search for: checkearlytargetmatchpredicate

Hi Daniel, I defined checkEarlyTargetMatchPredicate() to explicitly check for the tied operands, and it worked. I could define an alias like: InstAlias<"oldOP $rd, $rd, $rs1", (NEWOP $rd, $rs1)> However, I had to additionally change AsmMatcherEmitter 'Hack' variable setting to allow the repeated operand $rd in the AsmStr...

Hi, On Instructions you can use checkEarlyTargetMatchPredicate() to check that the operands are the same. There's an example of that in MipsAsmParser.cpp for DATI and DAHI. I can't think of a reason TableGen couldn't be made to allow this for InstAlias too. > On 15 Dec 2017, at 02:12, via llvm-dev <llvm-dev at lists.llvm.org> wrote: >...

Hello, InstAlias does not allow tied operands (repeated operands) in the asm string to be matched. It seems this situation is explicitly prevented in AsmMatcherEmitter.cpp: if (!Hack) PrintFatalError(TheDef->getLoc(), "ERROR: matchable with tied operand '" + Tok + "' can never be matched!");