/
nontrivial-unswitch.ll
4381 lines (3988 loc) · 137 KB
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nontrivial-unswitch.ll
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; RUN: opt -passes='loop(simple-loop-unswitch<nontrivial>),verify<loops>' -S < %s | FileCheck %s
; RUN: opt -passes='loop-mssa(simple-loop-unswitch<nontrivial>),verify<loops>' -S < %s | FileCheck %s
; RUN: opt -simple-loop-unswitch -enable-nontrivial-unswitch -verify-memoryssa -S < %s | FileCheck %s
declare i32 @a()
declare i32 @b()
declare i32 @c()
declare i32 @d()
declare void @sink1(i32)
declare void @sink2(i32)
declare i1 @cond()
declare i32 @cond.i32()
; Negative test: we cannot unswitch convergent calls.
define void @test_no_unswitch_convergent(i1* %ptr, i1 %cond) {
; CHECK-LABEL: @test_no_unswitch_convergent(
entry:
br label %loop_begin
; CHECK-NEXT: entry:
; CHECK-NEXT: br label %loop_begin
;
; We shouldn't have unswitched into any other block either.
; CHECK-NOT: br i1 %cond
loop_begin:
br i1 %cond, label %loop_a, label %loop_b
; CHECK: loop_begin:
; CHECK-NEXT: br i1 %cond, label %loop_a, label %loop_b
loop_a:
call i32 @a() convergent
br label %loop_latch
loop_b:
call i32 @b()
br label %loop_latch
loop_latch:
%v = load i1, i1* %ptr
br i1 %v, label %loop_begin, label %loop_exit
loop_exit:
ret void
}
; Negative test: we cannot unswitch noduplicate calls.
define void @test_no_unswitch_noduplicate(i1* %ptr, i1 %cond) {
; CHECK-LABEL: @test_no_unswitch_noduplicate(
entry:
br label %loop_begin
; CHECK-NEXT: entry:
; CHECK-NEXT: br label %loop_begin
;
; We shouldn't have unswitched into any other block either.
; CHECK-NOT: br i1 %cond
loop_begin:
br i1 %cond, label %loop_a, label %loop_b
; CHECK: loop_begin:
; CHECK-NEXT: br i1 %cond, label %loop_a, label %loop_b
loop_a:
call i32 @a() noduplicate
br label %loop_latch
loop_b:
call i32 @b()
br label %loop_latch
loop_latch:
%v = load i1, i1* %ptr
br i1 %v, label %loop_begin, label %loop_exit
loop_exit:
ret void
}
declare i32 @__CxxFrameHandler3(...)
; Negative test: we cannot unswitch when tokens are used across blocks as we
; might introduce PHIs.
define void @test_no_unswitch_cross_block_token(i1* %ptr, i1 %cond) nounwind personality i32 (...)* @__CxxFrameHandler3 {
; CHECK-LABEL: @test_no_unswitch_cross_block_token(
entry:
br label %loop_begin
; CHECK-NEXT: entry:
; CHECK-NEXT: br label %loop_begin
;
; We shouldn't have unswitched into any other block either.
; CHECK-NOT: br i1 %cond
loop_begin:
br i1 %cond, label %loop_a, label %loop_b
; CHECK: loop_begin:
; CHECK-NEXT: br i1 %cond, label %loop_a, label %loop_b
loop_a:
call i32 @a()
br label %loop_cont
loop_b:
call i32 @b()
br label %loop_cont
loop_cont:
invoke i32 @a()
to label %loop_latch unwind label %loop_catch
loop_latch:
br label %loop_begin
loop_catch:
%catch = catchswitch within none [label %loop_catch_latch, label %loop_exit] unwind to caller
loop_catch_latch:
%catchpad_latch = catchpad within %catch []
catchret from %catchpad_latch to label %loop_begin
loop_exit:
%catchpad_exit = catchpad within %catch []
catchret from %catchpad_exit to label %exit
exit:
ret void
}
; Non-trivial loop unswitching where there are two distinct trivial conditions
; to unswitch within the loop.
define i32 @test1(i1* %ptr, i1 %cond1, i1 %cond2) {
; CHECK-LABEL: @test1(
entry:
br label %loop_begin
; CHECK-NEXT: entry:
; CHECK-NEXT: br i1 %cond1, label %entry.split.us, label %entry.split
loop_begin:
br i1 %cond1, label %loop_a, label %loop_b
loop_a:
call i32 @a()
br label %latch
; The 'loop_a' unswitched loop.
;
; CHECK: entry.split.us:
; CHECK-NEXT: br label %loop_begin.us
;
; CHECK: loop_begin.us:
; CHECK-NEXT: br label %loop_a.us
;
; CHECK: loop_a.us:
; CHECK-NEXT: call i32 @a()
; CHECK-NEXT: br label %latch.us
;
; CHECK: latch.us:
; CHECK-NEXT: %[[V:.*]] = load i1, i1* %ptr
; CHECK-NEXT: br i1 %[[V]], label %loop_begin.us, label %loop_exit.split.us
;
; CHECK: loop_exit.split.us:
; CHECK-NEXT: br label %loop_exit
loop_b:
br i1 %cond2, label %loop_b_a, label %loop_b_b
; The second unswitched condition.
;
; CHECK: entry.split:
; CHECK-NEXT: br i1 %cond2, label %entry.split.split.us, label %entry.split.split
loop_b_a:
call i32 @b()
br label %latch
; The 'loop_b_a' unswitched loop.
