implicit-null-checks.ll
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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -enable-nontrivial-unswitch=true -simple-loop-unswitch -S < %s | FileCheck %s
; RUN: opt -enable-nontrivial-unswitch=true -passes='loop(unswitch),verify<loops>' -S < %s | FileCheck %s
declare void @may_exit()
declare void @throw_npe()
; It is illegal to preserve make_implicit notion of the condition being
; unswitched because we may exit loop before we reach the condition, so
; there is no guarantee that following implicit branch always means getting
; to throw_npe block.
define i32 @test_should_drop_make_implicit(i32* %p1, i32* %p2) {
; CHECK-LABEL: @test_should_drop_make_implicit(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[NULL_CHECK:%.*]] = icmp eq i32* [[P2:%.*]], null
; CHECK-NOT: !make.implicit
; CHECK-NEXT: br i1 [[NULL_CHECK]], label [[ENTRY_SPLIT_US:%.*]], label [[ENTRY_SPLIT:%.*]]
; CHECK: entry.split.us:
; CHECK-NEXT: br label [[LOOP_US:%.*]]
; CHECK: loop.us:
; CHECK-NEXT: [[IV_US:%.*]] = phi i32 [ 0, [[ENTRY_SPLIT_US]] ]
; CHECK-NEXT: [[X_US:%.*]] = load i32, i32* [[P1:%.*]], align 4
; CHECK-NEXT: [[SIDE_EXIT_COND_US:%.*]] = icmp eq i32 [[X_US]], 0
; CHECK-NEXT: br i1 [[SIDE_EXIT_COND_US]], label [[SIDE_EXIT_SPLIT_US:%.*]], label [[NULL_CHECK_BLOCK_US:%.*]]
; CHECK: null_check_block.us:
; CHECK-NEXT: br label [[THROW_NPE_SPLIT_US:%.*]]
; CHECK: side_exit.split.us:
; CHECK-NEXT: br label [[SIDE_EXIT:%.*]]
; CHECK: throw_npe.split.us:
; CHECK-NEXT: br label [[THROW_NPE:%.*]]
; CHECK: entry.split:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY_SPLIT]] ], [ [[IV_NEXT:%.*]], [[BACKEDGE:%.*]] ]
; CHECK-NEXT: [[X:%.*]] = load i32, i32* [[P1]], align 4
; CHECK-NEXT: [[SIDE_EXIT_COND:%.*]] = icmp eq i32 [[X]], 0
; CHECK-NEXT: br i1 [[SIDE_EXIT_COND]], label [[SIDE_EXIT_SPLIT:%.*]], label [[NULL_CHECK_BLOCK:%.*]]
; CHECK: null_check_block:
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: backedge:
; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1
; CHECK-NEXT: [[LOOP_COND:%.*]] = icmp slt i32 [[IV_NEXT]], 10000
; CHECK-NEXT: br i1 [[LOOP_COND]], label [[LOOP]], label [[EXIT:%.*]]
; CHECK: side_exit.split:
; CHECK-NEXT: br label [[SIDE_EXIT]]
; CHECK: side_exit:
; CHECK-NEXT: ret i32 0
; CHECK: throw_npe:
; CHECK-NEXT: call void @throw_npe()
; CHECK-NEXT: unreachable
; CHECK: exit:
; CHECK-NEXT: [[X_LCSSA2:%.*]] = phi i32 [ [[X]], [[BACKEDGE]] ]
; CHECK-NEXT: ret i32 [[X_LCSSA2]]
;
entry:
%null_check = icmp eq i32* %p2, null
br label %loop
loop:
%iv = phi i32 [0, %entry], [%iv.next, %backedge]
%x = load i32, i32* %p1
%side_exit_cond = icmp eq i32 %x, 0
br i1 %side_exit_cond, label %side_exit, label %null_check_block
null_check_block:
br i1 %null_check, label %throw_npe, label %backedge, !make.implicit !0
backedge:
%iv.next = add i32 %iv,1
%loop_cond = icmp slt i32 %iv.next, 10000
br i1 %loop_cond, label %loop, label %exit
side_exit:
ret i32 0
throw_npe:
call void @throw_npe()
unreachable
exit:
ret i32 %x
}
; Here make.implicit notion may be preserved because we always get to throw_npe
; after following true branch. This is a trivial unswitch.
