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|
; RUN: opt -disable-output -passes=loop-unroll -debug-only=loop-unroll < %s 2>&1 | FileCheck %s --match-full-lines --strict-whitespace
; REQUIRES: asserts
; CHECK-LABEL:Loop Unroll: F[pragma_full_unroll_unknown_tc] Loop %for.body
; CHECK-NEXT:Loop Size = 6
; CHECK-NEXT: Will not try to unroll loop with runtime trip count because -unroll-runtime not given
define i32 @pragma_full_unroll_unknown_tc(ptr %A, i32 %n) {
entry:
%cmp.entry = icmp sgt i32 %n, 0
br i1 %cmp.entry, label %for.body, label %exit
for.body:
%i = phi i32 [ 0, %entry ], [ %inc, %for.body ]
%sum = phi i32 [ 0, %entry ], [ %add, %for.body ]
%arrayidx = getelementptr inbounds i32, ptr %A, i32 %i
%load = load i32, ptr %arrayidx
%add = add i32 %sum, %load
%inc = add i32 %i, 1
%cmp = icmp slt i32 %inc, %n
br i1 %cmp, label %for.body, label %exit, !llvm.loop !0
exit:
%result = phi i32 [ 0, %entry ], [ %add, %for.body ]
ret i32 %result
}
; CHECK-LABEL:Loop Unroll: F[full_unroll_cost_exceeds] Loop %for.body
; CHECK-NEXT:Loop Size = 6
; CHECK-NEXT: Will not try to unroll partially because -unroll-allow-partial not given
define i32 @full_unroll_cost_exceeds(ptr %A) {
entry:
br label %for.body
for.body:
%i = phi i32 [ 0, %entry ], [ %inc, %for.body ]
%sum = phi i32 [ 0, %entry ], [ %add, %for.body ]
%arrayidx = getelementptr inbounds i32, ptr %A, i32 %i
%load = load i32, ptr %arrayidx
%add = add i32 %sum, %load
%inc = add i32 %i, 1
%cmp = icmp ult i32 %inc, 100
br i1 %cmp, label %for.body, label %exit
exit:
ret i32 %add
}
; CHECK-LABEL:Loop Unroll: F[extended_convergence] Loop %for.body
; CHECK-NEXT: Not unrolling: contains convergent operations.
declare void @convergent_func() convergent
declare token @llvm.experimental.convergence.anchor()
define i32 @extended_convergence(ptr %A, i32 %n) {
entry:
br label %for.body, !llvm.loop !1
for.body:
%i = phi i32 [ 0, %entry ], [ %inc, %for.body ]
%sum = phi i32 [ 0, %entry ], [ %add, %for.body ]
%tok = call token @llvm.experimental.convergence.anchor()
%arrayidx = getelementptr inbounds i32, ptr %A, i32 %i
%load = load i32, ptr %arrayidx
%add = add i32 %sum, %load
%inc = add i32 %i, 1
%cmp = icmp slt i32 %inc, %n
br i1 %cmp, label %for.body, label %exit, !llvm.loop !1
exit:
call void @convergent_func() [ "convergencectrl"(token %tok) ]
ret i32 %add
}
; CHECK-LABEL:Loop Unroll: F[noduplicate_prevents_unroll] Loop %for.body
; CHECK-NEXT: Not unrolling: contains non-duplicatable instructions.
declare void @noduplicate_func() noduplicate
define i32 @noduplicate_prevents_unroll(ptr %A) {
entry:
br label %for.body
for.body:
%i = phi i32 [ 0, %entry ], [ %inc, %for.body ]
%sum = phi i32 [ 0, %entry ], [ %add, %for.body ]
%arrayidx = getelementptr inbounds i32, ptr %A, i32 %i
%load = load i32, ptr %arrayidx
call void @noduplicate_func()
%add = add i32 %sum, %load
%inc = add i32 %i, 1
%cmp = icmp ult i32 %inc, 8
br i1 %cmp, label %for.body, label %exit, !llvm.loop !1
exit:
ret i32 %add
}
; CHECK-LABEL:Loop Unroll: F[indirectbr_loop] Loop %for.body
; CHECK-NEXT: Not unrolling loop which is not in loop-simplify form.
