rustc: Update LLVM

This commit updates the LLVM submodule in use to the current HEAD of the LLVM
repository. This is primarily being done to start picking up unwinding support
for MSVC, which is currently unimplemented in the revision of LLVM we are using.
Along the way a few changes had to be made:

* As usual, lots of C++ debuginfo bindings in LLVM changed, so there were some
  significant changes to our RustWrapper.cpp
* As usual, some pass management changed in LLVM, so clang was re-scrutinized to
  ensure that we're doing the same thing as clang.
* Some optimization options are now passed directly into the
  `PassManagerBuilder` instead of through CLI switches to LLVM.
* The `NoFramePointerElim` option was removed from LLVM, favoring instead the
  `no-frame-pointer-elim` function attribute instead.

Additionally, LLVM has picked up some new optimizations which required fixing an
existing soundness hole in the IR we generate. It appears that the current LLVM
we use does not expose this hole. When an enum is moved, the previous slot in
memory is overwritten with a bit pattern corresponding to "dropped". When the
drop glue for this slot is run, however, the switch on the discriminant can
often start executing the `unreachable` block of the switch due to the
discriminant now being outside the normal range. This was patched over locally
for now by having the `unreachable` block just change to a `ret void`.

1 files changed, 115 insertions, 31 deletions

diff --git a/src/rustllvm/RustWrapper.cpp b/src/rustllvm/RustWrapper.cpp
index ad6533e5480..70ef64afc43 100644
--- a/src/rustllvm/RustWrapper.cpp
+++ b/src/rustllvm/RustWrapper.cpp
@@ -141,6 +141,15 @@ extern "C" void LLVMAddFunctionAttrString(LLVMValueRef Fn, unsigned index, const
   F->addAttributes(index, AttributeSet::get(F->getContext(), index, B));
 }
 
+extern "C" void LLVMAddFunctionAttrStringValue(LLVMValueRef Fn, unsigned index,
+                                               const char *Name,
+                                               const char *Value) {
+  Function *F = unwrap<Function>(Fn);
+  AttrBuilder B;
+  B.addAttribute(Name, Value);
+  F->addAttributes(index, AttributeSet::get(F->getContext(), index, B));
+}
+
 extern "C" void LLVMRemoveFunctionAttrString(LLVMValueRef fn, unsigned index, const char *Name) {
   Function *f = unwrap<Function>(fn);
   LLVMContext &C = f->getContext();
@@ -229,9 +238,24 @@ typedef LLVMValueRef LLVMMetadataRef;
 #endif
 
 template<typename DIT>
+DIT* unwrapDIptr(LLVMMetadataRef ref) {
+    return (DIT*) (ref ? unwrap<MDNode>(ref) : NULL);
+}
+
+#if LLVM_VERSION_MINOR <= 6
+template<typename DIT>
 DIT unwrapDI(LLVMMetadataRef ref) {
     return DIT(ref ? unwrap<MDNode>(ref) : NULL);
 }
+#else
+#define DIDescriptor DIScope
+#define DIArray DINodeArray
+#define unwrapDI unwrapDIptr
+#endif
+
+#if LLVM_VERSION_MINOR <= 5
+#define DISubroutineType DICompositeType
+#endif
 
 extern "C" uint32_t LLVMRustDebugMetadataVersion() {
     return DEBUG_METADATA_VERSION;
@@ -296,7 +320,9 @@ extern "C" LLVMMetadataRef LLVMDIBuilderCreateSubroutineType(
     LLVMMetadataRef ParameterTypes) {
     return wrap(Builder->createSubroutineType(
         unwrapDI<DIFile>(File),
-#if LLVM_VERSION_MINOR >= 6
+#if LLVM_VERSION_MINOR >= 7
+        DITypeRefArray(unwrap<MDTuple>(ParameterTypes))));
+#elif LLVM_VERSION_MINOR >= 6
         unwrapDI<DITypeArray>(ParameterTypes)));
 #else
         unwrapDI<DIArray>(ParameterTypes)));
@@ -322,11 +348,11 @@ extern "C" LLVMMetadataRef LLVMDIBuilderCreateFunction(
     return wrap(Builder->createFunction(
         unwrapDI<DIScope>(Scope), Name, LinkageName,
         unwrapDI<DIFile>(File), LineNo,
-        unwrapDI<DICompositeType>(Ty), isLocalToUnit, isDefinition, ScopeLine,
+        unwrapDI<DISubroutineType>(Ty), isLocalToUnit, isDefinition, ScopeLine,
         Flags, isOptimized,
         unwrap<Function>(Fn),
-        unwrapDI<MDNode*>(TParam),
-        unwrapDI<MDNode*>(Decl)));
+        unwrapDIptr<MDNode>(TParam),
+        unwrapDIptr<MDNode>(Decl)));
 }
 
