[llvm] 13107cb - [LoopVectorize] Enable more early exit vectorisation tests (#117008)
via llvm-commits
llvm-commits at lists.llvm.org
Wed Dec 18 01:25:49 PST 2024
Author: David Sherwood
Date: 2024-12-18T09:25:45Z
New Revision: 13107cb09441dfeab24fcbcae9f4d3ba4cfc2703
URL: https://github.com/llvm/llvm-project/commit/13107cb09441dfeab24fcbcae9f4d3ba4cfc2703
DIFF: https://github.com/llvm/llvm-project/commit/13107cb09441dfeab24fcbcae9f4d3ba4cfc2703.diff
LOG: [LoopVectorize] Enable more early exit vectorisation tests (#117008)
PR #112138 introduced initial support for dispatching to
multiple exit blocks via split middle blocks. This patch
fixes a few issues so that we can enable more tests to use
the new enable-early-exit-vectorization flag. Fixes are:
1. The code to bail out for any loop live-out values happens
too late. This is because collectUsersInExitBlocks ignores
induction variables, which get dealt with in fixupIVUsers.
I've moved the check much earlier in processLoop by looking
for outside users of loop-defined values.
2. We shouldn't yet be interleaving when vectorising loops
with uncountable early exits, since we've not added support
for this yet.
3. Similarly, we also shouldn't be creating vector epilogues.
4. Similarly, we shouldn't enable tail-folding.
5. The existing implementation doesn't yet support loops
that require scalar epilogues, although I plan to add that
as part of PR #88385.
6. The new split middle blocks weren't being added to the
parent loop.
Added:
llvm/test/Transforms/LoopVectorize/single_early_exit_with_outer_loop.ll
Modified:
llvm/include/llvm/Transforms/Vectorize/LoopVectorize.h
llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
llvm/test/Transforms/LoopVectorize/AArch64/simple_early_exit.ll
llvm/test/Transforms/LoopVectorize/early_exit_legality.ll
llvm/test/Transforms/LoopVectorize/multi_early_exit.ll
llvm/test/Transforms/LoopVectorize/multi_early_exit_live_outs.ll
llvm/test/Transforms/LoopVectorize/single_early_exit_live_outs.ll
Removed:
################################################################################
diff --git a/llvm/include/llvm/Transforms/Vectorize/LoopVectorize.h b/llvm/include/llvm/Transforms/Vectorize/LoopVectorize.h
index 02935d0943f766..b4e5735eb1439e 100644
--- a/llvm/include/llvm/Transforms/Vectorize/LoopVectorize.h
+++ b/llvm/include/llvm/Transforms/Vectorize/LoopVectorize.h
@@ -170,6 +170,15 @@ void reportVectorizationFailure(const StringRef DebugMsg,
const StringRef OREMsg, const StringRef ORETag,
OptimizationRemarkEmitter *ORE, Loop *TheLoop, Instruction *I = nullptr);
+/// Same as above, but the debug message and optimization remark are identical
+inline void reportVectorizationFailure(const StringRef DebugMsg,
+ const StringRef ORETag,
+ OptimizationRemarkEmitter *ORE,
+ Loop *TheLoop,
+ Instruction *I = nullptr) {
+ reportVectorizationFailure(DebugMsg, DebugMsg, ORETag, ORE, TheLoop, I);
+}
+
/// A marker analysis to determine if extra passes should be run after loop
/// vectorization.
struct ShouldRunExtraVectorPasses
diff --git a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
index 749336939b7109..a6acc710a34c89 100644
--- a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
+++ b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -3039,6 +3039,22 @@ void InnerLoopVectorizer::fixVectorizedLoop(VPTransformState &State) {
PSE.getSE()->forgetLoop(OrigLoop);
PSE.getSE()->forgetBlockAndLoopDispositions();
+ // When dealing with uncountable early exits we create middle.split blocks
+ // between the vector loop region and the exit block. These blocks need
+ // adding to any outer loop.
