llvm/test/Transforms/SimpleLoopUnswitch/token-uses.ll

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

declare token @llvm.source_token()
declare void @llvm.sink_token(token)
declare void @a()
declare void @b()

; A token that is used in a different block than its definition, but where all
; uses are still inside the loop, does not prevent non-trivial unswitching:
; cloning the loop only requires forming phis for values that are live-out.
define void @token_used_across_blocks(i32 %n, i1 %cond) {
; CHECK-LABEL: define void @token_used_across_blocks(
; CHECK-SAME: i32 [[N:%.*]], i1 [[COND:%.*]]) {
; CHECK-NEXT:  [[ENTRY:.*:]]
; CHECK-NEXT:    [[COND_FR:%.*]] = freeze i1 [[COND]]
; CHECK-NEXT:    br i1 [[COND_FR]], label %[[ENTRY_SPLIT_US:.*]], label %[[ENTRY_SPLIT:.*]]
; CHECK:       [[ENTRY_SPLIT_US]]:
; CHECK-NEXT:    br label %[[LOOP_US:.*]]
; CHECK:       [[LOOP_US]]:
; CHECK-NEXT:    [[I_US:%.*]] = phi i32 [ 0, %[[ENTRY_SPLIT_US]] ], [ [[I_NEXT_US:%.*]], %[[LATCH_US:.*]] ]
; CHECK-NEXT:    [[TOKEN_US:%.*]] = call token @llvm.source_token()
; CHECK-NEXT:    br label %[[LEFT_US:.*]]
; CHECK:       [[LEFT_US]]:
; CHECK-NEXT:    call void @a()
; CHECK-NEXT:    br label %[[LATCH_US]]
; CHECK:       [[LATCH_US]]:
; CHECK-NEXT:    call void @llvm.sink_token(token [[TOKEN_US]])
; CHECK-NEXT:    [[I_NEXT_US]] = add i32 [[I_US]], 1
; CHECK-NEXT:    [[EXIT_COND_US:%.*]] = icmp slt i32 [[I_NEXT_US]], [[N]]
; CHECK-NEXT:    br i1 [[EXIT_COND_US]], label %[[LOOP_US]], label %[[EXIT_SPLIT_US:.*]]
; CHECK:       [[EXIT_SPLIT_US]]:
; CHECK-NEXT:    br label %[[EXIT:.*]]
; CHECK:       [[ENTRY_SPLIT]]:
; CHECK-NEXT:    br label %[[LOOP:.*]]
; CHECK:       [[LOOP]]:
; CHECK-NEXT:    [[I:%.*]] = phi i32 [ 0, %[[ENTRY_SPLIT]] ], [ [[I_NEXT:%.*]], %[[LATCH:.*]] ]
; CHECK-NEXT:    [[TOKEN:%.*]] = call token @llvm.source_token()
; CHECK-NEXT:    br label %[[RIGHT:.*]]
; CHECK:       [[RIGHT]]:
; CHECK-NEXT:    call void @b()
; CHECK-NEXT:    br label %[[LATCH]]
; CHECK:       [[LATCH]]:
; CHECK-NEXT:    call void @llvm.sink_token(token [[TOKEN]])
; CHECK-NEXT:    [[I_NEXT]] = add i32 [[I]], 1
; CHECK-NEXT:    [[EXIT_COND:%.*]] = icmp slt i32 [[I_NEXT]], [[N]]
; CHECK-NEXT:    br i1 [[EXIT_COND]], label %[[LOOP]], label %[[EXIT_SPLIT:.*]]
; CHECK:       [[EXIT_SPLIT]]:
; CHECK-NEXT:    br label %[[EXIT]]
; CHECK:       [[EXIT]]:
; CHECK-NEXT:    ret void
;
entry:
  br label %loop

loop:
  %i = phi i32 [ 0, %entry ], [ %i.next, %latch ]
  %token = call token @llvm.source_token()
  br i1 %cond, label %left, label %right

left:
  call void @a()
  br label %latch

right:
  call void @b()
  br label %latch

latch:
  call void @llvm.sink_token(token %token)
  %i.next = add i32 %i, 1
  %exit.cond = icmp slt i32 %i.next, %n
  br i1 %exit.cond, label %loop, label %exit