 extern "C" LLVMMetadataRef LLVMDIBuilderCreateBasicType(
@@ -373,7 +399,11 @@ extern "C" LLVMMetadataRef LLVMDIBuilderCreateStructType(
         AlignInBits,
         Flags,
         unwrapDI<DIType>(DerivedFrom),
+#if LLVM_VERSION_MINOR >= 7
+        DINodeArray(unwrapDI<MDTuple>(Elements)),
+#else
         unwrapDI<DIArray>(Elements),
+#endif
         RunTimeLang,
         unwrapDI<DIType>(VTableHolder),
         UniqueId
@@ -436,7 +466,7 @@ extern "C" LLVMMetadataRef LLVMDIBuilderCreateStaticVariable(
         unwrapDI<DIType>(Ty),
         isLocalToUnit,
         cast<Constant>(unwrap(Val)),
-        unwrapDI<MDNode*>(Decl)));
+        unwrapDIptr<MDNode>(Decl)));
 }
 
 extern "C" LLVMMetadataRef LLVMDIBuilderCreateVariable(
@@ -486,7 +516,12 @@ extern "C" LLVMMetadataRef LLVMDIBuilderCreateArrayType(
     LLVMMetadataRef Subscripts) {
     return wrap(Builder->createArrayType(Size, AlignInBits,
         unwrapDI<DIType>(Ty),
-        unwrapDI<DIArray>(Subscripts)));
+#if LLVM_VERSION_MINOR >= 7
+        DINodeArray(unwrapDI<MDTuple>(Subscripts))
+#else
+        unwrapDI<DIArray>(Subscripts)
+#endif
+    ));
 }
 
 extern "C" LLVMMetadataRef LLVMDIBuilderCreateVectorType(
@@ -497,7 +532,12 @@ extern "C" LLVMMetadataRef LLVMDIBuilderCreateVectorType(
     LLVMMetadataRef Subscripts) {
     return wrap(Builder->createVectorType(Size, AlignInBits,
         unwrapDI<DIType>(Ty),
-        unwrapDI<DIArray>(Subscripts)));
+#if LLVM_VERSION_MINOR >= 7
+        DINodeArray(unwrapDI<MDTuple>(Subscripts))
+#else
+        unwrapDI<DIArray>(Subscripts)
+#endif
+    ));
 }
 
 extern "C" LLVMMetadataRef LLVMDIBuilderGetOrCreateSubrange(
@@ -511,12 +551,18 @@ extern "C" LLVMMetadataRef LLVMDIBuilderGetOrCreateArray(
     DIBuilderRef Builder,
     LLVMMetadataRef* Ptr,
     unsigned Count) {
+#if LLVM_VERSION_MINOR >= 7
+    Metadata **DataValue = unwrap(Ptr);
+    return wrap(Builder->getOrCreateArray(
+        ArrayRef<Metadata*>(DataValue, Count)).get());
+#else
     return wrap(Builder->getOrCreateArray(
 #if LLVM_VERSION_MINOR >= 6
         ArrayRef<Metadata*>(unwrap(Ptr), Count)));
 #else
         ArrayRef<Value*>(reinterpret_cast<Value**>(Ptr), Count)));
 #endif
+#endif
 }
 