define i32 @test_may_keep_make_implicit_trivial(i32* %p1, i32* %p2) {
; CHECK-LABEL: @test_may_keep_make_implicit_trivial(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[NULL_CHECK:%.*]] = icmp eq i32* [[P2:%.*]], null
; CHECK-NEXT: br i1 [[NULL_CHECK]], label [[THROW_NPE:%.*]], label [[ENTRY_SPLIT:%.*]], !make.implicit !0
; CHECK: entry.split:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY_SPLIT]] ], [ [[IV_NEXT:%.*]], [[BACKEDGE:%.*]] ]
; CHECK-NEXT: [[X:%.*]] = load i32, i32* [[P1:%.*]], align 4
; CHECK-NEXT: [[SIDE_EXIT_COND:%.*]] = icmp eq i32 [[X]], 0
; CHECK-NEXT: br label [[SIDE_EXIT_BLOCK:%.*]]
; CHECK: side_exit_block:
; CHECK-NEXT: br i1 [[SIDE_EXIT_COND]], label [[SIDE_EXIT:%.*]], label [[BACKEDGE]]
; CHECK: backedge:
; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1
; CHECK-NEXT: [[LOOP_COND:%.*]] = icmp slt i32 [[IV_NEXT]], 10000
; CHECK-NEXT: br i1 [[LOOP_COND]], label [[LOOP]], label [[EXIT:%.*]]
; CHECK: side_exit:
; CHECK-NEXT: ret i32 0
; CHECK: throw_npe:
; CHECK-NEXT: call void @throw_npe()
; CHECK-NEXT: unreachable
; CHECK: exit:
; CHECK-NEXT: [[X_LCSSA2:%.*]] = phi i32 [ [[X]], [[BACKEDGE]] ]
; CHECK-NEXT: ret i32 [[X_LCSSA2]]
;
entry:
%null_check = icmp eq i32* %p2, null
br label %loop
loop:
%iv = phi i32 [0, %entry], [%iv.next, %backedge]
%x = load i32, i32* %p1
%side_exit_cond = icmp eq i32 %x, 0
br i1 %null_check, label %throw_npe, label %side_exit_block, !make.implicit !0
side_exit_block:
br i1 %side_exit_cond, label %side_exit, label %backedge
backedge:
%iv.next = add i32 %iv,1
%loop_cond = icmp slt i32 %iv.next, 10000
br i1 %loop_cond, label %loop, label %exit
side_exit:
ret i32 0
throw_npe:
call void @throw_npe()
unreachable
exit:
ret i32 %x
}
define i32 @test_may_keep_make_implicit_non_trivial(i32* %p1, i32* %p2) {
; CHECK-LABEL: @test_may_keep_make_implicit_non_trivial(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[NULL_CHECK:%.*]] = icmp eq i32* [[P2:%.*]], null
; CHECK-NEXT: br i1 [[NULL_CHECK]], label [[ENTRY_SPLIT_US:%.*]], label [[ENTRY_SPLIT:%.*]], !make.implicit !0
; CHECK: entry.split.us:
; CHECK-NEXT: br label [[LOOP_US:%.*]]
; CHECK: loop.us:
; CHECK-NEXT: [[IV_US:%.*]] = phi i32 [ 0, [[ENTRY_SPLIT_US]] ]
; CHECK-NEXT: [[X_US:%.*]] = load i32, i32* [[P1:%.*]], align 4
; CHECK-NEXT: [[INNER_BLOCK_COND_US:%.*]] = icmp eq i32 [[X_US]], 0
; CHECK-NEXT: br i1 [[INNER_BLOCK_COND_US]], label [[INNER_BLOCK_US:%.*]], label [[NULL_CHECK_BLOCK_US:%.*]]
; CHECK: inner_block.us:
; CHECK-NEXT: br label [[NULL_CHECK_BLOCK_US]]
; CHECK: null_check_block.us:
; CHECK-NEXT: br label [[THROW_NPE_SPLIT_US:%.*]]