+ VPRegionBlock *VectorRegion = State.Plan->getVectorLoopRegion();
+ Loop *OuterLoop = OrigLoop->getParentLoop();
+ if (Legal->hasUncountableEarlyExit() && OuterLoop) {
+ VPBasicBlock *MiddleVPBB = State.Plan->getMiddleBlock();
+ VPBlockBase *PredVPBB = MiddleVPBB->getSinglePredecessor();
+ while (PredVPBB && PredVPBB != VectorRegion) {
+ BasicBlock *MiddleSplitBB =
+ State.CFG.VPBB2IRBB[cast<VPBasicBlock>(PredVPBB)];
+ OuterLoop->addBasicBlockToLoop(MiddleSplitBB, *LI);
+ PredVPBB = PredVPBB->getSinglePredecessor();
+ }
+ }
+
// After vectorization, the exit blocks of the original loop will have
// additional predecessors. Invalidate SCEVs for the exit phis in case SE
// looked through single-entry phis.
@@ -3069,7 +3085,6 @@ void InnerLoopVectorizer::fixVectorizedLoop(VPTransformState &State) {
for (Instruction *PI : PredicatedInstructions)
sinkScalarOperands(&*PI);
- VPRegionBlock *VectorRegion = State.Plan->getVectorLoopRegion();
VPBasicBlock *HeaderVPBB = VectorRegion->getEntryBasicBlock();
BasicBlock *HeaderBB = State.CFG.VPBB2IRBB[HeaderVPBB];
@@ -4776,6 +4791,7 @@ bool LoopVectorizationPlanner::isCandidateForEpilogueVectorization(
// Epilogue vectorization code has not been auditted to ensure it handles
// non-latch exits properly. It may be fine, but it needs auditted and
// tested.
+ // TODO: Add support for loops with an early exit.
if (OrigLoop->getExitingBlock() != OrigLoop->getLoopLatch())
return false;
@@ -5024,6 +5040,12 @@ LoopVectorizationCostModel::selectInterleaveCount(ElementCount VF,
if (!Legal->isSafeForAnyVectorWidth())
return 1;
+ // We don't attempt to perform interleaving for loops with uncountable early
+ // exits because the VPInstruction::AnyOf code cannot currently handle
+ // multiple parts.
+ if (Legal->hasUncountableEarlyExit())
+ return 1;
+
auto BestKnownTC = getSmallBestKnownTC(PSE, TheLoop);
const bool HasReductions = !Legal->getReductionVars().empty();
@@ -7837,6 +7859,8 @@ DenseMap<const SCEV *, Value *> LoopVectorizationPlanner::executePlan(
// 2.5 When vectorizing the epilogue, fix reduction and induction resume
// values from the additional bypass block.
if (VectorizingEpilogue) {
+ assert(!ILV.Legal->hasUncountableEarlyExit() &&
+ "Epilogue vectorisation not yet supported with early exits");
BasicBlock *BypassBlock = ILV.getAdditionalBypassBlock();
for (VPRecipeBase &R : *ExitVPBB) {
fixReductionScalarResumeWhenVectorizingEpilog(
@@ -10202,13 +10226,36 @@ bool LoopVectorizePass::processLoop(Loop *L) {
return false;
}
- if (LVL.hasUncountableEarlyExit() && !EnableEarlyExitVectorization) {
- reportVectorizationFailure("Auto-vectorization of loops with uncountable "
- "early exit is not enabled",
- "Auto-vectorization of loops with uncountable "
- "early exit is not enabled",
- "UncountableEarlyExitLoopsDisabled", ORE, L);
- return false;
+ if (LVL.hasUncountableEarlyExit()) {
+ if (!EnableEarlyExitVectorization) {
+ reportVectorizationFailure("Auto-vectorization of loops with uncountable "
+ "early exit is not enabled",
+ "UncountableEarlyExitLoopsDisabled", ORE, L);
+ return false;
+ }
+
+ // In addUsersInExitBlocks we already bail out if there is an outside use
+ // of a loop-defined variable, but it ignores induction variables which are
+ // handled by InnerLoopVectorizer::fixupIVUsers. We need to bail out if we
+ // encounter induction variables too otherwise fixupIVUsers will crash.
