LLC always has a tab?

I’m building a target for the intermediate language of another compiler. The other intermediate language is close to an assembly language (RTL, 1 operation per line), so I based my target off of the Mips target. However, the intermediate language i’m targetting does not support tabs before the instructions. I’ve looked through the files and found that the tab comes from the printInstruction() method, which is generated when compiling.

Directly after all of the tables it generates, it produces this line:
O << “\t”;

(O is the output stream)

Since its in the generated code, I’ve been looking through the .td files, but haven’t had any luck. How can I prevent this tab from being generated?

I forgot to mention, the generated file that has the tab is


I’ve always been bothered by this tab character that doesn’t come from the target. The line you’re looking for I believe is from /utils/TableGen/AsmWriterEmitter.cpp at line 428. In my opinion the target should control whether a prefix is printed before an instruction.



If anyone is looking for a solution to this that doesn’t involve changing TableGen, here’s what I did for now:

I overrode the rule to make this file with My own, which is basically a copy of theirs. I changed it to be more specific so that it would always override, and then I added two lines to remove it from the include file before the make process continues.

$(ObjDir)/ : $(ObjDir)/.dir $(LLVM_TBLGEN)
$(Echo) “Building $(<F) assembly writer with tblgen”
$(Verb) $(LLVMTableGen) -gen-asm-writer -o $(call SYSPATH, $@) $<
grep -v ‘O << “\t”’ $(call SYSPATH, $@) >$(call SYSPATH, $@).temp
cp $(call SYSPATH, $@).temp $(call SYSPATH, $@)

To test it, make sure you change a related .td file so that the rule is executed.