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;
; Here all the branches we unswitch are exiting from the inner loop.
; That means we should not be getting exponential behavior on inner-loop
; unswitch. In fact there should be just a single version of inner-loop,
; with possibly some outer loop copies.
;
; There should be just a single copy of each loop when strictest mutiplier
; candidates formula (unscaled candidates == 0) is enforced:
; RUN: opt < %s -enable-unswitch-cost-multiplier=true \
; RUN: -unswitch-num-initial-unscaled-candidates=0 -unswitch-siblings-toplevel-div=1 \
; RUN: -passes='loop(simple-loop-unswitch<nontrivial>),print<loops>' -disable-output 2>&1 | FileCheck %s --check-prefixes=LOOP1
;
; RUN: opt < %s -enable-unswitch-cost-multiplier=true \
; RUN: -unswitch-num-initial-unscaled-candidates=0 -unswitch-siblings-toplevel-div=16 \
; RUN: -passes='loop(simple-loop-unswitch<nontrivial>),print<loops>' -disable-output 2>&1 | FileCheck %s --check-prefixes=LOOP1
;
; RUN: opt < %s -enable-unswitch-cost-multiplier=true \
; RUN: -unswitch-num-initial-unscaled-candidates=0 -unswitch-siblings-toplevel-div=1 \
; RUN: -passes='loop-mssa(simple-loop-unswitch<nontrivial>),print<loops>' -disable-output 2>&1 | FileCheck %s --check-prefixes=LOOP1
;
; RUN: opt < %s -enable-unswitch-cost-multiplier=true \
; RUN: -unswitch-num-initial-unscaled-candidates=0 -unswitch-siblings-toplevel-div=16 \
; RUN: -passes='loop-mssa(simple-loop-unswitch<nontrivial>),print<loops>' -disable-output 2>&1 | FileCheck %s --check-prefixes=LOOP1
;
; When we relax the candidates part of a multiplier formula
; (unscaled candidates == 2) we start getting some unswitches in outer loops,
; which leads to siblings multiplier kicking in.
;
; The tests below also run licm, because it is needed to hoist out
; loop-invariant freeze instructions, which otherwise may block further
; unswitching.
;
; RUN: opt < %s -enable-unswitch-cost-multiplier=true \
; RUN: -unswitch-num-initial-unscaled-candidates=3 -unswitch-siblings-toplevel-div=1 \
; RUN: -passes='loop-mssa(licm,simple-loop-unswitch<nontrivial>),print<loops>' -disable-output 2>&1 | \
; RUN: sort -b -k 1 | FileCheck %s --check-prefixes=LOOP-UNSCALE3-DIV1
;
; NB: sort -b is essential here and below, otherwise blanks might lead to different
; order depending on locale.
;
; RUN: opt < %s -enable-unswitch-cost-multiplier=true \
; RUN: -unswitch-num-initial-unscaled-candidates=3 -unswitch-siblings-toplevel-div=2 \
; RUN: -passes='loop-mssa(licm,simple-loop-unswitch<nontrivial>),print<loops>' -disable-output 2>&1 | \
; RUN: sort -b -k 1 | FileCheck %s --check-prefixes=LOOP-UNSCALE3-DIV2
;
; With disabled cost-multiplier we get maximal possible amount of unswitches.
;
; RUN: opt < %s -enable-unswitch-cost-multiplier=false \
; RUN: -passes='loop-mssa(licm,simple-loop-unswitch<nontrivial>),print<loops>' -disable-output 2>&1 | \
; RUN: sort -b -k 1 | FileCheck %s --check-prefixes=LOOP-MAX
;
; Single loop nest, not unswitched
; LOOP1: Loop at depth 1 containing:
; LOOP1-NOT: Loop at depth 1 containing:
; LOOP1: Loop at depth 2 containing:
; LOOP1-NOT: Loop at depth 2 containing:
; LOOP1: Loop at depth 3 containing:
; LOOP1-NOT: Loop at depth 3 containing:
;
; Half unswitched loop nests, with unscaled3 and div1 it gets less depth1 loops unswitched
; since they have more cost.