; CHECK: throw_npe.split.us:
; CHECK-NEXT: br label [[THROW_NPE:%.*]]
; CHECK: entry.split:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY_SPLIT]] ], [ [[IV_NEXT:%.*]], [[BACKEDGE:%.*]] ]
; CHECK-NEXT: [[X:%.*]] = load i32, i32* [[P1]], align 4
; CHECK-NEXT: [[INNER_BLOCK_COND:%.*]] = icmp eq i32 [[X]], 0
; CHECK-NEXT: br i1 [[INNER_BLOCK_COND]], label [[INNER_BLOCK:%.*]], label [[NULL_CHECK_BLOCK:%.*]]
; CHECK: inner_block:
; CHECK-NEXT: br label [[NULL_CHECK_BLOCK]]
; CHECK: null_check_block:
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: backedge:
; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1
; CHECK-NEXT: [[LOOP_COND:%.*]] = icmp slt i32 [[IV_NEXT]], 10000
; CHECK-NEXT: br i1 [[LOOP_COND]], label [[LOOP]], label [[EXIT:%.*]]
; CHECK: throw_npe:
; CHECK-NEXT: call void @throw_npe()
; CHECK-NEXT: unreachable
; CHECK: exit:
; CHECK-NEXT: [[X_LCSSA1:%.*]] = phi i32 [ [[X]], [[BACKEDGE]] ]
; CHECK-NEXT: ret i32 [[X_LCSSA1]]
;
entry:
%null_check = icmp eq i32* %p2, null
br label %loop
loop:
%iv = phi i32 [0, %entry], [%iv.next, %backedge]
%x = load i32, i32* %p1
%inner_block_cond = icmp eq i32 %x, 0
br i1 %inner_block_cond, label %inner_block, label %null_check_block
inner_block:
br label %null_check_block
null_check_block:
br i1 %null_check, label %throw_npe, label %backedge, !make.implicit !0
backedge:
%iv.next = add i32 %iv,1
%loop_cond = icmp slt i32 %iv.next, 10000
br i1 %loop_cond, label %loop, label %exit
throw_npe:
call void @throw_npe()
unreachable
exit:
ret i32 %x
}
; Here make.implicit notion should be dropped because of exiting call.
define i32 @test_should_drop_make_implicit_exiting_call(i32* %p1, i32* %p2) {
; CHECK-LABEL: @test_should_drop_make_implicit_exiting_call(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[NULL_CHECK:%.*]] = icmp eq i32* [[P2:%.*]], null
; CHECK-NOT: !make.implicit
; CHECK-NEXT: br i1 [[NULL_CHECK]], label [[ENTRY_SPLIT_US:%.*]], label [[ENTRY_SPLIT:%.*]]
; CHECK: entry.split.us:
; CHECK-NEXT: br label [[LOOP_US:%.*]]
; CHECK: loop.us:
; CHECK-NEXT: [[IV_US:%.*]] = phi i32 [ 0, [[ENTRY_SPLIT_US]] ]
; CHECK-NEXT: call void @may_exit()
; CHECK-NEXT: [[X_US:%.*]] = load i32, i32* [[P1:%.*]], align 4
; CHECK-NEXT: [[SIDE_EXIT_COND_US:%.*]] = icmp eq i32 [[X_US]], 0
; CHECK-NEXT: br label [[THROW_NPE_SPLIT_US:%.*]]
; CHECK: throw_npe.split.us:
; CHECK-NEXT: br label [[THROW_NPE:%.*]]
; CHECK: entry.split:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY_SPLIT]] ], [ [[IV_NEXT:%.*]], [[BACKEDGE:%.*]] ]
; CHECK-NEXT: call void @may_exit()
; CHECK-NEXT: [[X:%.*]] = load i32, i32* [[P1]], align 4
