Apply 0032-shrinkwrap-control.patch

Author: dpaoliello

clang/include/clang/Basic/Attr.td

@@ -5262,3 +5262,10 @@ def DynamicFixup : InheritableAttr {
   let LangOpts = [MicrosoftExt];
   let Documentation = [Undocumented];
 }
+
+def NoShrinkWrapping : InheritableAttr {
+  let Spellings = [Declspec<"noshrinkwrap">];
+  let Subjects = SubjectList<[Function]>;
+  let Documentation = [NoShrinkWrappingDocs];
+  let SimpleHandler = 1;
+}

clang/include/clang/Basic/AttrDocs.td

@@ -9427,3 +9427,12 @@ silence diagnostics with code like:
   __attribute__((nonstring)) char NotAStr[3] = "foo"; // Not diagnosed
   }];
 }
+
+def NoShrinkWrappingDocs : Documentation {
+  let Category = DocCatFunction;
+  let Content = [{
+  The ``__declspec(noshrinkwrap)`` attribute disables the shrinkwrapping
+  process for this function.
+  }];
+}
+

clang/lib/CodeGen/CodeGenModule.cpp

@@ -2641,6 +2641,10 @@ void CodeGenModule::SetLLVMFunctionAttributesForDefinition(const Decl *D,
   else if (isStackProtectorOn(LangOpts, getTriple(), LangOptions::SSPReq))
     B.addAttribute(llvm::Attribute::StackProtectReq);
 
+  if (D && D->hasAttr<NoShrinkWrappingAttr>()) {
+    B.addAttribute(llvm::Attribute::NoShrinkWrap);
+  }
+
   if (!D) {
     // Non-entry HLSL functions must always be inlined.
     if (getLangOpts().HLSL && !F->hasFnAttribute(llvm::Attribute::NoInline))

clang/lib/Sema/SemaDeclAttr.cpp

@@ -7895,6 +7895,10 @@ ProcessDeclAttribute(Sema &S, Scope *scope, Decl *D, const ParsedAttr &AL,
     handleDynamicFixup(S, D, AL);
     break;
 
+  case ParsedAttr::AT_NoShrinkWrapping:
+    handleSimpleAttribute<NoShrinkWrappingAttr>(S, D, AL);
+    break;
+
   }
 }
 

llvm/include/llvm/Bitcode/LLVMBitCodes.h

@@ -695,6 +695,9 @@ enum UseListCodes {
 };
 
 enum AttributeKindCodes {
+  // TODO: assign real values; these are placed here to reduce likelihood of merge conflicts with additions
+  ATTR_KIND_NO_SHRINKWRAP = INT_MAX,
+
   // = 0 is unused
   ATTR_KIND_ALIGNMENT = 1,
   ATTR_KIND_ALWAYS_INLINE = 2,

llvm/include/llvm/IR/Attributes.td

@@ -402,6 +402,9 @@ def MarkedForWindowsSecureHotPatching
 def AllowDirectAccessInHotPatchFunction
     : StrBoolAttr<"allow_direct_access_in_hot_patch_function">;
 
+/// Function should not be shrinkwrapped
+def NoShrinkWrap : EnumAttr<"noshrinkwrap", IntersectPreserve, [FnAttr]>;
+
 /// Target-independent string attributes.
 def LessPreciseFPMAD : StrBoolAttr<"less-precise-fpmad">;
 def NoInfsFPMath : StrBoolAttr<"no-infs-fp-math">;

llvm/lib/Bitcode/Reader/BitcodeReader.cpp

@@ -2246,6 +2246,8 @@ static Attribute::AttrKind getAttrFromCode(uint64_t Code) {
     return Attribute::Captures;
   case bitc::ATTR_KIND_DEAD_ON_RETURN:
     return Attribute::DeadOnReturn;
+  case bitc::ATTR_KIND_NO_SHRINKWRAP:
+    return Attribute::NoShrinkWrap;
   }
 }
 

llvm/lib/Bitcode/Writer/BitcodeWriter.cpp

@@ -946,6 +946,8 @@ static uint64_t getAttrKindEncoding(Attribute::AttrKind Kind) {
     return bitc::ATTR_KIND_CAPTURES;
   case Attribute::DeadOnReturn:
     return bitc::ATTR_KIND_DEAD_ON_RETURN;
+  case Attribute::NoShrinkWrap:
+    return bitc::ATTR_KIND_NO_SHRINKWRAP;
   case Attribute::EndAttrKinds:
     llvm_unreachable("Can not encode end-attribute kinds marker.");
   case Attribute::None:

llvm/lib/CodeGen/ShrinkWrap.cpp

@@ -1013,6 +1013,9 @@ PreservedAnalyses ShrinkWrapPass::run(MachineFunction &MF,
 bool ShrinkWrapImpl::isShrinkWrapEnabled(const MachineFunction &MF) {
   const TargetFrameLowering *TFI = MF.getSubtarget().getFrameLowering();
 
+  if (MF.getFunction().hasFnAttribute(Attribute::NoShrinkWrap))
+      return false;
+
   switch (EnableShrinkWrapOpt) {
   case cl::BOU_UNSET:
     return TFI->enableShrinkWrapping(MF) &&