1 ; RUN: llc < %s -mtriple=x86_64-darwin -mcpu=generic | FileCheck %s 2 ; XFAIL: * 3 ; rdar:15661073 simple example of redundant adds 4 ; 5 ; MachineCSE should coalesce trivial subregister copies. 6 ; 7 ; The extra movl+addl should be removed during MachineCSE. 8 ; CHECK-LABEL: redundantadd 9 ; CHECK: cmpq 10 ; CHECK: movq 11 ; CHECK-NOT: movl 12 ; CHECK: addl 13 ; CHECK-NOT: addl 14 ; CHECK: ret 15 16 define i64 @redundantadd(i64* %a0, i64* %a1) { 17 entry: 18 %tmp8 = load i64, i64* %a0, align 8 19 %tmp12 = load i64, i64* %a1, align 8 20 %tmp13 = icmp ult i64 %tmp12, -281474976710656 21 br i1 %tmp13, label %exit1, label %body 22 23 exit1: 24 unreachable 25 26 body: 27 %tmp14 = trunc i64 %tmp8 to i32 28 %tmp15 = trunc i64 %tmp12 to i32 29 %tmp16 = tail call { i32, i1 } @llvm.sadd.with.overflow.i32(i32 %tmp14, i32 %tmp15) 30 %tmp17 = extractvalue { i32, i1 } %tmp16, 1 31 br i1 %tmp17, label %exit2, label %return 32 33 exit2: 34 unreachable 35 36 return: 37 %tmp18 = add i64 %tmp12, %tmp8 38 %tmp19 = and i64 %tmp18, 4294967295 39 %tmp20 = or i64 %tmp19, -281474976710656 40 ret i64 %tmp20 41 } 42 43 declare { i32, i1 } @llvm.sadd.with.overflow.i32(i32, i32) 44
