[LLDB] Fix for D139955 Summary:

[ayermolo]

Summary

Fixing a small typo.

[clayborg]

Is there no test case catching this?

[ayermolo]

added test

[ayermolo]

updated test

[clayborg]

Fix the error message to check for the exact error message and this is good to go.

lldb/test/Shell/SymbolFile/DWARF/range-lower-then-low-pc.s

10 ↗

(On Diff #507528)

might be good to verify that the correct DIE offset of the block ID is. in the error message. If this code hadn't assert'ed we still might have gotten a string output, but we need to verify the data is correct. If you run it manually once you can see the exact error message we will need to check for.

[ayermolo]

updated test

[clayborg]

lldb/test/Shell/SymbolFile/DWARF/range-lower-then-low-pc.s

11 ↗

(On Diff #507812)

Shouldn't the low PC of the function be zero?

[clayborg]

FYI: This might be because we are using a .o file and relocations are being applied internally!?

lldb/test/Shell/SymbolFile/DWARF/range-lower-then-low-pc.s

11 ↗

(On Diff #507812)

0x00000043:   DW_TAG_subprogram
                DW_AT_low_pc	(0x0000000000000001)
                DW_AT_high_pc	(0x000000000000002e)
                DW_AT_frame_base	(DW_OP_reg6 RBP)
                DW_AT_linkage_name	("_ZL3foob")
                DW_AT_name	("foo")
                DW_AT_decl_file	("base-lower-then-range-entry/base-lower-then-range-entry/main.cpp")
                DW_AT_decl_line	(1)
                DW_AT_type	(0x0000008b)

0x00000060:     DW_TAG_formal_parameter
                  DW_AT_location	(DW_OP_fbreg -5)
                  DW_AT_name	("b")
                  DW_AT_decl_file	("base-lower-then-range-entry/base-lower-then-range-entry/main.cpp")
                  DW_AT_decl_line	(1)
                  DW_AT_type	(0x00000092)

0x0000006e:     DW_TAG_lexical_block
                  DW_AT_ranges	(0x00000000
                     [0x0000000000000000, 0x000000000000001f)
                     [0x0000000000000000, 0x000000000000002d))

Seems like we have a bug in the code that prints the error message?

[ayermolo]

lldb/test/Shell/SymbolFile/DWARF/range-lower-then-low-pc.s

11 ↗

(On Diff #507812)

Stepped through the code 0x21 is what gets extracted in DWARFDebugInfoEntry::GetDIENamesAndRanges.

[clayborg]

Must be relocations causing the stuff to not match up to the llvm-dwarfdump output.

[ayermolo]

In D146659#4217557, @clayborg wrote:

Must be relocations causing the stuff to not match up to the llvm-dwarfdump output.

Looked through llvm-dwarfdump code. Yep. since relocation exists, it just returns an addend which is 1.

[ayermolo]

fixed up refs

lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp

case DW_TAG_lexical_block: {
         for (size_t i = 0; i < num_ranges; ++i) {
           const DWARFRangeList::Entry &range = ranges.GetEntryRef(i);
           const addr_t range_base = range.GetRangeBase();
           if (range_base >= subprogram_low_pc)
             block->AddRange(Block::Range(range_base - subprogram_low_pc,
                                          range.GetByteSize()));
           else {
             GetObjectFile()->GetModule()->ReportError(
-                "{0x:+8}: adding range [{1:x16}-{2:x16}) which has a base "
+                "{0:x8}: adding range [{1:x16}-{2:x16}) which has a base "
                 "that is less than the function's low PC {3:x16}. Please file "
                 "a bug and attach the file at the "
                 "start of this error message",
                 block->GetID(), range_base, range.GetRangeEnd(),
                 subprogram_low_pc);
           }
         }
         block->FinalizeRanges();