; LOOP-UNSCALE3-DIV1-COUNT-4: Loop at depth 1 containing:
; LOOP-UNSCALE3-DIV1-NOT: Loop at depth 1 containing:
; LOOP-UNSCALE3-DIV1-COUNT-1: Loop at depth 2 containing:
; LOOP-UNSCALE3-DIV1-NOT: Loop at depth 2 containing:
; LOOP-UNSCALE3-DIV1-COUNT-1: Loop at depth 3 containing:
; LOOP-UNSCALE3-DIV1-NOT: Loop at depth 3 containing:
;
; Half unswitched loop nests, with unscaled3 and div2 it gets more depth1 loops unswitched
; as div2 kicks in.
; LOOP-UNSCALE3-DIV2-COUNT-6: Loop at depth 1 containing:
; LOOP-UNSCALE3-DIV2-NOT: Loop at depth 1 containing:
; LOOP-UNSCALE3-DIV2-COUNT-1: Loop at depth 2 containing:
; LOOP-UNSCALE3-DIV2-NOT: Loop at depth 2 containing:
; LOOP-UNSCALE3-DIV2-COUNT-1: Loop at depth 3 containing:
; LOOP-UNSCALE3-DIV2-NOT: Loop at depth 3 containing:
;
; Maximally unswitched (copy of the outer loop per each condition)
; LOOP-MAX-COUNT-6: Loop at depth 1 containing:
; LOOP-MAX-NOT: Loop at depth 1 containing:
; LOOP-MAX-COUNT-1: Loop at depth 2 containing:
; LOOP-MAX-NOT: Loop at depth 2 containing:
; LOOP-MAX-COUNT-1: Loop at depth 3 containing:
; LOOP-MAX-NOT: Loop at depth 3 containing:
declare void @bar()
define void @loop_nested3_conds5(ptr %addr, i1 %c1, i1 %c2, i1 %c3, i1 %c4, i1 %c5) {
entry:
%addr2 = getelementptr i32, ptr %addr, i64 1
%addr3 = getelementptr i32, ptr %addr, i64 2
br label %outer
outer:
%iv1 = phi i32 [0, %entry], [%iv1.next, %outer_latch]
%iv1.next = add i32 %iv1, 1
;; skip nontrivial unswitch
call void @bar()
br label %middle
middle:
%iv2 = phi i32 [0, %outer], [%iv2.next, %middle_latch]
%iv2.next = add i32 %iv2, 1
;; skip nontrivial unswitch
call void @bar()
br label %loop
loop:
%iv3 = phi i32 [0, %middle], [%iv3.next, %loop_latch]
%iv3.next = add i32 %iv3, 1
;; skip nontrivial unswitch
call void @bar()
br i1 %c1, label %loop_next1_left, label %outer_latch
loop_next1_left:
br label %loop_next1
loop_next1_right:
br label %loop_next1
loop_next1:
br i1 %c2, label %loop_next2_left, label %outer_latch
loop_next2_left:
br label %loop_next2
loop_next2_right:
br label %loop_next2
loop_next2:
br i1 %c3, label %loop_next3_left, label %outer_latch
loop_next3_left:
br label %loop_next3
loop_next3_right:
br label %loop_next3
loop_next3:
br i1 %c4, label %loop_next4_left, label %outer_latch
loop_next4_left:
br label %loop_next4
loop_next4_right:
br label %loop_next4
loop_next4:
br i1 %c5, label %loop_latch_left, label %outer_latch
loop_latch_left:
br label %loop_latch
loop_latch_right:
br label %loop_latch
loop_latch:
store volatile i32 0, ptr %addr
%test_loop = icmp slt i32 %iv3, 50
br i1 %test_loop, label %loop, label %middle_latch
middle_latch:
store volatile i32 0, ptr %addr2
%test_middle = icmp slt i32 %iv2, 50
br i1 %test_middle, label %middle, label %outer_latch
outer_latch:
store volatile i32 0, ptr %addr3
%test_outer = icmp slt i32 %iv1, 50
br i1 %test_outer, label %outer, label %exit
exit:
ret void
}
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