+ BasicBlock *LoopLatch = L->getLoopLatch();
+ for (const auto &Induction : LVL.getInductionVars()) {
+ PHINode *Ind = Induction.first;
+ Instruction *IndUpdate =
+ cast<Instruction>(Ind->getIncomingValueForBlock(LoopLatch));
+ for (Instruction *I : {cast<Instruction>(Ind), IndUpdate}) {
+ for (User *U : I->users()) {
+ Instruction *UI = cast<Instruction>(U);
+ if (!L->contains(UI)) {
+ reportVectorizationFailure(
+ "Auto-vectorization of loops with uncountable early exits and "
+ "outside uses of induction variables unsupported",
+ "UncountableEarlyExitLoopIndLiveOutsUnsupported", ORE, L);
+ return false;
+ }
+ }
+ }
+ }
}
// Entrance to the VPlan-native vectorization path. Outer loops are processed
@@ -10233,6 +10280,18 @@ bool LoopVectorizePass::processLoop(Loop *L) {
if (UseInterleaved)
IAI.analyzeInterleaving(useMaskedInterleavedAccesses(*TTI));
+ if (LVL.hasUncountableEarlyExit()) {
+ BasicBlock *LoopLatch = L->getLoopLatch();
+ if (IAI.requiresScalarEpilogue() ||
+ any_of(LVL.getCountableExitingBlocks(),
+ [LoopLatch](BasicBlock *BB) { return BB != LoopLatch; })) {
+ reportVectorizationFailure("Auto-vectorization of early exit loops "
+ "requiring a scalar epilogue is unsupported",
+ "UncountableEarlyExitUnsupported", ORE, L);
+ return false;
+ }
+ }
+
// Check the function attributes and profiles to find out if this function
// should be optimized for size.
ScalarEpilogueLowering SEL =
diff --git a/llvm/test/Transforms/LoopVectorize/AArch64/simple_early_exit.ll b/llvm/test/Transforms/LoopVectorize/AArch64/simple_early_exit.ll
index 82556bdd2a5ec1..18fb96dddb87aa 100644
--- a/llvm/test/Transforms/LoopVectorize/AArch64/simple_early_exit.ll
+++ b/llvm/test/Transforms/LoopVectorize/AArch64/simple_early_exit.ll
@@ -1,5 +1,5 @@
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 4
-; RUN: opt -S < %s -p loop-vectorize | FileCheck %s --check-prefixes=CHECK
+; RUN: opt -S < %s -p loop-vectorize -enable-early-exit-vectorization | FileCheck %s --check-prefixes=CHECK
target triple = "aarch64-unknown-linux-gnu"
@@ -272,22 +272,66 @@ define i32 @
diff _exit_block_needs_scev_check(i32 %end) {
; CHECK-NEXT: call void @init_mem(ptr [[P1]], i64 1024)
; CHECK-NEXT: call void @init_mem(ptr [[P2]], i64 1024)
; CHECK-NEXT: [[END_CLAMPED:%.*]] = and i32 [[END]], 1023
+; CHECK-NEXT: [[TMP19:%.*]] = trunc i32 [[END]] to i10
+; CHECK-NEXT: [[TMP20:%.*]] = zext i10 [[TMP19]] to i64
+; CHECK-NEXT: [[UMAX1:%.*]] = call i64 @llvm.umax.i64(i64 [[TMP20]], i64 1)
+; CHECK-NEXT: [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[UMAX1]], 12
+; CHECK-NEXT: br i1 [[MIN_ITERS_CHECK]], label [[SCALAR_PH:%.*]], label [[VECTOR_SCEVCHECK:%.*]]
+; CHECK: vector.scevcheck:
