From a534a381304efc038276f426a756f5c56834bbc5 Mon Sep 17 00:00:00 2001 From: Reid Kleckner Date: Thu, 19 Dec 2013 02:14:12 +0000 Subject: Begin adding docs and IR-level support for the inalloca attribute The inalloca attribute is designed to support passing C++ objects by value in the Microsoft C++ ABI. It behaves the same as byval, except that it always implies that the argument is in memory and that the bytes are never copied. This attribute allows the caller to take the address of an outgoing argument's memory and execute arbitrary code to store into it. This patch adds basic IR support, docs, and verification. It does not attempt to implement any lowering or fix any possibly broken transforms. When this patch lands, a complete description of this feature should appear at http://llvm.org/docs/InAlloca.html . Differential Revision: http://llvm-reviews.chandlerc.com/D2173 llvm-svn: 197645 --- llvm/lib/IR/Function.cpp | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'llvm/lib/IR/Function.cpp') diff --git a/llvm/lib/IR/Function.cpp b/llvm/lib/IR/Function.cpp index e8a2402b3d9..970bbaeed8b 100644 --- a/llvm/lib/IR/Function.cpp +++ b/llvm/lib/IR/Function.cpp @@ -84,6 +84,14 @@ bool Argument::hasByValAttr() const { hasAttribute(getArgNo()+1, Attribute::ByVal); } +/// \brief Return true if this argument has the inalloca attribute on it in +/// its containing function. +bool Argument::hasInAllocaAttr() const { + if (!getType()->isPointerTy()) return false; + return getParent()->getAttributes(). + hasAttribute(getArgNo()+1, Attribute::InAlloca); +} + unsigned Argument::getParamAlignment() const { assert(getType()->isPointerTy() && "Only pointers have alignments"); return getParent()->getParamAlignment(getArgNo()+1); -- cgit v1.2.3