;
; CHECK: entry.split.split.us:
; CHECK-NEXT: br label %loop_begin.us1
;
; CHECK: loop_begin.us1:
; CHECK-NEXT: br label %loop_b.us
;
; CHECK: loop_b.us:
; CHECK-NEXT: br label %loop_b_a.us
;
; CHECK: loop_b_a.us:
; CHECK-NEXT: call i32 @b()
; CHECK-NEXT: br label %latch.us2
;
; CHECK: latch.us2:
; CHECK-NEXT: %[[V:.*]] = load i1, i1* %ptr
; CHECK-NEXT: br i1 %[[V]], label %loop_begin.us1, label %loop_exit.split.split.us
;
; CHECK: loop_exit.split.split.us:
; CHECK-NEXT: br label %loop_exit.split
loop_b_b:
call i32 @c()
br label %latch
; The 'loop_b_b' unswitched loop.
;
; CHECK: entry.split.split:
; CHECK-NEXT: br label %loop_begin
;
; CHECK: loop_begin:
; CHECK-NEXT: br label %loop_b
;
; CHECK: loop_b:
; CHECK-NEXT: br label %loop_b_b
;
; CHECK: loop_b_b:
; CHECK-NEXT: call i32 @c()
; CHECK-NEXT: br label %latch
;
; CHECK: latch:
; CHECK-NEXT: %[[V:.*]] = load i1, i1* %ptr
; CHECK-NEXT: br i1 %[[V]], label %loop_begin, label %loop_exit.split.split
;
; CHECK: loop_exit.split.split:
; CHECK-NEXT: br label %loop_exit.split
latch:
%v = load i1, i1* %ptr
br i1 %v, label %loop_begin, label %loop_exit
loop_exit:
ret i32 0
; CHECK: loop_exit.split:
; CHECK-NEXT: br label %loop_exit
;
; CHECK: loop_exit:
; CHECK-NEXT: ret
}
define i32 @test2(i1* %ptr, i1 %cond1, i32* %a.ptr, i32* %b.ptr, i32* %c.ptr) {
; CHECK-LABEL: @test2(
entry:
br label %loop_begin
; CHECK-NEXT: entry:
; CHECK-NEXT: br i1 %cond1, label %entry.split.us, label %entry.split
loop_begin:
%v = load i1, i1* %ptr
br i1 %cond1, label %loop_a, label %loop_b
loop_a:
%a = load i32, i32* %a.ptr
%ac = load i32, i32* %c.ptr
br i1 %v, label %loop_begin, label %loop_exit
; The 'loop_a' unswitched loop.
;
; CHECK: entry.split.us:
; CHECK-NEXT: br label %loop_begin.us
;
; CHECK: loop_begin.us:
; CHECK-NEXT: %[[V:.*]] = load i1, i1* %ptr
; CHECK-NEXT: br label %loop_a.us
;
; CHECK: loop_a.us:
; CHECK-NEXT: %[[A:.*]] = load i32, i32* %a.ptr
; CHECK-NEXT: %[[AC:.*]] = load i32, i32* %c.ptr
; CHECK-NEXT: br i1 %[[V]], label %loop_begin.backedge.us, label %loop_exit.split.us
;
; CHECK: loop_exit.split.us:
; CHECK-NEXT: %[[A_LCSSA:.*]] = phi i32 [ %[[A]], %loop_a.us ]
; CHECK-NEXT: %[[AC_LCSSA:.*]] = phi i32 [ %[[AC]], %loop_a.us ]
; CHECK-NEXT: br label %loop_exit
loop_b:
%b = load i32, i32* %b.ptr
%bc = load i32, i32* %c.ptr
br i1 %v, label %loop_begin, label %loop_exit
; The 'loop_b' unswitched loop.
;
; CHECK: entry.split:
; CHECK-NEXT: br label %loop_begin
;
; CHECK: loop_begin:
; CHECK-NEXT: %[[V:.*]] = load i1, i1* %ptr
; CHECK-NEXT: br label %loop_b
;
; CHECK: loop_b:
; CHECK-NEXT: %[[B:.*]] = load i32, i32* %b.ptr
; CHECK-NEXT: %[[BC:.*]] = load i32, i32* %c.ptr
; CHECK-NEXT: br i1 %[[V]], label %loop_begin.backedge, label %loop_exit.split
;
; CHECK: loop_exit.split:
; CHECK-NEXT: %[[B_LCSSA:.*]] = phi i32 [ %[[B]], %loop_b ]
; CHECK-NEXT: %[[BC_LCSSA:.*]] = phi i32 [ %[[BC]], %loop_b ]
; CHECK-NEXT: br label %loop_exit
loop_exit:
%ab.phi = phi i32 [ %a, %loop_a ], [ %b, %loop_b ]
%c.phi = phi i32 [ %ac, %loop_a ], [ %bc, %loop_b ]
%result = add i32 %ab.phi, %c.phi
ret i32 %result
; CHECK: loop_exit:
; CHECK-NEXT: %[[AB_PHI:.*]] = phi i32 [ %[[B_LCSSA]], %loop_exit.split ], [ %[[A_LCSSA]], %loop_exit.split.us ]
; CHECK-NEXT: %[[C_PHI:.*]] = phi i32 [ %[[BC_LCSSA]], %loop_exit.split ], [ %[[AC_LCSSA]], %loop_exit.split.us ]
; CHECK-NEXT: %[[RESULT:.*]] = add i32 %[[AB_PHI]], %[[C_PHI]]
; CHECK-NEXT: ret i32 %[[RESULT]]
}
; Test a non-trivial unswitch of an exiting edge to an exit block with other
; in-loop predecessors.
define i32 @test3a(i1* %ptr, i1 %cond1, i32* %a.ptr, i32* %b.ptr) {
; CHECK-LABEL: @test3a(
entry:
br label %loop_begin
; CHECK-NEXT: entry:
; CHECK-NEXT: br i1 %cond1, label %entry.split.us, label %entry.split
loop_begin:
%v = load i1, i1* %ptr
%a = load i32, i32* %a.ptr
br i1 %cond1, label %loop_exit, label %loop_b
; The 'loop_exit' clone.
