[SLP] Limit GEP lists based on width of index computation.

[fhahn]

Summary

D68667 introduced a tighter limit to the number of GEPs to simplify
together. The limit was based on the vector element size of the pointer,
but the pointers themselves are not actually put in vectors.

IIUC we try to vectorize the index computations here, so we should base
the limit on the vector element size of the computation of the index.

This restores the test regression on AArch64 and also restores the
vectorization for a important pattern in SPEC2006/464.h264ref on
AArch64 (@test_i16_extend). We get a large benefit from doing a single
load up front and then processing the index computations in vectors.

Note that we could probably even further improve the AArch64 codegen, if
we would do zexts to i32 instead of i64 for the sub operands and then do
a single vector sext on the result of the subtractions. AArch64 provides
dedicated vector instructions to do so. Sketch of proof in Alive:
https://alive2.llvm.org/ce/z/A4xYAB

[ABataev]

LG

[spatel]

llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp

7505–7506

We should update this comment with something like the text in this patch description:

// We are trying to vectorize the index computations, so we base
// the vectorization factor on the size of the loaded values rather
// than the size of the GEP itself (the target's pointer size).

?

[fhahn]

Update comment stating why the maximum number of elements is based on the size of the index expression, rather than the GEP as suggested.

[fhahn]

llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp

7505–7506

I've updated the comment as suggested, with slight edits to make it if better with the maximum number of elements below. WDYT? I'll commit it in a bit, unless there are further suggestions.

[spatel]

llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp

7505–7506

That text works for me - thanks!

llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp

for (auto &Entry : GEPs) {
     // If the getelementptr list has fewer than two elements, there's nothing
     // to do.
     if (Entry.second.size() < 2)
       continue;
 
     LLVM_DEBUG(dbgs() << "SLP: Analyzing a getelementptr list of length "
                       << Entry.second.size() << ".\n");
 
     // Process the GEP list in chunks suitable for the target's supported
     // vector size. If a vector register can't hold 1 element, we are done.
     unsigned MaxVecRegSize = R.getMaxVecRegSize();
-    unsigned EltSize = R.getVectorElementSize(Entry.second[0]);
+    unsigned EltSize = R.getVectorElementSize(*Entry.second[0]->idx_begin());
     if (MaxVecRegSize < EltSize)
       continue;
 
     unsigned MaxElts = MaxVecRegSize / EltSize;
     for (unsigned BI = 0, BE = Entry.second.size(); BI < BE; BI += MaxElts) {
       auto Len = std::min<unsigned>(BE - BI, MaxElts);
       auto GEPList = makeArrayRef(&Entry.second[BI], Len);
 

llvm/test/Transforms/SLPVectorizer/AArch64/getelementptr.ll

 ; YAML-NEXT:   - TreeSize:        '5'
 
 ; YAML:      --- !Passed
 ; YAML-NEXT: Pass:            slp-vectorizer
 ; YAML-NEXT: Name:            VectorizedList
 ; YAML-NEXT: Function:        getelementptr_4x32
 ; YAML-NEXT: Args:
 ; YAML-NEXT:   - String:          'SLP vectorized with cost '
-; YAML-NEXT:   - Cost:            '6'
+; YAML-NEXT:   - Cost:            '16'
 ; YAML-NEXT:   - String:          ' and with tree size '
 ; YAML-NEXT:   - TreeSize:        '3'
 
