commit 456ca048af35163b9f52187e92a23ee0a9f059e8
author Stephen Lin <stephenwlin@gmail.com> Sat Apr 20 05:14:40 2013 +0000
committer Stephen Lin <stephenwlin@gmail.com> Sat Apr 20 05:14:40 2013 +0000
tree f7b4d4711424b927d5b323a9e4ef4d97742beeb4
parent 5c34e08b9fff9d4df2421e4f41ff15b85f638dd1

Add CodeGen support for functions that always return arguments via a new parameter attribute 'returned', which is taken advantage of in target-independent tail call opportunity detection and in ARM call lowering (when placed on an integral first parameter).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179925 91177308-0d34-0410-b5e6-96231b3b80d8

lib/AsmParser/LLLexer.cpp

diff --git a/lib/AsmParser/LLLexer.cpp b/lib/AsmParser/LLLexer.cpp
index f46383b..e7a9f2a 100644
--- a/lib/AsmParser/LLLexer.cpp
+++ b/lib/AsmParser/LLLexer.cpp
@@ -582,6 +582,7 @@
   KEYWORD(optsize);
   KEYWORD(readnone);
   KEYWORD(readonly);
+  KEYWORD(returned);
   KEYWORD(returns_twice);
   KEYWORD(signext);
   KEYWORD(sret);

lib/AsmParser/LLParser.cpp

diff --git a/lib/AsmParser/LLParser.cpp b/lib/AsmParser/LLParser.cpp
index 8fa626d..92756ba 100644
--- a/lib/AsmParser/LLParser.cpp
+++ b/lib/AsmParser/LLParser.cpp
@@ -944,6 +944,7 @@
     case lltok::kw_nest:
     case lltok::kw_noalias:
     case lltok::kw_nocapture:
+    case lltok::kw_returned:
     case lltok::kw_sret:
       HaveError |=
         Error(Lex.getLoc(),
@@ -1156,6 +1157,7 @@
     case lltok::kw_nest:            B.addAttribute(Attribute::Nest); break;
     case lltok::kw_noalias:         B.addAttribute(Attribute::NoAlias); break;
     case lltok::kw_nocapture:       B.addAttribute(Attribute::NoCapture); break;
+    case lltok::kw_returned:        B.addAttribute(Attribute::Returned); break;
     case lltok::kw_signext:         B.addAttribute(Attribute::SExt); break;
     case lltok::kw_sret:            B.addAttribute(Attribute::StructRet); break;
     case lltok::kw_zeroext:         B.addAttribute(Attribute::ZExt); break;
@@ -1199,6 +1201,7 @@
     case lltok::kw_byval:
     case lltok::kw_nest:
     case lltok::kw_nocapture:
+    case lltok::kw_returned:
     case lltok::kw_sret:
       HaveError |= Error(Lex.getLoc(), "invalid use of parameter-only attribute");
       break;

lib/AsmParser/LLToken.h

diff --git a/lib/AsmParser/LLToken.h b/lib/AsmParser/LLToken.h
index cd25ba3..3bf54fa 100644
--- a/lib/AsmParser/LLToken.h
+++ b/lib/AsmParser/LLToken.h
@@ -114,6 +114,7 @@
     kw_optsize,
     kw_readnone,
     kw_readonly,
+    kw_returned,
     kw_returns_twice,
     kw_signext,
     kw_ssp,