_entry_values_x86_64/main.cpp:56
+  //%     expect_cmd_failure=True)
+  // FUNC4-EXPR-FAIL: couldn't get the value of variable x: Could not evaluate DW_OP_entry_value.
+  // FUNC4-EXPR: couldn't get the value of variable sink:
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Ditto, I have the same concern about whether 'expr sink' is evaluated.


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Comment at: lldb/test/API/functionalities/param_entry_vals/basic_entry_values_x86_64/main.cpp:61-62
-
-  //% self.filecheck("expr x", "main.cpp", "-check-prefix=FUNC2-EXPR-FAIL", expect_cmd_failure=True)
-  // FUNC2-EXPR-FAIL: couldn't get the value of variable x: variable not available
-
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labath wrote:
> I'm not sure why this was previously expected to fail -- I don't see a reason why the compiler couldn't emit an entry value for `x` now, or before this patch. And in the new setup, the expression actually succeeds.
IIRC this is left over from when entry value propagation in LiveDebugValues was being reworked.


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D79491/new/

https://reviews.llvm.org/D79491