 define i32 @getelementptr_4x32(i32* nocapture readonly %g, i32 %n, i32 %x, i32 %y, i32 %z) {
 ; CHECK-LABEL: @getelementptr_4x32(
 ; CHECK-NEXT:  entry:
 ; CHECK-NEXT:    [[CMP31:%.*]] = icmp sgt i32 [[N:%.*]], 0
 ; CHECK-NEXT:    br i1 [[CMP31]], label [[FOR_BODY_PREHEADER:%.*]], label [[FOR_COND_CLEANUP:%.*]]
 ; CHECK:       for.body.preheader:
-; CHECK-NEXT:    [[TMP0:%.*]] = insertelement <2 x i32> <i32 0, i32 undef>, i32 [[X:%.*]], i32 1
-; CHECK-NEXT:    [[TMP1:%.*]] = insertelement <2 x i32> undef, i32 [[Y:%.*]], i32 0
-; CHECK-NEXT:    [[TMP2:%.*]] = insertelement <2 x i32> [[TMP1]], i32 [[Z:%.*]], i32 1
+; CHECK-NEXT:    [[TMP0:%.*]] = insertelement <4 x i32> <i32 0, i32 undef, i32 undef, i32 undef>, i32 [[X:%.*]], i32 1
+; CHECK-NEXT:    [[TMP1:%.*]] = insertelement <4 x i32> [[TMP0]], i32 [[Y:%.*]], i32 2
+; CHECK-NEXT:    [[TMP2:%.*]] = insertelement <4 x i32> [[TMP1]], i32 [[Z:%.*]], i32 3
 ; CHECK-NEXT:    br label [[FOR_BODY:%.*]]
 ; CHECK:       for.cond.cleanup.loopexit:
-; CHECK-NEXT:    [[TMP3:%.*]] = extractelement <2 x i32> [[TMP22:%.*]], i32 1
+; CHECK-NEXT:    [[TMP3:%.*]] = extractelement <2 x i32> [[TMP21:%.*]], i32 1
 ; CHECK-NEXT:    br label [[FOR_COND_CLEANUP]]
 ; CHECK:       for.cond.cleanup:
 ; CHECK-NEXT:    [[SUM_0_LCSSA:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[TMP3]], [[FOR_COND_CLEANUP_LOOPEXIT:%.*]] ]
 ; CHECK-NEXT:    ret i32 [[SUM_0_LCSSA]]
 ; CHECK:       for.body:
-; CHECK-NEXT:    [[TMP4:%.*]] = phi <2 x i32> [ zeroinitializer, [[FOR_BODY_PREHEADER]] ], [ [[TMP22]], [[FOR_BODY]] ]
+; CHECK-NEXT:    [[TMP4:%.*]] = phi <2 x i32> [ zeroinitializer, [[FOR_BODY_PREHEADER]] ], [ [[TMP21]], [[FOR_BODY]] ]
 ; CHECK-NEXT:    [[TMP5:%.*]] = extractelement <2 x i32> [[TMP4]], i32 0
 ; CHECK-NEXT:    [[T4:%.*]] = shl nsw i32 [[TMP5]], 1
-; CHECK-NEXT:    [[TMP6:%.*]] = insertelement <2 x i32> undef, i32 [[T4]], i32 0
-; CHECK-NEXT:    [[TMP7:%.*]] = shufflevector <2 x i32> [[TMP6]], <2 x i32> undef, <2 x i32> zeroinitializer
-; CHECK-NEXT:    [[TMP8:%.*]] = add nsw <2 x i32> [[TMP7]], [[TMP0]]
-; CHECK-NEXT:    [[TMP9:%.*]] = extractelement <2 x i32> [[TMP8]], i32 0
+; CHECK-NEXT:    [[TMP6:%.*]] = insertelement <4 x i32> undef, i32 [[T4]], i32 0
+; CHECK-NEXT:    [[TMP7:%.*]] = shufflevector <4 x i32> [[TMP6]], <4 x i32> undef, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP8:%.*]] = add nsw <4 x i32> [[TMP7]], [[TMP2]]
+; CHECK-NEXT:    [[TMP9:%.*]] = extractelement <4 x i32> [[TMP8]], i32 0
 ; CHECK-NEXT:    [[TMP10:%.*]] = sext i32 [[TMP9]] to i64
 ; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds i32, i32* [[G:%.*]], i64 [[TMP10]]
 ; CHECK-NEXT:    [[T6:%.*]] = load i32, i32* [[ARRAYIDX]], align 4
 ; CHECK-NEXT:    [[TMP11:%.*]] = extractelement <2 x i32> [[TMP4]], i32 1
 ; CHECK-NEXT:    [[ADD1:%.*]] = add nsw i32 [[T6]], [[TMP11]]
