Bump minimum required LLVM version to 6.0

src/rustllvm/ArchiveWrapper.cpp

@@ -216,16 +216,11 @@ LLVMRustWriteArchive(char *Dst, size_t NumMembers,
       Members.push_back(std::move(*MOrErr));
     }
   }
+
   auto Result = writeArchive(Dst, Members, WriteSymbtab, Kind, true, false);
-#if LLVM_VERSION_GE(6, 0)
   if (!Result)
     return LLVMRustResult::Success;
   LLVMRustSetLastError(toString(std::move(Result)).c_str());
-#else
-  if (!Result.second)
-    return LLVMRustResult::Success;
-  LLVMRustSetLastError(Result.second.message().c_str());
-#endif
 
   return LLVMRustResult::Failure;
 }

src/rustllvm/PassWrapper.cpp

@@ -17,21 +17,15 @@
 
 #include "llvm/Analysis/TargetLibraryInfo.h"
 #include "llvm/Analysis/TargetTransformInfo.h"
+#include "llvm/CodeGen/TargetSubtargetInfo.h"
 #include "llvm/IR/AutoUpgrade.h"
 #include "llvm/IR/AssemblyAnnotationWriter.h"
+#include "llvm/IR/IntrinsicInst.h"
 #include "llvm/Support/CBindingWrapping.h"
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/Host.h"
 #include "llvm/Target/TargetMachine.h"
 #include "llvm/Transforms/IPO/PassManagerBuilder.h"
-
-#if LLVM_VERSION_GE(6, 0)
-#include "llvm/CodeGen/TargetSubtargetInfo.h"
-#include "llvm/IR/IntrinsicInst.h"
-#else
-#include "llvm/Target/TargetSubtargetInfo.h"
-#endif
-
 #include "llvm/Transforms/IPO/AlwaysInliner.h"
 #include "llvm/Transforms/IPO/FunctionImport.h"
 #include "llvm/Transforms/Utils/FunctionImportUtils.h"
@@ -198,13 +192,9 @@ GEN_SUBTARGETS
 
 extern "C" bool LLVMRustHasFeature(LLVMTargetMachineRef TM,
                                    const char *Feature) {
-#if LLVM_VERSION_GE(6, 0)
   TargetMachine *Target = unwrap(TM);
   const MCSubtargetInfo *MCInfo = Target->getMCSubtargetInfo();
   return MCInfo->checkFeatures(std::string("+") + Feature);
-#else
-  return false;
-#endif
 }
 
 enum class LLVMRustCodeModel {
@@ -392,13 +382,9 @@ extern "C" LLVMTargetMachineRef LLVMRustCreateTargetMachine(
     Options.ThreadModel = ThreadModel::Single;
   }
 
-#if LLVM_VERSION_GE(6, 0)
   Options.EmitStackSizeSection = EmitStackSizeSection;
 
   Optional<CodeModel::Model> CM;
-#else
-  CodeModel::Model CM = CodeModel::Model::Default;
-#endif
   if (RustCM != LLVMRustCodeModel::None)
     CM = fromRust(RustCM);
   TargetMachine *TM = TheTarget->createTargetMachine(

src/rustllvm/RustWrapper.cpp

@@ -297,11 +297,7 @@ extern "C" void LLVMRustRemoveFunctionAttributes(LLVMValueRef Fn,
 // enable fpmath flag UnsafeAlgebra
 extern "C" void LLVMRustSetHasUnsafeAlgebra(LLVMValueRef V) {
   if (auto I = dyn_cast<Instruction>(unwrap<Value>(V))) {
-#if LLVM_VERSION_GE(6, 0)
     I->setFast(true);
-#else
-    I->setHasUnsafeAlgebra(true);
-#endif
   }
 }
 
@@ -1437,7 +1433,6 @@ LLVMRustBuildVectorReduceFMax(LLVMBuilderRef B, LLVMValueRef Src, bool NoNaN) {
   return wrap(unwrap(B)->CreateFPMaxReduce(unwrap(Src), NoNaN));
 }
 
-#if LLVM_VERSION_GE(6, 0)
 extern "C" LLVMValueRef
 LLVMRustBuildMinNum(LLVMBuilderRef B, LLVMValueRef LHS, LLVMValueRef RHS) {
     return wrap(unwrap(B)->CreateMinNum(unwrap(LHS),unwrap(RHS)));
@@ -1446,13 +1441,3 @@ extern "C" LLVMValueRef
 LLVMRustBuildMaxNum(LLVMBuilderRef B, LLVMValueRef LHS, LLVMValueRef RHS) {
     return wrap(unwrap(B)->CreateMaxNum(unwrap(LHS),unwrap(RHS)));
 }
-#else
-extern "C" LLVMValueRef
-LLVMRustBuildMinNum(LLVMBuilderRef, LLVMValueRef, LLVMValueRef) {
-   return nullptr;
-}
-extern "C" LLVMValueRef
-LLVMRustBuildMaxNum(LLVMBuilderRef, LLVMValueRef, LLVMValueRef) {
-   return nullptr;
-}
-#endif