;
; CHECK: entry.split.us:
; CHECK-NEXT: br label %loop_begin.us
;
; CHECK: loop_begin.us:
; CHECK-NEXT: %[[V:.*]] = load i1, i1* %ptr
; CHECK-NEXT: %[[A:.*]] = load i32, i32* %a.ptr
; CHECK-NEXT: br label %loop_exit.split.us
;
; CHECK: loop_exit.split.us:
; CHECK-NEXT: %[[A_LCSSA:.*]] = phi i32 [ %[[A]], %loop_begin.us ]
; CHECK-NEXT: br label %loop_exit
loop_b:
%b = load i32, i32* %b.ptr
br i1 %v, label %loop_begin, label %loop_exit
; The 'loop_b' unswitched loop.
;
; CHECK: entry.split:
; CHECK-NEXT: br label %loop_begin
;
; CHECK: loop_begin:
; CHECK-NEXT: %[[V:.*]] = load i1, i1* %ptr
; CHECK-NEXT: %[[A:.*]] = load i32, i32* %a.ptr
; CHECK-NEXT: br label %loop_b
;
; CHECK: loop_b:
; CHECK-NEXT: %[[B:.*]] = load i32, i32* %b.ptr
; CHECK-NEXT: br i1 %[[V]], label %loop_begin, label %loop_exit.split
;
; CHECK: loop_exit.split:
; CHECK-NEXT: %[[B_LCSSA:.*]] = phi i32 [ %[[B]], %loop_b ]
; CHECK-NEXT: br label %loop_exit
loop_exit:
%ab.phi = phi i32 [ %a, %loop_begin ], [ %b, %loop_b ]
ret i32 %ab.phi
; CHECK: loop_exit:
; CHECK-NEXT: %[[AB_PHI:.*]] = phi i32 [ %[[B_LCSSA]], %loop_exit.split ], [ %[[A_LCSSA]], %loop_exit.split.us ]
; CHECK-NEXT: ret i32 %[[AB_PHI]]
}
; Test a non-trivial unswitch of an exiting edge to an exit block with other
; in-loop predecessors. This is the same as @test3a but with the reversed order
; of successors so that the exiting edge is *not* the cloned edge.
define i32 @test3b(i1* %ptr, i1 %cond1, i32* %a.ptr, i32* %b.ptr) {
; CHECK-LABEL: @test3b(
entry:
br label %loop_begin
; CHECK-NEXT: entry:
; CHECK-NEXT: br i1 %cond1, label %entry.split.us, label %entry.split
loop_begin:
%v = load i1, i1* %ptr
%a = load i32, i32* %a.ptr
br i1 %cond1, label %loop_b, label %loop_exit
; The 'loop_b' unswitched loop.
;
; CHECK: entry.split.us:
; CHECK-NEXT: br label %loop_begin.us
;
; CHECK: loop_begin.us:
; CHECK-NEXT: %[[V:.*]] = load i1, i1* %ptr
; CHECK-NEXT: %[[A:.*]] = load i32, i32* %a.ptr
; CHECK-NEXT: br label %loop_b.us
;
; CHECK: loop_b.us:
; CHECK-NEXT: %[[B:.*]] = load i32, i32* %b.ptr
; CHECK-NEXT: br i1 %[[V]], label %loop_begin.us, label %loop_exit.split.us
;
; CHECK: loop_exit.split.us:
; CHECK-NEXT: %[[B_LCSSA:.*]] = phi i32 [ %[[B]], %loop_b.us ]
; CHECK-NEXT: br label %loop_exit
loop_b:
%b = load i32, i32* %b.ptr
br i1 %v, label %loop_begin, label %loop_exit
; The original loop, now non-looping due to unswitching..
;
; CHECK: entry.split:
; CHECK-NEXT: br label %loop_begin
;
; CHECK: loop_begin:
; CHECK-NEXT: %[[V:.*]] = load i1, i1* %ptr
; CHECK-NEXT: %[[A:.*]] = load i32, i32* %a.ptr
; CHECK-NEXT: br label %loop_exit.split
;
; CHECK: loop_exit.split:
; CHECK-NEXT: br label %loop_exit
loop_exit:
%ab.phi = phi i32 [ %b, %loop_b ], [ %a, %loop_begin ]
ret i32 %ab.phi
; CHECK: loop_exit:
; CHECK-NEXT: %[[AB_PHI:.*]] = phi i32 [ %[[A]], %loop_exit.split ], [ %[[B_LCSSA]], %loop_exit.split.us ]
; CHECK-NEXT: ret i32 %[[AB_PHI]]
}
; Test a non-trivial unswitch of an exiting edge to an exit block with no other
; in-loop predecessors.
define void @test4a(i1* %ptr, i1 %cond1, i32* %a.ptr, i32* %b.ptr) {
; CHECK-LABEL: @test4a(
entry:
br label %loop_begin
; CHECK-NEXT: entry:
; CHECK-NEXT: br i1 %cond1, label %entry.split.us, label %entry.split
loop_begin:
%v = load i1, i1* %ptr
%a = load i32, i32* %a.ptr
br i1 %cond1, label %loop_exit1, label %loop_b
; The 'loop_exit' clone.