+; CHECK-NEXT: [[UMAX:%.*]] = call i32 @llvm.umax.i32(i32 [[END_CLAMPED]], i32 1)
+; CHECK-NEXT: [[TMP2:%.*]] = add nsw i32 [[UMAX]], -1
+; CHECK-NEXT: [[TMP3:%.*]] = trunc i32 [[TMP2]] to i8
+; CHECK-NEXT: [[TMP4:%.*]] = add i8 1, [[TMP3]]
+; CHECK-NEXT: [[TMP5:%.*]] = icmp ult i8 [[TMP4]], 1
+; CHECK-NEXT: [[TMP6:%.*]] = icmp ugt i32 [[TMP2]], 255
+; CHECK-NEXT: [[TMP7:%.*]] = or i1 [[TMP5]], [[TMP6]]
+; CHECK-NEXT: br i1 [[TMP7]], label [[SCALAR_PH]], label [[VECTOR_PH:%.*]]
+; CHECK: vector.ph:
+; CHECK-NEXT: [[N_MOD_VF:%.*]] = urem i64 [[UMAX1]], 4
+; CHECK-NEXT: [[N_VEC:%.*]] = sub i64 [[UMAX1]], [[N_MOD_VF]]
+; CHECK-NEXT: [[IND_END:%.*]] = trunc i64 [[N_VEC]] to i8
; CHECK-NEXT: br label [[FOR_BODY1:%.*]]
+; CHECK: vector.body:
+; CHECK-NEXT: [[INDEX:%.*]] = phi i64 [ 0, [[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], [[FOR_BODY1]] ]
+; CHECK-NEXT: [[TMP8:%.*]] = add i64 [[INDEX]], 0
+; CHECK-NEXT: [[TMP9:%.*]] = getelementptr inbounds i32, ptr [[P1]], i64 [[TMP8]]
+; CHECK-NEXT: [[TMP10:%.*]] = getelementptr inbounds i32, ptr [[TMP9]], i32 0
+; CHECK-NEXT: [[WIDE_LOAD:%.*]] = load <4 x i32>, ptr [[TMP10]], align 4
+; CHECK-NEXT: [[TMP11:%.*]] = getelementptr inbounds i32, ptr [[P2]], i64 [[TMP8]]
+; CHECK-NEXT: [[TMP12:%.*]] = getelementptr inbounds i32, ptr [[TMP11]], i32 0
+; CHECK-NEXT: [[WIDE_LOAD3:%.*]] = load <4 x i32>, ptr [[TMP12]], align 4
+; CHECK-NEXT: [[TMP13:%.*]] = icmp eq <4 x i32> [[WIDE_LOAD]], [[WIDE_LOAD3]]
+; CHECK-NEXT: [[TMP14:%.*]] = xor <4 x i1> [[TMP13]], splat (i1 true)
+; CHECK-NEXT: [[INDEX_NEXT]] = add nuw i64 [[INDEX]], 4
+; CHECK-NEXT: [[TMP15:%.*]] = xor <4 x i1> [[TMP14]], splat (i1 true)
+; CHECK-NEXT: [[TMP16:%.*]] = call i1 @llvm.vector.reduce.or.v4i1(<4 x i1> [[TMP15]])
+; CHECK-NEXT: [[TMP17:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT: [[TMP18:%.*]] = or i1 [[TMP16]], [[TMP17]]
+; CHECK-NEXT: br i1 [[TMP18]], label [[MIDDLE_SPLIT:%.*]], label [[FOR_BODY1]], !llvm.loop [[LOOP0:![0-9]+]]
+; CHECK: middle.split:
+; CHECK-NEXT: br i1 [[TMP16]], label [[FOUND:%.*]], label [[MIDDLE_BLOCK:%.*]]
+; CHECK: middle.block:
+; CHECK-NEXT: [[CMP_N:%.*]] = icmp eq i64 [[UMAX1]], [[N_VEC]]
+; CHECK-NEXT: br i1 [[CMP_N]], label [[EXIT:%.*]], label [[SCALAR_PH]]
+; CHECK: scalar.ph:
+; CHECK-NEXT: [[BC_RESUME_VAL:%.*]] = phi i8 [ [[IND_END]], [[MIDDLE_BLOCK]] ], [ 0, [[ENTRY:%.*]] ], [ 0, [[VECTOR_SCEVCHECK]] ]
+; CHECK-NEXT: [[BC_RESUME_VAL2:%.*]] = phi i64 [ [[N_VEC]], [[MIDDLE_BLOCK]] ], [ 0, [[ENTRY]] ], [ 0, [[VECTOR_SCEVCHECK]] ]
+; CHECK-NEXT: br label [[FOR_BODY:%.*]]
; CHECK: for.body:
-; CHECK-NEXT: [[IND:%.*]] = phi i8 [ [[IND_NEXT:%.*]], [[FOR_INC:%.*]] ], [ 0, [[ENTRY:%.*]] ]
