LLVM assembler and Jump tables

Code Generation X86
1

Hello,
I’m not quite sure this is the correct forum, but was looking for some help on how to implement something in assembly that will compile with LLVM on windows.
I have the following jump table defined in a MASM file that I’m trying to port over to AT&T syntax so that I can do some things in llvm-mc passes with the program:

$L_140025138           DWORD IMAGEREL $L_140003492
          DWORD IMAGEREL $L_14000348b
          DWORD IMAGEREL $L_14000347d
          DWORD IMAGEREL $L_14000346f
          DWORD IMAGEREL $L_140003461
          DWORD IMAGEREL $L_140003453
          DWORD IMAGEREL $L_140003445
          DWORD IMAGEREL $L_140003437
          DWORD IMAGEREL $L_140003429

Converting to AT&T syntax I believe it should look like this:

.L_140025138:
          .long .L_140003492-__ImageBase
          .long .L_14000348b-__ImageBase
          .long .L_14000347d-__ImageBase
          .long .L_14000346f-__ImageBase
          .long .L_140003461-__ImageBase
          .long .L_140003453-__ImageBase
          .long .L_140003445-__ImageBase
          .long .L_140003437-__ImageBase
          .long .L_140003429-__ImageBase

When compiling with clang-cl, it produces errors such as

error: symbol '__ImageBase' can not be undefined in a subtraction expression
          .long .L_140003429-__ImageBase

I wrote some assembly to print out the __ImageBase of the executable, so I know it is resolving it during link/runtime, but I’m kind of at loss as to how to handle it as a calculation for the label. Any pointers would be greatly appreciated.

2

I think you want something like .rva .L_140003492.

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