Adding a New Instruction to LLVM IR

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1

Hello;

I was planning to add a new instruction to the LLVM IR (and later to MIPS backend) for TLS(Thread level speculation) support. For this I tried to follow the steps described in http://llvm.org/docs/ExtendingLLVM dot html#instruction.

But I could not find any llvm/lib/AsmParser/Lexer.l and llvm/lib/AsmParser/llvmAsmParser.y file in both the svn repository and the source code downloaded from the website. Could you tell me what are the files that need to be modified to add a new token to parse my instruction from assembly text file (STEP 4) and add the grammar on how my instruction can be read and what it will construct as a result (STEP 5).

Thanks;

2

Side note: TLS = Thread Local Storage. You’ll need a different acronym in the LLVM context to avoid really confusing people.

-Jim

3

Arnamoy,

Can you explain the semantics of this instruction? I also have hardware
that supports speculative execution, and we might be able to
collaborate [this may apply to others as well]?

-Hal

4

The relevant code is still in lib/AsmParser/; it's just that we've
swtiched from a generated lexer/parser to a hand-written one. If you
want examples, try looking in the revision history for my atomics
work.

-Eli