| ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py |
| ; RUN: llc -verify-machineinstrs -o - %s | FileCheck %s |
| target triple = "arm64--" |
| |
| ; AArch64InstrInfo::optimizeCondBranch() optimizes the |
| ; "x = and y, 256; cmp x, 0; br" from an "and; cbnz" to a tbnz instruction. |
| ; It forgot to clear the a flag resulting in a MachineVerifier complaint. |
| ; |
| ; Writing a stable/simple test is tricky since most tbz instructions are already |
| ; formed in SelectionDAG, optimizeCondBranch() only triggers if the and |
| ; instruction is in a different block than the conditional jump. |
| |
| define void @func() uwtable { |
| ; CHECK-LABEL: func: |
| ; CHECK: // %bb.0: |
| ; CHECK-NEXT: mov w8, #1 // =0x1 |
| ; CHECK-NEXT: cbnz w8, .LBB0_3 |
| ; CHECK-NEXT: // %bb.1: // %b1 |
| ; CHECK-NEXT: cbz wzr, .LBB0_4 |
| ; CHECK-NEXT: // %bb.2: // %b3 |
| ; CHECK-NEXT: ldr w8, [x8] |
| ; CHECK-NEXT: and w0, w8, #0x100 |
| ; CHECK-NEXT: cbz w0, .LBB0_5 |
| ; CHECK-NEXT: .LBB0_3: // %common.ret.sink.split |
| ; CHECK-NEXT: b extfunc |
| ; CHECK-NEXT: .LBB0_4: // %b2 |
| ; CHECK-NEXT: str x30, [sp, #-16]! // 8-byte Folded Spill |
| ; CHECK-NEXT: .cfi_def_cfa_offset 16 |
| ; CHECK-NEXT: .cfi_offset w30, -16 |
| ; CHECK-NEXT: bl extfunc |
| ; CHECK-NEXT: ldr x30, [sp], #16 // 8-byte Folded Reload |
| ; CHECK-NEXT: .cfi_def_cfa_offset 0 |
| ; CHECK-NEXT: .cfi_restore w30 |
| ; CHECK-NEXT: cbnz w0, .LBB0_3 |
| ; CHECK-NEXT: .LBB0_5: // %common.ret |
| ; CHECK-NEXT: ret |
| %c0 = icmp sgt i64 0, 0 |
| br i1 %c0, label %b1, label %b6 |
| |
| b1: |
| br i1 undef, label %b3, label %b2 |
| |
| b2: |
| %v0 = tail call i32 @extfunc() |
| br label %b5 |
| |
| b3: |
| %v1 = load i32, ptr undef, align 4 |
| %v2 = and i32 %v1, 256 |
| br label %b5 |
| |
| b5: |
| %v3 = phi i32 [ %v2, %b3 ], [ %v0, %b2 ] |
| %c1 = icmp eq i32 %v3, 0 |
| br i1 %c1, label %b8, label %b7 |
| |
| b6: |
| tail call i32 @extfunc() |
| ret void |
| |
| b7: |
| tail call i32 @extfunc() |
| ret void |
| |
| b8: |
| ret void |
| } |
| |
| declare i32 @extfunc() |