define i32 @indirectbr_loop(ptr %A, ptr %target) {
entry:
indirectbr ptr %target, [label %for.body, label %exit]
for.body:
%i = phi i32 [ 0, %entry ], [ %inc, %for.body ]
%sum = phi i32 [ 0, %entry ], [ %add, %for.body ]
%arrayidx = getelementptr inbounds i32, ptr %A, i32 %i
%load = load i32, ptr %arrayidx
%add = add i32 %sum, %load
%inc = add i32 %i, 1
%cmp = icmp ult i32 %inc, 10
br i1 %cmp, label %for.body, label %exit, !llvm.loop !1
exit:
%result = phi i32 [ 0, %entry ], [ %add, %for.body ]
ret i32 %result
}
; CHECK-LABEL:Loop Unroll: F[inline_prevents_unroll] Loop %for.body
; CHECK-NEXT:Loop Size = 8
; CHECK-NEXT: Not unrolling loop with inlinable calls.
define internal i32 @single_use_helper(i32 %x) {
%add = add i32 %x, 42
ret i32 %add
}
define i32 @inline_prevents_unroll(ptr %A) {
entry:
br label %for.body
for.body:
%i = phi i32 [ 0, %entry ], [ %inc, %for.body ]
%sum = phi i32 [ 0, %entry ], [ %add, %for.body ]
%arrayidx = getelementptr inbounds i32, ptr %A, i32 %i
%load = load i32, ptr %arrayidx
%helper_result = call i32 @single_use_helper(i32 %load)
%add = add i32 %sum, %helper_result
%inc = add i32 %i, 1
%cmp = icmp ult i32 %inc, 10
br i1 %cmp, label %for.body, label %exit, !llvm.loop !2
exit:
ret i32 %add
}
; CHECK-LABEL:Loop Unroll: F[full_unroll_profitability_analysis] Loop %for.body
; CHECK-NEXT:Loop Size = {{[0-9]+}}
; CHECK-NEXT: Starting LoopUnroll profitability analysis...
; CHECK-NEXT: Analyzing iteration 0
; CHECK-NEXT: Analyzing iteration 1
; CHECK-NEXT: Analyzing iteration 2
; CHECK-NEXT: Analyzing iteration 3
; CHECK-NEXT: Analyzing iteration 4
; CHECK-NEXT: Analyzing iteration 5
; CHECK-NEXT: Analyzing iteration 6
; CHECK-NEXT: Analyzing iteration 7
; CHECK-NEXT: Analyzing iteration 8
; CHECK-NEXT: Analyzing iteration 9
; CHECK: Analysis finished:
; CHECK-NEXT: UnrolledCost: {{[0-9]+}}, RolledDynamicCost: {{[0-9]+}}
; CHECK-NEXT: Exiting block %for.body: TripCount=10, TripMultiple=0, BreakoutTrip=0
; CHECK-NEXT:COMPLETELY UNROLLING loop %for.body with trip count 10!
define i32 @full_unroll_profitability_analysis(ptr %A, ptr %B) {
entry:
br label %for.body
for.body:
%i = phi i32 [ 0, %entry ], [ %inc, %for.body ]
%sum = phi i32 [ 0, %entry ], [ %result, %for.body ]
%idxA = getelementptr inbounds i32, ptr %A, i32 %i
%loadA = load i32, ptr %idxA
%idxB = getelementptr inbounds i32, ptr %B, i32 %i
%loadB = load i32, ptr %idxB
%mul1 = mul i32 %loadA, %loadB
%add1 = add i32 %mul1, %loadA
%mul2 = mul i32 %add1, %loadB
%sub1 = sub i32 %mul2, %loadA
%add2 = add i32 %sub1, %loadB
%mul3 = mul i32 %add2, %loadA
%sub2 = sub i32 %mul3, %loadB
%xor1 = xor i32 %sub2, %loadA
%or1 = or i32 %xor1, %loadB
%result = add i32 %sum, %or1
%inc = add i32 %i, 1
%cmp = icmp ult i32 %inc, 10
br i1 %cmp, label %for.body, label %exit
exit:
ret i32 %result
}
!0 = distinct !{!0, !3}
!1 = distinct !{!1, !4}
!2 = distinct !{!2, !4}
!3 = !{!"llvm.loop.unroll.full"}
!4 = !{!"llvm.loop.unroll.enable"}
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