-; CHECK-NEXT:    [[TMP12:%.*]] = extractelement <2 x i32> [[TMP8]], i32 1
+; CHECK-NEXT:    [[TMP12:%.*]] = extractelement <4 x i32> [[TMP8]], i32 1
 ; CHECK-NEXT:    [[TMP13:%.*]] = sext i32 [[TMP12]] to i64
 ; CHECK-NEXT:    [[ARRAYIDX5:%.*]] = getelementptr inbounds i32, i32* [[G]], i64 [[TMP13]]
 ; CHECK-NEXT:    [[T8:%.*]] = load i32, i32* [[ARRAYIDX5]], align 4
 ; CHECK-NEXT:    [[ADD6:%.*]] = add nsw i32 [[ADD1]], [[T8]]
-; CHECK-NEXT:    [[TMP14:%.*]] = add nsw <2 x i32> [[TMP7]], [[TMP2]]
-; CHECK-NEXT:    [[TMP15:%.*]] = extractelement <2 x i32> [[TMP14]], i32 0
-; CHECK-NEXT:    [[TMP16:%.*]] = sext i32 [[TMP15]] to i64
-; CHECK-NEXT:    [[ARRAYIDX10:%.*]] = getelementptr inbounds i32, i32* [[G]], i64 [[TMP16]]
+; CHECK-NEXT:    [[TMP14:%.*]] = extractelement <4 x i32> [[TMP8]], i32 2
+; CHECK-NEXT:    [[TMP15:%.*]] = sext i32 [[TMP14]] to i64
+; CHECK-NEXT:    [[ARRAYIDX10:%.*]] = getelementptr inbounds i32, i32* [[G]], i64 [[TMP15]]
 ; CHECK-NEXT:    [[T10:%.*]] = load i32, i32* [[ARRAYIDX10]], align 4
 ; CHECK-NEXT:    [[ADD11:%.*]] = add nsw i32 [[ADD6]], [[T10]]
-; CHECK-NEXT:    [[TMP17:%.*]] = extractelement <2 x i32> [[TMP14]], i32 1
-; CHECK-NEXT:    [[TMP18:%.*]] = sext i32 [[TMP17]] to i64
-; CHECK-NEXT:    [[ARRAYIDX15:%.*]] = getelementptr inbounds i32, i32* [[G]], i64 [[TMP18]]
+; CHECK-NEXT:    [[TMP16:%.*]] = extractelement <4 x i32> [[TMP8]], i32 3
+; CHECK-NEXT:    [[TMP17:%.*]] = sext i32 [[TMP16]] to i64
+; CHECK-NEXT:    [[ARRAYIDX15:%.*]] = getelementptr inbounds i32, i32* [[G]], i64 [[TMP17]]
 ; CHECK-NEXT:    [[T12:%.*]] = load i32, i32* [[ARRAYIDX15]], align 4
-; CHECK-NEXT:    [[TMP19:%.*]] = insertelement <2 x i32> undef, i32 [[TMP5]], i32 0
-; CHECK-NEXT:    [[TMP20:%.*]] = insertelement <2 x i32> [[TMP19]], i32 [[ADD11]], i32 1
-; CHECK-NEXT:    [[TMP21:%.*]] = insertelement <2 x i32> <i32 1, i32 undef>, i32 [[T12]], i32 1
-; CHECK-NEXT:    [[TMP22]] = add nsw <2 x i32> [[TMP20]], [[TMP21]]
-; CHECK-NEXT:    [[TMP23:%.*]] = extractelement <2 x i32> [[TMP22]], i32 0
-; CHECK-NEXT:    [[EXITCOND:%.*]] = icmp eq i32 [[TMP23]], [[N]]
+; CHECK-NEXT:    [[TMP18:%.*]] = insertelement <2 x i32> undef, i32 [[TMP5]], i32 0
+; CHECK-NEXT:    [[TMP19:%.*]] = insertelement <2 x i32> [[TMP18]], i32 [[ADD11]], i32 1
+; CHECK-NEXT:    [[TMP20:%.*]] = insertelement <2 x i32> <i32 1, i32 undef>, i32 [[T12]], i32 1
+; CHECK-NEXT:    [[TMP21]] = add nsw <2 x i32> [[TMP19]], [[TMP20]]
+; CHECK-NEXT:    [[TMP22:%.*]] = extractelement <2 x i32> [[TMP21]], i32 0
+; CHECK-NEXT:    [[EXITCOND:%.*]] = icmp eq i32 [[TMP22]], [[N]]
 ; CHECK-NEXT:    br i1 [[EXITCOND]], label [[FOR_COND_CLEANUP_LOOPEXIT]], label [[FOR_BODY]]
 ;
 entry:
   %cmp31 = icmp sgt i32 %n, 0
   br i1 %cmp31, label %for.body.preheader, label %for.cond.cleanup
 
