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; RUN: opt < %s -passes=loop-predication -S | FileCheck %s
; RUN: opt -S -passes='require<scalar-evolution>,loop-mssa(loop-predication)' -verify-memoryssa < %s 2>&1 | FileCheck %s
;; This is a simplified copy of @unswitch_exit_form test that should trigger loop-predication
;; activity and properly bail out when discovering that widenable check does not lead to deopt.
;;
;; Error checking is rather silly here - it should pass compilation successfully,
;; in bad case it will just timeout.
;;
define i32 @unswitch_exit_form_with_endless_loop(ptr %array, i32 %length, i32 %n, i1 %cond_0) {
; CHECK-LABEL: @unswitch_exit_form_with_endless_loop
entry:
%widenable_cond = call i1 @llvm.experimental.widenable.condition()
%exiplicit_guard_cond = and i1 %cond_0, %widenable_cond
br i1 %exiplicit_guard_cond, label %loop.preheader, label %not_really_a_deopt, !prof !0
not_really_a_deopt:
br label %looping
looping:
;; synthetic corner case that demonstrates the need for more careful traversal
;; of unique successors when walking through the exit for profitability checks.
br label %looping
loop.preheader:
br label %loop
loop:
%loop.acc = phi i32 [ %loop.acc.next, %guarded ], [ 0, %loop.preheader ]
%i = phi i32 [ %i.next, %guarded ], [ 0, %loop.preheader ]
%within.bounds = icmp ult i32 %i, %length
br i1 %within.bounds, label %guarded, label %not_really_a_deopt, !prof !0
guarded:
%i.i64 = zext i32 %i to i64
%array.i.ptr = getelementptr inbounds i32, ptr %array, i64 %i.i64
%array.i = load i32, ptr %array.i.ptr, align 4
store i32 0, ptr %array.i.ptr
%loop.acc.next = add i32 %loop.acc, %array.i
%i.next = add nuw i32 %i, 1
%continue = icmp ult i32 %i.next, %n
br i1 %continue, label %loop, label %exit
exit:
%result = phi i32 [ %loop.acc.next, %guarded ]
ret i32 %result
}
declare void @unknown()
declare i1 @llvm.experimental.widenable.condition()
declare i32 @llvm.experimental.deoptimize.i32(...)
!0 = !{!"branch_weights", i32 1048576, i32 1}
!1 = !{i32 1, i32 -2147483648}
!2 = !{i32 0, i32 50}
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