llvm/test/Transforms/LoopInterchange/indirectbr.ll

; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 6
; RUN: opt < %s -passes=loop-interchange -loop-interchange-profitabilities=ignore -S | FileCheck %s


; The outer loop preheader contains an indirectbr instruction, so we cannot
; interchange the loops.
;
define void @outer_ph_indirectbr(ptr %A) {
; CHECK-LABEL: define void @outer_ph_indirectbr(
; CHECK-SAME: ptr [[A:%.*]]) {
; CHECK-NEXT:  [[ENTRY:.*]]:
; CHECK-NEXT:    indirectbr ptr blockaddress(@outer_ph_indirectbr, %[[OUTER_HEADER:.*]]), [label %[[OUTER_HEADER]]]
; CHECK:       [[OUTER_HEADER]]:
; CHECK-NEXT:    [[I:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[I_INC:%.*]], %[[OUTER_LATCH:.*]] ]
; CHECK-NEXT:    br label %[[INNER:.*]]
; CHECK:       [[INNER]]:
; CHECK-NEXT:    [[J:%.*]] = phi i64 [ 0, %[[OUTER_HEADER]] ], [ [[J_INC:%.*]], %[[INNER]] ]
; CHECK-NEXT:    [[GEP:%.*]] = getelementptr inbounds [4 x i8], ptr [[A]], i64 [[J]], i64 [[I]]
; CHECK-NEXT:    store i8 0, ptr [[GEP]], align 1
; CHECK-NEXT:    [[J_INC]] = add i64 [[J]], 1
; CHECK-NEXT:    [[EC_J:%.*]] = icmp eq i64 [[J_INC]], 4
; CHECK-NEXT:    br i1 [[EC_J]], label %[[OUTER_LATCH]], label %[[INNER]]
; CHECK:       [[OUTER_LATCH]]:
; CHECK-NEXT:    [[I_INC]] = add i64 [[I]], 1
; CHECK-NEXT:    [[EC_I:%.*]] = icmp eq i64 [[I_INC]], 4
; CHECK-NEXT:    br i1 [[EC_I]], label %[[EXIT:.*]], label %[[OUTER_HEADER]]
; CHECK:       [[EXIT]]:
; CHECK-NEXT:    ret void
;
entry:
  indirectbr ptr blockaddress(@outer_ph_indirectbr, %outer.header), [ label %outer.header ]

outer.header:
  %i = phi i64 [ 0, %entry ], [ %i.inc, %outer.latch ]
  br label %inner

inner:
  %j = phi i64 [ 0, %outer.header ], [ %j.inc, %inner ]
  %gep = getelementptr inbounds [4 x i8], ptr %A, i64 %j, i64 %i
  store i8 0, ptr %gep
  %j.inc = add i64 %j, 1
  %ec.j = icmp eq i64 %j.inc, 4
  br i1 %ec.j, label %outer.latch, label %inner

outer.latch:
  %i.inc = add i64 %i, 1
  %ec.i = icmp eq i64 %i.inc, 4
  br i1 %ec.i, label %exit, label %outer.header

exit:
  ret void
}

; The inner loop preheader contains an indirectbr instruction, so we cannot
; interchange the loops.
;
define void @inner_ph_indirectbr(ptr %A) {
; CHECK-LABEL: define void @inner_ph_indirectbr(
; CHECK-SAME: ptr [[A:%.*]]) {
; CHECK-NEXT:  [[ENTRY:.*]]:
; CHECK-NEXT:    br label %[[OUTER_HEADER:.*]]
; CHECK:       [[OUTER_HEADER]]:
; CHECK-NEXT:    [[I:%.*]] = phi i64 [ 0, %[[ENTRY]] ], [ [[I_INC:%.*]], %[[OUTER_LATCH:.*]] ]
; CHECK-NEXT:    indirectbr ptr blockaddress(@inner_ph_indirectbr, %[[INNER:.*]]), [label %[[INNER]]]
; CHECK:       [[INNER]]:
; CHECK-NEXT:    [[J:%.*]] = phi i64 [ 0, %[[OUTER_HEADER]] ], [ [[J_INC:%.*]], %[[INNER]] ]
; CHECK-NEXT:    [[GEP:%.*]] = getelementptr inbounds [4 x i8], ptr [[A]], i64 [[J]], i64 [[I]]
; CHECK-NEXT:    store i8 0, ptr [[GEP]], align 1
; CHECK-NEXT:    [[J_INC]] = add i64 [[J]], 1
; CHECK-NEXT:    [[EC_J:%.*]] = icmp eq i64 [[J_INC]], 4
; CHECK-NEXT:    br i1 [[EC_J]], label %[[OUTER_LATCH]], label %[[INNER]]
; CHECK:       [[OUTER_LATCH]]:
; CHECK-NEXT:    [[I_INC]] = add i64 [[I]], 1
; CHECK-NEXT:    [[EC_I:%.*]] = icmp eq i64 [[I_INC]], 4
; CHECK-NEXT:    br i1 [[EC_I]], label %[[EXIT:.*]], label %[[OUTER_HEADER]]
; CHECK:       [[EXIT]]:
; CHECK-NEXT:    ret void
;
entry:
  br label %outer.header