 for.body.preheader:
   br label %for.body

 @global = internal global { i32* } zeroinitializer, align 8
 
 ; Make sure we vectorize to maximize the load with when loading i16 and
 ; extending it for compute operations.
 define void @test_i16_extend(i16* %p.1, i16* %p.2, i32 %idx.i32) {
 ; CHECK-LABEL: @test_i16_extend(
 ; CHECK-NEXT:    [[P_0:%.*]] = load i32*, i32** getelementptr inbounds ({ i32* }, { i32* }* @global, i64 0, i32 0), align 8
 ; CHECK-NEXT:    [[IDX_0:%.*]] = zext i32 [[IDX_I32:%.*]] to i64
-; CHECK-NEXT:    [[IDX_2:%.*]] = add nuw nsw i64 [[IDX_0]], 2
-; CHECK-NEXT:    [[IDX_4:%.*]] = add nuw nsw i64 [[IDX_0]], 4
-; CHECK-NEXT:    [[IDX_6:%.*]] = add nuw nsw i64 [[IDX_0]], 6
 ; CHECK-NEXT:    [[TMP53:%.*]] = getelementptr inbounds i16, i16* [[P_1:%.*]], i64 [[IDX_0]]
 ; CHECK-NEXT:    [[TMP56:%.*]] = getelementptr inbounds i16, i16* [[P_2:%.*]], i64 [[IDX_0]]
-; CHECK-NEXT:    [[TMP1:%.*]] = bitcast i16* [[TMP53]] to <2 x i16>*
-; CHECK-NEXT:    [[TMP2:%.*]] = load <2 x i16>, <2 x i16>* [[TMP1]], align 2
-; CHECK-NEXT:    [[TMP3:%.*]] = zext <2 x i16> [[TMP2]] to <2 x i32>
-; CHECK-NEXT:    [[TMP4:%.*]] = bitcast i16* [[TMP56]] to <2 x i16>*
-; CHECK-NEXT:    [[TMP5:%.*]] = load <2 x i16>, <2 x i16>* [[TMP4]], align 2
-; CHECK-NEXT:    [[TMP6:%.*]] = zext <2 x i16> [[TMP5]] to <2 x i32>
-; CHECK-NEXT:    [[TMP7:%.*]] = sub nsw <2 x i32> [[TMP3]], [[TMP6]]
-; CHECK-NEXT:    [[TMP8:%.*]] = extractelement <2 x i32> [[TMP7]], i32 0
+; CHECK-NEXT:    [[TMP1:%.*]] = bitcast i16* [[TMP53]] to <8 x i16>*
+; CHECK-NEXT:    [[TMP2:%.*]] = load <8 x i16>, <8 x i16>* [[TMP1]], align 2
+; CHECK-NEXT:    [[TMP3:%.*]] = zext <8 x i16> [[TMP2]] to <8 x i32>
+; CHECK-NEXT:    [[TMP4:%.*]] = bitcast i16* [[TMP56]] to <8 x i16>*
+; CHECK-NEXT:    [[TMP5:%.*]] = load <8 x i16>, <8 x i16>* [[TMP4]], align 2
+; CHECK-NEXT:    [[TMP6:%.*]] = zext <8 x i16> [[TMP5]] to <8 x i32>
+; CHECK-NEXT:    [[TMP7:%.*]] = sub nsw <8 x i32> [[TMP3]], [[TMP6]]
+; CHECK-NEXT:    [[TMP8:%.*]] = extractelement <8 x i32> [[TMP7]], i32 0
 ; CHECK-NEXT:    [[TMP9:%.*]] = sext i32 [[TMP8]] to i64
 ; CHECK-NEXT:    [[TMP60:%.*]] = getelementptr inbounds i32, i32* [[P_0]], i64 [[TMP9]]
 ; CHECK-NEXT:    [[L_1:%.*]] = load i32, i32* [[TMP60]], align 4
-; CHECK-NEXT:    [[TMP10:%.*]] = extractelement <2 x i32> [[TMP7]], i32 1
+; CHECK-NEXT:    [[TMP10:%.*]] = extractelement <8 x i32> [[TMP7]], i32 1
 ; CHECK-NEXT:    [[TMP11:%.*]] = sext i32 [[TMP10]] to i64
 ; CHECK-NEXT:    [[TMP71:%.*]] = getelementptr inbounds i32, i32* [[P_0]], i64 [[TMP11]]
 ; CHECK-NEXT:    [[L_2:%.*]] = load i32, i32* [[TMP71]], align 4
-; CHECK-NEXT:    [[TMP75:%.*]] = getelementptr inbounds i16, i16* [[P_1]], i64 [[IDX_2]]
