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