 extern "C" LLVMValueRef LLVMDIBuilderInsertDeclareAtEnd(
@@ -525,21 +571,21 @@ extern "C" LLVMValueRef LLVMDIBuilderInsertDeclareAtEnd(
     LLVMMetadataRef VarInfo,
     int64_t* AddrOps,
     unsigned AddrOpsCount,
+    LLVMValueRef DL,
     LLVMBasicBlockRef InsertAtEnd) {
-#if LLVM_VERSION_MINOR >= 6
-    DIExpression Expr;
-    if (AddrOpsCount == 0) {
-      Expr = Builder->createExpression();
-    } else {
-      llvm::ArrayRef<int64_t> addr_ops(AddrOps, AddrOpsCount);
-      Expr = Builder->createExpression(addr_ops);
-    }
-#endif
     return wrap(Builder->insertDeclare(
         unwrap(Val),
+#if LLVM_VERSION_MINOR >= 7
+        unwrap<DILocalVariable>(VarInfo),
+#else
         unwrapDI<DIVariable>(VarInfo),
+#endif
 #if LLVM_VERSION_MINOR >= 6
-        Expr,
+        Builder->createExpression(
+          llvm::ArrayRef<int64_t>(AddrOps, AddrOpsCount)),
+#endif
+#if LLVM_VERSION_MINOR >= 7
+        DebugLoc(cast<MDNode>(unwrap<MetadataAsValue>(DL)->getMetadata())),
 #endif
         unwrap(InsertAtEnd)));
 }
@@ -550,21 +596,23 @@ extern "C" LLVMValueRef LLVMDIBuilderInsertDeclareBefore(
     LLVMMetadataRef VarInfo,
     int64_t* AddrOps,
     unsigned AddrOpsCount,
+    LLVMValueRef DL,
     LLVMValueRef InsertBefore) {
 #if LLVM_VERSION_MINOR >= 6
-    DIExpression Expr;
-    if (AddrOpsCount == 0) {
-      Expr = Builder->createExpression();
-    } else {
-      llvm::ArrayRef<int64_t> addr_ops(AddrOps, AddrOpsCount);
-      Expr = Builder->createExpression(addr_ops);
-    }
 #endif
     return wrap(Builder->insertDeclare(
         unwrap(Val),
+#if LLVM_VERSION_MINOR >= 7
+        unwrap<DILocalVariable>(VarInfo),
+#else
         unwrapDI<DIVariable>(VarInfo),
+#endif
 #if LLVM_VERSION_MINOR >= 6
-        Expr,
+        Builder->createExpression(
+          llvm::ArrayRef<int64_t>(AddrOps, AddrOpsCount)),
+#endif
+#if LLVM_VERSION_MINOR >= 7
+        DebugLoc(cast<MDNode>(unwrap<MetadataAsValue>(DL)->getMetadata())),
 #endif
         unwrap<Instruction>(InsertBefore)));
 }
@@ -595,7 +643,11 @@ extern "C" LLVMMetadataRef LLVMDIBuilderCreateEnumerationType(
         LineNumber,
         SizeInBits,
         AlignInBits,
+#if LLVM_VERSION_MINOR >= 7
+        DINodeArray(unwrapDI<MDTuple>(Elements)),
+#else
         unwrapDI<DIArray>(Elements),
+#endif
         unwrapDI<DIType>(ClassType)));
 }
 
@@ -620,7 +672,11 @@ extern "C" LLVMMetadataRef LLVMDIBuilderCreateUnionType(
         SizeInBits,
         AlignInBits,
         Flags,
+#if LLVM_VERSION_MINOR >= 7
+        DINodeArray(unwrapDI<MDTuple>(Elements)),
+#else
         unwrapDI<DIArray>(Elements),
+#endif
         RunTimeLang,
         UniqueId
         ));
@@ -638,10 +694,14 @@ extern "C" LLVMMetadataRef LLVMDIBuilderCreateTemplateTypeParameter(
     return wrap(Builder->createTemplateTypeParameter(
       unwrapDI<DIDescriptor>(Scope),
       Name,
-      unwrapDI<DIType>(Ty),
+      unwrapDI<DIType>(Ty)
+#if LLVM_VERSION_MINOR <= 6
+      ,
       unwrapDI<MDNode*>(File),
       LineNo,
-      ColumnNo));
+      ColumnNo
+#endif
+      ));
 }
 