;
; CHECK: entry.split.us:
; CHECK-NEXT: br label %loop_begin.us
;
; CHECK: loop_begin.us:
; CHECK-NEXT: %[[V:.*]] = load i1, i1* %ptr
; CHECK-NEXT: %[[A:.*]] = load i32, i32* %a.ptr
; CHECK-NEXT: br label %loop_exit1.split.us
;
; CHECK: loop_exit1.split.us:
; CHECK-NEXT: %[[A_LCSSA:.*]] = phi i32 [ %[[A]], %loop_begin.us ]
; CHECK-NEXT: br label %loop_exit1
loop_b:
%b = load i32, i32* %b.ptr
br i1 %v, label %loop_begin, label %loop_exit2
; The 'loop_b' unswitched loop.
;
; CHECK: entry.split:
; CHECK-NEXT: br label %loop_begin
;
; CHECK: loop_begin:
; CHECK-NEXT: %[[V:.*]] = load i1, i1* %ptr
; CHECK-NEXT: %[[A:.*]] = load i32, i32* %a.ptr
; CHECK-NEXT: br label %loop_b
;
; CHECK: loop_b:
; CHECK-NEXT: %[[B:.*]] = load i32, i32* %b.ptr
; CHECK-NEXT: br i1 %[[V]], label %loop_begin, label %loop_exit2
loop_exit1:
%a.phi = phi i32 [ %a, %loop_begin ]
call void @sink1(i32 %a.phi)
ret void
; CHECK: loop_exit1:
; CHECK-NEXT: call void @sink1(i32 %[[A_LCSSA]])
; CHECK-NEXT: ret void
loop_exit2:
%b.phi = phi i32 [ %b, %loop_b ]
call void @sink2(i32 %b.phi)
ret void
; CHECK: loop_exit2:
; CHECK-NEXT: %[[B_LCSSA:.*]] = phi i32 [ %[[B]], %loop_b ]
; CHECK-NEXT: call void @sink2(i32 %[[B_LCSSA]])
; CHECK-NEXT: ret void
}
; Test a non-trivial unswitch of an exiting edge to an exit block with no other
; in-loop predecessors. This is the same as @test4a but with the edges reversed
; so that the exiting edge is *not* the cloned edge.
define void @test4b(i1* %ptr, i1 %cond1, i32* %a.ptr, i32* %b.ptr) {
; CHECK-LABEL: @test4b(
entry:
br label %loop_begin
; CHECK-NEXT: entry:
; CHECK-NEXT: br i1 %cond1, label %entry.split.us, label %entry.split
loop_begin:
%v = load i1, i1* %ptr
%a = load i32, i32* %a.ptr
br i1 %cond1, label %loop_b, label %loop_exit1
; The 'loop_b' clone.
;
; CHECK: entry.split.us:
; CHECK-NEXT: br label %loop_begin.us
;
; CHECK: loop_begin.us:
; CHECK-NEXT: %[[V:.*]] = load i1, i1* %ptr
; CHECK-NEXT: %[[A:.*]] = load i32, i32* %a.ptr
; CHECK-NEXT: br label %loop_b.us
;
; CHECK: loop_b.us:
; CHECK-NEXT: %[[B:.*]] = load i32, i32* %b.ptr
; CHECK-NEXT: br i1 %[[V]], label %loop_begin.us, label %loop_exit2.split.us
;
; CHECK: loop_exit2.split.us:
; CHECK-NEXT: %[[B_LCSSA:.*]] = phi i32 [ %[[B]], %loop_b.us ]
; CHECK-NEXT: br label %loop_exit2
loop_b:
%b = load i32, i32* %b.ptr
br i1 %v, label %loop_begin, label %loop_exit2
; The 'loop_exit' unswitched path.
;
; CHECK: entry.split:
; CHECK-NEXT: br label %loop_begin
;
; CHECK: loop_begin:
; CHECK-NEXT: %[[V:.*]] = load i1, i1* %ptr
; CHECK-NEXT: %[[A:.*]] = load i32, i32* %a.ptr
; CHECK-NEXT: br label %loop_exit1
loop_exit1:
%a.phi = phi i32 [ %a, %loop_begin ]
call void @sink1(i32 %a.phi)
ret void
; CHECK: loop_exit1:
; CHECK-NEXT: %[[A_PHI:.*]] = phi i32 [ %[[A]], %loop_begin ]
; CHECK-NEXT: call void @sink1(i32 %[[A_PHI]])
; CHECK-NEXT: ret void
loop_exit2:
%b.phi = phi i32 [ %b, %loop_b ]
call void @sink2(i32 %b.phi)
ret void
; CHECK: loop_exit2:
; CHECK-NEXT: call void @sink2(i32 %[[B_LCSSA]])
; CHECK-NEXT: ret void
}
; Test a non-trivial unswitch of an exiting edge to an exit block with no other
; in-loop predecessors. This is the same as @test4a but with a common merge
; block after the independent loop exits. This requires a different structural
; update to the dominator tree.
define void @test4c(i1* %ptr, i1 %cond1, i32* %a.ptr, i32* %b.ptr) {
; CHECK-LABEL: @test4c(
entry:
br label %loop_begin
; CHECK-NEXT: entry:
; CHECK-NEXT: br i1 %cond1, label %entry.split.us, label %entry.split
loop_begin:
%v = load i1, i1* %ptr
%a = load i32, i32* %a.ptr
br i1 %cond1, label %loop_exit1, label %loop_b
; The 'loop_exit' clone.
