llvm/test/Transforms/SimpleLoopUnswitch/trivial-unswitch-droppable.ll

; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 6
; RUN: opt -passes='loop-mssa(simple-loop-unswitch),verify<loops>' -S < %s | FileCheck %s

; Check that an llvm.assume ahead of an invariant exiting branch does not block
; trivial unswitching.
define void @assume_before_branch(ptr %p, i1 %c, i64 %n) {
; CHECK-LABEL: define void @assume_before_branch(
; CHECK-SAME: ptr [[P:%.*]], i1 [[C:%.*]], i64 [[N:%.*]]) {
; CHECK-NEXT:  [[ENTRY:.*:]]
; CHECK-NEXT:    br i1 [[C]], label %[[EXIT_SPLIT:.*]], label %[[ENTRY_SPLIT:.*]]
; CHECK:       [[ENTRY_SPLIT]]:
; CHECK-NEXT:    br label %[[LOOP:.*]]
; CHECK:       [[LOOP]]:
; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[ENTRY_SPLIT]] ], [ [[IV_NEXT:%.*]], %[[LATCH:.*]] ]
; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i64 [[IV]], [[N]]
; CHECK-NEXT:    call void @llvm.assume(i1 [[CMP]])
; CHECK-NEXT:    br label %[[LATCH]]
; CHECK:       [[LATCH]]:
; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i32, ptr [[P]], i64 [[IV]]
; CHECK-NEXT:    store i32 0, ptr [[GEP]], align 4
; CHECK-NEXT:    [[IV_NEXT]] = add nuw i64 [[IV]], 1
; CHECK-NEXT:    [[DONE:%.*]] = icmp eq i64 [[IV_NEXT]], [[N]]
; CHECK-NEXT:    br i1 [[DONE]], label %[[EXIT:.*]], label %[[LOOP]]
; CHECK:       [[EXIT]]:
; CHECK-NEXT:    br label %[[EXIT_SPLIT]]
; CHECK:       [[EXIT_SPLIT]]:
; CHECK-NEXT:    ret void
;
entry:
  br label %loop

loop:
  %iv = phi i64 [ 0, %entry ], [ %iv.next, %latch ]
  %cmp = icmp ult i64 %iv, %n
  call void @llvm.assume(i1 %cmp)
  br i1 %c, label %exit, label %latch

latch:
  %gep = getelementptr i32, ptr %p, i64 %iv
  store i32 0, ptr %gep
  %iv.next = add nuw i64 %iv, 1
  %done = icmp eq i64 %iv.next, %n
  br i1 %done, label %exit, label %loop

exit:
  ret void
}

; Check that an llvm.assume with operand bundles ahead of an invariant exiting
; branch does not block trivial unswitching.
define void @assume_bundle_before_branch(ptr %p, i1 %c, i64 %n) {
; CHECK-LABEL: define void @assume_bundle_before_branch(
; CHECK-SAME: ptr [[P:%.*]], i1 [[C:%.*]], i64 [[N:%.*]]) {
; CHECK-NEXT:  [[ENTRY:.*:]]
; CHECK-NEXT:    br i1 [[C]], label %[[EXIT_SPLIT:.*]], label %[[ENTRY_SPLIT:.*]]
; CHECK:       [[ENTRY_SPLIT]]:
; CHECK-NEXT:    br label %[[LOOP:.*]]
; CHECK:       [[LOOP]]:
; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[ENTRY_SPLIT]] ], [ [[IV_NEXT:%.*]], %[[LATCH:.*]] ]
; CHECK-NEXT:    call void @llvm.assume(i1 true) [ "align"(ptr [[P]], i64 4) ]
; CHECK-NEXT:    br label %[[LATCH]]
; CHECK:       [[LATCH]]:
; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i32, ptr [[P]], i64 [[IV]]
; CHECK-NEXT:    store i32 0, ptr [[GEP]], align 4
; CHECK-NEXT:    [[IV_NEXT]] = add nuw i64 [[IV]], 1
; CHECK-NEXT:    [[DONE:%.*]] = icmp eq i64 [[IV_NEXT]], [[N]]
; CHECK-NEXT:    br i1 [[DONE]], label %[[EXIT:.*]], label %[[LOOP]]
; CHECK:       [[EXIT]]:
; CHECK-NEXT:    br label %[[EXIT_SPLIT]]
; CHECK:       [[EXIT_SPLIT]]:
; CHECK-NEXT:    ret void
;
entry:
  br label %loop

loop:
  %iv = phi i64 [ 0, %entry ], [ %iv.next, %latch ]
  call void @llvm.assume(i1 true) [ "align"(ptr %p, i64 4) ]
  br i1 %c, label %exit, label %latch

latch:
  %gep = getelementptr i32, ptr %p, i64 %iv
  store i32 0, ptr %gep
  %iv.next = add nuw i64 %iv, 1
  %done = icmp eq i64 %iv.next, %n
  br i1 %done, label %exit, label %loop