-; CHECK-NEXT: [[GEP_IND:%.*]] = phi i64 [ [[GEP_IND_NEXT:%.*]], [[FOR_INC]] ], [ 0, [[ENTRY]] ]
+; CHECK-NEXT: [[IND:%.*]] = phi i8 [ [[IND_NEXT:%.*]], [[FOR_INC:%.*]] ], [ [[BC_RESUME_VAL]], [[SCALAR_PH]] ]
+; CHECK-NEXT: [[GEP_IND:%.*]] = phi i64 [ [[GEP_IND_NEXT:%.*]], [[FOR_INC]] ], [ [[BC_RESUME_VAL2]], [[SCALAR_PH]] ]
; CHECK-NEXT: [[ARRAYIDX1:%.*]] = getelementptr inbounds i32, ptr [[P1]], i64 [[GEP_IND]]
; CHECK-NEXT: [[TMP0:%.*]] = load i32, ptr [[ARRAYIDX1]], align 4
; CHECK-NEXT: [[ARRAYIDX2:%.*]] = getelementptr inbounds i32, ptr [[P2]], i64 [[GEP_IND]]
; CHECK-NEXT: [[TMP1:%.*]] = load i32, ptr [[ARRAYIDX2]], align 4
; CHECK-NEXT: [[CMP_EARLY:%.*]] = icmp eq i32 [[TMP0]], [[TMP1]]
-; CHECK-NEXT: br i1 [[CMP_EARLY]], label [[FOUND:%.*]], label [[FOR_INC]]
+; CHECK-NEXT: br i1 [[CMP_EARLY]], label [[FOUND]], label [[FOR_INC]]
; CHECK: for.inc:
; CHECK-NEXT: [[IND_NEXT]] = add i8 [[IND]], 1
; CHECK-NEXT: [[CONV:%.*]] = zext i8 [[IND_NEXT]] to i32
; CHECK-NEXT: [[GEP_IND_NEXT]] = add i64 [[GEP_IND]], 1
; CHECK-NEXT: [[CMP:%.*]] = icmp ult i32 [[CONV]], [[END_CLAMPED]]
-; CHECK-NEXT: br i1 [[CMP]], label [[FOR_BODY1]], label [[EXIT:%.*]]
+; CHECK-NEXT: br i1 [[CMP]], label [[FOR_BODY]], label [[EXIT]], !llvm.loop [[LOOP3:![0-9]+]]
; CHECK: found:
; CHECK-NEXT: ret i32 1
; CHECK: exit:
@@ -325,9 +369,58 @@ exit:
ret i32 0
}
+%my.struct = type { i8, i8 }
+
+define i64 @same_exit_block_requires_interleaving() {
+; CHECK-LABEL: define i64 @same_exit_block_requires_interleaving() {
+; CHECK-NEXT: entry:
+; CHECK-NEXT: [[P1:%.*]] = alloca [128 x %my.struct], align 8
+; CHECK-NEXT: call void @init_mem(ptr [[P1]], i64 256)
+; CHECK-NEXT: br label [[LOOP:%.*]]
+; CHECK: loop:
+; CHECK-NEXT: [[INDEX:%.*]] = phi i64 [ [[INDEX_NEXT:%.*]], [[LOOP_LATCH:%.*]] ], [ 3, [[ENTRY:%.*]] ]
+; CHECK-NEXT: [[ARRAYIDX:%.*]] = getelementptr inbounds [128 x %my.struct], ptr [[P1]], i64 0, i64 [[INDEX]]
+; CHECK-NEXT: [[LD1:%.*]] = load i8, ptr [[ARRAYIDX]], align 1
+; CHECK-NEXT: [[CMP3:%.*]] = icmp eq i8 [[LD1]], 3
+; CHECK-NEXT: br i1 [[CMP3]], label [[LOOP_LATCH]], label [[LOOP_END:%.*]]
+; CHECK: loop.latch:
+; CHECK-NEXT: [[INDEX_NEXT]] = add i64 [[INDEX]], 1
+; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i64 [[INDEX_NEXT]], 69
+; CHECK-NEXT: br i1 [[EXITCOND]], label [[LOOP]], label [[LOOP_END]]
+; CHECK: loop.end:
+; CHECK-NEXT: [[RETVAL:%.*]] = phi i64 [ 0, [[LOOP_LATCH]] ], [ 1, [[LOOP]] ]
+; CHECK-NEXT: ret i64 [[RETVAL]]
+;
+entry:
+ %p1 = alloca [128 x %my.struct]
+ call void @init_mem(ptr %p1, i64 256)
+ br label %loop
+
+loop:
+ %index = phi i64 [ %index.next, %loop.latch ], [ 3, %entry ]
+ %arrayidx = getelementptr inbounds [128 x %my.struct], ptr %p1, i64 0, i64 %index