;
; CHECK: entry.split.us:
; CHECK-NEXT: br label %loop_begin.us
;
; CHECK: loop_begin.us:
; CHECK-NEXT: %[[V:.*]] = load i1, i1* %ptr
; CHECK-NEXT: %[[A:.*]] = load i32, i32* %a.ptr
; CHECK-NEXT: br label %loop_exit1.split.us
;
; CHECK: loop_exit1.split.us:
; CHECK-NEXT: %[[A_LCSSA:.*]] = phi i32 [ %[[A]], %loop_begin.us ]
; CHECK-NEXT: br label %loop_exit1
loop_b:
%b = load i32, i32* %b.ptr
br i1 %v, label %loop_begin, label %loop_exit2
; The 'loop_b' unswitched loop.
;
; CHECK: entry.split:
; CHECK-NEXT: br label %loop_begin
;
; CHECK: loop_begin:
; CHECK-NEXT: %[[V:.*]] = load i1, i1* %ptr
; CHECK-NEXT: %[[A:.*]] = load i32, i32* %a.ptr
; CHECK-NEXT: br label %loop_b
;
; CHECK: loop_b:
; CHECK-NEXT: %[[B:.*]] = load i32, i32* %b.ptr
; CHECK-NEXT: br i1 %[[V]], label %loop_begin, label %loop_exit2
loop_exit1:
%a.phi = phi i32 [ %a, %loop_begin ]
call void @sink1(i32 %a.phi)
br label %exit
; CHECK: loop_exit1:
; CHECK-NEXT: call void @sink1(i32 %[[A_LCSSA]])
; CHECK-NEXT: br label %exit
loop_exit2:
%b.phi = phi i32 [ %b, %loop_b ]
call void @sink2(i32 %b.phi)
br label %exit
; CHECK: loop_exit2:
; CHECK-NEXT: %[[B_LCSSA:.*]] = phi i32 [ %[[B]], %loop_b ]
; CHECK-NEXT: call void @sink2(i32 %[[B_LCSSA]])
; CHECK-NEXT: br label %exit
exit:
ret void
; CHECK: exit:
; CHECK-NEXT: ret void
}
; Test that we can unswitch a condition out of multiple layers of a loop nest.
define i32 @test5(i1* %ptr, i1 %cond1, i32* %a.ptr, i32* %b.ptr) {
; CHECK-LABEL: @test5(
entry:
br label %loop_begin
; CHECK-NEXT: entry:
; CHECK-NEXT: br i1 %cond1, label %loop_begin.split.us, label %entry.split
;
; CHECK: entry.split:
; CHECK-NEXT: br label %loop_begin
;
; CHECK: loop_begin:
; CHECK-NEXT: br label %loop_begin.split
loop_begin:
br label %inner_loop_begin
inner_loop_begin:
%v = load i1, i1* %ptr
%a = load i32, i32* %a.ptr
br i1 %cond1, label %loop_exit, label %inner_loop_b
; The 'loop_exit' clone.
;
; CHECK: loop_begin.split.us:
; CHECK-NEXT: br label %inner_loop_begin.us
;
; CHECK: inner_loop_begin.us:
; CHECK-NEXT: %[[V:.*]] = load i1, i1* %ptr
; CHECK-NEXT: %[[A:.*]] = load i32, i32* %a.ptr
; CHECK-NEXT: br label %loop_exit.loopexit.split.us
;
; CHECK: loop_exit.loopexit.split.us:
; CHECK-NEXT: %[[A_LCSSA:.*]] = phi i32 [ %[[A]], %inner_loop_begin.us ]
; CHECK-NEXT: br label %loop_exit
inner_loop_b:
%b = load i32, i32* %b.ptr
br i1 %v, label %inner_loop_begin, label %loop_latch
; The 'inner_loop_b' unswitched loop.
;
; CHECK: loop_begin.split:
; CHECK-NEXT: br label %inner_loop_begin
;
; CHECK: inner_loop_begin:
; CHECK-NEXT: %[[V:.*]] = load i1, i1* %ptr
; CHECK-NEXT: %[[A:.*]] = load i32, i32* %a.ptr
; CHECK-NEXT: br label %inner_loop_b
;
; CHECK: inner_loop_b:
; CHECK-NEXT: %[[B:.*]] = load i32, i32* %b.ptr
; CHECK-NEXT: br i1 %[[V]], label %inner_loop_begin, label %loop_latch
loop_latch:
%b.phi = phi i32 [ %b, %inner_loop_b ]
%v2 = load i1, i1* %ptr
br i1 %v2, label %loop_begin, label %loop_exit
; CHECK: loop_latch:
; CHECK-NEXT: %[[B_INNER_LCSSA:.*]] = phi i32 [ %[[B]], %inner_loop_b ]
; CHECK-NEXT: %[[V2:.*]] = load i1, i1* %ptr
; CHECK-NEXT: br i1 %[[V2]], label %loop_begin, label %loop_exit.loopexit1
loop_exit:
%ab.phi = phi i32 [ %a, %inner_loop_begin ], [ %b.phi, %loop_latch ]
ret i32 %ab.phi
; CHECK: loop_exit.loopexit:
; CHECK-NEXT: br label %loop_exit
;
; CHECK: loop_exit.loopexit1:
; CHECK-NEXT: %[[B_LCSSA:.*]] = phi i32 [ %[[B_INNER_LCSSA]], %loop_latch ]
; CHECK-NEXT: br label %loop_exit
;
; CHECK: loop_exit:
; CHECK-NEXT: %[[AB_PHI:.*]] = phi i32 [ %[[A_LCSSA]], %loop_exit.loopexit ], [ %[[B_LCSSA]], %loop_exit.loopexit1 ]
; CHECK-NEXT: ret i32 %[[AB_PHI]]
}
; Test that we can unswitch a condition where we end up only cloning some of
; the nested loops and needing to delete some of the nested loops.