exit:
  ret void
}

; A token that is live-out of the loop still prevents unswitching: we cannot
; form a phi for it in the exit block.
define void @token_live_out(i32 %n, i1 %cond) {
; CHECK-LABEL: define void @token_live_out(
; CHECK-SAME: i32 [[N:%.*]], i1 [[COND:%.*]]) {
; CHECK-NEXT:  [[ENTRY:.*]]:
; CHECK-NEXT:    br label %[[LOOP:.*]]
; CHECK:       [[LOOP]]:
; CHECK-NEXT:    [[I:%.*]] = phi i32 [ 0, %[[ENTRY]] ], [ [[I_NEXT:%.*]], %[[LATCH:.*]] ]
; CHECK-NEXT:    [[TOKEN:%.*]] = call token @llvm.source_token()
; CHECK-NEXT:    br i1 [[COND]], label %[[LEFT:.*]], label %[[RIGHT:.*]]
; CHECK:       [[LEFT]]:
; CHECK-NEXT:    call void @a()
; CHECK-NEXT:    br label %[[LATCH]]
; CHECK:       [[RIGHT]]:
; CHECK-NEXT:    call void @b()
; CHECK-NEXT:    br label %[[LATCH]]
; CHECK:       [[LATCH]]:
; CHECK-NEXT:    [[I_NEXT]] = add i32 [[I]], 1
; CHECK-NEXT:    [[EXIT_COND:%.*]] = icmp slt i32 [[I_NEXT]], [[N]]
; CHECK-NEXT:    br i1 [[EXIT_COND]], label %[[LOOP]], label %[[EXIT:.*]]
; CHECK:       [[EXIT]]:
; CHECK-NEXT:    call void @llvm.sink_token(token [[TOKEN]])
; CHECK-NEXT:    ret void
;
entry:
  br label %loop

loop:
  %i = phi i32 [ 0, %entry ], [ %i.next, %latch ]
  %token = call token @llvm.source_token()
  br i1 %cond, label %left, label %right

left:
  call void @a()
  br label %latch

right:
  call void @b()
  br label %latch

latch:
  %i.next = add i32 %i, 1
  %exit.cond = icmp slt i32 %i.next, %n
  br i1 %exit.cond, label %loop, label %exit

exit:
  call void @llvm.sink_token(token %token)
  ret void
}

; Same for live-out token-like target extension types, which cannot be used in
; phi nodes either.
define void @token_like_live_out(i32 %n, i1 %cond) {
; CHECK-LABEL: define void @token_like_live_out(
; CHECK-SAME: i32 [[N:%.*]], i1 [[COND:%.*]]) {
; CHECK-NEXT:  [[ENTRY:.*]]:
; CHECK-NEXT:    br label %[[LOOP:.*]]
; CHECK:       [[LOOP]]:
; CHECK-NEXT:    [[I:%.*]] = phi i32 [ 0, %[[ENTRY]] ], [ [[I_NEXT:%.*]], %[[LATCH:.*]] ]
; CHECK-NEXT:    [[TOKEN:%.*]] = call target("amdgpu.stridemark") @llvm.ssa.copy.tamdgpu.stridemarkt(target("amdgpu.stridemark") poison)
; CHECK-NEXT:    br i1 [[COND]], label %[[LEFT:.*]], label %[[RIGHT:.*]]
; CHECK:       [[LEFT]]:
; CHECK-NEXT:    call void @a()
; CHECK-NEXT:    br label %[[LATCH]]
; CHECK:       [[RIGHT]]:
; CHECK-NEXT:    call void @b()
; CHECK-NEXT:    br label %[[LATCH]]
; CHECK:       [[LATCH]]:
; CHECK-NEXT:    [[I_NEXT]] = add i32 [[I]], 1
; CHECK-NEXT:    [[EXIT_COND:%.*]] = icmp slt i32 [[I_NEXT]], [[N]]
; CHECK-NEXT:    br i1 [[EXIT_COND]], label %[[LOOP]], label %[[EXIT:.*]]
; CHECK:       [[EXIT]]:
; CHECK-NEXT:    call target("amdgpu.stridemark") @llvm.ssa.copy.tamdgpu.stridemarkt(target("amdgpu.stridemark") [[TOKEN]])
; CHECK-NEXT:    ret void
;
entry:
  br label %loop

loop:
  %i = phi i32 [ 0, %entry ], [ %i.next, %latch ]
  %token = call target("amdgpu.stridemark") @llvm.ssa.copy(target("amdgpu.stridemark") poison)
  br i1 %cond, label %left, label %right

left:
  call void @a()
  br label %latch

right:
  call void @b()
  br label %latch

latch:
  %i.next = add i32 %i, 1
  %exit.cond = icmp slt i32 %i.next, %n
  br i1 %exit.cond, label %loop, label %exit

exit:
  %use = call target("amdgpu.stridemark") @llvm.ssa.copy(target("amdgpu.stridemark") %token)
  ret void
}