1; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py 2; RUN: llc < %s -mtriple=x86_64-unknown-unknown | FileCheck %s 3 4define i64 @foo(i64 %x, i64 %y) { 5; CHECK-LABEL: foo: 6; CHECK: # %bb.0: 7; CHECK-NEXT: bsrq %rdi, %rax 8; CHECK-NEXT: orq $64, %rax 9; CHECK-NEXT: bsrq %rsi, %rcx 10; CHECK-NEXT: cmoveq %rax, %rcx 11; CHECK-NEXT: movl $63, %eax 12; CHECK-NEXT: subq %rcx, %rax 13; CHECK-NEXT: retq 14 %1 = tail call i64 @llvm.ctlz.i64(i64 %x, i1 true) 15 %2 = xor i64 %1, 127 16 %3 = tail call i64 @llvm.ctlz.i64(i64 %y, i1 true) 17 %4 = xor i64 %3, 63 18 %5 = icmp eq i64 %y, 0 19 %6 = select i1 %5, i64 %2, i64 %4 20 %7 = sub nsw i64 63, %6 21 ret i64 %7 22} 23 24declare i64 @llvm.ctlz.i64(i64, i1) 25