define i32 @test6(i1* %ptr, i1 %cond1, i32* %a.ptr, i32* %b.ptr) {
; CHECK-LABEL: @test6(
entry:
br label %loop_begin
; CHECK-NEXT: entry:
; CHECK-NEXT: br i1 %cond1, label %entry.split.us, label %entry.split
loop_begin:
%v = load i1, i1* %ptr
br i1 %cond1, label %loop_a, label %loop_b
loop_a:
br label %loop_a_inner
loop_a_inner:
%va = load i1, i1* %ptr
%a = load i32, i32* %a.ptr
br i1 %va, label %loop_a_inner, label %loop_a_inner_exit
loop_a_inner_exit:
%a.lcssa = phi i32 [ %a, %loop_a_inner ]
br label %latch
; The 'loop_a' cloned loop.
;
; CHECK: entry.split.us:
; CHECK-NEXT: br label %loop_begin.us
;
; CHECK: loop_begin.us:
; CHECK-NEXT: %[[V:.*]] = load i1, i1* %ptr
; CHECK-NEXT: br label %loop_a.us
;
; CHECK: loop_a.us:
; CHECK-NEXT: br label %loop_a_inner.us
;
; CHECK: loop_a_inner.us
; CHECK-NEXT: %[[VA:.*]] = load i1, i1* %ptr
; CHECK-NEXT: %[[A:.*]] = load i32, i32* %a.ptr
; CHECK-NEXT: br i1 %[[VA]], label %loop_a_inner.us, label %loop_a_inner_exit.us
;
; CHECK: loop_a_inner_exit.us:
; CHECK-NEXT: %[[A_INNER_LCSSA:.*]] = phi i32 [ %[[A]], %loop_a_inner.us ]
; CHECK-NEXT: br label %latch.us
;
; CHECK: latch.us:
; CHECK-NEXT: %[[A_PHI:.*]] = phi i32 [ %[[A_INNER_LCSSA]], %loop_a_inner_exit.us ]
; CHECK-NEXT: br i1 %[[V]], label %loop_begin.us, label %loop_exit.split.us
;
; CHECK: loop_exit.split.us:
; CHECK-NEXT: %[[A_LCSSA:.*]] = phi i32 [ %[[A_PHI]], %latch.us ]
; CHECK-NEXT: br label %loop_exit
loop_b:
br label %loop_b_inner
loop_b_inner:
%vb = load i1, i1* %ptr
%b = load i32, i32* %b.ptr
br i1 %vb, label %loop_b_inner, label %loop_b_inner_exit
loop_b_inner_exit:
%b.lcssa = phi i32 [ %b, %loop_b_inner ]
br label %latch
latch:
%ab.phi = phi i32 [ %a.lcssa, %loop_a_inner_exit ], [ %b.lcssa, %loop_b_inner_exit ]
br i1 %v, label %loop_begin, label %loop_exit
; The 'loop_b' unswitched loop.
;
; CHECK: entry.split:
; CHECK-NEXT: br label %loop_begin
;
; CHECK: loop_begin:
; CHECK-NEXT: %[[V:.*]] = load i1, i1* %ptr
; CHECK-NEXT: br label %loop_b
;
; CHECK: loop_b:
; CHECK-NEXT: br label %loop_b_inner
;
; CHECK: loop_b_inner
; CHECK-NEXT: %[[VB:.*]] = load i1, i1* %ptr
; CHECK-NEXT: %[[B:.*]] = load i32, i32* %b.ptr
; CHECK-NEXT: br i1 %[[VB]], label %loop_b_inner, label %loop_b_inner_exit
;
; CHECK: loop_b_inner_exit:
; CHECK-NEXT: %[[B_INNER_LCSSA:.*]] = phi i32 [ %[[B]], %loop_b_inner ]
; CHECK-NEXT: br label %latch
;
; CHECK: latch:
; CHECK-NEXT: br i1 %[[V]], label %loop_begin, label %loop_exit.split
;
; CHECK: loop_exit.split:
; CHECK-NEXT: %[[B_LCSSA:.*]] = phi i32 [ %[[B_INNER_LCSSA]], %latch ]
; CHECK-NEXT: br label %loop_exit
loop_exit:
%ab.lcssa = phi i32 [ %ab.phi, %latch ]
ret i32 %ab.lcssa
; CHECK: loop_exit:
; CHECK-NEXT: %[[AB_PHI:.*]] = phi i32 [ %[[B_LCSSA]], %loop_exit.split ], [ %[[A_LCSSA]], %loop_exit.split.us ]
; CHECK-NEXT: ret i32 %[[AB_PHI]]
}
; Test that when unswitching a deeply nested loop condition in a way that
; produces a non-loop clone that can reach multiple exit blocks which are part
; of different outer loops we correctly divide the cloned loop blocks between
; the outer loops based on reachability.
