[ARM][ARMLoadStoreOptimizer]

[LukeCheeseman]

Summary

• The load store optimizer is currently merging multiple loads/stores into VLDM/VSTM with more than 16 doubleword registers
• This is an UNPREDICTABLE instruction and shouldn't be done
• It looks like the Limit for how many registers included in a merge got dropped at some point so I am reintroducing it in this patch
• This fixes https://bugs.llvm.org/show_bug.cgi?id=38389

[efriedma]

How hard would it be to generate two vstmia instructions? I think you can just move the limit check into the "Merge following instructions where possible" loop. The generated code is more efficient, and it's easier to verify the testcase doesn't break for some other reason.

lib/Target/ARM/ARMLoadStoreOptimizer.cpp

1094

This limit isn't actually useful...? There are only 32 float registers anyway.

1859

How is this change related?

[LukeCheeseman]

• Remove extra limit cases that were unnecessary
• Check the Count/Limit on each iteration of the merge loop
• Replace guard with assert, previously only candidates that couldn't be merge were one instruction long

[efriedma]

lib/Target/ARM/ARMLoadStoreOptimizer.cpp

1054

Instead of disabling merging, could we just do something like "if (Count == Limit) break;", so we merge the first 16 stores, then consider any remaining stores as a separate set?

[MatzeB]

Please create a .mir test that just checks the ARMLoadStoreOptimizer pass. See test/CodeGen/ARM/vldm-liveness.mir or test/CodeGen/ARM/load_store_opt_kill.mir for example.

[LukeCheeseman]

lib/Target/ARM/ARMLoadStoreOptimizer.cpp

1054

Ah yes, that's a much better idea. Thanks

[LukeCheeseman]

• Break out of the merge loop so that 16 doubleword register loads get merged and the next registers get inspected independently
• Add a MIR test that checks only the arm load store optimizer pass

[LukeCheeseman]

• Removing some extraneous MIR input

[efriedma]

MIR can be simplified more; see http://llvm.org/docs/MIRLangRef.html#simplifying-mir-files .

[LukeCheeseman]

• Reduce MIR test, remove lots of unnecessary info

[MatzeB]

The new .mir test is nicely concise now. Maybe we can even do without the .ll test now?

LGTM with nitpicks addressed and when Eli agrees.

test/CodeGen/ARM/load_store_opt_reg_limit.mir

2–10

You should be able to drop the whole IR block too I think.

12

Better style: # CHECK-LABEL: name: _Z2brR1lI1ME (may also consider choosing a simpler function name)

[LukeCheeseman]

• Remove .ll test and simplify mir test

[efriedma]

LGTM

[LukeCheeseman]

Closed by r342872

lib/Target/ARM/ARMLoadStoreOptimizer.cpp

do {
     // deprecated; LDM to PC is fine but cannot happen here.
     if (PReg == ARM::SP || PReg == ARM::PC)
       CanMergeToLSMulti = CanMergeToLSDouble = false;
 
     // Should we be conservative?
     if (AssumeMisalignedLoadStores && !mayCombineMisaligned(*STI, *MI))
       CanMergeToLSMulti = CanMergeToLSDouble = false;
 
+    // vldm / vstm limit are 32 for S variants, 16 for D variants.
+    unsigned Limit;
+    switch (Opcode) {
+    default:
+      Limit = UINT_MAX;
+      break;
+    case ARM::VLDRD:
+    case ARM::VSTRD:
+      Limit = 16;
+      break;
+    }
+
     // Merge following instructions where possible.
     for (unsigned I = SIndex+1; I < EIndex; ++I, ++Count) {
       int NewOffset = MemOps[I].Offset;
       if (NewOffset != Offset + (int)Size)
         break;
       const MachineOperand &MO = getLoadStoreRegOp(*MemOps[I].MI);
       unsigned Reg = MO.getReg();
       if (Reg == ARM::SP || Reg == ARM::PC)
         break;
+      if (Count == Limit)
+        break;
 
       // See if the current load/store may be part of a multi load/store.
       unsigned RegNum = MO.isUndef() ? std::numeric_limits<unsigned>::max()
                                      : TRI->getEncodingValue(Reg);
       bool PartOfLSMulti = CanMergeToLSMulti;
       if (PartOfLSMulti) {
         // Register numbers must be in ascending order.
         if (RegNum <= PRegNum)
           PartOfLSMulti = false;
         // For VFP / NEON load/store multiples, the registers must be
do {
 
     // Form a candidate from the Ops collected so far.
     MergeCandidate *Candidate = new(Allocator.Allocate()) MergeCandidate;
     for (unsigned C = SIndex, CE = SIndex + Count; C < CE; ++C)
       Candidate->Instrs.push_back(MemOps[C].MI);
     Candidate->LatestMIIdx = Latest - SIndex;
     Candidate->EarliestMIIdx = Earliest - SIndex;
     Candidate->InsertPos = MemOps[Latest].Position;
     if (Count == 1)
       CanMergeToLSMulti = CanMergeToLSDouble = false;
     Candidate->CanMergeToLSMulti = CanMergeToLSMulti;
     Candidate->CanMergeToLSDouble = CanMergeToLSDouble;
     Candidates.push_back(Candidate);
     // Continue after the chain.
     SIndex += Count;
   } while (SIndex < EIndex);
 }
if (Candidate->CanMergeToLSMulti || Candidate->CanMergeToLSDouble) {
           MergeBaseUpdateLSMultiple(Merged);
       } else {
         for (MachineInstr *MI : Candidate->Instrs) {
           if (MergeBaseUpdateLoadStore(MI))
             Changed = true;
         }
       }
     } else {
       assert(Candidate->Instrs.size() == 1);
       if (MergeBaseUpdateLoadStore(Candidate->Instrs.front()))
         Changed = true;
     }
   }
   Candidates.clear();
   // Try to fold add/sub into the LDRD/STRD formed by ARMPreAllocLoadStoreOpt.
   for (MachineInstr *MI : MergeBaseCandidates)
     MergeBaseUpdateLSDouble(*MI);

test/CodeGen/ARM/load-multiple-opt.ll

+; RUN: llc %s -o - -debug-only=arm-ldst-opt | FileCheck %s
+; CHECK-NOT: vstmia r4, {d15, d16, d17, d18, d19, d20, d21, d22, d23, d24, d25, d26, d27, d28, d29, d30, d31}
+; CHECK:  vstmia r4, {d15, d16, d17, d18, d19, d20, d21, d22, d23, d24, d25, d26, d27, d28, d29, d30}
+; CHECK-NEXT:   vstr  d31, [r4, #128]
+; CHECK:  vstmia  r0, {d4, d5, d6, d7, d8, d9, d10, d11, d12, d13, d14}
+
+target datalayout = "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64"
+target triple = "thumbv7--linux-android"
+
+%struct.ak = type { %struct.bk }
+%struct.bk = type { %struct.m }
+%struct.m = type { [64 x %struct.bw] }
+%struct.bw = type { double, %struct.ak.1 }
+%struct.ak.1 = type { %struct.bk.2 }
+%struct.bk.2 = type { %struct.m.4 }
+%struct.m.4 = type { [64 x double] }
+%struct.l = type { i8 }
+
+; Function Attrs: ssp uwtable
+define void @_Z2brR1lI1ME(%struct.ak* noalias sret, %struct.l* nocapture readonly dereferenceable(1)) {
+  %3 = alloca %struct.bw, align 8
+  %4 = tail call %struct.ak* @_ZN2akI2bwEC1Ev(%struct.ak* %0)
+  %5 = bitcast %struct.bw* %3 to i8*
+  call void @llvm.lifetime.start.p0i8(i64 520, i8* nonnull %5)
+  %6 = call %struct.bw* @_ZN2bwC1Ed(%struct.bw* nonnull %3, double 2.000000e+00)
+  %7 = bitcast %struct.l* %1 to %struct.bw**
+  %8 = load %struct.bw*, %struct.bw** %7, align 4, !noalias !1
+  %9 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 0
+  %10 = load double, double* %9, align 8
+  %11 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 0
+  %12 = load double, double* %11, align 8
+  %13 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 1
+  %14 = load double, double* %13, align 8
+  %15 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 2
+  %16 = load double, double* %15, align 8
+  %17 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 3
+  %18 = load double, double* %17, align 8
+  %19 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 4
+  %20 = load double, double* %19, align 8
+  %21 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 5
+  %22 = load double, double* %21, align 8
+  %23 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 6
+  %24 = load double, double* %23, align 8
+  %25 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 7
+  %26 = load double, double* %25, align 8
+  %27 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 8
+  %28 = load double, double* %27, align 8
+  %29 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 9
+  %30 = load double, double* %29, align 8
+  %31 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 10
+  %32 = load double, double* %31, align 8
+  %33 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 11
+  %34 = load double, double* %33, align 8
+  %35 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 12
+  %36 = load double, double* %35, align 8
+  %37 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 13
+  %38 = load double, double* %37, align 8
+  %39 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 14
+  %40 = load double, double* %39, align 8
+  %41 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 15
+  %42 = load double, double* %41, align 8
+  %43 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 16
+  %44 = load double, double* %43, align 8
+  %45 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 17
+  %46 = load double, double* %45, align 8
+  %47 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 18
+  %48 = load double, double* %47, align 8
+  %49 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 19
+  %50 = load double, double* %49, align 8
+  %51 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 20
+  %52 = load double, double* %51, align 8
+  %53 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 21
+  %54 = load double, double* %53, align 8
+  %55 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 22
+  %56 = load double, double* %55, align 8
+  %57 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 23
+  %58 = load double, double* %57, align 8
+  %59 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 24
+  %60 = load double, double* %59, align 8
+  %61 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 25
+  %62 = load double, double* %61, align 8
+  %63 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 26
+  %64 = load double, double* %63, align 8
+  %65 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 27
+  %66 = load double, double* %65, align 8
+  %67 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 28
+  %68 = load double, double* %67, align 8
+  %69 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 29
+  %70 = load double, double* %69, align 8
+  %71 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 30
+  %72 = load double, double* %71, align 8
+  %73 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 31
+  %74 = load double, double* %73, align 8
+  %75 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 32
+  %76 = load double, double* %75, align 8
+  %77 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 33
+  %78 = load double, double* %77, align 8
+  %79 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 34
+  %80 = load double, double* %79, align 8
+  %81 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 35
+  %82 = load double, double* %81, align 8
+  %83 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 36
+  %84 = load double, double* %83, align 8
+  %85 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 37
+  %86 = load double, double* %85, align 8
+  %87 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 38
+  %88 = load double, double* %87, align 8
+  %89 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 39
+  %90 = load double, double* %89, align 8
+  %91 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 40
+  %92 = load double, double* %91, align 8
+  %93 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 41
+  %94 = load double, double* %93, align 8
+  %95 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 42
+  %96 = load double, double* %95, align 8
+  %97 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 43
+  %98 = load double, double* %97, align 8
+  %99 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 44
+  %100 = load double, double* %99, align 8
+  %101 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 45
+  %102 = load double, double* %101, align 8
+  %103 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 46
+  %104 = load double, double* %103, align 8
+  %105 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 47
+  %106 = load double, double* %105, align 8
+  %107 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 48
+  %108 = load double, double* %107, align 8
+  %109 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 49
+  %110 = load double, double* %109, align 8
+  %111 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 50
+  %112 = load double, double* %111, align 8
+  %113 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 51
+  %114 = load double, double* %113, align 8
+  %115 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 52
+  %116 = load double, double* %115, align 8
+  %117 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 53
+  %118 = load double, double* %117, align 8
+  %119 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 54
+  %120 = load double, double* %119, align 8
+  %121 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 55
+  %122 = load double, double* %121, align 8
+  %123 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 56
+  %124 = load double, double* %123, align 8
+  %125 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 57
+  %126 = load double, double* %125, align 8
+  %127 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 58
+  %128 = load double, double* %127, align 8
+  %129 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 59
+  %130 = load double, double* %129, align 8
+  %131 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 60
+  %132 = load double, double* %131, align 8
+  %133 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 61
+  %134 = load double, double* %133, align 8
+  %135 = getelementptr inbounds %struct.bw, %struct.bw* %8, i32 2, i32 1, i32 0, i32 0, i32 0, i32 62
+  %136 = load double, double* %135, align 8
+  %137 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 0
+  store double %10, double* %137, align 8
+  %138 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 0
+  store double %12, double* %138, align 8
+  %139 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 1
+  store double %14, double* %139, align 8
+  %140 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 2
+  store double %16, double* %140, align 8
+  %141 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 3
+  store double %18, double* %141, align 8
+  %142 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 4
+  store double %20, double* %142, align 8
+  %143 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 5
+  store double %22, double* %143, align 8
+  %144 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 6
+  store double %24, double* %144, align 8
+  %145 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 7
+  store double %26, double* %145, align 8
+  %146 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 8
+  store double %28, double* %146, align 8
+  %147 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 9
+  store double %30, double* %147, align 8
+  %148 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 10
+  store double %32, double* %148, align 8
+  %149 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 11
+  store double %34, double* %149, align 8
+  %150 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 12
+  store double %36, double* %150, align 8
+  %151 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 13
+  store double %38, double* %151, align 8
+  %152 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 14
+  store double %40, double* %152, align 8
+  %153 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 15
+  store double %42, double* %153, align 8
+  %154 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 16
+  store double %44, double* %154, align 8
+  %155 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 17
+  store double %46, double* %155, align 8
+  %156 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 18
+  store double %48, double* %156, align 8
+  %157 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 19
+  store double %50, double* %157, align 8
+  %158 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 20
+  store double %52, double* %158, align 8
+  %159 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 21
+  store double %54, double* %159, align 8
+  %160 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 22
+  store double %56, double* %160, align 8
+  %161 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 23
+  store double %58, double* %161, align 8
+  %162 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 24
+  store double %60, double* %162, align 8
+  %163 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 25
+  store double %62, double* %163, align 8
+  %164 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 26
+  store double %64, double* %164, align 8
+  %165 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 27
+  store double %66, double* %165, align 8
+  %166 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 28
+  store double %68, double* %166, align 8
+  %167 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 29
+  store double %70, double* %167, align 8
+  %168 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 30
+  store double %72, double* %168, align 8
+  %169 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 31
+  store double %74, double* %169, align 8
+  %170 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 32
+  store double %76, double* %170, align 8
+  %171 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 33
+  store double %78, double* %171, align 8
+  %172 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 34
+  store double %80, double* %172, align 8
+  %173 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 35
+  store double %82, double* %173, align 8
+  %174 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 36
+  store double %84, double* %174, align 8
+  %175 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 37
+  store double %86, double* %175, align 8
+  %176 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 38
+  store double %88, double* %176, align 8
+  %177 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 39
+  store double %90, double* %177, align 8
+  %178 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 40
+  store double %92, double* %178, align 8
+  %179 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 41
+  store double %94, double* %179, align 8
+  %180 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 42
+  store double %96, double* %180, align 8
+  %181 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 43
+  store double %98, double* %181, align 8
+  %182 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 44
+  store double %100, double* %182, align 8
+  %183 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 45
+  store double %102, double* %183, align 8
+  %184 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 46
+  store double %104, double* %184, align 8
+  %185 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 47
+  store double %106, double* %185, align 8
+  %186 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 48
+  store double %108, double* %186, align 8
+  %187 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 49
+  store double %110, double* %187, align 8
+  %188 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 50
+  store double %112, double* %188, align 8
+  %189 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 51
+  store double %114, double* %189, align 8
+  %190 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 52
+  store double %116, double* %190, align 8
+  %191 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 53
+  store double %118, double* %191, align 8
+  %192 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 54
+  store double %120, double* %192, align 8
+  %193 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 55
+  store double %122, double* %193, align 8
+  %194 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 56
+  store double %124, double* %194, align 8
+  %195 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 57
+  store double %126, double* %195, align 8
+  %196 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 58
+  store double %128, double* %196, align 8
+  %197 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 59
+  store double %130, double* %197, align 8
+  %198 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 60
+  store double %132, double* %198, align 8
+  %199 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 61
+  store double %134, double* %199, align 8
+  %200 = getelementptr inbounds %struct.ak, %struct.ak* %0, i32 0, i32 0, i32 0, i32 0, i32 undef, i32 1, i32 0, i32 0, i32 0, i32 62
+  store double %136, double* %200, align 8
+  call void @llvm.lifetime.end.p0i8(i64 520, i8* nonnull %5)
+  ret void
+}
+
+declare %struct.ak* @_ZN2akI2bwEC1Ev(%struct.ak* returned)
+
+declare void @llvm.lifetime.start.p0i8(i64, i8* nocapture)
+
+declare %struct.bw* @_ZN2bwC1Ed(%struct.bw* returned, double)
+
+declare void @llvm.lifetime.end.p0i8(i64, i8* nocapture)
+
+!1 = !{!2, !4}
+!2 = distinct !{!2, !3, !"_ZNK1M2asEi: argument 0"}
+!3 = distinct !{!3, !"_ZNK1M2asEi"}
+!4 = distinct !{!4, !5, !"_ZNK1lI1ME3fooEi: argument 0"}
+!5 = distinct !{!5, !"_ZNK1lI1ME3fooEi"}

test/CodeGen/ARM/load_store_opt_reg_limit.mir

+# RUN: llc -mtriple=thumbv7--linux-andorid -verify-machineinstrs -run-pass=arm-ldst-opt %s -o - | FileCheck %s
+--- |
+  target datalayout = "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64"
+  target triple = "thumbv7--linux-android"
+
+  define void @_Z2brR1lI1ME() {
+    ret void
+  }
+
+...
+---
+#CHECK: _Z2brR1lI1ME
+name:            _Z2brR1lI1ME
+# CHECK: VSTMDIA $r4, 14, $noreg,  $d15,  $d16,  $d17,  $d18,  $d19,  $d20,  $d21,  $d22,  $d23,  $d24,  $d25,  $d26,  $d27,  $d28,  $d29,  $d30
+# CHECK-NEXT: VSTRD  $d31, $r4, 32, 14, $noreg :: (store 8)
+# CHECK:     VSTMDIA killed $r0, 14, $noreg,  $d4,  $d5,  $d6,  $d7,  $d8,  $d9,  $d10,  $d11,  $d12,  $d13,  $d14
+body:             |
+  bb.0:
+    VSTRD  $d15, $r4, 0, 14, $noreg :: (store 8)
+    VSTRD  $d16, $r4, 2, 14, $noreg :: (store 8)
+    VSTRD  $d17, $r4, 4, 14, $noreg :: (store 8)
+    VSTRD  $d18, $r4, 6, 14, $noreg :: (store 8)
+    VSTRD  $d19, $r4, 8, 14, $noreg :: (store 8)
+    VSTRD  $d20, $r4, 10, 14, $noreg :: (store 8)
+    VSTRD  $d21, $r4, 12, 14, $noreg :: (store 8)
+    VSTRD  $d22, $r4, 14, 14, $noreg :: (store 8)
+    VSTRD  $d23, $r4, 16, 14, $noreg :: (store 8)
+    VSTRD  $d24, $r4, 18, 14, $noreg :: (store 8)
+    VSTRD  $d25, $r4, 20, 14, $noreg :: (store 8)
+    VSTRD  $d26, $r4, 22, 14, $noreg :: (store 8)
+    VSTRD  $d27, $r4, 24, 14, $noreg :: (store 8)
+    VSTRD  $d28, $r4, 26, 14, $noreg :: (store 8)
+    VSTRD  $d29, $r4, 28, 14, $noreg :: (store 8)
+    VSTRD  $d30, $r4, 30, 14, $noreg :: (store 8)
+    VSTRD  $d31, $r4, 32, 14, $noreg :: (store 8)
+    VSTRD  $d0, $r4, 34, 14, $noreg :: (store 8)
+    VSTRD  $d1, $r4, 36, 14, $noreg :: (store 8)
+    VSTRD  $d3, $r4, 38, 14, $noreg :: (store 8)
+    VSTRD  $d2, $r4, 40, 14, $noreg :: (store 8)
+    VSTRD  $d4, $r4, 42, 14, $noreg :: (store 8)
+    VSTRD  $d5, $r4, 44, 14, $noreg :: (store 8)
+    VSTRD  $d6, $r4, 46, 14, $noreg :: (store 8)
+    VSTRD  $d7, $r4, 48, 14, $noreg :: (store 8)
+    VSTRD  $d8, $r4, 50, 14, $noreg :: (store 8)
+    VSTRD  $d9, $r4, 52, 14, $noreg :: (store 8)
+    VSTRD  $d10, $r4, 54, 14, $noreg :: (store 8)
+    VSTRD  $d11, $r4, 56, 14, $noreg :: (store 8)
+    VSTRD  $d12, $r4, 58, 14, $noreg :: (store 8)
+    VSTRD  $d13, $r4, 60, 14, $noreg :: (store 8)
+    VSTRD  $d14, $r4, 62, 14, $noreg :: (store 8)
+...