+ %ld1 = load i8, ptr %arrayidx, align 1
+ %cmp3 = icmp eq i8 %ld1, 3
+ br i1 %cmp3, label %loop.latch, label %loop.end
+
+loop.latch:
+ %index.next = add i64 %index, 1
+ %exitcond = icmp ne i64 %index.next, 69
+ br i1 %exitcond, label %loop, label %loop.end
+
+loop.end:
+ %retval = phi i64 [ 0, %loop.latch ], [ 1, %loop ]
+ ret i64 %retval
+}
declare i32 @foo(i32) readonly
declare <vscale x 4 x i32> @foo_vec(<vscale x 4 x i32>)
attributes #0 = { "vector-function-abi-variant"="_ZGVsNxv_foo(foo_vec)" }
attributes #1 = { "target-features"="+sve" vscale_range(1,16) }
+;.
+; CHECK: [[LOOP0]] = distinct !{[[LOOP0]], [[META1:![0-9]+]], [[META2:![0-9]+]]}
+; CHECK: [[META1]] = !{!"llvm.loop.isvectorized", i32 1}
+; CHECK: [[META2]] = !{!"llvm.loop.unroll.runtime.disable"}
+; CHECK: [[LOOP3]] = distinct !{[[LOOP3]], [[META1]]}
+;.
diff --git a/llvm/test/Transforms/LoopVectorize/early_exit_legality.ll b/llvm/test/Transforms/LoopVectorize/early_exit_legality.ll
index 2a99693523d3cf..ac78c40ec92c6c 100644
--- a/llvm/test/Transforms/LoopVectorize/early_exit_legality.ll
+++ b/llvm/test/Transforms/LoopVectorize/early_exit_legality.ll
@@ -49,7 +49,7 @@ define i64 @same_exit_block_pre_inc_use1() {
; CHECK-LABEL: LV: Checking a loop in 'same_exit_block_pre_inc_use1'
; CHECK: LV: Found an early exit loop with symbolic max backedge taken count: 63
; CHECK-NEXT: LV: We can vectorize this loop!
-; CHECK-NOT: LV: Not vectorizing
+; CHECK-NEXT: LV: Not vectorizing: Auto-vectorization of loops with uncountable early exits and outside uses of induction variables unsupported
entry:
%p1 = alloca [1024 x i8]
%p2 = alloca [1024 x i8]
@@ -141,7 +141,7 @@ define i64 @loop_contains_load_after_early_exit(ptr dereferenceable(1024) align(
; CHECK-LABEL: LV: Checking a loop in 'loop_contains_load_after_early_exit'
; CHECK: LV: Found an early exit loop with symbolic max backedge taken count: 63
; CHECK-NEXT: LV: We can vectorize this loop!
-; CHECK: LV: Not vectorizing: Some exit values in loop with uncountable exit not supported yet.
+; CHECK: LV: Not vectorizing: Auto-vectorization of loops with uncountable early exits and outside uses of induction variables unsupported
entry:
%p1 = alloca [1024 x i8]
call void @init_mem(ptr %p1, i64 1024)
@@ -167,6 +167,42 @@ loop.end:
}
+define i64 @one_uncountable_two_countable_same_exit_phi_of_consts() {
+; CHECK-LABEL: LV: Checking a loop in 'one_uncountable_two_countable_same_exit_phi_of_consts'
+; CHECK: LV: Found an early exit loop with symbolic max backedge taken count: 61
+; CHECK-NEXT: LV: We can vectorize this loop!
+; CHECK-NEXT: LV: Not vectorizing: Auto-vectorization of early exit loops requiring a scalar epilogue is unsupported.
