Revert "[AArch64] FMV support and necessary target features dependencies."

This reverts commit e43924a75145d2f9e722f74b673145c3e62bfd07.

Reason: Patch broke the MSan buildbots. More information is available on
the original phabricator review: https://reviews.llvm.org/D127812

1 files changed, 5 insertions, 83 deletions

diff --git a/clang/lib/CodeGen/CodeGenFunction.cpp b/clang/lib/CodeGen/CodeGenFunction.cpp
index 4125730..874a083 100644
--- a/clang/lib/CodeGen/CodeGenFunction.cpp
+++ b/clang/lib/CodeGen/CodeGenFunction.cpp
@@ -2627,22 +2627,8 @@ void CodeGenFunction::EmitKCFIOperandBundle(
     Bundles.emplace_back("kcfi", CGM.CreateKCFITypeId(FP->desugar()));
 }
 
-llvm::Value *CodeGenFunction::FormAArch64ResolverCondition(
-    const MultiVersionResolverOption &RO) {
-  llvm::SmallVector<StringRef, 8> CondFeatures;
-  for (const StringRef &Feature : RO.Conditions.Features) {
-    // Form condition for features which are not yet enabled in target
-    if (!getContext().getTargetInfo().hasFeature(Feature))
-      CondFeatures.push_back(Feature);
-  }
-  if (!CondFeatures.empty()) {
-    return EmitAArch64CpuSupports(CondFeatures);
-  }
-  return nullptr;
-}
-
-llvm::Value *CodeGenFunction::FormX86ResolverCondition(
-    const MultiVersionResolverOption &RO) {
+llvm::Value *
+CodeGenFunction::FormResolverCondition(const MultiVersionResolverOption &RO) {
   llvm::Value *Condition = nullptr;
 
   if (!RO.Conditions.Architecture.empty())
@@ -2680,72 +2666,8 @@ static void CreateMultiVersionResolverReturn(CodeGenModule &CGM,
 
 void CodeGenFunction::EmitMultiVersionResolver(
     llvm::Function *Resolver, ArrayRef<MultiVersionResolverOption> Options) {
-
-  llvm::Triple::ArchType ArchType =
-      getContext().getTargetInfo().getTriple().getArch();
-
-  switch (ArchType) {
-  case llvm::Triple::x86:
-  case llvm::Triple::x86_64:
-    EmitX86MultiVersionResolver(Resolver, Options);
-    return;
-  case llvm::Triple::aarch64:
-    EmitAArch64MultiVersionResolver(Resolver, Options);
-    return;
-
-  default:
-    assert(false && "Only implemented for x86 and AArch64 targets");
-  }
-}
-
-void CodeGenFunction::EmitAArch64MultiVersionResolver(
-    llvm::Function *Resolver, ArrayRef<MultiVersionResolverOption> Options) {
-  assert(!Options.empty() && "No multiversion resolver options found");
-  assert(Options.back().Conditions.Features.size() == 0 &&
-         "Default case must be last");
-  bool SupportsIFunc = getContext().getTargetInfo().supportsIFunc();
-  assert(SupportsIFunc &&
-         "Multiversion resolver requires target IFUNC support");
-  bool AArch64CpuInitialized = false;
-  llvm::BasicBlock *CurBlock = createBasicBlock("resolver_entry", Resolver);
-
-  for (const MultiVersionResolverOption &RO : Options) {
-    Builder.SetInsertPoint(CurBlock);
-    llvm::Value *Condition = FormAArch64ResolverCondition(RO);
-
-    // The 'default' or 'all features enabled' case.
-    if (!Condition) {
-      CreateMultiVersionResolverReturn(CGM, Resolver, Builder, RO.Function,
-                                       SupportsIFunc);
-      return;
-    }
-
-    if (!AArch64CpuInitialized) {
-      Builder.SetInsertPoint(CurBlock, CurBlock->begin());
-      EmitAArch64CpuInit();
-      AArch64CpuInitialized = true;
-      Builder.SetInsertPoint(CurBlock);
-    }
-
-    llvm::BasicBlock *RetBlock = createBasicBlock("resolver_return", Resolver);
-    CGBuilderTy RetBuilder(*this, RetBlock);
-    CreateMultiVersionResolverReturn(CGM, Resolver, RetBuilder, RO.Function,
-                                     SupportsIFunc);
-    CurBlock = createBasicBlock("resolver_else", Resolver);
-    Builder.CreateCondBr(Condition, RetBlock, CurBlock);
-  }
-
-  // If no default, emit an unreachable.
-  Builder.SetInsertPoint(CurBlock);
-  llvm::CallInst *TrapCall = EmitTrapCall(llvm::Intrinsic::trap);
-  TrapCall->setDoesNotReturn();
-  TrapCall->setDoesNotThrow();
-  Builder.CreateUnreachable();
-  Builder.ClearInsertionPoint();
-}
-
-void CodeGenFunction::EmitX86MultiVersionResolver(
-    llvm::Function *Resolver, ArrayRef<MultiVersionResolverOption> Options) {
+  assert(getContext().getTargetInfo().getTriple().isX86() &&
+         "Only implemented for x86 targets");
 
   bool SupportsIFunc = getContext().getTargetInfo().supportsIFunc();
 
@@ -2756,7 +2678,7 @@ void CodeGenFunction::EmitX86MultiVersionResolver(
 
   for (const MultiVersionResolverOption &RO : Options) {
     Builder.SetInsertPoint(CurBlock);
-    llvm::Value *Condition = FormX86ResolverCondition(RO);
+    llvm::Value *Condition = FormResolverCondition(RO);
 
     // The 'default' or 'generic' case.
     if (!Condition) {