 extern "C" int64_t LLVMDIBuilderCreateOpDeref()
@@ -673,7 +733,10 @@ extern "C" void LLVMDICompositeTypeSetTypeArray(
     LLVMMetadataRef CompositeType,
     LLVMMetadataRef TypeArray)
 {
-#if LLVM_VERSION_MINOR >= 6
+#if LLVM_VERSION_MINOR >= 7
+    DICompositeType *tmp = unwrapDI<DICompositeType>(CompositeType);
+    Builder->replaceArrays(tmp, DINodeArray(unwrap<MDTuple>(TypeArray)));
+#elif LLVM_VERSION_MINOR >= 6
     DICompositeType tmp = unwrapDI<DICompositeType>(CompositeType);
     Builder->replaceArrays(tmp, unwrapDI<DIArray>(TypeArray));
 #else
@@ -692,11 +755,15 @@ extern "C" LLVMValueRef LLVMDIBuilderCreateDebugLocation(
 
     DebugLoc debug_loc = DebugLoc::get(Line,
                                        Column,
-                                       unwrapDI<MDNode*>(Scope),
-                                       unwrapDI<MDNode*>(InlinedAt));
+                                       unwrapDIptr<MDNode>(Scope),
+                                       unwrapDIptr<MDNode>(InlinedAt));
 
 #if LLVM_VERSION_MINOR >= 6
-    return wrap(MetadataAsValue::get(context, debug_loc.getAsMDNode(context)));
+    return wrap(MetadataAsValue::get(context, debug_loc.getAsMDNode(
+#if LLVM_VERSION_MINOR <= 6
+            context
+#endif
+        )));
 #else
     return wrap(debug_loc.getAsMDNode(context));
 #endif
@@ -721,7 +788,12 @@ LLVMRustLinkInExternalBitcode(LLVMModuleRef dst, char *bc, size_t len) {
     Module *Dst = unwrap(dst);
 #if LLVM_VERSION_MINOR >= 6
     std::unique_ptr<MemoryBuffer> buf = MemoryBuffer::getMemBufferCopy(StringRef(bc, len));
+#if LLVM_VERSION_MINOR >= 7
+    ErrorOr<std::unique_ptr<Module>> Src =
+        llvm::getLazyBitcodeModule(std::move(buf), Dst->getContext());
+#else
     ErrorOr<Module *> Src = llvm::getLazyBitcodeModule(std::move(buf), Dst->getContext());
+#endif
 #else
     MemoryBuffer* buf = MemoryBuffer::getMemBufferCopy(StringRef(bc, len));
     ErrorOr<Module *> Src = llvm::getLazyBitcodeModule(buf, Dst->getContext());
@@ -739,7 +811,11 @@ LLVMRustLinkInExternalBitcode(LLVMModuleRef dst, char *bc, size_t len) {
 #if LLVM_VERSION_MINOR >= 6
     raw_string_ostream Stream(Err);
     DiagnosticPrinterRawOStream DP(Stream);
+#if LLVM_VERSION_MINOR >= 7
+    if (Linker::LinkModules(Dst, Src->get(), [&](const DiagnosticInfo &DI) { DI.print(DP); })) {
+#else
     if (Linker::LinkModules(Dst, *Src, [&](const DiagnosticInfo &DI) { DI.print(DP); })) {
+#endif
 #else
     if (Linker::LinkModules(Dst, *Src, Linker::DestroySource, &Err)) {
 #endif
@@ -813,8 +889,12 @@ extern "C" const Archive::Child*
 LLVMRustArchiveIteratorCurrent(RustArchiveIterator *rai) {
     if (rai->cur == rai->end)
         return NULL;
+#if LLVM_VERSION_MINOR >= 6
     const Archive::Child &ret = *rai->cur;
     return &ret;
+#else
+    return rai->cur.operator->();
+#endif
 }
 
 extern "C" void
@@ -942,7 +1022,11 @@ extern "C" void LLVMWriteDebugLocToString(
     RustStringRef str)
 {
     raw_rust_string_ostream os(str);
+#if LLVM_VERSION_MINOR >= 7
+    unwrap(dl)->print(os);
+#else
     unwrap(dl)->print(*unwrap(C), os);
+#endif
 }
 
 DEFINE_SIMPLE_CONVERSION_FUNCTIONS(SMDiagnostic, LLVMSMDiagnosticRef)