+entry:
+ %p1 = alloca [1024 x i8]
+ %p2 = alloca [1024 x i8]
+ call void @init_mem(ptr %p1, i64 1024)
+ call void @init_mem(ptr %p2, i64 1024)
+ br label %loop
+
+loop:
+ %index = phi i64 [ %index.next, %loop.inc ], [ 3, %entry ]
+ %cmp1 = icmp ne i64 %index, 64
+ br i1 %cmp1, label %search, label %loop.end
+
+search:
+ %arrayidx = getelementptr inbounds i8, ptr %p1, i64 %index
+ %ld1 = load i8, ptr %arrayidx, align 1
+ %arrayidx1 = getelementptr inbounds i8, ptr %p2, i64 %index
+ %ld2 = load i8, ptr %arrayidx1, align 1
+ %cmp3 = icmp eq i8 %ld1, %ld2
+ br i1 %cmp3, label %loop.end, label %loop.inc
+
+loop.inc:
+ %index.next = add i64 %index, 1
+ %exitcond = icmp ne i64 %index.next, 128
+ br i1 %exitcond, label %loop, label %loop.end
+
+loop.end:
+ %retval = phi i64 [ 0, %loop ], [ 1, %search ], [ 0, %loop.inc ]
+ ret i64 %retval
+}
+
+
; == SOME ILLEGAL EXAMPLES ==
diff --git a/llvm/test/Transforms/LoopVectorize/multi_early_exit.ll b/llvm/test/Transforms/LoopVectorize/multi_early_exit.ll
index 94af5b7c7607da..0e753a535cd2d3 100644
--- a/llvm/test/Transforms/LoopVectorize/multi_early_exit.ll
+++ b/llvm/test/Transforms/LoopVectorize/multi_early_exit.ll
@@ -1,5 +1,5 @@
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 4
-; RUN: opt -S < %s -p loop-vectorize | FileCheck %s
+; RUN: opt -S < %s -p loop-vectorize -enable-early-exit-vectorization | FileCheck %s
declare void @init_mem(ptr, i64);
diff --git a/llvm/test/Transforms/LoopVectorize/multi_early_exit_live_outs.ll b/llvm/test/Transforms/LoopVectorize/multi_early_exit_live_outs.ll
index 7759c10032e9bd..4027f6a0f5dfdc 100644
--- a/llvm/test/Transforms/LoopVectorize/multi_early_exit_live_outs.ll
+++ b/llvm/test/Transforms/LoopVectorize/multi_early_exit_live_outs.ll
@@ -1,5 +1,5 @@
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 4
-; RUN: opt -S < %s -p loop-vectorize | FileCheck %s
+; RUN: opt -S < %s -p loop-vectorize -enable-early-exit-vectorization | FileCheck %s
declare void @init_mem(ptr, i64);
diff --git a/llvm/test/Transforms/LoopVectorize/single_early_exit_live_outs.ll b/llvm/test/Transforms/LoopVectorize/single_early_exit_live_outs.ll
index 7889191c4b5bae..7f00e77b9169dd 100644
--- a/llvm/test/Transforms/LoopVectorize/single_early_exit_live_outs.ll
+++ b/llvm/test/Transforms/LoopVectorize/single_early_exit_live_outs.ll
@@ -1,5 +1,5 @@
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 4
-; RUN: opt -S < %s -p loop-vectorize | FileCheck %s
+; RUN: opt -S < %s -p loop-vectorize -enable-early-exit-vectorization | FileCheck %s
declare void @init_mem(ptr, i64);
diff --git a/llvm/test/Transforms/LoopVectorize/single_early_exit_with_outer_loop.ll b/llvm/test/Transforms/LoopVectorize/single_early_exit_with_outer_loop.ll
new file mode 100644
index 00000000000000..fefed2d859767f
--- /dev/null
+++ b/llvm/test/Transforms/LoopVectorize/single_early_exit_with_outer_loop.ll
@@ -0,0 +1,91 @@
+; RUN: opt -S < %s -p loop-vectorize,'print<loops>' -disable-output -enable-early-exit-vectorization 2>&1 | FileCheck %s
+
+declare void @init_mem(ptr, i64);
+
+; Tests that the additional middle.split created for handling loops with
+; uncountable early exits is correctly adding to the outer loop at depth 1.
