From 98a49337be3fdf2c4bfa6cccc50fbb5d2aa7e3be Mon Sep 17 00:00:00 2001 From: Akira Hatanaka Date: Fri, 22 Sep 2017 00:41:05 +0000 Subject: Add support for attribute 'noescape'. The attribute informs the compiler that the annotated pointer parameter of a function cannot escape and enables IRGen to attach attribute 'nocapture' to parameters that are annotated with the attribute. That is the only optimization that currently takes advantage of 'noescape', but there are other optimizations that will be added later that improves IRGen for ObjC blocks. This recommits r313722, which was reverted in r313725 because clang couldn't build compiler-rt. It failed to build because there were function declarations that were missing 'noescape'. That has been fixed in r313929. rdar://problem/19886775 Differential Revision: https://reviews.llvm.org/D32210 llvm-svn: 313945 --- clang/lib/CodeGen/CGCall.cpp | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'clang/lib/CodeGen/CGCall.cpp') diff --git a/clang/lib/CodeGen/CGCall.cpp b/clang/lib/CodeGen/CGCall.cpp index c6988b5a9f3..a432c3ca20d 100644 --- a/clang/lib/CodeGen/CGCall.cpp +++ b/clang/lib/CodeGen/CGCall.cpp @@ -455,11 +455,15 @@ const CGFunctionInfo & CodeGenTypes::arrangeObjCMessageSendSignature(const ObjCMethodDecl *MD, QualType receiverType) { SmallVector argTys; + SmallVector extParamInfos(2); argTys.push_back(Context.getCanonicalParamType(receiverType)); argTys.push_back(Context.getCanonicalParamType(Context.getObjCSelType())); // FIXME: Kill copy? for (const auto *I : MD->parameters()) { argTys.push_back(Context.getCanonicalParamType(I->getType())); + auto extParamInfo = FunctionProtoType::ExtParameterInfo().withIsNoEscape( + I->hasAttr()); + extParamInfos.push_back(extParamInfo); } FunctionType::ExtInfo einfo; @@ -475,7 +479,7 @@ CodeGenTypes::arrangeObjCMessageSendSignature(const ObjCMethodDecl *MD, return arrangeLLVMFunctionInfo( GetReturnType(MD->getReturnType()), /*instanceMethod=*/false, - /*chainCall=*/false, argTys, einfo, {}, required); + /*chainCall=*/false, argTys, einfo, extParamInfos, required); } const CGFunctionInfo & @@ -2093,6 +2097,9 @@ void CodeGenModule::ConstructAttributeList( break; } + if (FI.getExtParameterInfo(ArgNo).isNoEscape()) + Attrs.addAttribute(llvm::Attribute::NoCapture); + if (Attrs.hasAttributes()) { unsigned FirstIRArg, NumIRArgs; std::tie(FirstIRArg, NumIRArgs) = IRFunctionArgs.getIRArgs(ArgNo); -- cgit v1.2.3