-; CHECK-NEXT:    [[TMP78:%.*]] = getelementptr inbounds i16, i16* [[P_2]], i64 [[IDX_2]]
-; CHECK-NEXT:    [[TMP12:%.*]] = bitcast i16* [[TMP75]] to <2 x i16>*
-; CHECK-NEXT:    [[TMP13:%.*]] = load <2 x i16>, <2 x i16>* [[TMP12]], align 2
-; CHECK-NEXT:    [[TMP14:%.*]] = zext <2 x i16> [[TMP13]] to <2 x i32>
-; CHECK-NEXT:    [[TMP15:%.*]] = bitcast i16* [[TMP78]] to <2 x i16>*
-; CHECK-NEXT:    [[TMP16:%.*]] = load <2 x i16>, <2 x i16>* [[TMP15]], align 2
-; CHECK-NEXT:    [[TMP17:%.*]] = zext <2 x i16> [[TMP16]] to <2 x i32>
-; CHECK-NEXT:    [[TMP18:%.*]] = sub nsw <2 x i32> [[TMP14]], [[TMP17]]
-; CHECK-NEXT:    [[TMP19:%.*]] = extractelement <2 x i32> [[TMP18]], i32 0
-; CHECK-NEXT:    [[TMP20:%.*]] = sext i32 [[TMP19]] to i64
-; CHECK-NEXT:    [[TMP82:%.*]] = getelementptr inbounds i32, i32* [[P_0]], i64 [[TMP20]]
+; CHECK-NEXT:    [[TMP12:%.*]] = extractelement <8 x i32> [[TMP7]], i32 2
+; CHECK-NEXT:    [[TMP13:%.*]] = sext i32 [[TMP12]] to i64
+; CHECK-NEXT:    [[TMP82:%.*]] = getelementptr inbounds i32, i32* [[P_0]], i64 [[TMP13]]
 ; CHECK-NEXT:    [[L_3:%.*]] = load i32, i32* [[TMP82]], align 4
-; CHECK-NEXT:    [[TMP21:%.*]] = extractelement <2 x i32> [[TMP18]], i32 1
-; CHECK-NEXT:    [[TMP22:%.*]] = sext i32 [[TMP21]] to i64
-; CHECK-NEXT:    [[TMP93:%.*]] = getelementptr inbounds i32, i32* [[P_0]], i64 [[TMP22]]
+; CHECK-NEXT:    [[TMP14:%.*]] = extractelement <8 x i32> [[TMP7]], i32 3
+; CHECK-NEXT:    [[TMP15:%.*]] = sext i32 [[TMP14]] to i64
+; CHECK-NEXT:    [[TMP93:%.*]] = getelementptr inbounds i32, i32* [[P_0]], i64 [[TMP15]]
 ; CHECK-NEXT:    [[L_4:%.*]] = load i32, i32* [[TMP93]], align 4
-; CHECK-NEXT:    [[TMP97:%.*]] = getelementptr inbounds i16, i16* [[P_1]], i64 [[IDX_4]]
-; CHECK-NEXT:    [[TMP100:%.*]] = getelementptr inbounds i16, i16* [[P_2]], i64 [[IDX_4]]
-; CHECK-NEXT:    [[TMP23:%.*]] = bitcast i16* [[TMP97]] to <2 x i16>*
-; CHECK-NEXT:    [[TMP24:%.*]] = load <2 x i16>, <2 x i16>* [[TMP23]], align 2
-; CHECK-NEXT:    [[TMP25:%.*]] = zext <2 x i16> [[TMP24]] to <2 x i32>
-; CHECK-NEXT:    [[TMP26:%.*]] = bitcast i16* [[TMP100]] to <2 x i16>*
-; CHECK-NEXT:    [[TMP27:%.*]] = load <2 x i16>, <2 x i16>* [[TMP26]], align 2
-; CHECK-NEXT:    [[TMP28:%.*]] = zext <2 x i16> [[TMP27]] to <2 x i32>
-; CHECK-NEXT:    [[TMP29:%.*]] = sub nsw <2 x i32> [[TMP25]], [[TMP28]]
-; CHECK-NEXT:    [[TMP30:%.*]] = extractelement <2 x i32> [[TMP29]], i32 0
-; CHECK-NEXT:    [[TMP31:%.*]] = sext i32 [[TMP30]] to i64
-; CHECK-NEXT:    [[TMP104:%.*]] = getelementptr inbounds i32, i32* [[P_0]], i64 [[TMP31]]
+; CHECK-NEXT:    [[TMP16:%.*]] = extractelement <8 x i32> [[TMP7]], i32 4
+; CHECK-NEXT:    [[TMP17:%.*]] = sext i32 [[TMP16]] to i64