exit:
  ret void
}

; Check that an llvm.experimental.noalias.scope.decl ahead of an invariant
; exiting branch does not block trivial unswitching.
define void @noalias_scope_decl_before_branch(ptr %p, i1 %c, i64 %n) {
; CHECK-LABEL: define void @noalias_scope_decl_before_branch(
; CHECK-SAME: ptr [[P:%.*]], i1 [[C:%.*]], i64 [[N:%.*]]) {
; CHECK-NEXT:  [[ENTRY:.*:]]
; CHECK-NEXT:    br i1 [[C]], label %[[EXIT_SPLIT:.*]], label %[[ENTRY_SPLIT:.*]]
; CHECK:       [[ENTRY_SPLIT]]:
; CHECK-NEXT:    br label %[[LOOP:.*]]
; CHECK:       [[LOOP]]:
; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[ENTRY_SPLIT]] ], [ [[IV_NEXT:%.*]], %[[LATCH:.*]] ]
; CHECK-NEXT:    call void @llvm.experimental.noalias.scope.decl(metadata [[META0:![0-9]+]])
; CHECK-NEXT:    br label %[[LATCH]]
; CHECK:       [[LATCH]]:
; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i32, ptr [[P]], i64 [[IV]]
; CHECK-NEXT:    store i32 0, ptr [[GEP]], align 4, !alias.scope [[META0]]
; CHECK-NEXT:    [[IV_NEXT]] = add nuw i64 [[IV]], 1
; CHECK-NEXT:    [[DONE:%.*]] = icmp eq i64 [[IV_NEXT]], [[N]]
; CHECK-NEXT:    br i1 [[DONE]], label %[[EXIT:.*]], label %[[LOOP]]
; CHECK:       [[EXIT]]:
; CHECK-NEXT:    br label %[[EXIT_SPLIT]]
; CHECK:       [[EXIT_SPLIT]]:
; CHECK-NEXT:    ret void
;
entry:
  br label %loop

loop:
  %iv = phi i64 [ 0, %entry ], [ %iv.next, %latch ]
  call void @llvm.experimental.noalias.scope.decl(metadata !0)
  br i1 %c, label %exit, label %latch

latch:
  %gep = getelementptr i32, ptr %p, i64 %iv
  store i32 0, ptr %gep, !alias.scope !0
  %iv.next = add nuw i64 %iv, 1
  %done = icmp eq i64 %iv.next, %n
  br i1 %done, label %exit, label %loop

exit:
  ret void
}

; Check that an llvm.pseudoprobe ahead of an invariant exiting branch does not
; block trivial unswitching.
define void @pseudoprobe_before_branch(ptr %p, i1 %c, i64 %n) {
; CHECK-LABEL: define void @pseudoprobe_before_branch(
; CHECK-SAME: ptr [[P:%.*]], i1 [[C:%.*]], i64 [[N:%.*]]) {
; CHECK-NEXT:  [[ENTRY:.*:]]
; CHECK-NEXT:    br i1 [[C]], label %[[EXIT_SPLIT:.*]], label %[[ENTRY_SPLIT:.*]]
; CHECK:       [[ENTRY_SPLIT]]:
; CHECK-NEXT:    br label %[[LOOP:.*]]
; CHECK:       [[LOOP]]:
; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, %[[ENTRY_SPLIT]] ], [ [[IV_NEXT:%.*]], %[[LATCH:.*]] ]
; CHECK-NEXT:    call void @llvm.pseudoprobe(i64 123, i64 2, i32 0, i64 -1)
; CHECK-NEXT:    br label %[[LATCH]]
; CHECK:       [[LATCH]]:
; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i32, ptr [[P]], i64 [[IV]]
; CHECK-NEXT:    store i32 0, ptr [[GEP]], align 4
; CHECK-NEXT:    [[IV_NEXT]] = add nuw i64 [[IV]], 1
; CHECK-NEXT:    [[DONE:%.*]] = icmp eq i64 [[IV_NEXT]], [[N]]
; CHECK-NEXT:    br i1 [[DONE]], label %[[EXIT:.*]], label %[[LOOP]]
; CHECK:       [[EXIT]]:
; CHECK-NEXT:    br label %[[EXIT_SPLIT]]
; CHECK:       [[EXIT_SPLIT]]:
; CHECK-NEXT:    ret void
;
entry:
  br label %loop

loop:
  %iv = phi i64 [ 0, %entry ], [ %iv.next, %latch ]
  call void @llvm.pseudoprobe(i64 123, i64 2, i32 0, i64 -1)
  br i1 %c, label %exit, label %latch

latch:
  %gep = getelementptr i32, ptr %p, i64 %iv
  store i32 0, ptr %gep
  %iv.next = add nuw i64 %iv, 1
  %done = icmp eq i64 %iv.next, %n
  br i1 %done, label %exit, label %loop

exit:
  ret void
}

declare void @llvm.assume(i1)
declare void @llvm.experimental.noalias.scope.decl(metadata)
declare void @llvm.pseudoprobe(i64, i64, i32, i64)

!0 = !{!1}
!1 = distinct !{!1, !2, !"scope"}
!2 = distinct !{!2, i1 false, !"domain"}
;.
; CHECK: [[META0]] = !{[[META1:![0-9]+]]}
; CHECK: [[META1]] = distinct !{[[META1]], [[META2:![0-9]+]], !"scope"}
; CHECK: [[META2]] = distinct !{[[META2]], i1 false, !"domain"}
;.