; CHECK-NEXT: [[SIDE_EXIT_COND:%.*]] = icmp eq i32 [[X]], 0
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: backedge:
; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1
; CHECK-NEXT: [[LOOP_COND:%.*]] = icmp slt i32 [[IV_NEXT]], 10000
; CHECK-NEXT: br i1 [[LOOP_COND]], label [[LOOP]], label [[EXIT:%.*]]
; CHECK: throw_npe:
; CHECK-NEXT: call void @throw_npe()
; CHECK-NEXT: unreachable
; CHECK: exit:
; CHECK-NEXT: [[X_LCSSA1:%.*]] = phi i32 [ [[X]], [[BACKEDGE]] ]
; CHECK-NEXT: ret i32 [[X_LCSSA1]]
;
entry:
%null_check = icmp eq i32* %p2, null
br label %loop
loop:
%iv = phi i32 [0, %entry], [%iv.next, %backedge]
call void @may_exit()
%x = load i32, i32* %p1
%side_exit_cond = icmp eq i32 %x, 0
br i1 %null_check, label %throw_npe, label %backedge, !make.implicit !0
backedge:
%iv.next = add i32 %iv,1
%loop_cond = icmp slt i32 %iv.next, 10000
br i1 %loop_cond, label %loop, label %exit
throw_npe:
call void @throw_npe()
unreachable
exit:
ret i32 %x
}
; Here exiting call goes after the null check, so make.implicit may be preserved.
define i32 @test_may_keep_make_implicit_exiting_call(i32* %p1, i32* %p2) {
; CHECK-LABEL: @test_may_keep_make_implicit_exiting_call(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[NULL_CHECK:%.*]] = icmp eq i32* [[P2:%.*]], null
; CHECK-NEXT: br i1 [[NULL_CHECK]], label [[THROW_NPE:%.*]], label [[ENTRY_SPLIT:%.*]], !make.implicit !0
; CHECK: entry.split:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY_SPLIT]] ], [ [[IV_NEXT:%.*]], [[BACKEDGE:%.*]] ]
; CHECK-NEXT: [[X:%.*]] = load i32, i32* [[P1:%.*]], align 4
; CHECK-NEXT: [[SIDE_EXIT_COND:%.*]] = icmp eq i32 [[X]], 0
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: backedge:
; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1
; CHECK-NEXT: [[LOOP_COND:%.*]] = icmp slt i32 [[IV_NEXT]], 10000
; CHECK-NEXT: call void @may_exit()
; CHECK-NEXT: br i1 [[LOOP_COND]], label [[LOOP]], label [[EXIT:%.*]]
; CHECK: throw_npe:
; CHECK-NEXT: call void @throw_npe()
; CHECK-NEXT: unreachable
; CHECK: exit:
; CHECK-NEXT: [[X_LCSSA1:%.*]] = phi i32 [ [[X]], [[BACKEDGE]] ]
; CHECK-NEXT: ret i32 [[X_LCSSA1]]
;
entry:
%null_check = icmp eq i32* %p2, null
br label %loop
loop:
%iv = phi i32 [0, %entry], [%iv.next, %backedge]
%x = load i32, i32* %p1
%side_exit_cond = icmp eq i32 %x, 0
br i1 %null_check, label %throw_npe, label %backedge, !make.implicit !0
backedge:
%iv.next = add i32 %iv,1
%loop_cond = icmp slt i32 %iv.next, 10000
call void @may_exit()
br i1 %loop_cond, label %loop, label %exit
throw_npe:
call void @throw_npe()
unreachable
exit:
ret i32 %x
}
!0 = !{}