| Craig Topper | 18a9d54 | 2018-12-18 20:03:54 +0000 | [diff] [blame] | 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 | |
| 4 | define i64 @foo(i64 %x, i64 %y) { |
| 5 | ; CHECK-LABEL: foo: |
| 6 | ; CHECK: # %bb.0: |
| 7 | ; CHECK-NEXT: bsrq %rdi, %rax |
| 8 | ; CHECK-NEXT: xorq $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 | |
| 24 | declare i64 @llvm.ctlz.i64(i64, i1) |