search for: savecalleesavedregist

...u either violate the ABI for callee, or you're restricted to do tail call lowering only for internal functions, making all stuff inpractical. . Only call-clobbered registers can be used to store pointer to callee (I'd suggest %ecx on x86/32, btw). > Or do i have to insert code into PEI::saveCalleeSavedRegisters to > detect that there is a tail called function that uses a callee saved > register and move it to another (EAX). You shouldn't use call-saved registers at all. Only call-clobbered. It seems, that you can use the trick similar to eh_return lowering (that case is somehow special, b...

...ed addl $44, %esp jmp *%esi # TAIL CALL jmpr Is there a way to indicate that the register the tail call instruction uses as destination needs to be valid after the callee saved registers have been restored? (some X86InstrInfo.td foo magic maybe ?) Or do i have to insert code into PEI::saveCalleeSavedRegisters to detect that there is a tail called function that uses a callee saved register and move it to another (EAX). that's how the TAILJMP instruction looks: let isCall = 1, isTerminator = 1, isReturn = 1, isBarrier = 1, noResults = 1 in def TAILJMPr : I<0xFF, MRM4r, (ops GR32:$dst),...

...n llvm-2.0 the epilogue inserter ignoring the isTerminator instruction - note to myself: should move to trunk soon!) another option would be to do the move from the register holding the function pointer to a register like ECX myself (as you say), >> Or do i have to insert code into PEI::saveCalleeSavedRegisters to >> detect that there is a tail called function that uses a callee saved >> register and move it to another (EAX). > You shouldn't use call-saved registers at all. Only call-clobbered. It > seems, that you can use the trick similar to eh_return lowering (that > case is...

...rter ignoring > the isTerminator instruction - note to myself: should move to trunk > soon!) > > another option would be to do the move from the register holding the > function pointer to a register like ECX myself (as you say), > >>> Or do i have to insert code into PEI::saveCalleeSavedRegisters to >>> detect that there is a tail called function that uses a callee saved >>> register and move it to another (EAX). >> You shouldn't use call-saved registers at all. Only call-clobbered. >> It >> seems, that you can use the trick similar to eh_return...