; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 6
; RUN: opt -aa-pipeline=basic-aa -passes='require<aa>,require<target-ir>,require<scalar-evolution>,require<opt-remark-emit>,loop-mssa(licm)' < %s -S | FileCheck %s

; We should be able to hoist loads in presence of read only calls and stores
; that do not alias.

; Since LICM uses the AST mechanism for alias analysis, we will clump
; together all loads and stores in one set along with the read-only call.
; This prevents hoisting load that doesn't alias with any other memory
; operations.

declare void @foo(i64, ptr) readonly

; hoist the load out with the n2-threshold
; since it doesn't alias with the store.
; default AST mechanism clumps all memory locations in one set because of the
; readonly call
define void @test1(ptr %ptr) {
; CHECK-LABEL: define void @test1(
; CHECK-SAME: ptr [[PTR:%.*]]) {
; CHECK-NEXT:  [[ENTRY:.*]]:
; CHECK-NEXT:    [[VAL:%.*]] = load i32, ptr [[PTR]], align 4
; CHECK-NEXT:    [[P2:%.*]] = getelementptr i32, ptr [[PTR]], i32 1
; CHECK-NEXT:    br label %[[LOOP:.*]]
; CHECK:       [[LOOP]]:
; CHECK-NEXT:    [[X:%.*]] = phi i32 [ 0, %[[ENTRY]] ], [ [[X_INC:%.*]], %[[LOOP]] ]
; CHECK-NEXT:    call void @foo(i64 4, ptr [[PTR]])
; CHECK-NEXT:    store volatile i32 0, ptr [[P2]], align 4
; CHECK-NEXT:    [[X_INC]] = add i32 [[X]], [[VAL]]
; CHECK-NEXT:    br label %[[LOOP]]
;
entry:
  br label %loop

loop:
  %x = phi i32 [ 0, %entry ], [ %x.inc, %loop ]
  %val = load i32, ptr %ptr
  call void @foo(i64 4, ptr %ptr)
  %p2 = getelementptr i32, ptr %ptr, i32 1
  store volatile i32 0, ptr %p2
  %x.inc = add i32 %x, %val
  br label %loop
}

; can hoist out load with the default AST and the alias analysis mechanism.
define void @test2(ptr %ptr) {
; CHECK-LABEL: define void @test2(
; CHECK-SAME: ptr [[PTR:%.*]]) {
; CHECK-NEXT:  [[ENTRY:.*]]:
; CHECK-NEXT:    [[VAL:%.*]] = load i32, ptr [[PTR]], align 4
; CHECK-NEXT:    br label %[[LOOP:.*]]
; CHECK:       [[LOOP]]:
; CHECK-NEXT:    [[X:%.*]] = phi i32 [ 0, %[[ENTRY]] ], [ [[X_INC:%.*]], %[[LOOP]] ]
; CHECK-NEXT:    call void @foo(i64 4, ptr [[PTR]])
; CHECK-NEXT:    [[X_INC]] = add i32 [[X]], [[VAL]]
; CHECK-NEXT:    br label %[[LOOP]]
;
entry:
  br label %loop

loop:
  %x = phi i32 [ 0, %entry ], [ %x.inc, %loop ]
  %val = load i32, ptr %ptr
  call void @foo(i64 4, ptr %ptr)
  %x.inc = add i32 %x, %val
  br label %loop
}

; cannot hoist load since not guaranteed to execute
define void @test3(ptr %ptr) {
; CHECK-LABEL: define void @test3(
; CHECK-SAME: ptr [[PTR:%.*]]) {
; CHECK-NEXT:  [[ENTRY:.*]]:
; CHECK-NEXT:    br label %[[LOOP:.*]]
; CHECK:       [[LOOP]]:
; CHECK-NEXT:    [[X:%.*]] = phi i32 [ 0, %[[ENTRY]] ], [ [[X_INC:%.*]], %[[LOOP]] ]
; CHECK-NEXT:    call void @foo(i64 4, ptr [[PTR]])
; CHECK-NEXT:    [[VAL:%.*]] = load i32, ptr [[PTR]], align 4
; CHECK-NEXT:    [[X_INC]] = add i32 [[X]], [[VAL]]
; CHECK-NEXT:    br label %[[LOOP]]
;
entry:
  br label %loop

loop:
  %x = phi i32 [ 0, %entry ], [ %x.inc, %loop ]
  call void @foo(i64 4, ptr %ptr)
  %val = load i32, ptr %ptr
  %x.inc = add i32 %x, %val
  br label %loop
}