1; RUN: llc < %s -mtriple=avr | FileCheck %s 2 3; The avr-rust bug can be found here: 4; https://github.com/avr-rust/rust/issues/112 5; 6; In this test, the codegen stage generates a FRMIDX 7; instruction. Later in the pipeline, the frame index 8; gets expanded into a 16-bit MOVWRdRr instruction. 9; 10; There was a bug in the FRMIDX->MOVWRdRr expansion logic 11; that could leave the MOVW instruction with an extraneous 12; operand, left over from the original FRMIDX. 13; 14; This would trigger an assertion: 15; 16; Assertion failed: ((isImpReg || Op.isRegMask() || MCID->isVariadic() || 17; OpNo < MCID->getNumOperands() || isMetaDataOp) && 18; "Trying to add an operand to a machine instr that is already done!"), 19; function addOperand, file llvm/lib/CodeGen/MachineInstr.cpp 20; 21; The logic has since been fixed. 22 23; CHECK-LABEL: "core::str::slice_error_fail" 24define void @"core::str::slice_error_fail"(i16 %arg) personality ptr addrspace(1) @rust_eh_personality { 25start: 26 %char_range = alloca { i16, i16 }, align 1 27 br i1 undef, label %"<core::option::Option<T>>::unwrap.exit.thread", label %bb11.i.i 28 29"<core::option::Option<T>>::unwrap.exit.thread": 30 br label %"core::char::methods::<impl char>::len_utf8.exit" 31 32bb11.i.i: 33 %tmp = bitcast ptr %char_range to ptr 34 %tmp1 = icmp ult i32 undef, 65536 35 %..i = select i1 %tmp1, i16 3, i16 4 36 br label %"core::char::methods::<impl char>::len_utf8.exit" 37 38"core::char::methods::<impl char>::len_utf8.exit": 39 %tmp2 = phi ptr [ %tmp, %bb11.i.i ], [ undef, %"<core::option::Option<T>>::unwrap.exit.thread" ] 40 %_0.0.i12 = phi i16 [ %..i, %bb11.i.i ], [ 1, %"<core::option::Option<T>>::unwrap.exit.thread" ] 41 %tmp3 = add i16 %_0.0.i12, %arg 42 store i16 %tmp3, ptr undef, align 1 43 store ptr %tmp2, ptr undef, align 1 44 unreachable 45} 46 47declare i32 @rust_eh_personality(...) addrspace(1) 48 49