[llvm] [DebugInfo] Emit negative DW_AT_bit_offset in explicit signed form (PR #87994)

[Artem Belevich via llvm-commits]

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@@ -16,7 +16,7 @@
 ; CHECK-NEXT: .b8 1    // DW_AT_byte_size
 ; CHECK-NEXT: .b8 6    // DW_AT_bit_size
 ; Negative offset must be encoded as an unsigned integer.
-; CHECK-NEXT: .b64 0xffffffffffffffff // DW_AT_bit_offset
+; CHECK-NEXT: .b8 127  // DW_AT_bit_offset
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Artem-B wrote:

127  (0x7f) does not look like a negative number. Do we really expect to see 127 as representation of some *negative* value?

https://github.com/llvm/llvm-project/pull/87994