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

[Paul T Robinson 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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pogo59 wrote:

I believe DW_FORM_sdata encodes its value as a signed LEB128, so this is a one-byte encoding of -1.

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