define i32 @test7a(i1* %ptr, i1* %cond.ptr, i32* %a.ptr, i32* %b.ptr) {
; CHECK-LABEL: @test7a(
entry:
br label %loop_begin
; CHECK-NEXT: entry:
; CHECK-NEXT: br label %loop_begin
loop_begin:
%a = load i32, i32* %a.ptr
br label %inner_loop_begin
; CHECK: loop_begin:
; CHECK-NEXT: %[[A:.*]] = load i32, i32* %a.ptr
; CHECK-NEXT: br label %inner_loop_begin
inner_loop_begin:
%a.phi = phi i32 [ %a, %loop_begin ], [ %a2, %inner_inner_loop_exit ]
%cond = load i1, i1* %cond.ptr
%b = load i32, i32* %b.ptr
br label %inner_inner_loop_begin
; CHECK: inner_loop_begin:
; CHECK-NEXT: %[[A_INNER_PHI:.*]] = phi i32 [ %[[A]], %loop_begin ], [ %[[A2:.*]], %inner_inner_loop_exit ]
; CHECK-NEXT: %[[COND:.*]] = load i1, i1* %cond.ptr
; CHECK-NEXT: %[[B:.*]] = load i32, i32* %b.ptr
; CHECK-NEXT: %[[FROZEN:.+]] = freeze i1 %[[COND]]
; CHECK-NEXT: br i1 %[[FROZEN]], label %inner_loop_begin.split.us, label %inner_loop_begin.split
inner_inner_loop_begin:
%v1 = load i1, i1* %ptr
br i1 %v1, label %inner_inner_loop_a, label %inner_inner_loop_b
inner_inner_loop_a:
%v2 = load i1, i1* %ptr
br i1 %v2, label %loop_exit, label %inner_inner_loop_c
inner_inner_loop_b:
%v3 = load i1, i1* %ptr
br i1 %v3, label %inner_inner_loop_exit, label %inner_inner_loop_c
inner_inner_loop_c:
%v4 = load i1, i1* %ptr
br i1 %v4, label %inner_loop_exit, label %inner_inner_loop_d
inner_inner_loop_d:
br i1 %cond, label %inner_loop_exit, label %inner_inner_loop_begin
; The cloned copy that always exits with the adjustments required to fix up
; loop exits.
;
; CHECK: inner_loop_begin.split.us:
; CHECK-NEXT: br label %inner_inner_loop_begin.us
;
; CHECK: inner_inner_loop_begin.us:
; CHECK-NEXT: %[[V:.*]] = load i1, i1* %ptr
; CHECK-NEXT: br i1 %[[V]], label %inner_inner_loop_a.us, label %inner_inner_loop_b.us
;
; CHECK: inner_inner_loop_b.us:
; CHECK-NEXT: %[[V:.*]] = load i1, i1* %ptr
; CHECK-NEXT: br i1 %[[V]], label %inner_inner_loop_exit.split.us, label %inner_inner_loop_c.us.loopexit
;
; CHECK: inner_inner_loop_a.us:
; CHECK-NEXT: %[[A_NEW_LCSSA:.*]] = phi i32 [ %[[A_INNER_PHI]], %inner_inner_loop_begin.us ]
; CHECK-NEXT: %[[B_NEW_LCSSA:.*]] = phi i32 [ %[[B]], %inner_inner_loop_begin.us ]
; CHECK-NEXT: %[[V:.*]] = load i1, i1* %ptr
; CHECK-NEXT: br i1 %[[V]], label %loop_exit.split.us, label %inner_inner_loop_c.us
;
; CHECK: inner_inner_loop_c.us.loopexit:
; CHECK-NEXT: br label %inner_inner_loop_c.us
;
; CHECK: inner_inner_loop_c.us:
; CHECK-NEXT: %[[V:.*]] = load i1, i1* %ptr
; CHECK-NEXT: br i1 %[[V]], label %inner_loop_exit.loopexit.split.us, label %inner_inner_loop_d.us
;
; CHECK: inner_inner_loop_d.us:
; CHECK-NEXT: br label %inner_loop_exit.loopexit.split
;
; CHECK: inner_inner_loop_exit.split.us:
; CHECK-NEXT: br label %inner_inner_loop_exit
;
; CHECK: loop_exit.split.us:
; CHECK-NEXT: %[[A_LCSSA_US:.*]] = phi i32 [ %[[A_NEW_LCSSA]], %inner_inner_loop_a.us ]
; CHECK-NEXT: %[[B_LCSSA_US:.*]] = phi i32 [ %[[B_NEW_LCSSA]], %inner_inner_loop_a.us ]
; CHECK-NEXT: br label %loop_exit
;
; CHECK: inner_loop_exit.loopexit.split.us:
; CHECK-NEXT: br label %inner_loop_exit.loopexit
;
; The original copy that continues to loop.