outer.header:
  %i = phi i64 [ 0, %entry ], [ %i.inc, %outer.latch ]
  indirectbr ptr blockaddress(@inner_ph_indirectbr, %inner), [ label %inner ]

inner:
  %j = phi i64 [ 0, %outer.header ], [ %j.inc, %inner ]
  %gep = getelementptr inbounds [4 x i8], ptr %A, i64 %j, i64 %i
  store i8 0, ptr %gep
  %j.inc = add i64 %j, 1
  %ec.j = icmp eq i64 %j.inc, 4
  br i1 %ec.j, label %outer.latch, label %inner

outer.latch:
  %i.inc = add i64 %i, 1
  %ec.i = icmp eq i64 %i.inc, 4
  br i1 %ec.i, label %exit, label %outer.header

exit:
  ret void
}

; We only support outer loop header PHIs if they are induction variables or if
; they have exactly two incoming values. In common cases, we can reduce the
; number of incoming values to two by inserting a preheader block, but in this
; case we cannot do that because one of the predecessors branches to the outer
; loop header via an indirectbr instruction. Previously, this test case caused
; an assertion failure.
;
define void @indirectbr_to_outer_header(i1 %c, i32 %x, i32 %y, ptr %A) {
; CHECK-LABEL: define void @indirectbr_to_outer_header(
; CHECK-SAME: i1 [[C:%.*]], i32 [[X:%.*]], i32 [[Y:%.*]], ptr [[A:%.*]]) {
; CHECK-NEXT:  [[ENTRY:.*:]]
; CHECK-NEXT:    br i1 [[C]], label %[[ENTRY_0:.*]], label %[[ENTRY_1:.*]]
; CHECK:       [[ENTRY_0]]:
; CHECK-NEXT:    br label %[[OUTER_HEADER:.*]]
; CHECK:       [[ENTRY_1]]:
; CHECK-NEXT:    indirectbr ptr blockaddress(@indirectbr_to_outer_header, %[[OUTER_HEADER]]), [label %[[OUTER_HEADER]]]
; CHECK:       [[OUTER_HEADER]]:
; CHECK-NEXT:    [[I:%.*]] = phi i64 [ 0, %[[ENTRY_0]] ], [ 0, %[[ENTRY_1]] ], [ [[I_NEXT:%.*]], %[[OUTER_LATCH:.*]] ]
; CHECK-NEXT:    [[SEL:%.*]] = phi i32 [ [[X]], %[[ENTRY_0]] ], [ [[Y]], %[[ENTRY_1]] ], [ [[SEL]], %[[OUTER_LATCH]] ]
; CHECK-NEXT:    br label %[[INNER:.*]]
; CHECK:       [[INNER]]:
; CHECK-NEXT:    [[J:%.*]] = phi i64 [ 0, %[[OUTER_HEADER]] ], [ [[J_NEXT:%.*]], %[[INNER]] ]
; CHECK-NEXT:    [[GEP:%.*]] = getelementptr inbounds [256 x i32], ptr [[A]], i64 [[J]], i64 [[I]]
; CHECK-NEXT:    store i32 [[SEL]], ptr [[GEP]], align 4
; CHECK-NEXT:    [[J_NEXT]] = add i64 [[J]], 1
; CHECK-NEXT:    [[EC_J:%.*]] = icmp eq i64 [[J_NEXT]], 256
; CHECK-NEXT:    br i1 [[EC_J]], label %[[OUTER_LATCH]], label %[[INNER]]
; CHECK:       [[OUTER_LATCH]]:
; CHECK-NEXT:    [[I_NEXT]] = add i64 [[I]], 1
; CHECK-NEXT:    [[EC_I:%.*]] = icmp eq i64 [[I_NEXT]], 256
; CHECK-NEXT:    br i1 [[EC_I]], label %[[EXIT:.*]], label %[[OUTER_HEADER]]
; CHECK:       [[EXIT]]:
; CHECK-NEXT:    ret void
;
entry:
  br i1 %c, label %entry.0, label %entry.1

entry.0:
  br label %outer.header

entry.1:
  indirectbr ptr blockaddress(@indirectbr_to_outer_header, %outer.header), [ label %outer.header ]

outer.header:
  %i = phi i64 [ 0, %entry.0 ], [ 0, %entry.1 ], [ %i.next, %outer.latch ]
  %sel = phi i32 [ %x, %entry.0 ], [ %y, %entry.1 ], [ %sel, %outer.latch ]
  br label %inner

inner:
  %j = phi i64 [ 0, %outer.header ], [ %j.next, %inner ]
  %gep = getelementptr inbounds [256 x i32], ptr %A, i64 %j, i64 %i
  store i32 %sel, ptr %gep
  %j.next = add i64 %j, 1
  %ec.j = icmp eq i64 %j.next, 256
  br i1 %ec.j, label %outer.latch, label %inner

outer.latch:
  %i.next = add i64 %i, 1
  %ec.i = icmp eq i64 %i.next, 256
  br i1 %ec.i, label %exit, label %outer.header

exit:
  ret void
}