lldb/test/API/tools/lldb-dap/optimized/TestDAP_optimized.py

"""
Test lldb-dap variables/stackTrace request for optimized code
"""

from lldbsuite.test.decorators import *
from lldbsuite.test.lldbtest import line_number
from lldbsuite.test.tools.lldb_dap import DAPTestCaseBase, ExpectVar
from lldbsuite.test.tools.lldb_dap.types import LaunchArgs


class TestDAP_optimized(DAPTestCaseBase):
    def test_stack_frame_name(self):
        """Test optimized frame has special name suffix."""
        program = self.getBuildArtifact("a.out")
        session = self.build_and_create_session()

        source = "main.cpp"
        breakpoint_line = line_number(source, "// breakpoint 1")
        with session.configure(LaunchArgs(program)) as ctx:
            bp_ids = session.resolve_source_breakpoints(source, [breakpoint_line])

        stop_event = session.verify_stopped_on_breakpoint(
            bp_ids, after=ctx.process_event
        )
        frames = session.thread_context_from(stop_event).frames()

        leaf_frame = frames[0].frame
        self.assertTrue(leaf_frame.name.endswith(" [opt]"))
        parent_frame = frames[1].frame
        self.assertTrue(parent_frame.name.endswith(" [opt]"))

    @skipIfAsan  # On ASAN builds this test intermittently fails https://github.com/llvm/llvm-project/issues/111061
    @skipIfWasm  # an optimized out variable keeps a reused local, so reading it succeeds
    def test_optimized_variable(self):
        """Test optimized variable value contains error."""
        program = self.getBuildArtifact("a.out")
        session = self.build_and_create_session()
        source = "main.cpp"
        breakpoint_line = line_number(source, "// breakpoint 2")
        with session.configure(LaunchArgs(program)) as ctx:
            bp_ids = session.resolve_source_breakpoints(source, [breakpoint_line])

        stop_event = session.verify_stopped_on_breakpoint(
            bp_ids, after=ctx.process_event
        )
        optimized_variable = session.top_frame_from(stop_event).locals["argc"]
        value = optimized_variable.value

        self.assertTrue(
            value.startswith("<error:"), f"expect error for value: '{value}'"
        )
        self.assertTrue(
            ("could not evaluate DW_OP_entry_value: no parent function" in value)
            or ("variable not available" in value),
            f"{value=}",
        )
        session.continue_to_exit()

    @skipIfWindows
    @skipIfWasm  # a wasm local always lives in a writable slot
    def test_constant_variable_is_read_only(self):
        """A variable without writable storage is hinted as read-only."""
        program = self.getBuildArtifact("a.out")
        session = self.build_and_create_session()
        source = "main.cpp"
        breakpoint_line = line_number(source, "// breakpoint 3")
        with session.configure(LaunchArgs(program)) as ctx:
            bp_ids = session.resolve_source_breakpoints(source, [breakpoint_line])

        stop_event = session.verify_stopped_on_breakpoint(
            bp_ids, after=ctx.process_event
        )
        # At -O3 `k` is folded into a constant with no storage.
        k = session.top_frame_from(stop_event).locals["k"]
        session.verify_variable(
            k.variable, ExpectVar(type="int", value="42", read_only=True)
        )
        session.continue_to_exit()