; RUN: llc < %s -march=avr | FileCheck %s target triple = "avr-unknown-unknown" ; The case illustrate DAG schedular may pre-schedule the node has ; ADJCALLSTACKDOWN parent, so ADJCALLSTACKUP may hold CallResource too long ; and make other calls can't be scheduled. If there's no other available node ; to schedule, the scheduler will try to rename the register by creating the ; copy to avoid the conflict which will fail because CallResource is not a real ; physical register. ; ; The issue is found by Tim on https://github.com/avr-rust/rust/issues/111 and ; discuss in http://lists.llvm.org/pipermail/llvm-dev/2018-October/127083.html. define void @"main"() addrspace(1) { start: %0 = or i64 undef, undef br i1 undef, label %mul_and_call, label %fail mul_and_call: %1 = mul i64 %0, %0 call addrspace(1) void @"three_ints"(i64 undef, i64 %1, i64 %0) ; The CHECK line only want to make sure the following assertion message ; won't trigger due to create copy of artificial CallResource register. ; llc: llvm/lib/CodeGen/TargetRegisterInfo.cpp:203: const llvm::TargetRegisterClass* llvm::TargetRegisterInfo::getMinimalPhysRegClass(unsigned int, llvm::MVT) const: Assertion `BestRC && "Couldn't find the register class"' failed. ; CHECK: call __muldi3 ret void fail: ret void } declare void @"three_ints"(i64, i64, i64) addrspace(1)