+define void @early_exit_in_outer_loop1() {
+; CHECK-LABEL: Loop info for function 'early_exit_in_outer_loop1':
+; CHECK: Loop at depth 1 containing: {{.*}}%middle.block,%scalar.ph,%vector.ph,%vector.body,%middle.split
+entry:
+ %p1 = alloca [1024 x i8]
+ %p2 = alloca [1024 x i8]
+ call void @init_mem(ptr %p1, i64 1024)
+ call void @init_mem(ptr %p2, i64 1024)
+ br label %loop.outer
+
+loop.outer:
+ %count = phi i64 [ 0, %entry ], [ %count.next, %loop.inner.end ]
+ br label %loop.inner
+
+loop.inner:
+ %index = phi i64 [ %index.next, %loop.inner.inc ], [ 3, %loop.outer ]
+ %arrayidx = getelementptr inbounds i8, ptr %p1, i64 %index
+ %ld1 = load i8, ptr %arrayidx, align 1
+ %arrayidx1 = getelementptr inbounds i8, ptr %p2, i64 %index
+ %ld2 = load i8, ptr %arrayidx1, align 1
+ %cmp3 = icmp eq i8 %ld1, %ld2
+ br i1 %cmp3, label %loop.inner.inc, label %loop.inner.found
+
+loop.inner.inc:
+ %index.next = add i64 %index, 1
+ %exitcond = icmp ne i64 %index.next, 67
+ br i1 %exitcond, label %loop.inner, label %loop.inner.end
+
+loop.inner.found:
+ br label %loop.inner.end
+
+loop.inner.end:
+ %count.next = phi i64 [ 0, %loop.inner.inc ], [ 1, %loop.inner.found ]
+ br label %loop.outer
+}
+
+; Tests that the additional middle.split created for handling loops with
+; uncountable early exits is correctly adding to both the outer and middle
+; loops at depths 1 and 2, respectively.
+define void @early_exit_in_outer_loop2() {
+; CHECK-LABEL: Loop info for function 'early_exit_in_outer_loop2':
+; CHECK: Loop at depth 1 containing: {{.*}}%middle.block,%scalar.ph,%vector.ph,%vector.body,%middle.split
+; CHECK: Loop at depth 2 containing: {{.*}}%middle.block,%scalar.ph,%vector.ph,%vector.body,%middle.split<exiting>
+entry:
+ %p1 = alloca [1024 x i8]
+ %p2 = alloca [1024 x i8]
+ call void @init_mem(ptr %p1, i64 1024)
+ call void @init_mem(ptr %p2, i64 1024)
+ br label %loop.outer
+
+loop.outer:
+ %count.outer = phi i64 [ 0, %entry ], [ %count.outer.next , %loop.outer.latch ]
+ br label %loop.middle
+
+loop.middle:
+ br label %loop.inner
+
+loop.inner:
+ %index = phi i64 [ %index.next, %loop.inner.inc ], [ 3, %loop.middle ]
+ %arrayidx = getelementptr inbounds i8, ptr %p1, i64 %index
+ %ld1 = load i8, ptr %arrayidx, align 1
+ %arrayidx1 = getelementptr inbounds i8, ptr %p2, i64 %index
+ %ld2 = load i8, ptr %arrayidx1, align 1
+ %cmp3 = icmp eq i8 %ld1, %ld2
+ br i1 %cmp3, label %loop.inner.inc, label %loop.inner.found
+
+loop.inner.inc:
+ %index.next = add i64 %index, 1
+ %exitcond = icmp ne i64 %index.next, 67
+ br i1 %exitcond, label %loop.inner, label %loop.inner.end
+
+loop.inner.end:
+ br i1 false, label %loop.middle, label %loop.middle.end
+
+loop.middle.end:
+ br label %loop.outer.latch
+
+loop.inner.found:
+ br label %loop.outer.latch
+
+loop.outer.latch:
+ %t = phi i64 [ 0, %loop.middle.end ], [ 1, %loop.inner.found ]
+ %count.outer.next = add i64 %count.outer, %t
+ br label %loop.outer
+}
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