;
; CHECK: inner_loop_begin.split:
; CHECK-NEXT: br label %inner_inner_loop_begin
;
; CHECK: inner_inner_loop_begin:
; CHECK-NEXT: %[[V:.*]] = load i1, i1* %ptr
; CHECK-NEXT: br i1 %[[V]], label %inner_inner_loop_a, label %inner_inner_loop_b
;
; CHECK: inner_inner_loop_a:
; CHECK-NEXT: %[[V:.*]] = load i1, i1* %ptr
; CHECK-NEXT: br i1 %[[V]], label %loop_exit.split, label %inner_inner_loop_c
;
; CHECK: inner_inner_loop_b:
; CHECK-NEXT: %[[V:.*]] = load i1, i1* %ptr
; CHECK-NEXT: br i1 %[[V]], label %inner_inner_loop_exit.split, label %inner_inner_loop_c
;
; CHECK: inner_inner_loop_c:
; CHECK-NEXT: %[[V:.*]] = load i1, i1* %ptr
; CHECK-NEXT: br i1 %[[V]], label %inner_loop_exit.loopexit.split, label %inner_inner_loop_d
;
; CHECK: inner_inner_loop_d:
; CHECK-NEXT: br label %inner_inner_loop_begin
;
; CHECK: inner_inner_loop_exit.split:
; CHECK-NEXT: br label %inner_inner_loop_exit
inner_inner_loop_exit:
%a2 = load i32, i32* %a.ptr
%v5 = load i1, i1* %ptr
br i1 %v5, label %inner_loop_exit, label %inner_loop_begin
; CHECK: inner_inner_loop_exit:
; CHECK-NEXT: %[[A2]] = load i32, i32* %a.ptr
; CHECK-NEXT: %[[V:.*]] = load i1, i1* %ptr
; CHECK-NEXT: br i1 %[[V]], label %inner_loop_exit.loopexit1, label %inner_loop_begin
inner_loop_exit:
br label %loop_begin
; CHECK: inner_loop_exit.loopexit.split:
; CHECK-NEXT: br label %inner_loop_exit.loopexit
;
; CHECK: inner_loop_exit.loopexit:
; CHECK-NEXT: br label %inner_loop_exit
;
; CHECK: inner_loop_exit.loopexit1:
; CHECK-NEXT: br label %inner_loop_exit
;
; CHECK: inner_loop_exit:
; CHECK-NEXT: br label %loop_begin
loop_exit:
%a.lcssa = phi i32 [ %a.phi, %inner_inner_loop_a ]
%b.lcssa = phi i32 [ %b, %inner_inner_loop_a ]
%result = add i32 %a.lcssa, %b.lcssa
ret i32 %result
; CHECK: loop_exit.split:
; CHECK-NEXT: %[[A_LCSSA:.*]] = phi i32 [ %[[A_INNER_PHI]], %inner_inner_loop_a ]
; CHECK-NEXT: %[[B_LCSSA:.*]] = phi i32 [ %[[B]], %inner_inner_loop_a ]
; CHECK-NEXT: br label %loop_exit
;
; CHECK: loop_exit:
; CHECK-NEXT: %[[A_PHI:.*]] = phi i32 [ %[[A_LCSSA]], %loop_exit.split ], [ %[[A_LCSSA_US]], %loop_exit.split.us ]
; CHECK-NEXT: %[[B_PHI:.*]] = phi i32 [ %[[B_LCSSA]], %loop_exit.split ], [ %[[B_LCSSA_US]], %loop_exit.split.us ]
; CHECK-NEXT: %[[RESULT:.*]] = add i32 %[[A_PHI]], %[[B_PHI]]
; CHECK-NEXT: ret i32 %[[RESULT]]
}
; Same pattern as @test7a but here the original loop becomes a non-loop that
; can reach multiple exit blocks which are part of different outer loops.
define i32 @test7b(i1* %ptr, i1* %cond.ptr, i32* %a.ptr, i32* %b.ptr) {
; CHECK-LABEL: @test7b(
entry:
br label %loop_begin
; CHECK-NEXT: entry:
; CHECK-NEXT: br label %loop_begin
loop_begin:
%a = load i32, i32* %a.ptr
br label %inner_loop_begin
; CHECK: loop_begin:
; CHECK-NEXT: %[[A:.*]] = load i32, i32* %a.ptr
; CHECK-NEXT: br label %inner_loop_begin
inner_loop_begin:
%a.phi = phi i32 [ %a, %loop_begin ], [ %a2, %inner_inner_loop_exit ]
%cond = load i1, i1* %cond.ptr
%b = load i32, i32* %b.ptr
br label %inner_inner_loop_begin
; CHECK: inner_loop_begin:
; CHECK-NEXT: %[[A_INNER_PHI:.*]] = phi i32 [ %[[A]], %loop_begin ], [ %[[A2:.*]], %inner_inner_loop_exit ]
; CHECK-NEXT: %[[COND:.*]] = load i1, i1* %cond.ptr
; CHECK-NEXT: %[[B:.*]] = load i32, i32* %b.ptr
; CHECK-NEXT: %[[FROZEN:.+]] = freeze i1 %[[COND]]
; CHECK-NEXT: br i1 %[[FROZEN]], label %inner_loop_begin.split.us, label %inner_loop_begin.split
inner_inner_loop_begin:
%v1 = load i1, i1* %ptr
br i1 %v1, label %inner_inner_loop_a, label %inner_inner_loop_b
inner_inner_loop_a:
%v2 = load i1, i1* %ptr
br i1 %v2, label %loop_exit, label %inner_inner_loop_c
inner_inner_loop_b:
%v3 = load i1, i1* %ptr
br i1 %v3, label %inner_inner_loop_exit, label %inner_inner_loop_c
inner_inner_loop_c:
%v4 = load i1, i1* %ptr
br i1 %v4, label %inner_loop_exit, label %inner_inner_loop_d
inner_inner_loop_d:
br i1 %cond, label %inner_inner_loop_begin, label %inner_loop_exit
; The cloned copy that continues looping.
;
; CHECK: inner_loop_begin.split.us:
; CHECK-NEXT: br label %inner_inner_loop_begin.us
;
; CHECK: inner_inner_loop_begin.us:
; CHECK-NEXT: %[[V:.*]] = load i1, i1* %ptr
; CHECK-NEXT: br i1 %[[V]], label %inner_inner_loop_a.us, label %inner_inner_loop_b.us
;
; CHECK: inner_inner_loop_b.us: