[BitcodeReader] Fix DelayedShuffle handling for ConstantExpr shuffles.

[efriedma]

Summary

The indexing was messed up, so the result was completely broken.

Shuffle constant exprs are rare in practice; without vscale types, constant folding generally elminates them. So sort of hard to trip over.

Fixes regression from D72467.

[efriedma]

Ping

[jdoerfert]

I'm not an expert in this but it looks reasonable and tested. LGTM

[vitalybuka]

There is a memory leak
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-fast/builds/43111/steps/check-llvm%20asan/logs/stdio

[hctim]

Reverted in 10045cbe01928d9281723c640c03984d540f9012 to bring the ASan bots green again.

[efriedma]

Posted https://reviews.llvm.org/D82509 .

[morehouse]

Still memory leaks: http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-fast/builds/43341

FAIL: LLVM :: Bitcode/vscale-shuffle.ll (6510 of 38183)
******************** TEST 'LLVM :: Bitcode/vscale-shuffle.ll' FAILED ********************
Script:
--
: 'RUN: at line 1';   /b/sanitizer-x86_64-linux-fast/build/llvm_build_asan/bin/llvm-as < /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/test/Bitcode/vscale-shuffle.ll | /b/sanitizer-x86_64-linux-fast/build/llvm_build_asan/bin/llvm-dis -disable-output
: 'RUN: at line 2';   /b/sanitizer-x86_64-linux-fast/build/llvm_build_asan/bin/verify-uselistorder < /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/test/Bitcode/vscale-shuffle.ll
--
Exit Code: 1

Command Output (stderr):
--

=================================================================
==42464==ERROR: LeakSanitizer: detected memory leaks

Direct leak of 64 byte(s) in 1 object(s) allocated from:
    #0 0x4cbc2d in malloc /b/s/w/ir/cache/builder/src/third_party/llvm/compiler-rt/lib/asan/asan_malloc_linux.cpp:145:3
    #1 0xbeea32 in safe_malloc /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/include/llvm/Support/MemAlloc.h:26:18
    #2 0xbeea32 in llvm::SmallVectorBase<unsigned int>::grow_pod(void*, unsigned long, unsigned long) /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/Support/SmallVector.cpp:68:15
    #3 0x8736f2 in grow_pod /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/include/llvm/ADT/SmallVector.h:119:11
    #4 0x8736f2 in grow /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/include/llvm/ADT/SmallVector.h:345:41
    #5 0x8736f2 in append<const int *, void> /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/include/llvm/ADT/SmallVector.h:436:13
    #6 0x8736f2 in assign<const int *, void> /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/include/llvm/ADT/SmallVector.h:472:5
    #7 0x8736f2 in llvm::ShuffleVectorConstantExpr::ShuffleVectorConstantExpr(llvm::Constant*, llvm::Constant*, llvm::ArrayRef<int>) /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/IR/ConstantsContext.h:159:17
    #8 0x87136c in llvm::ConstantExprKeyType::create(llvm::Type*) const /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/IR/ConstantsContext.h:582:18
    #9 0x84ec5c in create /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/IR/ConstantsContext.h:672:31
    #10 0x84ec5c in llvm::ConstantUniqueMap<llvm::ConstantExpr>::getOrCreate(llvm::Type*, llvm::ConstantExprKeyType) /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/IR/ConstantsContext.h:691:16
    #11 0x841827 in llvm::ConstantExpr::getShuffleVector(llvm::Constant*, llvm::Constant*, llvm::ArrayRef<int>, llvm::Type*) /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/IR/Constants.cpp:2390:31
    #12 0x554a79 in llvm::LLParser::ParseValID(llvm::ValID&, llvm::LLParser::PerFunctionState*) /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/AsmParser/LLParser.cpp:3717:24
    #13 0x59cb21 in llvm::LLParser::ParseValue(llvm::Type*, llvm::Value*&, llvm::LLParser::PerFunctionState*) /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/AsmParser/LLParser.cpp:5395:10
    #14 0x56e78e in ParseValue /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/AsmParser/LLParser.h:467:14
    #15 0x56e78e in llvm::LLParser::ParseParameterList(llvm::SmallVectorImpl<llvm::LLParser::ParamInfo>&, llvm::LLParser::PerFunctionState&, bool, bool) /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/AsmParser/LLParser.cpp:2533:48
    #16 0x5b6b1e in llvm::LLParser::ParseCall(llvm::Instruction*&, llvm::LLParser::PerFunctionState&, llvm::CallInst::TailCallKind) /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/AsmParser/LLParser.cpp:6911:7
    #17 0x59f3ea in llvm::LLParser::ParseInstruction(llvm::Instruction*&, llvm::BasicBlock*, llvm::LLParser::PerFunctionState&) /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/AsmParser/LLParser.cpp
    #18 0x59e378 in llvm::LLParser::ParseBasicBlock(llvm::LLParser::PerFunctionState&) /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/AsmParser/LLParser.cpp:5771:13
    #19 0x53c00d in llvm::LLParser::ParseFunctionBody(llvm::Function&) /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/AsmParser/LLParser.cpp:5716:9
    #20 0x528efd in llvm::LLParser::ParseDefine() /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/AsmParser/LLParser.cpp:529:10
    #21 0x521855 in llvm::LLParser::ParseTopLevelEntities() /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/AsmParser/LLParser.cpp:347:33
    #22 0x521525 in llvm::LLParser::Run(bool, llvm::function_ref<llvm::Optional<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > > (llvm::StringRef)>) /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/AsmParser/LLParser.cpp:80:10
    #23 0x4fc6a4 in parseAssemblyInto(llvm::MemoryBufferRef, llvm::Module*, llvm::ModuleSummaryIndex*, llvm::SMDiagnostic&, llvm::SlotMapping*, bool, llvm::function_ref<llvm::Optional<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > > (llvm::StringRef)>) /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/AsmParser/Parser.cpp:36:8
    #24 0x4fd609 in parseAssemblyWithIndex(llvm::MemoryBufferRef, llvm::SMDiagnostic&, llvm::LLVMContext&, llvm::SlotMapping*, bool, llvm::function_ref<llvm::Optional<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > > (llvm::StringRef)>) /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/AsmParser/Parser.cpp:85:7
    #25 0x4fde4f in parseAssemblyFileWithIndex(llvm::StringRef, llvm::SMDiagnostic&, llvm::LLVMContext&, llvm::SlotMapping*, bool, llvm::function_ref<llvm::Optional<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > > (llvm::StringRef)>) /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/AsmParser/Parser.cpp:114:10
    #26 0x4fd92f in llvm::parseAssemblyFileWithIndex(llvm::StringRef, llvm::SMDiagnostic&, llvm::LLVMContext&, llvm::SlotMapping*, llvm::function_ref<llvm::Optional<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > > (llvm::StringRef)>) /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/AsmParser/Parser.cpp:123:10
    #27 0x4f88f4 in main /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/tools/llvm-as/llvm-as.cpp:134:22
    #28 0x7fd933d4509a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)

SUMMARY: AddressSanitizer: 64 byte(s) leaked in 1 allocation(s).

=================================================================
==42465==ERROR: LeakSanitizer: detected memory leaks

Direct leak of 64 byte(s) in 1 object(s) allocated from:
    #0 0x4ab46d in malloc /b/s/w/ir/cache/builder/src/third_party/llvm/compiler-rt/lib/asan/asan_malloc_linux.cpp:145:3
    #1 0xa27f62 in safe_malloc /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/include/llvm/Support/MemAlloc.h:26:18
    #2 0xa27f62 in llvm::SmallVectorBase<unsigned int>::grow_pod(void*, unsigned long, unsigned long) /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/Support/SmallVector.cpp:68:15
    #3 0x720ac2 in grow_pod /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/include/llvm/ADT/SmallVector.h:119:11
    #4 0x720ac2 in grow /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/include/llvm/ADT/SmallVector.h:345:41
    #5 0x720ac2 in append<const int *, void> /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/include/llvm/ADT/SmallVector.h:436:13
    #6 0x720ac2 in assign<const int *, void> /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/include/llvm/ADT/SmallVector.h:472:5
    #7 0x720ac2 in llvm::ShuffleVectorConstantExpr::ShuffleVectorConstantExpr(llvm::Constant*, llvm::Constant*, llvm::ArrayRef<int>) /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/IR/ConstantsContext.h:159:17
    #8 0x71e73c in llvm::ConstantExprKeyType::create(llvm::Type*) const /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/IR/ConstantsContext.h:582:18
    #9 0x6fc45c in create /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/IR/ConstantsContext.h:672:31
    #10 0x6fc45c in llvm::ConstantUniqueMap<llvm::ConstantExpr>::getOrCreate(llvm::Type*, llvm::ConstantExprKeyType) /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/IR/ConstantsContext.h:691:16
    #11 0x6ef607 in llvm::ConstantExpr::getShuffleVector(llvm::Constant*, llvm::Constant*, llvm::ArrayRef<int>, llvm::Type*) /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/IR/Constants.cpp:2390:31
    #12 0x536cbf in (anonymous namespace)::BitcodeReader::parseConstants() /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/Bitcode/Reader/BitcodeReader.cpp:2374:20
    #13 0x5086bc in (anonymous namespace)::BitcodeReader::parseFunctionBody(llvm::Function*) /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/Bitcode/Reader/BitcodeReader.cpp:3822:25
    #14 0x4ffecb in (anonymous namespace)::BitcodeReader::materialize(llvm::GlobalValue*) /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/Bitcode/Reader/BitcodeReader.cpp:5347:19
    #15 0x502606 in (anonymous namespace)::BitcodeReader::materializeModule() /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/Bitcode/Reader/BitcodeReader.cpp:5405:21
    #16 0x845dc7 in llvm::Module::materializeAll() /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/lib/IR/Module.cpp:449:13
    #17 0x4d8ebe in main /b/sanitizer-x86_64-linux-fast/build/llvm-project/llvm/tools/llvm-dis/llvm-dis.cpp:176:20
    #18 0x7ffb42ae009a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)

SUMMARY: AddressSanitizer: 64 byte(s) leaked in 1 allocation(s).

[efriedma]

Should actually be fixed with 779e4d8

llvm/lib/Bitcode/Reader/BitcodeReader.cpp

Error BitcodeReader::parseConstants() {
 
   struct DelayedShufTy {
     VectorType *OpTy;
     VectorType *RTy;
     Type *CurFullTy;
     uint64_t Op0Idx;
     uint64_t Op1Idx;
     uint64_t Op2Idx;
+    unsigned CstNo;
   };
   std::vector<DelayedShufTy> DelayedShuffles;
   while (true) {
     Expected<BitstreamEntry> MaybeEntry = Stream.advanceSkippingSubblocks();
     if (!MaybeEntry)
       return MaybeEntry.takeError();
     BitstreamEntry Entry = MaybeEntry.get();
 
     switch (Entry.Kind) {
     case BitstreamEntry::SubBlock: // Handled for us already.
     case BitstreamEntry::Error:
       return error("Malformed block");
     case BitstreamEntry::EndBlock:
-      if (NextCstNo != ValueList.size())
-        return error("Invalid constant reference");
-
       // Once all the constants have been read, go through and resolve forward
       // references.
       //
       // We have to treat shuffles specially because they don't have three
       // operands anymore.  We need to convert the shuffle mask into an array,
       // and we can't convert a forward reference.
       for (auto &DelayedShuffle : DelayedShuffles) {
         VectorType *OpTy = DelayedShuffle.OpTy;
         VectorType *RTy = DelayedShuffle.RTy;
         uint64_t Op0Idx = DelayedShuffle.Op0Idx;
         uint64_t Op1Idx = DelayedShuffle.Op1Idx;
         uint64_t Op2Idx = DelayedShuffle.Op2Idx;
+        uint64_t CstNo = DelayedShuffle.CstNo;
         Constant *Op0 = ValueList.getConstantFwdRef(Op0Idx, OpTy);
         Constant *Op1 = ValueList.getConstantFwdRef(Op1Idx, OpTy);
         Type *ShufTy =
             VectorType::get(Type::getInt32Ty(Context), RTy->getElementCount());
         Constant *Op2 = ValueList.getConstantFwdRef(Op2Idx, ShufTy);
         if (!ShuffleVectorInst::isValidOperands(Op0, Op1, Op2))
           return error("Invalid shufflevector operands");
         SmallVector<int, 16> Mask;
         ShuffleVectorInst::getShuffleMask(Op2, Mask);
         Value *V = ConstantExpr::getShuffleVector(Op0, Op1, Mask);
-        ValueList.assignValue(V, NextCstNo, DelayedShuffle.CurFullTy);
-        ++NextCstNo;
+        ValueList.assignValue(V, CstNo, DelayedShuffle.CurFullTy);
       }
+
+      if (NextCstNo != ValueList.size())
+        return error("Invalid constant reference");
+
       ValueList.resolveConstantForwardRefs();
       return Error::success();
     case BitstreamEntry::Record:
       // The interesting case.
       break;
     }
 
     // Read a record.
case bitc::CST_CODE_CE_INSERTELT
       V = ConstantExpr::getInsertElement(Op0, Op1, Op2);
       break;
     }
     case bitc::CST_CODE_CE_SHUFFLEVEC: { // CE_SHUFFLEVEC: [opval, opval, opval]
       VectorType *OpTy = dyn_cast<VectorType>(CurTy);
       if (Record.size() < 3 || !OpTy)
         return error("Invalid record");
       DelayedShuffles.push_back(
-          {OpTy, OpTy, CurFullTy, Record[0], Record[1], Record[2]});
+          {OpTy, OpTy, CurFullTy, Record[0], Record[1], Record[2], NextCstNo});
+      ++NextCstNo;
       continue;
     }
     case bitc::CST_CODE_CE_SHUFVEC_EX: { // [opty, opval, opval, opval]
       VectorType *RTy = dyn_cast<VectorType>(CurTy);
       VectorType *OpTy =
         dyn_cast_or_null<VectorType>(getTypeByID(Record[0]));
       if (Record.size() < 4 || !RTy || !OpTy)
         return error("Invalid record");
       DelayedShuffles.push_back(
-          {OpTy, RTy, CurFullTy, Record[1], Record[2], Record[3]});
+          {OpTy, RTy, CurFullTy, Record[1], Record[2], Record[3], NextCstNo});
+      ++NextCstNo;
       continue;
     }
     case bitc::CST_CODE_CE_CMP: {     // CE_CMP: [opty, opval, opval, pred]
       if (Record.size() < 4)
         return error("Invalid record");
       Type *OpTy = getTypeByID(Record[0]);
       if (!OpTy)
         return error("Invalid record");

llvm/test/Bitcode/vscale-shuffle.ll

+; RUN: llvm-as < %s | llvm-dis -disable-output
+; RUN: verify-uselistorder < %s
+
+define void @f() {
+  %l = call <vscale x 16 x i8> @l(<vscale x 16 x i1> shufflevector (<vscale x 16 x i1> insertelement (<vscale x 16 x i1> undef, i1 true, i32 0), <vscale x 16 x i1> undef, <vscale x 16 x i32> zeroinitializer))
+  %i = add <vscale x 2 x i64> undef, shufflevector (<vscale x 2 x i64> insertelement (<vscale x 2 x i64> undef, i64 1, i32 0), <vscale x 2 x i64> undef, <vscale x 2 x i32> zeroinitializer)
+  unreachable
+}
+
+declare <vscale x 16 x i8> @l(<vscale x 16 x i1>)