+; CHECK-NEXT:    [[TMP104:%.*]] = getelementptr inbounds i32, i32* [[P_0]], i64 [[TMP17]]
 ; CHECK-NEXT:    [[L_5:%.*]] = load i32, i32* [[TMP104]], align 4
-; CHECK-NEXT:    [[TMP32:%.*]] = extractelement <2 x i32> [[TMP29]], i32 1
-; CHECK-NEXT:    [[TMP33:%.*]] = sext i32 [[TMP32]] to i64
-; CHECK-NEXT:    [[TMP115:%.*]] = getelementptr inbounds i32, i32* [[P_0]], i64 [[TMP33]]
+; CHECK-NEXT:    [[TMP18:%.*]] = extractelement <8 x i32> [[TMP7]], i32 5
+; CHECK-NEXT:    [[TMP19:%.*]] = sext i32 [[TMP18]] to i64
+; CHECK-NEXT:    [[TMP115:%.*]] = getelementptr inbounds i32, i32* [[P_0]], i64 [[TMP19]]
 ; CHECK-NEXT:    [[L_6:%.*]] = load i32, i32* [[TMP115]], align 4
-; CHECK-NEXT:    [[TMP119:%.*]] = getelementptr inbounds i16, i16* [[P_1]], i64 [[IDX_6]]
-; CHECK-NEXT:    [[TMP122:%.*]] = getelementptr inbounds i16, i16* [[P_2]], i64 [[IDX_6]]
-; CHECK-NEXT:    [[TMP34:%.*]] = bitcast i16* [[TMP119]] to <2 x i16>*
-; CHECK-NEXT:    [[TMP35:%.*]] = load <2 x i16>, <2 x i16>* [[TMP34]], align 2
-; CHECK-NEXT:    [[TMP36:%.*]] = zext <2 x i16> [[TMP35]] to <2 x i32>
-; CHECK-NEXT:    [[TMP37:%.*]] = bitcast i16* [[TMP122]] to <2 x i16>*
-; CHECK-NEXT:    [[TMP38:%.*]] = load <2 x i16>, <2 x i16>* [[TMP37]], align 2
-; CHECK-NEXT:    [[TMP39:%.*]] = zext <2 x i16> [[TMP38]] to <2 x i32>
-; CHECK-NEXT:    [[TMP40:%.*]] = sub nsw <2 x i32> [[TMP36]], [[TMP39]]
-; CHECK-NEXT:    [[TMP41:%.*]] = extractelement <2 x i32> [[TMP40]], i32 0
-; CHECK-NEXT:    [[TMP42:%.*]] = sext i32 [[TMP41]] to i64
-; CHECK-NEXT:    [[TMP126:%.*]] = getelementptr inbounds i32, i32* [[P_0]], i64 [[TMP42]]
+; CHECK-NEXT:    [[TMP20:%.*]] = extractelement <8 x i32> [[TMP7]], i32 6
+; CHECK-NEXT:    [[TMP21:%.*]] = sext i32 [[TMP20]] to i64
+; CHECK-NEXT:    [[TMP126:%.*]] = getelementptr inbounds i32, i32* [[P_0]], i64 [[TMP21]]
 ; CHECK-NEXT:    [[L_7:%.*]] = load i32, i32* [[TMP126]], align 4
-; CHECK-NEXT:    [[TMP43:%.*]] = extractelement <2 x i32> [[TMP40]], i32 1
-; CHECK-NEXT:    [[TMP44:%.*]] = sext i32 [[TMP43]] to i64
-; CHECK-NEXT:    [[TMP137:%.*]] = getelementptr inbounds i32, i32* [[P_0]], i64 [[TMP44]]
+; CHECK-NEXT:    [[TMP22:%.*]] = extractelement <8 x i32> [[TMP7]], i32 7
+; CHECK-NEXT:    [[TMP23:%.*]] = sext i32 [[TMP22]] to i64
+; CHECK-NEXT:    [[TMP137:%.*]] = getelementptr inbounds i32, i32* [[P_0]], i64 [[TMP23]]
 ; CHECK-NEXT:    [[L_8:%.*]] = load i32, i32* [[TMP137]], align 4
 ; CHECK-NEXT:    call void @use(i32 [[L_1]], i32 [[L_2]], i32 [[L_3]], i32 [[L_4]], i32 [[L_5]], i32 [[L_6]], i32 [[L_7]], i32 [[L_8]])
 ; CHECK-NEXT:    ret void
 ;
   %g = getelementptr inbounds { i32*}, { i32 *}* @global, i64 0, i32 0
   %p.0 = load i32*, i32** %g, align 8
 
   %idx.0 = zext i32 %idx.i32 to i64